key: cord-0034116-arfmw07f
authors: nan
title: C scientific exhibits (SE)
date: 2002
journal: Eur Radiol
DOI: 10.1007/s00330-002-0003-8
sha: 4f6dd305b7a52c16d75728199306889d28b3588d
doc_id: 34116
cord_uid: arfmw07f

nan

To provide an imaging overview of common and uncommon complications seen with liver transplantation in adults and discuss the respective roles of Doppler ultrasonography, helical CT and MRI for detection and follow-up. Methods and materials: We reviewed the files of 1000 consecutive hepatic transplant recipients and assessed the diagnostic potential of Doppler ultrasonography, helical CT and MRI for the diagnosis, pre-therapeutic staging and follow-up of complications. The results were compared to those obtained by more invasive imaging modalities including arteriography and cholangiography as well as to operative findings and follow up. Results: Biliary complications were observed in 20 % patients, infectious abdominal complications in 4 %, and vascular complications in 4 %. Less than 0.01 % of the complications involved the hepatic veins and 1 % of the complications consisted in portal thrombosis and stenosis. For each group of complications the imaging strategy is discussed. Conclusion: Doppler ultrasonography is able to detect vascular, biliary, neoplastic, parenchymal and perihepatic complications. CT is essential for the evaluation of intraabdominal collections and neoplastic disease. MR angiography and MR cholangiography have an increasing role and should avoid uneccessary invasive imaging modalities.

Estimation of hepatic tumors vascularity and assessment of chemoembolization efficacy by dual-phase angiohepatoscintigraphy N.P. Fadeev, D.A. Granov, A.A. Ivanova, T.S. Dubrovina; St. Petersburg/RU Chemoembolization (CE) at present is the method of choice in patients with hepatic tumors (especially in cases of multiple metastases), while the success of CE mainly depends on the obtaining of the information about vascularity of lesion. Purpose: Of this study was to evaluate dual-phase angiohepatoscintigraphy (DP-AHSG) for estimation of vascularity and assessment of CE efficacy in patients with hepatic tumors. Material and methods: 27 patients (middle age 42 a) with hystologicaly verified malignancies of the liver (HCC n = 7, and metastases n = 20) were evaluated. DP-AHSG using 99 Tc-colloids was performed on APEX SP-6 γ-camera (Elscint) just after i.v. injection of tracer bolus in dynamic mode: early (angio) phase -first 60 seconds -and late (parenchymal) phase. Frames of each time interval were summarized and sum of the second phase were subtracted from the first one. The uptake of radiopharmaceutical at the resulting scintigrams noted the vascularity of hepatic lesions (Patent Nº 2156112). Results: In 22 of 27 patients the hypervascular foci were visualized: in 5 pts with HCC and in 17 with hepatic metastases. DP-AHSG data were compared with the angiography results in the same patients: in 88 % there were concordance of the results, in 12 % DP-AHSG data were false-negative. 7 patients assessed by DP-AHSG before and after CE showed successful embolization and in one patient CE was ineffective. Conclusion: DP-AHSG is non-invasive and safe method with low radiation dose that is feasible for repeated studies and can be used in vascularity estimation and assessment of CE efficacy.

The general part of this CD-ROM is displayed in chapters that deal with liver anatomy, liver hemodynamics, CLD and portal hypertension as well as benign and malignant focal liver lesions. Interesting cases are illustrated by videos that provide a step-by-step presentation of the liver U/S examination and homodynamic study, so that conclusions about ultrasound possibilities and limitations can be drawn by the user himself. The aim of this project, to teach the U/S technique, is reached mainly by the double video presentations. Namely, there is a simultaneous presentation of: (a) the examiner and his manipulations with the transducer and (b) the real-time ultrasound examination. The organised display of this CD-ROM with an index module, mouse pointers, links and speech explanations makes it an easy-to-use, self-training tool for the training radiologist. U/S of CLD and focal lesions is reviewed by means of context, commented images, image galleries and video cases.

Complications of liver transplantation used by dual left lobes H. Kim; Seoul/KR Purpose: To demonstrate the complications of liver transplantation used by dual left lobes obtained from two donors with an insufficient small left lobe to maintain a donor's life. Methods and materials: From March 2000 to April 2001, dual left lobes transplantation in adult-to-adult was performed in thirteen patients. We reviewed radiologic studies including ultrasound, CT and angiography obtained post-transplantation and analyzed vascular, biliary, other complications, and rejection Results: Vascular complications were noted in heparic artery stenosis in two patients, hepatic artery obstruction in one, hepatic artery dissection in one, heparic artery pseudoaneurysm in one. Portal vein stenosis was noted in two patients. Hepatic vein stenosis were noted in five patients. Jejunal bleeding and intercostal arterial bleeding were noted each one. Biliary complication and rejection were only noted in one patient each one. Conclusion: Complications after left dual lobes liver transplantation are similar to other living donor liver transplantation and vascular complications are predominant.

Usefullness of low tube operating potential (TOP) for improved detection of minimally contrast-enhanced nodules on CT T. Ishida, K. Higashimura, H. Itou; Fukui/JP Purpose: We recently observed that hepatic nodules which were only minimally enhanced on dynamic CT were much better visualized using a low TOP in spite of some increase of the background noise. The purpose of this study is to evaluate the potential superiority of low TOP in detecting minimally contrast-enhanced hepatic nodules on CT. Methods and materials: A phantom was made of anger and contrast medium. Four anger columns were made four different concentrations of contrast media (0.8 %, 1.0 % 1.5 % 1.8 %). The phantom was scanned using different TOP (80, 100, 120, 140 kVp) . Detectability of the columns were also evaluated contrast to noise ratio (CNR) and visually by radiologists in a doubleblind fashion. Weighted computed tomography dose index (CTDIw) was compared with different TOP. In the clinical study, seven patients were studied. The diagnostic usefulness of a TOP of 80 kVp was compared with that of 120 kVp in same patient by Dynamic CT which has better detectability of minimally contrast enhancing nodules. Result: With using lower TOP, CNR was increased. On visual evaluation by radiologists, images taken at 80 kVp achieved the highest detectability of the columns. CTDIw associated with the 80, 100, 120, 140 kVp at one scan were 5.78 mGy, 6.64 mGy, 8.13 mGy, 11.02 mGy, respectivry. In the clinical study a lesion could be detected clearly with a low TOP of 80 kVp though the existence of the lesion could not be detected at 120 kVp. The existence of the HCC was proven with DSA, CTA and CTAP. Conclusion: CT operated at a TOP of 80 kVp has potentially better detectability of minimally contrast-enhanced nodules than 120 kVp.

Multiphase contrast-enhanced CT of the liver with a multislice CT scanner: Effects of rate of contrast material injection and a 5% dextrose flush on enhancement in the liver S. Itoh, M. Ikeda, M. Achiwa, H. Satake, T. Ota, T. Ishigaki; Nagoya/JP Purpose: To assess the effects of the injection rate of contrast material and a 5% dextrose flush on enhancement in multiphase hepatic CT with a multislice CT scanner.

One hundred and 80 examinations in which two sequential acquisitions were performed during a single breath-hold followed by third-and fourth-pass acquisitions were randomized into four protocols: 0.1 ml/kg body weight/ s over 21 s without and with a 30 ml flush in Groups 1 and 2, respectively, and 0.07 ml/kg body weight/s over 30 s without and with a flush in Groups 3 and 4, respectively. Contrast enhancement in each acquisition was measured in the aorta, portal vein, and liver. Visualization of the hepatic arterial branches was scored visually.

Results: Aortic peak enhancement occurred during the first-pass acquisition in all groups. With a higher injection rate, aortic enhancement in the first pass was significantly more intense, while portal venous enhancement and hepatic enhancement were significantly less intense. The use of a flush markedly improved aortic enhancement at the beginning of the second-pass aquisition. With a higher injection rate, visual assessment of the hepatic arterial branches showed significantly higher scores. Conclusion: Multislice CT can be used to image the entire liver during an almost exclusively arterial phase by shortening the duration of injection for a given volume of contrast material.

Hypervascular metastases to the liver from colon cancer: CT, MR findings G. Tognini 1 , F. Ferrozzi 1, 2 , P. Bini 1 , A. Patti 1 , E. Spaggiari 1 , P. Pavone 1 ; 1 Parma/IT, 2 Cremona/IT Purpose: Metastases to the liver, and in particular those from colon cancers, are generally hypovascular. Rarely metastases to the liver from colon cancers may show frankly hypervascular appearance so that they must be differentiated from benign angiomatous lesions of the organ. The aim of our scientific exhibit is to describe the CT and MR features of such atypical lesions. Materials and methods: We retrospectively reviewed CT, MR findings of 128 patients with pathologically proved liver metastases from colon cancers among whom 7 (4 FF, 3 MM) showed atypical frankly hypervascular patterns. CT protocol included 5 mm collimation, pitch: 1.5, injection of iodinated contrast medium (rate: 3 -3.5 ml/s); MR protocol included 5 -8 mm slice thickness, T1, T2 weighted sequences and post-Gd evaluation. Results: The lesions ranged in size from 3 to 7 cm; 2 were single 5 multiple. Plain CT showed hypodensity of the lesions without calcifications. Enhanced CT showed the frankly hypervascular appearance of the lesions with global delayed hemangioma-like enhancement. MR findings closely paralleled CT features; MR better demonstrated structural heterogeneities: T2 weighted-images demonstrated hypointense components (stromal); enhanced MR better depicted the stronger central hypervascularity. Conclusions: Enhanced MR thanks to its unique capabilities of structural evaluation plays an elective role in the characterization.

Purpose: To evaluate the characteristic MR findings and histopathologic correlation of peritumoral fat sparing of liver metastases in patients with underlying fatty liver. Methods and materials: Six patients (M:F = 3:3, age range: 32 -75, mean age: 51) with peritumoral fat sparing of liver metastases on MR images were evaluated to compare MR findings with histopathology. Primary cancers of six patients were composed of colon cancer (n = 4), ileal carcinoid (n = 1) and breast cancer (n = 1). Precontrast in-phase (TR/TE 140/4.5) and out-of-phase (TR/TE 140/2.2) axial spoiled gradient echo (SGE) images, T2-weighted axial inversion recovery (TR/ TE, 5110/76) MR image, and postcontrast T1-weighted axial image were obtained. Results: All 6 patients showed the peritumoral high signal intensity lesions surrounding the metastatic tumors well contrasted by a diffusely decreased signal intensity of remaining liver parenchyma, which were composed of 3 cases of polygonal shape and 3 cases of wedge shape. Rim of peritumoral fat sparing (decreased steatosis) was histopathologically confirmed between the tumor mass and normal fatty liver in all cases. The cause of fat sparing in our case might be from the microinvasion of portal venules by the hematogenous metastatic tumor emboli or external compression of portal vein by the tumor mass itself, causing decreased perfusion of portal flow. Conclusion: Out-of-phase T1-weighted MR image is useful in characterizing the peritumoral fat sparing of liver metastases in patients with underlying fatty liver, which may be isointense with adjacent liver parenchyma in in-phase T1-weighted, precontrast T2-weighted and postcontrast T1-weighted MR images.

Single-injection hepatic radionuclide angiography and hepatobiliary scintigraphy in the evaluation of liver transplant function V.B. Obradovic, V.M. Artiko, B. Radevic, R. Jesic, B. Dapcevic, N. Petrovic; Belgrade/YU Purpose: The aim is evaluation of the perfusion, morphology and the biliary three patientcy of the liver transplants by two radionuclide methods. Patients and methods: The study was performed in 10 controls and 10 patients after orthotopic transplantation (up to two years). "First pass" dynamic acquisition was performed with scintillation camera, after bolus injection of 360 MBq 99 Tc-diethyl-IDA, (60 frames/60 s), continued by 59 minutes (1 frame/min) slower dynamic study. From the liver and kidney activity during "first pass" study, hepatic perfusion index (HPI) was calculated using slope-analysis. Hepatobiliary scintigrams obtained during second phase of the study were analysed for morphology, and parenchymal and hepatobiliary TA curves were generated and analysed according to the time to maximal acitivity (Tmax) and the time to half of maximum acitivity (T/2).

CT study of the distribution of boron-lipiodol in VX2 hepatoma rabbit model Y. Lin 1 , I. Wu 1 , Y. Ho 1 , S. Chen 1 , F. Chou 2 , J. Kai 2 , W. Lui 3 , C. Chi 3 ; 1 Taichung/TW, 2 Hsinchu/TW, 3 Taipei/TW Purpose: To evaluate the potential of using boron-lipiodol agent for the detection and treatment of VX2 hepatoma in rabbit. Materials and methods: Twelve New Zealand rabbits were randomly separated into lipiodol and boron-lipiodol groups. Rabbits were anesthetized, a midline incision was made and the left lobe of liver was injected with 0.1 ml of VX2 tumor cells. After the tumor reached 2 -3 cm in diameter, rabbits were anesthesized and 0.5 ml of boron-lipiodol injected into hepatic artery via angiocatheter. The distribution of boron lipiodol was recorded by angiography and boron level in tissue was determined by ICP-AES. Partial liver and tumor were embedded and examined histologically. Results: Rabbits with VX2-carcinoma show that no significant difference was observed in the retention of lipiodol and boron-lipiodol agent. The flow of boron-lipiodol in hepatic artery was slightly slower than the lipiodol, both normal liver and tumor showed retention of boron-lipiodol at 10 minutes after injection. Majority of the boron-lipiodol was excreted out of the normal liver and kidney at 48 hours after injection. Differential retention of boron-lipiodol was observed at 7 days after injection, with tumor showed significant retention and no retention in other tissues. The boron level in tumor was 49.7 ppm as compared to 1.1 ppm of the lipiodol group. No pathological change was observed in test. Conclusion: Boron-lipiodol showed similar imaging characteristics as that of lipiodol. No specific pathological changes were found in animals receiving boronlipiodol. Further study with the biodistribution and neutron irradiation effect is now in progress.

Combination therapy of radiotherapy and transarterial infusion chemotherapy with concurrent infusion of a vasoconstrictor for nonresectable advanced hepatic hilar duct cancer E. Komatsu, H. Kiyosue, S. Matsumoto, M. Wakisaka, K. Tomonari, Y. Hori, A. Matsumoto, H. Mori; Oita/JP Purpose: Hepatic hilar duct cancer has a poor prognosis and median survival rates of the patients with nonresectable cancer were reported as 6 -12 months. In this study, we investigated the efficacy of combined radiotherapy (RT) and transarterial chemotherapy with concurrent infusion of a vasoconstrictor in the treatment of advanced hepatic hilar duct cancer. Methods and materials: Between 1993 and 2000, 20 patients with hilar duct cancer pathologically confirmed were treated by the combined treatment. The median total dose of external beam RT was 41.4 Gy for 5 weeks. Transarterial chemotherapy was performed twice during RT, with infusion of epirubicin (20 mg), mitomycin C (10 mg)and 5-fluorouracil (500 mg) one minute after injection of epinrphrine via a catheter introduced in the hepatic arteries. Following the combined treatment, all patients underwent biliary endoprosthesis after evaluation of the initial response of the treatment by cholangiography. Initial responses based on cholangiography were classified into one of four degree as follows: CR, no stenosis; PR, relief of stenosis/obstruction; NC, no change; PD, progressive stenosis/obstruction. Complications associated with the treatment and survival rates were also analyzed. Result: Median follow-up was 10 months (range 3 -40). Initial responses were 1 CR (5 %), 9 PR (45 %) and 10 NC (50 %). Response rate was 50 %. Overall survival rates at 1, 2 and 3 years after treatment were 60.6 %, 40.6 %, and 20.3 %, respectively. No major complications were encountered. Conclusion: The combination therapy of radiotherapy and transarterial infusion chemotherapy with concurrent infusion of a vasoconstrictor is an effective and safe treatment for advanced hepatic hilar duct cancer and is able to improves the outcome.

Mangafodipir trisodium (Mn-DPDP)-enhanced MR imaging: Correlation of contrast enhancement of the hepatocellular carcinoma with histopathologic findings J. Lee, S.-H. Kim, S.K. Kim, W.J. Lee, H.K. Lim, S.J. Lee, C.K. Park; Seoul/KR Purpose: To correlate enhancement of the hepatocellular carcinoma (HCC) with histopathologic findings on mangafodipir trisodium (Mn-DPDP)-enhanced MR imaging. Materials and methods: 26 patients underwent Mn-DPDP-enhanced MR imaging. 39 HCCs was established by pathologic examination following surgical resection in all patients. Mn-DPDP-enhanced MR imaging consisted of pre and postcontrast in phase gradient-recalled-echo (GRE) T1-weighted image. 33 HCCs more than 10 mm in diameter were enrolled in the study. Qualitative analysis including enhancement degree of HCC and quantitative analysis including enhancement ratio and lesion to liver contrast-noise ratio (CNR) of HCC were done. Enhancement degree, enhancement ratio and lesion to liver CNR of HCCs were correlated with tumor size, histopathologic grade and presence of liver cirrhosis. Results: Enhancement degrees of 17 HCCs (< 3 cm) were high (n = 11), and iso (n = 6) signal intensity (SI) and enhancement degrees of 16 HCCs (> 3 cm) were low (n = 7), high (n = 6), and iso (n = 3) SI. HCC (< 3 cm) showed statistically higher lesion to liver CNR than HCC (> 3 cm) (p < 0.05). There were no statistical significances between enhancement ratio and lesion to liver CNR of HCC with histopathologic grade and presence of liver cirrhosis. Conclusion: On Mn-DPDP-enhanced MR imaging, HCC (< 3 cm) showed high or iso SI and higher lesion to liver CNR and HCC (> 3 cm) showed low or high SI and lower lesion to liver CNR. Histopathologic grade and presence of liver cirrhosis were not correlated with enhancement of HCC. confirmed pathologicaly. Each case was reviewed for the number of detectable lesion, signal intensity, type of enhancement in sCT and MR images and presence of scar. Results: The signal intensity in T1-and T2-weighted images was similar to surrounding parenchyma in 16/25 cases. Combined Tl-and T2-weighted images showed 5/25 lesions hypointense on T1 and isointense on T2. In 4 cases the lesion was hypointense in T1-and hyperintense in T2-weighted images. In 21 cases, the enhancement profile was followed: intensive homogeneous enhancement in arterial phase and rapidly decreased enhancement in portal and equilibrium phases. Four lesions presented homogeneous enhancement in arterial portal and equilibrium phase. The central scar was visible in 17 lesions in sCT and 19 in MRI. For FNH with diameter < 2 cm the central scar was undetectable. Conclusion: Dynamic MR and sCT images demonstrate characteristic features that may confident diagnosis of FNH.

Preoperative magnetic resonance imaging for living donor liver transplantation: Detection of bile duct and vascular anatomic variants or congenital abnormalities O. Helie, A. Aït Ameur, F. Minvielle, A. Dion, C. Leveque, Y. Cordoliani; Paris/FR Purpose: To detect by MRI abnormalities and anatomic variants of the biliary tract, the hepatic artery, portal vein and hepatic veins before living donor transplantation. Methods and materials: MRI (1.5 T) was performed in 15 patients, including MR cholangiography, T2 weighted fat-suppressed sequences, T1 weighted fat-suppressed sequences before and after gadolinium and MR angiography with gadolinium (arterial and venous phase). Results: MR cholangiography permits preoperative detection of abnormalities and anatomic variants of the hepatic biliary tract may complicate resection of the right lobe such trifurcation, dorsocaudal branch of the right hepatic duct that drained into the left hepatic duct or into the common bile duct (1 case). MR angiography reveals anatomic variant such repositionned right hepatic artery (1 case), abnormality of the portal vein such trifurcation and left portal vein from anterolateral right portal vein (1 case) and common trunk of the right and middle hepatic vein. Segmental arteries anatomy cannot be evaluate. The time required to perform MR examination is 25 minutes. Conclusion: Preoperative MR Imaging helps evaluate, in one time, bile duct anatomy, vascular anatomy and liver parenchyma. MRI may obviate digital substraction angiography for arterial trunks, portal veins and hepatic veins study but not for segmental arterial study.

Quantification of hepatic iron concentration using magnetic resonance imaging J.M. Alustiza 1 , A. Castiella 2 , J. Artetxe 1 , C. Agirre 1 , P. Otazua 3 , J.I. Emparanza 1 , J. Barrio 4 , M. Garcia Bengoechea 1 , M. Group for the study of hemochromatosis 1 ; 1 San Sebastian/ES, 2 Mendaro/ES, 3 Mondragon/ES, 4 Irun/ES Purpose: To validate the capacity of magnetic resonance imaging (MRI) to quantify hepatic iron concentration (HIC). Methods and materials: Between April 99 and March 2001, chemical measurement of HIC (liver biopsy) and subsequent liver MRI were prospectively obtained from 96 patients with no previous knowledge of the clinical or analytical data of the patients. Following Dr. Gandon's method (Rennes, France), MRI examinations included four gradient echo sequences (T1 -120 ms/4 ms/90°(TR/TE/Flip), PD -120/4/20°, T2 -120/14/20° and T2* -120/21/20°) and one spin echo sequence (TR 300 ms/TE 12 ms). The signal intensity liver/muscle ratio (L/M) was measured for each sequence and correlated with HIC values. Results: According to HIC, 56 patients were normal (< 36 mmol/g), 24 with hemosiderosis (HIC < 36 mmol/g and < 90 mmol/g), and 16 with hemochromatosis (HIC > 90 mmol/g). A clasification tree of MRI measurements was used to select the L/M with greatest discriminatory power for each group of patients: Normal: T2 ≤ 0.72, hemosiderosis: T2 < 0.72 and PD ≤ 0.49, hemochromatosis: PD < 0.49. 88.5 % of patients were correctly classified. The HIC was estimated in MRI by applying a linear regression analysis with T2 and PD L/M with a good correlation (r = 0.89). For an estimation on MRI of < 50 mmol/g the negative predictive value for hemochromatosis is 100 %, for an estimation > 100 mmol/g the positive predictive value for hemochromatosis is 100 %. Conclusion: MRI may be an excellent tool to determine HIC.

Quantification of liver metabolites with 31 P magnetic resonance spectroscopy B. Norén, P. Lundberg, M. Ressner, Ö. Smedby; Linköping/SE Purpose: Phosphorus 31 magnetic resonance spectroscopy offers a non-invasive way to study liver metabolism. Previous studies have varied considerably in methodology, patient selection and reference methods. The aim of this study was to develop a quantification method for liver metabolite concentrations. Material and methods: Nine patients with histopathologically proven diffuse liver disease and 12 healthy individuals were examined in a 1.5 T MR scanner (GE Signa Horizon Echospeed). The spectroscopic quantification procedure included:

(1) Determination of optimal depth for in vivo measurements; (2) A coil specific sensitivity map to calculate corresponding correction factors for signal loss; (3) Selected slice and liver volume ratios were determined; (4) Spectra were analysed in the time domain using MRUI software. Results: Compared with the control group, the patients had significantly lower concentrations of phosphodiesters and ATP-(p < 0.05, Wilcoxon rank sum test). There was also a tendency, although not significant, towards higher concentrations of phosphomonoesters in the patient group. Compared with previously reported concentrations in healthy controls, relatively high concentrations were obtained using the slice filling correction factor, particularly for phosphodiesters. When normalising the ATP-resonance to previously reported concentrations of 2.5 mmol, the scaled concentrations were similar to previously reported results. Conclusion: This study has confirmed that absolute concentration measurements of phosphorus metabolites in the liver are feasible. Overall concentrations tend to be somewhat over-rated, but after scaling the results agreed well with those in previous studies. The technique demonstrates some differences between patients and healthy subjects.

Purpose: The goal of the study was to determine the value and capability of MRI without and with application of contrast medium (Gd-DTPA) in the evaluation of recurrent rectal carcinoma as well as to compare CT and MRI sensitivity for detection of mentioned lesions. Methods: 95 patients after resection of rectal cancer underwent pelvic examination on 1.5 T MRI unit Siemens Magnetom SP 63-4000 by use of the routine protocol consisted of T1W axial and coronal planes, T2W axial and sagital planes and axial or sagital plane after application of Gd-DTPA as well as computerized tomography (CT) examination. Results: All patients (pts) underwent different surgical procedures: Milles procedure was done in 65 pts (68.4 %), Dixon procedure in 19 pts (20 %), Harrtman procedure in 4 pts (4.2 %), Maydl procedure in 3 pts (3.2 %), and local tumor excison in 4 pts (4.2 %). Before MR examination 23 pts (24.2 %) were treated with irradiation therapy. Reccurent tumor were detected in 64 pts (67 %). Gadolinium application enabled clear demarcation of the recurrent tumor tissue and surrounding tissues and organs. Parallely performed CT examination detected less then 80 % of detected recurrent tumors by MRI. Conclusion: Gd-DTPA enhanced MRI provided high sensitivity for detection of recurrent rectal carcinoma and evaluation of local tumor extension. MRI showed better diagnostic accuracy for interpretation of complete pelvic status in early and late postoperative as well as in post-irradiation period.

Radiologic-pathologic correlation of obstructive colitis K. Hayakawa, S. Kubo, T. Morimoto, S. Mukaihara, T. Shimada, K. Takasu; Kyoto/JP Purpose: Ischemic colitis proximal to an obstructing colon carcinoma has been termed obstructive colitis or colitis and antecedent carcinoma. These patients may present with acute abdominal symptom with sudden lower abdominal pain, nausea and vomiting. Five cases with pathologically proven obstructive colitis were retrospectively reviewed and the radiological findings were correlated with the pathological features. Material and method: The patients consisted of four male and one female patients and their ages ranged from 58 to 81 years. Result: The obstructing lesions were all advanced colon carcinoma at transverse (N = 2), descending (N = 1), sigmoid colon (N = 1) and rectum (N = 2). The pathological study showed the two types of obstructive colitis, which comprised ischemic colitis-like changes (N = 4) and simple ulcer-like change (N = 1). On imaging study, the ischemic colitis type showed a proximal thumb-printing bowel loop on barium study and edematous submucosal thickening and a pericolic vascular engorgement and a thickening of an adjacent fascia on CT, which may cause overstaging of colon carcinoma. The simple ulcer type showed a proximal punched-out ulceration with distal apple core stenosis on barium study and a linear stranding aound the colon on CT. The differential diagnosis mimicking obstructive colitis comprised ischemic colitis, drug-induced colitis, enteroheromorrhagic colitis and also far-advanced colon cancer. Conclusion: It is very important to be familiar with the imaging findings of these conditions.

Staging of gastrointestinal stromal tumours (GIST) using a combined inline PET-CT scanner G. Barghouth 1 , S. Leyvraz 1 , P. Schnyder 1 , G.K. von Schulthess 2 , G.W. Goerres 2 ; 1 Lausanne/CH, 2 Zürich/CH Purpose: Early evaluation of the role of FDG-PET in combination with CT for the primary staging of GIST. Methods and materials: 8 patients with GIST underwent FDG-PET and CT before treatment with a new tyrosine kinase inhibitor (STI571, Glivec, Novartis, Basel, Switzerland). All patients were examined on a new combined in-line PET-CT scanner (Discovery LS, GEMS). Results: In all patients the known abdominal tumour masses and metastases were detected with good anatomic resolution by CT. FDG-PET revealed information about the biological activity of GIST masses. We found an heterogeneous uptake pattern of FDG with areas of low uptake and high uptake within the same patient and even within the same tumour mass. This heterogeneous metabolic pattern may have a prognostic value. In addition FDG-PET was able to define active regions adjacent to necrotic areas. Conclusion: There is a large difference between the metabolic and anatomic information in GIST patients. We found a large intra-individual range of FDG uptake. Therefore, the functional information provided by PET is complementary to the structural information of CT. Combined PET-CT with perfect alignment facilitates lesion interpretation and may proof useful for the planning of histological sampling. Further clinical evaluation is required to confirm this very early FDG-PET pattern information.

Dynamic scintigraphy of the gastric emptying in the patients after peptic ulcer surgery V.B. Obradovic, A. Afgan, B. Stefanovic, V.M. Artiko, N. Petrovic, B. Davidovic; Belgrade/YU Purpose: The aim was to examine the influence of peptic ulcer surgery on the gastric emptying (GE) pattern. Material: Forty-two subjects were examined -7 healthy volunteers (C) and 35 patients following peptic ulcer surgery (performed at least 6 months previously): 7 Billroth I (BI), 11 Billroth II (BII), 7 BI with the selective vagotomy Harkins 1 (H1) and 10 BII with the selective vagotomy Harkins 2 (H2). Methods: The test meal was 99 Tc-S-colloid labeled and boiled chicken liver in beef stew. Dynamic scintigraphy was performed with gamma camera during 120 minutes (1 frame/60 s). Gastric TA curve was corrected for the radionuclide decay, and the lag phase duration (min) and emptying rates (%) were analysed. Results: The lag phase duration (C 18 min, BI 23 min, BII 13 min, H1 32 min, H2 20 min) was inversely related to GE rates, and the GE pattern was linear in both controls and operated patients, except in BII in which it was exponential. Mean values of the gastric emptying at 30 th , 60 th , 90 th , and 120 th minute were: C -13 %, 34 %, 47 %, 62 %; BI -7 %, 23 %, 40 %, 57 %; BII -29 %, 54 %, 66 %, 71 %; H1 -0 %, 12 %, 25 %, 43 % and H2 -3 %, 19 %, 33 %, 52 %. In relation to C group, GE was slower in BI (p < 0.05), H1 and H2 groups (p < 0.01), and faster in BII group (p < 0.01). Conclusion: Slower GE in operated patients (except BII), could be explained by massive gastric motility disorders (H1, H2) and by decreased anastomotic patency (BI, H1). Faster GE in BII might be due to increased anastomotic patency (large stoma) and lack of the duodenal inhibitory activity.

Pitfalls in virtual colonoscopy G. Luccichenti 1 , F. Cademartiri 1 , L. Nogueira 2 , P. Pavone 1 ; 1 Parma/IT, 2 São Paulo/BR Purpose: To evaluate the common pitfalls occurring during a virtual colonoscopy examination. To identify the ideal protocol for a routine practise of virtual colonoscopy. To explain the drawbacks of a routine Virtual Colonoscopic scan. To enhance the technical aspects needed to perform a higher number of examination with a good quality. Method and materials: 57 patients underwent a spiral CT for virtual colonoscopic evaluation with the following parameters: collimation 3 mm, feed 6 mm, pitch 2 and increment 1 mm in supine position. A second prone acquisition was performed in case of inadequate colon distension. In case of a suspected lesion the second acquisition was performed after contrast media injection. Virtual Colonoscopy examination was performed on a workstation equipped with post-processing software. Results: The patient preparation is the most important aspect of this technique. Fluid was more common in left colon and cecum. Recto-sigmoid junction was difficult to distend in the supine position. In few patient stool avoided a complete examination. In one patient with femoral prothesis metal artifacts were observed. Conclusion: Pitfalls are relatively frequent in routine virtual colonoscopy examination and are mainly due to low spatial resolution, to segmental collapse of the colon and to incomplete colon cleansing.

Possibilities of ultrasound study in mechanical and dynamic ileus V.D. Zavadovskaja, N.G. Zavjalova, I.G. Sinilkin, G.E. Chernyshova, I.I. Ossina; Tomsk/RU Aim of the study: to determine the role of ultrasound study in the differential diagnosis of mechanical and dynamic ileus. Material and methods: 85 subjects with ileus underwent ultrasound study using a SIEMENS "Sonoline-SL-450" machine using 3.5 -5 MHz transducer. Results: Early mechanic acute ileus results in dilated intestinal loops, increased frequency and amplitude of peristalsis waves, moving of the contents based upon brown moving type, preserving the wall normal structure. The process advancing is followed by decreased peristalsis frequency and amplitude, pendulum-shaped moving of the contents, absent wall structureand fluid in the interloop space. Early dynamic acute ileus results in dilated intestinal loops, absence of peristalsis and moving of the content; the wall structure is preserved. The process advancing is characterized by absent peristalsis and content moving, loss of wall structure, occurring fluid in the interloop space.

Ultrasound study may allow to differentiate early mechanic and dynamic ileus based upon peristalsis character and peculiarities of intestinal content moving. Differential diagnosis is less effective when the disease was advancing for a long time.

3D volume assessment of sigmoido-rectal junction cancer F. Cademartiri, G. Luccichenti, P. Pavone; Parma/IT Purpose: Linear measurements are still controversial for the evaluation of tumour response in oncology. Aim of this study is to optimise a protocol for the volumetric assessment of sigmoido-rectal junction cancer before and after radiotherapy. Methods and material: Patients with endoscopic and pathologic diagnosis of sigmoido-rectal cancer underwent spiral CT of the pelvis with the following parameters: collimation 3 mm, pitch 1.5 and increment 1 mm. Air distension was obtained through a Foley catheter. The reconstructed images were sent to a dedicated workstation running on a NT platform equipped with post-processing software (Vitrea 2.0, Vital Images, USA) in order to estimate the volume through manual segmentation techniques. Two experienced radiologists evaluated further information provided by virtual colonography. Results: Patient preparation is the most important aspect of this technique. Optimal colon distension can be obtained in prone position. In all cases the changes of tumour volume after radiotherapy was significative. Conclusion: A technique based on volumetric measurements can be proposed as a new tool for the evaluation of recto-sigmoid junction cancer response.

Imaging of upper digestive tract surgery with spiral CT E. Testempassi sr., A. Fakou sr., P. Kazakidis sr., C. Chatziconstantinou sr., D. Kourousis sr., A. Liaou sr.; Athens/GR Purpose: Radiologists are confronted daily with images of patients who have undergone surgical procedures. The purpose of this exhibit is to illustrate the most commonly performed surgical procedures for upper digestive tract diseases and their appearance on CT images of the abdomen. Materials and methods: We prospectively studied the abdominal CT images of 23 patients, who had previously undergone upper digestive tract surgery. The examination protocols were modified according to the clinical history of the patients, the previously performed operative procedure and the time from the operation. 5 patients had plain CT without oral contrast media, 10 patients had CT with oral contrast medium and 8 patients performed hydro-CT of the upper gastrointestinal tract after iv injection of glucagon and iv administration of contrast medium. Results: We present most of procedures and operation types used in upper gastrointestinal tract surgery such as total gastrectomy, subtotal gastrectomy, fundic resection, Billroth II anastomosis, variations of Roux-Y loop procedure and Whipple's operation. Schematic drawings of the procedures and postoperative CT anatomy of the stomach are depicted. Conclusions: The familiarity with the normal CT anatomy of the stomach is very significant in its postoperative evaluation and in the differentiation of normal and abnormal conditions. Hydro-CT is helpful in the better visualization of remaining stomach and anastomotic loops.

US and CT appearences of lipodystrophy associated with a protease inhibitor in human immunodeficiency virus-infected patients N. Gandolfo 1 , P. Gazzo 1 , C. Martinoli 2 , G. Serafini 1 , L.E. Derchi 2 ; 1 Pietra Ligure/IT, 2 Genova/IT Purpose: A new syndrome of acquired lipodystrophy, insulin resistance, and dyslipidemia was recognized in patients with HIV infection, particularly in those treated with protease inhibitors. The purpose is to describe the US and CT appearances of lipodystrophy syndrome and discuss a possible differential diagnosis. Materials and methods: We evaluated three patients who were receiving HIV-1 protease inhibitor (PI) indinavir (800 mg three times daily) in addition of standard antiretroviral regimen of zidovudine (250 mg twice daily) and lamivudine (150 mg twice daily). The mean time of initiation of PI therapy was 20 months. Patients were underwent to radiological imaging for abdominal cramping and pain. Abdominal US and helical CT were been performed in all patients. Biochemical and clinical data were integrated. Results: Within five to nine months after the initiation of indinavir, fat wasting of the face, arms, buttocks and legs developed. There was concurrent central obesity and enlargement of the cervicodorsal fat pad (buffalo hump). Clinically, muscle mass and strength were normal. US and CT confirmed abnormal fat proliferation throughout the abdomen in a perivisceral distribution, with marked accumulation of fat in perirenal and perirectal spaces. In comparison, there was little subcutaneous fat. Imaging was negative for abdominal organomegaly, mass or ascites. In one patient colon biopsy was negative for subclinical inflammation. Hypercholesterolemia (n = 2), hypertriglyceridemia (n = 3), and insulin resistance (n = 2) were associated. Conclusion: The incidence of HIV-related lipodystrophy syndrome is likely to increase with current treatment regimens and radiologist should be aware of the features of this condition.

Ultrasonography and computed tomography findings in four cases of complicated Meckel's diverticulum S. Costa, T. Ripollés, F. Delgado, M. Agramunt, M.J. Martínez; Valencia/ES Purpose: To present four complicated Meckel's diverticulum in adult patients diagnosed with ultrasonography and computed tomography imaging. Methods and materials: We present four patients with nonspecific clinical presentation that underwent sonographic and/or helical computed tomographic (CT) study with oral contrast media. Pathologic correlation was obtained in three patients and surgical correlation in one. Results: The median age of the four patients with complicated Meckel's diverticulum was 44 years old. Three patients were male and one were female. All four patients complained acute symptoms. Ultrasonography and CT showed: in two patients, tubular and concentrically layered structures located far from the cecum and Meckel's enteroliths, and in other patient, cystlike Meckel's diverticulum was seen. One patient had a multilobed shape Meckel's diverticulum, seen on ultrasonography. Conclusion: Diagnosis of Meckel's diverticulum may be difficult. Nuclear medicine and barium studies should be performed but ultrasonography and CT may be the first modality chosen to evaluate complicated Meckel's diverticulum. CT and ultrasonography can be useful detecting Meckel's enteroliths, and oral contrast material administration can be helpful to identify the ileal dependence of the diverticular structure, besides the possibility of multiplanar reconstuctions with helical CT.

The role of ultrasonography in the management of acute colonic diverticulitis M. Agramunt, S. Costa, T. Ripollés, M.J. Martínez, S. Picó; Valencia/ES Purpose: To evaluate the role of ultrasonography (US) in the diagnosis and management of the acute episode of diverticulitis and its capability to predict secondary complications during follow up. Methods and materials: We review 221 patients admitted in our hospital with the initial diagnosis of diverticulitis over last 5 years. Diverticulitis was divided as simple and complicated considering the latter when abscess and/or extraluminal air were observed. Results: The sensitivity of US was 86 % in 90 proven cases at operation and 94 % in total cases. Ten of the 11 negative false had fecal peritonitis at surgery. Of 26 patients with emergency surgery, 20 (77 %) had complicated diverticulitis on US, compared with 53 (31 %) of 169 who had conservative treatment (p < 0.0001). After follow up 54 of 169 patients had secondary complications: 23 (43 %) of these had initial complicated diverticulitis on US compared with 31 (27 %) of 115 patients without complications (p < 0.05). Conclusion: US is a safe technique for the evaluation of patients suspected of having diverticulitis. Complicated diverticulitis findings on initial US may predict a poor outcome in acute and later phase.

Imaging Results: In respects of histopathologic findings, primary duodenal tumors reported in this study consist of adenocarcinoma, villous adenoma, malignant lymphoma, leiomyosarcoma, carcinoid tumor, lipoma and polyp. The tumors locally invasive to duodenum mainly originate from pancreatic head, colon or ampulla of Vater. Other space-occupying lesions include ectopic pancreas, intramural hematoma of duodenum, and pancreatitis. The CT and double-contrast barium examinations depicted intraluminal tumor growth in adenocarcinoma, ectopic pancreas, adenoma, metastatic tumors and polyp, resulting in partial or complete intestinal obstruction. Intramural space-occupying lesions were noted in malignant lymphoma, leiomyosarcoma, even hematoma. In these cases, the mucosal pattern appeared to be preserved. Extrinsic compression and/or invasion on the duodenum may result from colon cancer, pancreatic cancer or inflammatory mass due to pancreatitis. Tumor infiltration through serosa of duodenum and fistula formation between colon cancer and duodenum was also seen in a case. Adenocarcinoma of ampulla of Vater may lead to obstruction of biliary tract outflow, which was nicely shown on cholangiograms. A case of intestinal intussusception due to lipoma in duodenum is also demonstrated. Conclusion: In this report, we have demonstrated the characteristic features of space-occupying lesions in duodenum including tumors and tumor-like lesions.

Purpose: To review the spectrum of CT findings in acute pancreatitis complicated by intestinal involvement. Materials and methods: We reviewed the files of 19 patients with diagnosis of acute pancreatitis complicated by intestinal involvement. Results: The second and third part of the duodenum was involved in 4 patients. Inflammatory thickening of the wall with subsequent stenosis and gastric dilatation was noted in two patients. A duodenopancreatic fistula was present in two. Small bowel abnormalities were seen in 3 patients. In one patient ascites and paralysis was associated with diffuse thickening of the small bowel wall with increased contrast enhancement. In another patient prolonged hypotension resulted in shock bowel. A third patient developed an inflammatory mass extending into the mesenterium and bowel wall and resulted in small bowel stenosis with obstruction. Colonic involvement was noted in 12 patients. The left colon was involved in 10 patients, the right colon in one. In one patient diffuse colonic involvement was noted. Infected pancreatic necrosis resulted in pancreatocolonic fistula in one patient. Ischaemic colitis and colonic necrosis with perforation was seen in one patient respectively. Retroperitoneal and (peri)colic inflammation resulted in colonic stenosis in nine patients. In four of them pancreatic abscess with compression on the colon was noted. Conclusion: Intestinal involvement is an uncommon complication of acute pancreatitis. CT scan may accurately demonstrate intra-and peripancreatic inflammation and also extension through the intestinal tract. Our experience illustrates the diverse types of intestinal involvement that may occur. Colonic involvement was the predominant presentation.

Endorectal ultrasound in assessment of pararectal lymph nodes in rectal carcinoma L. Florescu, V. Popita, S. Petcu, I.-R. Ivan, I.-R. Negrea, C. Florescu; Cluj-Napoca/RO Purpose: The aim of this study was to show the value of Endorectal Ultrasound (EUS) in early diagnosis of rectal carcinoma and the correlation between T1 tumors and pararectal lymph nodes involvement.

The study included 176 patients, 114 males and 62 females, mean age 49 years (range 32 to 65 years) who were examined by abdominal ultrasound, colonoscopy, endorectal ultrasound, and CT scan. The study was performed between 1996 -2000. Results: Colonoscopy was performed in 176 patients, 96 patients of them were diagnosed with upper rectal carcinoma and 80 patients with lower rectal carcinoma. 176 patients were examined by abdominal ultrasound, 40 patients (22.72 %) had liver metastasis and they were not examined by EUS. Endorectal ultrasound was performed at 136 patients (77.27 %), pararectal lymph nodes between 3 -9 mm diameter were detected in 41 patients (30.14 %) and were correlated with T1 carcinomas biopsy-proven, and 95 patients (69.85 %) had pararectal lymph nodes over 10 mm diameter. The sensitivity of EUS for T1 tumors was 74 % and the specificity 89 %. The accuracy for lymph node staging was 83 %. CT scan was performed in 86 patients (including the 41 patients diagnosed by EUS), pararectal lymph nodes over 10 mm diameter were detected in 45 patients. Conclusion: EUS is superior to CT scan in the diagnosis of pararectal lymph nodes and their size was the most reliable parameter to determine tumor involvement. T1 tumors could be assessed with a high degree of accuracy using EUS.

Importance of radiology on the treatment of morbid obesity F. Matute Teresa, B. Gonzalez Garcia, P. Diego Rey, M. Bertolez Cue, A. Mañas Hernandez; Madrid/ES Objectives: With our study we demonstrated the relevance of radiology, fundamentally the studies with oral contrast (oesophagogastroduodenal transits), in the postoperative evaluation of morbid obesity, its complications and monitoring. Material and method: We analysed the radiological studies of 508 patients, with morbid obesity who had undergone bariatric surgery in the service of Surgical Pathology of the Hospital Clínico Universitario San Carlos (Madrid) between January of 1990 and May of 2001, the types of surgery performed were: 254 BVG, 35 RVG, 118 Torres-Oca, 79 Salmon and 22 that are included in other types of surgery like the Scopinaro, Capello, inflatable or silicone bands. All of them underwent a oesophagogastroduodenal transit with oral contrast, immediately and at 3, 6, 12, 18 and 24 months post-operatively and then annually. In some cases other tests like ultrasound or the CT was necessary for the best evaluation of the complications. Results: Through the radiological examinations performed, complications were detected in 24 % of the cases; early complications like dehiscence of sutures and obstruction and late comlications like fistulas, stenosis, inclusion or laxity of the band, and expansion of the gastric surplus.

The radiological studies with oral contrast are very important in the multidisciplinary work that it is necessary in the treatment of morbid obesity, for the registered overhaul and detection of complications after surgery.

Enteroclysis appearances in intestinal tuberculosis -a pictorial essay A. Batra 1 , A.K. Agrawal 2 ; 1 New Delhi/IN, 2 Varanasi/IN Purpose: Enteroclysis remains the modality of choice to determine mucosal changes associated with intestinal diseases and to provide dynamic information regarding bowel peristalsis or causes of partial intestinal obstruction. The present study is a comprehensive illustration of the features of intestinal tuberculosis as seen on enteroclysis. Methods and materials: A retrospective analysis of 48 enteroclysis studies of patients proven to have intestinal tuberculosis on basis of either histopathological evaluation (n = 23), fine needle aspiration (n = 18) and follow-up on treatment (n = 7) was done. All the patients had undergone enteroclysis by intubation with the Herlinger modification of the Bilbao-Dotter tube and subsequent instillation of barium and methylcellulose. Results: The main clinical indications for an enteroclysis examination were abdominal pain (n = 13), abdominal pain with moving lump (n = 29), small bowel diarrhea (n = 2) and lower intestinal bleed (n = 2). Of the 48 patients, isolated ileocaecal (n = 19), jejunal (n = 8), ileal (n = 5) involvement was seen in 66.67 % patients. Multiple site involvement was seen in 33.33 %. Enteroclysis patterns seen in various combinations were ileocaecal changes including retraction, ulcerations, nodularity and patulous ileaocecal valve (52.1 %); short segment strictures (41.67 %); mesenteric thickening (31.25 %); ulcerative lesions (31.25 %); focal ulceronodular lesions (20.83 %); long strictures (18.75 %); diffuse mucosal ulcerations and nodularity (8.3 %). GB is the most popular operation in the treatment of MO in the world. X-ray examinations of the patients after GB are important investigations in postoperative period. Material and methods: Between 1992 and 2001 96 patients with MO were operated on GB (age from 18 to 62 years). Weight of the patients was from 130 up to 290 kg, on the average (210 ± 18) kg, BMI > 60 kg/m 2 . X-ray were performed pre-operative, in early postoperative time (7 -10 days) and twice during the first year. We used the standard method with barium. X-ray provided the possibility to evaluate the form, volume and situation of stomach. Special attention was paid to the oesophagogastric junction and deformations of stomach. Results: After GB in proximal part of stomach visualized small pouch with volume approximately 15 -20 ml, round, with stoma diameter app. 11 ± 1 cm. Full emptying of this small pouch was observed after 22 ± 3 min in average. Conclusion: X-ray evaluates the status of the stomach; shape, sizes, outlet of small stomach and emptying rates in patients with MO after GB. X-ray is an effective method of investigation of upper GI-tract in morbidly obese patients.

Static and functional MR colonography after application of an hepatobiliary MR contrast agent: Initial results with Gd-BOPTA M.V. Knopp 1, 2 , F.L. Giesel 1, 2 , J. Radeleff 2 , H. von Tengg-Kobligk 1, 2 ; 1 Bethesda, MD/US, 2 Heidelberg/DE Purpose: Cross-sectional colonography with CT or MRI is using aboral or oral administration of a contrast material and frequently additional i.v. medication in order to relax musculature. These approaches have focused on imaging pathomorphological findings. We studied the potential use of a hepatobiliary excreted MR contrast agent for intraluminal enhancement of the colon and investigated its potential use especially for functional assessment of colonic motility. Material and methods: Gadobenate Dimeglumine (Gd-BOPTA, Multihance, Bracco SpA, Milan) is a Gd-chelate that exhibits partial hepatobiliary excretion. A standard dose of 0.1 mmol/kg bw was used. After an initial MRA, abdominal 3D GRE images were obtained at several time points between 12 and 60 h. post injection. No contrast enema, medication or other patient preparation was given. Qualitative and quantitative analysis of the multiphasic studies were performed. Results: Intense, homogenous contrast enhancement within the colon was observed within 24 h post injection (p.i.) in all subjects. The strongest signal intensity in the colon was detected at 16 -50 h p.i. Physiological propulsion of the colon could be visualized. The quality of enhancement was sufficient to enable 3D processing for volume rendering and virtual colonoscopy. Conclusion: This exhibit will present the concept of bile-tagging for functional MR colonography after exclusive use of an i.v. MR contrast agent with partial hepatobiliary excretion. The diagnostic potential, limitations and physiological aspects were addressed.

Oesophagectomy: Early and late complications at digital fluoroscopy P. Giusti, E. Neri, I. Bargellini, R. Bachini, S. Giusti, C. Bartolozzi; Pisa/IT Purpose: To evaluate the role of digital fluoroscopy in the detection of early and late complications after surgical treatment of oesophageal cancer. Materials and methods: From January 1995 to April 2001, 389 consecutive patients were evaluated on Digital Fluoroscopy (DF) (Clinodigit, Italray, Italy), after surgical treatment for oesophageal cancer (total or subtotal esophagectomy). All patients were studied seven days and three months after surgical intervention to evaluate early and late complications. Results: Early studies with single contrast esophagograms revealed dehiscence of the surgical anastomosis in 20 cases and cervical fistulas in 8 cases. Double contrast technique performed three months after surgery demonstrated recurrent tumour in 53 patients and fistulas in 28 patients. Conclusion: In our series oesophageal DF allowed an early diagnosis of complications and a complete oesophageal evaluation in all cases leading to appropriate further intervention only when required. The exhibit presents the patterns of early and late complications of oesophagectomy showed at DF.

CT evaluation of colorectal perforation in patients with chronic renal failure on hemodialysis K. Furuya, I. Sakino, T. Inakura, M. Nakamoto, Y. Iso, A. Nagamatsu; Kitakyushu/JP Purpose: With the increasing number of hemodialysis patients, radiologists should be aware of the associated complications in patients with chronic renal failure on hemodialysis. Colorectal perforation is one of the severe gastrointestinal complications of long term hemodialysis patients, often be lethal because of the difficulty of early diagnosis. The purpose of this exhibit is to show the helical CT findings of colorectal perforation in them and to discuss the diagnostic value of helical CT.

The findings of Helical CT and medical records of 9 hemodialysis patients with colorectal perforation were examined. Pathological study was also done. Result: Sigmoid colon was most common perforation site with up to 5 patients. Helical CT could detect small amounts of extraluminal gas adjacent to the perforated intestine, as well as gas in the subphrenic space or beneath the abdominal wall. Other CT findings included focal fluid collection, abscess or feces, and increased fat attenuation adjacent to the perforated intestine. One case showed focal thinning of colonic wall and edematous colon distal to it, indicative of perforated site. Pathological study showed segmental necrosis of the affected intestine without vascular thrombus or diverticulitis, indicating insufficient microcirculation of intestine due to abrupt blood pressure change during HD cause the intestinal ischemia, resulting in the colorectal perforation in patients on hemodialysis. Conclusion: Helical CT, especially with intravenous contrast media, provides precise radiological informaitons for urgent therapy in patients on hemodialysis who suffer colorectal perforation. To assess the role of high-resolution ultrasound (HRUS) versus histology in small bowel intestinal ischemia after strangulating obstruction. Method and materials: The 2 mechanisms of strangulated small bowel obstruction (volvulus; adhesions) were experimentally induced in 12 intestinals segments in 4 piglets. Different grades of severity were created. Percutaneous and peroperative HRUS were used to examine the intestinal wall after 1 and 5 hours. The results were compared with histologic results. Results: In subtle or moderate strangulations, histology and HRUS demonstrated early signs of ischemia injury as thickening of the mucosae-submucosae complex (> 4 mm). This aspect resembles a venous ischemia. In severe strangulations, HRUS showed the lack of mucosae-submucosae differentiation that corresponded to the necrosis of the mucosae and submucosae with hemmoragic infiltration at histology. Conclusion: HRUS has the ability to detect ischemia injury and can be use in the early diagnosis of ischemic lesions of small bowel obstruction by strangulation.

Differentiation of hyperplastic pancreatitis and pancreatic carcinoma by means of us, CT and MRI: correlation with pathological findings V.S. Pruchansky, B.A. Minko, L.B. Alieva; St. Petersburg/RU Purpose: To estimate the possibilities of radiologic methods in differentiation of hyperplastic (pseudotumorous) pancreatitis and carcinoma of the pancreas. Methods: 75 patients (38 male and 37 female, aged 20 -72, middle age 51.2) with volumic enlargement of the pancreas were examined with transabdominal ultrasound (US), CT and 1.5 T MRI. Clinical findings, course of the disease, all means of visualization added to the results of the pancreas biopsy were considered in diagnosis affirmation. Results: Hyperplastic pancreatitis was revealed in 12 patients, pancreatic carcinoma in 63 patients. The leading sign of pseudotumorous pancreatitis was diffuse enlargement of the pancreas which was observed in 8 patients. US and CT in the majority of cases revealed a decrease of parenchymal echogeneity and density. MRI showed an increase of signal intensity within T2 imaging. The leading sign of pancreatic carcinoma was an appearance of focal formations within the head of the pancreas which was observed in 65 % of cases. US and CT revealed the abnormal structure of the pancreas due to the areas of high density. MRI showed a high signal in both T1 and T2 imagings. On the way to the accurate diagnosis we found it very important to reveal indirect signs of malignancy within the pancreoduodenal area. Application of the contrast media (magnevist) was rather useful in pancreas exposition at MR images. The whole spectrum of radiologic means with fine-needle biopsy of the pancreas provides an accurate diagnosis in 90 %.

Radiologic features of laparoscopic adjustable silicon gastric banding for the treatment of morbid obesity I. Khettab, C.A. Cuenod, N. Siauve, J.-L. Picoche, F. Zinzindohoue, J.-M. Chevallier, P.-H. Cugnenc, G. Frija; Paris/FR Purpose: To specify the contribution of imaging in laparoscopic adjustable silicon gastric banding (LASGB), and describe the radiologic appearence of postoperative complications. Materials and methods: 500 consecutive patients (438 women and 62 men, mean age 40.4, range = 16 -66 years) underwent LASGB between april 1997 and june 2001 for morbid obesity, after preoperative ultrasound of the liver and barium upper gastrointestinal series. Water-soluble contrast series were performed on day 1 after surgery to document the band position and exclude perforation, and after 3 -4 weeks to tighten the band under fluoroscopy guidance. Results: Risk factors were preoperatively identified in 35 patients [hypertrophic left liver (20) , diverticulum cardia (1), hiatal hernia (13), stomach cancer (1)]. Early and late complications occured in 73 patients and included (perforation (4), dilated pouch (54), gastric necrosis (1), disconnection of the tube (6), port-site infection (8). Conclusion: Imaging plays an essential role by detecting the risk factors before surgery, and the early and late complications after surgery.

Value of water-soluble contrast in evaluating clinically small bowel obstruction A. Aulin, J.-P. Tasu, J. Sales, E. Kulh, L. Rocher, A. Miquel, F. Gayral, M. Blery; Le Kremlin Bicêtre/FR Introduction: This study seeks to determine whether a 12-hour abdominal radiograph performed after oral gastrografin is a reliable indicator for nonoperative treatment in patients with a clinically small bowel obtruction. Materials and methods: Patients who received a gastrografin transit time (GGTT) study for intestinal obstruction between january 1995 and december 2000 were included retrospectively. Serial plain abdominal radiographs were taken. If the constrast was in the colon within 12 hours, then the test was negative. Results: A total of 95 patients were reviewed. Contrast reached the colon within the 12 hours in 85 (89.5 %) patients, and all of these were managed nonoperatively. For the 10 patients in whom the test was positive, surgery was perfomed and proved a small bowel obstruction. Conclusion: GGTT studies are of significant help in the clinical management of patients suspected to have a small bowel obstruction. GGTT are cost effective, safe, and clinically useful when attempting to treat patients conservatively. Removal of small bowel obstruction in a lot of cases could be due to effects of gastrografin hyperosmolarity.

Spiral CT findings in post-surgical abdomen: Morphologic aspects and complications A. Rimondini, A. Morra, M. Pravato, R. Pozzi-Mucelli; Trieste/IT Purpose: To describe the CT appearance of normal postoperative findings and complications following the most common GI surgical procedures. Materials and methods: 78 patients who underwent abdominal surgery for gastrointestinal diseases were examined with enhanced spiral CT within 15 days. A second CT examination with the same scan parameters was performed within 12 months. Results: The normal postoperative findings for the different types of pancreatic resections (12 cases), gastric resections (14 cases), colic resections (52 cases) will be presented. Furthermore the early (37 cases) and late (16 cases) complications will be illustrated. Conclusion: Spiral CT is a very useful modality in the evaluation of patients who underwent abdominal surgery, for its efficacy to show the new anatomic distribution of intraperitoneal organs after GI tract surgery. This is very important for the radiologist, especially to distinguish normal or paraphysiologic findings from postoperative abnormalities. Spiral CT allows to detect and graduate the early complications, such as fluid collections, acute pancreatitis, anastomotic leakage, extraabdominal complications, to establish the incorrect position of drainages, to show late complications such as bowel obstructions, metastasis or local recurrences and to distinguish them from normal perianastomotic appearance. In this study we find that MPRs are very useful, particularly in the evaluation of the extension of the fluid collections and to differentiate them from bowel loops. In conclu-

sion we emphasise the role of spiral CT in post surgical abdomen, for its diagnostic value and for its usefulness in interventional procedures, such as drain positioning into abdominal abscesses.

Flat neoplastic lesions of the colon: Its different radiological features with endoscopic and surgical correlation M.M. Buzzi, S. Ballester, M. Gil Pomar, A. Di Sanzo, C. Rostagno, M.A. Acha; Buenos Aires/AR Purpose: To describe the radiological features of flat neoplastic colonic lesions. Materials and methods: We retrospectively reviewed all (34560)barium enema examinations performed at our institution in the last 10 years. Results: Of those, 2938 (8 %) were diagnosed as polypoid lesions. From these, only 60 (2 %) resulted flat neoplastic colonic lesions, defined as those tumors that never grow beyond the level of normal surrounding mucosa. They are infrequent and difficult to detect. The great majority are asymptomatic, and incidentally diagnosed during a barium enema exam. Their size varies from 2 to 10 cm, presenting different radiological features; from coin like lesions with smooth or irregular surface showing a central cleft or depression, to those widely extended with lobulated contours and a granular or nodular surface pattern. 85 % resulted benign: tubular adenomas, villous adenomas or tubular-villous adenomas. Conclusion: Barium enema exam is a useful method for detecting this type of lesions, and it's important as a screening method, also useful for surgical planning, because they are sometimes difficult for the surgeon to detect by manual palpation.

Virtual colonoscopy: Single vs. multislice CT P.M. Carrascosa sr. 1 , C.M. Capuñay jr. 1 , R. Castiglioni sr. 1 , S. Chandra 2 , D.D. Matthews 2 , J.M. Carrascosa sr. 1 , G. Sangster 1 ; 1 Buenos Aires/AR, 2 Cleveland, OH/US Purpose: To evaluate the benefits of multi-slice CT (MSCT) versus single-slice CT (SSCT) in the detection of elevated lesions with Virtual Colonoscopy (VC) and to compare colonic distention and respiratory artifacts of the two scanners. Materials and methods: A total of 177 patients with history of colorectal cancer or any coloproctologic symptoms such us bleeding or constipation were studied. MSCT (n = 115, Marconi Medical Systems, Highland Heights, US) and SSCT (n = 62, Marconi Medical Systems, Highland Heights, US) were performed in supine and prone positions. Findings were evaluated by different approaches: (1) Presence of elevated lesions. This group was subdivided into 3 groups based on the diameter of the lesions: (1a) < 5 mm; (1b) between 5 -9 mm; (1c) > 9 mm. These lesions were corroborated with conventional colonoscopy (CC). (2) Grade of colonic distention. (3) Presence of respiratory artifacts. Results: The sensitivity and specificity was 100 % both in SSCT and MSCT for lesions > 9 mm. Suboptimal colonic distention was more frequent in SSCT in 40 % (25 of 62 patients) than MSCT in 15 % (21 of 115 patients). Similar results were found with regards to the respiratory artifacts: SSCT 64.5 % (40 of 62 patients) and MSCT 10 % (11 of 115 patients). Conclusion: Even though there were no differences between SSCT and MSCT in the detection of lesions > 9 mm; MSCT showed significantly fewer respiratory artifacts as well as suboptimal colonic distention due to its faster acquisition speed.

Dynamic MRI and angiogenesis on the colorectal tumors N. Tuncbilek, E. Unlu, S. Altaner, M.H. Karakas, B. Cakir; Edirne/TR Purpose: Angiogenesis, de-novo vessel formation originated from preexisting vascular network plays the key role in tumor progression and metastasis. The purpose of the study is to quantitatively evaluate the corelation between dynamic MR contrast enhancement parameters and microvessel densities (MVD) of malignant colorectal tumors. Materials/methods: 20 patients (ages between 30 and 77), with known colorectal malignancies were investigated with the gadolinium-enhanced 3D-FLASH MR imaging, as the part of their preoperative work-up. The related pathologic specimens were immunohistochemically stained with Factor VIII, and MVD measurements were subsequently performed. Results: The evaluation of time-signal intensity curves obtained from the area of maximum enhancement were as follows: signal maxima in first minute and subsequent decrease in 10 patients; early enhancement and subsequent plateau formation in 6 patients; enhancement without peak in 4 patients. Significant corelation was found between the maximal percent changes in contrast enhancement and MVD's for the first minute following the injection of paramagnetic contrast (r = 0.693; p = 0.001), whereas no significant corelation was found between maximum change in signal intensity and MVD's (r = 0.285; p = 0.223). In the qualitative analyses, the acceleration rate of the time-intensity curve were found to be significantly related to MVD's (r = 0.807; p = 0.000). Discussion/conclusion: Our study confirms the role of the MVD in the initial rate of MR contrast enhancement and the delineation of tumors. The percent enhancement rate in the fist minute and the rate of time-signal intensity increase may help to predict the tumoral MVD. Above parameters may also be used in therapeutic planning as prognostic indicators.

Malignant peritoneal mesothelioma: Imaging findings in eight patients M. Kebapci, E. Vardareli, M. Acikalin, R. Ozkan, T. Kaya; Eskisehir/TR Purpose: Malignant peritoneal mesothelioma is an uncommon primary neoplasm. We retrospectively analysed the imaging findings of eight malignant peritoneal mesothelioma. The imaging features, pathology, and differential diagnosis of malignant peritoneal mesothelioma were discussed. Methods and materials: Imaging findings of the abdomen in eight patients with a histologically proven diagnosis of peritoneal mesothelioma were reviewed. There were 5 women and 3 men, with a median age of 48 years (range 40 -55 years). Radiologic studies consisted of computed tomography (7) and sonography (1). Imaging findings for all cases were analysed for evidence of tumor involvement in the peritoneum, mesentery, lymph nodes, and lower pleural space, and for ascitic and pleural fluid. Histologic specimens were retrospectively examined and mesotheliomas were classified as epithelial (3 solid, 5 tubopapillary form) types. Results: Ascites was found in eight patients, peritoneal masses in five patients, small peritoneal nodules in four patients, parietal peritoneal thickening in six patients, thickened mesentery in seven patients, pleural fluid in three patients and retroperitoneal lymph nodes in three patients. Conclusion: Imaging findings of peritoneal mesothelioma are nonspecific. Malignant peritoneal mesothelioma should be included in the differential diagnosis of diffuse or localized peritoneal disease, such as carcinomatosis peritonei, tuberculous peritonitis, leiomyosarcomatosis, metastases, and retroperitoneal tumors.

Virtual colonoscopy in the diagnosis of polyps in the paediatric population C.M. Capuñay jr. 1 , P.M. Carrascosa sr. 1 , A. Bou Khair 1 , N. Castagnino sr. 1 , D.D. Matthews 2 , S. Chandra 2 , I. Ninomiya 1 , J.M. Carrascosa sr. 1 , G. Sangster 1 ; 1 Buenos Aires/AR, 2 Cleveland, OH/US Purpose: To demonstrate the advantages of virtual colonoscopy (VC) for the diagnosis of polipoid lesions in children. Material and methods: Forty-five patients, 31 female 14 male, whose ages range between 30 days to 16 years old were studied on a multislice CT scanner (Mx8000; Marconi Medical Systems) with slices of 2.5 mm thickness; 1.3 mm reconstruction interval; 90 kV; 15 mAs and 0.375 pitch. Patients had clinical suspicion of polyp lesions. Both supine and prone acquisition were carried out. A bowel cleansing preparation was necessary the day before. The images were post processed on a workstation (MxView; Marconi Medical Systems) using 2D, 3D and virtual colonoscopy reconstructions. When the VC was positive, a conventional colonoscopy (CC) was performed. Results: 22 VC studies were negative. In the 20 positive ones, VC detected 31 polyps and the CC only 27. Conclusion: VC can replace the barium enema as a first step in the diagnosis of polyp lesions. It is faster, less invasive, low radiation dose is needed and no complications has been seen. VC shows the exact location of the lesion and the distance from the anus so the colonoscopic resection is performed faster, reducing the time of the anesthesia needed.

• the diagnosis between active lesions and sequels, • the therapeutic management depending on the situation of the lesions compared to the levator ani muscle, • the additional value of MRI compared to EUS. Conclusion: MRI is the examination of choice for the exploration of perineal lesions in Crohn's disease, because deep pelvic involvements are frequent and difficult to assess at digital examination. MRI allows a precise analysis, which is complementary to EUS, especially for the lesions extending into the ischoanal fossae or the supralevator space. It appears even more useful for the management of the new medical treatment (antiTNF antibody).

Sensitivity of native tissue harmonic ultrasound compared to double contrast enteroclysis in different stages of ileocecal Crohn's disease H. Kárteszi, K. Kiss, Z. Tarján, E.K. Makó; Budapest/HU Purpose: To determine the sensitivity of deep penetration, high resolution ultrasound in different stages of ileocoecal Crohn's disease (CD) compared to enteroclysis and final diagnosis. Method: We have surveid the examinations of 54 patients (30 females, 24 males, ages of 18 -71) in whom CD have been verified either by further operation (8 cases) or by biopsy. The pathological changes in all cases were located to the ileoceacal region or to the neoterminal ileum. Morphologic signs of CD were searched for by enteroclysis (administration of 30 w/v% Ba-suspension and 5 % methylcellulose suspension with 100 -120 ml/min flow rate through a nasojejunal tube) and US examination (convex and linear transducers of 4 -8 MHz receiving frequency with Native Tissue Harmonic Imaging, Acuson Sequoia). Results: In early (superficial) stage (12 cases) no enteroclysis was negative (100 % sensitivity), but because of nonspecific changes in 6 cases the diagnosis was doubtful in early stage. 6 US examinations were positive (50 % sensitivity) and in transmural state both methods were 100 % sensitive. Six of 8 surgically verified fistulas had been diagnosed by enteroclysis, 3 by US and 2 by both methods. Three abscesses of 3 have been detected by US and 1 by enteroclysis before surgery. Conclusion: Sensitivity of Native Tissue Harmonic US is worse than that of enteroclysis in early stage which questions its use in new cases of suspected CD. For follow up in advanced cases US can replace enteroclysis. Sensitivity for detecting abscesses might compensate missed fistulas.

CT scan features of peritoneal carcinomatosis treated with intraperitoneal chemohyperthermia (IPCH) C. Dromain, A. Bisdorff, D. Elias, S. Antoun, M. Ducreux, R.C. Sigal; Villejuif/FR Purpose: Describe CT findings of peritoneal carcinomatosis, after complete surgery and treatment with intraperitoneal chemohyperthermia (IPCH) and differentiate post-treatment modifications from post-treatment complications. Materials and methods: Between 1996 and 2000, forty consecutive patients (22 women, 18 men, mean age 41 years), were treated by surgery and with IPCH, at the Institut Gustave Roussy for peritoneal carcinomatosis. 31 of these patients underwent helical enhanced CT scan of the abdomen and pelvis during the postoperative period (day 3 to day 15). CT-scans were reviewed retrospectively by two blinded observers. CT abnormalities were compared to the clinical and radiological evolution, to distinguish between post-treatment modifications and post-treatment complications. Results: Post-treatment CT scans were normal in 5 patients, showed post-treatment radiological modifications in 18 patients and post-treatment complications 8 patients. The post-treatment CT modifications included compartmentalized ascites in 13 patients, bowel thickening in 8 patients, peritoneal thickening in 12 patients, increased intraperitoneal fat density in 6 patients and peri-hepatic scalloping in 3 patients. Complications included intra-abdominal abscesses in 3 patients, bowel leakage in 2 patients, hemoperitoneum in 3 patients, pyelitis in 1 patient and pericarditis in 1 patient. Conclusion: Knowledge of early CT findings after IPCH treatment in peritoneal carcinomatosis makes it possible to differentiate post-treatment modifications from complications and to prescribe accurate treatment management.

Bowel wall thickening: Helical CT evaluation E. Kailidou, V.G. Katsiva, V. Bizimi, G. Michailides, A. Manataki, M. Tibishrani; Athens/GR Bowel wall thickening is a relatively subjective sign depending on an optimal CT study. A wide variety of pathologic entities, both intra and extra intestinal, can cause bowel wall thickening. The diagnosis of the underlying disease continues to pose a significant challenge. The main goals of this presentation are to describe and classify the varied appearance of bowel wall thickening and to present potential pitfalls in interpretation. From our archives, 140 helical abdominal CT studies were collected, where bowel wall thickening was present. CT studies were performed using the following protocols: unenhanced study, oral or/and rectal contrast administration, rectal air-in sufflation, intravenous contrast medium administration or combination of the above. We retrospectively evaluated the studies with emphasis on the following CT criteria: length of involvement (focal, segmental, diffusely distributed), degree of thickening (mild, marked), symmetry or asymmetry of thickening, bowel contour (smooth, irregular, lobulated), pattern of enhancement (homogeneous, heterogeneous, increased, decreased) and presence or not of associated findings (exophytic component, adjacent mesentery, lymphadenopathy, distal metastases). The imaging findings were correlated with confirmed final diagnosis in 128 patients.

In the presence of bowel wall thickening a solitary CT criteria was not specific. In the appropriate clinical context, combination of CT criteria provided an accurate diagnosis in some cases or limited the range of differential diagnosis in most cases. This presentation will illustrate the imaging findings in a wide spectrum of diseases and give valuable teaching points, which can help radiologist to render specific diagnosis.

MRI in staging advanced gastric cancer compared with CT A. Gligorievski, K. Gjoreski, D. Georgiev, A. Karagjozov; Skopje/MK Purpose: The purpose of our study was to evaluate the role of MRI with drug induced hypotonia and water filling in staging advanced gastric cancer (AGC) and to compare it with that of computed tomography (CT). Methods: We prospectively performed both MR and CT examinations on 17 patients with AGC proven by endoscopic biopsy. Contrast-enhanced CT and MRI with a 1.0 T scanner using T1 OUTFC, SPIR TSE and T2 UTSE sequences in COR, SAG and TRA plane, were obtained in each patient after injection of antiperistaltic drug and ingestion of 700 ml of tap water. CT and MR images were analyzed by two radiologists in consensus without any information from other images. Results: T and N staging of AGC was determined according to the TNM classification. All patients underwent surgery after both examinations. Diagnostic accuracy of each staging of AGC on CT or MRI was evaluated by comparison with the pathologic results. MRI was slightly superior to CT in T staging (81 vs. 73 %, respectively; p < 0.05). Although MRI had a tendency to overstage the pathologic T2 cancer, positive predictability of T2 stage and sensitivity of T3 stage were high (100 %, respectively). Regarding the N staging, CT was slightly superior to MRI (73 vs. 65 %; p > 0.05). However, both CT and MRI demonstrated the tendency of understaging in N staging. Conclusion: Although MRI was superior to CT in T staging, MRI cannot completely replace CT in staging AGC because of its limitation in N staging.

Detection of gastric pathology with CT gastroscopy N. Furukawa, H. Nishihara, K. Kimura, K. Higaki; Kurume/JP Purpose: To estimate the sensitivity and specificity of computed tomographic (CT) gastroscopy obtained by multislice helical CT in detection of gastric pathology. Materials and methods: 50 consecutive patients with gastric pathology including 37 (17 early and 20 advanced) gastric adenocarcinoma, 7 gastric SMT, 3 benign ulcer, and 3 lymphoma were reviewed. All patients underwent multislice helical CT (MSHCT) and conventional gastroscopy. Volume data obtained by MSHCT were transferred to a workstation to make CT gastroscopic images. CT gastroscopic images were evaluated separately by two radiologists blinded to the results from conventional gastroscopy and other imaging studies. Findings were compared with those of gastroscopy and pahology, which were the standard. Results: The sensitivity and specificity with CT gastroscopy were 47 % and 45.5 % in early gastric cancer, 100 % and 96.7 % in advanced gastric cancer, 100 % and 93 % in SMT, 66.7 % and 93.6 % in benign ulcer, and 66.7 % and 89 .4 % in lymphoma, respectively. It was difficult to detect flat type early gastric cancer and lesion less than 5 mm in diameter, and differentiate elevated type early cancer C A B D E F 366 Abdominal and Gastrointestinal from SMT, flat depressed type early gastric cancer from lymphoma or benign ulcer scar, and excavated type early gastric cancer from benign ulcer on CT gastroscopy. Conclusion: The sensitivity and specificity with CT gastroscopy in early gastric cancer was unfavorable. However CT gastroscopy seems to have acceptable diagnostic ability among other gastric pathology and could be performed simultaneously to evaluate other organs. We should perform this imaging technique with knowledge of its limit

Gastrointestinal tumors of stromal origin: How far can we go with imaging modalities? S. Castillo, A. Vilaplana, B. Vargas; Seville/ES Purpose: To evaluate the efficacy of imaging techniques in defining localization and appearance of gastrointestinal stromal tumors, and in determining radiographic malignant features. Methods and materials: We reviewed the records of 15 patients (8 men, 7 women, mean age 56) with histologically proven gastrointestinal leiomyosarcomas (n = 7), plexosarcomas (n = 3) and leiomyomas (n = 3). Ultrasonography was performed in 3 patients, CT in 8, barium studies in 7 and angiography in 3. Results: Due to their nonspecific clinical presentation, imaging protocols have not yet been established. In those pathologycally proven leiomyosarcomas or plexosarcomas, CT revealed a large lobulated mass with necrosis, and infiltration of the mesenteric fat. Tumors with benign appearance were smaller, homogeneus and had smooth contours. Neither malignant nor benign tumors had regional lymphadenopathy nor metastasis at diagnosis. Barium studies were useful in detecting origin and malignancy (large intramural exophytic mass with ulceration), but not extension nor size. Ultrasonography depicted an abdominal mass with large exophytic component and peripheral necrosis (highly suggestive of stromal tumor), although origin could not be determined. Angiography helped detecting tumor origin but did not allow confident diagnosis of stromal tumor. Conclusion: It is important to be aware of the radiologic features of gastrointestinal stromal tumors, as they are often amenable to surgical resection. Radiologic malignant features may determine prognosis more accurately than histopathologic criteria. We consider that the most confident diagnosis regarding origin, size, morphology, necrosis, local extension and distant metastasis were given by CT studies.

Oesophageal stent implantation: Role of radiological examination T. Schiszler, Z. Tarján, K. Kiss, Z. Vighváry, Á. Balázs, E.K. Makó; Budapest/HU Purpose: The poster is demonstrating the role of conventional radiological (swallowing) examination in indicating and managing fluoroscopy guided oesophageal stent implantation done by radiologist in cooperation with surgeons. Method: During the last 21 years 634 implantations were done in patients with malignant oesophageal stenosis. After visualizing the place of the stenosis by swallowing iodinated contrast material oesophageal dilation was performed, followed by stent implantation. Out of 634 patients with malignant stenosis 143 had oesophago-bronchial/tracheal fistulas. In 18 cases, implantation was tried despite tumour localisation difficulties (cardial tumours). Results: 89 % (544 patients) showed an improved life quality (decreased dysphagial severity) after implantation. Stent displacement occurred in 52 patients, in 16 cases re-stent implantation was needed. In 22 cases, implantation could not be carried out due to technical reasons. In three cases, perforation was found after dilation and seven patients presented bleeding of the carotid artery. Stent implantation was always indicated if fistulas were present or in case of severe dysphagia. The contraindications were mostly technical and positional problems: in case when the stenosis was localized close either to the cardia or the origin of the oesophagus endoprothesis could not be used. Conclusion: Most cases swallowing examination is the only needed examination in indicating or contraindicating oesophageal stent implantation. The radiologist visualizes the position and length of stenosis, the presence or absence of fistulas; and plays a big role in guiding the implantation. The poster summarizes the indications and contradictions.

Virtual oesophagoscopy. A new alternative in diagnostic algorithm? Preliminary experience P.M. Carrascosa sr. 1 , G. Sangster 1 , G. Sali 1 , J. Chiocca sr. 1 , C.M. Capuñay jr. 1 , Casella sr. 1 , S. Chandra 2 , D. Matthews 2 , J.M. Carrascosa sr. 1 ; 1 Buenos Aires/AR, 2 Cleveland, OH/US Purpose: To define the role of virtual oesophagoscopy (VE) in the diagnosis of stenotic lesions in comparison with conventional endoscopy (CE). Materials and methods: Twelve patients with known or suspected congenital or acquired oesophageal stenosis were evaluated with VE and CE. VEs were carried out with a multislice CT scanner (Mx8000; Marconi Medical Systems), using 2.5 mm slice thickness and 1.3 mm reconstruction intervals. Two adquisitions were performed in 10 -15 seconds, being the first one previously distended with effervescent agent and the second one with barium contrast. Patients with oesophageal atresias, the distal and proximal ends had to be distended through mouth and through the gastrostomy. Images were sent to a workstation and reprocessed in three different ways: (1) Bidimensionally, (2) Tridimensionally, (3) Virtual Endoscopy. Findings of the two methods were compared. Results: 83 % of the patients showed stenotic lesions: (a) congenital n = 3, (b) acquired n = 7. The acquired causes revealed benign etiology (43 %) and malignant etiology (57 %). VE was useful in all the patients. It determined the length of the lesions, thickness of the wall as well as indirect signs (lost of fat planes), showed whether the lesion was benign or malignant. The two remaining patients revealed wall ulcerations and hiatal hernia. In patients with oesophageal atresias, the distance between the ends were the same as the ones revealed by conventional methods. Conclusion: VE is a new non-invasive method useful in the evaluation of the stenotic lesions. The combined examination (bidimensional-tridimensional) allows physicians to diagnose the illness and to difference stages.

MR imaging of the normal mesentery using true FISP, HASTE and postgadolinium fat-suppressed FLASH images A. Athanassiou, M. Daskalogiannaki, N. Papanikolaou, T.G. Maris, P.K. Prassopoulos, N. Gourtsoyiannis; Iraklion/GR Purpose: To examine the feasibility of different MR sequences in the demonstration of the normal small bowel mesentery. Material and methods: The study comprised 11 small bowel examinations (SBE) without abnormalities, selected from a series of 48 consecutive SBE. Patients were examined in the prone position using axial and coronal true FISP, HASTE and fat-suppressed, post-gadolinium 3D FLASH sequences. Demonstration of mesenteric vessels (central, segmental, vasa recta), homogeneity of mesenteric fat, contrast resolution between mesentery-adjacent organs, depiction of normal small lymph nodes and artifacts presence were separately analysed for each sequence on a 5-point grading scale. Results: True FISP images provided best results on anatomic demonstration of mesenteric vessels, fat and small lymph nodes. Ranking of HASTE images were significantly lower (p < 0.05) for all parameters evaluated, due to blurring effects on small anatomic structures. 3D FLASH were inferior (p < 0.05) to true FISP sequences only on the depiction of vasa recta and small nodes. Conclusion: MRI is an excellent modality for a detailed anatomic demonstration of the mesentery. True FISP and fat-suppressed post gadolinium 3D FLASH sequences may be included in an intergraded protocol for imaging the mesenteries.

Spigelian hernia: Usefulness of ultrasonography M. Grande Barez, A. Perez Vigara, P. Villar Castaño, J. Benito Diaz, M. Jimenez De La Peña; Madrid/ES Purpose: Spigelian hernia is a rare hernia of anterior abdominal wall, usually acquired. Due to low incidence and frequent atypical presentations diagnosis use to be difficult. The purpose of this study was to demonstrate the role of sonography in the initial diagnosis of spigelian hernias. Materials and methods: We report our experience in 4 cases in which US permitted a correct diagnosis of surgically confirmed Spigelian hernias. 3 patients had complained of localized abdominal pain in linea semilunaris. 2 patients had obstruction symptoms. Results: Conventional radiographic examinations are of limited value in recognising these hernias specially when the hernial sac does not contain bowel. At present, CT is the best imaging method in diagnosis. However, US allow the identification of the hernial sac and the contents of the hernia in different positions and during the Valsalva maneuver. 

Conclusion: Spigelian hernias can be difficult to diagnose clinically. In this study US with real-time capability, portability and low cost was been shown to be an effective and helpful method in the diagnosis of these uncommon hernias.

Multislice spiral CT in appendicular mucocele diagnosis V. Panebianco, A. Laghi, C. Catalano, M. Assenza, I. Clementi, R. Ferrari, F. Iafrate, R. Passariello; Rome/IT Aim of our study is to evaluate diagnostic impact of multislice spiral CT with appendicular mucocele. Introduction: Multidetector spiral CT provides an high spatial resolution in a short examination time. Mucocele is a rare lesion that is revealed only on 0.2 -0.3 % of the all surgery for appendicectomy. Aspecificity of its symptoms and relatively frequency of complications such as rupture, malignant transformation, obstruction caused by intussusception requires a precise and fast diagnosis. Material/methods: 6 patients with appendix mucocele were referred to the our department to underwent non-enhanced multislice CT. All patients were previously evaluated by US. Images were obtained with a Multidetector Spiral CT Volume Zoom with 2 mm thickness, 160 mAs, 120 kV, 2.5 mm reconstruction increment. Coronal and sagittal 2D reconstruction were performed in real time so to evaluate the involvement of other abdominal structures. In two cases there was a diagnostic doubt with iliac aneurysm, in one case with caecal diverticulum, in three case with ovaric tumefaction. Results: The lesion was well evaluated in 100 % of cases. Densitometry characteristics of dense-fluid tissue with calcified walls and the continuity with the caecal lumen, revealed by coronal reconstruction allows the final diagnosis. A clear cleavage plane with the iliac vessels can be observed in all patients so to permit differential diagnose with i aneurysm. All cases were confirmed by surgery. Discussion: Multislice spiral CT is valid method in diagnose of appendix mucocele, due to high resolution and low thickness acquisition (1 to 2 mm).

Ultrasound findings of colonic diverticulitis J. Benito Diaz, P. Villar Castaño, C. Muyor Piñero, M. Grande Barez, P. Manjon Luengo; Madrid/ES Purpose: To assess the value of sonography as the initial imaging procedure in patients suspected of having acute diverticulitis of the colon, we evaluate the ultrasound findings of diverticulitis, diverticulosis and normal colon. Materials and methods: We performed 54 graded compression sonography with 3.5 and 7 MHz sector or convex linear transducers. 35 of them were made after contrast enema. 17 with clinical symptoms and signs of acute diverticulitis 1 after CT; and 1 surgical specimen. We evaluated mural thickness, muscular layer thickness (hypoechoic), inflamatory changes of pericolonic fat, inflamed diverticula sign, intramural or pericolic collection and fistulous tracts. Results: In all patients with normal colon or diverticulosis the mural thickness was normal or less than 5 mm. The hypoechoic layer was less than 2 mm. No-one showed inflamed diverticula sign and no other diverticulitis signs. However, patients with acute diverticulitis, the mural thickness was from 5.5 to 15 mm and the muscular layer thickness from 2 to 10 mm. All of them showed inflamed peridiverticular fat. Some cases presented other signs (inflamed diverticula, pericolonic abscess, fistulous tracts). Conclusion: The US signs of acute diverticulitis were: mural thickening, inflamed diverticula sign, inflamed pericolic fat, intramural or pericolic abscess and sinus tract or fistulous tract. Although sonography is not expected to replace CT in the evaluation of diverticulitis, it should be used as initial imaging procedure. Results: 31 patients (51.5 %) had ulcerated lesions, 8 (13.2 %) showed cathartic colon, 6 (10 %) candidiasis; in 5 (8 %) cases diagnosis was pseudomembranous colitis, 4 patients (6 %) presented hypoperistalsis, 3 (5 %) had GI bleeding or hematoma, 2 (3.3 %) developed an ischemic or thrombotic disease and the one remaining (3 %) colonic urticaria. Conclusion: Radiology proved to be useful in the diagnosis and orientation of a therapeutic decision in patients with drug-induced gastrointestinal lesions. Purpose: Suspicious breast lesions usually present as hypoechoic nodules on ultrasound. However, exceptionally breast cancers may be hyperechoic. Our purpose is to show our experience with hyperechoic lesions of the breast (HLB). Material and methods: Since May 2000 until present we have reviewed 1268 breast ultrasound scans, finding 9 cases of HLB. Clinical, mammographic, ultrasonographic and pathologic findings were studied. Results: All lesions were clinically palpable. In two cases the clinical evaluation was consistent with mastitis, and in two cases with inflammatory carcinoma. Mammograms were available in 6 patients, showing the lesions as asymmetrical densities (5 cases). In one case, mammography showed no findings. Ultrasound findings were poorly delineated nodules (4 cases) and complex lesions (5). Biopsy was performed in 6 cases: 1 fat necrosis, 3 infiltrating ductal carcinomas, 1 infiltrating lobular carcinoma and 1 micropapillary ductal carcinoma. Conclusions: In our experience, hyperechoic lesions were palpable in all cases, appeared predominantly as asymmetrical densities on mammograms and were malignant in a high proportion of cases. The radiologist should be aware of these lesions that may be easily confused with normal breast tissue.

Power Doppler imaging of palpable breast enlargement in men S. Tukel, H. Ozcan; Ankara/TR Purpose: To determine contribution of Power Doppler imaging to non invasive differential diagnosis of palpable breast enlargement in men. Methods and materials: 50 male patients with a complaint of enlargement of one or both breasts were examined by mammography, ultrasound and power Doppler, consecutively. Presence and type of true gynecomastia, definable mass lesion with or without microcalcifications and pathologic vascularity within the breast parenchyma were determined. Fine needle aspiration biopsy was employed for all mass lesions but lipoma. Results: Age of the patients varied between 11 and 84 with a mean of 45.6. In 3 of the 50 patients (6 %) enlargement was caused by malignancy, 1 (0.5 %) by unilateral lipoma, and the rest (92 %) by true gynecomastia of one or both breasts. Mammography was a sensitive method for detection of malignancy (100 %), demonstrating pleomorphic microcalcifications in all lesions. Power Doppler was also sensitive (100 %), since pathological vascular pattern was detected in all cases with malignant histology. Ultrasonography helped differentiate nodular gynecomastia and mass lesions from diffuse glandular hypertrophy. Conclusion: Power doppler was found to be highly sensitive method for malignancy in the evaluation of breast enlargement in men. Since negative pathologic vascularity can support gynecomastia versus malignancy, power Doppler may be used as an adjunct to mammographic and sonographic findings.

US-evaluation of the changes in malignant breast lesions after preoperative radiotherapy H.P. Shevchenko; Moscow/RU Purpose: To evaluate US-changes of the malignant breast lesions after preoperative radiotherapy. Materials and methods: 105 female patients (age range 33 -87 years, mean age 56.32 ± 7.5) with 107 breast cancer (T1N0 -T3N2) were examined on HDI-5000 ATL-Philips using B-mode, 3D-PD before and after preoperative radiotherapy (summary dose 20 -44 Gr). Mean tumour diameter was 2.36 ± 0.4 cm. Results were assessed using HDI-Lab. Results: After radiotherapy lesions' diameter decreased by 0.1 -3.0 cm in 79.4 %, increased by 0.03 -0.4 cm in 13.1 %, didn't change in 7.9 %. The dorsal tumours' echogenicity raised in 43.9 %, didn't change in 53.3 %, decreased in 2.8 %. Using HDI-Lab peripheral tumour echogenicity raised from 3.83 to 4.68 dB in 97, 8/86, 9 %(20/44 Gr) . Peripheral vascularity decreased in 34.2 %(20 Gr), in 54.3 %(44 Gr). Vmax, Vmin, RI increased after 20 Gr in all tumour vessels and decreased after 44 Gr in peripheral vessels. Conclusion: US permits to evaluate changes of the malignant breast lesions after radiotherapy and to assess the treatment efficacy.

3D power Doppler (3DPD) vascularisation of breast nodules: A long period experience C. Caiazzo 1 , L. Assentato 1 , F. Girolami 1 , G. Calvino 1 , G. Pagano 1 , R. Vivenzio 1 , A. Salzano 2 , A. Nunziata 1 ; 1 Naples/IT, 2 Frattamaggiore/IT Objective: Confirmation and validation of 3DPD evaluation of solid breast nodules. Material & methods: 69 solid breast nodules, cytologically proved, were retrospective evaluated in B-mode, CD and PD and divided in 3 types regarding their vascularization: absence, peri-nodular and intranodular. We performed 3DPD reconstruction and an expert operator blindly evaluated the mode of vascularisation. Results: The second operator found the same types of vascularisation (100 %) but better visualisation of the intra-nodular vessels. Conclusion: 3DPD in this study with larger group of patients (compared to a previous study with less number of patients) seems to show the same accuracy but it improves visualisation of intra-nodular vessels, and could help surgical planing.

Breast intraductal masses: US-guided localization after galactography M. Calabrese, A. Iozzelli, A. Imperiale, A. Beghello, C. Conti, V. Ciangherotti; Genova/IT Purpose: To demonstrate the possibility of US-guided localization of intraductal masses after galactography. Method and materials: 20 patients (aged 25 -60 a) with hemorrhagic and/or serohemorrhagic nipple discharge underwent galactography, which demonstrated: 15 single filling defects (4 of the located in the peripheral ductal branches), 4 obstructions of the main duct (3 of them associated with a nodular lesion), and multiple filling defects in 1 patient. All patient underwent ultrasonography, which demonstrated: 16 intraductal masses, 2 endocystic lesions, and 2 hypoechoic nodules. US-guided localization was performed (10 MHz small parts probe; AU530, ESAOTE, Genova, Italy) in all cases using a charcoal solution. For all lesions histopathological evaluation was done after surgery. Results: At histopathological evaluation, all the lesions were included in the specimen. Histopathology revealed 1 papillary carcinoma and 19 papillomas. Conclusion: A pre-surgical US-guided localization is useful for the surgeon, and allows easy and careful excision. Failure to remove the intraductal lesions at surgery is a possibility to be taken into account, in particular for peripheral lesions.

Investigation of breast cancers with atypical ultrasound images M. Mizutani, H. Iwata, T. Iwase, S. Miura; Nagoya/JP Purpose: The majority of breast cancers are visible as a mass when imaged with ultrasound (US). Occasionally, we have seen breast cancers with atypical ultrasound images surrounded by thick hyper echoic structures and posterior echo attenuation, and the diagnosis of these cancers is difficult. We investigated these cases. Materials and methods: 608 breast cancers diagnosed at the Department of Breast Surgery, Aichi Cancer Center between January 1999 and December 2000, were included in this study. US examinations were performed with a high frequency wideband transducer (GE LOGIQ700MR, M12L probe) and mechanical sector transducer (Aloka SSD2000). The clinical reports of all patients were reviewed. Only 3 cases were breast cancers of ultrasonographically non-mass forming types. In these 3 cases, we compared the findings of physical examination, mammography, MRI, and pathology. And then we analysed US findings on basis of pathology and ultrasonic tissue had exhibited atypical US images surrounded by thick hyper echoic structures and posterior echo attenuation. With physical examination, mammography and MRI, 3 cases were recognized as localized malignant masses. Histopathologically, all cases were invasive ductal cancers with extensive fat infiltration. Because of extensive fat infiltration, unexpected ultrasonic images were formed which disturbed the mass image formation. Conclusion: Extensive fat infiltration of invasive ductal cancer ultrasonographically forms thick hyperechoic structure and posterior echo attenuation. Although breast cancers of ultrasonographically non-tumour forming types are rare, in order to prevent misdiagnosis of these breast cancers, we must understand how unusual ultrasonic images are formed. To determine the role of contrast-enhanced power Doppler sonography (CEPD) following mammography and grey scale sonography combination (MG + GSS) and power Doppler (PD), in the differential diagnosis of breast lesions. Material and method: PD was applied to 69 breast lesions (size 7 -44 mm, mean 16.48), in 68 patients before and after intravenous bolus injection of Levovist® (4 g, 300 mg/ml, Schering, Germany), following MG + GSS evaluation. On MG + GSS, 16 lesions were diagnosed as "probably benign", 32 as "probably malignant" and 21 as "indeterminate". Subjective criteria were used in the evaluation of PD findings, before and after Levovist® administration: (1) Presence and estimated area of vascularity within the lesion.

(2) Amount of enhancement following Levovist® injection. Marginal inhomogeneity test was used to determine the significance of contrast enhancement in benign and malignant lesions. Sensitivity and specificity of the modalities were compared to determine the role of CEPD as an adjunct to MG + GSS in the differential diagnosis of breast lesions. Results: Of the 69 lesions, 28 were malignant and 41 were benign. Sensitivity and specificity of MG + GSS were found 100 % and 39 % respectively. 3 malignant lesions (11 %) which were negative with PD revealed significant vascularity with CEPD. 8 lesions (20 %) which were correctly diagnosed as benign on PD received false-positive diagnosis on CEPD. Sensitivity and specificity of (MG + GSS) + PD was 82 % and 56 % and of (MG + GSS) was 86 % and 68 %, respectively. Both for benign and malignant lesions, amount of enhancement following Levovist® injection was found to be significant (p < 0.05). Conclusion: CEPD may be useful to improve the specificity of MG + GSS.

Characterisation of breast carcinoma using power Doppler imaging, in correlation with lymph node status V. Beslagic, O. Duric, F. Dalagija; Sarajevo/BA Purpose: To assess correlation of breast cancer vascularity, as revealed by power Doppler with lymph node involvement. Material and methods: We surveyed 87 patients who were suspected for breast carcinoma. All patients who underwent power Doppler sonography of solid masses had histology proven carcinoma. Power Doppler findings were categorised according to type of angioarchitecture: lesion with penetrative vessels, peripheral vessels, and without perfusion. These finding were correlated to node status. Lymph node involvement was confirmed by pathologic finding. Results: Of 87 patients with breast carcinoma, lesions with penetrative vessels were seen in 27 (31 %) patients and those with peripheral vessels in 35 (40 %) patients. Vessels were not found in 25 (29 %) patients. Vessels lymph node involvement was seen in all patients (27 -100 %) with penetrative lesion. Of 35 patients with peripheral lesion vessel lymph node dissection was done in 31 (89 %) patients. In patients with no visible lesion vessel lymph nodes were found in 2 (8 %). Conclusion: Power Doppler is valuable diagnostic method in tumour vascularity characterisation. Presence of tumour vessels revealed by Power Doppler is strongly connected with lymph node involvement. In breast carcinoma without visible vessel in power Doppler mode lymph node involvement is unlikely to be found. Purpose: To evaluate 100 stereotactic biopsies of mammographically detected non palpable breast lesions using the advanced breast biopsy instrumentation (ABBI) technique. Material and methods: Between September 1998 and April 2000, 100 women underwent breast biopsies with ABBI system using surgical 10 to 20 mm cannulas, and a dedicated stereotactic device. All procedures were carried out under local anaesthesia in an outpatient setting. Indications were reassessed according to BI-RADS classification of ACR (masses n = 33, microcalcifications n = 67). Specimen radiographs and post-procedure mammographies were performed to confirm the quality of excisional breast biopsy. Results: Of the 100 biopsies, histologic diagnosis was benign in 62 and malignant in 38. 28 of 38 malignancies had positive margins and these patients underwent surgery. In the 10 cases of negative margins, women did not undergo surgery but radiotherapy only due to a very old age, an contraindication of anaesthesia, or refusing surgery. Conclusion: ABBI technique avoided surgery with general anaesthesia for 67 women (62 %) with benign lesions. In malignant lesions this technique did not have any therapeutic indication except in occasional cases.

Minimally invasive breast biopsy (MIBB): Analysis of 100 cases A. Demir, M.-H. Dilhuydy, B. Barreau, C. Henriquès, F. Valentin, R. Gilles, I. Audigey, N. Ranchon, G. MacGrogan, V. Picot; Bordeaux/FR Purpose: To evaluate 100 stereotactic 8 gauge biopsies of mammographically detected lesions for diagnosis or before treatment using the minimally invasive breast biopsy (MIBB) technique. Material and methods: Between September 1998 and April 2000, 100 women underwent breast biopsies using MIBB system with a dedicated stereotactic device. All procedures were carried out under local anaesthesia in an outpatient setting. Indications were reassessed according to BI-RADS classification of ACR (microcalcifications n = 94, masses n = 6). Specimen radiographs and post-procedure mammographies were performed to confirm the quality of procedure. Results: In a diagnosis goal (ACR3 or ACR4 abnormalities): of the 49 biopsies, histologic diagnosis was benign in 44, malignant in 4. In one case, presence of atypical hyperplasia led to surgery. Before treatment (ACR5 abnormalities): of the 51 biopsies, 38 were malignant, 4 underestimated malignant lesions, 1 malignant lesion was missed and 8 were benign in contradiction with mammographic appearance. Conclusion: In a diagnosis goal MIBB avoided surgery for 37 women (84 %) with benign lesions. Before treatment MIBB allowed one-step surgery for 37 women (86 %) with malignant lesions. Results: In 50 out of 73 cases the MR-VB was not performed due to absent enhancement and inappropriate scheduling (day 7 -17 of menstrual cycle, withdrawal of hormonal replacement therapy). 6 cases were not associated to MR-VB (2 MRfailures, 2 patient refusals, 2 patient motion), 3 were partly associated (patient too large). 14/73 drop-outs (3.5 % of scheduled VBs) concerned limitations of MR-VB (7 limited access, 5 breast too thin, 2 too strong compression leading to repeat MR-VB or MR-localisation). Among 333 VBs 10 major problems occurred leading to uncertain biopsy results (1 MR failure, 4 operator failures, 3 strong patients A B D E F 370 Breast motion, 1 technical problem), 2 lesions escaped the probe. Altogether 1 % failures were associated to MR-VB and 2 % not associated. All failures/problems were recognized on post-biopsy imaging. Conclusion: MR-VB is very accurate. Failures can be recognized on post-biopsy imaging. In case of problems MR-VB can be converted into on MR-guided localisation procedure.

Diagnostic yield in breast core-biopsy is dependent on the method used in guiding R. Salvador, M. Salvador, O. Domínguez, A. Durán, V. Pineda, C. Lafay; Barcelona/ES Purpose: Large needle breast core-biopsy is actually considered the gold standard in the diagnosis of non-palpable lesions. The method used to guide the needle can influence its diagnostic yield. This study aims to evaluate the predictive value of the results depending on the method used in guiding the large needle breast core biopsies. Methods and materials: We have retrospectively reviewed the results of 2807 consecutive breast core-biopsies performed between 1992 and 2001 in three different facilities. 2214 with stereotactic analogue device, 294 under ultrasonographic guidance and 299 under digital stereotactic equipment. We compare the results of core biopsy samples to the surgical results when they were available. We evaluate the concordance between them and the upgrade on the diagnosis in the three different groups. Results: Among the patients whose surgical results could be recorded, of 1074 analogue stereotactically guided samples, 173 were upgraded after surgical intervention. Only 9 in 127 ultrasound guided biopsy results, and 6 in 99 guided with digital stereotactic equipment were upgraded. Conclusion: Digital stereotactic guidance has a better negative predictive value when compared to analogical equipments improving its value from 16 % to 6 %, while its value is similar to that obtained with ultrasound (7 %). Only digital stereotaxia and ultrasound should be used when indicated, while analogue equipments should no longer to be used in guiding interventional procedures because of its poor yield.

Stereotactic 14 G core needle breast biopsy: How many shots do we need to detect malignancy Purpose: To find out how many passes with a stereotactic core needle biopsy (SCNB) device should be performed to detect malignancy in a nonpalpable breast lesion. Methods and materials: An automated, 14 gauge SCNB device was used to obtain multiple breast samples from 99 consecutive patiens (mean age 57 a, range 36 -80 a) with 104 mammographically detected breast lesions (51 solid, 53 with microcalcifications (MC), mean size 10.3 mm). The first sample was collected into container A, the second and the third into container B, and all the additional samples into container C. The mean number of passes was 7 per lesion (range 4 -15). An experienced pathologist analyzed each container separately for the presence of malignancy. All non-excised lesions were followed up with mammography (mean 21 months, range 10 -34 months). Results: For final diagnosis, 48 lesions proved to be malignant in subsequent surgical excision, whereas 56 benign lesions were stable on mammographic follow-up. For all lesions, sensitivity of multiple samples was 100 %. The result of the first sample was false negative significantly more often in MC lesions (n = 9, including one atypical ductal hyperplasia) than in solid lesions (n = 2, p = 0.03). Combined results of containers A and B yielded a sensitivity of 95 % for solid and 100 % for MC lesions. Conclusion: Three passes obtained with a 14 gauge SCNB device are sufficient to detect malignancy in a mammographically suspicious breast lesion. In a lesion with MC, a single specimen may lead to a false negative diagnosis.

Psychological perception of stereotatic breast biopsy instrumentation procedures: 53 cases of stereotactic vacuum-assisted breast biopsy and 46 cases of advanced breast biopsy instrumentation B. Barreau, S. Tastet 

A form concerning psychological appraisal has been send to 167 women who underwent minimally invasive breast biopsy (MIBB) or advanced breast biopsy instrumentation (ABBI) procedure. Of these patients, 99 replied (53 MIBB and 46 ABBI). This form has been validated through statistical tolls which led to four significant factors: type of procedure, quality of life, informed consent and the personal perception after the procedure. Statistical analysis consisted on Chi-square test. Results: Statistically significant differences were found between MIBB and ABBI procedures. For the MIBB technique, women were more impressed by the room (p = 0.027), the noise (p = 0.038) and the procedure was considered more painful (p = 0.005). For the ABBI technique, the scar was considered more visible (p = 0.0017). Patients with malignant results had sleep perturbation (p = 0.019) and are more impressed by the technique which they found more uncomfortable (p = 0.0029). Conclusion: Both procedures were well tolerated. However, medical care, information before the procedure and histological results play a role in the patient's perception.

Papillary lesions of the breast (PBL): Accuracy of mammography and US and role of core biopsy with 14 G needles. Comparison with definitive histology I. Berra, G.E. Francescutti, I. Zunnui, V. Londero, M. Bazzocchi; Udine/IT Purpose: To evaluate the presence of suggestive mammographic and US findings of PLB and to show accuracy of large-core-biopsy (LCB) in evaluating these lesions. Materials and methods: A retrospective review of LCB in 1163 consecutive lesions revealed 37 PLB cases, with surgical correlation. Evaluating mammographic and US appearance lesions were classified as probably benign or malignant. K-test was applied to correlate mammographic and US diagnosis with definitive histology.

Results: LCB histological findings demonstrated 28 (76 %) benign, 5 (13 %) atypical, and 4 (11 %) malignant lesions. Histological findings after surgery confirmed benign and malignant lesions; among atypical lesions, 1 was benign and 4 were malignant (concordance of 86.5 %). Mammographic appearance of benign PLB was usually well-defined (71 %), oval (53 %) masses; papillary carcinoma was well-defined (50 %) or ill-defined, oval (50 %) or lobulated (50 %) masses, but never spiculated. US in benign PLB showed well-defined (84 %), oval (84 %), complex solid/cystic (52 %) mass with frequently posterior enhancement (60 %); papillary carcinoma showed well defined (50 %) or ill-defined (50 %), oval (50 %) or lobulated (50 %) mass, most commonly solid-inhomogeneous-hypoechoic mass. Statistical significance was reached between mammographic appearance and definitive histology (K = 0.333) while it wasn't present between US appearance and definitive histology (K = 0.199). Conclusion: US proved to be the best examination for identification of the solid component of these lesions; mammographic findings were better than US in differentiating between benign and malignant PLB. Percutaneous biopsy is required and it has shown to be reliable in diagnosis of benign and malignant PLB: surgical examination is required when atypical lesions are present. 

Evaluation of contrast enhanced 3D-images in breast cancer -comparison between 3D-CT and 3D-MR images in the same patients K. Hiraishi, K. Awai, T. Ueda, K. Yoshinari, A. Imai, F. Isohashi, S. Hori; Izumisano/JP Purpose: Many investigators have been reported about the efficiency of 3D images in breast cancer. However, there were no reports on the comparison between 3D-CT and 3D-MR images in the same patients. We performed both examinations in the same patients, compared the 3D images and will discuss the clinical value of these preoperative examinations. Material and methods: A total number of 34 patients had both contrast enhanced 3D-CT and 3D-MRI before surgery. 3D-CT was performed by multidetector row system of GE Light speed QX/i. 3D-MR was performed by Toshiba VISART hyper 1.5 T with fat suppression. Both 3D images and the pathological specimens were compared. Results: Spatial resolution was better in 3D-CT and it was easier to recognize the relationship between the lesion and the surrounding tissues. Metastasis to axillary lymph nodes could be visualized on 3D-CT. It was difficult to make orientation of real tumour depth from the skin on 3D-MR because there was less information about the surface. 3D-MR had the advantage in showing more information on feeding arteries or drainage vein. Mastopathic change and the tumour surrounding tissue were additionally enhanced more occasionally on 3D-MRI. Conclusion: There was a problem of radiation exposure and so 3D-CT should be used only for the cancer patients. 3D-CT was superior to 3D-MR regarding spatial resolution and diagnosing co-existing mastopathic changes. 3D-MR could show more information on feeding arteries or drainage vein. We should choose the more suitable examination for each case.

Role of magnetic resonance in the inflammatory carcinoma of the breast P. Belli, M. Costantini, M. Romani, C. Locastro, D. Terribile, G. Pastore; Rome/IT Purpose: To access the role of magnetic resonance imaging in the inflammatory carcinoma of the breast Methods and materials: 15 female patients with a clinical diffuse inflammatory process in the breast underwent mammography, sonography and magnetic resonance imaging. Dynamic contrast enhanced MR-mammography using T1-weighted sequences (SPGR) were acquired in coronal orientation. Presence/absence of contrast enhancement, morphology of enhancement and dynamic curve were evaluated. Results: Histological confirmation showed 10 cases of inflammatory carcinoma and 5 cases of mastitis (3 of these showed abscesses). Presence of enhancement was observed in all of patients. All of inflammatory carcinoma have a patch enhancement pattern and 7/10 of these have been one or more areas of focal enhancement. A patch enhancement was observed in 2 cases of mastitis while in the other 3 cases nodular focal areas with peripheral enhancement were seen. The dynamic curves were always wash-out type. Maximum signal intensity value was 70 % in 3/5 cases of mastitis and in 9/10 cases of inflammatory carcinoma. Patients with mastitis were followed up and in all cases a decrease of enhancement was seen. Conclusions: Our results suggest that magnetic resonance imaging in the characterization of inflammatory process of the breast is often non-specific; its role may be useful in the follow up of mastitis. The presence of focal areas of enhancement may be useful to differential diagnosis.

Image quality of CR-mammography by means of NEQ(u) and visual evaluation: Comparison with screen-film system M. Imanishi, F. Akazawa, H. Ikeda; Fukuoka/JP Objective: To evaluate and compare the image quality of mammography with computed radiography (CR) system and conventional screen-film system. Materials and methods: The image quality was evaluated by physically measuring NEQ(u) and visually using a phantom for the ACR (American College of Radiology)accreditation program. CR images were obtained with the FCR 9000 (Fuji), and high-resolution type Imaging Plate (HR-V). Screen-film images were obtained with Min-R 2000 screen and Min-R 2000 film (Kodak).

Regarding physical evaluation, NEQ(u) of screen-film image showed significantly higher value than that of CR image. However, regarding visual evaluation, both results were equivalent. CR systems were used to exclusively grade the type and frequency of mammographic processing in case of carrying out visual evaluation, but was not used these in case of physical evaluation. Conclusion: In conclusion, CR systems were inferior to Screen-film systems in physical evaluation. However, image quality of CR-mammography with image processing is clinically equal to that of screen-film systems.

Breast metastasis of alveolar rhabdomyosarcoma: Atypical magnetic resonance imaging findings S. Tukel, B.E. Dogan, H. Ozcan; Ankara/TR Objective: Define and demonstrate magnetic resonance imaging (MRI) findings of breast metastasis of an alveolar rhabdomyosarcoma of extremity. Methods and materials: 12 year-old girl with alveolar rhabdomyosarcoma in the soleus muscle of the right calf presented with a soft tissue mass on the upper outer quadrant of the right breast. Mammography, ultrasonography, colour Doppler imaging was performed. Subsequent magnetic resonance imaging consisted of non-enhanced and enhanced T1 weighted, fat suppressed, T2 weighted axial and sagittal, and coronal short-tau inversion recovery images. Results: A round, well-defined solid mass lesion was revealed on mammograms and sonograms. Colour Doppler imaging was enlightening, since arterial flow with high maximum velocity was the dominant finding. The mass was hypointense on T1 weighted images, markedly hyperintense with hypointense internal septae-like structures on T2 weighted images. Upon contrast administration, septae like structures showed moderate contrast uptake while rest of the mass remained unenhanced. Ultimate diagnosis was achieved by histopathologic examination. Conclusion: Primary alveolar rhabdomyosarcoma tumor may be undetectable and the patient may present with breast findings. Colour Doppler imaging might indicate a metastatic lesion in cases when MRI findings are inconclusive

Automatic elastic motion correction of subtraction images in MRmammography S.O.R. Pfleiderer 1 , J.R. Reichenbach 1 , H. Fischer 2 , W.A. Kaiser 1 ; 1 Jena/DE, 2 Freiburg/DE Purpose: Motion artefacts make it difficult to evaluate subtraction images of dynamic MR-mammography data sets for contrast enhancement kinetics. The aim of the study was to investigate whether motion artefacts are reduced after applying an automatic elastic motion correction and whether diagnostic findings disappear or pseudo lesions do occur on the subtraction images. Materials and methods: Automatic elastic motion correction was performed on 10 dynamic MR mammography data sets with severe motion artefacts seen on the original subtraction images. The original and corrected subtraction images of the first and the seventh minute after contrast media application were visually compared and ranked (better, similar, worse) with respect to image quality, absence of motion artefacts and lesion equivalence. Results: Motion artefacts were reduced in 8 cases (better) and were still present in 2 cases (similar). During the development of the algorithm, correction for motion up to 8 mm was possible. If no motion occurred the algorithm did not change the images. There was no additional pseudo lesion which occurred on the post-correction images. Conclusion: Automatic elastic motion correction is capable to improve the quality of dynamic MR-mammograms. Motion correction may avoid motion induced false negative findings due to overlapping of small lesions. No false positive findings were observed on the post-correction images.

Breast waves were displayed within the phase of the MR-image and phase images were used to reconstruct local distribution of elasticity. Three different breast areas were analysed and the average value of elasticity in kPa over the menstrual cycle was determined. Results: All volunteers presented a nearly identical repeating pattern concerning the elasticity over the two cycles. Elasticity of breast parenchyma showed a slow increase until the luteal phase (days 15 -20) and afterwards a significant increase in tissue stiffness up to the secrectory phase (days 21 -27) followed by a clear decrease. The highest values in tissue elasticity were detectable in the central part of the breast followed by retromamillary parenchyma and fatty tissue. Breast parenchyma showed a more than 5-fold increased stiffness immediately premenstrual in comparison to the beginning of the menstrual cycle. Conclusion: MRE shows a menstrual cycle dependency of tissue elasticity in different areas and types of the breast parenchyma.

Value of three dimensional modelling of subtracted images in contrast enhanced breast MRI R.M. Ennis, O. McCormack, P. Gilligan, P. Gilligan, F. Flanagan, M. Kerin, T. Gorey, J.T. Ennis; Dublin/IE Introduction: Subtraction images have contributed significantly to diagnosis in breast MRI. Recently, 3D modelling has become feasible in real time with advances in computer technology. Maximum intensity projection algorithms have been applied to contrast enhanced tumours, but not to pre-post-subtracted images. It is the objective of this poster to evaluate 3D subtraction MR imaging in breast tumours. Patients and methods: 10 patients with palpable lesions were imaged using 3D gradient echo sequences using a bilateral breast coil on a Seimens 1.5 T Magnetom Vision prior to, and post administration of Gd DTPA. The images were transferred to a Vital Images VITREA workstation for 3D reconstruction using a number of algorithms. The images were evaluated by a surgeon, a trainee radiologist, and a consultant radiologist with experience in breast MR. In addition, the axilla was imaged and correlation between histological and MR findings recorded. Results: 3D imaging helped the surgeon to predict the feasibility of conservative surgery more confidently in the pre-operative setting. Diagnosis was not significantly affected by the 3D visualisation in this group of patients, but surgery was more easily planned. In addition, identification of critical lesions such as lymph nodes was improved. Conclusion: This technique has significant potential in MR imaging of the breast and may facilitate breast conserving surgery with adequate margins in selected patients.

Mammography C-0171 Phylloides tumour of breast: radiological semiology of 87 cases R. Jiménez Monreal, R. Ibañez Carreras, A. Mendez Villamón, C. Lidón Lorente, Y. Garcia Hidalgo, F. Solsona Motrel, L. Martínez Comín, E. Mayayo Sinués; Zaragoza/ES Purpose: Phylloides tumour is a rare fibroepithelial tumour with an incidence of 0.3 -1 % of all breast neoplasms. The objective of this study is to determinate the role of radiological studies in its detection. Methods and materials: We present a retrospective study of 87 cases, diagnosed from January 1973 to February 2001, studied by means of mammography, ultrasound and cytology. Tumours were classified according to international criteria in three types: benign, borderline and malignant. Results: The most common finding in mammography was well defined mass that was suspicious in all cases. Ultrasound was performed in 64 cases, and fine needle aspiration under ultrasound guidance in 44 cases (was positive in 54 %). Tumour size greater than 50 mm and alteration of structure, are associated with higher probability of malignancy. The results of cytological study have been: benign (70 %), borderline (11 %) and malignant (18 %). Conclusion: Mammography and ultrasound are of great help in the diagnosis of phylloides tumour. Nevertheless the final diagnosis is based in the hystological analysis.

Spiculate parenchymal distortions in mammography: accuracy of vacuum assisted biopsy L. Apesteguia, C. De Miguel, J. Sáenz, F. Domínguez, I. Pérez-Cabañas, R. Sáez, M.A. Sanz, B. Repáraz; Pamplona/ES Purpose: Spiculate distortions (SD) are Birads-4 lesions that can be associated with invasive or in-situ carcinoma as well as with benign lesions such as radial scar (RS) with or without Atypical Hyperplasia (AH). They are usually managed by surgical biopsy since percutaneous methods have not demonstrated enough accuracy. Vacuum-Assisted Biopsy (VAB) achieves the highest levels of accuracy in microcalcifications and opacities. Our objective was to evaluate the accuracy of VAB in the diagnosis of SD. Materials and methods: From April 99 to August 01, 400 nonpalpable lesions underwent VAB. 24 (6 %) were classified as SD. The patients' ages varied from 34 to 67 years (49.8 ± 9.1). They were biopsied with an 11 G-Mammotome on a Lorad digital stereotaxic table. An average of 10.7 cylinders was obtained. Afterwards, 22 of these lesions were surgically removed. The 2 remaining ones were not operated since they were due to previous biopsies. Results: Post-surgical diagnosis were: 6 invasive carcinomas (IC), 5 RS with intraductal carcinoma (IDC), 4 RS with AH, 6 RS with no AH, 1 sclerosing papilloma. VAB underestimated one IC and two IDC. The remaining lesions were correctly diagnosed. Sensitivity -72.7 %, specificity -100 %, positive predictive value -100 %, negative predictive value -81.2 %, accuracy -87.5 %. Conclusion: Based on our experience, 11 G-VAB can not replace surgical biopsy in these lesions because of low sensitivity, and a high degree of false negative cases. Nevertheless, VAB before surgery can be of interest because surgical therapy can be performed in only one step when the VAB results are those of IC.

withdrawn by author 

We compared the mammograms of 12 patient sent to our facility for an stereotactic core-biopsy. A CR-FFDM of the breast that was going to be sampled was obtained before the interventional procedure in a Delta16 Instrumentarium. Another image was obtained as well with the Camera Coupled Device (CCD) image, to locate the lesion once the patient had been immobilized for stereotactic procedure in the Delta16. The three CC-view images were classified by two different radiologist according to quality, number of microcalcifications and the number of artefacts. Results: The best quality was obtained in CR-FFDM, followed by the SFM, and CCD at the end. The number of microcalcifications was detected in the same order. A similar quality was recorded regarding the artefacts on CR-FFDM, and CCD-DM, while it was worse with SFM. Conclusion: CR-FFDM is better when compared to SFM, and quite similar in terms of diagnostic value, while definition and loss of artefacts is a main goal in searching for microcalcifications.

Inflammatory breast cancer: Evaluation with mammography, US and MRI G. Esen, B. Gurses, N. Erdogan, M. Cantasdemir, A. Altug; Istanbul/TR Purpose: The most striking radiological and clinical feature in inflammatory breast cancer is edema, which may conceal tumour findings and lead to diagnostic problems. In this study, the diagnostic role of mammography, US and MRI were evaluated. Materials and methods: Eighteen patients, 3 of which had bilateral involvement, were examined with mammography, US and dynamic contrast enhanced MRI. MRI images of both breasts were obtained in the axial and/or sagittal planes using FLASH 3D sequence and 1 T magnet. Results: Asymmetric opacity was the most frequent finding in mammography (n: 16); however it was hard to differentiate between tumour infiltration, edema, and plain glandular asymmetry. An ill-defined mass was detected in 9 cases with mammography and in 15 cases with US. Microcalcifications were present in 6 cases. No tumour was detected in 3 cases with mammography (due to dense breast parenchyma) and in 1 patient with US. MRI demonstrated contrast enhancement consistent with malignancy in all cases. The extent of tumour infiltration and edema were best demonstrated with MRI. MRI also revealed spreading of the edema to the inner quadrant of the contralateral breast (which was considered an early sign of lymphatic metastasis) in 3 patients, and unsuspected tumour foci in the opposite breast in 4 more patients. Conclusion: MRI can confirm tumour involvement and demonstrate tumour extent more reliably than other imaging modalities in inflammatory breast cancer. It can be very helpful in patients with vague mammographic and sonographic findings, both for diagnosis and monitoring response to chemotherapy.

Investigation of exposure factors in routine mammography H. Saitoh 1 , T. Fujisaki 2 , K. Watanabe 3 , K. Nishimura 2 , S. Abe 2 , S. Takahashi 1 , K. Fukuda 1 ; 1 Tokyo/JP, 2 Ibaraki/JP, 3 Aomori/JP Purpose: To investigate the exposure factors in order to provide data that may be useful for the improvement of routine mammography in Japan. Material and methods: This study involved 1313 women who had been examined by mammography using a mammographic unit operated by one MRT during a 3-month period at the Cancer Institute Hospital in Japan. The exposure factors for optimum mammography conditions are considered to be dependent on variables of both patient and technical factors. The patient factors investigated were age, projection, compressed breast thickness and degree of compression, and the technical factors investigated were target/filter combination, tube voltage and tube loading. These factors were classified and analyzed statistically, involving the examination of the mean, standard deviation and correlation of factors. Results: The mean compressed breast thickness could be seen to reach a peak at 60 -65 years, and be lowest at 25 -30 years. The mean compressed breast thickness increased gradually in the age range 30 -65 years. The mean compression force also increased gradually with age. The incident air kerma was 10 % less for Mo/Rh and 60 % less for W/Rh compared to Mo/Mo at a compressed breast thickness of 60 mm. Conclusion: A comparison of the present research findings with previously reported results was performed in this study. The W/Rh was found to permit significant dose reductions for thicker breasts.

Accuracy of Tabar's criteria for diagnosis of radial scar and radiologicalpathological correlation J.-M. Miahle, L. Ceugnart, M.-O. Vilain, F. Bachelle, C. Chaveron, S. Taieb, P.E. Besson sr.; Lille/FR Purpose: Analysis of accuracy of the Tabar's mammographic signs in diagnosis of radial scar and radiological-pathological correlation. Methods and materials: 783 patients were seen in our institution for preoperative breast localisation with numeric stereotatic mammography (Senovision, GEMS) between January 1998 and December 1999. 161 stellate lesions were reviewed independently by 2 radiologists without knowledge of clinical history and pathology results. Statistical analysis and pathological correlation of these cases were performed. Results: Sensitivity and inter or intra-observer κ-test were very good but the specificity of Tabar's signs was not accurate (85 -90 %). Among 46 patients with mammographic signs of radial scar and histological confirmation, associated 3 times with carcinoma in-situ and 5 times with atypical hyperplasia. 15 invasive carcinoma (32.5) were found with predominance of lobular (7) and ductal (5) histological subtype. Tubular carcinomas were diagnosed in only 3 cases. The rest of the lesions were benign (11 %). Conclusion: Tabar's sign of radial scar is sensitive and reproducible but not enough specific making surgical biopsy necessary for diagnosis. All histological subtypes of carcinoma were found with tubular carcinoma being the less frequent subtype.

Mammographic changes in postmenopausal women undergoing hormonal replacement theraphy S. Kim, J. Park; Seoul/KR Purpose: The purpose of this study was to illustrate the spectrum of mammographic changes seen in postmenopausal women undergoing hormone replacement therapy (HRT). Methods: Mammographic examinations of 916 patients who underwent HRT at our endocrinologic department were retrospectively reviewed. We identified cases that showed changes on follow up mammography. Results: Mammographic changes were seen on the mammograms of 185 of the 916 patients receiving therapy. These changes include diffuse, focal or multifocal and symmetric or asymmetric increase in breast density, increase in size of benign nodules and development of malignancy. Conclusions: Most common mammographic change is diffuse, symmetric and moderate increase in parenchymal density in women undergoing HRT. Uncommon changes such as focal asymmetric density or suspicious mass are difficult to differentiate from neoplasm. Therefore, it is important for the radiologist to know various mammographic changes during HRT.

Adaptation of BI-RADS system in a population breast cancer screening program with double reading of all mammograms I. Vizcaino, F. Ruiz-Perales, D. Salas, D. Cuevas, M. Escolano, V.B.C.S. Readers Working Group; Valencia/ES Background: The goal of screening is to maximize the viewing time and minimize the time for reporting the findings. Objective: To validate the use of a specific mammographic report (BI-RADS compatible) in a population based screening program with double reading of all mammograms. Material and methods: We use the following descriptions: (A) masses, (B) Calcifications, (C) Architectural Distortion, including the trabecular thickening, (D) Special Cases; the intramammary lymph node is excluded (included as a mass). All the remaining cases such as asymmetric breast tissue, focal asymmetric density and tubular density or solitary dilated duct were included as asymmetry of density, (E) The skin and nipple alterations are categorised separately because they may occur in isolation. (F) All associated findings and multiple lesions are the same category of first description, (G) Non-significant additional lesions; (H) miscellaneous; include artefacts, implants and foreign bodies. The findings are classified in final assessment categories (Category 1: negative; category 2: benign finding; category 3: probably benign finding; category 4: suspicious abnormality; category 5: highly suggestive of malignancy. Category 0 was not used). This system has been evaluated in more than 500000 women screened during 10 years.

The use of a reading system BI-RADS compatible permits a quickly reporting of mammograms and is also useful to perform the Quality Control and Evaluation of Readers in a screening program. The Category 0 is not operative when a double reading system with consensus is used. The agreement of the readers must be evaluated before the consensus.

A program for basic quality controls in mammography: Results in 78 Italian sites C. di Maggio 1 , M. Gambaccini 2 , G. Gennaro 1 , A. Tuffanelli 2 , M. La Grassa 1 , L. Pescarini 1 ; 1 Padova/IT, 2 Ferrara/IT Purpose: To enable radiologists and radiographers to manage basic quality controls in mammography.

The basic mammography quality controls regard automatic exposure control (AEC) device, treatment system, patient dose and image quality. Our team prepared 18 kits containing the instruments for the cited controls and about 100 centres accepted to participate to the project. A site visit was organized in order to provide the operator training. Each kit remained within the site for a 4-week period. Results: AEC checks showed that most mammographic units were able to compensate for voltage changes (86 %), only 55 % for thickness variations. Regarding the treatment conditions, most equipment had acceptable base + fog values and fluctuations, while 27 % were outside the required limits. Average gradient appeared out of bounds in 22 % of the cases. Dosimetric data prove that only few centres delivered large doses. Conclusion: In spite of the annual quality control check, in most sites instruments and procedures for the basic quality tests are not available. The correct employment of simple devices from radiologists and radiographers is easily achievable with a modest training. Results suggest that a greater effort should be made to achieve the quality aim and that the annual controls commonly performed by medical physicists cannot avoid some daily tests.

Mammographic BI-RADS® case report collection: An interactive computer-based tutorial and accreditation tool G. Pfarl, T.H. Helbich; Vienna/AT Learning objectives: To give a summary of the Breast Imaging Reporting and Data System (BI-RADS®; American College of Radiology, 1986) . To teach the mammograms characteristics of breast lesions according to the BI-RAD-System®. Materials and methods: The mammograms of 300 histologically verified cases were prospectively reviewed by two experienced radiologists and classified according to the BI-RAD-System®. Together with the histological diagnosis, the BI-RADS®-morphology and the BI-RADS®-classification (BI-RADS® 0 -5), the mammograms were integrated in a user-friendly, fully interactive computer-surface. To test the effectiveness of the learning tool a post-test for the participant is provided. Conclusion: By interactively reviewing a sufficient number of cases according to the BI-RAD-System® a high didactive effect can be achieved.

Interval breast cancers; try to guess it is true or not S. Kim, J. Park, J. Kim; Seoul/KR Purpose: Interval breast cancers are tumours detected in the intervals between mammographic screenings. It includes true, misinterpreted, and missed carcinomas. True interval cancer does not show abnormal changes on the preceding screening mammograms. Misinterpreted or missed carcinomas show abnormalities on preceding mammograms. This electronic exhibit reviews our 20 cases of interval cancers and provides an interactive testing ability for recognising the lesion on the preceding mammography. Materials and methods: The web based program present clinical history and mammograms of interval cancers and allow the participant to interact by identifying abnormalities on mammograms. Results: The histopathologic types were 18 ductal cancers and 2 lobular cancers. The mean age at the time of diagnosis was 52.8 years. Six tumours were < = 10 mm, eight 11 -20 mm, three 21 -30 mm, one ≥ 31 mm. The mammographic abnormalities were nodule with or without architectural distortion/microcalcifications. Conclusion: Trying to identify abnormalities on preceding mammography of interval breast cancer is helpful in reducing the number of misinterpreted or missed carcinomas.

Miscellaneous C-0183 Digital luminescence mammography (CR) without magnification in clinical routine (n = 1363) R.W.S. Schulz-Wendtland, U.G. Aichinger, M. Säbel, W.A. Bautz; Erlangen/DE Purpose: The digital mammography has the lower spatial resolution in contrast to film screen systems but the advantages of a large dynamic range, reduction of dose, post-processing and CAD. On the basis of our experimental phantom (RMI)examinations it was our aim to investigate the possibility of the digital luminescence mammography without magnification technique (CR) as a diagnostic tool in clinical routine. Methods and materials: The preconditions for the digital luminescence mammography (CR) are the "European Guidelines on Quality Criteria for Diagnostic Radiographic Images". They are fulfilled by the combination of Mammomat 3000N (Siemens), storage phosphor plate IP HRV (Fuji), image reader FFDM-CR (Fuji/ Siemens) and printer TM 8600 (Kodak). We have demonstrated this by our experimental phantom (RMI)-examinations in comparison with the conventional film screen mammography (FS). Results: Between 03/2001 and 08/2001 we examined at our department 1363 patients (preventive examination, screening, aftercare) with the digital luminescence mammography. Dose, contrast and noise were in accordance with the European Guidelines at every time. The higher necessity of time for the development of digital in contrast to conventional analogue mammography hardcopies could be compensated by using 8 cassettes. Conclusion: On the basis of the technical preconditions, the phantom (RMI)-examinations, and the same accuracy in the diagnosis (lesions, microcalcifications) the high resolution digital luminescence mammography (CR) (without magnification technique) can replace the conventional analogue film screen mammography (FS) and be used in clinical routine.

The usefulness of the sentinel lymphnode scintigraphy for breast cancer N. Kamata, K. Abe, Y. Yokoyama, E. Okazaki, Y. Kawawa, S. Fujii, C. Tanaka, M. Kojima; Tokyo/JP Purpose: Minimal invasive operation for breast cancer without lymphnode metastasis has been recently performed. The purpose of this study is to evaluate the role of sentinel lymphnode (SLN) scintigraphy in breast cancer management. Materials and methods: 61 patients (63 breasts and all females) were examined from Nov. 2000 to Aug. 2001. The patients were injected the day before the operation around the tumour subdermally with 74 MBq of 99 Tc-phytate. Scintigraphy was performed 3 hours after injection and marking of the SLN was done on skin. On operation γ-probe was used for detecting the SLN. The number of the SLN was compared with that of the SLN detected by scintigram.

Results: All but one demonstrated SLN. One node was detected in 14 patients. Two nodes were detected in 21 patients. Other patients demonstrated more than 3 nodes. Ten patients demonstrated not only axillary node but also parasternal node. The number of the SLN detected by scintigram was almost same as the number of the SLN detected using γ-probe on operation. Conclusion: The sentinel lymphnode scintigraphy is useful for the detection of the SLN avoiding the axillary dissection in the node negative patients. 99 Tc-phytate is good material for sentinel lymphnode scintigraphy because of high detection of the SLN.

Results: SDA selected several features, extracted by the CAD system, which demonstrated significant predictive power, including the average number of neighbouring MC's, evaluated by the Delaunay triangulation method, reflecting roundness, and the average length of the MC's within the cluster, reflecting size of the MC's. The study demonstrated that an average length larger than 0.41 mm, was associated with malignant pathology 77 % of the time, while 71 % of the benign cases fell below this value. Likewise, in 83 % of the benign cases the average number of neighbours was smaller than 4.57 and among the cases with a greater average number of neighbours, 87 % were malignant. A classification scheme based on the internal cluster organisation and on MC's size, yielded a ROC curve with an Az of 0.86. Conclusion: In the process of developing a CAD system for classification of clustered MC's, it was found that smaller MC's were associated with benignity and that the roundness of the cluster plays a significant role in predicting benignity.

Benign lesions of the breast mimicking cancer: Spectrum of pathologic findings with mammographic and sonographic correlation J.M. Oliver Goldaracena, S. Alonso Roca, S. Hernandez Muñiz, D. Garcia Gonzalez, P. Olmedilla Arregui, M. Argüelles Pinto; Madrid/ES Purpose: The purpose of this exhibit is to review the spectrum of benign lesions of the breast that can show imaging features highly suspicious of malignancy, to correlate the radiologic and pathologic findings and to understand the conservatively treatment in some cases. Methods and materials: We retrospectively reviewed the imaging studies of all benign palpable and non palpable lesions with BI-RADS category 5, biopsied at our institution between 1998 and 2000. They included 25 lesions in 24 patients. Mammography was performed in all cases. Sonography was performed as adjunct to mammography in suspected masses and in palpable lesions with negative mammographic imaging. Excisional biopsy was performed in 22 patients. Core biopsy was performed in 12 patients with concordant diagnosis in the 9 patients who had surgical biopsy. Pathologic features were correlated with imaging findings. Results: The lesions included: radial scar (LEC) (6), sclerosing adenosis (5), fibroadenoma (4), stromal fibrosis (4), mamary duct ectasia (1), atypical ductal hyperplasia (1), fibromatosis (1), tuberculous mastitis (1), diabetic fibrous breast disease (DFBD) (1) and fat necrosis (1). Imaging findings included masses (22) and microcalcifications (3). Three patients (fibroadenoma, stromal fibrosis and DFBD) after core biopsy were treated conservatively with short-term follow-up. Conclusions: Most benign lesions highly suspected of malignancy were masses. Some of them can be treated conservatively after core biopsy. Learning objectives: (1) Review the spectrum of benign lesions of the breast mimicking cancer. (2) To Understand the pathological bases of these entities. (3) To recognise the lesions that can be treated conservatively.

Incidental findings of breast pathology during contrast enhanced chest CT C. Frola, E. Tagliafico, T. Luminati; Genova/IT Purpose: To evaluate the significance of incidental findings in the breast of patients who underwent chest CT for pathologies unrelated to breast disease. Materials and methods: Axial scans of the breast region in chest CT performed from 01/01/2000 to 31/12/2000 were evaluated and the patients with suspected mass in the breast were referred for mammography. Patients with known breast pathology were excluded from the study. Results: Suspected masses of the breast were found in 30 patients. On the basis of physical examination and mammographic results, four of these patients were recommended for biopsy and 3 malignancies (2 invasive ductal carcinomas and 1 adenocarcinoma) and 1 benign lesion (fibroadenoma) were diagnosed. Conclusions: In the evaluation of chest CT in women, attention should be made to the breast region to find out possible signs of an expansive lesion. When a breast mass is incidentally detected, there is a relatively high possibility of malignant lesions (7 %) and all the women with suspected masses must be referred for mammography

Artificial intelligence in analysis of radiological data of the female breasta survey T.W. Vomweg, H.-U. Kauczor, T. Achenbach, A. Teifke, C.P. Heussel, M. Thelen; Mainz/DE Purpose: The field of radiology has been a major beneficiary of rising computer capabilities. The latest approach is the introduction of Artificial Intelligence means. This presentation should give an overview of recently used artificial intelligence methods for analysis of radiological data of the female breast. Materials and methods: Approximately 90 medical journal-articles were analysed and critically reviewed. They were divided due to the type of investigation (Ultrasound, Mammography, MRI and various). Methods of Artificial Intelligence used, features concerned and statistical evaluation were collected and compared. Results: The different investigations show a wide variety of how input data are generated. Most of the authors work with manually extracted data which is timeconsuming and hardly standardized because of high inter-observer variability. Only a few authors use some kind of image pre-processing, although pre-processing could improve the overall-performance of feature extraction systems. Nevertheless, some programs for patient outcome prediction, identification of high-risk patients and even breast tissue dignity prediction perform well showing sensitivities of 90 % or higher. Automatic detection of microcalcifications and masses in mammography is already used in commercially available CAD programs. Artificial Intelligence methods are obviously dominated by feed-forward multi-layered neural networks with back-propagation. Conclusion: Many experimental programs show a wide variety of results which are harder to compare. In general, Artificial Intelligence means are capable to improve analysis of radiological data of the female breast and will receive growing attention. Substantial parts of this investigation were supported by Bracco/Byk Gulden, Milano, Italy.

Breast microcalcifications: Analysis of trace elements by a 2 MeV proton microprobe G. Gennaro, C. di Maggio, A. Galligioni, L. Pescarini, P. Rossi, G. Turco; Padova/IT Purpose: The evaluation of trace elements in breast tissue including microcalcifications by using a proton microprobe. Methods and materials: Some specimens from open biopsies were selected and samples for proton analysis were prepared by cryogenic techniques. Fresh biopsies were flash frozen and microsections freeze-dried before m PIXE analysis. At the National Laboratories of Legnaro (Padova, Italy) a scanning proton microprobe, provided by a 2.5 MV Van de Graaff accelerator is available. All measurements were performed using 2 MeV protons, a beam focusing of 2 × 2 µm 2 FWHM and a current of about 100 pA. The microbeam scanned the target samples by a computer-controlled scanning magnet. X-rays from major and minor elements, mapped as a function of position by a Si (Li) detector, allowed us to identify structures of interest inside the tissue, such as microcalcifications. Subsequently, a new scanning was performed within the region of interest using a higher spatial resolution in order to obtain more detailed elemental information. A second scanning could be carried out after the introduction of an aluminium filter to absorb the major elements and to enlarge the minors. Elemental spectra and maps were analysed offline.

The elemental analysis revealed the presence of heavy metals in regions with high calcium concentration. The detection of heavy elements in the surrounding tissue was significantly lower. Conclusion: A proton microprobe can be usefully employed to study the trace elements in radiological specimens. The next step will be to determine the correlation between trace element analysis and tissue malignancy/benignity.

Breast version June 1993. Because of technical developments of imaging equipment, the protocol has been updated regularly, leading to a completely revised edition in December 2001. Essential alterations are presented. Methods and materials: The method of measurement and limiting values for all test items have been evaluated. The applicability and feasibility of adaptations and additions have been investigated thoroughly before implementation. Results: Methods of measurement have been changed for: sensitometer calibration, HVL, automatic exposure performance, X-ray field geometry and viewing boxes. Limiting values have been adapted for darkroom safelight, stability of the X-ray unit and standard image density. More emphasis is laid on the mean glandular dose instead of entrance dose. In the revised protocol the different kinds of inspections are introduced: inspections for equipment new on the market, acceptance inspections (for new equipment in a screening unit), regular inspections (half-yearly), and occasional inspections (for small changes in equipment). Conclusions: With the adaptations and additions the revised protocol is more appropriate for quality control inspections of modern mammography equipment. For modern equipment some limiting values have been tightened. The limiting values of the 1993 protocol will be applied to existing equipment, to prevent rejection. Newly placed equipment has to apply to the new limits.

Computed tomography (CT) of the breast: Normal and abnormal findings with mammographic and sonographic correlation S. Kim, J. Park; Seoul/KR Purpose: To help in diagnosis of breast lesions by illustrating normal and abnormal conditions of the breast on chest CT and by correlation with mammographic and/or ultrasonographic findings. Methods: We retrospectively reviewed chest CT of 132 patients who also underwent mammography and ultrasonography at the same time. Results: 80 cases were normal, including dense breasts, heterogeneous nodular pattern, glandular asymmetry and postpartum breast. 52 cases had abnormalities consisted of various types of breast cancers, lymphoma, injection granuloma, melanoma, hamartoma, phyllodes tumor, tuberculosis, axillary lymphadenopathy, ductectasia, epidermal inclusion cyst and postoperative changes. Conclusions: CT features of breast lesions are less familiar than mammography or ultrasonography, however, chest CT could show many interesting normal and abnormal conditions of the breast.

Potential of elastography in differentiation of breast tumours: An in vitro experiment J. Lorenzen, R. Sinkus, D. Schrader, M. Lorenzen; Hamburg/DE Purpose: The purpose of this study was to investigate the elastic properties of benign and malignant breast tumours. Material and method: Freshly excised breast tumours were placed on a solid backplane made from aluminium. A piston of fixed diameter was placed on top of the lesion and subsequently lowered. The device allows measuring of the applied force F and the current width L of the compressed region. From these data the elasticity value of each tumour by its initial stiffness at zero strain (Eo) and the nonlinear increase of elasticity as a function of strain can be calculated (a). We analysed the data of 15 malignant and 15 benign tumours, 7 cases of DCIS and 2 cases of fatty tissue and artificial material (PVA). Results: The two artificial materials obtained constant elasticity values as a function of strain. For breast tumours a non-linear increase of stiffness was documented. There was no significant difference between malignant and benign tumours solely on the basis of their basic elasticity at zero strain. Malignant tumours showed a higher increase in elasticity as a function of compression (a) in comparison to benign tumours. DCIS showed intermediate values of stiffness and strain hardening and could not be differentiated from other breast lesions. Conclusion: Malignant and benign breast tumours cannot be differentiated on the basis of their stiffness. Only the combination of elasticity and the degree of strain hardening under compression allow an efficient differentiation.

To create a computerised mammography teaching file for training and evaluation of readers I. Vizcaino, D. Salas, F. Ruiz-Perales, J. Miranda, J. Ibañez, M. Escolano, V.B.C.S. Readers Working Group; Valencia/ES Background: The reading of screening mammograms needs a specific educational method and a quality control process. A continuous performance should be maintained by means of dedicated courses and evaluation of the readers, using a reading system (BI-RADS compatible). Objective: To organise a teaching file of screening mammograms providing a basic method to perform the continuous training and evaluation of readers and permits the accreditation of radiologists Material and methods: We archived 3000 cases distributed in two files: I (General: 2000 cases), and II (Biopsies: 1000 cases) and designed a databases and a specific computer programme that permits selection of the cases from the archive. The archive contains examples of mammograms with findings classified as normal, benign and probably benign, probably malignant and malignant findings (with a Positive Predictive Value for cancer > 70 %). The selection (to extract) of filed cases is made according to: (a) Mammographic description (mass, microcalcifications …), (b) Mammographic categories (normal, benign, probably benign, probably malignant and malignant), (c) Histopathological classification (ductal carcinoma "in situ", infiltrating, etc.). The biopsied cases are stored in a CD-ROM. The training consisted in a free use of the filed cases (the radiologist read the cases during an accumulate period of 50 hours) and attended to the teaching course, conferences and evaluation (on the practical reading of 120 screening mammograms). The results of the use of the mammographic teaching file can be assessed by monitoring the general screening parameters before and after the training of readers.

Effect of different temperature and technology on the histopathologic changes after radiofrequency treatment of breast tissue W. Weiwad 1 , A. Heinig 1 , J. Buchmann 1 , K. Desinger 2 , C. Nowak 3 , S.H. Heywang-Köbrunner 1 ; 1 Halle a. d. Saale/DE, 2 Teltow/DE, 3 Berlin/DE Purpose: To demonstrate the histopathologic changes after RF treatment of breast tissue using different temperature and technology. Materials and methods: We have used either a monopolar triple electrode (Radionics) without probe cooling but internal temperature feed-back, a single needle monopolar probe without probe cooling, a bipolar single needle probe with and another one without probe cooling. Experiments have been performed in vitro on fresh human specimens and in vivo on animals. Results: Using temperatures of 45 -85°C cells could be inactivated as proven by subsequent histopathologic vitality testing. In the mentioned range only little changes were seen on the HE stains, mainly limited to a zone of tissue drying around the probe. The changes decreased with decreasing temperature. The size of tissue inactivation also depended on the temperature, the application time, the type of probe, probe cooling mono/bipolar mode. Examples will be shown. Conclusion: Knowledge that tissue can be inactivated without changing the histopathologic assessment on HE stains may be important for the development of minimal invasive procedures.

Stereotaxic localization of intraductal lesions during galactography M. Calabrese 1 , A. Imperiale 1 , A. Beghello 1 , A. Iozzelli 1 , C. Pinducciu 1 , F. Zandrino 2 ; 1 Genova/IT, 2 Alessandria/IT Purpose: During simple ductal excision distal intraductal lesions could be missed by surgeon. The purpose of our work was to describe the possibility to perform pre-surgical stereotactic localization of peripheral intraductal lesions during galactography. Method and materials: Six consecutive patients (aged 30 -53 a) with hemorrhagic and/or sero-hemorrhagic monorificial nipple discharge underwent galactography. The procedure was performed using a 27 gauge scialographic catheter with a blunt-ended needle (Ranfac, Avon, Mass) and injection of 0.5 -1.0 ml of sterile, water-soluble, nonionic contrast material (Iopamiro 370, Bracco, Milan, Italy) . Images were obtained in the cranio-caudal and true lateral views. The "reperage" was performed immediately after galactography (with the ducts and the filling defects still opacified) using an analogic stereotactic unit (BYM 3D, Metaltronica, Italy) and injection of 1.5 ml of charcoal in sterile saline solution. For all patients histopathologic examination was performed after surgery. Results: Galactography revealed 8 single filling defects in the peripheral branches of the ductal tree. None of the lesions was visible on standard X-ray mammography. In all cases stereotactic localization was possible. All intraductal masses were found in the surgical specimens at hystopathology, which revealed 7 papillomas and one papillary carcinoma. Conclusion: Our preliminary experience demonstrates that localization of peripheral lesions detected with galactography is feasible and allows easy and careful excision.

Mondor's disease: Main imaging features and a review of the literature M. Skilakaki, T. Kratimenos, S. Tsolaki, P. Patouras, E. Robotis, P. Piperopoulos; Athens/GR Purpose: Mondor's disease-superficial thrombophlebitis of the breast-is an unusual and relatively little known vascular entity associated with trauma, surgery, excessive physical activity, dehydration and rarely with breast carcinoma. Our purpose is to describe the mammographic and sonographic findings of this benign condition that should not be mistaken for a malignant breast lesion. Methods and materials: From April 1997 through March 2001 we diagnosed 5 cases of Mondor's disease. The women were aged between 43 and 64 years and presented with a 1 -2 week history of pain, tenderness and palpable cord-like abnormality in the lateral aspect of the breast. Associated skin dimpling was seen in 3 patients. Bilateral mammography and ultrasonography of the palpable lesions were performed in all 5 cases. Results: Mammograms revealed a rope like density in the upper lateral quadrant of the breast. In one case this density had a beaded appearance. Sonography demonstrated a superficial tubular structure filled with low-level internal echoes. Colour-duplex and power-Doppler imaging didn't identify any flow in these structures. The combination of clinical and imaging made the diagnosis of Mondor's disease highly possible and the patients were treated with antibiotics and antiinflammatory agents. On clinical and sonographic follow-up the process resolved completely within 4 to 6 weeks. Conclusion: Clinical and imaging features should be sufficient to make the diagnosis of Mondor's disease and prevent further investigation. Careful evaluation of the mammograms and sonograms for any evidence of a rare associated malignancy is necessary.

Non palpable breast lesion: Data analysis and PPV of our department P. Belli, M. Costantini, M. Romani, V. Valentini, G. Pastore; Rome/IT Purpose: To assess the positive predictive value of mammographic patterns of suspicious nonpalpable breast lesions. To evaluate the incidence of in situ carcinomas and the rate of recurrence and to investigate the operator's performance. Methods and materials: 350 nonpalpable breast lesions detected at mammography underwent stereotactic or sonographic localisation and surgical biopsy. Results: Overall benign/malignant ratio was 0.86 (from 1.94 in the first period to 0.71 in the last period). Very high positive predictive value was observed for spiculated masses and for highly suspicious calcifications. 27 % of all malignant lesions were in situ carcinomas and 75 % of these were identified as highly suspicious calcifications. No case of in situ carcinomas has been detected as irregular mass. PPV for low suspicious calcifications was 34 % confirming the difficulty of its management. 18 % of malignant lesions relapsed. In these cases the rate of lymph node metastasis was very low while there was often an extensive intraductal carcinoma component.

Our study suggest that positive predictive value for every single pattern be continually reassessed based on personal case records rather than on literature data. This holds true especially for microcalcifications. Data on recurrences suggested that these were often due to absence of primary radical treatment.

Axillary masses: Mammographic and sonographic findings S. Chung 1 , E.-K. Kim 2 , K. Oh 2 ; 1 Sungnam/KR, 2 Seoul/KR Purpose: To evaluate the imaging findings of various axillary masses. Materials and methods: The study included 114 patients during a 2-year period who presented with palpable axillary mass or had axillary abnormalities found in breast imaging. Imaging studies comprised a total of 62 mammography, 114 ultrasound, 1 CT, and 2 MR. Histologic confirmation was achieved in 59 patients (13 needle aspiration, 27 core needle biopsy, 21 operation).

Results: Lymphadenopathy was present in 55 cases (benign (n = 35)): 21 nodal hyperplasia, 8 tuberculosis, 6 histiocytic necrotizing lymphadenitis; malignant (n = 20): 9 metastasis from breast carcinoma, 1 lymphoma). 28 cases had accessory breast and its related abnormalities. 17 cases were benign skin lesions. There was also a cystic lymphangioma, a lipomatous tumor, a postoperative benign cyst, and a cellulitis. The differentiation of disease entity among lymphadenopathies was not easy. However, internal coarse calcifications, internal necrosis, and soft tissue oedema were helpful in tuberculosis lymphadenopathy. Histiocytic necrotizing lymphadenitis showed unilateral nodal enlargement with diffuse cortical thickening and normal fatty hilum. Epidermoid cysts showed hypoechoic, and solid or complex-appearing masses which extend into the dermis on US. A Cystic lymphangioma showed characteristic multiloculated cystic mass with thin septa dissecting between normal tissue planes. Lipomas showed typical finding on all images, suggesting fat component. Conclusion: Understanding of the disease spectrum and imaging findings of abnormalities in the axilla is useful for differentiatial diagnosis. Needle aspiration and core needle biopsy under the ultrasound guide are easy and helpful methods for histological confirmation.

World bank sponsored breast screening program in Hungary: Detection of interval cancer in the first three years M. Milics, R. Somogyi, G. Nagy; Zalaegerszeg/HU Purpose: The mammographic screening program sponsored by World Bank was started in Zala County on 1 st January 1998 for women aged 40 -64 with two-year intervals. The purpose of this study was to analyse interval cancers after the first three years. Materials and methods: 25737 women underwent mammographic screening between 1 st January 1998 and 31 st December 2000. A total of 117 malignant tumours were diagnosed. During this period 16 interval cancers were diagnosed. These cases were reviewed by two experienced radiologists who classified them as false negative cases or true interval cancer. We examined their radiographic and histopathological features and the time from the negative screening to the perception of cancer. We analysed the reason for the misinterpretation in false negative cases. Results: 6 -23 months after the negative screening 16 symptomatic women were diagnosed with breast cancer. 9 (56.2 %) were true interval cancer and 7 (43.8 %) false negative cases. 5 of the 16 tumours were masses with or without calcifications, 4 stellate lesions, 3 microcalcifications, 3 architectural distortion and one mammogram was normal. In 15 patients invasive tumours were found by histology and one was in situ carcinoma. The average size of interval cancers was 20.1 mm, and lymph node metastases were found in 37.5 %. The reason for false negative (7) were missed perception (5) Purpose: To develop a non invasive methodology for the exploration of the heart and coronary arteries. Materials and method: 70 patients with heart and coronary artery lesions were examined using the GE's LightSpeed Plus Advantage CT. The acquisition was EKG gated with an iodine injection. To optimize the temporal resolution, the acquisition used a pitch of 1.3 to 1.5 for heart rates of 50 to 60 bpm, pitch of 0.8 for 65 to 75 bpm, and pitch of 1.0 for > 75 bpm at slice thickness of 1.25 mm. The gantry rotation speed of 0.5 s was mostly used. Images were selected in the diastolic phase with minimum motion artifacts. For 3D evaluation of coronary arteries, new post processing tools were utilized: MIP, volume rendering, MPVR, 2D curved reformat and automatic quantification of stenosis. The results were compared to the X-ray coronarography and the myocardium scintigraphy examinations. Results: When comparing to X-ray coronary angiography, cardiac CT shows the ostia and the main branches of the coronary arteries with precision and is able to depict the lumen, calcification and stents. However, further improvement of the spatial resolution, temporal resolution, acquisition volume and time of CT are necessary. Conclusion: Preliminary results using CT for non-invasive cardiac imaging shows future applications of such a technique for the exploration of the heart and the coronary arteries. Further technology improvements will allow cardiac CT to be used as a routine clinical application, in particular for the screening of coronary lesions and for by-pass control.

Optimization of scan parameters to reduce dose for coronary artery calcification scoring (CACS: Agatston Janowitz score 130) using multi detector-row helical CT (MDCT) in comparison with electron beam CT (EBCT) M. Ishifuro 1 , Y. Akiyama 1 , T. Kushima 1 , J. Horiguchi 1 , K. Ito 1 , M. Kudo 2 ; 1 Hiroshima/JP, 2 Tokyo/JP Purpose: Compared to EBCT, MDCT is superior in IQ; there is an issue of dose increase using MDCT. In this study, based on the concept that exposed dose is set higher than necessary, scan parameters to perform examination by EBCT equivalent IQ were considered by using a phantom. CACS results and reduced patient dose were studied. Methods/materials: A 20 cm water phantom was scanned by routine EBCT scan parameters. Then the same phantom was scanned with MDCT with variation of mAs (8 -160 mAs). Within the range the mAs setting required to produce the same image noise level as routine EBCT scan was selected as optimized parameters. Using the optimized parameters, a mock self-made cardiac phantom with embedded calcium was scanned. CACS was performed using both CT methods, and reduced dose was measured by MDCT. Results: MDCT scan parameters of 120 kV, 32 mAs, 2.5 mm TH resulted in the same image noise as using EBCT (P > 0.05). The CACS showed no significant difference in both CT methods. As a result, with the optimized scan parameters for CACS; the patient dose could be reduced up to 1/10 of current dose. Conclusion: By optimizing current MDCT scan parameters to have EBCT equivalent image noise level, the dose could be reduced up to 1/10. CACS results by the optimized scan parameters showed no significant difference to EBCT with P > 0.05.

Assessment of low-density areas in myocardium found on contrastenhanced EBCT in patients with coronary artery disease T. Vesselova, S.K. Ternovoy, V.E. Sinitsyn; Moscow/RU Purpose: Of study was to determine the occurrence and etiology of low-density areas in the myocardium of the left ventricle (LV) in patients with ischemic heart disease after routine EBCT coronary angiography. Material and methods: 66 patients with low-density areas in myocardium were selected from a database of contrast-enhanced coronary EBCTs (56 patients with previous MI and 10 patients without MI, 59 men, 7 women, age 62.7 ± 5.4 years). Imaging was done with Imatron C-150 scanner using injection of 150 ml of iohexol in single-slice mode (40 3 mm slices, 2 mm overlap, 0.1 s each).

In all patients with previous MI, EBCT demonstrated low-density myocardial regions, which corresponded to akinetic or hypokinetic segments of LV myocardium on echocardiography. In 10.7 % of the patients these findings were accompanied by thinning of LV wall and intracavitary thrombus, in other 58.9 % by wall thinning alone. Calcifications and significant stenoses of coronary arteries were found in all patients with previous MI. In 10 patients without MI EBCT detected low-density areas in LV myocardium without wall thinning and signs of scar on ECG and echocardiography. Comparative analysis showed a significant statistical difference between low-density zones and normal myocardium (corr., 32.6 ± 3.7 HU vs 101.9 ± 5.9 HU, p < 0.0001). Conclusion: During contrast EBCT-angiography most of the low-density areas corresponded to sites of previous myocardial infarction. But in some patients they may correspond to hypo-perfused zones of ischemic, viable myocardium. Comparative studies with contrast cardiac MRI should be performed in the near future.

Correlation between local calcification of occluded coronary artery and outcomes of endovascular recanalization M.B. Belkind, V.E. Sinitsyn, N.V. Gagarina, Y.G. Matchin, A.A. Lyakishev, V.G. Naumov, S.K. Ternovoy; Moscow/RU Purpose: Of our study was to estimate the correlation between degree of local calcification of occluded coronary arteries measured by electron-beam computed tomography (EBCT) and outcomes of endovascular recanalization. Materials and methods: 11 patients with 11 coronary artery occlusions were subjected to endovascular interventions. Before the operation all the patients were examined with EBCT (3 mm slices, acquisition time 100 ms, threshold definition of coronary calcification at 130 HU in an area > 1 mm 2 , Agatston calcium score). The calcium score and square of calcification in the occluded segments were calculated. Thereafter we estimated the outcomes of interventions. Results: 7 occluded segments were calcified. The average calcium score was 14.8 ± 23.5 and square of calcification 5.4 ± 9.7 mm 2 . The patients were divided into two groups: with calcium score ≥ 15 (n = 5) and < 15 (n = 6). The recanalization was successful in 1 case of 5 in the first group and in 5 cases of 6 in the second group (p = 0.08). Conclusion: High calcium score (> 15) in an occluded segment of coronary artery decreases the probability of interventional success. These observations may be important in selecting the method for revascularization.

Assessment of aortic valve area with FLASH and trueFISP sequences: Comparison of MRI with echocardiography and catheter G.F. Bachmann, A. John, A. Kluge, C. Müller, T. Dill; Bad Nauheim/DE Purpose: (1) To show that estimation of aortic valve area (AVA) in aortic stenosis is feasible and correlates well with cardiac catheter and TEE. (2) To compare Flash and trueFISP in delineation of the borders of valve orifice in aortic stenosis. Methods: 40 patients underwent MRI, cardiac catheter and TEE for aortic valve stenosis. MRI was performed on a 1.5 T Vision using segmented cine FLASH (TR 80 ms, TE 4.8 ms) and and on a 1.5 T Sonata using True FISP (TR 3.2 ms, TE 1.6 ms). Planimetry was performed on 4 mm slices placed perpendicular to the aortic jet and parallel to the valve level. Planimetry was done by three examiners blinded to each other and to the results of TEE and catheter (inter-observer variability). Evaluation was repeated two months later to determine intra-observer variability. Results: Mean AVA was 0.78 ± 0.2 cm 2 for MRI, 0.96 ± 0.3 for TEE and 0.7 ± 0.3 cm 2 for catheter. MRI correlated well with TEE and catheter. Concerning FLASH, the inter-observer variability was 5.4 % ± 6 % and the intra-observer variability 5.5 % ± 4 %. With the True FISP the variability for inter-observer (4.2 ± 3 %) and intra-observer (4.0 ± 2 %) was better. Conclusion: (1) Evaluation of aortic valve stenosis by MRI is feasible and delivers results comparable to ultrasound and catheter. (2) TrueFISP showed a tendency to more precise estimation of AVA due to better delineation of valve orifice in case of turbulent flow. 

Material and methods: Four different cardiac MSCT protocols with different slice collimation (4 × 1, and 4 × 2.5 mm), and pitch-factor (1.5, 1.8, and 4) were examined. An anthropomorphic Alderson-Rando phantom was equiped with LiF-thermoluminescent dosimeters at several organ sites, and effective doses were calculated using ICRP-weighting factors. A comparison was made to data from standard MSCT of chest and abdomen. Results: Effective dose in different protocols for cardiac MSCT varies from 2.8 to 10.3 mSv (male), and from 3.6 to 12.7 mSv (female). In protocols with thin collimation and low pitch or a combination of several heart examinations, radiation exposure may reach dose values comparable to the effective dose of standard MSCT of the chest (male: 11.9 mSv, female: 12.9 mSv) or the abdomen (male: 16.1 mSv, female: 15.7 mSv). Highest organ doses were found for the female breast (up to 46.6 mGy), and the lungs (up to 36.4 mGy) with surface doses as high as 54.3 mGy. Conclusions: Cardiac MSCT adds significantly to the radiation exposure of patients and can reach the effective dose applied by standard MSCT of chest or abdomen.

Prognostic value of positron emission tomography with [1-11 C]-butyrate for evaluation of recovery left ventricular dysfunction after surgical revascularization D.V. Ryjkova; St. Petersburg/RU Aim of this study was to assess prognostic value of PET and Sodium [1-11 C]-butyrate ( 11 C-butyrate) for recovery of left ventricular (LV) dysfunction after surgical revascularization (SR) in patients with coronary artery disease (CAD). Methods: We examined 18 patients (male, mean age 42 ± 8 a) with CAD and LV dysfunction at rest. Regional and global LV contractility were evaluated by echocardiography (ECC) twice: before and 5.8 ± 0.5 months after SR. PET and 11 C-butyrate assessed oxidative metabolism rate as a myocardial viability marker. In order to evaluate an increase of global LV function all patients were divided into two groups: patients with more than two viable neighboring segments (the first group), patients with two and less viable neighboring segments (the second). Results: Of a total number of 288 myocardial segments, 109 segments with abnormal rest wall motion were analyzed by ECC. PET with 11 C-butyrate sensitivity, specificity and diagnostic accuracy were 92 %, 91 % and 92 % respectively to predict regional myocardial dysfunction improvement after SR. The sensitivity was higher for hypokinesia (95 %) compared with akinesia (75 %). Specificity was lower for hypokinesia (80 %) than for akinesia (94 %). The diagnostic accuracy was identical for all alteration kind of regional myocardial contractility (91.8 % and 91.6 % respectively). Global LV function significantly increased in patients with more than two viable neighboring segments after SR (p < 0.05). Conclusion: PET with 11 C-butyrate is shown to be a feasible method for the evaluation of myocardial viability and prediction of LV dysfunction improvement after SR.

MRI comparison of systemic ventricular performance in mustard/senning repaired patients and healthy volunteers E. Laffon sr., M. Jimenez sr., V. Latrabe sr., D. Ducassou sr., A. Choussat sr., R. Marthan sr., F. Laurent sr.; Pessac/FR Purpose: To non invasively compare the mechanical performance of the systemic right ventricle (RV) in Mustard or Senning repaired (MSR) patients with that of the systemic left ventricle (LV) in healthy young adults at rest. Methods and materials: Velocity-encoded MR imaging was performed in 8 patients (16 -23 years of age) late after a Mustard or Senning correction, and in 8 healthy volunteers (21 -28 years of age). Measurements were achieved at the upper part of the ascending aorta within a single slice. Both aortic cross-sectional area (CSA) and blood flow variations versus time were recorded over a complete cardiac cycle with a 30 ms time of resolution. Results: Significant differences in aortic CSA and in aortic systolic blood flow rate have been found between MSR patients and healthy volunteers. At rest, the systemic RV mechanical power and work of MSR patients have been estimated to be 80 % and 81 % on average those of the systemic LV of healthy volunteers respectively.

The mechanical performance of the systemic RV in MSR patients has been non invasively quantified using velocity-encoded MR imaging, and has been found significantly lower than that of the systemic LV in healthy volunteers at rest.

Influence of coronary lesions severity on diagnostic value of contrastenhanced electron beam computed tomography D. Ustuzhanin, T. Vesselova, V.E. Sinitsyn, S.K. Ternovoy; Moscow/RU Purpose: The aim of our study was to compare the diagnostic value of contrastenhanced electron beam CT of coronary arteries (EBCT) for detection of different grades stenoses (> 50 %, > 75 % and occlusions) in patients with coronary artery disease (CAD) using conventional coronary angiography (CA) as the "gold standard". Materials and methods: 37 patients (34 men and 3 women, mean age [± SD] of 55 [± 10] years) underwent EBCT and CA in 1998 -2000 were included in a retrospective case series study. 100 of 148 proximal-middle segments (left main, left anterior descending, left circumflex and right coronary artery) had no significant stenoses, 48 (32 %) had stenoses > 50 %, 31 (21 %) had stenoses > 75 % and 18 (12 %) had occlusions as determined by CA. Results: 7 (5 %) segments were unevaluable by EBCT. Sensitivity and specificity in the remaining segments were 89 % (95 % confidence interval, 79 % to 96 %) and 97 % (95 % confidence interval, 92 % to 99 %), 63 % (95 % confidence interval, 43 % to 79 %) and 99 % (95 % confidence interval, 96 % to 100 %), 74 % (95 % confidence interval, 50 % to 89 %) and 100 % (95 % confidence interval, 98 % to 100 %) for detection of stenoses > 50 %, > 75 % and occlusions, respectively. There was no significant difference between the sensitivity or the specificity of EBCT in detection of stenoses > 50 %, > 75 % and occlusions. Conclusions: Severity of coronary lesions (stenoses > 50 %, > 75 % and occlusions) does not influence significantly the diagnostic value of contrast-enhanced electron beam computed tomography.

Comparison of coronary calcium scores and reproducibility between clinical high dose and simulated low dose protocols P.C. Johnson 1 , D.E. Smith 1 , D.D. Matthews 1 , C. Meyer 2 ; 1 Highland Heights, OH/US, 2 Indianapolis, IN/US Purpose: Precise calcium scores with multi-slice spiral CT are achieved using high dose scanning protocols to reduce image noise and clearly delineate calcium deposits. As a screening technique, calcium scoring must be performed with radiation doses as low as reasonably achievable. We compare high dose and simulated low dose scanning protocols for accuracy and reproducibility. Methods: 20 patients were recruited for quantification of calcium deposits in the coronary arteries. Using a quad slice CT scanner (MX-8000, Marconi Medical Systems), two scans were obtained of each patient using an axial prospective ECG acquisition technique at 165 mAs. Simulated low dose (55 mAs) images were generated by adding a noise map to each high dose image. Each set of images was scored using three methods: (1) total volume; (2) maximum, step, area, threshold = 130; and (3) average, continuous, area, threshold = 130. The high dose and simulated low dose calcium scores and variabilities were compared. Results: For the high dose scan, the mean scores for three scoring methods were 422, 540 and 351, respectively. For the low dose scan, the mean scores were 432, 549 and 358, respectively. The average difference between the high and low dose scans was 5 % for all scoring methods. For the high dose scan, the mean variabilities for the three scoring methods were 12 %, 15 % and 15 %, respectively; while for the low dose scan the mean variabilities were 11 %, 15 % and 14 %, respectively. Conclusion: Low dose scanning protocols are reliable and reproducible compared with high dose protocols for coronary artery calcium scoring.

Diagnostic value of contrast-enhanced electron beam computed tomography for detection of coronary arteries stenoses in patients with unstable angina D. Ustuzhanin, T. Vesselova, V.E. Sinitsyn, S.K. Ternovoy; Moscow/RU Purpose: The aims of our study were (1) to compare the diagnostic value of contrast-enhanced electron beam CT of coronary arteries (EBCT) for detection of stenoses > 50 % in patients with unstable angina and stable coronary artery disease (CAD) and (2) to determine the positive and negative predictive values of EBCT in patients with unstable angina using conventional coronary angiography (CA) as the "gold standard". Materials and methods: 37 patients (55 ± 10 years) who underwent EBCT and CCA were included in a retrospective case control study. Patients were divided in two groups: Group A (19 patients) included patients with unstable angina and

Group B (18 patients) included patients with stable CAD. 25 (33 %) and 23 (32 %) of the 76 and 72 proximal-middle segments, had stenoses > 50 % as determined by CA in Group A and Group B, respectively. Results: The sensitivity and the specificity of EBCT for stenoses detection were 91 % (95 % CI, 73 % to 99 %), 98 % (95 % CI, 89 % to 100 %) and 88 % (95 % CI, 72 % to 97 %), 96 % (95 % CI, 92 % to 99 %) in Group A and Group B respectively. There was no significant difference between the two groups in terms of the sensitivity or the specificity. The positive and negative predictive values of EBCT for stenoses detection in patients with unstable angina were 91 % (95 % CI, 73 % to 99 %) and 94 % (95 % CI, 84 % to 98 %) respectively. Conclusions: Diagnostic value of EBCT for the detection of stenoses > 50 % in patients with unstable angina and stable coronary artery disease does not differ significantly.

Right ventricular hypertrophy in the athlete's heart: Results of cardiac MRI examination in endurance athletes G.K. Schneider 1 , K. Altmeyer 1 , J. Scharhag 2 , V. Rochette 1 , A. Urhausen 2 , W. Kindermann 2 , B. Kramann 1 ; 1 Homburg a. d. Saar/DE, 2 Saarbrücken/DE Introduction: In contrast to left ventricular hypertrophy of the so called athlete's heart in endurance athletes there is little data available about the extent of the concomitant hypertrophy of the right ventricular myocardium. Materials and methods: 23 male athletes and 25 male nonathletes were included in our study. MRI was performed on an 1.5 T scanner applying serial short-axis ECG-gated T1w enddiastolic images as well as short axis cine images covering both ventricles with a slice thickness of 6 mm. To determine absolute and relative RVM and LVM in MRI, the even summation of slices method for myocardial volume measurement was used defined by the endo-and epicardium in short axis images. Results: Absolute LVM and RVM was significantly greater in athletes (199.5 ± 19.9 g and 75.9 ± 9.9 g) compared to the nonathletes control group (148.9 ± 17.1 g and 58.7 ± 13.1 g) (p < 0.001). The same holds true for the relative LVM (2.9 ± 0.2 g/kg vs 2.1 ± 0.2 g/kg respectively 107.1 ± 6.2 g/m 2 vs 78.8 ± 6.7 g/m 2 (p < 0.001)) and RVM (1.1 ± 0.1 g/kg vs 0.8 ± 0.2 g/kg respectively 40.7 ± 3.7 g/m 2 vs 31 ± 6.2 g/m 2 (p < 0.001)). There was no significant difference concerning the ratio of LVM to RVM between A and NA (2.6 ± 0.2 in A and 2.6 ± 0.4 in NA). Conclusion: Absolute as well as relative LVM and RVM is significantly increased in highly trained endurance athletes. Our data show that a physiological concomitant hypertrophy of the right ventricle is present, since the relation between LVM and RVM remains unchanged when both groups are compared, verifying the hypothesis of the harmonic growth of the athlete's heart.

Quantitative coronary angiography in analysis of progression and regression of coronary artery disease in relation to coronary stenosis morphology J.D. Saponjski, M. Ostojic, B. Beleslin, M. Nedeljkovic, L. Blazic; Belgrade/YU Objective: The aim of this study was to analyze progression and regression of coronary stenosis in relation to stenosis morphology. Methods: The study group consisted of 53 patients (43 male, 10 female; mean age 54 ± 11 years) with 66 coronary lesions, whose symptoms were an indication for first and second coronary arteriography. Coronary stenoses were analyzed by quantitative coronary arteriography including percent diameter stenosis (%DS) and changes in obstruction diameter between the two arteriographies. According to the Ambrose angiographic lesion morphology in 4 groups the follow-up period between first and second arteriography were similar for all groups (I, 8 ± 9 months; IIa, 11 ± 10 months; IIb, 7 ± 8 months; III, 6 ± 5 months; p = ns). Results: Progression of coronary artery disease was identified in 66 %, 75 %, 80 % and 100 % of lesions in Ambrose groups I, IIa, IIb, and III, respectively. On the contrary, regression of coronary stenosis was documented in 33 %, 25 %, 20 % and 0 % of lesions in groups I, IIa, IIb, and III respectively. Comparing the lesions with non-significant and significant stenosis (cut-off point 50 % DS), progression of coronary stenosis was higher for the lesions with DS 50 %), reaching statistical significance in group I (I, +0.52 ± 0.55 vs −0.24 ± 0.32 mm, p < 0.01; IIa, 0.61 ± 0.80 vs 0.13 ± 0.32 mm, p = ns; 0.66 ± 0.69 vs 0.33 ± 0.56 mm, p = ns). Conclusion: Coronary lesion morphology of simple type was associated with lower rate of coronary stenosis progression. Coronary lesions of all morphological types tended to exhibit higher rates of progression in quantitatively less severe coronary stenosis. The aim was to compare diagnostic value of low DOB-RNV and low DOB-ECHO for the prediction of functional recovery of viable myocardium in the medium term follow up. Patients and methods: 20 patients (18 male; 51 ± 10 years) with previous myocardial infarction and resting wall motion dyssynergy were studied before angioplasty of infarct related artery (IRA), by RNV and ECHO at rest, as well as during drug infusion (10 µg/kg/min over 5 min). RNV as well as ECHO was repeated at rest, 12 weeks after successful angioplasty. Five percent increase of regional ejection fraction (REF) by RNV was used as criterion for functional improvement of infarcted regions. By ECHO, viability was defined as improvement of wall thickening or contractile improvement of grade one or more, utilizing wall motion score index (WMSI). Results: Out of 180 examined (20 × 9) segments by RNV, 51 were dyssynergic and they had abnormal REF (29 ± 10 %). Out of these 51 segments functional improvement was documented in 33 on low DOB. Sensitivity for predicting functional recovery after 12 weeks follow up was 63 %, and specificity was 77 %. WMSI assessed by ECHO was 1.35 ± 0.22, 1.16 ± 0.20 and 1.13 ± 0.14 for rest, low DOB and rest follow up, respectively (p < 0.05). Sensitivity of low DOB-ECHO for predicting functional recovery was 80 %, and the specificity was 90 % (p = ns vs low DOB-RNV). Conclusion: Both techniques, RNV and ECHO could serve as predictors of myocardial viability in medium term follow up. It is suggestive that DOB-ECHO might provide even more valuable prognostic information on myocardial viability.

Clinical application of cardiac MR imaging: When, how to do, and what to look for R. Soler, E. Rodríguez, C. Remuiñán, M. Santos; La Coruña/ES Purpose: To review when a cardiac MR study should be performed, how to do the examination and, what are the hallmarks to look for in clinical application of cardiac MR. Materials and methods: We identified the morphologic and functional MR findings important to decide medical, surgical or percutaneous treatment in 522 patients with congenital heart diseases, myocardiopathies, arrythmogenic right ventricular dysplasia, heart masses, infections, valvular and pericardial diseases. Specific sequences, optimal MR protocols for the most common entities and representative examples will be presented. Results: Black blood T1-W images were used to evaluate the morphology. Gradient-echo (GE) cine-MR should be performed to define myocardial contraction and valve function in intrinsic heart planes. Multislice multiphase GE sequences should be acquired to quantify ventricular volumes and myocardial mass usually in a short axis plane. Contrast enhanced 3D MR angiography are useful to analyze the complex anatomy, the vessels and the surgical procedures in congenital diseases. Tissue characterization should be performed with T2-W and contrast enhanced SE T1-W in heart masses, and in some myocardiopathies. Conclusion: Cardiac MR examination could be done to answer clinical questions in a time-effective way if the study is performed focusing on the hallmark of the disease. The radiologist will be able to exploit this technology to its full potential as a noninvasive cardiac imaging modality and to incorporate it into the clinical routine.

Prospective blinded study in the evaluation of coronary artery stenosis with retrospective ECG gated multislice CT at 4 ml/s and 60 ml at 2.5 ml/s). Once acquired, images were sent to a workstation where they were reprocessed and quantified. The stenosis quantification with MSCT was done in each coronary artery taking an average of five measurements in curved MPR and strict coronal and sagittal views. In the last two, the measurements were done by means of diameter and area, in order to reduce variability. DA was measured by QCA. Statistical Analysis: the 95 % confidence intervals (CI) for the proportions were calculated using the exact binomial method. Results: The total true-positive results were 72, true-negative results 190, falsepositive results 14 and false-negative results 15. Sensitivity was 83.9 % (CI: 75.5 -89.9), specificity 91.2 % (CI: 86.4 -94.5), positive predictive value 83.2 % (CI: 74.7 -89.3) and negative predictive value 91.6 % (CI: 86.9 -94.8). Conclusion: MSCT is an interesting new approach for noninvasive detection of coronary artery disease with high results of Sensitivity and Specificity. More studies have to be done to validate these results.

T2 proton relaxation time measurements in -thalassemia patients using magnetic resonance imaging (MRI) pulse sequences G. Kotoulas, I. Seimenis, P. Baras, K. Horomidou, M. Tsakatakis, M. Gavra, E. Katsianou, D. Triantafillou; Athens/GR Purpose: Various MRI pulse sequences have been employed in the measurement of T2 relaxation time in the heart and liver of -thalassemic patients undergoing multiple blood transfusions. In this work a conventional SE technique is compared to a TSE technique and the importance of various sequence parameters is discussed. Materials and methods: T2 measurements in the heart and liver of 30 patients were obtained at 1.5 T (Philips ACS-NT) using a 2D, 8-echo, Hahn SE sequence (TR = 2000 ms, TEi = 20 ms) and a 2D, 2-echo, Carr-Purcell-Meiboom-Gill TSE sequence (TR = 2000 ms, TE1 = 8 ms, TE2 = 40 ms). Serum ferritin concentrations were compared to the obtained T2 values. Results: In many patients a marked discordance between liver and heart T2 measurements was noted indicating the unpredictability of cardiac iron deposition. The TSE sequence provides higher accuracy in quantifying abnormal iron tissue levels compared to the SE sequence. When the results of all patients were examined, no significant correlation could be found between heart or liver T2 and serum ferritin. A weak correlation (r2 = 0.51, p = 0.05) between T2 values obtained using the TSE sequence and serum ferritin was found only for the group of patients with ferritin levels < 1500 ng/ml. Conclusions: When measuring T2 in the liver and heart of -thalassemic patients, it is important to use a sequence which compensates for 180° pulse imperfections. Spreading out echo times evenly over the range of the measured T2 values improves quantification of severe iron overload, while echo times well outside that range do not offer any further improvement.

The use of an active image filter for cardiac radiology education and research J. Revell, C. Burgess, A. Ederies, P. Davison, M.R. Rees; Bristol/GB Purpose: Cardiac radiology has been relatively under investigated. With increased application of modern radiology techniques to the heart there is a need for increased teaching in cardiac radiology. This study was designed to investigate the utility of an active Internet image browser facility for cardiac radiology education and research. Materials and methods: The browser filter featured a facility for fast and effective Internet searching of images in a user-friendly matrix and their related web links. The images were generated by processing of multiple synchronous threads in response to key word searches in Google. The program could be modified to search for colour or black and white images, and a variety of image formats. The program was used to search a variety of cardiac radiology topics, including imaging of coronary arteries, pericardial disease, cardiac tumours, valve disease and ventricular dysplasias. This methodology was compared to conventional searching using Google over a period of 15 minutes per topic. Results: In each search relevant images and associated web sites were quickly downloaded and from the images the browser could be pointed to the associated articles. Conventional searching required considerably more time and resulted in fewer relevant images and articles. All active Internet filter searches took less than 5 minutes from activation to production of final images. Conclusion: The use of the filter was user friendly and resulted in fast down load of relevant images and articles to the topic under investigation. This has a promising potential role in teaching radiologists cardiac radiology.

Evaluation of impaired left ventricular function by cardiac MRI -pictorial review of differential diagnoses G.K. Schneider, I. Janzen, K. Altmeyer, R.M. Seidel, M. Boehm, B. Kramann; Homburg a. d. Saar/DE Purpose: Impaired left ventricular function represents a frequent echocardiographic finding. Its symptoms have an important impact on patients life quality. As the therapeutic strategies differ considerably an early and precise diagnosis should be made to prevent further damage to the myocardium and relevant comorbidity. Methods: Cardiac MRI offers a combination of morphologic and functional parameters, which can be easily accomplished during one examination session. By means of ECG-gated breathhold single slice T1-and T2w-images the myocardial texture can be evaluated and possible edema or infiltration can be detected. CINE imaging gives an overview of cardiac blood flow and contractility during the complete cycle of cardiac movement and GRID-or STRIPE-tagging allows reliable detection of hypokinetic areas. Results: Examples of infiltrative diseases such as amyloidosis, sarcoidosis or lymphoma will be presented along with examples of myocarditis induced cardiomyopathy, cardiomyopathy in transplant rejection and focal hypokinesia after infarction. Conclusion: Cardiac MRI represents a valuable tool to further characterize the possible cause of global or focal hypokinesia complementary to echocardiography and cardiac catheterization. The knowledge of focal or diffuse involvement of the myocardium as well as a possible biventricular disease may contribute to further reduce the number of potential DDX and can be used to plan myocardial biopsy.

Diagnosis of a postsurgical pseudoaneurysm in Shone syndrome by cardiac magnetic resonance A. Meduri 1, 2 , R.K. Razmi 2 , V.K. Rathi 2 , L. Natale 1 , G.M. Pohost 2 ; 1 Rome/IT, 2 Birmingham, AL/US A 34-year-old male was admitted with increasing exertional dyspnea. He was born with shone syndrome and an aortic coarctation was repaired within the first year of life. At 7 he underwent mitral and aortic valvuloplasty and at 15 aortic valvulotomy and aortoplasty. At 12 an ascending aortic aneurysm was repaired with reimplantation of the coronary ostia and mitro-aortic valve replacements. At 31 he was admitted with hemoptysis but discharged after a negative bronchoscopy and V/Q scan. Exertional dyspnea increased and cardiac catheterization and echocardiography showed pulmonary (mean PA = 46 mmHg) and right ventricle hypertension; an aortic pseudoaneurysm compressing the left atrium was demonstrated. On angiography the left circumflex artery originated from the right coronary artery but the left main or left anterior descending artery were not visualized. MRI and MRA were performed showing the tube graft in the ascending aorta connected to a large pseudoaneurysm whose ostium was located immediately above the aortic valve at the usual site of left main coronary artery, not visualized. It compressed both atria and SVC and displaced and mildly compressed the superior right pulmonary artery. The main pulmonary artery was enlarged (43 mm). Moreover, a mild aortic re-coarctation (12 mm) was evident. The ascending aortic pseudoaneurysm was repaired; the left coronary artery anastamosis had completely dehisced with a 5 mm separation between the hole in the tube graft and the left coronary ostium. The left main coronary artery was then anastamosed to the ascending aortic graft using a 7 mm woven graft. The patient recovered completely and was discharged.

Basic evaluation of temporal resolution by different algorithms for ECGgated high resolution CT of the lung H. Zhang 1 , Z. Pan 1 , Y. Shen 2 , Q. Song 1 , L. Du 1 , J. Yi 1 , J. Hao 1 , G. He 1 , K. Chen 1 ; 1 Shanghai/CN, 2 Tokyo/JP Purpose: In the multi slice CT, cardiac motion artifact with lower temporal resolution is the big problem for HRCT. This paper aims to display basic evaluation of temporal resolution by different algorithms for ECG-Gated lung high resolution CT. Method/materials: Cardiac motion phantom studies and patient studies were examined on a MDCT scanner (GE LightSpeed QX/I, 0.8 s rotation speed) using HRCT and retrospectively ECG gated scan modes (4 × 1.25 mm collimator). Based on the ECG information, diastolic phase with cardiac motion artifact free was selected. Also, two high temporal resolution algorithms (Current segment algorithm; 400 ms; and multi sector algorithm; 130 ms) were tested for evaluation of temporal resolution and image quality. We have assessed improvement of image quality of lung HRCT by comparison of the results using two algorithms.

Results: In the pulsating cardiac phantom study, it was showed that the MSR (multi sector algorithm) algorithm (Maximum effective temporal resolution; 130 ms) can dramatically reduce cardiac motion artifact more than the Current Segment (CS) algorithm (effective temporal resolution: 400 ms) and diastolic phase can provide good image quality, free from artifact. The relationship of temporal resolution and artifact reduction was evaluated. In the patient study, the MSR algorithm can significantly reduce artifacts caused by cardiac motion (distortion of pulmonary vessels, double images, or blurring of the cardiac border), more than the CS algorithgm. Conclusions: Proposed MSR algorithm can improve image quality of lung HRCT scans by reducing cardiac motion artifact and increasing temporal resolution.

Right ventricular dysplasia in patients with left-bundle-brunch (LBB) configured ventricular arrhythmia G.F. Bachmann, W. Ricken, T. Dill, A. Kluge, C. Hamm; Bad Nauheim/DE Purpose: Right ventricular (RV) dysplasia of the heart has been defined in MRI by several major and minor findings which may be a source of arrhythmia. Our aim was to estimate whether LBB configured ventricular arrhythmia is combined with a high risk of right ventricular dysplasia. Methods: 327 patients with LBB configured ventricular arrhythmia were examined by MRI (1.5 T Vision and Sonata) using the following sequences: (1) segmented 2D flash sequence (TR 80 ms, TE 4.8 ms, flip angle 20°) to assess the contractility of RV myocardium, (2) dark-blood prepared T1 weighted TSE in breath-hold (TR 0.9 × RR, TE 7 ms) with and without fat saturation to define fatty inclusions; (3) inversion prepared TSE (TIRM) in breath-hold (TR 0.9 × RR, TE 8 ms). MRI was finally compared with electrophysiological investigation (EPI) and echocardiography. Results: The origin of LBB arrhythmia could be localized by EPI within the right ventricle in 115/327 patients. 14 patients fulfilled at least one criterium of right ventricular dysplasia in MRI: 6 patients showed aneurysmal segments of the right ventricle combined with wall motion abnormalities, 7 patients had dilated RVOTs and 5 patients had abnormal trabecular differentiation. In 4 cases fatty inclusion were detected within RV myocardium. Using echocardiography signs of RV dysplasia were found in 8 of these 14 cases.

(1) MRI should be used to demonstrate RV dysplasia only in cases when prior EPI defines the focus of arrhythmia within the right ventricle. (2) MRI is superior to ultrasound in defining the signs of right ventricular abnormalities.

Noninvasive measurement of absolute levels of cardiac high-energyphosphate metabolites in dilated cardiomyopathy (DCM) by 31 P-MR spectroscopy A. Hansch, R. Rzanny, J.-P. Heyne, U. Leder, W.A. Kaiser; Jena/DE Purpose: The myocardial phosphocreatine (PCr) is the energy reserve of myocardium. We examined the correlation between impaired cardiac high-energy phosphate metabolism (PCr) and left ventricular end-systolic volume (LVEF) in patients with dilated cardiomyopathy (DCM). Method/materials: Myocardial 31 P magnetic resonance (MR) spectra were obtained at 1.5 T whole body scanner by chemical shift imaging in 10 healthy volunteers and 10 patients with DCM (cardiac catheterisation: normal coronaries, reduced LVEF, typical clinical findings). Absolute levels of PCR and ATP were determined by using a reference solution. Left ventricular end-systolic volume (LVEF) was measured by cardiac catheterisation Results: Patients with dilated cardiomyopathy were divided into two groups: 5 patients with moderate DCM (LVEF > 30 %) and 5 patients with severe DCM (LVEF < 30 %). Absolute PCR levels and PCR/NTP ratio were significantly lower in patients with severe DCM (LVEF < 30 %, p = 0.02) compared with healthy volunteers. Between PCR/ATP ratio and LVEF a linear correlation was found (Pearson coefficient 0.86). Conclusions: 31 P-MR spectroscopy can detect abnormal high-energy phosphate metabolism in patients with advanced heart failure due to DCM (LVEF < 30 %). The abnormalities correlate to hemodynamic parameters. We found no significant change in the high energy phosphate metabolism patients with mild DCM.

Pitfall of the evaluation of multidetector-row CT coronary angiography: The cross of the greater cardiac vein over the coronary artery K. Sato, M. Jinzaki, Y. Tanami, K. Matsumoto, H. Shinmoto, S. Kuribayashi, K. Sasaki; Tokyo/JP Purpose: The volume rendered images of MDCT coronary angiography often show crosses of the greater cardiac vein (GCV) on the coronary artery, and the cross point makes it difficult to estimate coronary artery stenosis in detail. We evaluated the frequency of this crossing. Material and methods: Fourteen patients were examined on a multidetector-row CT (GE LightSpeed Plus). 100 ml of 370 mg I/ml contrast material was injected. Raw helical CT data and ECG tracings were combined to reconstruct volume rendering images of the left coronary artery (retrospective gating, 70 % of the R-R interval was used). Processed three-dimensional images were reviewed and the crossing of GCV on the coronary arteries (left anterior descending artery (LAD), first diagonal (D1), second diagonal (D2), and circumflex (LCX)) were recorded. Axial images were referenced to see if the GCV runs over or under the arteries. Results: The cross point of LAD and GCV was seen in seven (50 %) of 14 cases. Among these, GCV crossed over LAD in three (21 %). The cross of D1 and GCV in 13 (93 %), and GCV over D1 in two (14 %). The cross of D2 and GCV in eight (57 %), and GCV over D2 in two (14 %). The cross of LCX and GCV was seen in all cases, and GCV over LCX in 13 (93 %). Conclusion: GCV crossed over LCX in almost all cases and crossed over LAD, D1, and D2 in some cases. The cross point of GCV over the coronary artery is not a rare pitfall on volume-rendered MDCT coronary angiography.

Ejection fraction calculations using multi-slice CT: A comparison of manual and automated contouring P.C. Johnson 1 , R.C. Gilkeson 2 , D.E. Smith 1 , M. Vembar 1 , S. Chandra 1 ; 1 Highland Heights, OH/US, 2 Cleveland, OH/US Purpose: Retrospectively reconstructed cardiac CT angiography (CTA) studies provide high-resolution volume images of the heart. Extraction of the left ventricular volume provides clinical information such as stroke volume and ejection fraction. Calculation of these physiological parameters must be fast and accurate. We propose an automated method and compare manual and automated contouring techniques for calculating the left ventricular volume, stroke volume and ejection fraction. Method: 25 patients were recruited for the cardiac CTA study. Each patient was scanned on a 4-slice CT scanner (MX-8000, Marconi Medical Systems) and 8 phases of the cardiac cycle were reconstructed (temporal resolution 250 ms). The ventricular volume for each phase was calculated using a manual contouring and an automated technique. The automated technique involved orientating the volume to the short axis, applying a threshold-based region-growing algorithm, morphological filtering and manually editing contours near the aortic valve. The stroke volume and ejection fractions were calculated from the volumes. Comparisons of the results were drawn between the two techniques. Results: The mean time to manually contour an entire CTA data set (100 images/ phase) for an experienced user was approximately 2.5 hours. The mean time to automatically contour the same data set was 20 minutes. The mean difference in ventricular volumes, stroke volume, and ejection fraction between manual and automated contouring was 7.2, 9.5, and 4.8 %, respectively. Conclusion: Preliminary results show that an automated ventricular extraction algorithm provides accurate measurements of ventricular volume, stroke volume and ejection fraction at a fraction of the time consumed by manual contouring.

Cardiac MR in the evaluation of left ventricular aneurysm of the heart: Value of cine-MR, perfusion and late enhancement sequences A. Kluge, T. Dill, C. Breidenbach, W.-P. Kloevekorn, G.F. Bachmann; Bad Nauheim/DE Purpose: To evaluate the role of different cardiac MRI techniques in the planning of surgical therapy in patients with left ventricular aneurysm. Methods: 51 patients with reported left ventricular aneurysm and planned resection were examined using TrueFisp (SSFP) multislice cine sequences for left ventricular volumetry and for evaluation of segmental left ventricular function. Ischemic areas were targeted using first pass perfusion in rest and late enhancement sequences. Examinations were analysed and quantified for regional akinesia, lack of systolic wall thickening and systolic bulging in cine-sequences. Perfusion defects and late enhancing areas were evaluated after administration of contrast media. Results: Six patients showed only regional hypokinesia but no evidence of myocardial necrosis (late enhancement, perfusion defect) and no LV-aneurysm. The areas of necrotic myocardium of the remaining 45 patients were located mostly on the anterior wall of the LV and at the apex. 17 patients showed subendocaridal and 19 patients transmural extension of necrotic myocardial areas. Late enhancement demonstrated the septal and lateral extension of necrotic areas. Differing areas of akinetic myocardium and late enhancing areas allowed the differentiation of necrotic and hibernating/stunned myocardium. Conclusion: Cardiac MRI is very useful in determining the morphology and extension of LV aneurysm. Cine sequences offer functional analysis, first pass perfusion and late enhancement allow differentiation of viable and necrotic areas and to determine the transmural extent of infarcted areas. 3D late-enhancement sequences, covering the entire left ventricle in three orientations, were indispensable for the determination and adaptation of areas of resection.

Cine MR, first pass perfusion and late enhancement in the evaluation of hypertrophic cardiomyopathies A. Kluge, T. Dill, C. Breidenbach, G.F. Bachmann; Bad Nauheim/DE Purpose: To assess the value of MRI in the diagnosis of hypertrophic cardiomyopathies. Methods: Thirteen patients with suspected hypertrophic cardiomyopathy were examined with a 1.5 T Magnetom Sonata MRI-Scanner (Siemens, Erlangen, Germany). Global cardiac function and wall motion were established with cine sequences, regional myocardial perfusion was examined by first pass multislice perfusion in rest and vitality was assessed by evaluation of late enhancement. Results: Of 13 patients examined, 12 had hypertrophic cardiomyopathy, 8 of them obstructive. No perfusion abnormalities could be detected at rest. 5 of the patients, all untreated, showed late enhancement in the hypertrophic areas of the basal septum, thus indicating patchy necrosis in this area. Conclusion: MRI is well suited for the examination and grading of hypertrophic cardiomyopathy. Although no patient underwent prior embolization for therapeutic septal infarction, 5 patients showed evidence of patchy myocardial necrosis in the basal septum indicating chronic ischemia at the same area normally targeted by embolization of the first septal branch of the LCA.

Lung C-0227 CT fluoroscopy-guided percutaneous fine needle biopsy in thoracic lesions E. Silit, Z. Pekkafali, E. Kizilkaya, C.C. Basekim, F.A. Karsli; Istanbul/TR Purpose: To evaluate the usefulness of computed tomographic fluoroscopy-guided transthoracic fine needle biopsy. Methods and materials: CT fluoroscopy-guided biopsies were performed in 46 patients with thoracic mass lesions. The cases were selected because of the small tumour size, tumour location and elderly noncompliant patients. The mean tumour size was 2.51 cm (range 1 -3.5 cm) and located at the periphery in 19 cases, central and hilar in 11 cases and subcostal or subscapular in 16 cases. Interrupted CT fluoroscopy technique was used with 50 -130 mA at 120 kV exposure parameters and slice thickness of 10 mm. Mean fluoroscopy time was 12.17 seconds and maximal procedure time was 18 minutes. Results: Adequate samples for cytopathological diagnosis were obtained in 43 cases at first and in three cases at second intervention. The diagnosis was malignant in 28 cases, benign in 14 cases and suspicious malignant in four cases. Pneumothorax and hemorrhage were observed in five cases ( %10.8) and none of them needed treatment. Because of the short procedure time and mostly one intervention, our complication rate was significantly low compared with literature findings. Conclusion: CT fluoroscopy-guided technique provides effective real-time needle biopsy in patients with small tumor size, tumor located near blood vessels and in non-compliant patients for diagnosing thoracic lesions. The procedure time and the complication rate were reduced by CT fluoroscopy.

3 He-MRI for diagnosis of obstructive lung disease: The European approach (PHIL) C. Bletz 1 , N. Weiler 1 , K. Katsaros 1 , E.J.R. van Beek 2 , K. Gast 1 , A. Hanke 1 , S. Ley 1 , J. Mortensen 3 , H.-U. Kauczor 1 ; 1 Mainz/DE, 2 Sheffield/GB, 3 Copenhagen/DK Purpose: 3 He-MRI is a promising tool for the detection of ventilation defects. Its clinical impact warrants further investigation. The aim of this study is to demonstrate the ability of 3 He-MRI to differentiate different forms and stages of chronic obstructive lung disease (with/without emphysema, different types of emphysema). Methods and materials: A multi-centre (Mainz, Sheffield, Copenhagen) clinical trial is supported by the European Commission under the framework V programme within the Polarized Helium for Imaging of the Lungs (PHIL) project. 150 Patients with the diagnosis of chronic bronchitis and/or emphysema are eligible for study entry. Patients with asthma will be excluded. The patients will undergo 3 He-MRI (static, dynamic and diffusion imaging), HRCT (morphology, densitometry), and pulmonary function tests (spirometry, body plethysmography). For comparison of the different modalities a comprehensive study book is designed. Results: The study book focuses on comparison concerning large airway abnormality (static ventilation defects, bronchial dilatation and wall thickening, FEV1), small airway abnormality (static ventilation defects, decreased alveolar inflow ratio, airtrapping, expiratory flows) and emphysematous destruction (apparent diffusion coefficient, mean lung density, emphysema index, residual volume, FEV1). Scores are assigned to extent and severity of the abnormalities detected. Comparability of scores is shown by retrospective assessment of 38 investigations including 3 He-MRI, CT and pulmonary function tests.

The study book of the European PHIL study allows comparison of the capabilities of 3 He-MRI, HRCT and pulmonary function tests for non-invasive discrimination of various forms of COPD. 

We reviewed CT studies of 37 clinically diagnosed COPD patients. Several parameters were studied in axial images and in tracheal lumen oriented reconstructed images. These were: sagittal and coronal diameters, anterior wall thickness, lumen area, tracheal index, SR/LR index (ratio of the short to the long radius) and morphology. Results: Our series show that saber-sheath trachea (tracheal index > 0.66) is more common than previously reported in COPD patients and is related to both a decrease in area and an increase in wall thickness. Tracheal deformity is not uniform along its length; in our experience it increased unexpectedly at the thoracic outlet. Axial images far above the aortic arch should be reformatted because they unreliably distort the true shape of the tracheal lumen. Additionally, the differences between the classic tracheal index and the newly developed SR/LR index are discussed. Conclusion: CT is a reliable tool for the study of tracheal shape and generates some new data that are useful in the evaluation and understanding of tracheal changes in COPD patients. 

We studied retrospectively 35 patients (22 males and 13 females) with histologically proven BAC diagnosed in our institution during the last 11 years. In all cases we studied the predominant radiologic findings and the evolution of the different radiologic features on chest X-ray and CT. We also evaluated the clinical history, tumor staging and treatment received. Results: In 26 Patients surgical treatment was not performed, the tumour being stage IIIA, IIIB or IV. The commonest radiologic findings defining progression were new nodular lesions (10 cases) followed by enlargement of previous lesions (9 cases) and confluence of nodular areas in a large consolidation (7 cases). Masses or focal areas of ground-glass attenuation changed into mixed areas with consolidation in 3 and 2 cases respectively. Loss of volume and decrease in size of areas of ground glass opacities were the commonest radiologic findings in patients with response to chemotherapy. We identified the transformation of areas of alveolar air-space occupation into areas of honeycombing in 5 patients, and air space consolidation and nodules into areas of ground glass attenuation in 3 cases. Conclusion: The usual findings of presentation of BAC can change into other described characteristic radiologic features during follow-up. Consideration of these changing features may aid in chemotherapeutic responses evaluation.

Nontraumatic postmortem computed tomographic (PMCT) findings of the lung S. Shiotani, M. Kono, N. Ohashi, K. Yamazaki, M. Wada, Y. Itai; Tsukuba/JP Purpose: We describe the non-traumatic postmortem computed tomographic (PMCT) findings of the lung. Materials and methods: A total of 126 non-traumatic patients who were referred to our institution in cardiopulmonary arrest on arrival state between November 19, 1992 and March 31, 2001 . Causes of death were 77 acute heart failure, 16 aortic dissection, 11 pneumonia, 19 other specified, 3 unspecified. Autopsy was performed in 16 patients. PMCT was performed for detection of the cause of death. PMCT scans were retrospectively reviewed and findings were categorised in dependent density (DD), diffuse bilateral ground glass attenuation (GGA), consolidation (CO). Results: PMCT findings and their frequency were as follows; acute heart failure (DD 70 %, GGA 66 %, CO 22 %), aortic dissection (63, 31, 6 %), pneumonia (27, 64, 100 %), other specified (63, 26, 16 %), unspecified (33, 0, 0 %), total (63, 54, 26 %). Diffuse bilateral ground grass attenuation was found in AHF cases more frequently than other causes of death (p < 0.05). There were no significant difference between frequency of dependent density and consolidation between individual and total cause of death. Autopsy showed that ground glass attenuation in AHF cases corresponded to pulmonary edema. Pulmonary edema also occurred in AD (aortic regurgitation) and subarachnoid hemorrhage (neurogenic edema). Conclusion: When PMCT of the lung show no other shadows than dependent density, we need to analyze them as significant. In suspected cases of acute heart failure, bilateral diffuse ground glass density could be indirect evidence.

Chest spiral CT and high-order interpolators: Resolution and artifacts J.M. García Santos, J. Cejudo, R. Rodríguez Mondéjar, S.M. Torres del Río, A. Blanco; Murcia/ES Purpose: To report the advantages and disadvantages of spiral CT high-order interpolators and how they are produced. Material and methods: The lung and mediastinal images obtained from thoracic CT examinations in 20 patients were retrospectively reviewed. They had been previously analysed in order to assess the resolution induced by a high order interpolator. The study was now focused on the evaluation of the visible spurious differences between images reconstructed with standard and high-order interpolators. In order to demonstrate the nature of these artifacts we studied the effects of the standard and high-order interpolators on the CT images of two different phantoms, one with straight edges and the other with curved surfaces. The slice sensitivity profiles of both images were also evaluated with both phantoms. Results: Two artifacts were visualised with a high-order interpolator: (1) superimposed dense images on the mediastinal edges, and (2) peripheral, crescent, hypodense areas under the thoracic wall, simulating a pneumothorax. The artifacts varied their intensity both depending on patient constitution, and also between slice position in the same patient. The curved-surfaced phantom reproduced the thoracic artifacts, which didn't appear with the other. The high-order interpolator in 14 patients also increased images' noise level. The higher resolution of the high-order interpolator images was previously demonstrated in other work.

The high-order interpolator increases the image's noise level although improving resolution. The way in which the interpolator reconstructs an image from a curved-surfaced object is responsible for the artifacts visualised.

Pitfalls in chest radiograph interpretation C. Hill, S.K. Morcos; Sheffield/GB Purpose: To present important principles in the interpretation of the chest radiograph. Materials and methods: A pictorial review. Results: Important rules for the interpretation of the chest radiograph are presented. The importance of assessing factors that influence the appearance of the chest radiograph, and may simulate or mask pathology, is highlighted. These include exposure factors, patient position (AP, erect, supine, degree of rotation or lordosis) and phase of respiration. The need to review the criteria of a satisfactory examination (correct labelling, lungs completely visualised, hair and clothing artefacts avoided) is emphasized.

Interpretation of the chest radiograph should begin with evaluation of the technical factors that may influence the appearance and quality of the image. Following this, the main structures (heart, lungs, mediastinum, chest wall) are assessed. Analysis of the review areas (apices, behind the heart, below the hemidiaphragms) completes the process. Conventional chest radiographs are the mainstay of thoracic imaging. It is essential to recognise the diagnostic limitations of the chest radiograph due to technical factors.

Experimental platform for imaging studies on porcine lung explants J. Biederer, M. Heller; Kiel/DE Purpose: Development of a MRI-compatible artificial thorax for experimental studies on porcine heart-lung preparations with magnetic resonance and other imaging modalities.

The double-walled container with the inside shape of a porcine thorax holds a fresh heart-lung preparation. Access to the lung and it's vessels is given through a tracheal tube and catheters in pulmonary artery and ascending aorta. The lung inflates via the tracheal tube, when the artificial thorax cavity is constantly evacuated at 20 -30 hPa. A flexible membrane replaces the genuine diaphragm and allows for the simulation of abdominal breathing. All materials are antimagnetic to avoid susceptibility artifacts. The double walls can be filled with saline to simulate MR-signal or radiation-absorbing qualities of a chest wall. Fresh porcine heart-lung preparations are acquired from a local butcher. Results: The model was successfully tested for magnetic resonance imaging as well as conventional X-ray, angiography and CT. A single heart-lung preparation can be used for up to 9 hours. Gases or aerosols can be easily applied via trachea and bronchi of the inflated lung. A low flow circulation within the lung vessels is achieved with an external pump. Access to the vessels permits development and training of interventional procedures. 

A volumetric interpolated 3D-gradient echo sequence for MRI of the lung: Evaluation in healthy volunteers and first experience in patients J. Biederer 1 , J. Graessner 2 , C. Liess 1 , M. Both 1 , M. Heller 1 ; 1 Kiel/DE, 2 Hamburg/DE Purpose: To evaluate the feasibility of a magnetic resonance imaging protocol for the lung using a volumetric interpolated 3D-gradient echo sequence (3D-GRE). Methods and materials: A T1-weighted 3D-GRE sequence was used for volumetric interpolated breath-hold examinations ("VIBE") of the lung in twelve healthy volunteers and twelve selected patients with malignant lung disease (TR/TE 4.5/ 1.9 ms, flip angle 12°, matrix 502 × 512 (interpolated)). Three coronal 80 mm slabs (16 partitions, 2.5 mm slices) were added to 3D data sets for multi-planar reformations. No contrast material was applied. Artifacts and resolution of vessel and airway structures in each lung segment of the healthy volunteers were evaluated by two observers (228 lung segments). MRI findings were compared to CT findings. Results: The protocol provided excellent images of vascular and tracheo-bronchial structures with very moderate pulsation artifacts. 224/228 lung segments were imaged with "good" (146/228) or "sufficient" quality (78/228). Bright flow signal identified segmental and sub-segmental vessels (5 th order) without administration of contrast material. Walls of segmental bronchi (3 rd order) were delineated in all parts of the lung. The patient studies confirmed a high image quality. In 11/12 patients the diagnosis from separate reading of the 3D-GRE series did not differ from CT diagnosis. Conclusion: The 3D-GRE (VIBE) sequence provides high spatial resolution, excellent visualization of lung anatomy, short acquisition times and a low rate of artifacts without respiratory triggering. We expect, that 3D-GRE sequences with these qualities will replace existing 2D-GRE strategies for MRI of the lung. Purpose: Definition of a fast lung MRI protocol for follow up in patients with cystic fibrosis using T1-and T2-weighted breath-hold sequences at 1.5 T. Methods and materials: Ten patients with different stages of cystic fibrosis of the lung were assessed with a volumetric interpolated 3D-GRE-(TR/TE 4.5/1.9 ms, matrix 502 × 512, 2.5 mm slices) and a fast breath-hold T2-weighted HASTE-sequence (TR/TE 2000/43 ms, Matrix 192 × 256, 8 mm slices) in coronal orientation. The number of slices per acquisition was adapted individually respecting the tolerable breath-hold time frame (10 -20 s). The first examination in each patient included a respiration-triggered T2-TSE-Sequence (TR/TE 3000 -6000/120 ms, Matrix 270 × 512, 6 mm slices, axial orientation). MRI findings were compared with chest X-ray and HRCT scans, if available. Results: MRI findings correlated well with X-ray, CT and the clinical course. Bronchiectases and infiltrates were clearly identified. Retention of mucus and fresh peribronchial infiltration showed high signal on T2-and intermediate signal on T1weighted images. Pulmonary hemorrhage and aspergillosis were detected. The 3D-GRE sequence provided a higher spatial resolution, but T2-HASTE was robust to cardiac pulsation artefacts and more sensitive to infiltrates. T2-weighted images of high detail resolution were provided by respiration-triggered T2-TSE series, but imaging time increased from 10 -15 min to 25 min, if respiration-triggered series were included. Conclusion: The fast MRI protocol provides valuable diagnostic information in patients with cystic fibrosis and may replace chest X-ray studies for follow-up without radiation exposure. Respiration-triggered series may be added to acquire T2weighted images of high detail resolution comparable to CT, if necessary.

Infectious pulmonary complications in liver transplant recipients: Radiological appearance M. Cossu, P. Boraschi, E. Neri, G. Campori, P. Rondine, F. Falaschi; Pisa/IT Purpose: The aim of the exhibit is to report the radiological patterns of infectious pulmonary complications in liver transplanted patients.

The study group included 163 subjects previously submitted to orthotopic liver transplantation during a 2 year period. All chest X-ray (n = 163) and CT studies (n = 68) were retrospectively reviewed by two observers in conference and correlated with clinical, microbiological, serological and histopathological findings. Patients with infectious pulmonary complications were classified into three groups according to their prevalent radiological pattern: (a) lobar or segmental, unique or multiple consolidation; (b) nodules with or without cavitation; (c) diffuse infiltrate. Results: Pneumonia were diagnosed in 25/163 patients (15 %), including 15 proven bacterial (2 in association with mycobacterium), seven viral (3 in association with bacterial) and four fungal cases. Pulmonary consolidation was the most frequent pattern, but sensitivity and specificity were relatively low (80 % and 60 %, respectively for CT). Nodules were always present in case of mycotic infection (NPV 100 % for CT). Diffuse infiltrate was always associated with viral infection (PPV 100 %), but sensitivity was low (40 % for CT studies). The distribution of X-ray/CT patterns was not statistically significant (p > 0.05). Conclusion: In patients with liver transplantation the radiological patterns of infectious pulmonary complications are often not specific. A good diagnostic confidence can be obtained only in patients with fungal infection.

Chronic obstructive pulmonary disease: Measurement of airway lumen and wall areas from high-resolution computed tomographic data using a Laplacian of Gaussian algorithm V. Pérot jr., P. Berger sr., P. Desbarat jr., H. Begueret sr., M. Montaudon sr., F. Laurent sr.; Pessac/FR Purpose: Validation of software to measure airway lumen and wall areas of bronchi on HRCT data and comparison between patients suffering from COPD and a control group. Material and methods: An algorithm LoG (Laplacian of Gaussian) was used to conceive a software for extracting bronchi geometrical parameters from HRCT data. A validation was performed using a phantom and animal lungs of subjects characterized by clinical and PFT findings fixed in inflation. Using Spirometric gating, HRCT was performed in 3 groups characterized by PFT results, a group of severe COPD, a group of moderate COPD, and a control group. Bronchi airway lumen and wall areas were measured on bronchi using the dedicated software. Results: Correlations between airway lumen and wall areas of bronchi obtained by the software and those obtained from the phantom or measured by visual method from the animal lung or from the phantom were excellent (Pearson's coefficients included between 0.993 and 0.996, and 0.859 and 0.986 respectively) as well as inter and intra observer reproducibility (0.998 < r < 0.999) [p < 0.05]. A significant difference of bronchi wall areas measurements was found between the 3 groups of subjects (p < 0.05). Conclusion: Bronchi wall areas are related to the severity of COPD and can be measured on HRCT images using a dedicated software.

Comparative functional evaluation of airways and lung parenchyma with high-resolution and dynamic CT J.R. Ederle, C.P. Heussel, J. Hast, B. Fischer, S. Ley, M. Thelen, H.-U. Kauczor; Mainz/DE Purpose: To evaluate correlation between changes in area and/or diameter of central airways and lung area or mean lung density to better understand the dependencies between airways and parenchyma on CT. Materials and methods: Static parameters using HRCT in inspiration and expiration of 156 patients were evaluated retrospectively. Cross-sectional area of the trachea (CSAt) was correlated with mean lung density (MLD), cross-sectional area of the lung (CSAl) and diameter of the main bronchi. 31 patients with tracheal diseases underwent cine-CT. CSAt was correlated with MLD and CSAl. Additionally, MLD was correlated with CSAl for different thresholds representing airways (− 1024 to −910 HU), ventilated lung parenchyma (−910 to −700 HU) and connective tissue (−700 to −200 HU). Results: The changes in CSAt and CSAl are similar (18 %). CSAt correlated moderately with the diameter of the main bronchi (r = 0.46) and CSAl (r = 0.41). Especially for patients with normal or obstructive lung function a correlation between CSAt and both MLD and CSAl was found, r = −0.49 and 0.60 respectively. In the dynamic study a correlation between MLD and CSAl was found (r = −0.57). Conclusion: Static imaging shows dependencies between central and peripheral flow and pressure patterns in normals and in obstructive lung disease. Dynamic measurements reinforce these results in cases without severe tracheal patholo-

Chest gies. This important information on the functional behaviour of airways and parenchyma will be used to better understand the delivery of inhaled therapies and improve early diagnosis of disease.

Comparative evaluation of portable chest röntgenography (PCR) to chest computed tomography (CCT) in intensive care unit (ICU) patients T. Geroukis, M. Sidiropoulou, K. Manolokaki, A. Manolokaki, V. Kalpakidis, P. Palladas; Thessaloniki/GR Purpose: To compare the findings of portable chest roentgenography in ICU patients to those of CCT and to determine the degree that CCT alters clinical management. Materials and methods: 42 patients (age range 15 -74 years) receiving intensive care during the last year, underwent 45 CCT examinations. We reviewed the clinical and radiographic records for demographic data, etiology of admission to the ICU, PCR findings, radiologic or clinical indication for CCT, findings of CCT and evaluated whether additional information obtained from CCT altered clinical patient management. Results: Three main clinical indications accounted for 32 (71.1 %) of all CCT exams: evaluation of respiratory failure (31.1 %), fever (20 %) and chest trauma (20 %). 352 total findings were documented in our study group of which PCR demonstrated 133 findings and CCT showed 219 (62.3 % of total findings). 117 of the 133 PCR findings (88 %) were confirmed at CCT. CCT provided 91 findings (41.5 % of total CCT findings) which were unsuspected on prior PCR. These important new findings were mainly: pleural (53.8 %), pulmonary (28.5 %) and chest wall (8.8 %). 23 (25.2 %) of the new CCT findings were clinically significant. Most of these were: lung abscesses, large pleural effusions and unsuspected pneumonia. CCT findings led to direct changes in clinical management in 19 examinations (42.2 %). Conclusion: PCR provides sufficient information in the majority of ICU patients. CCT adds to the diagnostic accuracy and influences the clinical management of ICU patients by: ruling out particular clinical concerns, affirming diagnoses suspected on prior radiographic findings and demonstrating new findings. with Churg-Strauss syndrome, 7 with collagen disease). These CT images were retrospectively reviewed by two chest radiologists with respect to the pattern and distribution of the lesions. Results: The most common CT findings were areas with ground-glass attenuation (82 %), followed by centrilobular nodules (59 %), thickening of bronchovascular bundles (43 %), interlobular septal thickening (41 %), nodules (> 1 cm) (39 %), consolidation (29 %), and honey combing (27 %). These pulmonary abnormalities were most commonly seen in the peripheral lung parenchyma (77 %). Conclusion: Pulmonary lesions in patients with MPO-ANCA can manifest various CT patterns, but the most common CT findings are ground-glass attenuation and centrilobular nodules, which are most commonly seen at the peripheral lung parenchyma.

Evaluation of dynamic MR imaging for differentiating peripheral primary pulmonary adenocarcinomas from focal organizing pneumonias K. Fujimoto, J. Sadohara, H. Terasaki, R. Kono, N. Hayabuchi, A. Hayashi, T. Rikimaru, S. Kato; Kurume/JP Purpose: To evaluate the usefulness of Gd-DTPA-enhanced dynamic MR imaging in differentiating peripheral, primary pulmonary adenocarcinomas from focal organizing pneumonias (FOPs). Methods and materials: Dynamic MR images were performed in 81 cases with pathologically established pulmonary adenocarcinoma and 29 cases with FOP. Dynamic MR imaging was obtained prior to administering contrast medium and seven more images were acquired every minute after bolus injection of Gd-DTPA. Time-enhancement ratio (TER) curves were classified into three types. Type A had an early peak (£ 4 minutes), type B had a delayed peak (> 4 minutes), and type C was a gradually increasing type. The type of TER, the maximum enhancement ratio (MER), time at MER (Tmax), and the slope of the TER curve (Slope) were compared between adenocarcinomas and FOPs. Results: 65 of 81 patients with adenocarcinoma (80 %) and 20 of 29 patients with FOP (69 %) were classified as type A. The remaining 16 adenocarcinoma cases and 9 FOP cases were classified as type B or C. There was no statistical difference of the MER or the Tmax of the TER curve between the adenocarcinoma and FOP groups. There was a statistically significant difference, however, in the Slope between adenocarcinomas and FOPs (P < 0.005). Conclusion: These results suggest that dynamic MR imaging, especially in the Slope of the TER curve, is useful for differentiating peripheral, primary pulmonary adenocarcinomas from FOPs.

Monitoring the monitors: Tubes and lines on chest radiographymalpositions and complications P. Wunderbaldinger, J. Sailer, A.A. Bankier; Vienna/AT Chest radiography is essential to evaluate the placement and position of tubes and lines, such as central venous and arterial catheters, endotracheal and nasogastric tubes, thorax drains, cardiac pacemakers and defibrillators. This presentation aims to illustrate and discuss the correct position of tubes and lines on chest radiographs, as well as potential malposition and subsequent complications.

Lung findings on high resolution computed tomography in early ankylosing spondylitis: Correlation with pulmonary function tests A. Kiris, E. Kocakoc, S. Ozgocmen, O. Ardicoglu, E. Ogur; Elazig/TR Purpose: Ankylosing spondylitis (AS) is a chronic inflammatory disease affecting the axial skeleton and known to cause pulmonary disease. The aim of this study was to investigate the pulmonary high resolution computed tomography (HRCT) findings of patients with early AS. The relationship between pulmonary function tests (PFT) and HRCT findings were also determined. Methods and materials: 26 patients (mean age 30.5 ± 7.4 and disease duration 7.0 ± 2.6) who met modified New York criteria for AS were included into the study. Patients with a disease duration more than 10 years or had other pulmonary diseases were excluded. All patients underwent plain chest radiography (posteroanterior and lateral views), thoracic HRCT, and PFT. Results: All of the chest radiographs were normal and HRCT revealed abnormalities in 17 patients. The most common abnormalities seen on HRCT were mosaic oligemia (7/26), subpleural nodule (6/26) and parenchymal bands (6/26). Ten patients had abnormal PFT and all were restrictive type of involvement. Eight of these 10 patients had abnormal HRCT and the rest 2 patients had normal HRCT. On the other hand 9 patients with normal PFT had abnormalities on HRCT. Conclusion: Patients with early AS frequently have abnormalities on HRCT even though have normal PFT.

Retrospective ECG-gated high resolution CT of the lung Z. Pan 1 , H. Zhang 1 , H. Zhang 1 , H. Ling 1 , W. Fang 1 , Q. Song 1 , Y. Shen 2 , J. Yi 1 , K. Chen 1 ; 1 Shanghai/CN, 2 Tokyo/JP Purpose: To investigate improvement of lung HRCT image quality by reduction of cardiac motion artifact with ECG gated MDCT. Method/materials: 50 patients were examined on a MDCT scanner (GE LightSpeed QX/I, 0.8 s rotation speed) using HRCT and retrospectively ECG gated cine scan modes (Two rotation scan with time overlapping technique for one plane, 10 -15 planes were used for one case, 10 mm scan interval, 1 × 1.25 mm collimator). Based on the ECG information and using cine overlapping technique, diastolic phase with cardiac motion artifact free was selected. We have assessed improvement of image quality of lung HRCT by comparison of result with ECG gated mode and without ECG gated mode. Results: Scores of 600 images were statistically analyzed and the results indicated that the incidence of artifacts caused by cardiac motion was less obvious in ECG-gated HRCT compared with routine HRCT (P < 0.001) with presence of blurred cardiac border (P < 0.05), double line artifacts (P < 0.05) and star like artifacts (P < 0.01). ECG gating helped significantly reduce artifacts caused by cardiac motion (distortion of pulmonary vessels, double images, or blurring of the cardiac border) than normal non-ECG gated mode. Conclusions: ECG gating improves image quality of lung HRCT scans by reducing cardiac motion artifacts that may mimic disease. Based on a review of a large number of pathologically proven pleural disorders, we discuss the CT and MR findings of a variety of benign and malignant pleural lesions other than malignant mesothelioma. Benign lesions include among others fibrous tumors, lymphangiomatosis, hemangiomatosis, pleural plaques, and splenosis. Malignant pleural diseases include invasive thymoma, metastases, epithelioid hemangioendothelioma, and lymphoma. Correlation with gross or microscopic pathology is done in selected cases.

The simple things we have to know: Expected anatomical changes in the postoperative chest G.I. Kirova, G. Kalaydjiev, M. Shindov, P. Tconev, H. Tcenkov, G. Hadjidekov; Sofia/BG The operation is the only radical therapy for patients with bronchial carcinoma. Based on the staging and the local spread of the tumor several different operative techniques are used. The detection of expected anatomical postoperative changes on chest radiography and CT is a vital skill required of chest radiologist. All these changes frequently cause diagnostic uncertainty and the knowledge of their usual appearance is of crucial value. To delineate a potential pathological process one must first have a good understanding of the anatomical relationship and postoperative spatial changes in the thorax. The exhibit illustrates the spectrum of postoperative lung abnormalities in case of right and left pulmonectomy, right upper, middle and lower lobe lobectomy, left upper and lower lobectomy as well as in right bilobectomies. Our discussion demonstrates a logical way of explanation of the different postoperative findings within the thoracic cavity. We also discuss the CT features that can be used to distinguish one type of operation from other -the changes in the position of the remaining pulmonary parenchyma, the course and completeness of oblique and horizontal fissures, the presentation of the bronchial stump and the reorientation of the remaining bronchial and vascular structures.

Pulmonary hypertension: Findings of chest CT and spiral CT angiography (CTA) of pulmonary arteries C. Samara, E. Kamarioti, C. Trompoukis, Z. Nikolakopoulou, K. Liberopoulos, N. Courcoutsakis, S. Kavadias, G. Zois; Athens/GR Purpose: To estimate the value of spiral CT angiography of pulmonary arteries in patients with pulmonary hypertension. Materials and methods: 29 patients, aged 20 -81 years, who presented with pulmonary hypertension due to pulmonary emboli (9/29), acquired heart valve disease (14/29), primary pulmonary hypertension (5/29) and sarcoma of the heart (1/29) were included in this retrospective study. The diagnosis of pulmonary hypertension was confirmed by transthoracic echocardiography. All patients underwent chest CT and CTA of pulmonary arteries (150 ml contrast medium, flow rate: 3 ml/s, scan delay: 20 s, slice thickness: 3 mm, table feed: 3 mm, reconstruction index 1 mm). Imaging findings were evaluated from two radiologists. Results: CTA was abnormal in all patients. Findings included: large peripheral and central filling defects in the pulmonary arteries (9/29), changes in caliber and mural vascular irregularities (11/29), dilatation of main and segmental-subsegmental pulmonary arteries (13/29), patchy areas of high and low attenuation-mosaic pattern of perfusion in lung parenchyma (16/29), pulmonary infarctions (8/29), pleural effusion (10/29), filling defect in the left atrium (1/29) and signs of right heart failure such as dilatation of right ventricle, right atrium, vena cava and widened main and central pulmonary artery (19/29). Conclusion: Although chest CT and CTA cannot measure the pulmonary arterial pressure, can depict the morphological changes due to pulmonary hypertension. CTA is a non-invasive imaging tool and may be used for chronic thromboembolic pulmonary hypertension screening as well as others cause of pulmonary hypertension. Using spiral CTA in combination with echocardiography will provide the best evaluation and treatment for patients with pulmonary hypertension.

Pulmonary tuberculosis in idiopathic pulmonary fibrosis M.J. Chung, J.-G. Im, J.M. Goo, S.H. Paik, Y.K. Yoon; Seoul/KR Purpose: Patients with idiopathic pulmonary fibrosis (IPF) are known to be at increased risk for pulmonary tuberculosis (TB). However, detection of pulmonary TB may be difficult due to underlying fibrosis. The aim of this study is to describe the radiological and clinical findings of pulmonary tuberculosis in patients with IPF. Materials and methods: We reviewed 143 consecutive patients in whom IPF was diagnosed by histologic or radio-clinical criteria defined by joint statement of ATS and ERS. Among them, nine patients were histologically (n = 2) or bacteriologically (n = 7) confirmed to have active pulmonary TB (annual incidence 0.9 %, more than five times than the incidence of general population in Korea). We analyzed the location and patterns of pulmonary TB on CT scan. We also reviewed the clinical findings of patients. Results: Four patients underwent steroid pulse therapy for more than three month at the time when active TB occur, and the other five were not exposed to any immunosuppresive therapy before TB occur. Most common CT findings were subpleural nodules (n = 5; mean diameter, 2.1 cm) and lobar or segmental consolidation (n = 4). Transthoracic needle biopsy was performed in two patients to differentiate from the lung cancer associated with IPF. In two cases, there were large cavities in the area of consolidation. Conclusion: The incidence of TB in patients with IPF was more than five times higher than that of general population. Atypical manifestation of pulmonary TB is common in patients with IPF, which may mimic lung cancer or bacterial pneumonia.

Functional assessment of the inspiratory pump using MRI in normal and various pathologic conditions P. Cluzel, T. Similowski, A. Constantinescu, S. Basso-Ricci, J.-P. Derenne, M. Zelter, P.A. Grenier; Paris/FR Purpose: The correct functioning of the inspiratory pump is of paramount importance to the physiology of breathing and the pathophysiology of many diseases. The aim of this exhibits is to demonstrate the potential role of MRI of the thorax as a tool for structure-function evaluation of chest-wall mechanics. Patients and methods: Healthy volunteers, patients with emphysema before and after lung volume reduction surgery and patients with diaphragmatic paralysis participated in the study. 3D reconstruction of the inspiratory pump using MRI have been developed allowing collection of geometric data (lengths, surfaces and volumes of the rib cage and diaphragm) at different lung volumes, total lung capacity, functional residual capacity and residual volume. Those later volumes were correlated with the corresponding spirometric data and with the twitch transdiaphragmatic (Pdi), oesophageal (Pes) and gastric pressures, determined by bilateral supramaximal electrical stimulation of the phrenic nerve in the neck. Results: Good agreement was found between the corresponding spirometric and MRI values of lung volumes. Pdi and Pes decreased with decreasing areas of the diaphragm with lung volumes, emphasizing the major role of the area of the diaphragm zone of apposition in the diaphragm ability to produce inspiratory pressure. A two-compartment model of the inspiratory pump, with model parameters identification derived from measurements obtained by MRI have been developed. Conclusion: MRI of the thorax with 3D reconstruction should improve our ability to evaluate the respiratory pump in clinical and research investigations. Modeling the inspiratory pump enable access to internal parameters of the chest-wall mechanics.

A comprehensive CT study in adult respiratory distress syndrome P. Cluzel, L. Puybasset, J.-J. Rouby, F. Prêteux, P.A. Grenier; Paris/FR Purpose: To demonstrate the role of CT for describing regional lung anatomy and physiology in patients with adult respiratory distress syndrome (ARDS). Patients and methods: 71 patients fulfilling the American-European consensus conference definition of ARDS were studied by computed tomography (CT). CT images were obtained at functional residual capacity (FRC) and different levels of positive end-expiratory pressure (PEEP). A visual interpretation of the CT images and a regional quantification of the volume of gas and tissue by a proprietary software (Lungview®) were used. Respiratory parameters (shunt fraction, pressure-volume curves …) and mortality were studied. Results: The distribution of attenuation allowed the identification of three groups of patients; lobar in Group 1, diffuse in group 2 and patchy in group 3. In all three groups there was an excess of volume of tissue (compare to normals). There was a significant decrease in the FRC gas volume in all groups, with the greatest loss C A B D E F 388 Chest in the lower lobes. All patients had less normally aerated lung and more poorly aerated lung. Differences were detected in the response to PEEP among the three groups, with greatest decrement in shunt and improvement in PaO2 occurring in patients with diffuse opacities. The role of the heart in the loss of aeration of the left lower lobe was addressed. Conclusion: CT study with analytic technique holds the promise of providing a better understanding of this heterogeneous disease. Identification of homogeneous subgroups would be of great value in testing therapeutic strategies.

Comparison of multislice CT and MR in the preoperative assessment of superior sulcus tumors: Preliminary experience S. Lenoir, N. Bouzar, M. Zins, C. Strauss, D. Grunenwald, R. Palau; Paris/FR Purpose: To compare the respective value of multislice CT and MR imaging in the evaluation of locoregional extension in the preoperative staging of superior sulcus tumors. Material and methods: 10 superior sulcus tumors were studied by both multislice CT and MR. CT acquisitions were performed after contrast medium administration with a nominal thickness of 1.25 mm followed by sagittal and coronal oblique reformations. MR studies included T2, T1-weighted SE sequences using a phasedarray coil, a FOV of 24 cm, a 4 mm-slice thickness in axial, sagittal and coronal oblique imaging. CT and MR scans were independently assessed by 2 radiologists, and results were compared with surgical data. Results: The quality of reformations was optimal in all CT studies and in n = 8 MR examinations. Rib destruction and vertebral cortical bone erosion was better assessed by CT (n = 4). Spinal foramen (n = 2) and bone marrow (n = 1) involvement were better evaluated by MRI due to its better contrast resolution. The relationships of the tumor to the subclavian artery, brachial plexus, chest wall and epidural space were equally assessed by both techniques. Conclusion: Multislice CT is at least as good as MR in the preoperative assessment of the extension of superior sulcus tumors.

Solitary pulmonary nodules: Effect of section thickness on diagnosis with high resolution CT S. Iwano 1 , N. Makino 2 , M. Ikeda 1 , S. Itoh 1 , M. Tadokoro 2 , H. Satake 1 , T. Ishigaki 1 ; 1 Nagoya/JP, 2 Toyota/JP Purpose: To determine a suitable section thickness to differentiate malignant from benign solitary pulmonary nodules (SPN) on high resolution CT images. Method and materials: A total of 104 SPNs which were pathologically or clinically proven were included in this study. Forty-nine lesions were malignant (9 -35 mm in diameter, mean 20.1 mm) and 55 lesions were benign (8 -35 mm in diameter, mean 19.0 mm). In each case, four radiologists indicated their confidence level for the malignant or benign SPN on the CT images presented in 1 mm, 3 mm, 5 mm, and 10 mm slice thickness. Receiver operating characteristic (ROC) analysis was used to analyze the reading session. The area under the ROC curve (Az) measured the observer's ability to differentiate malignant from benign SPNs.

The Az values decreased from 0.831 for the 1 mm slice thickness to 0.761 for the 10 mm slice thickness. In the group of 55 nodules smaller than 20 mm in diameter, all observers showed that the Az values for the 1 mm slice thickness were higher than for the 3 mm slice thickness.

The observer performance of the thin slice CT images in differentiating malignant from benign SPNs is better than the 10 mm slice CT images. Scanning with the thinnest possible thickness is essential for small nodules.

Ultra-low-dose thin-section spiral CT for lung cancer mass screening using a multidetector row CT Y. Maruyama, H. Yamamoto, H. Yamaguchi, M. Koyama, S. Kubori; Komoro/JP Purpose: To reduce work-up rates and increase accuracy for small nodules in low-dose spiral CT lung cancer mass screening. Materials and methods: In total, 957 patients (285 women and 672 men; mean age, 56.7; 561 smokers and 396 non-smokers) were screened by MDCT (LightSpeed QX/i, GE Medical Systems) (120 kVp; 10 mAs; detector width, 2.5 mm; couchtop speed, 7.5 mm, 0.8 s/rotation; helical pitch, 3). Average scanning time from base to apex was 26 s during a single breath-hold. A RadWorks (GE) was employed for image interpretation using a high-definition monitor. Approximately 100 images were evaluated with window widths/levels of 1000/−700 and 300/20 HU.

Results: Cancer was suspected in 44 patients (4.6 %) (7 probable, 37 possible). Lung cancer or AAH was suspected in 15 patients by workup CT, and 10 underwent surgery (7 well-differentiated adenocarcinomas and 3 AAH). Probable or possible cancers were identified in 9 patients by CT screening. One unidentified probable non-cancer was adenocarcinoma. Conclusion: This method allows small nodules to be evaluated based on their location in secondary lobules, pleural relationships, and margins. Cancer/non-cancer differentiation is easier than in conventional low-dose screening CT (singledetector spiral CT; slice thickness, 10 mm; helical pitch, 2). The work-up rate following low-dose spiral CT mass screening is reported to be 8 % -25 %, but was 4.6 % in our study, with sensitivity and specificity of workup CT for identified masses at 92 % and 83 %, respectively. Some active inflammatory lesions were confused with lung cancers, requiring special attention.

Pictorial essay: Therapy and prevention of pneumothorax during CTguided percutaneous cutting biopsy of the lung M.C. Freund 1 , M. Hackl 2 , J. Bodner 1 , T. Schmid 1 , W.R. Jaschke 1 ; 1 Innsbruck/AT, 2 Natters/AT Purpose: Pneumothorax is the most common complication of percutaneous lung biopsy. Therefore radiologist has to be familiar with chest tube therapy utilizing various large and small bore catheters. However several techniques can prevent a pneumothorax e.g. blood-patch technique or injection of either cyanoacrylat glue (Histoacryl®) mixed with oily contrast material (Lipiodol®) or injection of a commercially available 2-component fibrin glue (Tissucol® Duo Quick) in the puncture tract during the withdrawal of the coaxial sheath at the end of the examination. Methods and materials: In total 160 consecutive adult patients underwent CTguided percutaneous biopsy for histological evaluation of an intrapulmonary lesion utilizing a 17 -18 G coaxial cutting biopsy system. All lesions were surrounded by aerated lung parenchyma. Patients were assigned to undergo biopsy either without (group I) or with different preventive therapies: autologous blood clot (group II), cyanoacrylat glue mixed with oily contrast material (group III) or 2-component fibrin glue (group III). All patients were observed after biopsy. Typical clinical examples as well as procedure techniques will be displayed Results: The rate of CT-proven pneumothorax resp. for chest tube insertion in group I was 40 % resp. 4 %, group II 30 % resp. 4 % and group III and IV 10 -15 % resp. 1 -2 %. Conclusion: The injection of a more permanent occlusion of the puncture tract with either cyanoacrylat glue mixed with oily contrast material or 2-component fibrin glue during withdrawal of the coaxial sheath significantly reduces the incidence for pneumothorax as well as the rate for chest tube insertion.

Sectional anatomy of the chest: Interactive teaching atlas F. Lallouet 1 , E. de Kerviler 1 , J.F. Sissakian 2 , S. de Géry 1 , N. Benchaïb 1 , J. Frija 1 ; 1 Paris/FR, 2 Torcy/FR Purpose: Our purpose was to develop a radiological atlas of sectional anatomy of the chest. Methods and materials: Normal axial CT slices of the thorax have been selected and directly transferred from our radiology workstations to a PC. Then, images and text have been incorporated into ToolBook®, a multimedia authoring software for Microsoft Windows. Results: In this computer-aided atlas, the user is able to select an anatomical level. Each screen is fully interactive, so that the user can move the cursor onto an anatomical structure and highlight its legend, or click onto the legend to highlight the anatomical structure. Conclusion: Our learning objectives are: to learn the normal sectional anatomy of the chest and to show possibilities of computer teaching program in chest anatomy.

Can you make a story from a single chest radiograph? K. Hayashi, K. Ashizawa, K. Nagaoki, A. Aziz, H. Hayashi; Nagasaki/JP Purpose: With the development of a number of sophisticated new modalities of imaging the importance of chest radiograph is often forgotten. The purpose of this exhibit is to demonstrate the utility of chest radiograph in describing the dynamics of chest disease in an interactive way. Methods and materials: We selected 10 examples from our collection, in which one can make a story of the patient by just looking at the chest radiograph (sometimes with a brief history). Results: Ten cases will be presented in a question and answer style so that the observer can tell if he or she can make a good story from each case. The presentation would be in a familiar walk through web browser form with clickable hyperlinks. Conclusion: It is important to observe chest radiograph carefully. Sometimes one should use imagination to make a story. The chest radiograph finding may be very subtle but it may turn out to be a clue in the diagnosis of important diseases.

A new mass screening project for lung cancer with mobile spiral computed tomography (CT) and computed radiography (CR) in Ehime district, Japan T. Murakami; Ehime/JP Purpose: To improve the detection rate of lung cancer in mass screening, we have introduced low-dose CT and CR with temporal subtraction technique into a population-based annual mass screening for lung cancer supported by the Ehime Anti-Lung Cancer Organization (Ehime ALCO). Method and materials: From December 1999 to February 2001, 3868 and 12618 individuals aged over 40 years participated in the screening program with mobile low-dose CT and that with mobile CR, respectively. CT and CR were separately interpreted by two readers from Ehime ALCO. When the diagnoses were different between two readers, final diagnosis was obtained by consensus. CR was interpreted without subtraction technique in the first year. When lung abnormalities were suspicious for lung cancer, diagnostic CT scan of the chest with high-resolution imaging was performed at the referred hospitals for management purpose. Results: Primary lung cancer was detected by CT in 17 patients and by CR in 8 patients. The detection rate was 0.44 % and 0.06 %, respectively. All but one was adenocarcinoma. Male/female ratio of the patients was 7/10 in CT group and 2/6 in CR group. Number of stage IA cancer was 16 (95 %) and 4 (50 %), the mean diameter of tumour was 1.7 cm (range 0.5 -3.5) and 2.5 cm (range 1.5 -5.5), respectively. Conclusion: The mass screening with mobile CT increased the detection rate of primary lung cancer as had been previously reported. We need further test to evaluate its ability with subtraction technique in the second year.

Invasive pulmonary aspergillosis: Findings on conventional and highresolution computed tomography Ç. Atasoy, S. Fitoz, E. Düsünceli, C. Yagci, S. Akyar; Ankara/TR Purpose: To investigate the findings of invasive pulmonary aspergillosis on conventional and high-resolution CT and determine their impact on patient survival. Materials and methods: Conventional helical and high-resolution CT images of 12 patients with invasive pulmonary aspergillosis were evaluated with respect to the presence of nodules, masses, segmental or peribronchial consolidations, centrilobular nodules, ground-glass halos, and cavitation. The imaging findings were compared with the survival of patients. Results: Spiculated nodular opacities ranging from 0.5 to 3 cm were a constant finding in all patients. These were accompanied by segmental areas of consolidation in 4, and peribronchial consolidations in 2 patients. Four patients had centrilobular nodules. Seven patients demonstrated either crescentic or central cavitations. Halos of ground-glass attenuation were observed in 10 patients. Seven patients succumbed 3 -10 days after the examination; 4 of these had segmental, 2 had peribronchial consolidations. Five patients benefited from the antifungal treatment; 4 of these showed some form of cavitation. The overall mortality rate was 52 %; however, mortality increased to 80 % in patients without cavitation, and decreased to 42 % in those with cavitation. None of the patients with segmental or peribronchial consolidations survived. Conclusion: The most frequent computed tomography finding of invasive pulmonary aspergillosis consists of spiculated nodular opacities often surrounded by ground-glass halos. Half of the patients have accompanying segmental or peribronchial consolidations, which remarkably increase the mortality. The presence of cavitation, observed in a slightly higher percentage of patients, indicates a more favorable prognosis compared to those without this finding. In the past years there has been an increase of extensive operative procedures in the surgery of malignant thoracic tumors. Several studies have been exposed concerning the normal and pathological appearance of the postoperative chest X-rays, but very little is present in the literature about what we can see on CT scans. After major lung surgery the normal anatomy has changed, because of the redistribution of the remaining structures, hyperexpansion of the non operated lung, retraction of the intercostal spaces, elevation of the hemidiaphragm, due to the lack of the lung or part of it. The radiologist should be familiar with the various operative procedures of the chest in order to accurately interpret the modifications that have occurred, and to distinguish what is normal and what is pathological. We propose different major intervenctions, following various pathologies; the resulting normal aspects on X-rays and CT scans are distinguished between early and late appearances

The thoracic complications of intravenous drug abuse -a pictorial review K.S. Mayilvahanan, A. Smethurst, N.J. Beeching, J.M. Curtis; Liverpool/GB Intravenous drug abuse (IVDA) is a common problem in European countries and is becoming an increasing problem in developing countries. Complications may arise as a direct result of intravenous injection or secondary to the effects of immunosuppression. Any organ system can harbour these complications. The Radiology Department is often called upon to establish the diagnosis. We present a pictorial review of radiology of thoracic complications of intravenous drug abuse on plain radiographs and computerised tomography. (3) Present algorithms approaches to SPN diagnosing. Material and methods: Ten nonspecific SPN that were identified on thin-section CT were studied with PET. The final diagnosis was established with surgical resection due to the positive result in PET. We exhibit the representative cases and quiz for instructive purposes. Results: Factors as suboptimal imaging technique and failure to review prior studies in CT and false positives in PET, may result in an inappropriate diagnosis of malignancy, leading added morbidity of invasive diagnostic or therapeutic procedures. Conclusions: CT, PET and image-guided biopsy should be used as part of multimodality approach to patient management, and decisions should be discussed with the radiologist and other caregivers to determine the cost-effectiveness and safety of the procedure for each patient. False positives with PET imaging may contribute to the incorrect assessment of therapeutical decisions in these patients with SPN. Other radiological techniques as image-guided biopsy and early repeat CT to determine nodule growth may correctly classify SPN and avoid the resection of benign nodules.

Helical computed tomography features and 3D reconstruction of right paratracheal air cysts P. Antonopoulos, E.A. Liapi, A. Petroulakis, K.S. Malagari, G. Malahias, C. Stoupis; Athens/GR Localized dilatation of the trachea may present pathologically either with the structure of tracheocele or with thin-walled diverticulum, found almost exclusively on its right side. The term paratracheal air cyst depicts the radiological presentation of these pathologically described entities. Aim: To describe the helical CT appearance, as well as the three-dimensional reconstructed pattern, of paratracheal air cysts. Material and methods: Nine patients (6 male and 3 female, age range: 43 -78 years, mean age: 59.3 years) were identified as having right paratracheal air cysts during the past four years (1997 -2001) . Helical CT scans were obtained with a collimation of 4 mm and a table increment of 4 mm. IV contrast medium was used in most of the scans. In order to obtain more anatomical details, multiplanar reformatted images and three-dimensional images were reconstructed.

Results: All paratracheal air cysts were situated in the right posterolateral aspect of the trachea. Five paratracheal cysts were located at the level of T1 vertebral body and four at the level of T2 body. Three-dimensional CT images clearly demonstrated the nature of the air cysts and their communicating thin lumen to the trachea. Conclusion: Paratracheal air cysts located on the right posterolateral aspect of the trachea are most commonly associated with COPD and are likely to represent pathologically described tracheal diverticulae and tracheoceles. The radiologic features of the above air cysts in the thoracic inlet, as shown by helical computed tomography and three-dimensional reconstruction, have been rarely described in the current bibliography.

US and CT imaging findings of the pleural effusions and atelectasis after upper abdominal surgery L. Rossi, S. Bromberg, A. Sestari, J. Gonçalves; São Paulo/BR Purpose: To determine with US and CT the incidence of radiological changes in the pulmonary parenchyma and pleural space (pleural effusions and atelectasis) following upper abdominal surgery. Methods and materials: Prospective study of 37 patients (21 women and 16 men) with an age range from 29 to 76 years (mean 56.11 ± 13.20) who underwent abdominal surgery in the period from 28 June 1999 to 7 November 2000. Preoperative and 48 hours postoperative US and CT of the chest was performed in all patients, excluding those with radiological changes in the pulmonary parenchyma and pleural space at preoperative examinations. The US and CT findings were described and classified in grade 0, I, II and III (pleural effusions and atelectasis). Various risk factors intrinsic to patients and due to anaesthetic/surgical procedures were correlated with these radiological changes. Results: 30 patients (81 %) presented radiological changes in the pulmonary parenchyma and pleural space: 8 (21.5 %) grade III and 22 (59.5 %) grade II and I. The pulmonary changes grade I at III were significantly associated with risk factors: age > 40 years, surgical incision > 30 cm, surgery for cancer resection and the use of nasogastric tube after surgery (p < 0.05). The time of hospitalisation was longer in the pulmonary changes grade II/III. The prophylactic antibiotic did not decrease the incidence of these pulmonary changes. Conclusion: We confirmed that CT and US are accurate techniques to identify and grade pulmonary changes following upper abdominal surgery, showing higher incidence, compared to literature. A significant relationship exists between pulmonary changes grade II/III and patients who underwent surgery for cancer resection that used nasogastric tube postoperatively.

Can chest X-ray be included in a decisional algorithm for patients suspected of pulmonary embolism diagnosis? G. Barghouth, J.O. Prior, J. Cornuz, A. Bischof Delaloye, P. Schnyder; Lausanne/CH Purpose: To evaluate the agreement among physicians in interpreting chest X-ray for patients with suspected pulmonary embolism. Subjects and methods: Chest X-ray: We randomly selected 40 chest X-rays from a population of hospitalized patients in the emergency room for pulmonary embolism. Physicians: Attending fellows (n = 20) from 3 specialties (8 internal medicine, 9 radiologists and 3 nuclear physicians) performed the chest X-ray reading. Procedure: Physicians classified each X-ray in two categories according to simplified criteria based on the PIOPED study. The reader had to determine whether abnormalities or lesions impeding the interpretation of the scintigraphy were absent (group 1) or present (group 2). Results: X-rays were classified in group 1 in 70 % of the cases by radiologists and in 40 % by non-radiologists. Within a given specialty, there was a good agreement among physicians in categorizing X-rays (Pearson c2, p > 0.377). Contrariwise, there was a significant difference among specialties (p < 0.06). The difference was significant for the absence of lesion (group 1, p < 0.06) and for pleural effusion (group 2a, p < 0.1). It was particularly significant for parenchymal lesions (group 2b, p < 0.002) and other lesion types (group 2c, p < 0.001). Conclusion: There was a good agreement in classifying X-rays within a given specialty. Radiologists found more X-rays in group 1 than the non-radiologists. It was especially true when technical artifacts were interpreted as lesions or abnormalities by non-radiologists. The chest X-ray should not be used in a decisional algorithm of patient with pulmonary embolism suspicion because of the lack of agreement among specialties.

Anomalous venous pathways within the lung: Plain film and crosssectional findings J. Cáceres 1 , J.M. Mata 2 , J. Andreu 1 , E. Castañer 2 , S. Quiroga 1 , X. Gallardo 2 , E. Pallisa 1 ; 1 Barcelona/ES, 2 Sabadell/ES Purpose: To present unusual variants of anomalous paths of thoracic veins within the adult lung, the majority of which can be recognized or suspected in the chest radiograph and confirmed with cross-sectional studies (CT or MRI). Material and methods: Forty-one adult patients were studied with PA and lateral conventional radiograph (41 cases), CT (40 cases), MRI (14 cases) and angiography (9 cases). Results: The following variants were found: meandering veins (3 cases), single pulmonary veins (4 cases), scimitar syndrome (25 cases), levo-atrial cardinal vein (1 case), partial venous drainage to systemic veins (6 cases) and azygos continuation within an azygos lobe (2 cases). In the great majority of cases, the plain film findings suggested the diagnosis of these variants. Their definitive diagnosis was made with CT or MRI studies. Conclusion: Venous variants of the lung can be suspected in conventional radiograph and easily confirmed with cross-sectional studies, avoiding more invasive techniques.

Vascular lesions and proliferations within the thorax: A radiologicpathologic overview T. Franquet 1 , P. McAdams 2 , A. Giménez 1 , J.J. Erasmus 2 , S. Rossi 2 , S. Bagué 1 ; 1 Barcelona/ES, 2 Durham, NC/US In this exhibit, we review the radiologic findings of a broad and diverse spectrum of vascular lesions and proliferations within the thorax. These lesions, which may be congenital, acquired or neoplastic in origin, include arteriovenous malformations, aneurysms and pseudoaneurysms, hemangiomas and lymphangiomas, diffuse hemangiomatosis and lymphangiomatosis, hepatopulmonary syndrome and vascular sarcomas. Because many of these entities have characteristic findings on chest radiographs, CT or MR imaging, this exhibit will help practicing radiologists better understand and recognize these interesting disorders. Helpful clues for ap- propriately narrowing the differential diagnosis and for directing patient management will be discussed. In addition, the pathologic basis for the radiologic findings will be emphasized in appropriate cases.

Contribution of CT in pulmonary hypertension A. Resten, S. Maitre, J. de Laveaucoupet, B. Castanedo, D. Musset; Clamart/FR Purpose: To describe the CT findings of patients with pulmonary hypertension (PH) according to the new OMS classification of PH (Evian 1998) in order to distinguish CT manifestations of pre-and postcapillary pulmonary circulation. Method and materials: Didactic study with retrospective analysis of CT of patients admitted to our hospital for a severe PH from 1996 to 2000 (n = 700) (disorders of the respiratory system excluded) and radiopathologic confrontation. Pulmonary CT protocol included a CT angiography and a high resolution CT (HR-CT). Results: CT angiography and HR-CT often allow to separate the different forms of PH, despite similar clinical presentations: primary pulmonary hypertension, pulmonary venous hypertension, chronic embolic disease or due to disorders affecting the pulmonary vasculature. Conclusion: CT angiography can demonstrate proximal thromboembolic disease, leading to a specific treatment by thromboendarterectomy, and HR-CT findings can be very suggestive of postcapillary venous hypertension (pulmonary venoocclusive disease and/or pulmonary capillary hemangiomatosis), contra-indicating a medical treatment by prostacyclin.

A practical morphologic approach to the classification of anomalies of the aortic arch C. Beigelman-Aubry 1 , Y. Badachi 1 , J.-P. Akakpo 1 , S. Lenoir 1 , G. Gamsu 2 , P.A. Grenier 1 ; 1 Paris/FR, 2 New York, NY/US Purpose: To simplify the description of congenital anomalies of the aortic arch by using a practical classification system. Material and methods: 20 selected cases were retrospectively analyzed using the current classification and the proposed one. CT (n = 14) and/or MRI (n = 8) were performed. The classification system was based on the position of the supra aortic vessels (transversal anomalies), the aortic arch (vertical and transversal anomalies), the descending aorta (transversal anomalies), and on the caliber of these vessels (stenosis, ectasia). Results: Single anomalies of position as right aberrant subclavian artery (n = 6) or caliber as coarctation of the aorta (n = 5) were easy to classify. When complex anomalies (n = 9) as double aortic arch or cervical aorta were present, classification with the proposed system was also always easy conversely to the former system. Conclusion: A system that details each anomaly on the basis of its abnormality of (1) position and (2) calibre -with reference to the normal situation -is an improvement. This proposed classification includes all of the potential aortic anomalies and facilitates their analysis.

Natural history of type B (Stanford) aortic intramural hematoma C. Sebastia, C. Medrano, S. Quiroga, R. Dominguez, R. Boyé, A. Alvarez; Barcelona/ES Purpose: To review the evolution of type B (Stanford classification) aortic intramural hematoma as depicted by means of helical CT. Methods and materials: Since 1993, 19 cases of type B aortic intramural hematomas have been diagnosed and followed-up in our hospital. In all cases the diagnosis was performed with CT, and CT was used to survey the aortic changes after acute onset, at 1 month, 6 months and yearly thereafter. Starting in 1995, helical CT was used for this purpose. Results: Of the 19 cases, total reabsortion of the intramural hematoma with reduction in the aortic diameter was demonstrated in 9 cases (47 %). Among the 10 remaining cases (53 %), 5 developed ulcer-like projections (localized blood-filled pouch protruding from the aortic lumen), 4 saccular aneurysms (eccentric dilatation involving one side of the aorta) and 1 fusiform aneurysm (dilatation involving the entire aortic circumference). Four of the 19 cases initially developed mediastinal hematoma that resolved spontaneously. In the follow-up of dilated aorta, 6 cases were managed conservatively, 2 cases underwent open surgery and in 2 an endoprosthesis was implanted. Conclusion: Aortic intramural hematoma is a dynamic process that must be closely followed. Although approximately half the cases healed spontaneously, the other half developed ulcer-like projections and aneurysms that had to be treated to pre-vent aortic rupture. This exhibit depicts the evolution of intramural hematomas by means of helical CT, with 2-and 3-dimensional reconstructions that permit a graphic visualization of aortic changes.

Diagnosis value and limits of strategy combining D-dimer, ultrasound and CT angiography in the diagnosis of acute pulmonary embolism S. Garcia-Asensio, L. Sarria, M. Martinez-Berganza, E. Gomez, M. Quintana, F. Lameiro, P. Chueca; Tudela/ES Purpose: To asses the clinical usefulness of strategy combining D-dimer, US and CT angiography in outpatients with suspected pulmonary embolism (PE). Material and methods: 73 outpatients in whom CT angiography was performed because of clinical suspicion for PE were retrospectively studied. Risk factors and symptoms of PE were recorded. The examinations were performed with a Pro Speed SX GE scan (3 mm collimation, 1.5 reconstruction interval, pitch of 1:1). The patient was scanned in the caudal-cranial direction, before and during the injection of contrast. Results were classified according to the Sinner description (partial filling defect, total filling defect, "railway track" sign and mural defect) and its location. 29 patients with clinical findings consistent with deep venous thrombosis underwent US (Toshiba Powervision 6000, 7.5 linear-array trasducer). In 60 patients D-Dimer was evaluated with ELISA assays methods, the cut-off being 500 mg/ml. SROC analysis of these techniques were estimated. Results: CT angiography demonstrated PE in 30 of 73 patients (4 in central vessels, 14 in central and subsegmental vessels and 12 in subsegmental vessels only). Partial filling defect was detected in 20 patients, total filling defect in 12, "railway track" sign in 6 and mural defect in 1. In 24 patients CT showed other diseases. The sensitivity of the D-dimer assay was 88 %; specificity 37.5 % and NPV 80 %. Conclusion: Strategy combining DD, US and CT angiography may be of special interest in outpatients with suspected PE. CT angiography has capacity to diagnose other diseases that may simulate PE, however is unable to show the majority of subsegmental emboli.

Usefulness of spiral CT angiography and perfusion scintigraphy in the detection of pulmonary embolism A. Zapasnik, T. Bandurski, E. Szurowska, M. Studniarek; Gdansk/PL Aim of the work was comparison of the diagnostic value of perfusion scintigraphy both in planar and SPECT mode with sCT and the multimodality image fusion of sCT and SPECT. Methods: 30 patient with confirmed PE were included in the study. Imaging protocol consisted of planar scintigraphy in 6 projections, SPECT study, and chest sCT angiography. Sensitivity, specificity, PPV and NPV were estimated both for each modality separately and for SPECT and sCT computer fusion. Spiral CT was performed with 3 mm slices thickness, pitch 1 -1.5 and 1.5 mm reconstruction interval. Intravenous injection of 120 ml contrast material is done at rate 4 ml/s by power injection within 15 s delay time. Results: In 25/30 patients sCT angiography was positive for PE and was confirmed in 21 cases by scintigraphy (planar and SPECT). In 3 patients the negative result of sCT angiography for PE didin't agree with scintigraphy. In 2 cases the good diagnosis of PE was possible as a result of the multimodality image fusion of sCT and SPECT. Conclusions: High diagnostic value of both sCT and scintigraphy (planar and SPECT) was confirmed. The specificity of sCT angiography was higher than scintigraphy in the detection of emboli in central and segmental pulmonary arteries. The scintigraphy was more sensitive in depicting circumferential PE. The multimodality image fusion of sCT and SPECT was an accurate method in the early diagnosis of PE.

Guidelines for the diagnosis of aortic dissection after blunt trauma of the chest with spiral CT angiography B.V. Salamousas, F. Cademartiri, G. Luccichenti, P. Zuccoli, P. Pavone; Parma/IT Purpose: To assess the value of spiral CT angiography in the demonstration of traumatic dissection of thoracic aorta and develop solid diagnostic guidelines. Methods and material: 11 patients with traumatic dissection of thoracic aorta were studied with spiral CT, transesophageal echocardiography and aortic DSA. 2 patients died within 24 hours after the trauma and 1 died because of the aortic lesion. 3 patients underwent surgical repair, 2 underwent intra-vascular stenting

Chest while 1 patient was followed clinically with pharmacological therapy. The criteria used to chose the correct therapeutic path are reviewed following the results of our series and the latest literature on spiral CT angiography. Results: All the patients studied with spiral CT had DSA confirmation but the information provided by CT was more accurate and included accessory findings. It influenced therapeutic approach in 5 patients. Main clinical-radiological guidelines are given. Conclusion: Spiral CT angiography can play a major role in the first diagnostic approach to patients suspected for traumatic dissection of thoracic aorta.

Can malpositioned central venous catheters be diagnosed on routine chest CT? E. de Kerviler, M.-C. Douard, P. Bourrier, S. Kacimi, F. Lallouet, S. de Géry, A.-M. Zagdanski, J. Frija; Paris/FR Purpose: Because many patients with central venous catheters undergo chest CT examination in the course of their disease, we aimed to demonstrate to which extent CT was able to recognise catheter malposition. Methods and materials: We retrospectively analysed the cases of catheter dysfunction or malposition that were referred to us to attempt repositioning. From our radiological database, we searched for the patients who underwent chest CT examination during the days or weeks preceding the procedure. We then reviewed these CT examinations in order to detect the abnormalities that were misdiagnosed at first reading. Selected cases with previously missed malpositioned central venous catheters on routine chest CT examination are shown. They are selected to illustrate the most common catheter pathways and the main causes of diagnostic errors. Results: Malpositioned central venous catheters are commonly depicted on chest radiograph when abnormal angulation is seen, or when the tip of the catheter is clearly in an inappropriate vessel. However, the posteror-anterior view fails to detect aberrant catheter locations when these malpositions project onto the shadow of the superior vena cava, and misdiagnoses malpositioned catheters in case of anomalous venous pathways. Abormalities detected with CT were loops of the catheter, catheter positionned in an inappropriate vessel, tip of the catheter against a vein wall, catheter breakage or catheters exiting the vascular lumen. Conclusion: CT is able to detect most of central venous catheter abnormalities. Ongoing vigilance in checking of the position of the catheter on chest CT is mandatory to reduce potential hazards.

Rational approach to confirm or exclude a diagnosis of pulmonary embolism by spiral CT angiography D. Spitzer, P. Vojtisek; Pardubice/CZ CT imaging plays a major role in the evaluation and the differential diagnosis of patients suspected of having pulmonary embolism. Purpose: To achieve highly sensitive and 24 hour accessible method for emergency patient to confirm or exclude a pulmonary embolism. Material and methods: In the regional hospital with 850 beds which serves a population of 180000 inhabitants, almost 300 patients were evaluated by spiral CT between October 1999 and September 2001 for suspected pulmonary embolism. An older scanner with 1 second scanning time and collimation of 5 mm (Shimadzu SCT 4000) was used in 50 % of them and spiral scanner with 0.75 second time and collimation of 3 mm (Shimadzu SCT4800) was used in the other 50 %. All investigations were analysed in cine mode on the workstation for the presence of direct and indirect signs of pulmonary embolism. Correlation between D-Dimmer measurement, deep venous thrombosis assumed by ultrasound and pulmonary embolism assumed by CT scanning were established and a rational algorithm was created for this purpose. Results: Pulmonary embolism was diagnosed in 127 patients, representing 0.36 pulmonary embolisms per year per 1000 inhabitants. Conclusion: CT pulmonary angiography has a valuable role in the investigation of patients with suspicious pulmonary embolism. Although interpretation can be difficult, the technique is able to exclude embolism with fair confidence. Furthermore CT is able to identify other occult diseases. With D-dimmer measurement helps to exclude a clinical significant pulmonary embolism and important venous thrombosis.

Mediastinum C-0276 MR imagings of bronchus-associated lymphoid tissue lymphoma (Baltoma) T. Kobayashi, Y. Shibata, T. Gabata, O. Matsui; Kanazawa/JP Purpose: The purpose of this study was to describe MRI findings on pathologically confirmed bronchus-associated lymphoid tissue lymphoma (BALToma), a rare primary pulmonary neoplasm, in 4 patients and to evaluate patterns of dynamic neoplasm enhancement. Material & methods: Two chest radiologists reviewed 1.5 T MRI findings on four patients. MRI was performed according to the following protocol; pre-contrast fast spin-echo T1WI with ECG gating, fat-suppressed fast spin-echo T2WI with respiratory gating and dynamic contrast SPGR images following rapid injection of Gd-DTPA. Signal intensities from T1WI and T2WI of the lesions and dynamic intensity curves were evaluated and compared with their pathological backgrounds. Results: Three lesions appeared in the lung field and one in the left main bronchus. On T1WI, homogeneous hypo-intensity was exhibited in all cases. On T2WI, homogeneous moderate hyper-intensity was exhibited in three cases, and heterogeneous hyper-intensity in one case. The latter lesion had pathological scar areas around the BALToma. In two cases, the 'MR angiogram sign' was manifested in the lesion. The dynamic curve showed moderate increase in signal intensity until the second minutes in all cases. These MR findings corresponded well with their pathological backgrounds, which included homogeneous cell-rich neoplasm spreading around the pulmonary interstitium. Conclusion: MR findings on BALToma exhibit good pathological correlations. It is hoped that MR examination will play a greater part in the differential diagnosis of BALToma.

The retrotracheal space: Normal anatomy and pathological appearances T. Franquet 1 , J.J. Erasmus 2 , A. Giménez 1 , R. Prats 1 ; 1 Barcelona/ES, 2 Houston, TX/US The retrotracheal space is a radiolucent anatomic area outlined anteriorly by the posterior tracheal wall, posteriorly by the thoracic spine and inferiorly by the aortic arch. A variety of mediastinal and lung disorders may be detected either on plain films or cross-sectional imaging methods. The aim of this exhibit is to provide a broad overview of abnormalities that may be detected in this anatomic space. CT and MR imaging are useful for the evaluation of this space. We will discuss different entities including vascular abnormalities (aberrant right subclavian artery, right aortic arch, double aortic arch, and left subclavian artery), esophageal abnormalities (benign and malignant tumors, duplication cysts, Zenker's diverticulum, and achalasia), and miscellaneous abnormalities (intrathoracic goiter, lung carcinoma, cystic hygroma).

CT signs of left heart luxation in posttraumatic and postoperative cases T. Leibecke, J. Gellissen, H.D. Weiss; Lübeck/DE Purpose: To determine CT-findings in pericardial rupture with left heart luxation. Materials and methods: Chest CT scans of 4 patients with intraoperatively proved pericardial rupture were reviewed for signs of cardiac luxation. Results: Dislocation of the heart, myocardial septum displacement to an angle of more than 90°, pneumothorax and pneumopericardium were seen in all patients. In 3 patients a pathologic strangulation was seen between the left atrium and the left chamber by the aorta that could be responsible for low cardiac output. 

Materials and methods: A retrospective study of 25 patients (15 males, 10 females) with a diagnosis of acute descending necrotizing mediastinitis (ADNM), postoperative and posttraumatic mediastinitis was performed during the last 15 months. Operative and CT findings were compared. Results: Soft tissue inflammation was observed in 25 patients (100 %), mediastinal emphysema in 25 (100 %), pleural effusion in 18 (72 %) (bilateral in 15), abscess formation in 17 (68 %) (multiple in 12), lung infiltrates in 16 (64 %) (bilateral in 15), adenopathy in 13 (52 %), pericardial effusion in 11 (44 %), sternal dehiscence in 14 (56 %) post-operative patients and pleuro-mediastinal fistula in one patient. All patients with clinical findings of mediastinitis had primary CT findings. The sensitivity and specificity of CT for ADNM and posttraumatic mediastinitis was 100 % and 100 % respectively. In postoperative patients CT sensitivity and specificity was 100 % after the second postoperative week, though before the second week CT had a sensitivity of 100 % and a specificity of 38 %. Conclusions: CT is the diagnostic modality of choice in evaluating acute mediastinitis. It clearly delineates the location and extent of the pathology. Early diagnosis by CT is essential for a favourable outcome and potential survival. Clinical healing of median sternotomy does not correlate with the CT findings, although CT images are indicative of acute mediastinitis after the second postoperative week.

CT and MR imaging of thymic epithelial tumours: Imaging findingspathologic correlation and evaluation of usefulness for differentiating noninvasive from invasive tumours J. Sadohara, K. Fujimoto, H. Terasaki, R. Kono, M. Uchida, H. Nishimura, N. Hayabuchi, S. Kato; Kurume/JP Purpose: To evaluate and compare the CT, MR, and pathologic findings of thymic epithelial tumours. Methods and materials: A total of 54 patients with thymic epithelial tumour who underwent MR imaging were examined. There were 25 men and 29 women. The mean age was 56 years. The study included 26 patients with stage I (non-invasive thymoma), 18 with invasive thymoma (3 with stage II, 14 with stage III, one with stage IVa), 1 with atypical thymoma, and 9 with thymic carcinoma. 29 of 54 patients also underwent CT scan. CT and MR images were analyzed for follows: tumour size, location, margin, intratumoural findings of septum, nodular lesion, homogeneity, calcification, hemorrhage, necrosis, invasiveness of adjacent mediastinal structures, dissemination, mediastinal and/or hilar nodes, and extra-mediastinal metastases. Results: The margins of invasive tumours were more irregular than those of noninvasive thymomas (p < 0.05). The visualization of the margin on CT was clearer than that on MR imaging. MR imaging was superior to CT in detecting the capsule. The finding of a whole capsule was detected in only 6 non-invasive thymomas. Intratumoural findings of MR imaging were more detectable than those of CT. The more frequent findings in invasive tumours were intratumoral inhomogenous signal (p < 0.001), presence of necrosis (p < 0.05), and findings of invasiveness (p < 0.01). Conclusion: CT and MR imaging clearly showed pathologic features of thymic epithelial tumours. Analysis of the details of imaging findings might distinguish non-invasive thymomas from invasive thymomas or thymic cancers.

Thoracic nodal staging in bronchogenic carcinoma with thin-section dynamic electron beam tomography (EBT): Evaluation of morphological signs of mediastinal and hilar lymph nodes metastases T. Nakazono, Y. Matsuo, R. Noguchi, S. Kudo; Saga/JP Purpose: To evaluate the accuracy of thoracic nodal staging in bronchogenic carcinoma with thin-section dynamic EBT that has less partial volume effect and less motion artifact compared with conventional helical CT, and to evaluate a criterion for morphological signs of mediastinal and hilar lymph nodes metastasis. Materials and methods: We reviewed EBT finding and pathological findings of lymph nodes (total 289 stations, 68 metastatic stations) in 77 patients (58 males and 19 female, with a mean age 67) with resectable bronchogenic carcinoma. EBT was performed with continuous volume scan, 3 mm thickness and 3 mm interslice gap covering lung mass and whole mediastinal and hilar lymph node stations during the bolus injection of 100 ml contrast material. Initially, lymph nodes larger than 10 mm (15 mm only for subcarinal region) diameter in a short axis on thin-section EBT were considered metastatic and sensitivity, specificity and accuracy were evaluated. Then, another criterion, in which node with following characteristics on thin-section EBT were excluded, was also evaluated: (1) mediastinal lymph nodes had adipose tissue of lymph node hilum inside, (2) hilar lymph nodes of which margins were concave to lung parenchyma.

Results: Sensitivity, specificity and accuracy were 75 %, 82 % and 80 % with the initial criterion, and were 72 %, 91 % and 87 % with the second criterion. Conclusion: Dynamic thin-section EBT that can reveal detail of lymph nodes is useful for nodal staging in bronchogenic carcinoma. To improve diagnostic accuracy of lymph nodes metastasis, morphological signs should be evaluated, as well as their size.

MRI evaluation of residual mediastinal masses in Hodgkin's disease: A review of 40 patients with long-term follow-up G. Cerone, E. Di Cesare, S. Carafa, G. Della Porta, V. Tombolini, C. Masciocchi; L'Aquila/IT Purpose: To evaluate the role of MRI in distinguishing fibrous from active residual masses in treated Hodgkin's disease and to verify whether the use of I.V. paramagnetic contrast medium could provide additional information. Materials and methods: Forty patients with residual mediastinal masses underwent MRI after therapy (1, 6 and 12 months). A 1.5 T magnet, and T1 and T2weighted sequences were used; in 37 patients I.V. contrast medium was administrated. Size, signal intensity on T2-weighted images and contrast enhancement of residual masses were evaluated. A long-term MRI follow-up (5 years) was then performed. Low signal intensity and low contrast enhancement were considered signs of inactive mass; homogeneous high signal intensity and remarkable contrast enhancement were indicative of active disease; inhomogeneous signal intensity and contrast enhancement were related to partial remission and/or presence of colliquative necrosis and/or radiotherapy induced inflammation. Results: We examined 32/40 patients after chemotherapy and 28, post chemotherapy and radiotherapy. 2 cases, classified as active pattern on the basis of T2weighted sequence, showed colliquative inactive residues after Gd-injection. At the 6 months follow-up the use of contrast medium led to change in opinion about disease activity in 3 cases, proving to be useful in increasing MR specificity, easily distinguishing colliquative non enhancing areas within the residual mass. The long term follow-up confirmed the diagnosis. Conclusion: MRI is indicated when the activity of Hodgkin's disease has to be defined in residual masses. In some cases the I.V. administration of contrast medium may improve MRI diagnostic accuracy.

Technical Aspects

Comparison of the visualisation of anatomic structures in the chest using computed radiography (CR) and digital radiography (DR) with different processing parameters correlated with the level of observer confidence in interpretation of these structures J.A. Verschakelen 1 , W. De Wever 1 , A.-K. Carton 1 , N. Ooms 2 , F.A.J. Dhaenens 2 , E. Vandenbossche 2 ; 1 Leuven/BE, 2 Antwerp/BE Purpose: To compare anatomic structures normally depicted on chest radiographs acquired with CR and DR techniques using different processing parameters and to assess observer's confidence in the interpretation (normal vs. abnormal) of these structures. Material and methods: 50 CR and 50 DR PA chest radiographs were randomly selected from our data files. All images were obtained with dedicated chest units (CR: Siemens Digiscan); (DR: Agfa ADR THORAX) In addition to the established parameters for each system both image sets were also post-processed using MUSICATM. Eight observers (2 chest radiologists, 4 radiology residents and 2 last year medical students) studied these 4 sets of images. The image quality (visualisation) of 6 anatomic structures was graded on a 5-point scale. In addition, the readers also indicated on a 5-point scale their level of confidence on the interpretation (structure confidently normal to confidently abnormal). Results: Postprocessing significantly improved the visualisation of the tracheacarina, the para-oesophageal line, and the retrocardial lung on both CR and DR radiographs and the lung vessels on DR radiographs. Visualisation of rib 2 and right hilum was not improved. Post processing only increased the observer confidence in the interpretation of the para-oesophageal line on the DR films. Conclusions: Although postprocessing resulted in an improved visualisation of 4/6 studied anatomical structures in the chest, it's influence on the observer confidence of interpretation of these structures was limited.

Usefulness of temporal subtraction for the detection of interval changes of interstitial lung diseases on chest radiographs T. Ideguchi 1 , T. Muranaka 1 , R. Miyajima 1 , F. Akazawa 1 , N. Tabata 1 , H. Ikeda 1 , Y. Higashida 1 , M. Ohki 1 , F. Toyofuku 1 , K. Doi 2 ; 1 Fukuoka/JP, 2 Chicago, IL/US Objective: To demonstrate the clinical utility of a temporal subtraction technique for the detection of interval changes of various interstitial lung diseases. Materials and method: 34 patients (16 men and 18 women) with various interstitial lung diseases were selected from our database obtained with a computed radiography (CR) system, which included interstitial pneumonia (n = 16), bronchiolitis obliterans organizing pneumonia (BOOP) (n = 3), acute eosinophilic pneumonia (n = 3), hypersensitivity pneumonitis (n = 2), diffuse panbronchiolitis (n = 1), amyloidosis (n = 2), lymphangitis carcinomatosa (n = 2), sarcoidosis (n = 3) and rheumatic pneumonia (n = 2). One hundred temporal subtraction images were used; 37 images without interval changes, and 63 with interval changes. The clinical usefulness of temporal subtraction on diagnostic accuracy for detection of interval change was investigated by using the ROC observer performance study. Four radiologists and two chest physicians participated in observer studies using a sequential test. Results: The Az (area under the ROC curve) values obtained without and with temporal subtraction were 0.78 and 0.90, respectively. Results showed that the detection of interval changes of interstitial lung diseases was significantly improved by use of temporal subtraction images compared with CR images alone (P < 0.002). Furthermore, the high detection rate was achieved with temporal subtraction images regardless of the subtlety and locations of interval changes. Conclusion: The temporal subtraction improved the diagnostic accuracy of radiologists for detection of interval changes of interstitial lung diseases on chest radiographs. It was also useful for cases with ad multiple interval changes.

3D Bronchoview: A new software package for investigating airway diseases C.I. Fetita 1 , F. Preteux 1 , C. Beigelman-Aubry 2 , P.A. Grenier 2 ; 1 Evry/FR, 2 Paris/FR Purpose: To introduce a user-friendly package providing 3D reconstruction, visualization and navigation tools for the bronchial tree.

Windows/UNIX workstations. It inputs a gray-level volume obtained from a sequence of 1.25 mm-thick axial scans from multislice CT acquisitions, and outputs a 3D semi-transparent rendering of the sole extracted airways. The 3D reconstruction method relies on a diffusive-aggregative Markovian modeling, which takes advantage of the structural and topological features of the airways. The central axis of the bronchial tree is automatically computed as well as the plane orthogonal to the central axis on any point of the selected bronchial segments. This makes possible an accurate estimation of the bronchial lumen and wall areas. Results: Volume rendering-based visualization and navigation capabilities ensure a complete and easy investigation of the bronchial tree. 3D CT bronchograms provided good visual assessment of bronchiectasis, bronchial stenoses, and bronchial wall irregularities, even on distal bronchi beyond the 6 th order. CT acquisition at a lung volume pneumotachographycally controlled, allows the monitoring of the airways caliber and wall thickness on successive examinations of a given patient. Conclusion: The 3D Bronchoview package contributes to increase the confidence level of diagnosis of morphologic abnormalities of the airways. It is a valuable tool for in-vivo and non-invasive monitoring of airway measurements in longitudinal studies in patients with COPD and asthma.

Three-dimensional tracheobronchial tree CT in neoplastic and inflammatory disease S.M. Torres del Río, J.M. García Santos, M. Corral de la Calle, M. Martínez; Murcia/ES Purpose: To show three-dimensional bronchial patterns in lung inflammatory and neoplastic disease. Material and methods: We reviewed the chest spiral CT raw data in 27 patients with suspected lung cancer. They were classified in two groups according to final histological diagnosis: 23 neoplastic cases (11 epidermoid, 6 adenocarcinoma, 2 giant cell carcinoma, 1 anaplastic carcinoma, 1 microcytic carcinoma, 1 atypical carcinoid, 1 metastasis) and 4 pneumonias. Raw data were used to obtain 2D, 3D-SSD and 4D-bronchographic perspective images. The three-dimensional tracheobronchial tree was evaluated looking for stenosis, obstructions, and wall irregularities. 2D images were considered the gold standard for analysing the threedimensional findings. Results: Both neoplastic and inflammatory diseases lead to patterns where bronchial stenosis and amputations are mixed. Nevertheless, complete obstructions are typical in neoplastic disease and more infrequent in inflammatory cases. Moreover, stenosis in the inflammatory disease tend to be more concentric and regular than in neoplastic cases. In the two most frequent subtypes of our lung cancers, bronchial amputations were more common in cases of epidermoid carcinoma than in adenocarcinomas. Rough obstructions were more frequent in epidermoid carcinomas, opposite to the more progressive stenosis and amputations in adenocarcinomas. Because of the few cases of other histological subtypes in our series, the imaging data obtained from them were less valuable. Conclusion: Three-dimensional reconstrucctions of the tracheobronchial tree are not able to differentiate neoplastic from non-neoplastic disease, or determine the probable neoplastic histological subtype is. The different patterns reported could still be of some help.

Determining the scanning parameters in the case of lung examinations with a multi-slice CT scanner (method of obtaining the maximum clinical information with the minimum exposure dose) K. Shibata 1 , K. Tsujioka 2 , Y. Ida 2 , S. Fukada 1 , A. Nagata 3 ; 1 Toyota/JP, 2 Toyoake/JP, 3 Neo Gifu/JP Purpose: To determine the optimal scanning parameter settings for lung examinations using Single-Slice CT and Multi-Slice CT helical scanners. We focused on the image properties, exposure dose, and time required for an examination. Materials and methods: We altered the Helical Pitch, mA, slice collimation, and slice thickness of the images. We then examined the images of different scanning parameters by measuring image noise, SSPz, effective slice thickness, and exposure in an effort to identify scanning parameters for obtaining quality images with low exposure. Results: The Multi-Slice CT scanner required only about a third of the exposure a Single-Slice CT scanner requires in ensuring the same image quality. In other words, exposure to the patients was reduced by about 15 percent by changing the scanning parameters. Conclusion: When using a Multi-Slice CT scanner, image properties, exposure dose, and time required for an examination change dramatically depending on the scanning parameter settings. The results have confirmed that a Multi-Slice CT scanner ensures quality images with low exposure by setting optimal parameters.

Depiction of minute structures of the lung parenchyma using new superfine resolution CT H. Moriya 1 , S. Miyashita 2 , T. Katakura 1 , K. Suzuki 1 , M. Miyazaki 1 , M. Okumura 3 , T. Rifu 3 ; 1 Fukushima/JP, 2 Sapporo/JP, 3 Otawara/JP Purpose: The secondary pulmonary lobule is a structural unit that is composed of pulmonary parenchyma. However, it is difficult to clearly visualize the structures in the conventional CT scanner. The objective of this study is to depict the pulmonary lobular structures using a new super fine-resolution CT. Methods and materials: CT scanner used: Aquilion (Toshiba). In a four-row detector a virtual offset of plus 1/8 channel for the first and second row and minus 1/8 channel for the third and fourth row is set. In order to achieve this virtual offset a mask is used for each channel. The complementary data is superimposed between the normal data. The sampling pitch of the raw data from this system is 4 times finer than usual scanning. The spatial resolution of this new CT scanner is 0.2 mm in the simulation, and the measured value for the actual machine is 0.25 mm. Normal volunteers and inflated fixed lung specimens were examined. Results: In the volunteer study, interlobular septa, small pulmonary veins, centrilobular arterioles and bronchioles were depicted. In the fixed lung specimen study, bronchioles of the diameter of 0.8 mm or less were depicted. With regard to bronchi peripheral to the 6 th -9 th level, a larger number of bronchi could be depicted compared with the non-amended Aquilion CT scanner. Conclusion: High contrast resolution CT of 0.25 mm can be achieved by employing this reconstruction method and detector design. This technique makes it possible to depict the pulmonary lobular structures.

Application of a method for changing the tube current during helical scanning with a multislice CT scanner M. Kojima 1 , S. Itoh 1 , M. Ikeda 1 , N. Watanabe 1 , N. Watanabe 2 , M. Ozaki 2 , H. Satake 1 , S. Koyama 1 , T. Aoyama 1 , T. Ishigaki 1 ; 1 Nagoya/JP, 2 Tokyo/JP Purpose: To clarify whether a method for changing the tube current during helical scanning is useful for the equalization of image noise in various sections of the body without increasing the dose in multislice CT. Materials and methods: This method determined the optimal tube current for each rotation based on local absorption measured with a scanogram. In baseline studies, the dose and time required for the changes was monitored continuously and in real time during scanning to validate this method. One hundred examinations of the liver and lung were randomized into scans with constant tube current and scans with this method. The dose, the SDs of measured CT numbers, and the dispersion of the SDs among various sections were compared. Results: This method permitted the tube current to be precisely changed and a time of 250 ms was needed to change the tube current by 50 mA. In the liver, the average dose and SDs per examination was equal for all scans. In the lung, the average dose and SDs according to this method was lower or higher, compared with standard scans respectively. The differences in the SDs among various sections of both the liver and lung were significantly smaller in scans with this method than in standard scans. Conclusion: The method of changing the tube current during scanning makes it possible to equalize the image noise in various sections of the body without increasing the dose in multislice CT.

Spiral CT of the thoracic aorta with 3D volume rendering techniques C.P. Kalogeropoulou, G. Kagadis, P. Zabakis, I. Tsota, D. Karnabatidis, D. Dougenis, T. Petsas; Patras/GR Purpose: Application of volume rendering techniques (VRT) in the assessment of thoracic aorta abnormalities. Materials and methods: Spiral computed tomography (CT) examinations were performed in 8 patients: 3 patients had congenital thoracic aorta abnormalities (tetralogy of Fallot with a right aortic arch and the right subclavian artery originating distally and developing a vascular ring, causing dysphagia (1), coarctation (1), and a patient following distal hemiarch replacement and graft replacement of the left subclavian artery), as well as in 5 patients with aneurysms of the thoracic aorta. Data sets were acquired with a Somatom Plus 4 Power scanner (Siemens) in deep inspiration with administration of contrast medium (140 ml at 4 ml/s). All data were transferred to a Magic View 1000 workstation where they were processed. The steps consisted of editing the transverse slices in order to discard all the data except the thoracic aorta and its branches, adjusting the trapezoid parameters and the opacity of the aorta in order to produce transparent lumen. Results: Transparent VRT images proved to be very helpful in the diagnosis of thoracic aorta abnormalities since they reveal greater anatomical and morphological detail compared to the conventional transverse CT. They also provide adequate information for the orientation of the aorta in the thorax. In all cases the overall processing duration was 5 -15 minutes. Conclusion: Transparent VRT is diagnostic for the confirmation of the thoracic aorta abnormalities. Furthermore it is a quick and non-invasive technique for the evaluation of the thoracic aorta.

Optimization of contrast media injection in SCT in the diagnosis of pulmonary embolism F. Gattoni, B. Tagliaferri, P. Scali, S. Brioschi, F. Boioli; Milan/IT Purpose: Aim of this paper is to introduce a method of automatic CM injection in the diagnosis of pulmonary embolism. Materials and methods: The CARE bolus software pilots an electronic trigger that, in a right atrial ROI, first monitors CM passage and then starts acquisition procedure when the enhancement's intensity reaches a predetermined level. Our SCT has 6 s delay between trigger's "OK" and start of acquisition. During this time, CM passes into the pulmonary veins enhancing it, making more difficult the diagnosis of pulmonary embolism. This problem was solved injecting a low-speed bolus before the CM injection. This makes the trigger start the sequence in advance so that acquisition is performed while CM is enhancing just the pulmonary arteries before subsequent veins' opacification. We evaluated, in 80 patients, the enhancement, the imaging result, the time needed and the total amount of CM injected. Results: There were no diagnostic artifacts caused by enhancement of pulmonary veins. The average time needed per procedure was below 30 min. The average volume of CM injected was 130 ml (first bolus: 30 ml, main bolus: 100 ml). Conclusions: The diagnosis of pulmonary embolism requires a correct enhancement of vessels coupled with a precise timing of the start of acquisition procedure at the moment of maximum enhancement. This method is easy to learn, useful, with no added reading difficulties, well accepted by patients and with no important controindications.

Half dose contrast material with ultra-fast injection method in thoracic dsiorder using MDCT N. Hashimoto, M. Miyazaki, H. Honjyou, H. Moriya, F. Shishido; Fukushima/JP Purpose: To evaluate the usefulness of ultra-fast intra-venous injection method with half dose contrast material in Multi-detector CT studies of thoracic disease. MDCT parameters were 4-DAS, minimum 0.5 mm collimation and 0.5 s (X-ray tube rotation) scan time.

We performed ultra-fast power-injection in 8 ml/s (total volume 40 ml) with saline or 5 % glucose flush after contrast media injection. (1) We tried helical two phase scanning (first scan: 5 -10 s post injection and second scan: 15 -20 s) to separate the pulmonary artery contrast phase, pulmonary vein, and thoracic artery contrast phase. PA phase was scanning from hilum to the lesion and PV & aorta phase was scanning from the lesion to the hilum. Collimation was 2 mm (HP: 5.5) or 3 mm (HP: 3 -3.5). We performed whole lung scan (collimation 1 -2 mm) with 60 ml contrast material. (2) We tried dynamic scanning (0 -40 s, 4 section: collimation; 2 -3 -5 mm) for continuous observation on same section. We performed in pulmonary carcinoma, mediastinal tumour and AVF etc. We performed whole lung scan (collimation 1 -2 mm) with 60 ml contrast material. Results: (1) Two phase helical scan obtained 3-dimentional information. It separated pulmonary artery phase from pulmonary vein-thoracic artery phase, evaluated pulmonary vessel invasion in pulmonary carcinoma and separated bronchial artery and inter-costal artery from thoracic artery. (2) Dynamic scan was obtained in venous disorder, arterial feeding distribution of lung & mediastinal tumour. We easily diagnosed hyper-vascular tumours (including venous disorder). Conclusion: Half dose, high rate injection method was useful in obtaining 3D information making differential diagnosis.

Fine needle biopsy of the chest lesions under X-ray television control referred to planimetric measurements using prior CT images in patients with claustrophobia or breathing difficulties J.G. Glowacki, T. Legaszewski, J. Harasim, W. Sraga; Zabrze/PL Purpose: All patients who were referred for fine needle biopsy (FNB) had CT performed before, which was the basis of initial diagnosis as well as an indication for biopsy. Biopsy under CT control was not always available or could not be performed (patient's claustrophobia, breathing difficulties in prone or supine position). Aim of the study: to present the possibility of performing a fine needle biopsy as a result of calculations done on the basis of prior CT. Material and methods: Material includes 58 patients from Pulmonary or Chest Surgery Departments. Diagnosis, qualification for FNB and location of tumour, its size and biopsy channel were defined on the basis of prior CT. There was no need to perform subsequent CT examination since FNB on the basis of former CT under X-ray television control was performed. Results: 91 % of the lesions were confirmed by cytology. There was no difference between these data and the results obtained in our series of CT guided biopsies, but most of the tumours were big (over 5 cm in diameter 65 %) and were situated close to the chest wall.

To obtain cytological material -if anatomy conditions are good enough and biopsy under CT control is not possible -FNB can be performed under X-ray television control referring to the planimetric calculation using former CT images with almost equal results and precision.

Multi-detector CT bronchial arteriography (CTBAG); trial for determining the optimum scan parameters M. Miyazaki, Y. Igarashi, N. Hashimoto, H. Moriya, F. Shishido; Fukushima/JP Purpose: To evaluate the efficacy of depiction of bronchial arteries (BA) using multi-detector CT by the low dose injection of contrast medium (CM) for embolization or infusion. We show the optimum scan parameters for depiction of BAs by CTBAG in this study. Materials and methods: We prospectively performed both CTBAG using AQUILION with V-detector (TOSHIBA) and intra-arterial digital subtraction angiography (IA-DSA) in 14 patients with lung cancer and/or hemoptysis. The major scan parameters of CTBAG were 3 mm collimation, 3 -5.5 helical pitch and 1.5 mm reconstruction interval. The CM (300 -370 mg I/ml, 2.5 -8 ml/s, 40 -100 ml) was injected into the median vein and scanning was started at 15 -20 seconds after injection. The respiratory discontinuance period was less than 15 seconds in all patients. The depiction of BAs was evaluated with the axial, multiplanar reconstruction and volume rendering images (Zio M900 workstation, Zio Software Inc.), and all of CTBAG findings were compared with IA-DSA. Results: In 13 of all patients performed CTBAG we were able to depict BAs clearly and this findings agreed with IA-DSA observation. BAs were not depicted by CTBAG in one patient because the BAs were very thin as seen from IA-DSA findings. We considered that the optimum scanning parameters for CTBAG were 3 mm collimation or thinner. In addition the injection rate was 2.5 ml/s and the amount of CM required was at least 40 ml. Conclusions: We can depict the BA by multi-detector CT angiography by low dose injection of CM and determine the optimum scan parameters for CTBAG.

The development of an active image filter to aid internet browsing for radiology education and research J. Revell, C. Burgess, M.R. Rees; Bristol/GB Background: Searching for relevant radiology images on the Internet can be a timeconsuming and frustrating experience. An active user-friendly matrix preview of images to select images together with a display of associated relevant web links has been developed to aid radiology teaching and research byfacilitating fast relevant image searching. Materials and methods: The project was implemented by construction of a client server application operating in a web browser. The server side was capable of processingsynchronised multiple threads to provide efficient crawling of hundreds of webs page. Facilities were incorporated to filter only black and white or colour images and also to determine search of image type. Systems were also introduced to prevent inactive sites stalling the search by using URL time-outs. The software could accommodate multiple client requests using instance pooling. The software allowed for typing in key words or phrases or specific URL search. Results: Initial research demonstrated that the software could be transferred onto any desktop or laptop computer and could be used effectively by non-experts. Experts and non-experts demonstrated relevant radiology images with virtually all searches. The potential for the software was rated as high by a group of radiology trainees. Conclusion: Non-computer experts and radiology trainees demonstrated that the active image filter was user friendly and effective in desktop and laptop environments.

Pitfalls at 2D and 3D reconstructions A.A. Manolitsas, D. Melidis, S. Stratilati, I. Tsitouridis; Thessaloniki/GR Purpose: To demonstrate the pitfalls that can be noted during the processing of original CT scans in 2D and 3D reconstructions. Method and materials: We studied 52 bone lesions, 44 vascular lesions and 19 lesions of airway. The examinations were performed using a Picker 5000 Spiral CT scanner and a Picker Voxel Q visualization workstation. The original CT scans were reconstructed in 2D and 3D models with the following techniques: MPR, CR, MIP, mIP, SSD, VRT, and VE. Results: We describe pitfalls by virtue of wrong thresholding, wrong segmentation, projective falls, incomplete technically examinations and swallow operation. Conclusion: The 2D and 3D reconstructions contribute in the diagnostic accuracy of SCT. But for the avoidance of pitfalls should be studied in the presence of the original CT scans as a complement to them. Otherwise they may lead to overestimation or underestimation of certain pathologies. It should be noted that the quality of the 2D and 3D reconstructions depends on the quality of the original CT scans. 

In 22 patients with varying cardiac diseases endocardial borders were detected either manually or semi-automatically (seeded-ROI). Subsequently the right and left ventricular volume-ejection-fractions were calculated. Two investigators defined the endocardial borders for both ventricles using both methods. For statistical analysis two-factorial analyses of variance were performed for the four variables: VEF right ventricle, VEF left ventricle, required time right ventricle, required time left ventricle (SAS, Anova). Results: There was no user (p = 0.9613) or method effect (p = 0.3095) detectable for both ventricles. The required time for both ventricles did not reveal a user effect, but there was a significant method effect (p < 0.0001) concerning a reduction of the required time for analysis for both ventricles > 50 %. 

Conclusion: The semiautomatic mode for detecting the endocardial borders in determining right and left ventricular ejection fractions did not demonstrate results differing from the results of the manual method, but is significantly superior concerning the time required for analysing ejection fractions of both ventricles with a reduction of more than 50 %, which might reduce the cost for personnel.

3D post-processing techniques: A teaching file G. Luccichenti 1 , F. Cademartiri 1 , R. Cobelli 1 , R. Raaymakers 2 , G.P. Krestin 2 , P. Pavone 1 ; 1 Parma/IT, 2 Rotterdam/NL Purpose: To illustrate optimal scan and reconstruction parameters for the 3D visualization high and low density structures in order to identify the more practical and accurate method for clinical applications.

A phantom with multiple solids with different densities and shapes were evaluated with Somatom Plus 4 and a Somatom Volume Zoom (Siemens, Erlangen, Germany) scanners. Different parameters and multiple reconstructions were performed (28 protocols with the single detector scanner: collimation 1/2/3/5 mm, pitch 1/1.5/2, rot. time 0.75, increment 1/3/2/5 mm, soft tissues convolution kernel, FOV 300 mm. 30 protocols with the multidetector scanner: collimation 0.5/1/2.5/5 mm, effective slice 0.5/1.25/3/6, pitch 3/6, rot. time 0.5 s, increment 0.3/1/2/3/5 mm, soft tissues convolution kernel, FOV 300 mm). Images were stored in DICOM format in CD-ROM and installed in an HP workstation running on a Window NT platform equipped with a Vitrea 2.2 software which allows the performance of MPR, MIP, Volume Rendering reconstructions, linear measurements and volumetric analysis through manual segmentation. Different curves and algorithms were used for each scan. Two radiologists evaluated source images and 3D reconstructions of each protocol and the artifacts were recorded. Results: Higher image quality was obtained using smaller collimation and reconstruction increment although the volume coverage has been limited for collimation inferior to 2 mm on single detector scanner. Spike curves resulted in more accurate for 3D reconstruction of low contrast objects. Conclusion: 3D visualization of low contrast structures is feasible in a phantom model but segmentation problems occur in vivo.

Volume estimation: An overview of different techniques G. Luccichenti, F. Cademartiri, C. Branchi, P. Pavone; Parma/IT Purpose: The chemotherapy and radiotherapy response in clinical oncology is related to the tumour volume and is determined according to the WHO criteria. In this case the product of two linear measurements is performed. More recently other authors proposed to use a single linear measurements for the same purpose (RECIST). On the other hand postprocessing techniques are now available, allowing one to estimate accurately the tumour volume. Aim of this study is to assess the validity of different methods of volume measurement. Methods and material: Scientific papers concerning volume measurement, including experimental and human studies, were reviewed by two radiologists. All data were evaluated with particular attention to design of the studies, technique, mathematical approximations and the results. For each technique advantages and lacks were identified and recorded. Results: Unlike linear measurement technique volume estimation by manual semiautomatic or automatic segmentation is less operator dependent, provides more accurate results, is reliable for volume variation analysis and is a reproducible technique. In linear measurement technique, interobserver variability can be up to 30 % depending on the lesion shape density and size. The use of 3D techniques entails a different therapy response classification of the patients. Conclusion: Three-dimensional volume assessment is an accurate technique and should be used for clinical trials because of its reproducibility. Displaying the admission to release of final report interval, we found a two-peak diagram, with the first peak corresponding to a release of final results on the same day and the second peak to a release on the following day. This explains the great variability of the admission to findings-release period, shown in the comparatively big values of standard deviation. Comparing the mean values we find, that mammography and sonography images take considerably longer than chest, abdomen and skeletal X-ray.

Proposal of a software for computer-assisted bone age assessment F. Gattoni, G. Ceriani, F. Vimercati, F. Boioli; Milan/IT Purpose: Skeletal maturity diagnosis is usually based on a visual comparison of a left-hand wrist radiograph with atlas patterns. We propose a bone age assessment software that integrates two numeric methods (Sempé; and TW2).

The software we developed is based on the two methods following this scheme: TW2 for males and females under 16; Sempé; for females over 16; TW2 for males between 16 and 18; Sempé; for males from 18 to 19. Radiographic images illustrate the degrees of skeletal maturity and are presented with caption useful for numeric assessment. Images are sorted by maturity stage from an age of 12 to 18 -19. The assessment is performed on a computer monitor where is also presented the differential score for both sex. The correct stage of skeletal development is assessed extracting the values of age for every bone and final age is the sum of single age values.

The software integrates the two numeric methods TW2 and Sempé; in a fast and reliable way. The time needed to obtain final score for each method is 10 -15 minutes for Sempé, 8 -10 minutes for TW2 and 3 -5 minutes with our software. Another advantage is reduction of computational errors in both score and bone age that often occur using paper as a support for evaluation. A further costs and time reduction is obtained sending by e-mail the assessment's results to authority that made the request.

Inner ear: Imaging with SCT and 2D and 3D reconstructions A.A. Manolitsas, D. Melidis, A. Morichovitou, I. Tsitouridis; Thessaloniki/GR Purpose: To demonstrate the applications of 2D and 3D reconstructions in the imaging of the structures of the inner ear. Method and materials: We studied 24 cases, 15 male and 9 female, aged 24 to 52 years old (mean 36 a). The examinations were performed using a Picker 5000 Spiral CT scanner and a Picker Voxel Q visualization workstation. Thickness: 1 mm, pitch: 1, overlap: 50 % (0.5 mm), algorithm: sharp, DFOV: 60 mm, focal spot: small, spiral interpolation: sharp. The axial CT scans were reconstructed in 2D and 3D models with the following techniques: MPR, SSD, VRT, VE. Results: MPRs proved valuable in studying the vestibule, semicircular canals and cochlea; giving images of same diagnostic value with the axial CT scans in several perspectives. VRT was especially useful in viewing auditory osseous. SSD provided images with more sense of depth and was useful to the collecting information about the bony structures of the internal acoustic meatus. Virtual endosopy as an application of the volume rendering technique was useful in producing 3D images of the inner surfaces of external ear, tympanic cavity and labyrinth.

The 2D and 3D reconstructions as a complement of the axial CT scans have many applications in study of the inner ear providing images that can be studied in any perspective. Consequently we consider that they offer an overall evaluation of the area that we examined without the accessory radiation of the patient for the coronal CT scans.

Artificial intelligence in analysis of radiological data of the chest T. Achenbach, T.W. Vomweg, C.P. Heussel, M. Thelen, H.-U. Kauczor; Mainz/DE Purpose: Processing of radiological images of the chest using computer science has received growing attention from the radiological community during recent years. The availability of digital data sets and the increasing amount of data are ideal prerequisites for image post-processing. At the same time, they represent enormous challenges for the development of appropriate software tools. Systems for processing of digital data, manually or visual extracted data and non radiological data have been developed and evaluated. Introduction into daily clinical work routine of radiologists is infrequent. This poster will review different kinds of artificial intelligence methods used and the main fields of application. Methods and materials: Based on a literature review of more than 50 papers current developments in artificial intelligence in analysis of radiological data of the chest are summarized. Results: Segmentation of chest X-ray and CT/MRI images is the basic task before further processing can be applied. Simple threshold based systems and adaptive sized neural networks are used. Volume measurement is the next step and can be performed by using the data gained from segmentation. The Barnhard method and modified methods are used for chest X-ray images, voxel-addition is used in CT and MRI. Detection and quantification of pneumonia, emphysema and fibrosis and pulmonary nodule detection are further goals of AI in chest radiology. Technical approaches comprise density masks, single or multiple artificial neural networks and linear discriminant analysis classifiers fed with statistical and fractal texture parameters. Conclusion: Introduction of software tools for analysis of chest image data is imminent. Nodule detection and segmentation of anatomical or pathological structures could be the first wide spread applications.

Virtual laryngoscopy - 

We have tackled the problem of large Voxels on the laryngological feature scale by applying a local average low pass filter to the segmented binary object data interpolated on a grid sufficiently finer than scannerresolution. The filtered object volume and the original get perspectively rendered seperately. The images get adequately merged. The software we wrote is basically a platform independent being based on AVW and Tcl/Tk. We run the system on a Pentium III (450 MHz) and SGI O2. Render method and concept-of-software get evaluated by surgeons and radiologists. Results: In order to test acceptance and effect of task oriented imaging in preoperative planning we have designed an experimental VL system providing for perspective flights through the Larynx including optional object information. On the laryngological feature scale we find volume rendering qualitatively outperforms surface rendering significantly. We achieve good subjective correspondence of VL with Laryngoscopy. Conclusion: Task oriented modular software engineering may support modern imaging techniques in every day clinical usage when the complexity of user interaction can be reduced to a first-sight-intuitive set of events. This may be interpreted in terms of switching-costs and tradition-of-imaging.

Clinical evaluation of 3D display on low-end PC's by a single hospital network-integrated visualization computer M.C. Freund 1 , R. Wegenkittl 2 , M. Rieger 1 , M.F.H. Schocke 1 , K.M. Unsinn 1 , W.R. Jaschke 1 ; 1 Innsbruck/AT, 2 Brunn a. Gebirge/AT Purpose: 3D display of MRI-or multislice spiral-CT-acquired data volume facilitates radiologic evaluation and enhances clinical communication. The increasing clinical demand for 3D display as well as the improving image-resolution requires until now expensive, dedicated 3D workstations as stand-alone solution in the proximity of the imagers. In order to decrease cost and increase clinical availability for 3D display a de novo solution was sought.

A commercially available high performance computer (VolumePro Net®, RTVis) equipped with several volume-rendering boards (VolumePro 500-2X®, RTVis) was connected via the hospital network to 6 lowend PC's at various imaging and clinical sites within a distance range of up to 6000 m. The installed system supported simultaneous, state-of-the-art rendering features (e.g. volume-rendering of large imaging studies with > 250 images and 512 × 512 matrix, real-time parameter changes) of routine clinical cases as well as archiving of color-rendered jpeg-and mpeg-files. In order to test the clinical efficiency 6 different data-volumes (e.g. CT/MRI-angiography of the renal arteries, thoracic aorta and hand as well as 3D display of complex tumors of the chest and spine) were rendered separately on each of the 6 different low-end PC's utilizing an identical rendering-protocol.

All clinical examples were rendered on the different PC's within the same time interval (± 10 s); image-qualitiy was rated identical by 4 different readers. Conclusion: A reliable 3D display of MRI and CT data-volumes can be implemented on different low-end PC's utilizing a single hospital network-integrated visualization server.

An ultrasound-focused multimedia database with a confidential, multi-level thematic access: Performance and limitations Y. Koumpouros 1 , G. Minadakis 2 , I. Theocharakis 1 , D. Cavouras 1 , I. Theotokas 1 , C. Hatzimichail 1 , P. Zoumpoulis 2 , S. Faitaki 2 ; 1 Athens/GR, 2 Kifissia/GR Purpose: This paper deals with the development of a multimedia database and is focused on serving the real needs of physicians working with diagnostic ultrasound. The limitations of such a database, as well as the results of using it are analysed in this paper. Methods and materials: A lot of efforts are related to the development of a medical database in various sectors. This project relates to the design and development of an ultrasound-focused multimedia database with multi-level thematic access. Our major aim during the development phase was to satisfy the real needs of the end-users. Another significant problem was the size of the stored images and videos, their format, etc. The use of wavelets and other techniques proved to be valuable for such a scheme. The whole system works over the Internet using a simple browser. All the issues related to security and confidentiality have been taken into account. Results: The overall objective was to develop a user-friendly formula that any physician with only the basic computer knowledge could use. The use of this multithematic database under an experimental phase between three countries, six hospitals and a significant number of physicians proved its value and flexibility for educational purposes. Conclusion: More than 50 real cases have been transmitted, stored and processed via this database. Problems concerning the size of US images and videos are resolved and confidentiality is assured. The redesigning of different modules of the system is in progress.

"A walk across radiology" -A multimedia application for practice pregraduate teaching on radiology F. Sendra-Portero, E. Ristori-Bogajo, M. Martínez-Morillo; Málaga/ES Purpose: Training on visual perception is an essential task in the teaching and learning process of radiology. A multimedia application focussed in this subject is presented after more than three years of performance at our institution.

The application is designed as a case collection of different image modalities, with higher proportion of plain film X-rays modalities, organized in normal or pathologic images. After to see each case the user goes to the response screen where several commentaries and marks are shown with animated transitions. This application has been presented as a part of the programmed practice lessons to the students of the last course at the Faculty of Medicine in Málaga (Spain) during the last 3 years, spending a time between 6 and 4 hours. After this, the students completed a voluntary questionnaire about performance with computers, evaluation of the applications and open suggestions. Results: During these 3 years, the application has been edited in CD-ROM, distributed between students and professors of our country, and adapted to html to be integrated as a web-based-training resource. Currently, the second version is presented with new cases, better images quality and translated into English. This exhibits presents both versions to be compared and the report of the questionnaires completed by the students. Conclusion: Web-based-training and e-learning radiology is usually focused to residents or specialist. In exchange, our project is directed to pregraduate or general practicioner basic training on diagnostic image semiology. The contents are organised in three chapters of chest sequential CT; anatomy, technique and lung cancer. For the current version, the original multimedia contents have adapted to a PowerPoint set of presentations controlled by the user by on touch click of the mouse on active buttons, images or text. Results: This exhibit presents the original version (in Spanish) to be compared with the current version (bilingual) in .ppt and .html formats. Results of users tests at different levels (students, residents, specialist) are also presented. Conclusion: Even when it was designed for radiology residents training the original version of AULAGA was demonstrated to be very useful to pregraduate teaching purposes. The new versions allows us to select different ways to see the information. We are working on: (1) the addition of new chapters (2) the inclusion of quizzing modules and (3) Aim of the study was to substitute drawers or folders of a conventional slide archive with a new database of radiological images. It is also based on Web Technology. The program has been prepared on a PC (Pentium III, 700 MHz, RAM 128 Mbyte, HD 20 Gbyte), using the 4 th Dimension platform. We can archive images in different format (JPG, PCT, BMP). Few comments are added to the images, including data and findings, name and archive number. Each image is classified according to the technique (CT, MR, etc.), pathology or organ. The user can access the database using one of these parameters. If a conventional slide has also been archieved, the location in the archive is displayed. We used this program in substitution of conventional slide archive or conventional images for teaching and preparation of conferences. We found this program very flexible and very easy to use. In our experience we obtained optimal results. Medical Images Organizer (M.I.O.) has been created to be a very flexible digital images archive.

Open source in radiology: The Raynux project C. Saccavini, P. Mosca, R. Stramare, S. Puggina, D. Miotto, A. Ramelli, G. Feltrin; Padova/IT Purpose: To realize a low-cost PACS system using open source software and a new archiving strategy. Materials and methods: In our department we use a self made PACS based on Linux Server with Interbase 6.0 as database engine and a DICOM server application developed starting from OFFIS library (Oldenburg Germany). The network is a 100 Mbit/s FastEthernet. We have connected to our PACS one CT (Emotion by Siemens), one MR (Armony by Siemens), two CR (AC3 by Fuji), one digital radiography (Advantix by GE), two reporting workstation (MagicView by Siemens, HiC 655 by Fuji) and four PC-based reporting workstations. To archive the radiological images we use high capacity fast hard disks instead of optical disk jukebox: infact the cost of 500 Gbyte online HD archive is 7 • per Mbyte agaist 26 • per Mbyte of optical disk Jukebox. We back-up all the images on CD-ROM in order to have an offline legal archive. Results: The PACS system in these 6 months has worked very well; the users appreciate the very fast time of image retrivial due to high performance of hard disks. The high number of backup CD-ROM suggest us to change the media support to DVD in the next months.

The new opensource software changes the traditional approch in planning PACS systems: new strategies are incoming. In the next months we plan to distribute our software on Internet as an open source project.

The unified patient project: A case based teaching tool for integration of different medical fields P. Pokieser 1 , J. Brandstätter 2 , S. Hönigschnabel 1 , S. Steinböck 1 , M. Memarsadeghi 1 , M. Scharitzer 1 , B. Partik 1 , M. Hörmann 1 , A. Ba-Ssalamah 1 ; 1 Vienna/AT, 2 Wiener Neudorf/AT Purpose: To create a web based computer application, which can integrate different medical fields into a data bank for case based teaching. Methods and materials: A database for case histories was developed. The backbone of the database is the time. All patients events of disease, diagnosis and treatment are ordered along their timing. Further, history, symptoms, physical examination, diagnostic approach (laboratory medicine, imaging, pathology, others like endoscopy or E.E.G), therapy and outcome are frames, which escort the description of events and the placement of media. Three parts of the software, constructed separately, have to be mentioned: modules for the case histories, the didactic techniques and administration. The didactic module is independent from the case database and can be designed individually according to the didactic purpose and the expenditure of time and costs. Behind the three modules, there is a collection of evaluated web links and articles, which is under continous cultivation, structured pertinent to the frames of medical work flow to allow a quick switch between patient read out, tasks from the didactic module and research. Results: The application is now in test for the problem based new student curriculum in Vienna. Full original case histories are loaded and are used for different purposes of trainig and case presentations on the intranet (internet under construction). Conclusion: The unified patient project could facilitate multidisciplinary teaching of clinical cases. Based on server technology, the application is limited by the transfer rate of data. Methods: Signal intensity in MR images was measured in tumor, blood, liver, kidney and muscle after application of Gd-HSA over a period of 144 hours. MRI results were correlated with tumor histology using Gd-and fluorescein-HSA. Results: Compared to liver and kidney the tumors showed a delayed accumulation with maximum at 24 hours after application. Histologic and fluorescence evaluation demonstrated localization in tumors predominantly in stroma and necroses. Conclusion: Gd-HSA efficiently accumulates in squamous cell carcinomas grown in nude mice. The use of low loaded Gd-HSA in MRI may offer relevant opportunities for the discrimination of tumors sensitive to a therapy with cytostatica-labeled albumins. Additionally this contrast agent can also be used for MR-angiography.

Ultrasound microbubble contrast agents: Frequently asked questions, tips and protocols A. Papatheodorou, F. Takis, S. Lyra, P. Galani, N. Mpatakis; Athens/GR The introduction of microbubble based ultrasound contrast agents (USCA) has expanded the implementation and diagnostic range of ultrasound. In this pictorial essay, presented in the form of a questionnaire, the most important aspects of USCA imaging are presented, including the basic principles of microbubble contrast imaging, the equipment requirements, the existing and developing protocols of examination, the limitations of this technique as well as useful tips for the beginners. General reference is made to normal and pathological findings depending on the examined area. Reference is made also to the current areas of investigation and development (functional studies, more stable agents etc.). Upon review of this poster, the participant will be able to:

1. Understand the principles of intravenous microbubble based ultrasound contrast agents, their clinical applications and limitations. To assess the efficacy of ultrasmall superparamegnetic iron oxide (Sinerem, Guerbet, France) in the differentiation of metastatic and benign lymph nodes. Material and methods: MR studies were performed with 1.5 T superconducting imaging sistem (GE Signa Horizon 8.3 Echo Speed, Milwaukee, USA). Seven adults suspected of having lymph node metastases underwent MR examination 24 -28 hours after intravenous infusion of Sinerem. Two radiologists interpreted the post-contrast modification of signal intensity of the lymph nodes on the T2* weighted gradient-echo images. MR findings were compared with histopathologic findings at the corresponding site. Result: Twelve lymph nodes were available for histopathologic examination. Histopathologic examination showed 7 normal nodes and 5 metastatic nodes. All metastatic nodes showed an increase in signal intensity on postcontrast GRE T2*weighted MR images. Five normal nodes showed decrease in signal intensity, indicating active USPIOs uptake by macrophages. Two normal lymph nodes, with increase in signal intensity, were interpreted as positive. In this case, the examination presented more artefacts. MR showed sensitivity of 71 %, specificity of 100 % and accuracy of 82 %.

This study suggests that USPIOs might be used to facilitate the differentiation between metastatic and benign nodes. Additional studies are needed to confirm these data.

Comparison between liver-specifc and vasculo-interstitial contrast agents in the detection of solid benign focal liver lesions A.V. Giordano, M. Sabatini, O. Michelini, P. Pagano, M. Polito, E. Di Cesare, C. Masciocchi; L'Aquila/IT Purpose: To verify the diagnostic potentials of different paramagnetic and superparamegnetic contrast media in detecting and characterizing solid benign focal liver lesions. Methods and materials: Twelve patients with US evidence of solid benign focal liver lesions (8 cases of focal nodular hyperplasia and 3 cases of adenoma) were submitted to MR examination. 3 different constrast agents were employed in all cases Mn-DPDP (Teslascan, Guerbet), Gd-BOPTA (MultiHance, Bracco) and SPIO particles (Endorem, Guerbet). The study was carried on employing a 1.5 T unit (GE Horizon), using breath hold T1-w SPGR sequences before and after (fat-sat) i.v. injection of Mn-DPDP and Gd-BOPTA (dynamic and hepato-specific phase), T2-w sequences (Single Shot Half Fourier) and T2*-w fast GE sequences after SPIO particles injection. Biopsy was performed in all cases. Results: All lesions appeared isointense with respect to normal parenchyma before and after i.v. injection of Mn DPDP and during the liver-specific phase of Gd-BOPTA due to the up-take in the hepatocytes. Dynamic study after i.v. injection of Gd-BOPTA showed a rapid and strong enhancement during the arterial phase in all of them. The absence of RES inside the tree adenomas determined a hyperintense appearance, upon a dark liver, using the SPIO particles, all FNH instead appeared to be isointense to the liver. Biopsy confirmed MRI findings in all cases.

We consider all MR contrast agents useful in confirmation of the benignity of focal lesions. The agent selected depends on each particular case. In the case of suspicion of adenoma we suggest the use of hepatocytic agents.

What contrast medium agent for spiral defeco-computed tomography to evaluate pelvic floor dynamics? A new contrast agent mixture composed by ourselves A. Salzano 1 , V. Nocera 1 , E. Rossi 1 , C. Caprarelli 1 , L. Nunziata 2 , E. Minelli 1 , A. Nunziata 2 ; 1 Frattamaggiore/IT, 2 Naples/IT Purpose: The aim of this study is to illustrate a new contrast agent, with high density, simulating the fecal bolus, and suitable to perform Spiral Defeco-Computed Tomography (SDCT). To describe its preparation and composition, and the results obtained on 48 patients. Materials and methods: Our series comprised 48 patients (44 females and 4 males; mean age of 56 years and range of 45 -78 years) examined with SDCT. We made a high density contrast agent mixing potato starch (70 %), methylcellulose (25 %) and high density barium (5 %) at 113 % weight/volume obtaining a cream substance. We preferred potato starch as densifier material, because we noted that after 2 -3 minutes from the beginning of preparation, the fluid cream became spontaneously thicker due to the high hydrophily of potato starch. Results: We took advantage of natural distension of bladder avoiding urination 3 hours before CT exam, direct evaluation of pelvis content such as muscles, uterus, pouch of Douglas and intestinal loops. SDCT showed 39 cases of rectoceles, 22 cistoceles, 19 perineal descent syndromes, 11 cases of fecal incontinence, as well as 8 cases of enteroceles and 5 of sigmoidoceles. Conclusion: The contrast medium mixture permitted an excellent distension of anorectum and vagina; the natural content of bladder and intestine were well visualised in order to recognize urinary and intestinal pathologies related to pelvic floor disfunctions. Our contrast medium agent and the natural contrast of bladder and intestinal loops added to Spiral Computed Tomography method, allowing a unique imaging approach to pelvic floor. 

• incidence, physiopathology, risk factors, • therapeutic options (nothing, surgery), • our local experience in the management of subcutaneous extravasation. During 3 consecutive years, a high number of patient were referred to our plastic surgery department which is a referral center in Paris for extravasation of contrast material. During the first year, most patients (51/52) were operated (lipo aspiration using saline with xylocain). During the second year, only patients presenting with severe cutaneous signs were operated (12/29). During the third year, nobody was operated whatever the clinical symptoms. Only one complication in the first group was observed. Conclusion: Extravasation of contrast material is not a rare event using spiral CT and power injectors. The rate of complication is very low. Two major risk factors are: use of ionics and extravation in the hand and foot. Surgery is very rarely indicated. A clinical follow up the next day is necessary.

Oral contrast agent administration for helical CT cholangiography (HCT-C): Comparison between three different protocols O. Catalano, A. Nunziata, U. Pagliari, A. Siani; Naples/IT Purpose: To compare three different protocols of administration of the contrast agent for HCT-C. Methods & materials: 90 subjects scheduled for HCT-C for a variety of hepatobiliopancreatic disorders were randomised into three groups. Cholecystectomy patients were excluded. Iopanoic acid tablets were given orally. 30 subjects in Group 1 received 6 g of contrast agent in the evening before the examination (total dose 6 g); 30 in Group 2 received 3 g in the morning and 3 g in the evening the day before the study (total 6 g); 30 in Group 3 received 3 g in the evening on the first day, 3 g in the morning and 3 g in the evening before the study (total 9 g). Results: A 2 mm 2 region of interest measured the attenuation at level of the gallbladder (mean 510 HU for Group 1, 522 HU for Group 2, and 520 HU for Group 3), hepatic duct (mean 120 HU for Group 1, 140 HU for Group 2, and 145 for Group 3), and common bile duct (mean 319 HU for Group 1, 340 HU for Group 2, and 337 for Group 3). Visualization quality found the common bile duct adequately opacified in 93 for Group 1, 97 % for Group 2, and 97 % for Group 3; the cystic duct adequately opacified in 83 % for Group 1 and 87 % for Group 2 -3; the common hepatic duct adequately opacified in 87 % for Group 1 and 90 % for Group 2 -3, the right and left hepatic duct in 80 % for Group 1 and 2, and in 83 % for Group 3. Conclusion: Fractionating into two doses the usual 6 g dose of iopanoic acid for HCT-C increases both subjectively and objectively the image quality, probably because of a greater stimulation of the enterohepatic circle.

Optimal contrast material injection protocol for the whole body survey using multislice CT K. Awai 1 , K. Hiraishi 1 , S. Hori 1 , H. Onishi 2 , K. Takada 3 ; 1 Izumisano/JP, 2 Sakai/JP, 3 Tokyo/JP Purpose: Multislice CT (MSCT) has high volume coverage speed and it is suitable for the whole body survey in the lymphoma or systemic metastases of malignant tumors. The purpose of this study was to determine the optimal contrast-injection protocol for the whole body survey using MSCT. Material and methods: 120 patients were randomized into 4 equally sized groups of contrast material injection protocols: (1) injection rate 2.0 ml/s with a delay time 60 s, (2) injection rate 0.028 l/s × patient weight (kg) with a delay time 60 s, (3) injection rate 0.021 ml/s × patient weight with a delay time 80 s, (4) injection rate 0.035 ml/s during 40 s followed by injection rate 0.018 ml/s during 20 s with a delay time 70 s. Each patient received a volume of 1.7 ml/kg × patient weight (kg) Iopamidol 300 mg/ml. Multislice helical scans from the apices of the lungs to the base of the pelvic cavity were performed during one breathhold with 0.8 s rotation time, 5.0 mm detector collimation, and 6:1 pitch. The CT numbers of the thoracic and abdominal aorta, pulmonary artery, portal vein, superior and inferior vena cava (SVC, IVC), liver and pancreas were measured. In addition, two radiologists assessed the artefacts caused by contrast material in SVC and IVC visually, and graded them into three categories (1 = mild, 3 = strong). Results: Protocol 4 provided better enhancement of the liver and IVC with fewer artifacts in SVC than did the other protocols. Conclusion: Protocol 4 was suitable for the whole body survey using MSCT.

The effect of hyperosmolality, sodium ions and oubain preparation on iodinated contrast medium-induced potassium release from the human blood cells K. Hayakawa, T. Nakamura, Y. Shimizu; Kyoto/JP Purpose: Potassium release from blood cells is a contrast medium induced phenomenon. The purpose of the study is to assess the effect of hyperosmolality and sodium ions in the solution, and also the effect of the preparation of blood using oubain on the potassium release from human blood cells. Materials and methods: Fresh human blood was mixed with the test solution, in order to examine the temporal changes in the whole blood potassium levels and to calculate the potassium release rate. Test solutions included 5%, 20%, 50% glucose, glyceol, 0.9%, 10% NaCl, and 50% glucose mixed with various amount of sodium ions. The effect of blood preparation using oubain which is the strong inhibitor on Na-K ion pump function was evaluated with 50% glucose, 370 mg I/ml diatrizoate and 370 mg I/ml iopamidol. Result: The potassium release rates were dependent on the hyperosmolality of the test solution. The average potassium release rates and standard deviation were 7.3 ± 2.4 with 5% glucose, 13.5 ± 2.3 on 20% glucose, 128.4 ± 44.9 µmol/min on 50% gluocose. The solutions including sodium ions showed relatively low release rates. The addition with sodium ions into 50% glucose significantly decreased the potassium release rates. The preparation of oubain significantly decreased potassium release rates with 50% glucose and diatrizoate. Conclusion: Hyperosmolality promoted potassium release, but the presence of sodium ions in the hypertonic solution inhibited it. The depressant effect of oubain preparation may suggest that the potassium release from blood cells could be caused by the inhibitory effect on the Na-K pump on the blood cell membranes.

Diagnosis and follow-up of malignant liver tumors using ultrasound contrast agents (Levovist, Optison) and pulse inversion harmonic imaging (PIHI) Z. Jakab, Z. Harkanyi, L. Engloner, E. Csoregh, G. Szekely, Z. Tulasssay; Budapest/HU Purpose: Evaluate contrast-enhanced ultrasonography using pulse inversion harmonic imaging (PIHI) for diagnosing and monitoring of therapeutic efficacy in malignant liver tumors. Methods and materials: 17 patients with hepatic masses (histology: HCC n = 10, metastases n = 7) were examined after single bolus injection of a US contrast agent (Levovist or Optison). 12/17 patients underwent transcatheter arterial chemoembolisation, one further patient had additional percutaneous ethanol injection. 5/13 patients underwent PIHI before and after their treatment. Non-contrast 2D harmonic, color Doppler and contrast harmonic imaging were performed in all cases (ATL HDI 5000, 2 -5 MHz convex probe). Tumor vascularity was assessed with low MI and continuous PIHI. Liver parenchyma was examined with high MI with single sweep technique. Whole study was recorded on videotape. There was no evidence of side effect. All patients had multiphase helical CT, 10/17 also had MRI. Results: Enhancement of tumor vessels and liver parenchyma were seen in all cases. Subjective conspicuity was improved with PIHI. Additionally three, so far undetected lesions, were depicted with PIHI compared to non-contrast 2D imaging. Correlation between contrast enhanced PIHI and CT/MRI was observed (15/17). Conclusion: Contrast enhanced scans proved to be useful in assessing the therapeutic effect of treatment on malignant liver masses and guiding additional treatment in cases of partial response, when compared to conventional 2D and color Doppler imaging. Due to the good correlation between PIHI and CT/MRI in the detection of residual viable tumor, contrast enhanced PIHI may be able to replace CT/MRI in the follow-up of liver malignancies.

Results: There was no correlation between bolus geometry and age or weight. The threshold was reached after a mean trigger time of 20.8 s ± 5.01 in males and 16.3 s ± 3.93 in females. This proved to be a significant difference with regard to gender (p < 0.001). Also, there was a small correlation between the threshold interval and lung area at the left atrial level (r = 0.35). Conclusion: "Smart-prep" bolus triggering allows optimized enhancement of the organs, and the threshold interval is statistically different for genders.

MR arthrography: A proposal for solution optimization with lidocaine. An in vitro experience E. Genovese 1 , L. Callegari 2 , G. Angeretti 1 , P. Sosto 3 , C. Neri 1 , C. Fugazzola 1 ; 1 Varese/IT, 2 Milan/IT, 3 Pavia/IT Objective: MR arthrography is an invasive technique and pain during capsular distension may limit the examination feasibility. To overcome this limitation we added a local anesthetic (ie, lidocaine) to the contrast agent solution. We aimed at: (a) to assess Gadolinium DTPA solution with the best signal-to-noise ratio and to compare its results in different sequences; (b) to evaluate the effects of lidocaine on the physical characteristics of the solution, to measure the solution viscosity coefficient. Methods and material: The Gd-DTPA was diluted with saline and lidocaine at various concentrations. The viscosity coefficient of the solutions was analyzed with Mohr balance and Ostwald viscosimeter and finally compared with that of solutions containing an iodinated contrast agent. Signal intensity was measured with a 1.5 T superconductive MR unit with a dedicated head coil; we used T1weighted spin-echo and STIR sequences. Results: Viscosity is negligibly affected by lidocaine concentration changes when the paramagnetic contrast agent concentration is unmodified. Signal intensity is also unaffected by the variations of lidocaine concentration which does not interfere with the biphasic behavior of Gadolinium. Conclusions: The optimal signal-to-noise ratio in T1-weighted sequences is provided by 0.4 %. Lidocaine does not significantly influence the physical characteristics of the solution. The low viscosity of the paramagnetic contrast agent appears to favor quicker spread of the solution, even in tiny defects. Thanks to its anesthetic effect, lidocaine facilitates the examination in painful joints without affecting the diagnostic result.

Everything you always wanted to know about water-soluble X-ray iodinated contrast media, but were afraid to ask A.N. Chalazonitis, E. Nakahtsis, D. Koumarianos, S. Karabelas, P. Chronopoulos; Athens/GR Even though iodine was recognized very early as positive X-ray contrast media (CM), it still took more than 30 years for the development of the clinical acceptable CM to be used. In this exhibit we present a comprehensive and educational CD-ROM that includes also fundamentals of CM principles as well as essential guidelines for their optimum use in every day practice. Questions commonly asked concerning efficacy and safety of CM will be discussed. Structure, physicochemical properties, pharmacokinetics, tolerance, and influence of CM on different organ functions and vessels will be analyzed. Risk factors, precautions, side effects and reactions and their management will be presented in a question-answer designed model.

Miscellaneous C-0325 MRI in the assessment of testicular feminisation N. Kadi, J. Chopier, Y. Ait Amar, M. Bazot, J. Bigot; Paris/FR Purpose: Testicular feminization is a rare sex-linked androgen insensitivity disorder. We propose to determine the usefulness and the accuracy of pelvic MRI to localize the testes and describe the pelvic malformations. Surgery is usually performed on testes to prevent the malignant degeneration. Materials and methods: Two young women (17 and 27 years old) were evaluated for primary amenorrhea and both of them have a complete gynecologic examination, an endocrine evaluation, a karyotype and an imaging evaluation based on sonography and a pelvic MRI. Results: Clinically, the gynecologic examination revealed in both of them a rudimentary vagina and a female type external genitalia and biologically a high level of testosterone. No gonads (ovaries and testes) or uterus were identified in sonography and the kidneys were normal. MRI revealed in both of them a blind vagina and testes in inguinal area without uterus or ovaries. The diagnosis was confirmed by the karyotype (46 XY). Conclusion: MRI is the only exam which confirms the diagnosis in illustrating gynecological malformations and localize testes in Testicular Feminisation.

Purpose: To evaluate the utility of MRI urography in the detection of the ureteric obstruction level. Methods and materials: In a one-year period, 38 patient with ureterohydronephrosis was examinated on 1.5 T MR unit (Magnetom Symphony, Siemens). MRI urography (T2 tse cor thick slab and T2 haste cor thin slice) in combination with T1-and T2-weighted images were performed. Results: The following disorders were assessed: transitional cell carcinoma (8 cases), renal neoplasm (5), intraperitoneal and retroperitoneal neoplasm (3), inflammatory and infections process (7), ureteral stones (15). Level of obstruction in MRU and MRI was found in the same location: ureteropelvic (8), ureteric (19), and ureterovesical junction (11). Results were compared with those of IVU, US, helical CT and clinical outcome. Conclusion: The MRU and MRI provides an optimum view of the urinary tract. MRU is a non-invasive alternative to IVU in the detection of the ureteric obstruction level.

Complex US-technologies in the diagnostics of bladder tumors I. Nasnikova, V. Kozlov; Moscow/RU Purpose: To evaluate diagnostic efficacy of Doppler US-technologies in the diagnostics of bladder tumours. Materials and methods: 53 patients with bladder tumours underwent bladder US-examination on HDI 5000 (ATL Phillips), Voluson 530 DT and Power Vision-6000 (Toshiba) using grey-scale, Colour and Power Doppler, 3D Power Doppler. Verification of the diagnosis was done by excretory urography, cystocsopy with lesion's biopsy, cytological urine analyses, histo-morphologic analysis of the removed bladder lesions. Results: The sizes of bladder lesions varied from 0.5 cm to more with invasion of all bladder walls. TRUS of bladder tumours demonstrated safe visualization of small bladder tumours, which sizes were less than 1.5 cm in 11 (20.7 %) cases. Neoplasms were located in mucosa in 37 (69.8 %) patients, infiltrated muscular layer in 12 (22.6 %), invaded the perivesical space and prostate in 4 (7.6 %) patients. Tumours vascularization seemed avascular in 3 (5.7 %) cases with large necrosis and were hypovascular in 31 (58.5 %) and hypervascular with arterialvenous shunts in 19 (35.8 %) cases. 3D Power Doppler improved the accuracy and allowed detection of the whole network of small tumour vessels, that was especially actual in submucosal tumors. Transabdominal grey-scale US-examination had PPV 67 %, NPV 69 %, sensitivity 64 %, and specificity 63 %. Complex US-examination using TRUS with Doppler technologies was informative: PPV was 97 %, NPV 98 %, sensitivity 96 %, specificity 94 %. 

Doppler visualization of ureteric jets in unilateral hydronephrosis B. Brkljacic, A. Cvitkovic Kuzmic; Zagreb/HR Purpose: To evaluate color Doppler US (CDUS) visualization of ureteric jets in the assessment of unilateral hydronephrosis in children and adolescents. Materials and methods: CDUS was performed in 32 healthy children (control group) and 27 pts with hydronephrosis (age range 3 -21, mean 10.5 ± 4.4 a). Nine had acute renal colic due to ureteric calculus, seven had UPJ stenosis and eleven had non-obstructive, non-refluxive hydronephrosis. CDUS was used to visualize and analyze ureteric jets at vesicoureteric orifices. Jets were counted over 5%thinsp;min periods and jet-frequencies calculated for each ureteric orifice. US findings were correlated with IVU, VCUG and Tc-DTPA renography findings. Results: In controls jets were visible in 57/64 ureteric units (89 %), their mean frequency was 4.1 jets/min, and right-to-left differences were not statistically significant. In children with hydronephrosis jets were visible in 93 % of normal ureteric units, in 1/9 (11 %) of ureters with calculus, 2/7 (29 %) ureters with UPJ stenosis, and 8/11 (73 %) of ureters with non-obstructive hydronephrosis. The difference in jet frequencies between dilated and non-dilated kidney sides in pts with non-obstructive hydronephrosis is not statistically significant.

Conclusions: Absence of jets in patients with acute obstruction due to the ureteral calculus strongly correlates with high-grade obstruction. In UPJ stenosis absence of jets does not exclude significant obstruction, and in non-obstructive hydronephrosis jets are visible from majority of dilated units. CDUS cannot replace IVU or diuretic renography for diagnosis of obstruction, but could be used as adjunctive or screening method in unilateral hydronephrosis.

InCl combined with erythropoietin in vitro and in vivo Y. Nakagami, N. Takahashi, M. Ito, T. Ikegami, T. Nozawa, S. Matsubara, T. Inoue; Yokohama/JP Purpose: Last year, we reported that 111 InCl, which is used for bone marrow scintigraphy, might combine with erythropoietin. We thus studied this in vivo and in vitro in order to resolve the mechanism. Methods and materials: Over the last four years in our hospital we have used scintigraphy with 111 InCl to study 30 patients with aplastic anemia, myelofibrosis, MDS and PNH. Their blood tests were also reviewed. Furthermore, we performed western blotting using samples containing various concentrations of commercial erythropoietin. The membranes were mixed with 111 InCl and incubated at 37°C for 12 hours. Next, the membranes were mantled with X-ray film and exposed. Results: Bone marrow uptake was low, but 82 percent of the patients had high uptake levels in the kidneys. 84 percent of patients had high level concentrations of erythropoietin in their blood. In western blotting, the erythropoietin bands became clear, as concentrations were higher. Conclusion: The study in vitro showed that 111 InCl combined with erythropoietin, which is produced in the kidneys and flows into the blood. There were also patients who had received erythropoietin as medication, resulting in high level concentrations. Patients who had high level concentrations of erythropoietin in their blood accumulated a lot of erythropoietin in their kidneys. These results suggested that 111 InCl combined with erythropoietin in the kidneys resulting in the high levels of renal uptake of 111 InCl.

Various appearances of metastatic renal disease: A CT pictorial guide F. Sandomenico, A. Nunziata, O. Catalano, A. Siani; Naples/IT Purpose: Haematogenous metastatic disease to kidney is an uncommon but complex occurrence. A wide spectrum of helical CT changes can be encountered in clinical practice with various pitfalls and need for differential diagnosis. Exhibit content: Cases of renal metastasis from various sources: lymphoma, melanoma, pulmonary carcinoma, mammary carcinoma, pancreatic carcinoma, and contralateral renal tumour (synchronous or metachronous) are presented. Renal involvement may be uni-or bilateral, isolated or in association with a generalized tumour. The lesion maybe limited to the renal parenchyma, bulge externally, or be primarily located in the perirenal space. Attenuation and contrast-enhancement may vary. Normal renal structure can be progressively infiltrated and destroyed. Learning objectives: To illustrate the wide spectrum of helical CT appearances of metastatic renal disease.

Virtual cystoscopy: Correlation with conventional cystoscopy for new and recurrent carcinomas of the bladder R.F.J. Browne, S.M. Murphy, M. Butler, J. Thornhill, R. Grainger, T. McDermott, S. Hamilton; Dublin/IE Purpose: To evaluate the application of virtual CT cystoscopy in the detection of undiagnosed and recurrent bladder carcinomas and to correlate these findings with subsequent conventional cystoscopy. Methods: An initial prospective study was undertaken of 15 patients presenting with suspected new or recurrent bladder neoplasm. There were 12 males and 3 females with ages ranging from 47 to 83 years (median 67.5 years). Patients underwent virtual cystoscopy prior to conventional cystoscopy. Technique consisted of insertion of a 14 F Foley catheter and insufflation of 100 -500 ml air depending on patient tolerance. An AP scout view of the region was obtained prior to a single breath-hold helical CT scan (Toshiba XVision/GX)of the air filled bladder. A further scan was performed in the prone position. Volume-rendering algorithms allowed intraluminal views of the bladder to be generated and interactive scroll through the virtual bladder could be undertaken. Examinations were read by one consultant radiologist blinded to conventional cystoscopy findings. Results: Virtual cystoscopy detected tumour in all 15 patients and correlated well with findings at conventional cystoscopy. Virtual cystoscopy accurately detected all superficial tumour recurrances. In combination with axial images of the air-filled bladder invasion of tumour through the bladder wall could be detected. In addition, virtual cystoscopy detected a number of bladder diverticulae not seen on conventional studies. Conclusion: Virtual cystoscopy can accurately detect intrinsic bladder neoplasms, including superficial tumour recurrence. It can also detect and assess bladder diverticulae. This may represent a non-invasive bladder imaging technique, especially in patients attending for check cystoscopy for recurrent bladder tumour.

Bladder tumour detection using MR virtual cystoscopy A. Urbanik, Z. Dobrowolski, R. Chrzan, T. Popiela, T. Drewniak, W. Lipczynski; Krakow/PL Introduction and Objects: The aim of the study is to present our experience on MR virtual cystoscopy. Material and methods: 26 patients were subjected to uretherocystoscopy. All these patients were examined using SIGNA Horizon 1.5 T MR System (GEMS). The obtained images were transferred to the workstation for further processing by the software (3D and Navigator, GEMS). T1 and T2-weighted transverse cross-sections, 3D reconstructions, as well as static and dynamic virtual cystoscopy images were obtained. The results of the MR diagnostic procedures including virtual cystoscopy images were compared to the traditional cystoscopy findings. Results: The analysis of the MR scans of urinary bladder confirmed the presence of tumours in all cases. Their localisation, number, and extent were evaluated. MR findings were correlated with those of the traditional cystoscopy. Conclusions: Due to their high-resolution MR images of the urinary bladder allow very precise assessment of urinary bladder pathologies. Virtual cystoscopy provides image of the urinary bladder without using endoscopy, ionising radiation or contrast media. The method of MR virtual endoscopy is completely non-invasive and may be used for visualising urinary bladder cavity in cases where the traditional cystoscopy is contraindicated. In addition, MR is the most accurate current method of assessing urinary bladder wall infiltration.

A comparison of the diagnostic accuracy and efficacy of magnetic resonance urography (MRU) versus intravenous urography (IVU) in a diabetic population R.R. Misra, C. Allen; London/GB Purpose: Magnetic resonance urography (MRU) is a new technique. In around 30 minutes, MRU provides angiographic, parenchymal and collecting system information with no radiation burden. It has been shown to be of value in demonstrating dilated renal tracts in children and in pregnancy. Its benefit in diabetic patients is unknown. This latter group is known to have a high incidence of renal disease and may develop nephrotoxicity from iodinated contrast medium. Hence the diagnostic accuracy and efficacy of MRU versus IVU in diabetics was investigated. Materials and methods: All diabetic patients referred for an IVU were recruited into the study. IVU Protocol: Routine sequence after 70 ml Omnipaque 350. MRI Protocol: 1.5 T Phillips Scanner, 20 ml intravenous gadolinium. Angiogram: Contrast enhanced MRA -3D FISP sequence. Parenchymal: T1 weighted axial and coronal images obtained both pre and post Gd. MRU: 3D FISP images acquired 5 C A B D E F 404 Genitourinary and 15 minutes post Gd. Small and large FOV images maximise PC system detail. No compression applied but all patients were given 20 mg IV Frusemide at the onset. Maximum intensity projections (MIP's) of the MRA and MRU sequences were viewed on a workstation, and compared with the IVU. Results: PC system abnormalities were demonstrated on MRU in concordance with IVU findings in all cases, although calculi poorly imaged. MRU is additionally able to identify renal artery stenosis and parenchymal masses Conclusion: MRU provides 'three tier' diagnostic information, although renal tract calculi are sub-optimally imaged. We advocate the use of MRU in routine practice.

CT evaluation of adrenal gland thickness in preclinical cushing's syndrome M. Higuchi 1 , N. Nishii 1 , F. Sakai 2 , M. Naruse 2 ; 1 Saitama/JP, 2 Tokyo/JP Purpose: Adrenal adenomas showing autonomous cortisol secretion without specific endocrine symptoms are sometimes discovered in patients with adrenal incidentalomas. In this condition, described as preclinical Cushing's syndrome (preCS), basal plasma cortisol levels are normal and further endocrinological examination is necessary to distinguish non-functioning adenoma. Our aim was to determine whether CT finding of the atrophic adrenal gland are predictive of preclinical Cushing's syndrome in patients with clinically silent adrenal incidentaloma. Methods and materials: Adrenal CT images of twelve endocrinologically diagnosed preCS patients were retrospectively reviewed. Two radiologists blinded to the endocrinological data analysed the adrenal glands at the contralateral side of the adenomas for thickness (normal, slightly thin, atrophic). Patients aged from 38 to 74 a (mean = 59), four males and eight females were included. All patients underwent measurement of plasma cortisol, ACTH, and DHEA-S levels, and the dexamethazone suppression test (1 mg, 8 mg), and CRH stimulation test. Adrenal scintigraphy was performed in nine patients. Results: Plasma ACTH levels were suppressed in seven of the twelve patients and were normal in five. The adrenal glands were atrophic in six, slightly thin in one patient with lower ACTH levels, and normal in four and slightly thin in one with normal ACTH levels. Conclusion: Adrenal incidentaloma with apparently atrophic adrenal parenchyma on CT may suggest preCS and, at least, measurement of plasma ACTH levels is required. However, preCS with normal ACTH levels cannot be differentiated from non-functioning adenoma unless further endocrinological analysis is performed.

CT staging of bladder carcinoma: Correlation with pathologic findings D. Negru, D. Ghiorghiu, S. Ghiorghiu, I. Negru, C. Daniil; Iasi/RO Purpose: To evaluate the accuracy of CT imaging in the staging of bladder carcinoma and to determine the usefulness of CT in the evaluation of the degree of tumour extension through the bladder wall. Methods and materials: 62 patients aged 32 -86 year, median age 62, with a histopathological diagnosis of bladder carcinoma underwent preoperative CT examination between January 1996 and December 2000. Examinations were done without contrast medium followed by two series of images after intravenous contrast medium injection (370 mg I/ml, 100 ml, 2 ml/s). Surgery was performed in 54 patients. The CT findings were correlated with surgical and pathological results. Results: Extension to perivesical fat -T3 stage -was present in 13 of 54 (24.07 %) patients. Stage T3 tumour was accurately depicted by CT in only 5 of 13 (38.46 %) cases because the actual T3a stage, microscopic invasion of perivesical fat, cannot be depicted by CT exam. Invasion of the adjacent organs -T4 stage -was present in 15 of 54 (27.77 %) patients. CT demonstrated adjacent organs invasion in 12 of 15 (80 %) cases. On the basis of CT findings, the tumour was correctly staged, according to the TNM classification (AJCC 1997) , in 45 to 54 (83.33 %) patients, tumour extension was overestimated in 6 of 54 (11.11 %) patients and was underestimated in 3 of 54 (5.55 %) patients. Conclusion: CT examination is a powerful investigation for the preoperative staging of bladder cancer.

The correlation of clinical manifestations and radiological appearance of metastatic calcifications in patients undergoing dialysis A. Christopoulos, P. Andrikacos, C. Triga, P.A. Dimopoulos; Patras/GR Introduction: In uremic patients, hyperphosphatemia and low renal production of calcitriol produce a decreased level of ionised calcium. This continuous stimulation results to enlargement, of parathyroid glands. Even though the skeletal mani-festations are known complications of this disorder, there still exist many unanswered questions, about the consequence and the clinical importance of the calcific deposits in the rest of the body. Purpose: To study the incidence of metastatic calcifications in patients on regular hemodialysis, to describe the preferable sites of their deposition and to correlate them with any relevant clinical manifestations. Materials and methods: 52 hemodialysed patients in a renal unit, (46 -83 a, m.age 58) underwent clinical and laboratory (PTH, CaXP) follow-up. Those with clinical and or laboratory evidence of secondary hyperthyroidism underwent Ultrasonography and thallium/technetium isotope scanning of the parathyroid glands, and almost their whole body was scanned with CT in order to detect any disseminated calcifications. Results: In 13 patients the diagnosis of secondary hyperparathyroidism was established (21 %). Clinical manifestations: bone pain, arthralgias, thirst, nausea, vomiting, constipation, hypertension, muscle weakness, easy fatigability, paresthesias, cough, exercise dyspnea. Localization of calcifications: skin, soft tissue, periarticular, pleura, pericardium, tracheabronchial tree, visceral organs, coronary arteries, cardiac valves, blood vessels, ocular tissue, brain. Conclusion: Despite the common belief that most patients are asymptomatic and calcifylaxis is a rare situation, the detailed follow-up indicated that clinical manifestations were well correlated with the localization and the extent of the calcifications. 

We retrospectively evaluated the CT and MR imaging findings in ten patients with retroperitoneal neural sheath tumours (seven schwannomas and three neurofibromas). CT scans were available in eight patients and MR images in one. In one patient, both CT and MR imaging were performed. Results: The schwannomas were located in the retroperitoneum adjacent to the kidney in six patients and in the presacral pelvic retroperitoneum in one. The maximal diameters of the schwannomas were 6 -10 cm. Imaging findings of shwannomas were well-demarcated, mainly cystic masses in five and mainly solid masses with internal small cystic areas in two patients. Peripheral rim calcifications were noted in five, and spotty nodular calcifications in one. The neurofibromas were located in the left iliac fossa, rectovesical pouch, and mesenteric root. The maximal diameters of the neurofibromas were 6 -13 cm. Imaging findings of neurofibromas were well-demarcated, solid enhancing masses with multifocal low attenuation areas, representing myxoid changes. Conclusion: Retroperitoneal neural sheath tumours were presented as well-defined, large masses with characteristic locations. The schwannomas frequently showed large area of cystic degeneration, while the neurofibromas were mainly solid masses with small foci of myxoid degeneration.

Usefulness of magnetic resonance urography in patients with pelvic tumours D. Werel, E. Tarasow, T. Werel, M. Jozwik, J. Walecki; Bialystok/PL Purpose: To evaluate the clinical utility of Magnetic Resonance Urography (MRU) in females with pelvic tumours in whom classical MRI was performed. Methods and materials: 14 women at the age of 36 -64 with pelvic tumours (10 cervical carcinoma, 4 ovarian tumours) were evaluated. In all patients previous ultrasound examination revealed unilateral or bilateral upper urinary tract dilatation. For assessment of local tumour staging, classical MRI was performed. Additionally we made MRU to visualise dilated urinary tract. The examinations were carried out on 1.5 T system (Picker Eclipse) using the flex coil. The MRU was based on Express FATSAT sequence (TE 240, TR 8000, FOV 37, matrix 384 × 512, FA 90°). Results: In all patients the depiction of urinary tract morphology was good. MRU was able to determination a grade of urinary tract dilatation (small 3, moderate 6, big 5), site of obstruction and unilateral (8 cases) or bilateral (6 cases) localisation of hydronephrosis in all patients. Conclusions: MR urography is simple and fast method in evaluation of hydronephrosis and determination of the level of obstruction. Combining classical MRI with MRU allows better evaluation of local tumour staging and cause of urinary tract obstruction. The results can influence further therapeutical approach (nephrostomy or catheter indwelling). Our results show that application of MRU can replace intravenous urography and shorten diagnostic procedures. Purpose: To evaluate the feasibility and the advantages of Multi-Slice CT-pyelography in alternative to intravenous pyelography to detect obstructive pathologies and congenital malformations of the urinary tract. Materials: Different protocols were performed according to the clinical condition of the patient. Intravenous contrast media was administrated only if urinary tract dilation or haematuria was present. Patients underwent Multi-Slice CT (Lightspeed GE) with 3D Volume Rendering reconstruction using a Vitrea workstation (Vital Images). Parameters were as follows: thickness 5 mm, reconstructed to 5 mm, 15 HS. Scans were performed without contrast agent, then during intravenous injection (3 ml/s, start delay 50 s) of contrast material and 15 minutes after the injection. If renal artery disease was suspected an early arterial phase was obtained (delay 25 s). All the images were reconstructed at 2.5 mm thickness and 1.25 interval. Reformatted images in sagittal and coronal planes were mandatory in order to modify slab thickness to obtain a MIP of the excretory system simulating pyelography aspect. Results: Congenital malformations were easily depicted allowing precise visualisation of the urinary tract and vascular pattern; small urinary stones were precisely located into urinary tract. Small urothelial lesions were difficult to be seen, especially those in distal calices. Conclusions: Multislice-CT with or without contrast agent, with volume rendering reconstruction can easily detect small kidney or urinary tract stones and congenital malformations. CT can give additional information about vessel anatomy and structures around the urinary tract. CT is still not so trustworthy for small urothelial lesions.

Adverse impact of nutcracker-phenomenon on outcomes after varicocele repair demonstrated by colour Doppler ultrasound L. Pallwein, A. Klauser, G. Pinggera, A.H. Schuster, G. Feuchtner, D. zur Nedden, F. Frauscher; Innsbruck/AT Objective: To assess the impact of the nutcracker ("left renal vein entrapment") phenomenon in patients undergoing surgical repair of varicoceles using colour Doppler ultrasound (CDUS) Materials and methods: 84 men (mean age: 23 ± 9 years) demonstrated varicoceles on CDUS (76 left-sided; 8 bilateral), which were diagnosed on the basis of a venous diameter of 3 mm or more and increased venous retrograde flow in the pampiniform plexus in the supine position during Valsalva manoeuvre or when changing from the supine to upright position. For diagnosing nutcracker phenomenon we used following criteria: anteroposterior (AP) diameter > 1 cm and peak velocity (PV) < 15 cm/s of the left renal vein (LRV) at the hilar portion and AP diameter 110 cm/s (ratio of PV > 5) of the LRV between the aorta and the superior mesenteric artery. After surgical repair we compared the presence of nutcrackerphenomenon with the frequency of varicocele recurrence. Results: 14 of 84 (17 %) demonstrated a nutcracker-phenomenon. All of those showed a left-sided varicocele. Postoperatively (mean follow-up: 23 ± 8 months) 25 of 84 patients (30 %) showed a varicocele recurrence, including the 14 patients with nutcracker-phenomenon. The rate for recurrence was statistically significant greater in those with nutcracker-phenomenon (p < 0.001, Fisher's exact test). Interestingly 2 of the 8 patients (20 %) with bilateral varicoceles showed recurrence only on the right side.

The presence of the nutcracker-phenomenon resulted in a significantly higher rate of varicocele recurrence. Patients presenting with varicoceles should routinely be evaluated for the presence of nutcracker-phenomenon before surgical repair.

The role of dynamic MRI in the evaluation of adrenal masses K. Vanderdood 1 , B.J. Op de Beeck 2 , M. De Maeseneer 1 , M. Osteaux 1 ; 1 Brussels/BE, 2 Antwerp/BE Purpose: To demonstrate the use and importance dynamic MRI in the detection and characterisation of adrenal masses. Material and methods: 38 patients with suspected adrenal masses on helical CTscan or US underwent MRI on a 1.5 T system using transverse T2-weighted HASTE, T1-weighted GRE with and without fat suppression and T1-weighted opposed phase GRE. In 30 patients T1-weighted GRE images were obtained immediately after intravenous gadolinium administration (2 cm 3 /s) and a rapid saline flush. The sequence was repeated 30 s and 90 s post contrast. Two independent readers evalu-ated morphology, dimensions, tissue signal characteristics and contrast enhancement patterns of the adrenal nodules and compared the data with the CT or US findings if available. Results: 42 masses were found including adenoma (n = 28), metastasis (n = 6), adrenocortical carcinoma (n = 2), myelolipoma (n = 2), pheochromocytoma (n = 1), ganglioneuroma (n = 1), abcess (n = 1) and one pseudolesion (gastric diverticulum). When CT-scan was equivocal (n = 21), MRI remained inconclusive in 12 cases without intravenous gadolinium injection. After contrast administration, a clear diagnosis could be made in all these cases. Except for adenoma, contrast injection was required for the differentiation of malignant from benign lesions. Conclusion: Dynamic MRI should be included in the examination protocol in the initial assessment of adrenal nodules enabling lesion characterization. MRI including dynamic contrast examination demonstrated higher specificity compared to CT. To determine whether 3D TVS provide additional diagnostic information over 2D TVS in assessment of uterine cavity pathology in the cases of abnormal uterine bleeding. Method and materials: We have evaluated 74 patients that were referred to the emergency room due to the uterine bleeding. All pts were initially examined with 2D TVS and then 3D TVS data was acquired. Multiplanar images were created and 3D volume rendering was performed. 2 radiologists experienced in 3D technique blinded to pts history evaluated first conventional 2D images and then resliced coronal 2D images and volume rendered 3D cineloops. US results were compared with hysteroscopy and final histopathology. Results: Both methods were accurate in detection of the presence of a uterine abnormality. 3D TVS provided better orientation and precise evaluation of the uterine cavity than 2D TVS. 3D TVS results correlated with hysteroscopy in 95 % of cases compared to 67 % of 2D TVS data. 3D coronal images clearly showed triangular shape of the uterine cavity and allowed better location of the intracavitary abnormalities (fibroids, IUD defragmentation, endometrial hyperplasia, polyps, endometrial cancer, residual trophoblastic tissue, postabortion blood clots). Image reconstruction on coronal planes by 3D TVS improves determination of submucous fibroids, polyps, and residual trophoblastic tissue. Conclusions: 3D TVS may be useful as a complement to 2D TVS, which may increase diagnostic confidence in detection and depiction of the anatomical location of uterine cavity abnormalities.

The role of MR imaging in gynecologic emergencies M. Nishino, K. Hayakawa, K. Iwasaku, T. Shimada, K. Takasu; Kyoto/JP Purpose: To describe characteristic MR findings in the variety of acute gynecologic diseases, and to demonstrate the significance of MR imaging in gynecologic emergencies. Methods and materials: Pelvic MR imaging studies conducted in the acute gynecologic conditions were reviewed and correlated with surgical and pathological findings. The cases of ovarian hemorrhage, ectopic pregnancy, pelvic inflammatory diseases such as Fits-Hugh-Curtis syndrome and tubo-ovarian abscess, torsion and rupture of ovarian tumors were included in this review. Results: MR imaging was sensitive in detecting hemorrhage in patients with suspicion of ectopic pregnancy and ovarian hemorrhage. In cases of ectopic pregnancy, MR imaging precisely visualized the location of hemorrhagic gestational sacs. The cases of ovarian hemorrhage were also accurately diagnosed by MR imaging. In addition, the detailed anatomical information enabled to determine the cause of hemorrhage, such as rupture of corpus luteum or hemorrhage from corpus luteum cyst. In cases of ovarian tumors accompanying hemorrhage, rupture or torsion, MR imaging studies were useful not only in revealing these complications, but also in predicting pathological tumor types preoperatively. MR manifestations in pelvic inflammatory diseases varied from strong enhancement of the parametrium to a pus-filled tubo-ovarian abscess, according to the degree of inflammation. Conclusion: MR imaging studies provided clinically significant information in the variety of acute gynecologic diseases. MR imaging was of great value for making accurate diagnosis and determining proper treatments in gynecologic emergencies.

Transvaginal ultrasound examination of pelvic varices in women with chronic pelvic pain L. Jvarsheishvili, D. Gachechiladze; Tbilisi/GE Purpose: To examine the pelvic varices (PV) as a cause of chronic pelvic pain, to illustrate the various appearance of PV, their pattern on transvaginal colour Doppler (TVCD), to define the degree of PV based on diameter and location of varicosis.

Materials and methods: 126 women (aged 22 to 53 years) with long-term pelvic pain underwent TVCD. The primary type of PV was revealed in 27 (21.4 %) patients, in other cases PV were secondary caused by the organic pathologies (endometrioses, pelvic inflammatory disease, leiomyoma). Results: The main variant of the PV (37 %) was presented as long tubar retort-like structures. The spilled type (33 %) has the shape of cellular spongy non-echogenic multiple formation. In cases of total PV (30 %) these two appearances of varicosis are visualised together. We defined three degrees of PV: (I) the dilation to 5 mm for all pelvic vein plexus. (II) the dilation 6 -10 mm and (III) the dilation above 10 mm in cases of total varicosis or main varicosis of uterovaginal plexus. The severity of pains was mostly correlated with degree of PV. Conclusion: Women with long-term pelvic pains show various degree of PV. The severity of pains is related to degree of PV. TVCD has a high diagnostic value for visualisation and characterisation of PV.

The role of colour Doppler sonography in the monitoring of combined radiation therapy of the endometrium cancer L.L. Tyeryayeva, T.V. Kozarenko, L.Y. Lyevkovskaya; Kiev/UA Purpose: The choice of the method for objective evaluation of the efficacy of the combined therapy in patients with inoperable endometrial cancer (EC) is one of the actual problems in oncogynecology. The purpose of this study was to evaluate the role of Colour Doppler sonography in monitoring of the endometrial cancer response during combined radiation therapy. Methods and materials: 68 patients with EC were examined using complex sonography ("Elegra" Siemens) with transvaginal probe 6.0 MHz before combined radiation therapy. Colour Doppler sonography was performed in all patients before treatment, after first stage of the distant radiation therapy, after complete course of combined radiation therapy and 3 months after the treatment. Results: The main features of the total regression of EC were: the reduction of the uterus size and of the endometrial thickness to normal for age, and the return to its normal echo-structure. RI in the arcuate arteries was 0.72 ± 0.71. Indication of partial regression of the neoplastic process were the reduction of the uterus size and the endometrial thickness of more than 50 % comparing with the initial data; the homogenisation of its echo-structure; the reduction of the invasion depth of the neoplastic process into the myometrium. RI in the arcuate arteries was 0.59 ± 0.54. Conclusion: These sonographic criteria of the regression or progression degree of neoplastic process can be successfully introduced in the monitoring of the combined radiation therapy in patients with emdometrial cancer.

Colour Doppler sonography and MRI in gestational trophoblastic disease T.V. Kozarenko, V.E. Medvedev, V.A. Rogozhyn, L.V. Vorobjeva, L.L. Tyeryayeva; Kiev/UA Purpose: According to the data of the Institute of Oncology (Academy of Medical Sciences of Ukraine) the morbidity of women with choriocarcinoma in Ukraine has increased by 1.5 -1.7 times since 1993 and at present is 1:20000 -1:50000 of pregnancies. The purpose of this study was to evaluate the diagnostic possibilities of Colour Doppler sonography and MRI in women with verified choriocarcinoma. Materials and methods: 21 female patients (15 -45 a) with verified diagnosis of choriocarcinoma were examined with Color Doppler sonography and MRI. The investigation was performed, using "Elegra" unit with 6.0 MHz probe and 1.5 Magnetom-Vision-Plus-System (Siemens). Results: Transvaginal Colour Doppler sonography and MRI demonstrated enlargement of the uterus. Nodes (10 -53 mm) of inhomogenous structure without clear contours and cystic cavities were observed in myometrium. According to Colour Doppler sonography data, blood flow of low resistance was revealed inside choriocarcinoma node: RI 0.25 -0.57; PI 0.3 -0.7 and PSV more than 96 cm/s. These findings confirmed the presence of arteriovenous shunts. MRI displayed hypervascular choriocarcinoma nodes of heterogenic structure representing haemorrhages and shunts within them. The uterine arteries were dilated more at the side of the lesion. Materials and methods: This is a prospective study of 21 female patients (average age 28.8, range 16 -41) clinically suspected of having ectopic pregnancy. Pregnancy tests were positive and intrauterine pregnancies were excluded with sonography in all patients. MRI (1.5 T, Siemens, Vision) was performed with a body-array coil. We looked for an abnormal mass in T2-WI (HASTE) and T1-WI (2D FLASH) images, and then applied T2*-WI (2D FLASH) aiming at the mass. Remarkably low signal areas on T2*WI was diagnostic for ectopic pregnancy. Results: All 16 cases that we diagnosed as ectopic pregnancy underwent tubectomy and the diagnosis was confirmed. 5 cases were diagnosed as negative according to the criterion mentioned above; no mass in 2/5, no low signal area in the masses with T2*-WI in 3/5. Ectopic pregnancy was excludedd in 4/5, 3 were followed expectantly and 1 was underwent diagnostic laparoscopy. 1/5 underwent tubectomy for ectopic pregnancy that presented without bleeding and had not been aborted. The overall result of MRI in the diagnosis of ectopic pregnancy using T2*-WI as a key diagnostic factor was as follows; sensitivity: 94 %, specificity: 100 %, accuracy: 95 %. Conclusion: MRI using T2*-WI is a sensitive, specific, and accurate method in the evaluation of ectopic pregnancy. We emphasize the efficacy of T2*-WI that contributes to the high accuracy of our method, which is particularly sensitive for diagnosis of fresh hematoma.

Value of sonohysterography in patients treated with Tamoxifen I. Mourey, E. Bigot, G. Janaud, P.A. Grenier; Paris/FR Purpose: To assess the efficacy of sonohysterography (SHG) in the evaluation of the endometrium and uterine cavity in patients treated with Tamoxifen. Methods and materials: We retrospectively studied 43 women (aged 35 -81) before and during treatment with Tamoxifen. Preliminary transvaginal sonography (TVS) was performed prior to SHG (Hitachi EUB 40 or Acuson 128 XP). Sterile saline solution was instilled through a 5.3 Fr uterine catheter Cook or an intra uterine catheter Rudigoz with the use of TVS control. Sonohysterography was performed before and one year after the onset of the treatment by 25 patients and by 18 after 2 years; 9 patients had additional follow-up examinations obtained at 6 months.

After one year, we found significant modifications of the endometrial cavity in 17 women (68 %), including endometrial hypertrophy (n = 14) and polypoid lesions (n = 3). After 2 years, we observed an increase of the thickness of the endometrium and of the size of the polyps (means: 6 mm on the first exam and 20 mm on the last) and three new polypoid lesions were detected. Conclusion: The use of SHG increases the capability of TVS to differentiate between intracavity, endometrial and submucosal abnormalities. It could assume a minimally invasive way to the follow up of the endometrium in patients receiving Tamoxifen.

The role of transvaginal ultrasonography in non-gynecologic pelvic conditions M.D. Serrano, T. Ripollés, M.J. Martínez, L. Simó, A. Ruiz; Valencia/ES Purpose: To describe the spectrum of non-gynecologic applications of transvaginal ultrasonography (TVUS). Methods and materials: 38 patients with different pathologic conditions located deeply in the pelvis including rectal (n = 11) or lower sigmoid colon (n = 7) neoplasms, sigmoid diverticulitis (n = 7), pelvic appendicitis (n = 2), gut cysts (n = 2), peritoneal implants (n = 5), Crohn's disease (n = 2) and ureteral lithiasis (n = 2), were evaluated with TVUS. We compared the results with other imaging techniques like abdominal ultrasonography (US), computed tomography (CT) or barium enema. Results: TVUS is useful: (a) to assess rectal strictures or lower sigmoid colon neoplasms that are inaccessible to transrectal sonography, with similar results in preoperative staging to CT; (b) to distinguish the neoplastic or inflammatory (diverticulitis) nature of lower sigmoid colon strictures not determined by transabdominal or transrectal sonography and CT; (c) to assess rectal and perianal complications of Crohn's disease; (d) to diagnose pelvic appendicitis or diverticulitis, in addition to transabdominal sonography; (e) to characterize peritoneal malignant implants and (f) to detect lithiasis or tumours in the distal ureter. Conclusion: TVUS is a complementary technique to the abdominal or transrectal ultrasonography studies in the assessment of non-gynecologic pathology (i.e.: lower intestinal tract, urinary system and peritoneal cavity diseases).

MR features of malignant ovarian neoplasms arising from endometriotic cysts M. Kataoka, K. Togashi, T. Yamaoka, T. Koyama, S. Fujii, J. Konishi; Kyoto/JP Purpose: To demonstrate characteristic MR appearance of malignant ovarian tumors arising from endometriotic cysts. Materials and methods: MR images of 14 patients with malignant ovarian neoplasms (12 with clear cell carcinoma and 2 with endometrioid carcinoma) pathologically proved to be arising from endometriotic cysts were retrospectively reviewed. Comparisons with previous MR images (before the development of carcinoma) were made in three of the patients. Two readers evaluated MR images with consensus interpretation. Results: Both clear cell carcinoma and endometrial carcinoma arising from endometriotic cysts were unilocular or paucilocular cystic tumours (n = 13). The maximum diameter of the tumours ranged from 4 cm to 15 cm (mean 10 cm). Signal intensity of cystic portion was relatively high on T1-weighted image (n = 10), and high on T2-weighted image (n = 12). All of the tumours had mural nodules. Intensity of mural nodules was as low as that of myometrium on T1-weighted images (n = 11) and the same as or higher than that of myometrium on T2-weighted image (n = 12). These nodules were well enhanced on post-contrast images. In follow-up cases (n = 3), remarkable enlargement of cystic portion (diameter increased 5.7 cm in average) as well as emergence of mural nodules were observed upon development of carcinoma Conclusion: In following up patients with endometriotic cysts, enlargement of the lesion and presence of mural nodules should be carefully evaluated, as both were commonly observed in malignant ovarian neoplasms arising from endometriotic cysts.

Use of MR in the conservative planning surgery of uterine myoma M. Recio, V. Martínez de Vega, M. López-Pino, J. Montoya, M. Jiménez, J. Viaño, C. Peláez; Madrid/ES Purpose: MR is increasingly used for conservative planning surgery of the uterine myoma (myomectomy). MR offering a multiplannar imaging and tissue differentiation is a useful method in the preoperative evaluation of these lesions. It gives the necessary the information about location, size and relation with the endometrial cavity. The aim of this work is to describe the appearances of the uterine MR studies in order to plan surgery Material and methods: 165 patients were examined with previous sonographic diagnosis of myoma. MR studies were performed in a 1.5 T MR with a phased array coil using T1 SE, fat suppressed T2 FSE sequences, and gadolinium enhanced 3D EFGRE. 85 patients underwent myomectomy Results: 95 % of the lesions were hypointense in T2 sequences and there was a clear difference between the signal intensity of myoma, myometrium and endometrial lumcavity; 5 % of the cases (hystological leiomyomas) were isointense in T2 sequences and gadolinium enhanced sequences showed the margins of the lesions and their relation with the endometrial lumen. There was a great correlation with the MR information and the postoperative findings (macroscopic dimensions and the relation with the endometrial lumen). Discussion and conclusion: MR is the method of choice in the planning of conservative surgery of myoma, providing the exact information about location, size and relation with the endometrial cavity. The use of contrast enhanced imaging is only useful when the lesions are isointense with the myometral wall.

MRI pictorial essay of congenital Müllerian duct anomalies B.J. Op de Beeck 1, 2 , R. Salgado 1 , E. Schepens 1 , F. De Ridder 2 , J.J. Amy 2 , A.M.A. De Schepper 1 ; 1 Edegem/BE, 2 Brussels/BE Ultrasound, hysterosalpingography and laparoscopy or surgery have until now been the mainstays for the diagnosis of Müllerian duct anomalies (MDAs). All of these modalities have inherent limitations. MRI has been shown to be an accurate and non-invasive method for the evaluation of MDAs. MRI is also helpful in elucidating the etiology of obstructed MDAs and is particularly useful in patients in whom surgical unification is anticipated. The purpose of this poster is to present a pictorial review of typical MDAs diagnosed on MRI in order to highlight its role and to encourage its widespread use. Included in this are examples of segmental agenesis or hypoplasia, unicornuate uterus, didelphys uterus, bicornuate and septate uterus. MDAs are clinically relevant because they are associated with an increased incidence of impaired fertility and menstrual disorders. Associated renal anomalies will also be demonstrated.

Dynamic magnetic resonance imaging for evaluating the female pelvic floor F. Idoate, P. Alejandre, T. Fernandez-Villa, J. Aldave, J. Lorente, J. Indave; Pamplona/ES Purpose: To assess the feasibility of dynamic MRI for evaluating the prolapse of the pelvic organs in symptomatic women. Methods: 12 women with signs and symptoms suggesting pelvic prolapse underwent dynamic MR imaging at our institution using a 1 T magnet. The examinations were performed in the decubitus position with full bladder but no other preexamination preparation. Three patients were evaluated before and after surgical repair. The following sequences were used: axial and sagital T2 weighted TSE to asses midsagital plane and incidental pathological entities; midsagittal, parasagittal and axial True-FISP and T2-HASTE sequences were acquired at rest, during pelvic floor contraction, straining and miction (dynamic MRI). Parameters recorded included the posterior urethrovesical angle, bladder neck position and the vertical distances between pubococcigeal line and bladder base, cervix and anorectal junction. Dynamic MRI procedures were evaluated at cine-loop presentation. Results: Total room time was 20 minutes. All examinations were well tolerated. Dynamic MRI was able to depict the extent and interaction of the pelvic floor organs in all cases. Incidental pelvic pathologic features were observed in seven patients, including uterine fibroids, hydrosalpynx, ovarian cyst, nabothian and Bartholini cysts. All the patients presented prolapse at multiple sites. Eight cystoceles, five uterine prolapses, one vaginal vault prolapse, one post-surgical enterocele and eight proctoceles were revealed. The posterior urethrovesical angle was more than 110° in 12 patients. No descent of bladder base was recorded after surgical repair. Conclusions: Dynamic MRI is a rapid, noninvasive technique to evaluate pelvic floor descend, allowing objective postsurgical follow up.

Reflux into Cowper's glands on urethrography P. Kovacic 1 , D. Babnik-Peskar 2 , N. Majcen 3 ; 1 Slovenj Gradec/SI, 2 Ljubljana/SI, 3 Ptuj/SI Introduction: The Cowper's bulbourethral (BU) glands are one of the three major accessory sex glands with endocrine function in man and are involved in the immune defence and fertility. The pathology of the glands is rare and can be an incidental finding on urethrography or US. Clinical symptoms are non-specific. Sonographic appearance varies from normal to cystic dilatated BU ducts and/or BU glands. On urethrography outside impressions could be present, but occasionally contrast opacification is possible because of the reflux. Reflux shouldn't be mistaken for diverticulum, incomplete duplication of urethra, fistulous path, extravasation or false route.

In this retrospective study we evaluated radiographic signs of BU glands pathology, reflux and coexisting urethral pathology in all patients with retrograde urethrographies performed in 1996 (126) and 2000 (121). Results: Six (4.8 %) patients in 1996 (age 36 to 77 a) and 6 (4.9 %) patients in year 2000 (age 19 to 84 a) had reflux into BU glands. Associated pathology included: perineal trauma (1), surgical trauma (1), urethral strictures (7), tumour (1), postvoiding dribbling (1) and/or infections. Conclusion: Reflux into Cowper's glands on urethrograpy in our patients is comparable to the rate of BU pathology found in literature and showed significant correlation with urethral pathology. We presume, that reflux into BU glands should be considered as a consequence of other urethral pathology, and therefore important to diagnose.

Post-therapy CT follow-up in ovarian cancer D. Ghiorghiu, D. Negru, S. Ghiorghiu, L. Moisii, C.N. Ursulescu, M. Grigoras, C. Daniil; Iasi/RO Purpose: To determine the accuracy of computed tomography (CT) in the follow-up of the patients with ovarian cancer and to evaluate the correlation between CT findings and the values of tumour markers (CA 125). Methods and materials: Forty-two patients, aged 29 -73 years, median age 53 years, with a histopathological diagnosis of ovarian cancer underwent pre-and post-therapy CT examination between January 1997 and December 2000. Examinations were done with and without contrast medium (370 mg I/ml, 100 ml). Follow-up protocol included physical examination, ultrasound, CT exam and CA 125 dosage, every 6 month for two years.

In nine patients there was no evidence of tumour recurrence. In 33 patients tumour recurrence such as: pelvic tumour masses (5 cases), lymph nodes metastasis (15 cases), peritoneal carcinomatosis (10 cases), ascites (18 cases), liver metastasis (4 cases) were identified. The sensitivity and specificity for recurrences depicted by CT examination were 84.84 % and 88.88 % respectively, but for tumour markers values the sensitivity and specificity were 63.63 % and 77.77 % respectively. The results obtained for the association between CT exam and tumour markers was 90.90 % for sensitivity and 100 % for specificity. Conclusions: CT examination has a high sensitivity and specificity for the detection of post therapy recurrences in ovarian cancer and these values can be significantly increased in patients with high blood levels of tumour markers. In detail, the TRUS examination of the Peripheral, Transitional and Central Zones of the prostate is demonstrated step-by-step, in order to help the examiner avoid false-positive and false-negative results. The limitations of the TRUS technique are pointed out, so that the examiner can overcome the restraints of the method and reach a histologically proved diagnosis. Video cases of stage C PrCas are presented in order to indicate the optimal way for the correct staging. Last but not least, the suggested technique, in order to avoid complications arising from TRUSguided biopsies, is thoroughly presented.

Evaluation of localized prostate cancer with high resolution MRI using an integrated endorectal pelvic phased-array coil C. Duffaut-Andreux 1 , M.-F. Bellin 2 , A. Delcourt 1 , A. Haertig 1 , E. Chartier-Kastler 1 , F. Richard 1 , P.A. Grenier 1 ; 1 Paris/FR, 2 Villejuif/FR Purpose: To assess the efficacy of integrated endorectal pelvic phased-array MRI in staging clinically localized prostate cancer and to illustrate the spectrum of imaging findings, including pitfalls and limitations of MRI. Methods and materials: 24 patients were examined with an integrated phasedarray coil on a 1.5 T MR unit before radical prostatectomy. T1 and T2-weighted high resolution MR images were obtained. MR findings and pathological results were retrospectively compared. Results: Stage T2 disease was diagnosed by MRI in 20 patients and stage T3 in 4 patients. Pathologic staging demonstrated stage pT2 in 21 patients and stage pT3 in 3 patients. MRI staging accuracy was 83.3 % with a sensitivity of 66.7 % and a specificity of 85.7 %. Tumour extension into the periprostatic tissue and neurovascular bundle involvement, were the most indicative findings of extraprostatic disease. MRI accuracy was improved in the subgroup of patients with PSA level superior to 10 ng/ml (accuracy 100 %). Conclusion: Integrated endorectal pelvic phased-array MRI is accurate in the staging of prostate cancer, particularly in patients with PSA level greater than 10 ng/ml.

ProstaScint imaging in evaluation of patients with metastatic prostate cancer and assessment of post-prostatectomy recurrence I.V. Zaytsev, D.S. Bandari, R. Saul, N. Tebyani, H. Pham, J. Kaswick, C.A. Yee; Los Angeles, CA/US Purpose: The role of ProstaScint imaging has not been fully elucidated. We present our experience with this modality. Methods/materials: This is a retrospective study comprised of two groups of patients evaluated with ProstaScint at our institution. First group included metastatic disease in patients with intact prostate, second group post-prostatectomy patients evaluated for recurrent disease.

Results: 86 patients were studied. First group included 37 patients; second group 49. In Group I the scan was positive for prostate cancer localised within the prostate gland in 84 % of subjects, pelvic lymph nodes in 22 %, distant lymph nodes in 14 %. In Group II the scan was positive in prostatic bed in 41 % of the patients, pelvic lymph nodes in 18 %, distant lymph nodes in 16 %. Since all of Group I patients had proven cancer in prostate gland, all of those with negative scans were considered false negatives (16 %). Seven patients underwent radical prostatectomy after ProstaScint; pathology showed that 3 had positive pelvic nodes and 4 were node negative. Of the 3 positive, 1 had a positive scan in the pelvic node area and of the 4 negative, 3 had negative scans in the pelvic node area. 13 Group II patients had anastomotic biopsies, all were negative; out of them 4 had positive scans in the prostatic bed. Conclusions: The ProstaScint scan has relatively high false negative rate in intact prostate. In post-prostatectomy patients, the ProstaScint scan was positive in 31 % of patients with negative anastomotic biopsies. Further correlation with tissue diagnosis is necessary for better understanding the role of ProstaScint. Aim of the study was to evaluate the disease extent before treatment and the initial results after chemotherapy in patients with testicular carcinoma by PET with [ 18 F]-fluorodeoxyglucose ( 18 F-FDG). Methods: We have examined 10 patients (males, 19 -28 years of age) with histologically verified testicular carcinoma. All patients underwent surgical treatment and chemotherapy. PET with 18 F-FDG was carried out twice before and after 2 -3 courses of the chemotherapy. PET-scans (Ecat Exact 47) were performed 90 min after intra-venous injection of 370 MBq 18 F-FDG in "Whole body" mode. Ratio between level of tumours and normal testicular tissue uptake (T/NT ratio) was calculated. Results: All cases of testicular carcinoma were seen as "hot spots" and T/NT ratio was more than 1.5. In all patients an evidence of the tumour metastatic extension was observed: 10 patients had metastases in retroperitoneal lymph nodes, 5 patients in pelvic lymph nodes and 3 patients had the lung metastases. After 2 -3 courses of the chemotherapy a complete normalization of 18 F-FDG uptake was noticed in 9 out of 10 patients. Absence of 18 F-FDG uptake in tumour and metastases demonstrated chemotherapy efficiency. Residual metastases after treatment were observed only in one case and became a reason for treatment continuation. Conclusion: PET with 18 F-FDG allows assessing chemotherapy efficiency in patients with metastatic testicular carcinoma. Detection of viable residual metastases after treatment is an important key to individualized therapeutic strategy and therefore to reduction of therapy-related morbidity and toxicity.

The incidence, velocity, and duration of reflux in testicular veins of normal subjects evaluated with color duplex sonography E. Kocakoc, A. Kiris, I. Orhan, Z. Bozgeyik, M. Kanbay, E. Ogur; Elazig/TR Purpose: The reflux in the testicular veins has a crucial role in the diagnosis of varicocele. The aim of this study is to quantify duration and velocity of reflux in testicular veins of normal subjects evaluated with color duplex sonography (CDS). Methods and materials: 70 healthy volunteers, whose physical examination and semen analysis were normal, were recruited for scrotal CDS examination. The maximum venous diameters in testicular veins both during normal respiration and Valsalva manoeuvre were measured. Veins greater than 2 mm of diameter were considered as having varicocele and involved sides were not included in the analysis. Velocity and duration of reflux in testicular veins during Valsalva maneuver were measured with CDS. Results: Fourteen of one hundred and forty testicular units examined had varicocele and were excluded from the analysis. Of one hundred 26 testicular units, 57 had no reflux and 69 had reflux. In 30 cases the reflux was on the right side with a mean duration and velocity of 1.08 ± 0.50 s, 4.13 ± 2.02 cm/s, respectively. 39 of those who had reflux were on the left side with a mean duration and velocity of 1.05 ± 0.51 s, 4.87 ± 2.31 cm/s, respectively. The incidence of reflux was significantly high on the left side. Conclusion: Normal size testicular veins has remarkably high incidence of reflux that may be considered as a physiologic process. Presence of reflux in subfertile individuals with normal vein diameters is a diagnostic criterias, but it is necessary to quantify the reflux to prevent misdiagnosis and unnecessary surgery.

Usefulness of pelvic MRI in patients with hematospermia T. Yamamoto; Maizuru/JP Purpose: To evaluate the usefulness of pelvic MRI in patients with hematospermia. Materials and methods: 8 patients who complained hematospermia between April 1999 and March 2001, were examined by pelvic MRI. Morphological abnormalities and changes in the signal intensity of prostate and seminal vesicle as well as the presence of dilatation of deferent duct and paraprostatic venous plexus were analysed. If the signal of seminal vesicle content was higher than prostate in T1WI, it was diagnosed as a focus of bleeding. We compare MRI with transrectal ultrasonography examination. Results: 7 out of 8 patients showed abnormal findings in MRI analysis. 7 patients had seminal vesicle bleedings and 2 of them were associated with the Mullerian duct cysts. There were no abnormal signal in prostate. Transrectal ultrasonography examination was only effective in detecting Mullerian duct cyst in 2 patients. Conclusion: MRI was considered less invasive, superior in the qualitative diagnosis, and effective in detecting the bleeding sites. Further evaluation was considered difficult only with MRI even though the bleeding sites were detected with this method, however, it would be a beneficial analytical method to rule out other complicated diseases.

Usage of magnetic resonance (MRI) with dynamic contrast enhanced imaging in the diagnostic of prostatic cancer A.A. Mazaev, E.S. Belisheva, Y.G. Alyaev, E.A. Bezrukov; Moscow/RU Purpose: Of the study was to estimate the possibility of MRI with dynamic contrast enhanced imaging in the detection of prostatic cancer. Materials and methods: 23 patients from 45 to 70 years old were included in the study. First group consisted of 5 patients with previously detected prostate cancer, and the second group (18 patients) consisted of patients with suspected cancer (PSA 3.5 -20 ng/ml FPSA/TPSA 7.5 -40 %, inconclusive results of sonography). MRI was performed by Signa Horizont imager (GE) with field 1.5 T. Dynamic contrast enhancement was done with Gd-DTPA-BMA (0.2 ml/kg) in 7 time intervals using fast gradient pulse sequences and pelvic coil. Results: In all cases MRI detected low-intensity foci on T2-weighted images in the peripheral zone of the prostatic gland in patients with verified cancer (first group). In patients with suspected cancer in 4 cases MRI detected characteristic features of the cancer. Three more cases were found by dynamic contrast MRI. In all other cases MRI showed presence of prostatic hyperplasia. Results of MRI were confirmed by prostatic biopsy under US guidance. Conclusion: Dynamic MRI of the prostatic gland helps to visualize foci of prostatic cancer in cases of doubtful results of sonography.

Scrotal MRI with surface coil as a diagnostic alternative for problematic cases O. Akin, A.M. Agildere, H. Musapasaoglu, I. Tekin, A. Kurt, C. Tarhan; Ankara/TR Purpose: Although ultrasound is conclusive in most of the patients with scrotal pathology, magnetic resonance imaging with surface coil is helpful in complicated cases. We present different scrotal pathologies along with their MRI findings. Methods and materials: Ten patients between 2 to 68 years of age were studied. Multiplanar images with different sequences were obtained with surface coils. MRI findings were confirmed with surgery in four patients and with biopsy in one patient. Clinical correlation was performed for the remaining patients. Results: Three patients had intratesticular mass on MRI. Pathologic diagnoses of these lesions were mixed germ cell tumour in one patient, Leydig cell hyperplasia in the second and plasma cell granuloma in the remaining. Three patients complained of swollen and painful scrotum. MRI correctly established the diagnoses of epididymal abscess in one patient, scrotal wall abscess in the second and epididymo-orchitis in the third. In one patient with testicular microlithiasis, MRI showed structural changes due to chronic epididymitis and excluded any accompanying intratesticular tumour. One patient had an area of fibrosis in the testis due to old infarction. In two patients testicles were non-palpable. MRI revealed undescended testicle in one patient and atrophic testis in the other. Conclusion: Scrotal MRI with surface coils is an alternative imaging modality particularly in patients with inconclusive scrotal US findings.

Differential diagnosis of tuberculous (TB) and non-tuberculous epididymitis on ultrasonography S. Lee 1 , Y. Kim 1 , B.H. Koh 2 , Y.S. Kim 1 , C.K. Park 1 , D.W. Park 1 ; 1 Kuri/KR, 2 Seoul/KR Purpose: To evaluate reliable findings of ultrasonography to aid in diagnosing tuberculous (TB) epididymitis. Methods and materials: We retrospectively analysed sonographic findings of TB epididymitis (12 cases) confirmed by operation and microbiologic study and of non-TB epididymitis (18 cases) diagnosed clinically or pathologically. TB epididymitis patients were 22 -74 years old (mean, 44 years). Operations were performed in 6 cases of TB epididymitis. Positive urine AFB stain and effective anti-TB medication were seen in other 6 cases. Non-TB epididymitis patients were 1 -62 years old (mean, 31 years). Three cases were confirmed by surgery and 15 cases were proven to be non-TB epididymitis showing improvement by antibiotic therapy. We analysed sonographic findings such as distribution, echogenecity, abscess formation, calcification, scrotal wall thickening, reactive hydrocele, combined testicular involvement and evidence of TB in other organ. Results: In all cases, involved portions of the epididymis are enlarged with homogeneously or inhomogeneously decreased echogenecity. The TB epididymitis mainly involves epididymal tail (6 cases, 50 %) and may contain calcifications (2 cases). In addition, there is frequent involvement of other organs such as lung or genitourinary tracts (6: pulmonary, 3: renal, 1: prostate, 1: urinary bladder). In majority of the non-TB epididymitis, the thickness of the scrotal wall is usually more than 3 mm (mean 4.8 mm), and combined reactive hydrocele with septation is present. Conclusion: Involved portion of epididymis, presence of calcifications, thickness of scrotal wall, nature of the reactive hydrocele, and coexistent TB involvement of other organs are helpful findings to differentiate between TB and non-TB epididymitis.

Transrectal ultrasound (TRUS) and guided biopsy of the prostate -a practical pictorial guide R.R. Misra, C.V. House, C. Allen, M.J. Kellet; London/GB Introduction: Transrectal ultrasound (TRUS) is an imaging modality that offers the opportunity to perform guided needle biopsy of the prostate. An ageing population and increasing use of prostate specific antigen (PSA) as a screening tool, has led to an increase in the number of requests for TRUS and prostatic biopsies. This pictorial presentation aims to demystify this essentially straightforward procedure, using both photographic and ultrasonic illustrations. It provides an introduction for those new to the procedure and a focus of discussion for those experienced in its application. We prompt a discussion of the complimentary and contrasting techniques used at The Middlesex and Central Middlesex Hospitals. Materials and methods: A sound knowledge of prostate zonal anatomy is central to targeted biopsy. Normal prostate anatomy together with distribution of disease in the gland is summarised. Patient preparation is important for what many find a frightening prospect. Patient education and precautions taken to minimise complications, and the equipment used together with biopsy techniques employed are considered. Specific points examined include choice of antibiotics, methods of anaesthetising the gland and differing types of probes and biopsy needle guides. Results: Photographs and ultrasound images illustrate the description, enhance the understanding of the procedure and highlight differences between the procedures at our two hospitals. Conclusion: As with any ultrasound procedure there is a learning curve, and a sound understanding of zonal anatomy is fundamental if more radiologists are to acquire the skill of TRUS and biopsy. In turn this will minimise complications and maximise patient acceptability towards the procedure. 

We retrospectively reviewed the records of 18 patients who underwent colour-Doppler-US after a penile trauma. There were 2 iatrogenic traumas following intracavernous injection of vasoactive drugs, 11 blunt perineal traumas due to road traphic accidents, and 5 traumas during intercourse.

The 2 patients with iatrogenic trauma had a painful mass in the injection site. US demonstrated slightly hyperechogenic, inhomogeneous areas which became fibrotic after 1 -3 months. 8/11 patients with blunt perineal trauma developed high-flow priapism. Colour-Doppler-US identified the arterial-lacunar fistula in all patients. Repeated examination 6 -12 hours after angiography demonstrated successful embolization in 5/8 patients, while in the remaining 3/8 patients further embolisation was necessary. 3/11 patients with blunt perineal trauma had intracavernous hematoma which appeared at US as an hypoechoic area in the corpus cavernosum. These 3 patients had normal flow in both cavernosal arteries. After 1 -3 months 2/3 patients with intracavernous hematoma had a cavernous fibrotic scar; blood leakage was identified near the scar in one patient who developed venous-occlusive dysfunction. All 5 patients with intercourse traumas had painful penile swelling; 3/5 had extraalbugineal blood effusion. The albugineal tear was demonstrated by US in 2/5 patients with penile fracture. Conclusions: Colour-Doppler-US has a useful role of in the differential diagnosis of penile traumas. . Imaging protocol included: 5 mm collimation, pitch of 1.5, injection of iodinated contrast medium with high flow rates: 3 -4 ml/s. Arterial and venous phases were performed. All the lesions were pathologically proved. Results: Metastatic involvement was as follows: bone (52; osteolytic), lungs (65; lymphangitic involvement 3/65; 50 % of the lung metastases were hypervascular), pleura (10), heart (2), brain (9), salivary glands (4), orbits (1), liver (42), pancreas (9), spleen (1), adrenals (10), lymph nodes (12), muscles (4), peritoneum (5), subcutaneous tissues (3), small bowel (2), colon (1). Conclusions: CT proved useful in the identification and sometimes characterization of metastases from renal cell carcinoma. The evaluation of the arterial phase using high flow rates is of paramount importance.

Acute ureterolithiasis: Contrast-enhanced helical CT (CE-HCT) findings A. Nunziata, O. Catalano, M. Esposito, A. Siani; Naples/IT Purpose: Unenhanced HCT is used as the initial choice to investigate urinary colic. We illustrate the spectrum of findings recognisable when contrast medium is administered. Methods and materials: From January 1997 to December 2000, 211 patients were studied with nonenhanced HCT (110 with ureterolithiasis, 28 with alternative causes, and 73 with no evident cause). Seventeen of these underwent CE-HCT for different purpose: Differentiation from phleboliths (n = 2), assessment or exclusion of alternative/associated causes or of otherwise relevant conditions (n = 12), complication detection (n = 1), pre-treatment planning (n = 2, including 1 with a single kidney). Results: Ten out of 17 patients ultimately had an acute obstruction due to stone disease showing: delayed (n = 9), prolonged (n = 10), striated (n = 1) and/or dense renal enhancement (with loss of corticomedullary differentiation) (n = 9), delayed collecting system (n = 9) and/or ureteral opacification (n = 8), perirenal extravasation (n = 1). Conclusion: HCT is currently employed in the evaluation of ureteral colic. A minority of patients may require a CE-HCT study. Radiologists should be aware of the related findings. Learning objectives: This exhibit illustrates the spectrum of CE-HCT findings in patients in urinary colic due to ureteral stones. Although nonenhanced HCT is generally adequate to assess this occurrence, contrast medium administration may be necessary for various reasons and radiologist should be aware of the related features and pitfalls of the technique.

Ultrasonographic diagnostic criteria of minimal calyx dilatation S. Petcu, V. Popita, I.-R. Negrea, L. Florescu, I.-R. Ivan; Cluj-Napoca/RO Purpose: Assessment of the quantifiable ultrasonographic criteria for the appreciation of minimal calyx dilatation (MCD) allowing an early diagnosis of urinary obstruction and avoiding an excessive diagnosis of low degree hydronephrosis. Methods and materials: The authors have studied 200 patients with renal symptomatology who at standard ultrasonography, power Doppler color and Whittaker test showed MCD. The diagnosis was confirmed by urography and CT. In 40 cases dynamic renal scintigraphy with 99 Tc-DTPA was performed. Results: The ultrasonographic sign encountered in all the 200 cases with MCD was hyperechogenic papilla. Other signs were caliceal stems with diameters over 5 mm (70 %), dilated hyperechogenic fornix (30 %), well defined prominent pyramids (20 %). The cases with pelvic diameter over 3 cm were considered first degree hydronephrosis. Only the cases with calyx dilatation maintained both in inspiration and expiration were considered (after deep expiration the calyceal stems can be mistaken as dilated). Colour power Doppler technique confirmed the diag-nosis in the cases of vesicoureteral reflux. Scintigraphy revealed alterations of the renal function in 10 cases. MCD was the only sign in 37 patients with microlithiasis and 14 patients with incipient renal tuberculosis. Conclusions: MCD must be appreciated according to quantifiable criteria avoiding overdiagnosis in hyperhydratation, diuretic medication, apnea following forced expiration, insipid diabetes, etc or of interpretation of MCD as normal in patients with renal diseases.

Evaluation of urological complications after renal transplantation with contrast-enhanced MR-urography M. Cohnen, P. May, L.W. Poll, M. Brause, A. Saleh, A. Scherer, U. Mödder; Düsseldorf/DE Background: The diagnostic work-up of renal transplants with impaired function due to urological problems can be difficult. This study was performed to assess sensitivity and specificity of non-invasive contrast-enhanced MR-urography (MRU). Methods: 35 patients with renal transplants (25 -71 a.; mean: 53.4 a.) and sonographically diagnosed hydronephrosis or perirenal fluid collections were assessed by MR-urography. MR-examinations were carried out at a 1.5 T clinical scanner (Vision, Siemens) with a 512-matrix contrast enhanced fat suppressed T1-weighted FLASH-3D-sequence in breath-hold technique. MIP-reconstructions in nine different angles were used to produce MR-urography. MRU diagnoses were compared to operative results. Results: In all patients, images with sufficient contrast in the renal collecting system were obtained. Hydronephrosis was confirmed in 20 patients, eight patients showed a different pathology while 7 had normal findings. Compared to operative results, sensitivity of MRU was 100 % with a specificity of 78 %, respectively. One ureteral stone was misdiagnosed as a stricture, two suspected ureteral stenoses could not be found on operation. Conclusions: Contrast-enhanced MR-urography is a highly sensitive and specific non-invasive method to evaluate patients with a suspicion of typical post-transplant urological complications. It may replace invasive procedures such as antegrade pyelography in the pre-operative workup. Purpose: Traumatic thrombosis of the renal artery is a known but rare complication of abdominal trauma. Frequently is associated with injuries to other organs, with other abdominal injuries present in 67 % of them. Our purpose: to describe the findings in CT, in arteriography and to emphasize the important role of early diagnosis. Methods and materials: We reviewed patients with traumatic thrombosis of the renal artery who were treated in our Hospital during a 6 year period. We found three cases in which the only manifestation of the abdominal trauma was the occlusion of the renal artery. CT-scan was performed in all cases and the arteriography in two. Results: CT was diagnostic in all cases. Two patients had a total absence of nephrogram, one of them with a "rim sign", and the third had an unusual pattern of medullary-enhancement. The arteriography confirmed the CT findings, observing an abrupt termination of the proximal left main renal artery. In the other case the follow-up demonstrated a global renal atrophy. The recanalisation was not required because of the time elapsed between the accident and the diagnosis (more than 5 hours). Purpose: To describe the typical and atypical radiological findings of pyelocalyceal diverticula with or without complications and to emphasize the imaging findings that influence surgical decisions.

We reviewed the files of 50 patients with symptomatic or incidental calyceal diverticulum and compared the efficacy of excretory urography, ultrasonography, helical CT and retrograde pyelography for the diagnosis and pre-therapeutic assessment (location of the diverticulum, size, diameter of its neck, presence of stony, hemorrhagic or infectious complications). Results: Excretory urography and retrograde pyelography were the most accurate imaging modalities in determining the precise locations of the diverticula. Sonography misinterpreted diverticula as cysts in 75 % of patients and underestimated the occurrence and number of calculi within diverticulae. Helical CT with late films rarely identified the diverticular neck, but was helpful for detecting complications, including calculi (n = 10) and abscesses (n = 4). Hydrocalix, a complicated cystic mass, and renal papillary necrosis may simulate a pyelocalyceal diverticulum. Conclusion: Pyelocalyceal diverticula are best identified with excretory urography or retrograde pyelography. Helical CT is useful to detect complications.

The incidence of simple renal cysts depending on age and sex S. Petcu, V. Popita, I.-R. Negrea, I.-R. Ivan, L. Florescu; Cluj-Napoca/RO Purpose: We aimed at establishing the incidence, depending on age and sex of simple renal cysts (SRC) in patients examined by ultrasonography for extrarenal diseases.

The study included 1950 patients, 920 males and 1030 females aged between 16 and 84 years (mean age 50.5 years) examined by ultrasonography for various indications unrelated to kidney diseases. The complex cysts detected by ultrasonography and confirmed by CT and pathology were not included in this study.

Results: A number of 285 cases of SCR were detected (14.61 %) of which 26 % were bilateral, 38 % on the right side and 32 % on the left side. The incidence of the cysts was higher (p < 0.05) in males (63.15 %, n = 180) than in females (36.84 %, n = 105). The highest incidence was found in the age group 70 -80 years (21 %). The size of the cysts was from several millimetres to 7 cm, the most frequent ones being those below 2 cm. Solitary cysts were found in 212 cases, 2 -4 cysts in 44 cases and 4 -5 cysts in 29 cases. The patients with more than 5 cysts were considered as having a subclinical form of multicystic kidney disease.

Most SRC are asymptomatic and are diagnosed randomly by ultrasonography. SCR are more frequent in males and their incidence increases with age, suggesting a degenerative development mechanism.

Cystic We used his classification in our study. 14 complex cyst in 14 patients (size range 2.5 -10 cm) were evaluated by CDS before and after intravenous bolus injection of Levovist (10 ml -300 mg/ml). We evaluated the presence or absence of these CD and sonographic signs such as: (1) females) 24 to 85 years old (mean 57 years) who underwent a nephrectomy in our hospital, were diagnosed histologically as cases of diffuse XGP. 14 patients were examined with CT preoperatively, 9 of which after intravenous administration of contrast medium. The CT findings were analysed retrospectively. Results: In all 14 patients (100 %) the characteristic finding was an enlarged kidney, with multiple, low density, water filled areas arranged in a hydronephrotic pattern. In all patients there was extension of the inflammatory process in the perirenal space. In 8 patients (57 %) there was thickening of the Gerota fascia, in 6 (43 %) there was a large stone in the collecting system and in 3 (21 %) air within the renal parenchyma. Posterior pararenal space, psoas, diaphragm and spleen were involved in 6 (43 %), 5 (36 %), 2 (14 %), and 1 (7 %) of patients respectively. 4 of the 9 patients who received intravenous contrast medium showed no renal excretion and 5 had enhancement of the rims surrounding the cavities.

The diverse CT findings in patients with diffuse XGP may complicate preoperative diagnosis, but the characteristic features are an enlarged kidney with multiple low density water filled areas and the perarenal extension of the inflammatory process. In the absence of these, diffuse XGP is unlikely to be the correct diagnosis. Purpose: Survey the wide variety of neoplastic and non-neoplastic processes involving the kidney. Illustration of the radiological findings in conditions such as simple cyst, hyperdense cyst, multilocational cystic nephroma, renal cell carcinoma, urothelial carcinoma, renal sarcoma, metastasis, lymphoma, oncocytoma, angiomyolipoma, abscess and other entities. Illustration of most characteristic features of these masses on CT images. To emphasize differential diagnosis of these lesions based on CT findings.

There is a wide range of masses that affect the kidney, such as simple cyst, hyperdense cyst, multilocational cystic, nephroma, renal cell carcinoma, urothelial carcinoma, renal sarcoma, metastasis, lymphoma, oncocy-

Genitourinary toma, angiomyolipoma, abscess and other entities. Clinical onset is insidious and in some cases, renal masses may be incidental findings in ultrasonographic studies developed in asymptomatic patients. CT is performed to determine a diagnostic approach. Results: Frequently ultrasonograhy is performed for the initial study of masses involving the kidney. In some cases it is difficult to determine the benign or malignant nature of the lesion, the origin or the extent. This exhibit will illustrate most CT characteristic features of renal masses, which may be very helpful in differentiating them and making the diagnosis. Conclusion: CT studies may define the nature, anatomic origin and extent of renal masses, and help to differentiate benign from malignant lesions. Methods: Ten healthy volunteers (group 1) and 24 patients with duplex US findings indicative for renal artery stenosis (group 2) underwent Magnetic Resonance (MR; 1.5 T). MR protocol included a 3D PC sequence in the axial plane, followed by a 2D fast PC triggered sequence on a sagittal-oblique plan perpendicular to the studied renal artery. Maximum systolic velocity (MSV), mean velocity (MV), mean arterial flow (MF), time to systolic peak velocity (TSP) were calculated. Contrast enhanced MR angiography (CEMRA) and conventional angiography were also performed in group 2. Quantitative data were obtained on an independent workstation with a dedicated software. Results: In group 1 values of MSV (44.41 ± 9.2 cm/s), MV (27.27 ± 5.67 cm/s), MF (371.93 ± 98.7 ml/min) and TSP (194.5 ± 52 ms) were comparable with that reported in literature. In hemodinamically significant stenoses values were: MSV (21.91 ± 7.9 cm/s), MV (12.1 ± 4.6 cm/s) MF (130.41 ± 57.2 ml/min) and TSP (213.3 ± 86.7 ms). In patients with non-significant stenosis values were: MSV (47.9 ± 14.8 cm/s), MV (35.2 ± 8.4 cm/s) MF (373.9 ± 50.15 ml/min) and TSP (194.7 ± 37.8 ms). On CEMRA, degree of stenosis was overestimated in 2 cases in which normal flow data were observed on 2D fast PC and confirmed on conventional angiography. Conclusion: 2D fast PC could provide additional information in patients with renal artery stenosis. Quantitative analysis can be helpful particularly in patients with non conclusive findings on CEMRA.

CT angiography of the renal arteries in patients with potential renovascular hypertension I. Tsitouridis, D. Melidis, P. Papapostolou, A. Morichovitou, M. Emmanouilidou, S. Chondromatidou, S. Stratilati, E. Kakarinou; Thessaloniki/GR Purpose: To emphasize the role of CT Angiography of the renal arteries as a routine method in patients with potential renovascular hypertension. Materials and methods: We examined 67 patients with a history of hypertension to look for the configuration and flow of the renal arteries. All the examinations were performed using a spiral CT Picker PQ 5000, scanner. Scans were obtained with slice thickness 3 mm, pitch 1.5 and reconstruction every 1.5 mm. We also use several reconstruction algorithms including SSD, MIP and volume rendering techniques. Confirmation of the diagnosis was made with Color Doppler Ultrasonography and contrast enhanced MRA of the renal arteries in all cases and with additional intraarterial DSA in 24 cases. Results: The majority of the patients had normal renal arteries (62/67). We made the diagnosis of renal artery stenosis in only 5 patients. The incidence of renal artery stenosis in our group of 67 patients with potential renovascular hypertension was 7.4 %. Conclusion: We believe that CT angiographic study can be performed as an outpatient examination. It requires less time, is very accurate and can be used in routine basis for patients suspected to have renovascular hypertension.

Variation of stone visibility on KUB in different subgroups of patients with renal colic S. Yilmaz, M. Çubuk, O. Eray, C. Oktay, O. Bircan, T. Sindel; Antalya/TR Purpose: Although noncontrast spiral computed tomography (NCSCT) proved superior in demonstrating ureterolithiasis, plain film (KUB), ultrasonography (US) and intravenous urography (IVU) are still widely used because of concern on cost and radiation dose. In this study, we investigated the effect of different patient characteristics in determining the best radiological modality for ureterolithiasis. Methods and materials: In 106 patients (92 stone positive, 14 stone negative) whose SCT results were confirmed and KUB images were available, value of KUB in the demonstration and exclusion of ureterolithiasis were evaluated in different subgroups. KUB results were interpreted as in agreement or disagreement with those of SCT for the detection of ureteral stones. In both groups, differences in patient age, gender, and body status, as well as the stone location and size were studied using 2 and independent samples T test. Results: In demonstrating or excluding ureterolithiasis, KUB was in agreement in 83 and disagreement in 23 out of 106 patients. In the agreement group, patients were significantly younger, thinner and predominantly female. Their ureteral stones were proximally located and larger in size (p = 0.05). Conclusion: In young, thin and female subjects, KUB is more likely to correctly identify or exclude ureterolithiasis. Thus, in such patients, it can be used alone or in combination with US or IVU. Old, large and male subjects are less likely to benefit from KUB; such patients can directly undergo SCT imaging.

Quantification of renal cortical echogenicity (MPD) measurement in patients with anorexia nervosa (AN) G. Feuchtner, L. Pallwein, A.H. Schuster, F. Frauscher, D. zur Nedden, W. Biebl; Innsbruck/AT Purpose: Previous studies described an increase of renal cortical echogenicity in patients with AN due to chronic hypocalemic nephropathy and rhabdomyolysis. The goal of our study was to quantify these changes by means of quantitative ultrasound using MPD measurement. Material and methods: We examined the kidneys in 25 well hydrated females (mean age 22 ± 7) with clinically confirmed AN (mean BMI: 15.3) using high resolution US-transducers (7.5 MHz) and standardized B-mode settings. For quantification of renal cortical echogenicity we determined the MPD values within a region of interest (ROI) and standardized them in relation to a tissue equivalent phantom (MPD-Index). We compared the results with functional renal blood values and a control group (n = 20, BMI = 17 -20). Results: The mean MPD-Index was 0.96 ± 0.04 SD (AN group) and 0.99 ± 0.01 SD (control group). In patients with chronic hypocalemia (n = 5) we measured a MPD-index of 0.94 ± 0.03 SD and the difference to the control group was significant (p = 0.036; student t-test). In patients with increased Creatinkinase (CK)-values, which indicates rhabdomyolisis (n = 3), the MPD-Index was 0.88 ± 0.05 SD resulting also in a highly significant difference to control group (p < 0.001; student t-test). Conclusion: Using quantitative ultrasound, a significant increase of renal cortical echogenicity could be determined in patients with anorexia nervosa with chronic hypocalemia and increased CK-values. In addition to laboratory changes, the MPDindex could be an objective value in the diagnosis and follow up of acute and chronic nephropathic changes in patients with AN.

Percutaneous renal core biopsy in children -four years of study J.G. Glowacki 1 , K. Hyla-Klekot 2 , R. Kachel 1 ; 1 Zabrze/PL, 2 Chorzow/PL Purpose: In the last four years we performed 39 percutaneous renal core biopsies (PRCB) in children. The aim of the study was to show the technique we used and how our developing experience influenced the duration of examination, age of children and increased the number of glomeruli in specimen. Material and methods: 39 children with diagnosis of glomerulonephritis (21), chronic glomerulonephritis (12) and connective tissue diseases (6) were examined. The PRCB was performed under general anaesthesia with ultrasound guidance using 16 G needle with "gun" system. One specimen for optic and the second for electron microscope was taken. Results: The youngest patient in the first year of the study was 10, in the last 3 years old. The total time of the examination from the first skin cut to the end of the procedure changed from mean 7. 

eruli changed from 9 to 16 respectively. The complications were hematuria up to 2 days in 6 children, erytrocyturia in 17 and epirenal hematoma in 2. These haematomas did not require surgery. Conclusions: Today PRCB is used as a necessary diagnostic method in renal diseases in children. The skill and experience of a radiologist performing the examination has an influence on duration of examination (anaesthesia), lowering the age of patients and increases the number of glomeruli in the specimen. Junior interventional radiologist should be trained under the guidance of an experienced radiologist.

Cryoablation of renal lesions: MR imaging follow-up at medium field strength (0.5 T) G. Cardone, A. Cestari, G. Guazzoni, G. Balconi; Milan/IT Purpose: We evaluate the MR patterns in the follow-up of renal lesions treated with laparoscopic cryoablation, using a medium field strength system (0.5 T) Method and materials: 15 patients with 20 renal masses underwent laparoscopic renal cryoablation. All patients underwent follow-up MR imaging 24 h after surgery, and than at 1, 3, 6 and 12 months. An US/CT-guided needle biopsy was performed 6 months after cryoablation. All examinations were performed using T1w, T2w and ce-T1w sequences. Two radiologists retrospectively reviewed MR images for (a) signal intensity (SI); (b) size; (c) vascularization and (d) perinephric changes after treatment. Results: (a) T1w images showed 12 cryolesions isointense (60 %) and 8 heterogeneously isointense to renal parenchyma (40 %). On T2w images all cryolesions were hypointense with iso or hyperintense foci; (b) Lesion size: 24 hours after treatment all cryolesions were more than 1 cm larger than the original masses; cryolesions decreased in size an average of 38 % at 1 month, 46 % at 3 months, 64 % at 6 months and 80 % at 12 months after cryoablation; (c) ce-T1w images showed complete ischemia of all cryolesions; (d) After surgery we found retroperitoneal effusion in all cases; 4 cases (20 %) showed a little haematoma; 18 (90 %) cases showed low SI foci due to reabsorbed haemostatic material. Conclusion: After renal cryoablation, medium field strength MR imaging revealed similar characteristics and similar SI patterns when compared to high field strength MR imaging results previously reported. Cryolesions decreased in size less than shown in other studies, probably due to less magnetic susceptibility sensitivity. In the upper aerodigestive tract atypical carcinoids (AC) are rare tumors mainly localized to the supraglottis. Since microscopically AC may be misinterpreted as lymphoepithelial or undifferentiated SC-carcinomas, they often remain unrecognized. Their higher aggressiveness compared to SCC requires the search for metastases of the skin, liver, lung, and bone, extended operative resection margins of the primary, with neck dissection in all cases. Thus, the pretherapeutical immunohistochemical diagnosis of an AC is essential. By presenting two cases, we demonstrate how CT and MRI can be helpful during the diagnostic work-up. Methods: Two cases with immunohistochemically proven AC of the supraglottic larynx have been documented as entirely submucosal with CT and MRI and followed up during and after therapeutic measures. Results: In addition to laryngoscopy, cross-sectional imaging revealed entirely submucosal homogeneously enhancing tumors suggesting the rare diagnosis of a solid supraglottic tumor other than SCC. Thus, transmural biopsies and immunohistochemical analyses were performed diagnosing AC. In one case, however, at first a lymphoepithelial carcinoma was assumed and radiation therapy was performed only. After immunohistochemical analysis AC was diagnosed (T2N2cM0). In spite of surgery including bilateral neck dissection the latter patient died of metastatic disease. The other patient (T2N0M0) has been disease-free after vertical hemilaryngectomy and unilateral neck dissection followed by radiation therapy. Conclusion: The two cases demonstrate how cross-sectional imaging can improve the detection of entirely submucosal solid tumors, drawing the attention to a rare differential diagnosis (such as an atypical carcinoid), and guiding the ENTsurgeon to the most successful transmucosal biopsy site.

US findings in metastatic disease to the thyroid S. Chung 1 , E.-K. Kim 2 , K. Oh 2 ; 1 Sungnam/KR, 2 Seoul/KR Purpose: To evaluate the sonographic findings of thyroid metastasis from nonthyroid primaries. Materials and methods: The study included nine patients during a 5-year period who had histopathologically proven metastatic disease to the thyroid. Ultrasonography was available in all cases. Ultrasound-guided needle aspiration was performed on 10 suspected nodules on ultrasound. We analysed the ultrasonographic findings of the thyroid nodules irrespective of aspiration and also the ultrasonographic findings of all thyroid nodules proved by aspiration. Results: The primary neoplasms were breast carcinoma (n = 6), uterine leiomyosarcoma (n = 1), cervical carcinoma (n = 1), and nasopharyngeal carcinoma (n = 1). Excluding 2 nodules, 8 metastatic nodules showed an ill-defined hypoechoic character with heterogeneous texture. Two nodules showed relatively circumscribed iso-or hypoechoic character with a cystic portion. From the analysis of ultrasonographic finding including all thyroid nodules irrespective of the pathologic proof, 7 cases -excluding 2 from the 9 cases -showed unilateral or bilateral multiple nodules suspecious of metastases. There was no evidence of microcalcification in any thyroid nodules. Conclusion: The sonographic findings of thyroid metastatic nodules were not specific, but unilateral or bilateral multiple suspected thyroid nodules without microcalcification may be suggestive of metastatic nodules in patients with known primary non thyroid tumor. 

3.75 mm, interval 1.25 mm, pitch 3:1. 3D VR was performed on a workstation. Morphologic assessment of 3D CT laryngography and comparison between images from three different maneuvers was performed and assessed visually by consensus of three radiologists. Axial CT images and direct laryngoscopy were compared with 3D CT laryngography. Results: Among 25 patients, laryngeal cancer (n = 10), hypopharyngeal cancer (n = 9), papilloma (n = 2), vocal cord palsy (n = 2), hypopharyngeal obstruction (n = 1) and laryngocele (n = 1) were confirmed by operation or direct laryngoscopy. Morphologic assessment of the laryngeal and hypopharyngeal lesions was easier in CT laryngography than axial images. In laryngeal lesions, the image with neutral position was better than those of the other maneuvers. In hypopharyngeal lesions, the images with Valsalva and modified Valsalva maneuvers were better than that of neutral position. Tl scintigaphy is higher than that between 18 F FDG PET and 131 I scintigraphy or that between 201 Tl scintigraphy and 131 I scintigraphy. The combination of 18 F FDG PET, 201 Tl scintigraphy, and 131 I scintigraphy improved markedly the rate of detecting recurrent or metastatic thyroid cancer after total thyroidectomy.

Estimation of antithyroid drug dose in Graves' disease: The value of quantification of thyroid blood flow with color duplex sonography A. Saleh, J. Feldkamp, E. Godehardt, M. Cohnen, L.W. Poll, A. Scherer, U. Mödder; Düsseldorf/DE Purpose: To evaluate whether there is an association between the antithyroid drug dose that is needed to establish euthyroidism and thyroid blood flow measurements. Methods and materials: Graves' disease patients who had been euthyroid for at least 12 weeks under drug therapy were selected for the study. 23 patients (16 women, 7 men) were included in the study. The mean age (SD) was 41 (± 12) years. The sonographic protocol consisted of spectral duplex sonography of the thyroid arteries and color flow mapping of the thyroid gland. Results: There was a strong correlation between the color pixel density (CPD) and methimazole dose (r = 0.79, p < 0.0001). Simple linear regression was then performed in order to predict adequate methimazole maintenance dose from CPD values. The methimazole dose that is needed to reestablish euthyroidism could be calculated with a coefficient of determination of R2 = 0.622. No relationship between thyroid volume, peak systolic velocity, volume flow rate, degree of thyroid hypoechogenicity and duration of antithyroid drug therapy on the one hand and methimazole dose on the other hand could be found. We found weak to moderate correlations between PSV and CPD (rp = 0.52, p = 0.03) and VFR and CPD (rp = 0.57, p = 0.02), but no association between CPD and the duration of antithyroid drug therapy (rp = 0.15, p = 0.54). Conclusion: In clinical practice, CPD measurements could be a useful tool for the clinical endocrinologist to estimate the antithyroid drug dose that is needed to maintain euthyroidism. (4) To achieve a practical and didactic method of viewing the normal anatomy of the neck with US. Material and methods: Gray-scale and color-Doppler imaging is performed in different patients using a high frequency linear array transducer (ATL 5000 HDI, Washington). Serial sectional US images of the neck correlating with drawings of the normal anatomy of this area are shown. Axial, sagital, and coronal views are used to illustrate the complex anatomic relationships. The different spaces and its contents are color coded to facilitate the comprehension. Results: US is an accessible and non-invasive technique to initially evaluate the cervical region. Evaluation with gray-scale and Doppler ultrasound can often determine diagnosis without further imaging procedure. US is sometimes insufficient for evaluating deep structures and anatomical spaces. Conclusion: An adequate knowledge of the anatomy of the neck is needed to correctly limit the differential diagnostic possibilities of pathology on this region. US is an available method for an accurate diagnosis of neck abnormalities with CT and MRI being reserved for cases, which require surgical management, additional information about deep structures or those in which there is discrepancy between the sonographic and clinical diagnosis. Conclusions: Carotid body tumours present some characteristic sonographic features. These include: precise location in the carotid bifurcation, wide splaying of the carotid arteries, solitary lesion, solid and heterogenous character. Colour duplex scanning shows vascular nature of the lesion, with low-resistance blood flow and indicates a blood supply from the external carotid artery. Ultrasound examination allows early detection and differentiation of carotid body tumours from other, non-hypervascular lesions at a similar location.

A case of laryngeal neurofibroma associated with neurofibromatosis type 2 M. Cihangiroglu 1 , S. Yilmaz 2 , H. Yildirim 1 , H. Ozdemir 1 , B. Altnsoy 1 , E. Ogur 1 ; 1 Elaz/TR, 2 Antalya/TR Purpose: Laryngeal neurofibromas have been reported in 16 patients with NF1, and schwannomas, in two patient with NF1 and 2 patients with NF2. To the best our knowledge our case is the first to document a laryngeal neurofibroma in a patient with NF2. Another unique feature of our case is the coexistence of multiple intramedullary tumors, which has not previously been reported in a patient with a laryngeal neurofibroma. Material and methods: A 32-year-old woman presented with a history of cataract, hoarseness and dysphonia since childhood, which had recently become worse. The patient also had hearing disability for low frequencies.

Results: Laryngoscopy revealed a 2 × 2 × 3.5 cm smooth-surfaced submucosal supraglottic mass. On CT of the neck, the lesion was seen as a round and welldefined hypopharyngeal mass extended through and obliterating the left supraglottic space. It was hypodense on unenhanced CT images and slightly enhanced with IV contrast administration. On MR imaging, the mass was heterogeneously hypointense on T1-weighted images and hyperintense on T2-weighted images, with moderate homogenous enhancement after gadolinium administration. Bilateral vestibular schwannomas and multiple intramedullary masses (presumed to be ependymoma or astrocytoma) were delineated on these MR images The patient was diagnosed as having NF-2 and the laryngeal mass was totally resected. On histopathological examination, the mass were consistent with neurofibroma Conclusion: Dysphonia and hoarseness may be the only presenting symptoms suggesting the possibility of a laryngeal nerve sheath tumor, and neurofibroma should be included in differential diagnosis of laryngeal masses in patients with NF2.

The role of color Doppler sonography in diagnosis of thyroid diseases G. Svanidze; Tbilisi/GE Purpose: The role of Color Doppler Sonography in diagnosis of diffuse and focal thyroid diseases. Method and material: 159 patients with thyroid gland pathology were investigated. 54 patients were noted to have diffuse enlargement, 81 had nodes and Hashimoto disease was present in 24 cases. In 38 patients with diffuse enlargement presence of nodules and microcalcifications was noted. 67 patients with thyroid node and Hashimoto disease underwent US-guided biopsy. Results: In patients with thyroid node hypoechoic lesions were seen in 17 cases, hyperechoic lesions were seen in 25 cases and in 39 cases adenoma, which were associated with halo signs. Hypoechogenic nodes were avascular by Color Doppler Sonography, in hyperechogenic structures there was some high resistance arterial flow when the size of the node was more then 2 cm. In cases of adenoma there was high resistance arterial flow around it and in the node arterial flow with little orificed venous vessels. In case of Hashimoto disease the thyroid nodule was hypervascular. Among the biopsies performed, 19 cases were suggestive of malignancy. Conclusions: Color Doppler Sonography is an important and significant aid in the diagnosis of thyroid nodules, in assessment of the degree of vascular change and is predictive for malignancy. The use of biopsy in cases of calcified nodes gives chance for accurate diagnosis.

Comparison of sonography and dual-phase 99 Tc-Sestamibi scintigraphy in the detection of parathyroid lesions in patients with hyperparathyroidism M. Kebapci, E. Entok, N. Kebapci, B. Adapinar, T. Kaya; Eskisehir/TR Purpose: The aim of this study was to evaluate and compare prospectively highresolution sonography and double-phase 99 Tc-Sestamibi scintigraphy for preoperative diagnosis of parathyroid disease. Methods and materials: A total of 37 patients underwent preoperative sonography and 99 Tc-Sestamibi scintigraphy prior to surgery. There were 32 (86.5 %) women and 5 (13.5 %) men, with a median age of 51 years (range 15 -76 years). The results were correlated with size, weight, location, and histopathology of excised parathyroid glands, thyroid abnormalities. Results: Surgery demonstrated 31 solitary parathyroid lesions (30 adenomas, one hyperplasia), two adenomas in four patients, three hyperplastic glands in one patient. In the patient with two hyperplastic glands, it couldn't possible to visualise the abnormal glands after the medical therapy. Overall sensitivity of sonography, and Tc-MIBI scintigraphy was 89 % and 72 %, respectively. Conclusion: Sonography is a good and a reliable technique to identify parathyroid lesions before surgery in patients with hyperparathyroidism. Sonography alone should be used as the first step for localization of parathyroid lesions before surgery. When the parathyroid glands are ectopic in location or sonography is suspicious, Tc-MIBI scintigraphy should be used.

Virtual laryngoscopy with a Valsalva maneuver technique A. Saiz, A. Sonlleva, J. Arrazola, F. Matute; Madrid/ES Purpose: To asses a special CT examination procedure for assessing laryngeal abnormalities. Methods and materials: 25 patients suspected of having laryngeal pathology underwent conventional dynamic contrast-enhanced CT. All patients also underwent a second Helical-CT during a Valsalva maneuver. After 3D reconstruction in the workstation the findings of the Valsalva virtual laringoscopy (VVL) were compared with those obtained by conventional virtual laringoscopy (CVL). All patients were controlled using laryngoscopy. Results: Helical CT scanning and 3D reconstruction were used to assess all 25 patients. Satisfactory VVL was achieved in 22 patient. Three (12 %) of our patients could not carried out the Valsalva maneuver properly because of their clinical situation. The overall pathologic findings were significantly better demonstrated (p < 0.001) on the Valsalva exams. In these type of examinations were significantly better evaluated (p < 0.001) the following structures: pyriform sinuses, aryepiglottic and pharyngeoepyglottic folds, arytenoid area surface, posterior pharynx wall and the vocal cords and the anterior and posterior commissurees (p < 0.01). The remainder of the studied structures did not demonstrate significant differences between both types of exams. Conclusion: VVL provides additional information to conventional axial images and optimizes CVL. It was useful for investigating laryngeal pathology improving delineation of the laryngeal anatomy, especially for pyriform sinuses, aryepiglottic and pharyngeoepyglottic folds, postcricoid area and subglottic lesions. In our experience combining VVL and axial images results in a further increase in diagnostic accuracy for protuberant and fixing lesions in the larynx.

3D power Doppler vascularization of thyroid nodules: A long period experience C. Caiazzo 1 , S. Spiezia 1 , L. Assentato 1 , F. Girolami 1 , G. Calvino 1 , G. Pagano 1 , R. Vivenzio 1 , A. Salzano 2 , A. Nunziata 1 ; 1 Naples/IT, 2 Frattamaggiore/IT Objective: The aim of our study was to confirm our previous findings regarding comparative evaluation of thyroid nodules with CD, PD and 3DPD images.

In the last three years we have performed 3DPD on 110 consecutive patients affected by thyroid nodules previously observed with PD. Two operators performed B-mode US and CD and divided nodules on the Lagalla criteria: 22 type I patterns, 55 type II patterns, 22 type III patterns and 11 type IV pattern. The same operators performed 3D reconstruction recorded on VCR and printed hardcopies. Two other different expert operators read only hardcopies and the recorded 3D images. Results: The classification of the second operators was: 0 case of no vascularization, 66 cases of peri-nodular vascularization, 33 cases of peri-and intra-nodular vascularization and 11 case of "thyroid inferno". Conclusion: Our results over a long period of experience show better visualization of vascularization with 3DPD that can help in diagnosis and therapy, replicating the conclusion of our previous, smaller, study. . Results: 7 patients were examined, 6 patients with keratocystic lesions, and 1 patient with a eosinophilic granuloma. In all patients it was possible to detect the nerve through its whole course. In 4 patients with minor cystic processes, the nerve could be identified both in the sagittal and coronal orientations. In 3 patients with major cystic lesions, only parts of the nerve were detected in each sequence. If the coronal and the sagittal sequences were evaluated together, the whole course of the nerve was identified. Conclusion: It is possible to detect the whole course of the inferior alveolar nerve through pathologic lesions in the mandible. In cases of large cystic lesions parts of the nerve are identified in a coronal or a sagittal view only. Therefore it is useful to perform a multiplanar MRI, at least in a coronal and sagittal planes.

Sentinel node radiolocalisation in head and neck skin cancers G. Tartaglione pre-set time) was started immediately after injections, in order to visualize the lymph drainage pathways. Intraoperative detection of the sentinel node was performed by γ probe and always by perilesional injection of patent blau. Results: The sentinel nodes were found, with lymphoscintigraphy, in all patients. We identified 33 sentinel nodes: 1 occipital node, 3 basal nodes of the tongue, 10 lateral superficial nodes (external jugular), 5 submandibular nodes, 5 submental nodes, 3 mastoid nodes and 6 supraclavicular nodes. In 20/22 patients the first node is localized in proximal cranial regions at 5 minutes post injection. Sentinel node positive rate was 13.6 %.

The flow of 99 Tc-Nanocoll in lymph pathways of the head is rapid. In our experience immediate scintigraphic imaging is essential to visualize the lymphatic drainage pathways and the first sentinel node. Radioguided biopsy of sentinel node is recommended within 3 hours. The injection of patent blau is inadvisable due to its poor concordance with lymphoscintigraphy.

Dental materials in MR imaging A. Bryll, A. Urbanik, A. Jurczak, A. Plociennik, A. Swierczyna; Krakow/PL Purpose: The aim of the study is estimation of degree of image disturbances caused by dental materials in MR examination, and risk of dislocation of ferromagnetic materials in magnetic field. Material and method: 25 samples of dental materials containing metals were examined. Some of the materials were in the form of cubes (10 × 5 × 5 mm) and some were inserted inside extracted teeth. Samples were placed in a gel phantom whose signal is close to the signal of soft tissues. Signa Horizon 1.5 T (GEMS) unit was used with spin echo sequences in T1 time with parameters TE: 20 ms, TR: 300 ms, slice thickness 3 mm, gap −1.5 mm, imaging matrix 256 × 256, FOV 20 × 20 cm. 

Results: Dislocation of samples during examinations was not noticed. Most materials produced similar artefacts. Samples of the same material in a certain shape causes formation of different artefacts depending on their position in respect to magnetic field lines. Additional artefacts, apart from those surrounding the sample, were notified. Conclusions: Materials from precious alloys cause a small degree of image disturbances, but artefacts may occur some distance away from them. Other materials (ex. Cr-Co-Mb, Cr-Ni) produce image deformations that may alter head MR images.

Obstructive sleep apnea syndrome (OSAS) morphometry: MR findings G. Fusco 1 , L. Macarini 1 , F. Macina 1 , A. Garribba 1 , G.C. Ettorre 2 ; 1 Bari/IT, 2 Foggia/IT Purpose: To determine the usefulness of MR imaging in patients with obstructive sleep apnea syndrome (OSAS). Methods and materials: We studied 45 patients (35 with OSAS and 10 snoring without OSAS) using a 1.5 T MR unit and available neck coil. Polysomnography were performed in all cases. We evaluated: sagittal pharyngeal diameters; length and width of soft palate and the angle resulting between cervical rachis axis and epiglottis; slope axis of the tongue; distance between hyoid bone (craniometric H point) and line joing the lower point of mandibular symphysis (craniometric Menton point) to geometrical centre of intervertebral space C2C3 (Me-C2C3) measured on the perpendicular. Results: Only in OSAS did we observe: narrowing sites < 5 mm (11 in velum palatinum and 4 in high hypopharynx); considerable length and width increment of soft palate (PNS-UT) compared to normal craniometrical valuation (from 28 to 40 mm); increase in cervical rachis axis and epiglottis angle; reduction of sloping angle of the tongue; increase of distance between hyoid bone (craniometric H point) and line Me-C2C3 measured on perpendicular; 3 different type of narrowing (roundish, elliptical having the greater axis anterior-posterior, ribbon-like with greater axis in lateral direction). Conclusion: We believe that reduction of sloping angle of the tongue, increase in angle cervical rachis axis and epiglottis angle, increase of distance between hyoid bone (craniometric H point) and line Me-C2C3 (due to lowering of hyoid bone) are specific patterns in patients affected by OSAS. MR evaluation is very important for a correct surgical approach.

Our experiences with inversion recovery fast spin echo in the head and neck region M. Godeny, K. Bocs, K. Horvath, E. Lengyel, E. Remenar, I. Polony; Budapest/HU Purpose: To compare the efficacies of inversion recovery fast spin echo (IRFSE) and T1-/T2-weighted FSE with and without fat suppression in evaluating head and neck disorders. Material and method: 92 lesions in 71 consecutive patients were evaluated. 75 lesions were related to neoplasms 15 lesions resulted from infection-and radiation reduced inflammation. T1-weighted conventional or FSE and IRFSE were obtained in all patients. In 28 patients fat suppressed T2-weighted FSE were also used and in 44 patients T1-weighted sequence with Gadolinium with and without fat suppression were applied. Results: The images were qualitatively compared for conspicuity of lesion margins and extent. IRFSE imaging improved conspicuity of 54 (56 %) lesions and showed equal conspicuity of 24 (26 %) lesions. Conclusion: IRFSE imaging improved visibility of lesions with long T2 relaxation times and of small lymph nodes. Early infiltration across fascial plans were also well visualised with IRFSE. By improving conspicuity of small lesions adjacent to or surrounded by fat IRFSE is very useful imaging of the head and neck lesions.

Radiopaque lesions on dental-CT: Histopathological correlation of 17 cases including inflammatory, dysplastic and neoplastic changes P.L. Peloschek, A. Gahleitner, M. Püregger, D. Turhani, I. Sulzbacher, C. Czerny, H. Imhof; Vienna/AT Purpose: The differential diagnosis of radiopaque reactive, dysplastic and neoplastic conditions of the jaw is a challenge to every radiologist dealing with dentists or maxillo-facial surgeons. Therapy is planned with respect to the radiological diagnosis, localization and size of a lesion.

The findings of 17 solitary and diffuse radiopaque lesions on computed tomography (CT) were correlated with histopathological diagnosis. After reviewing the literature, findings on axial CT-scans and Dental-CT-reconstructions were reviewed. CT was performed pre-operatively on a single-slice scanner (Philips CT Secura; 120 kV, 70 mA, scan time 2 seconds, slice thickness 1 mm, table index 1 mm, high resolution filter) and Dental-CT-reconstructions were made with a commercially available graphic workstation (Philips EasyVision, Dental Reformatting Package). The histological specimens obtained at open surgery were sent to the pathologist for detailed classification according to the criteria published by the World Health Organisation. Results: The radiological findings of complex composite and compound composite odontoma, benign cementoblastoma, cemento-ossifiying fibroma, osteoma, florid osseous dysplasia, periapical cemental dysplasia, fibrous dysplasia, sclerotic osteomyelitis and carcinoma-induced sclerosis could be correlated with the pathohistological diagnosis. Almost all lesions showed typical radiological signs. Discussion: Specific diagnosis is possible if the anatomical and pathological features of the jaw are known. Nearly all radiopaque lesions of the jaws are of benign nature. Some of these lesions become locally expansive and destructive or tend to recur after resection. In rare cases a carcinoma of the oral cavity can imitate osteosclerotic osteomyelitis.

Bilateral brachial plexus plexiform neurofibromas in Neurofibromatosis type 1: MR findings in one case G. Zuccoli 1 , F. Nicoli 1 , F. Ferrozzi 2 , A. Troiso 1 , M. Rossi 2 ; 1 Reggio Emilia/IT, 2 Parma/IT Neurofibromatosis type 1 (NF1) is a neurocutaneous syndrome inherited in an autosomal dominant trait with variable penetrance. Affected patients are at increased risk of developing both benign and malignant tumors. Neurofibromas are a typical finding of the disease. In fact, the presence of two or more neurofibromas of any type or one or more plexiform neurofibroma is one of the diagnostic criteria for NF1. Neurofibromas usually occur in the skin, head and neck, pelvis and extremities. Neurofibromas are benign tumours infiltrating and enlarging peripheral nerves characterised by typical MR patterns. Neurofibromas rarely involve the brachial plexus. To our knowledge, a bilateral simultaneous brachial plexus involvement by neurofibromas in NF1 patients has not been reported in scientific literature. We show Magnetic Resonance (MR) findings of a NF1 disease patient presenting with bilateral, histologically proven, brachial plexus neurofibromas.

Fused CT and MRI imaging of zygomatico-maxillo-orbital fractures using the DentalStudio software M. Kozakiewicz, P. Arkuszewski, M. Olszycki, A. Przygonski, B. Goraj; Lodz/PL Aim: of this study was to present the advantages of combined imaging of zygomatico-maxillo-orbital fractures using DentalStudio, a computer software application devoted to digital fusion of CT and MRI data. Materials and methods: The sCT and MRI images were obtained in 10 patients with zygomatico-maxillo-orbital fracture of the orbit. Volumetric acquisition of spiral CT (Picker PQ 5000) scans and MRI images (Siemens 1.5 T) were obtained in the frontal plane. Using a computer workstation equiped with DentalStudio, CT and MRI fusion was produced. These combined images were evaluated for the the quality of visualisation the injured structures, especially the intraorbital soft tissues. All patients also underwent postsurgery sCT and MRI examinations and post-processing utilizing image fusion to assess the reposition of the injured structures. Results: Fracture fissure morphology and the surrounding soft tissues were visualised accurately especially in the orbit floor. Fused images also helped evaluate the bone fragment reposition and location of muscles and nerves after surgery. Conclusion: Zygomatico-maxillo-orbital fractures have very variable morphology and because of this, the novel visualisation techniques presented here are highly recommended. The objective of this study was to measure the dynamics of contrast enhancement in the nerve and to examine whether these measurements provide additional prognostic information. Material and methods: In a prospective study, MRI images using a dynamic T1 gradient echo sequence were obtained from 13 patients with idiopathic facial paralysis on the first day of inpatient treatment, one measurement before and three successive measurements after the administration of Gd-DTPA 0.1 mmol/kg. Regions of interest in the five intratemporal segments of the facial nerve were defined for the quantitative evaluation of the results. Results: Contrast-agent dynamics in the IAC suggested that patients with poor outcomes showed maximum values in the second contrast-agent sequence and a signal intensity decline in the third sequence. Values measured in patients who progressed to full recovery reached plateau results in the last two sequences. In the first contrast-agent sequence in the IAC, all patients with favorable outcomes showed signal intensity increases of less than 60 % whereas the two patients with unfavorable outcomes were found to have values exceeding 100 %.

The results confirm the prognostic value of the evaluation of pathological changes in the IAC; it was possible to observe specific differences between patients with poor outcomes and patients with favorable outcomes in the contrastagent dynamics. The fact that these results were in agreement with the clinical course of the disease shows that measurements in the IAC may suffice to provide valuable prognostic information.

Embryological, clinical, and radiological correlation in malformations of the facial massif K. Bouzaidi, W. Douira, E. Menif, K. Arnouni, A. Baccar, K. Chelaifa, N. Ben Neji, R. Slim, S. Hachicha; Tunis/TN Purpose: Malformations of the facial massif are rare congenital lesions which demonstrate a large clinical polymorphism. The purpose of this work is to review cranio-facial morphogenesis while clarifying the embryological and clinico-radiologic correlations. Materials and methods: We retrospectively studied 4 cases of facial malformation in patients aged from 15 months to 3 years. All the patients were investigated with high resolution CT in axial and coronal planes, with 3D reconstructions. In 3 cases a cerebral MRI was performed. Results: Imaging revealed bilateral maxillary and labio-palatine fissures in 2 cases; one case of an associated mesencephalic atropy, an agenesis of the corpus callusum and a case of lissencephaly. In the 2 other cases, there was a dermoid cyst of the back of the nose associated in one case with agenesis of the corpus callusum and an interhemispherical lipoma. Results: After multiplanar reconstruction it was possible to obtain images of the greater petrosal nerves of all 18 patients. The average diameter of the nerve was found to be 0.68 mm (0.5 to 0.9 mm). Signal intensities increased by an average of 50.3 % (-10 to 146 %) after contrast agent administration. Whereas two patients showed slight signal intensity decreases, 16 patients exhibited signal intensity increases. No correlation could be established between signal intensity increases and past medical history, clinical condition, laboratory findings or electrophysiological data. Conclusions: In contrast to quantitative measurements in the facial nerve, ROI measurements in the greater petrosal nerve do not produce results that can be correlated with past medical history, clinical condition or laboratory findings. For this reason, MRI images of this nerve do not enable us to draw conclusions on the etiology of idiopathic peripheral facial paralysis.

Etiological diagnosis of facial palsy: contribution of MR imaging E. Menif, E. Hemaied, H. Ben Romdhane, K. Arnouni, I. Turki, G. Besbes, R. Slim, S. Hachicha; Tunis/TN Purpose: To estimate the possibility of using MRI in cases of isolated peripheral facial palsy (FP), not improving with medical treatment. Materials and methods: A prospective study, conducted over 30 months, including 23 isolated peripheral FP in 22 patients (12 males), average age 42 years. Two patients had presented one zona in the weeks preceding the appearance of the FP. In 2 patients, there was a history of trauma. An audio-vestibular exam was performed systematically. CT (n = 5) and MR (n = 22) scans were conducted. The MRI study included the brain with a CISS 3D sequence focused on the acousticofacial region, a SE T1 study of the facial nerve pre and post contrast was also performed. Results: Five patients had a perception deafness. A CT showed a fracture of the temporal bone, not involving the VII at one patient. MRI found 7 neurinomas of the VIII nerve associated in one case with an adenoid cystic carcinoma of parotid and in a 2 nd case with a facial nerve schwannoma. In the 2 cases of trauma, a hematoma of the geniculate ganglion and a contusion of the VII nerve were shown. In 5 cases, enhancement was noted, in 2 cases, the enhancement was in relation to a zoster virus infection. Finally in a case, a multiple sclerosis was discovered. Conclusion: It seems useful to suggest MRI in cases of non-regressive peripheral PF, allowing therapeutic changes to be made.

Normal radioanatomy and malformations of the ear K. Nouira, H. Ben Romdhane, E. Menif, S. Dhaouadi, M. Ben Messaoud, R. Slim; Tunis/TN Purpose: The diagnosis of malformations of the ear has widely benefited over recent years from the use of high resolution CT (HR CT). It requires, however, a good knowledge of normal radioanatomy. The purpose of this work is to establish the criteria of normality of the ear and to illustrate malformations encountered in congenital deafness. Materials and methods: A prospective analysis of 300 normal temporal bones was performed over a 6 month period. In addition, 34 cases of malformations of the ear, encountered over the preceding 10 years, were reviewed retrospectively. These patients presented with transmission deafness in 25 cases; with perception deafness in 5 cases and with a mixed deafness picture in 4 cases. Meningitis was noted in 3 patients and in 4 cases there was an otomandibular syndrome. All our patients had a HR CT with multiplanar and 3D reconstructions. Systematic measurements were performed on the temporal bone structures. Results: External ear malformations were isolated in 7 cases (25 %) and associated with middle ear malformations in 21 cases (75 %). An abnormality of the internal ear was noted at 6 patients, 4 cases of which were of Geyser's ear. It was bilateral in 50 % of cases and in one case joined associated with stenosis of the internal auditory meatus.

The authors suggest precise scanographic criteria for normality of the temporal bone, detecting the most subtle abnormalities. Various types of malformations are illustrated.

Purpose: The purpose of this study was to determine the accuracy of high resolution CT (HRCT) and MRI in both detection and staging of labyrinthine fistula secondary to extensive cholesteatoma. Material and methods: Forty seven patients (28 M, 19 F) presenting with a secondary middle ear cholesteatoma were examined preoperatively by HRCT. Eight were evaluated by MRI using a 3D-CISS acquisition in order to improve the detection of invasion of the membranous labyrinth using a 3 level grading scale: (1) normal fluid, (2) focal, and (3) diffuse obliteration of labyrinthine fluid. Results: In 46 patients (97 %), the HRCT image-based assessment of osseous labyrinthine fistula coincided with the surgical findings (14 cases of labyrinthine fistula suspected by CT were surgically confirmed). The image-based assessment in the remaining patient, who had massive cholesteatoma, was false-positive. The 3D-CISS sequence depicted either a normal membranous labyrinth (4 cases), a focal obliteration of the semi-circular canal (1 case) or a diffuse obliteration of the labyrinthine fluid (3 cases). Labyrinthine enhancement on post-Gadolinium SE T1 was noticed in one case of extensive fistula with labyrinthitis. None of the normal labyrinths were associated with labyrinthine fistula at surgery. Conclusion: HRCT is useful in the diagnosis of labyrinthine fistula. The 3D-CISS sequence allows a comprehensive preoperative evaluation of the membranous labyrinth.

Soft tissue masses of the tympanic cavity: Differential diagnosis P. Lozano, E. Delgado, R. Abelló, J. Aldoma, M. Baquero, M. Blanch, J. Dolz, M. Huguet; Barcelona/ES Purpose: Our purpose was to provide a comprehensive review of the current contribution of CT and MR to the diagnosis of soft tissue masses of the tympanic cavity Methods and materials: CT image acquisition was performed using a series of contiguous 1 mm thickness axial sections of the temporal bone in all the patients followed by reformated views in coronal and sagital planes. At MR, T1W, T2W and T1W post gadolinium axial and coronal contiguous 3 mm sections were obtained in selected patients. Results: Intratympanic soft tissue masses observed included: exposed jugular bulb, aberrant carotid artery, laterally placed carotid, carotid artery aneurysm, persistent stapedial artery, temporal bone herniation, facial and corda tympani schwannoma, acquired cholesteatoma, chronic and acute otitis media, fibrous tissue fixation, tympanosclerosis, postoperative middle ear: recurrent debris, recurrent cholesteatoma, granulation tissue, cholesterol granuloma and malignant neoplasms.

The evaluation and diagnosis of soft tissue masses of the tympanic cavity using spiral CT and magnetic resonance imaging is assuming an increasing role in clinical practice. High-resolution CT bone detail is the most helpful aspect of imaging for relating lesion extent to surgical ladmarks and for the determination of the surgical approach. MR can be valuable in the differential diagnosis when the identity of soft tissue masses is not obvious at CT and it allowed identification of tegmen defects and involvement of sigmoid sinus and brain.

Intracranial meningiomas with secondary extension to the infratemporal fossa D. Haba 1 , F. Veillon 2 , S. Riehm 2 , C. Aldescu 1 , J. Tongio 2 ; 1 Iasi/RO, 2 Strasbourg/FR Purpose: The aim of this paper is to present a study carried out in order to analyze the CT and MRI characteristics of intracranial meningioma involving the infratemporal fossa. Material and methods: We present seven cases (5 women and 2 men) with meningiomas of the cranial fossa studied with CT (n = 5) and MRI (n = 4). The different pathways for meningioma development in the infratemporal fossa were analyzed: the foramen ovale and the foramen rotundum. Results: In all cases, the meningioma originated in the middle cranial fossa and extended into the infratemporal fossa through the foramen ovale. In two cases the extension was both through foramen ovale and foramen rotundum. An extension to the middle ear was noticed in five cases through the eustachian tube and tegmen tympani. In four cases an important reduction in the diameter of the internal carotid artery was found. The invasion of the parapharingeal space and mucosa of the nasopharynx was observed in three cases. Conclusion: Understanding the different pathways of extension of intracranial meningiomas involving of the infratemporal fossa, middle ear and the parpharingeal space is essential for medical and surgical treatment. MRI was better than CT in delineating perineural and mucosal invasion.

Methods and materials: The study involved 32 patients with recognized inflammatory changes of maxillary sinuses on standard axial or coronary sections. The digital dataset of axial sections pictures was secondarily reconstructed in a highresolution algorithm and spatial reconstruction 3D CT was performed with the threshold from -150 to -300 HU, obtaining pictures of internal surfaces of maxillary sinuses assessed in real time and determined with virtual sinusoscopy (VS). Results: In 24 cases CT examinations revealed inflammatory changes within both maxillary sinuses and in 8 cases in one sinus. In 14 patients parietal, irregular thickening of the mucosa was recognized with accompanying fluid in 5 cases. Polypous changes were seen in 18 patients. The morphology of polyp surfaces was revealed by VS. In 4 cases of polyps whose diameter was smaller than 5 mm, the diagnosis was made at VS. In 5 cases the openings of the maxillary sinuses were of reduced size and in 3 other cases they were occluded. In 16 cases, highresolution sections showed various anomalies of the osteo-meatal complex. In 6 cases these were accompanied by periapical changes of the dental roots within the alveolar process of the jaw. Conclusion: Combining modern CT imaging techniques in the diagnostic evaluation of chronic maxillary sinusitis enables accurate diagnosis and determination of the probable etiology of disease, which may be useful in planning optimal therapeutic procedures.

Benign tumors of the ear: CT imaging V. Ryzhyk, V. Kmetyuk, D. Kravets, I. Reznik; Ivano-Frankivsk/UA Purpose: The diagnosis of benign tumors of the ear can be difficult. The aim of the study was to estimate tumor invasion of the middle and inner ear, as well to into brain tissues. Material and methods: We have examined 84 patients within a period of 2 to 10 years from disease onset. In addition to routine multiplanar radiography, all patients underwent high resolution CT (HRCT) of the temporal bones in the frontal plane (slice 2 mm, step 1 -2 mm; Somatom CR, SIEMENS). Results: Routine radiographs in several planes showed limited diagnostic information. CT revealed the following lesions: osteoma 21 (25 %), exostosis 9 (10.7 %), polyp 14 (16.7 %), meningioma 9 (10.7 %), auditory nerve neurinoma 14 (16.7 %), glomus tumor 7 (8.3 %), seruminoma 10 (11.9 %) cases. The most frequent are osteomas and the less frequent glomus tumors. The distribution among the parts of the ear was the following: the external ear: osteoma 12, exostosis 9, seruminoma 10, polyp 10 cases; the middle ear: glomus tumor 4, facial neuroma 4, meningioma 5, osteoma 4 cases; the inner ear: glomus jugulare tumor 3, facial neurinoma 10, meningioma 4, osteoma 5 cases. Conclusion: HRCT is the method of choice for assessment of benign tumors of the ear. We had 61 histologically confirmed cases. One can readily state the level of tumor expansion that plays an important role in the treatment and functional prognosis.

Computed tomography of the ear in Pendred syndrome M. Goldfeld 1 , E. Nassir 1 , N. Loberant 1 , E. Hazani 1 , B. Glaser 2 , M. Gomori 2 , N. Bishara 1 ; 1 Nahariya/IL, 2 Jerusalem/IL Purpose: To summarize our findings of high-resolution CT of the ears in patients with Pendred Syndrome. Methods and materials: We performed CT of both ears in 12 patients, 3 females and 8 males aged 7 to 47 years (mean 21.9, median 20.5). All 12 patients had proven Pendred syndrome based on clinical evidence (goiter and deafness), and 11/12 had also undergone genetic mapping. CT examination of the ears were performed using a spiral technique (Twin Flash, Marconi, USA) with a pitch of 0.5, SW of 1 mm, IR of 0.5 mm, and reconstructed using a bone algorithm. The CT examinations were reviewed for anatomic derangements of the inner ear, including: vestibular aqueduct enlargement (normal up to 1.4 mm); absence of the modiolus and absence of the interscalar septum between the middle and apical turns of the cochlea. Results: CT was abnormal in all 12 patients. The modiolus was absent in all 12 patients. The interscalar septum was absent in 18 (75 %) of 24 ears. The aqueduct was enlarged in 20 (83 %) of 24 ears. No ear presented both normal vestibular aqueduct and normal interscalar septum-one or the other or both was abnormal in every ear examined. Conclusion: Patients with Pendred Sydrome show a very high prevalence of anatomic inner ear abnormality. The most consistent abnormality in our study was absence of the modiolus, noted in every ear examined. In addition, vestibular aqueduct enlargement and absence of the interscalar septum of the cochlea are very frequent findings.

Comperative analysis of ultrasound sinusoscopy with standard radiology investigations D. Nikolic, B. Josifovski; Skopje/MK Aim: Comparison of ultrasound sinososcopy of paranasal (PNS) and frontal sinuses (FS) with standard radiologic methods. Material and methods: Sinusoscopy investigations were made of the PNS and FS. Graphics were obtained from scan A. Based on the amplitudes a conclusion is drawn for paranasal sinuses status. Results are compared with standard radiographic according to Hurtc and CT findings. Results: From 35 cases with pathologic findings on A-scan, the majority are inflammatory changes of PNS (27/35), cystic formations (7/35) and solid tumor (1/35). We confirmed with radiologic tests: 24/27 inflammatory changes, 5/7 cyst changes and 1/1 solid tumor. Three results were appraised as missed diagnoses, while three were with imprecise differential diagnosis (between cystic and inflammatory diagnosis). Conclusion: (1) Ultrasound sinoscopy is a useful examination because it is safe an non-invasive and as a screening method minimizes the negative radiologic findings which is of particular importance in children.

(2) Tests can be repeated more times and therefore it is of great use in control check-ups.

Conventional sinus radiography compared with low dose CT and standard dose CT in the diagnosis of acute sinusitis T. Hagtvedt, T.M. Aalokken, J. Notthellen, A. Kolbenstvedt; Oslo/NO Purpose: To compare diagnostic information and dose of plain film radiography and low dose CT with standard dose CT in patients with acute sinusitis. Methods and materials: 47 consecutive patients with clinical suspicion of acute sinusitis were examined with plain film, low dose CT and standard dose CT on the same day. Conventional radiography was performed with three projections at 65 -70 kV. Standard CT was performed with 23 coronal scans at 200 mAs and 3 mm collimation. Low dose CT was obtained with 10 scans at 40 mAs and 1 mm collimation. Results: The sensitivity of plain film radiography was low (< 50 %) except for the maxillary sinus (80 %). The specificity was high for all sinuses. The sensitivity of low dose CT was 95 % and the specificity 97 %. The low mAs settings rarely induced errors of interpretation compared to standard CT. The average time spent in the conventional room was 15 minutes as compared with 6.5 minutes in the CT room. Effective dose of low dose CT was 3 % (0.02 mSv) compared to standard CT. Lens dose was 2 % (0.4 mGy). Effective dose and lens dose of conventional views compared to standard CT was 13 % (0.07 mSv) and 2 % (0.5 mGy) respectively. Conclusion: Low dose CT was faster and more accurate than plain film radiography, and with accuracy comparable to standard dose CT. The effective dose was lower and the lens dose comparable to that of plain film examination. Low dose CT could be the method of choice in acute sinusitis.

Malignant external otitis: CT and MR imaging in diagnosis and follow-up V.G. Katsiva 1 , E. Kailidou 2 , K. Proikas 2 , G. Karantzas 1 , V. Sandris 1 , M. Tibishrani 2 , A.H. Karantanas 1 ; 1 Larissa/GR, 2 Athens/GR Purpose: Malignant external otitis (MEO) is a severe infection of the external auditory canal that may progress into an osteomyelitis of the skull base. Our aim is to assess the role of CT and MRI in the diagnosis and management of the disease. Material and methods: Between 1998 and 2001, four patients with MEO were treated with long-term antibiotic therapy. The patients underwent CT and/or MRI examinations at the time of diagnosis (n = 4 pts), at the end of the treatment (n = 3 pts), in the asymptomatic period (n = 2 pts) and during recurrence-progression (n = 2 pts). We retrospectively evaluated the imaging findings and correlated them with the clinical course and outcome of the disease. Results: Cortical bone erosion of the external auditory canal was apparent on CT but not on MRI. Regarding the more central skull base, bone marrow changes and/or dural enhancement were demonstrated on MRI in all patients with osteomyelitis, whereas osteolysis was less evident on CT. After treatment, the affected bone failed to remineralize and showed adjacent sclerotic changes that persisted throughout the follow-up. Dural enhancement resolved 6 months after the end of successful treatment. Both modalities were effective in detecting soft tissue abnormalities beneath skull base but MRI was better in defining the anatomic extent of the disease. Soft tissue changes, although improved, did not disappear long after disease resolution Purpose: To present 3D volume rendering (VR) images using a 3DFT-CISS sequence in congenital anomalies of the inner ear structures. Materials and methods: Eight patients with congenital inner ear anomalies underwent a 1.5 T MRI (Vision, Simens, Germany) of the temporal bone. A 3DFT-CISS sequence (TR/TE/FA/slice thickness 12.25/5.9/70/0.6) was used. 3D VR was performed on an Advanced Workstation (GE, Milwakee, WI, USA). Results: Morphologic diagnosis was possible in all cases. One of eight patients had a unilateral anomaly, and the other seven cases showed bilaterality. Among sixteen ears of eight patients, many congenital anomalies were detected. These included: Cochlear Anomalies: hypoplasia (small bud; n = 2, under 2/3 turns; n = 4), incomplete partition (1 1/2 -1 2/3 turns; n = 7), Semicircular canal (SCC) Anomalies: agenesis of the superior (S) SCC (n = 3), agenesis of the common crus of S and the posterior (P) SCC (n = 4), small and bullous change of SSCC (n = 2), separation of SSCC (n = 1), agenesis of PSCC (n = 1), bullous change of PSCC (n = 3), hypoplasia of PSCC (n = 2), focal narrowing of PSCC (n = 1), bullous change of the lateral (L) SCC (n = 7), agenesis of LSCC (n = 2), small size of LSCC (n = 1), focal enlargement of the crura of LSCC (n = 1) and duplication of LSCC (n = 1). Conclusion: It is easier to evaluate congenital anomalies of the inner ear structures with the aid of 3D VR images.

The imaging of pulsatile tinnitus C.C. Basekim, F.A. Karsli, E. Silit, P. Zekai, H. Mutlu, A. Gungor, E. Kizilkaya; Istanbul/TR Purpose: To radiologically assess the underlying pathology of patients with pulsatile tinnitus. Method and materials: 74 patients with pulsatile tinnitus were evaluated radiologically. In 11 cases with objective tinnitus and in 63 cases with subjective tinnitus was described. Initial imaging methods for the patients with objective tinnitus are MRI, MRA, and/or DSA, and the patients with subjective tinnitus are HRCT with bone algorithm. Findings: Two arteriovenous fistulas, one aberrant ICA, one aneurysmal dilatation of ICA and seven atherosclerotic changes of ICA were depicted in patients with objective tinnitus. 21 high jugular bulbi, nine atherosclerotic changes, three dehiscence of jugular bulbi, one jugular diverticulum, two aneurysmal dilatations of ICA, two glomus tumor and one intracranial tumor were depicted in patients with subjective tinnitus, but in 24 patients the underlying pathology was not detected. Results: In the most of the patients with pulsatile tinnitus, prudent radiological examination can detect underlying pathology. The nasal cavity and paranasal sinuses are located adjacent to important structures such as brain and orbit. Various pathologic conditions can occur in these cavities. Some benign diseases of nasal cavity and paranasal sinuses such as papillomas (inverted papilloma, cylindric cell papilloma), aspergillosis, chronic expanding hematoma, and granulomata may extend into the surrounding structures, and therefore resemble malignant neoplasms on imaging. The knowledge of the characteristic imaging findings of these diseases and any differential features from malignant neoplasms is important. We reviewed cases with benign nasal/paranasal sinus diseases from radiologic and pathologic databases in our institutions from 1994 to 2001. CT and MR imaging findings and pathologic findings were retrospectively evaluated by three radiologists and two pathologists. Imaging findings of these lesions well represented their pathologic features and some of them were useful for differential diagnosis. This exhibit will demonstrate characteristic CT and MR imaging findings of benign lesions mimicking malignant neoplasms arising from nasal cavity and paranasal sinus in correlation with pathologic findings.

Unusual radiological patterns of fibrovascular ingrowth in hydroxyapatite orbital implants M. Sabatini, M.A. Blasi, F. Iannessi, C. Masciocchi, M. Gallucci; L'Aquila/IT Purpose: Isolated reports in the literature describe the radiological appearances of tumor-free orbital prostheses. We report the CT and MRI features of fibrovascular ingrowth in a hydroxyapatite implant mimicking a recurrence of retinoblastoma. Materials and method: A 2 years old girl affected with unilateral retinoblastoma had enucleation of the left eye and placement of an hydroxyapatite orbital implant. The patient was radiologically followed-up by plain and enhanced MRI after 4 and 6 months. A plain CT examination was performed after 6 months. The patient was lost to follow-up and received an enhanced MRI 1 year later. Surgery was planned to remove the implant and the specimen was histologically evaluated. Results: The short-term follow-up MRI revealed a mild contrast enhancement surrounding the implant. One year later MRI could revealed the presence of a 7 mm enhancing nodule markedly hypointense on both plain T1 and T2-weighted sequences within the implant. Due to the diffuse hyperdense appearance of the prosthesis, CT was unable to offer better characterization. The lesion was very suspicious for a recurrence of tumor. Surgical removal of the implant was then performed. Histopathology did not reveal the presence of any neoplasm, while inflammatory foreign-body reaction become evident. Discussion and conclusion: The unusual fibrovascular reaction resembled a recurrent retinoblastoma due to its low T1 and T2 intensity signal and contrast enhancement. This pattern, never described in literature, can be a cause of false positives, thus being an important limit to MRI specificity in investigating orbital recurrences.

Vascular malformations of the tongue studied with MRI: A report of three cases A. Barberi, M. Sensale, A. Del Vecchio, C. Corvino, S. Cappabianca; Naples/IT Purpose: Three consecutive cases of anomalous development of arterial vessels in the tongue diagnosed with Magnetic Resonance Imaging (MRI) are presented. MR exams were performed using superconducting scanner and Spin-Echo (SE) T1 weighted images in all orthogonal planes and SE-T2w images in the coronal and axial planes. Subjects: VP, male aged 35, with episodes of bleeding from the mouth. MRI showed multiple snake-like structures, with signal void in all sequences, originating from right lingual artery. DGL male aged 28, with a non-specific abnormal feeling at level of the tongue and episodes of bleeding from the mouth. MR exam demonstrated linear areas characterised by signal void both in T1 and T2w images, in the half left tongue, extending in the parotido-masseter region diagnosed as vascular malformation. MV male aged 29 with sub-continuous bleeding from the mouth. MRI demonstrated linear areas of signal void in T1w images, with highly increasing signal in T2w sequences in the tongue suggesting diagnosis of tongue teleangiectasia. Discussion and conclusion: On the basis of histological and embryological aspects, vascular abnormalities may be divided into haemangiomas and vascular malformations (either with high and low flow). Although angiography constitutes the better diagnostic imaging technique, providing direct identification of origin and extent of vascular abnormalities and also permitting the therapeutic management of some lesions, it is an invasive technique. MRI may be used as prior technique in diagnosis of vascular malformations providing a good depiction of the lesions and permitting differentiation of high and low flow abnormalities.

Jugular fossa lesions manifesting as low cranial nerve palsies A. Jeong; Seoul/KR Purpose: A variety of lesions may occur in the jugular fossa, arising from the structures normally found within the jugular fossa or from adjacent structures. Patients with lesions of the jugular fossa present with combinations of cranial nerve palsies (cranial nerves VII, IX -XII). The purpose of this exhibit is to review the radiologic anatomy of the jugular fossa and demonstrate a variety of diseases involving the jugular fossa together with histopathologic correlation. Materials and methods: We illustrate the radiologic (CT or MRI) findings and histopathologic correlation of 18 lesions involving the jugular fossa. Results: There were schwannomas (n = 3), metastases (n = 3), meningiomas (n = 3), paraganglioma (n = 1), rhabdomyosarcoma (n = 1), malignant granular cell tumor (n = 1), fibrous dysplasia (n = 1), apical petrositis (n = 1) and others (n = 4).

Conclusion: An understanding of the radiologic anatomy of the jugular fossa and reviewing the radiologic findings of a variety of jugular fossa lesions makes accurate diagnosis easier.

CT and MRI images in the evaluation of blow out type fractures of the orbit M. Olszycki, P. Arkuszewski, M. Kozakiewicz, A. Przygonski, B. Goraj; Lodz/PL Aim of the study was to compare the reliability of spiral CT (sCT) and magnetic resonance (MR) imaging in cases of blow out type fracture of the orbit and its postsurgery evaluation. Materials and methods: The sCT and MRI images were obtained in the coronal plane in 12 patients affected with blow out type fractures of the orbit. Using a computer workstation, CT postprocessing 2D and 3D reconstructions were produced. Images from both modalities were evaluated to assess the quality of visualization of injured structures, especially intraorbital soft tissues. All patients also underwent postsurgery sCT and MRI examinations to assess the reposition of injured structures. Results: The MRI images, in all the patients, allowed depiction of soft tissues in the region of injury, especially the position of muscles, more clearly then sCT. This helped to evaluate pathological lesions and to plan treatment more precisely. The bone structures of the orbit were visualised satisfactory only in the CT images and post-processing reconstructions. Conclusion: The MRI examination proved its superiority over the spiral CT in visualisation the intraorbital soft tissues in patients suffered from blow out type fracture. Spiral CT remains the more useful modality in depicting bone structures.

A. Kalai, I. Khettab, N. Belly, P. Halimi; Paris/FR Purpose: We have tried to define the MRI characters of Warthin's tumors in order to improve their diagnosis and management. Methods and materials: A retrospective study was performed on a series of 30 cases of Warthin's tumors, all being examined by MRI using T1-weighted, T2weighted and fat sat Gadolinium enhanced sequences. The comparison is made between this series with an another series of 30 parotid mass lesions. The cases of this control series have been chosen randomly from a population group of 100 parotid masses being explored by MRI before surgical excision. Results: We have showed sensitivity and specificity of the following elements permitting a better evaluation of parotid mass nature defined as Warthin's tumor before operation:

• Increased signal intensity in T1WI: sensitivity 20 %, specificity 90 % • Hyperintense fluid signal in T2WI without remarkable contrast enhancement: sensitivity 13 %, specificity 85 % • Punctiform hypersignal in T1WI: sensitivity 40 %, specificity 80 % • Increased homogenous signal intensity in T2WI without contrast enhancement: sensitivity 60 %, specificity 70 % Also the global shape of the lesions, their location in parotid gland and their border shape have been analyzed in the term of sensitivity and specificity. Conclusion: The MRI is able to make the diagnosis of Warthin's tumors with a great sensitivity and a reliable specificity by considering their whole semiologic characters.

Orbital wall reconstruction with alloplastic material. Evaluation with spiral CT and MRI fusion P. Arkuszewski, M. Kozakiewicz, M. Olszycki, A. Przygonski, B. Goraj; Lodz/PL Aim of this study was to evaluate the possibility of orbital reconstruction with polypropylene texture and its visualization by digital fusion of spiral CT (sCT) and MRI images. Materials and methods: The sCT and MRI images were obtained in the coronal plane in 20 patients with orbital fractures. Images of both modalities were fused using DentalStudio software. During surgery, muscles and other soft tissues were repositioned. The globe was supported with polypropylene texture. The same diagnostic procedures were applied after surgery. Results: In all the patients the fused images allowed depiction of the soft tissues in the region of injury, especially the position of the muscles. This was helpful in evaluating the extent of orbital involvement in the injury and in planning surgery employing the alloplastic material. In all patients diplopia was observed before treatment and in all cases normal vision was found after surgery. The maxillary sinus was separated from the orbit. Image fusion makes it easy to evaluate the soft and hard tissues of the orbit.

The polypropylene texture supports the globe as well as the barrier between maxillary sinus and orbit and can be satisfactory visualized using digital fusion of sCT and MRI images. Once TACE with Lipiodol-Epirubicin infusion and superselective gel-foam embolization of tumor-feeding vessels had been performed, patients underwent RFTA with an expandible hooked needle. All lesions were evaluated for change in size and vascularization by dynamic MRI. Α-fetoprotein levels, recurrence rates and survival rates were calculated. Results: One major complication occurred: portal vein thrombosis in a Child-B patient, who died one month after the treatment with liver failure. Dynamic MRI showed complete necrosis in 23/27 tumors (85.1 %). All patients were followed-up for 6 -30 months (mean 16.4 months). The local recurrence rate was 18.2 %. During follow-up over 6 months, 1 year and 2 years the cumulative survival rates were 91 %, 86 % and 73 % respectively. Conclusion: Combined treatment with TACE and RFTA is an effective therapy in medium-large HCC.

Percutaneous CT and ultrasound-guided treatment of liver cysts A.I. Ikramov; Tashkent/UZ Purpose: To evaluate the efficacy of percutaneous, image-guided treatment of liver cysts. Materials and methods: 66 patients with liver cysts (25 hydatid cysts and 62 celomic cysts) were treated with percutaneous procedures between V.1998 and V.2001. 29 cases were performed under CT control and 58 cases under ultrasound guidance. The ages varied between 8 and 76 years (mean 37.6). 76.5 % of cysts were located in the right lobe of the liver. In 23 patients multiple cysts occurred. 12 hydatid cysts were type I, 6 type II, and 4 type IV from the Gharbi classification. Mean cyst size was 6.8 cm (range 4.5 to 12.4 cm). CT and WE obtained follow up (up to 2 years) at regular intervals. Results: Image-guided aspiration was performed in 48 patients with celomic cysts and PAIR in 14 patients with hydatid cysts. In other cases we used percutaneous drainage. 71 cysts disappeared completely. 31 cysts in 25 patients showed a volume reduction greater than 50 %. In 11 patients (6 with hydatid disease and 5 with celomic cysts) the procedure was unsuccessful and needed surgical conversion. No deaths were seen during and after intervention. In 2 cases, with ultrasoundguided drainage, diaphragmatic damage occurred. Conclusion: Percutaneous, radiological-guided treatment of liver cysts is a relatively safe and effective method. CT control should be used for cysts in an atypical location. In other cases US control is recommended.

CT-guided aspiration and drainage of suppurated residual cavities after hydatidectomy A.I. Ikramov, N.M. Djouraeva; Tashkent/UZ Purpose: To evaluate the efficacy of CT controlled interventional procedures in suppurated residual cavities after hydatidectomy. Material and methods: CT-guided aspiration (FNA) and drainage were conducted on 62 patients with suppurated residual cavities after hydatidectomy. Age varied between 14 and 76 years (mean 39.6 years). The size of the cavities ranged from 4 -5 cm up to 12 cm. 76.3 % of cavities were located in the right lobe. In homogeneously low density containing cavities (+10 ± 18 HU) and thin walled cavities FNA procedures were performed. In other cases (37), with high density up to +25 ± 30 HU, we performed drainage with 9 -18 F pigtail catheters. In 12 cases, when the cavity size was greater than 10 cm, we placed two catheters.

Results: In 93.5 % patients, CT-guided intervention allowed the patient to achieve a full recovery. Repeated aspirations (from 2 up to 5) were conducted in 12 cases. One patient had a complication (partial lung collapse). In 4 cases, with ineffective drainage, surgical conversion was needed. Conclusion: CT-guided FNA and drainage procedures can be an effective method of treating suppurated residual cavities after hydatidectomy and may be alternative to surgical treatment.

Endovascular-surgical synchronous treatment in lower limb atherosclerotic disease G. Guzzardi, L. Monfardini, A. Calcaterra, G. Mastroeni, M. Natrella, A.R. Cotroneo; Novara/IT Purpose: We evaluated endovascular-surgical synchronous treatment in multilevel arterial occlusive disease to determine its effectiveness and benefit. Methods and materials: In the period between January 1999 and August 2001, 32 patients (29 M and 3 F: average age 68 a) underwent combined procedures for elective lower limb revascularization. All vascular reconstructive procedures were performed in a specially equipped operating room with digital subtraction angiography. Clinical indications for intervention included severe claudication (IIa and II b Leriche-Fontaine classification) in 68 % of cases, rest pain (III LF) in 15 % and gangrene (IV LF) in 17 % of patients. The procedures performed were both endovascular (PTA and stenting) and surgical (profundoplasty, femoral by-pass, cross over femoral by-pass, femoral TEA, femoro-popliteal by-pass and femorodistal by-pass). Results: An immediate technical success was registered in all patients, both for endovascular procedures and surgical treatment. No immediate complications were found. There was procedural morbidity in 4/32 (12.5 %) patients (two haematomas and two surgical wounds dehiscences). After a mean follow-up of seven months the patency rate was 96 % (one by-pass thrombosis). Conclusion: Synchronous procedures allow for more therapeutic options than performing a single approach (surgical or endovascular). It is a good option in cases of multilevel arterial occlusive disease and we have demonstrated encouraging midterm patency with a low complication rate in high risk patients.

Ultrasound imaging characteristics of non vascular complications in the post liver transplant patient P.S. Sidhu, S.M. Ryan, A. Shaw, R.C. Beese; London/GB Orthoptic liver transplant (OLT) patients are susceptible to a wide variety of complications. Vascular complications such as hepatic artery thrombosis and stenosis have well defined sequelae and are readily detected on colour Doppler US. Non-vascular complications are amenable to ultrasound examination; biliary complications, abdominal abscesses, fluid collections and haematomas. Less commonly pancreatitis and adrenal infarction are seen. With split liver and segmental liver transplants becoming more commonplace, patterns of complications, particularly fluid collections, have altered. Right sided pleural effusions may be associated with subdiaphragmatic collections. Recurrent malignancy and post transplantation lymphoproliferative disease occurs as a late complication of transplantation and US is often the initial imaging modality of diagnosis. This poster will illustrate the ultrasound findings of non-vascular post OLT complications, both commonly encountered abnormalities to rarer manifestations.

Interventional Radiology days (SD 7.9). No important complications were reported (one case of a small pneumothorax which resolved with conservative measures). Only 4 patients (17 %) required surgery. Radiological evolution revealed complete resolution in 74 % and persistent pleural effusion in 26 %. Conclusion: Fibrinolytic therapy with urokinase is a safe method that can help to resolve complicated pleural effusions. It can obviate the need for surgery in most cases with complete clinical and radiological resolution. It does not prevent subsequent surgery when necessary.

Improvement in palliative therapy of large, non-resectable hepatocellular carcinoma using a combination of transarterial chemoembolization and percutaneous ethanol instillation M. Kimpel, A. Lubienski, G.M. Richter, R. Bitsch, K. Aretz, L. Grenacher, M. Duex, G.W. Kauffmann; Heidelberg/DE Introduction: Percutaneous ablation procedures for HCCs are usually limited to max. 5 lesions with diameters not larger than 5 cm. Patients with non-resectable HCC often exceed these threshold values. We tried to establish a therapeutic alternative for large and multilocular HCCs combining transar terial chemoembolization (TACE) with percutaneous ethanol instillation (PEI). Methods and materials: Since 1998 we have treated 15 patients with large nonresectable HCC (min. 1 lesion larger than 5 cm in diameter) using a combination of TACE and PEI. At PEI up to 50 ml of concentrated ethanol was injected. The needles (1 -max. 5) were placed under fluoroscopy guidance and the position was guided by CT. TACE was performed by injecting Lipiodol and 200 mg Carboplatin in a "sandwich"-technique. Follow-up was obtained with contrast-enhanced dynamic MRI of the liver to direct further procedures according to depiction of active tumor nodules. Results: All patients had a histologically proven HCC on a background of liver cirrhosis (6 × CHILD A, 9 × CHILD B). The mean diameter of the lesions was 5.9 (2.5 -16) cm. Until now 4 patients have died giving survival times of 9 -36 months (Mean: 20). The mean survival of the remaining 11 patients is 10.4 months (Range: 6 -24). No major complications were observed, only post-embolization syndrome (transient fever, nausea and an increase in liver enzymes) with no therapeutical consequences. Conclusion: The combination of TACE and PEI is an efficient palliative therapy for patients with large non-resectable hepatocellular carcinoma. Survival rates seem to be improved compared to other treatment options.

Virtual CT intravascular endoscopy after stent placement for iliac arteriosclerosis obliterans: Phantom studies and clinical results T. Ihaya 1 , J. Nakanishi 1 , T. Ogawa 2 ; 1 Tottori/JP, 2 Yonago/JP Purpose: The aim of this study was to decide the optimal scan parameters in virtual CT intravascular endoscopy (VIE) in a phantom study and to evaluate the usefulness of VIE in clinical assessment. Materials and methods: In vitro stenosis was created inside a Palmaz stent in a vessel phantom and the optimal helical scan parameters for VIE were assessed. The vessel phantom was scanned with various beam collimations, scan pitchs and reconstruction algorithms. The quality of VIE was also evaluated in the variance of the angulation of a vessel phantom to the z-axis. Clinical investigation was performed in ten patients who had undergone previous stent placement for iliac arterial stenosis and/or occlusion. They consisted of ten men and the mean follow-up period after stenting was eighteen months. VIE images were compared with follow-up angiogram and intravascular ultrasonography. Results: The in vitro study showed that image quality of the stenotic lesion inside the stent depended on both scan parameters and the angulation of the vessel phantom to the z-axis. In vitro stenosis was poorly detected with an angulation over 75 degree to the z-axis. In the clinical assessment, VIE revealed one occluded lesion and two stenoses that were recognized in the follow-up angiogram. VIE did not show all of the stenoses that were shown by intravascular ultrasound. Conclusions: VIE is a minimally invasive imaging technique for the evaluation of restenosis inside a stent. It could be a useful 3D-imaging after stent placement in the iliac lesion.

Ultrasound guided percutaneous ethanol injection therapy (PEIT) for secondary or tertiary hyperparathyroidism S. Schamp, E. Dünser, H. Schuster, U. Lang, F.T. Meisl, H. Umek; Vienna/AT Purpose: Selective percutaneous ethanol injection therapy (PEIT) of the parathyroid gland has been shown to be effective in sufficiently ablating hyperplastic tissue. In the present study we report on our 3 year experience. Materials and methods: 17 uremic patients (mean age 52 ± 14 years) with hypercalcemia and severely elevated serum levels of parathyroid hormone were assessed for PEIT. Ultrasound examinations were performed using a GE-Logic700 ultrasound system, with a 7.5 MHz transducer. Tissue samples were obtained prior to intervention. After the enlarged gland had been located by echography, injection of 96 % ethanol was performed in a single session, using a 20 gauge modified chiba needle. Colour Doppler blood flow mapping was undertaken to confirm tissue destruction. Results: 10 patients were considered unsuitable for PEIT and underwent surgical parathyroidectomy (multinodular goitre, n = 4; deep localisation of the gland/anatomical difficulties, n = 2; too small to be viewed by ultrasound, n = 4). 7 patients were treated using PEIT. All patients tolerated the procedure well without major complications. Reversible recurrent nerve palsy was observed in one patient. 4 patients had to be retreated due to recurrent, symptomatic hyperparathyroidism, indicating incomplete necrosis of the parathyroid hyperplasic tissue. Following PEIT, serum values of total calcium and intact parathyroid hormone stayed within the target range for all patients. Conclusion: PEIT is a minimally invasive and safe adjunct to medical therapy in the treatment of hyperparathyroidism complicating chronic renal failure and can be used as a cost effective alternative to conventional parathyroidectomy in selected patients.

Radiation protection system for interventional therapy of hemodialytic access T. Haku 1 , T. Hosoya 2 , H. Ito 2 , M. Nishina 1 ; 1 Yonezawa/JP, 2 Yamagata/JP Purpose: To design a radiation protection system for hemodialysis access interventional therapy and to evaluate the usefulness of the system. Materials and methods: The radiation protection system consisted of an X-ray tube cover and image intensifier (I.I.) hood. The X-ray tube cover was made of a 0.35 mm Pb equivalent lead curtain to protect against backward scattering from the catheter table. The I.I. hood was attached around the I.I. to protect against scattering from the patient's upper extremity and the table. The I.I. hood was made from three parts; a device for hanging hoods, an acrylate hood with 0.50 mm Pb equivalent and a lead curtain hood. Scattering dose rates were measured with a ionization dosimeter in conditions with/without the radiation protection system. Results: The dose rate was most reduced with the I.I. hood + the X-ray tube cover. The maximum % decrease of dose rate was 100 % at a height of 150 cm (operator's head/neck region), 97 % at a height of 50 cm (operator's lower limbs) and 34 % at a height of 100 cm (operator's abdomen). The dose rate at a height of 150 cm was reduced by 81 % with the I.I. hood alone. The dose rate at a height of 50 cm was reduced by 97 % with the X-ray tube cover alone. At a height of 150 cm and 50 cm, a high dose rate area around the angiographic system disappeared with the use of the radiation protection system. Conclusion: The radiation protection system for hemodialysis access interventional therapy was useful in reducing scattered dose around the angiographic system.

Liver transplant in children: Interventional radiology in the management of biliary complications R. Nani, R. Agazzi, G. Perugini, M. Torda, C. Valentino; Bergamo/IT Purpose: Biliary complications are a major problem in liver transplantation. The incidence is 13 -25 %. We report our experience in the treatment of biliary complications following orthotopic liver transplantation in children. Materials and methods: In our hospital, from October 1997 to October 1999, 70 liver transplants were performed in 63 children (22 whole livers, 8 reduced livers and 40 split livers). The age of the patients was between 2 months and 19 years. The incidence of biliary complications was 23 %: 8 strictures at biliary-enteric anastomoses (47 %), 5 cut-edge leak bilomas (29 %) and 4 anastomotic leaks. We treated the biliary-enteric stenoses with PTC and bilioplasty. Bilomas were drained employing US-guidance, while anastomotic leaks underwent surgical intervention. 

Results: The strictures were resolved in 7 cases after 1 -3 bilioplasty sessions (87 %). One recurrence occurred in a successfully treated patient during a 18 -39 months follow up period. Cut-edge leak bilomas were successfully treated in 80 %. Conclusions: Interventional radiology plays a major role in the correct treatment of biliary complications after orthotopic liver transplantation in children, even in split livers or reduced livers. Surgery may be proposed only in few unsolved cases and in anastomotic leak.

Experience of transradial abdominal angiography and intervention T. Sato; Hiroshima/JP Purpose: In coronary angiography and angioplasty, the transradial approach has currently been accepted as an alternative catheterization method to the transfemoral or transbrachial approach due to the recent miniaturization of angiographic equipment. The purpose of this study was to assess the practical and clinical applicability of this method in abdominal angiography and intervention. Methods and materials: Between February 1999 and August 2001, 147 abdominal examinations were performed in 102 cases transradially. 71 cases were liver or gall bladder tumor, 15 cases were gastrointestinal tumor or bleeding, 10 cases were pancreatic tumor, 4 cases were renal tumor and 2 cases were renal or SMA thrombosis. 105 interventional procedures were performed. 12 cases were examined twice, 7 cases were done 3 times, 2 cases were done 4 times, 2 cases were done 5 times and 1 case was done 6 times during this period transradially. Results: Selective catheterization was successful in all patients. In HCC patients, supraselective catheterization was also possible and transar terial chemoembolization was performed. In patients with abdominal branch aneurysms, successful coil embolization was also performed. No puncture site hematoma was seen. No radial arterial stenosis or obstruction or thrombosis was noted. No cerebrovascular complications were noted. Conclusion: A transradial approach is an alternative entry method even in abdominal angiography and intervention. Purpose: 188 Re may be a valuable radionuclide to inhibit restenosis after arterial angioplasty. We wanted to evaluate dose-dependent growth modulating effects of the /γ emitter 188 Re on cultured human aortic smooth muscle cells (haSMC) and endothelial cells (EC). We searched for a dose that inhibits the growth of haSMC, which are mainly responsible for neointimal formation, but does not inhibit the growth of EC which are a natural inhibitor of neointimal formation. Method/materials: Two days after plating, the cells were incubated with 188 Re ( Emax 2.12 MeV, tissue rangemax < 10 mm, T1/2 17 h) for five days. The doses administered were 4 Gy, 6 Gy, 8 Gy, and 16 Gy. After five days, the radionuclide containing culture medium was replaced by non-radioactive medium. For the following 20 days the overall cell growth and clonogenic activity were analyzed. Results: The 4 Gy to 16 Gy groups presented dose dependent effects in both cell lines. HaSMC showed a complete growth arrest at 8 Gy lasting at least 20 days after radionuclide exposure and the clonogenic activity was strongly inhibited. EC showed a slight recovery in cell growth even in the 16 Gy group. Limited clonogenic activity was still observed. Conclusions: HaSMC and EC show a different sensitivity to the /γ emitter 188 Re. In HaSMC, growth can be controlled effectively with 188 Re (8 Gy) for at least 20 days after radionuclide exposure in vitro from doses of 8 Gy upwards, while EC still show a good potential for recovery even at 16 Gy. The purpose of this exhibit is to present a new technique using a vascular sheath for RF needle placement under US guidance in RF thermal ablation of hepatic tumors. Materials and methods: Deeply located HCCs (n = 5) and metastases (n = 3) in seven patients were included in this study and the lesions were histopathologically diagnosed by needle biopsy. The size of the tumors was 1.8 -3.8 cm (mean; 2.6 cm).

Under US guidance, the tumors were targeted with a 21 gauge needle and a 0.018 inch guide wire was inserted though the needle. A 7 F sheath with an inner 6 F introducer was inserted over the guide wire. Finally a 15 gauge RF needle with 7 expandable electrodes was placed through the sheath and RF thermal ablation of the tumors was performed. Results: All eight hepatic tumors were accurately targeted with the 21 gauge needle and a safe route for RF needle placement was ensured, avoiding major hepatic vessels. In five patients with HCC, the livers were shrunken due to cirrhosis but the procedure was performed without bleeding complications. Completely nonenhancing areas at the tumor sites were seen in all cases on immediate helical CT scans after RF ablation. Conclusion: Our results suggest that a new technique using a vascular sheath for RF needle placement under US guidance is safe and useful in the RF thermal ablation of hepatic tumors.

The necrotizing effect of direct injection of hot acetic acid in the liver in rats M. Nakai 1 , M. Sato 1 , N. Takeuchi 1 , H. Minamiguchi 1 , K. Yamada 1 , M. Kimura 1 , K. Kishi 1 , M. Terada 1 , N. Kawai 2 ; 1 Wakayama/JP, 2 Osaka/JP Purpose: To evaluate the effects and the safety of hot acetic acid injection therapy (PHAIT). Method and materials: Male Wistar rats underwent laparotomy and fluid was injected into the liver with a liquid heating device that allows injection of fluids at a designated temperature safely. The fluids injected were physiological saline at 50°C, 60°C, 70°C, 80°C, 90°C, and 100°C (n = 5); 5 %, 10 %, 15 %, 20 %, 30 %, and 50 % acetic acid at 30°C (n = 5); 10 % acetic acid at 50°C, 70°C, and 100°C (n = 5); and 20 % acetic acid at 100°C (n = 5). At 72 hours after injection, the mortality was examined and the liver was extracted and the volume of necrotic region was measured. Results: The mortality rate in the physiological saline group, 10 % and 20 % acetic acid groups was 0 %, but rates in the 30 % and 50 % acetic acid groups at 30°C were 20 % and 40 %, respectively. When each of hot physiological saline and hot acetic acid was injected, the region of tissue-necrosis enlarged with rising temperature from 60°C. The necrotic region also enlarged with rising concentration of acetic acid. The necrotic region obtained after injection of 10 % acetic acid at 100°C was almost the same as that obtained with 30 % acetic acid. Conclusions: The necrotic region induced by injection of low concentration acetic acid enlarged using a hot solution. In comparison with the high concentration acetic acid, hot 10 % and 20 % acetic acid solutions exhibited less acute toxicity. These results suggest a possibility of the safe use of hot acetic acid solution.

withdrawn by author C-0449 CT-guided lateral recess approach for the epidural injection of corticosteroid: Safety and efficacy H. Kang, C. Park, S.H. Lee; Seoul/KR Purpose: Epidural injection of corticosteroid for the treatment of pain and relief of sciatica and related conditions had been an established part of non-surgical therapy, but there is controversy internationally regarding its safety and efficacy. This study intended to find the proper approach to get close to the anterior epidural space and target nerves for increased efficacy and safety. Materials and methods: Since May 2001, 19 patients with sciatica and related conditions underwent CT-guided epidural lateral recess injection of corticosteroid. They were diagnosed by CT or/and MRI as disc herniation (protrusion or extrusion: 12 patients), spinal canal stenosis (2 patients) and relative spinal canal stenosis (5 patients). The side of approach was determined by the distribution of sciatica and/or site of herniation disc. We determined the technical errors and complications of this procedure. Results: We achieved access to the lateral recess and infused corticosteroid around target nerves in all patients. The patients were given 40 mg triamcinolone mixed with 5 ml of 0.5 % lidocaine using 20 gauge spinal needles. Dural puncture was seen in one patient, it was detected on an epidurogram, and we successfully accessed again. Complications and side effects; mild headache (1 patient), mild dizziness (1 patient), nausea (1 patient) and transient weakness of legs (6 patients). There was symptomatic improvement in 14/19 (74 %: excellent and good by Macnab's criteria) patients on clinical follow-up 2 weeks after treatment.

Conclusion: CT-guided lateral recess approach for epidural injection of corticosteroid provides a safe and reliable therapeutic option and increases the efficacy of the procedure.

Transcatheter embolization for pseudoaneurysms of common hepatic artery and its branches M. Okahara, H. Kiyosue, Y. Hori, K. Tomonari, R. Tanaka, Y. Yamada, S. Douno, S. Matsumoto, H. Mori; Oita/JP Purpose: To assess the efficacy and safety of transcatheter emobolization of pseudoaneurysms of the common hepatic artery and its branches. Material and methods: We have retrospectively reviewed 21 patients (17 males and 4 females, mean age 64.9 years) who underwent transcatheter emobolization of hepatic artery pseudoaneurysms caused by percutaneous transhepatic biliary dranage (n = 7), hepatic biopsy (n = 4), pancreatoduodenectomy (n = 3), cholecystectomy (n = 3) and others (n = 4). The aneurysms were located in the common hepatic artery (n = 3), right hepatic artery (n = 1), left hepatic artery (n = 1), segmental-subsegmental hepatic arteries (n = 10) and peripheral hepatic arteries (n = 3), gastroduodenal artery (n = 2) and posterior superior pancreaticoduodenal artery (n = 1). Embolic agents used were metallic coils, gelatine sponge or n-butyl-cyanoacrylate. 20 cases were treated by occlusion of the parent artery and one was treated by endosaccular packing of the pseudoaneurysm with coils. Results: Complete occlusion was observed in 20 of 21 cases angiographically immediately after embolization. Rebleeding was observed in 2 cases with pseudoaneurysms located in the common hepatic artery. In one of these 2 cases, one pseudoaneurysm was treated by endosaccular packing and another was treated by proximal occlusion of the parent artery. Two complications (one hepatic infarction and one acute ischemic cholecystitis) were observed after embolization. These complications and rebleeding occurred in the cases with the common hepatic artery pseudoaneurysms (3 of 4 cases). Conclusion: Although transcatheter embolization is generally thought to be a safe and effective method for hepatic pseudoaneurysms, it is still difficult to treat pseudoaneurysms of the common hepatic artery safely by this method alone.

Predictive evaluation of parasitic supply to hepatocellular carcinomas by multiphase dynamic CT Y. Okino, H. Kiyosue, S. Matsumoto, R. Takaji, Y. Yamada, Y. Hori, H. Hata, H. Mori; Oita/JP Purpose: Recurrent hepatocellular carcinoma (HCC) after transarterial infusion chemotherapy (TAI) with or without embolization often occurs with recruitment of a complex arterial supply, some of which arises from extrahepatic arteries (parasitic arterial supply: PAS) and will cause difficulties in re-treatment. In this study we investigate whether PAS can be detected on dynamic CT. Materials and methods: Medical records, dynamic CT scans and angiograms in ten patients with HCC having PAS were reviewed. 20 patients with HCC without parasitic supply were used as a control group. Evaluations were made of previous treatment, the location of the tumors and the detectability of PAS, including the right infraphrenic artery, the internal mammary artery and the left gastric artery on helical CT in both groups. When these arteries were detected, the site and maximum diameter were compared in both groups. Results: All HCCs with PAS had been previously treated with transcatheter methods. All extrahepatic arteries were detected on helical CT in patients with PAS, and 85 % of them were also detected in the control group. Their distal portion entering into the liver was visualized in all patients with PAS but was not in the control group except for two dilated infraphrenic arteries associated with interstitial lung disease. Conclusion: Helical CT can demonstrate PAS in HCC. Preangiographic recognition of PAS on dynamic CT affects the strategy for the treatment of the HCC.

CT-guided discogram of L-spine: Technique and usefulness H. Kang, C. Park; Seoul/KR Purpose: In most cases, L-spine discogram is acquired by using C-arm, and after the C-arm control, CT discography also becomes available when necessary. The purpose of this study is to define for usefulness and approach method of discogram under CT control. Materials and methods: Since May 2001, 29 patients (43 levels) with sciatica or/and back pain underwent a CT-guided discogram. We studied the relative safety and the reduction in invasiveness of this method under CT control and to see what advantage and usefulness this procedure has comparing with C-arm control for discogram. An interlaminar approach was used for L5 -S1 discograms, other levels were approached by a posterolateral method. Measurements of the angle and distance of how to approach the target point were performed on the CT images and then the needle was inserted in a parallel fashion, with a protractor ruler, keeping the angle constant. 10 patients were examined to detect foraminal or far lateral disc herniation and 19 patients were examined for pain provocation tests with fissuring. Results: 8/10 (80 %) patients were found to have foraminal (3 patients: with concordant pain provocation) and far lateral (5 patients: pain provocation occurred to only one patient with vague pain) disc herniation. 12/19 (63 %) patients had positive findings with fissuring from the pain provocation test. Conclusion: CT-guided discogram is a less-invasive procedure for perfroming discograms and it is one of the most accurate methods for detection of foraminal or far lateral disc herniation.

The efficacy of X-shaped metallic stent insertion in unresectable malignant biliary hilar obstruction as a new palliative method: Kissing or cross typepreliminary report S.-W. Yoon 1 , J.-S. Yu 2 , Y. Ryu 2 , M.-S. Park 2 , K. Kim 2 ; 1 Gangwon-Do/KR, 2 Seoul/KR Purpose: This study prospectively assessed the efficacy of X-shaped metallic stent insertion in unresectable malignant biliary hilar obstruction as a palliative method. Materials and methods: Two metallic stents were inserted, kissing (n = 6) or cross (n = 3) type X-configuration in nine patients with unresectable malignant biliary hilar obstruction. The causes of obstruction were cholangiocarcinoma (n = 7), gall bladder cancer (n = 1) and colon cancer metastasis (n = 1). First, percutaneous transhepatic biliary drainage (PTBD) was done in all patients. After several days, metallic stents were inserted, one of two types of X-shaped configuration at the obstructed site. Balloon dilatation of the obstructed site was performed before stent insertion in all cases. Patient survival and stent patency rates were estimated and complications with regard to the procedure were checked. Results: There were no technical failures in stent insertion. All but one patient returned to normal bilirubin levels after stent insertion. Only one showed a persisting high bilirubin level. Stent occlusion occurred in four patients. The causes of obstruction were sludge (n = 2), tumor overgrowth in the distal portion (n = 1) and thick mucin (n = 1). Seven of the nine patients died. The overall patency and survival rates were 228 days and 276 days, respectively. Hemobilia and pain developed during the procedure in all patients. These findings were related to balloon dilatation and resolved quickly. Conclusion: X-shaped metallic stent insertion is an effective palliative procedure in patients with unresectable malignant biliary hilar obstruction.

Endovascular treatment with a coronary stent graft (Jomed) of two intrahepatic arterial injuries M. Venturini, E. Angeli, M. Salvioni, F. De Cobelli, M. Napolitano, A. Del Maschio; Milan/IT Purpose: To report our preliminary experience in endovascular conservative treatment of two intrahepatic arterial injuries with a coronary stent graft. Methods and materials: Two patients with massive haemorrhage due to biliary resection for Klatskin tumour and blunt trauma were treated with a PolyTetraFluoroEthylene (ePTFE) covered stent ("Jostent coronary stent graft"). The stents were placed in the Right Hepatic Artery and in the distal part of the Proper Hepatic Artery/proximal part of RHA respectively to exclude a RHA iatrogenic pseudoaneurysm and a Left Hepatic Artery traumatic rupture. The stents were dilated by inflating a coronary-balloon (< 3 F) with a pressure of 16 atm. Ticlopidine (500 mg/day) and aspirin (300 mg/day) for 3 months and only aspirin (300 mg/day) indefinitely were administered. Stent patency and eventual signs of infection were evaluated with a Color Doppler examination after 3, 6 and 9 months. Results: Exclusion of the pseudoneurysm and the bleeding lesion was obtained with haemorrhage resolution. Regular stent patency was evident at 9 months, with no signs of infection. Conclusion: In iatrogenic or traumatic splanchnic arterial injuries, endovascular wall repairing with covered stents is a less invasive alternative to embolization: the use of the flexible coronary balloon-stent, smaller than peripheral devices also allows treatment of arterial injuries of small caliber vessels. In small caliber vessels, high-pressure balloon dilatation and prolonged antiplatelet therapy are strongly recommended to prevent stent graft restenosis. 

Interventional approach to abdominal hemorrhage M. Yamasaki 1 , A. Furukawa 1 , K. Maeda 1 , M. Takahashi 1 , K. Murata 1 , T. Sakamoto 2 ; 1 Otsu/JP, 2 Shiga/JP Purpose: Abdominal hemorrhage is an emergency that can be caused by trauma, neoplasm, inflammation, vascular disorders or iatrogenic means. With the development of equipment and techniques, the role of interventional therapy in this field has expanded. For variceal hemorrhage, endoscopic therapy, variceal embolization, TIPS or surgery can be performed. In this exhibit, the basic methods of selection of a treatment option for several forms of abdominal hemorrhage including characteristics of the embolic materials is described. Indications, complications and limitations of these procedures are discussed.

The clinical and radiographic records of 41 patients (17 with tauma and 24 with non-traunatic) who underwent emergency intervention over a 10-year period at our institution were reviewed. Results: The primary success rate in stopping hemorrhage with interventional techniques was 92.6 %. Cessation of hemorrhage can be obtained by the infusion of vasoconstrictive agents or gelatin sponge, or by the placement of metallic coils. A metallic stent-graft was used for hemorrhage from the vena cava in a case after a traffic accident. Conclusion: The selection of a method of treatment depends on the cause, severity and site of bleeding, and the knowledge of the indications for each method is essential for reliable and safe treatment.

Regional therapy of activation of the hepatic cirrhosis T.L. Pirtskhalava, D.A. Granov, I.O. Rutkin; St. Petersburg/RU Adequate transfusion therapy for patients with cirrhosis, especially with ascites, is limited due to overloading the right heart chambers with volume. The aim of our study was to search for new techniques enabling us to reach a maximum concentration of drugs by directly infusing into the liver small volumes. Material and methods: 11 patients with cirrhosis, B stage (6 patients) and C stage (5 patients) by Child-Pugh, underwent 13 courses of regional therapy. A catheter was left for 3 -5 days in the hepatic artery. An optimal compound of infusion media was determined comprising of 100 -150 ml 20 -30 % of glucose, 200 mg ascorbic acid, 400 mg inozini, 200 ml aminoacids with a branched chain, 100 ml fresh frozen plasma, 2.1 ml "Heparcompositum". Results: After regional therapy the index of cytolysis-alkalin phosphatase was reduced two-fold compared with the average; bilirubin and ALT were reduced by 37 and 40 %, respectively. A positive balance of diuresis was 430 (780 -315) ml/ day. Circumference of the abdomen was reduced by 5.7 cm on average with a stable body weight. There was a regression of peripheral edema. All patients subjectively felt an improvement of their general state. Conclusion: Regional therapy of the hepatic cirrhosis in the complex of treatment procedures enables to reach a reduction of activation within a short period and to decrease the duration of treatment. Objective: Cirrhotic patients are prone to septic episodes after creation of a transjugular portosystemic shunt (TIPSS). Aim of the study was to clarify whether an influx of bacteria from the portal venous system draining the gastrointestinal tract into the central venous blood system can be demonstrated. Material/methods: In 97 patients with portal hypertension TIPSS was created to treat varices after a bleeding episode or to reduce refractory ascites. Prospectively, microbiological analysis was performed on blood samples drawn in 20 of these patients from 1) a central venous line at the beginning of the procedure and 2) from the portal vein immediately after it was reached by transjugular access. 20 minutes after TIPSS creation, another sample of central venous blood was obtained. Results: With a technical success rate of 92 %, the mortality rate was 0 %. In 82 % of pts. no further bleeding episode was noted. Hepatic encephalopathy developed in 17 % with conservative treatment. Six patients had episodes of septicemia within 4 months after TIPSS that was fatal in 4. None of the blood cultures drawn were positive for Gram-positive or Gram-negative bacteria. Conclusion: TIPSS procedure is a safe and effective method to treat esophageal or gastric varices or refractory ascites due to portal hypertension. Bacterial infections with sepsis are a complicating condition after elective TIPSS procedure that may require prophylaxis. In this prospective series, no immediate bacterial washin from the gastrointestinal tract or exogenous/iatrogenic source during TIPSS procedure was found to explain this problem.

The usefulness of thoracic aortography after bronchial embolization H.J. Chun, B.G. Choi, J.Y. Byun; Seoul/KR Purpose: To evaluate the usefulness of thoracic aortography after bronchial artery embolization in patients presenting with hemoptysis. Materials and methods: We performed bronchial angiography and embolization followed by thoracic aortography in 69 patients (M:F = 47:22, mean age 43) who were admitted with a wide variety of degrees of hemoptysis between March 2000 and August 2001. The underlying diseases were also variable including tuberculosis, emphysema, aspergillosis, bronchitis, bronchiectasis and empyema. Initial bronchial angiography was performed with embolization, and all the arteries possibly causing hemoptysis, such as internal mammary, intercostal, lateral thoracic, thoracodorsal and inferior phrenic were then selected and embolized. After completion of embolization, thoracic aortography was performed with the catheter tip located at the top of the descending aorta. Result: A total 151 arteries (41 right bronchial, 33 left bronchial, 4 common bronchial, 59 intercostal, 5 inferior phrenic, 4 thoracodorsal, 4 internal mammary, 1 thyrocervical) were found and considered origins of hemoptysis in 69 patients. Of them, 23 arteries (15.2 %) were not detected on initial selection and embolization but found on post-embolization thoracic aortography. These included 2 right bronchial (5 %), 3 left bronchial (9 %), 3 inferior phrenic (60 %) and 15 intercostal arteries (25 %). Most of them were additionally embolized and the patients were discharged without significant recurrence of hemoptysis. Conclusion: The inferior phrenic and intercostal arteries are relatively frequently missed on routine arterial embolization in patients with hemoptysis. Post-embolization thoracic aortography is very useful in monitoring the effectiveness of embolization and excluding undetected arteries causing hemoptysis.

Care of patients undergoing radio frequency ablation (RFA) I.M. Bood Carlsson; Malmö/SE Purpose: To present a method to prevent thermal injuries under the grounding pads during RFA. Methods and materials: RFA is a method for treating malignant tumours. In our department we have performed 26 RFA procedures since February 2000. A needle, connected by a cable to a radiofrequency generator, is inserted into the tumour during ultrasound guidance. The produced energy is converted into heat from the non-insulated portion of the needle. At temperatures above 55°C there is severe protein coagulation and cell destruction. Two grounding pads are used. The pads should be placed over muscle tissue and not be placed in close proximity to implanted metallic prostheses, as they can become conductive. To reduce resistance between the skin and the pads the hair is shaved and the skin cleaned with alcohol. In addition, to reduce the heat, our group has started to place ordinary saline bags on top of the grounding pads. The saline bags are in advance cooled to a temperature of 2°C and fixed with an elastic net. Results: During the first ten procedures the grounding pads were not chilled and during these seven thermal injuries occurred under the pads; one of these was a third degree burn. Since we started to chill the grounding pads with cold saline bags, no thermal injuries have occurred. Conclusion: Thus, chilling the grounding pads with cold saline bags seems to be an effective method to prevent thermal injuries during RFA. 

DSA images were obtained automatically on the multimodality workstation. Two neuroradiologists analyzed the characteristics of the aneurysm; size, shape, direction, neck and the relationship to adjacent vessels. Results: 3D DSA images clearly demonstrated the characteristics of all 59 intracranial aneurysms. It was especially effective in depicting aneurysms with a posterior projection, complex bilobulated or irregular shapes, broad necks and dysplastic walls. It was also useful in the determination of a working view for endovascular treatment and the evaluation of residual aneurysm after surgical or endovascular intervention. Conclusion: 3D-DSA could be a valuable tool for the pre-and post-treatment evaluation of intracranial aneurysms.

Comparison of accuracy of extemporary cyto-diagnostics during fine needle aspiration cytology (fnac) cyto-assistance and final results in 3051 cases of radiologically-guided transcutaneous biopsies G. Ciarmiello, U. Sannini, A. Rabassini, G. Zamburlini, M. Ronzon, L.E. La Torre, C. Cultrera, G.F. Granieri; Treviso/IT Purpose: Literature on the subject shows that FNAC is frequently considered the first choice method for defining the benign or malignant nature of a tumor. For best results from radiologically guided aspiration there must be continuous, real cooperation between the radiologist and cytopathologist. The advantages of "cyto-assistance" are discussed, the main aim of which is to check the adequacy of the material taken from each puncture. The aim of this work is to investigate the accuracy of extemporary cytological diagnosis.

The study took into consideration 3051 FNAC obtained over the last 18 years and divided as follows: 1380 pulmonary, 1450 hepatic and 221 pancreatic. The extemporary cytological specimen was stained with rapid MGG, while the final diagnosis was carried out on material fixed in 95% ethyl alcohol and stained with hematoxylin-eosin. Results: There was a greater than 95 % agreement between the extemporary diagnosis and the final diagnosis. Conclusion: Extemporary diagnosis, which only has an indicative value and is basically concerned with defining benignity or malignancy, is useful in practice to accelerate the diagnostic process, for example staging.

The usefulness of real-time smoothed mask DSA (RSM-DSA) for vascular mapping for right gastric artery embolization M. Tsuda, T. Matsuhashi, T. Yamada, H. Saito, T. Ishibashi, S. Takahashi; Sendai/JP Purpose: Right gastric artery (RGA) embolization reduces the incidence of gastric mucosal lesions associated with repeated hepatic arterial infusion chemotherapy. The purpose of this study was to assess the usefulness of real-time smoothed mask DSA (RSM-DSA) for vascular mapping of RGA embolization. Methods and material: RSM-DSA is a mulit-directional DSA method (SHIMADZU Medical Systems), which is a subtraction of an unsharped mask image from a live image obtained alternately during one acquisition. RSM-DSA permits C-arm movement during exposure for the short interval (33 ms) between live and mask images. Common hepatic angiography using RSM-DSA in the precession movement was undertaken in 26 patients with metastatic liver tumors to define the origin of the RGA. Image intensifier (I.I.) position in the precession movement was divided into 4 segments (cranial (CRA), right anterior oblique (RAO), caudal (CAU) and left anterior oblique (LAO) projection) to estimate the optimal angle of view. Result: Using RSM DSA in the precession movement, the origin of RGA was easily detected. RGA arose from proper hepatic artery (38 %), left or middle hepatic artery (29 %), gastroduodenal artery (25 %) and common hepatic artery (8 %). Retrograde catheterization via the left gastric artery revealed RGA arising from the gastroduodenal artery in only one case. The optimal angle of view was LAO in 43 %, CRA in 26 %, CAU in 17 % and RAO in 14 %. RGA embolization was technically successful in 24 of 26 patients (92 %). Conclusion: C-arm motion with RSM-DSA allows multi-directional angiography. Especially in the precession movement, it is useful for vascular mapping for RGA embolization.

Preliminary experience of percutaneous transhepatic peritoneo-venous shunts for treatment of refractory severe ascites K. Kuroki, K. Takizawa, Y. Nakajima; Kawasaki/JP Purpose: A peritoneo-venous shunt was created percutaneously and transhepatically in two patients for treatment of refractory severe ascites. A report of their initial findings is provided. Subjects and methods: A catheter was inserted into a hepatic vein through the jugular vein. Then a communication between the hepatic vein and intraperitoneal space was made using a hard guide wire and a catheter for infusion therapy was placed between the hepatic vein and intraperitoneal space to form a shunt for treatment in these two cases of refractory, severe ascites accompanying hepatoma and cirrhosis. Results: Although one of the cases demonstrated a remarkable reduction in abdomen size and was able to walk in the hospital after having initially been bedridden, the patient died approximately 3 weeks later due to pneumonia. The other case had poor renal function, and although the abdomen size decreased considerably following dialysis, the patient became dialysis dependant and died approximately 1 month later due to renal failure. Conclusion: A percutaneous transhepatic peritoneo-venous shunt has the potential to contribute to an improvement of QOL of patients with refractory severe ascites.

Chemoembolization in neoadjuvant treatment of bone and soft tissue sarcomas L.B. Vashkevich, J.V. Zalutsky, V.S. Dudarev, V.V. Akinfeyev; Minsk/BY Purpose: To enhance the efficacy of neoadjuvant treatment for limb-sparing surgery of patients with locally advanced bone and soft tissue sarcomas. Materials and methods: 26 patients with locally advanced extremity bone sarcomas (T2N0M0G2-3) and soft tissue sarcomas (T2N0M0G2-3) were administred 1 to 3 preoperative courses of neoadjuvant multidrug chemotherapy with local hyperthermia and chemoembolization of the tumor-feeding arteries using doxorubicin and cisplatin. Results: All patients had alleviation or elimination of pain. Three to four weeks after the treatment, the tumor was reduced by 50 to 99 % in 20 patients (77 %) and by 33 to 49 % in 5 patients (19 %). One patient (4 %) reported disappearance of the tumor (100 %). After the completion of neoadjuvant therapy, 23 patients underwent surgery. Limb-sparing surgery was performed in 18 (78.3 %) patients. Five (21.7 %) patients with osteosarcomas of the distal femur had their limb amputated because of tumor involvement of the knee joint, pathological fracture and skipmetastases to the femur. Three patients refused surgery. Histological examination of the ablated tumors detected grade III pathomorphism in 7 (30.5 %) patients and grade I -II in 15 (65 %). Histological examination was not performed in one patient (4.5 %) because of disappearance of the tumor. Conclusion: Chemoembolization in combination with thermochemotherapy in neoadjuvant treatment produced a significant regression of the tumor, which optimized the conditions for limb-sparing surgery of patients with musculoskeletal sarcomas. 

(16 %) cases, the internal thoracic artery was embolized in 3 (0.9 %), the phrenic artery in 15 (4.4 %) and the intercostal artery in 10 (2.9 %). The hyperthermic procedures caused no complications. Conclusion: TACE and its combination with hyperthermic manipulations is an efficient and safe treatment for hepatic malignant tumors.

Uterine artery embolization with gelfoam in the treatment of uterine fibroids D. Ovtcharenko, V. Verkhovski, M. Belikova; St. Petersburg/RU Purpose: To evaluate the effectiveness of uterine artery embolization with gelfoam in the treatment of fibroids. Materials and methods: 21 patients (aged 27 -42 years; mean 38.2 years, all desiring to preserve fertility) with refractory vaginal bleeding and/or chronic pelvic pain relating to uterine leiomyomata underwent bilateral uterine artery embolization with gelfoam pledgets. Clinical improvement was assessed at 2 -9 months (mean 5.8 months) after the procedure. Sonographic measurments of the uterus and dominant masses were obtained before and at three months after the procedure. Results: All 21 patients underwent technically successful embolization. Complete resolution of symptoms was observed in 13 patients and 7 patients reported noticeable symptomatic improvement. A large reduction in uterine volume (average 35 %) and dominant fibroid size (average 65 %) were sonographically demonstrated. There were no complications necessitating surgery. Conclusion: Early and midterm results of fibroid embolization with gelfoam are similar to those reported for polyvinyl alcohol particles.

Arterial embolization for bleeding pseudoaneurysms complicating pancreatitis D. Ovtcharenko, V. Verkhovski; St. Petersburg/RU Purpose: To evaluate the efficacy of arterial embolization in the management of bleeding from pancreatic artery pseudoaneurysms complicating pancreatitis. Materials and methods: Celiac and superior mesenteric angiography with subsequent transcatheter embolization of ruptured peripancreatic pseudoaneurysms was performed in 11 patients with major bleeding (gastrointestinal n = 2, abdominal n = 9). Pseudoaneurysms of the splenic artery (n = 4), gastroduodenal artery (n = 2), pancreatoduodenal artery (n = 4) and left inferior phrenic artery (n = 1) were the source of bleeding in these patients. The embolization technique was dependent upon the site of arterial hemorrage and the ability to selectively catheterize the vessel. Different coil occlusion devices was used in all cases. Results: Cessation of flow into the pseudoaneurysm and hemodynamic stability was achieved in 10 cases (91 %). Complications occured in one patient (splenic infarction). In one patient embolization of the bleeding vessel failed because of its incomplete occlusion with coils and he underwent surgery. There was no recurrence of bleeding. Surgery was needed in four patient for nonhemorrhagic complications of pancreatitis. Conclusion: The effectivness of arterial embolization is very high and allows avoidance of surgery in hemodynamicaly unstable patients.

Real-time compound imaging: Improved sonographic guidance during TIPSS procedure? A. Saleh, M. Cohnen, R. Lüthen, A. Scherer, L.W. Poll, U. Mödder; Düsseldorf/DE Purpose: To compare the visibility of different TIPSS puncture needles using realtime compound imaging (SonoCT) and single-line ultrasound (SLU). Methods and materials: Two 18 G Ross-puncture needles (Portacaval Nadel, Bard Angiomed, Karlsruhe, Germany; Echocoat needle, Cook, Bjaeverskov, Denmark) were placed into a cadaverous liver in a water bath at four different angulations (0, 30, 45, 60°). Sonography was performed with an ATL HDI 5000 sonography device with a 2 -5 MHz convex array using single-line ultrasound and compound imaging. Images of the needles were obtained in the longitudinal plane without changing depth, focus position or gain settings between measurements. The mean grey scale values of the needle tip (gvn) and of the background (gvb) were obtained from histograms. Contrast was calculated using the equation (gvn − gvb)/gvn + gvb). Results: At 0° visibility of the needle is good, even with SLU (0.622). For all scanning techniques no significant difference could be observed between coated (0.565) and uncoated (0.567) needles (p = 0.87). At 30° the visibility of the needle is dramatically diminished. With SonoCT the contrast was significantly higher (0.370) compared to SLU (0.301) (p < 0.05) but no difference could be observed between coated and uncoated needles. At 45° and 60° the needle tip was not visible with all scanning techniques. Conclusions: The visibility of the needle is strongly dependent on the angulation. Contrast is enhanced with real time compound imaging, but it is still low for steeper angulations.

Rapidly-heparin-releasing and heparin-adherent angiographic catheters: In vivo and in vitro assessment of anti-thrombogenic effect J. Han, K. Lee, C. Yoon, Y. Byun, H. Moon, B.-I. Choi; Seoul/KR Purpose: We evaluated the effectiveness of two types of novel anti-thrombogenic angiographic catheters, rapidly-heparin-releasing and heparin-adherent catheters.

We developed rapidly-heparin-releasing catheters by coating polyurethane catheters with a blend of amphiphilic heparin-derivative (heparin-deoxycholic acid) and hydrophilic hydrogel block copolymer. Heparin-adherent catheters were developed by coating with a blend of hydrophobic heparinderivative (heparin-octadecylamine) and organic solvent. For in vitro assessment, a platelet aggregation test and a fibrin formation test were performed with both types of heparin-coated catheters and non-coated catheters (as control) and the results were interpreted using scanning electron microscopy. For in vivo assessment, five pairs of coated and control catheters (5 French) were prepared for each type of heparin-coating system. Coated and control catheters were inserted in both femoral arteries at the same time in an anesthetized mongrel dog and clamped for 30 minutes after aspiration of 10 cm 3 of blood. After removal, each catheter was flushed with 20 cm 3 of saline on filter paper and the mass of fresh thrombi was measured. Results: On in vitro assessment, neither platelet aggregation nor fibrin formation was observed in both types of heparin-coated catheters compared to strong reactions on the control catheters. On in vivo assessment, the mass of thrombi from rapidly-heparin-releasing (0.148 ± 0.020 g, mean ± SD) or heparin-adherent (0.118 ± 0.022) catheters was less than that from the control catheters (0.235 ± 0.023 and 0.245 ± 0.014, respectively) in all pairs (p < 0.05 and p < 0.05, respectively, Wilcoxon matched-pairs signed-ranks test). Conclusion: Both types of new anti-thrombogenic angiographic catheters were effective in vitro and in vivo.

Percutaneous transpulmonary CT-guided liver biopsy: Alternative approach for evaluating subphrenic lesions of the liver L. Thanos, G. Papaioannou, A. Nikita, A. Sissopoulos, E. Alexopoulou, D.A. Kelekis; Athens/GR Purpose: To determine the feasibility and effectiveness of percutaneous transpulmonary CT-guided liver biopsy in subphrenic lesions of the liver. Materials and methods: The files of 852 patients who underwent CT-guided liver biopsy in our institution were retrospectively studied. In 42 patients (28 males and 14 females, aged between 39 to 89 years) the biopsy needle was advanced to the liver lesion though a transpulmonary route. The diameter of the lesions ranged between 2.0 to 5.5 cm (mean 3.1 cm). 18 G automated core biopsy needles with a 2 cm cutting-edge were used in all cases. Results: 39/42 biopsies yielded diagnostic tissue specimens (92.8 %). Lesions were identified according to biopsy results as hepatocellular carcinomas (n = 21), metastatic (n = 17; from colon Ca n = 12/17, pancreatic Ca n = 3/17, breast Ca n = 2/17) and hemangiomas (n = 1). No major complications were observed. A small pneumothorax, identified in 2 patients, resolved uneventfully. Conclusion: Percutaneous transpulmonary CT-guided liver biopsy with 18 G biopsy needles represents a safe and effective alternative for tissue sampling from subphrenic lesions of the liver.

Vertebroplasty in metastases from breast cancer -66 cases J. Chiras, A. El Khairi, E. Cormier, M. Rose; Paris/FR Vertebroplasty is a technique of interventionnal radiology which had been developed to obtain local pain relief and stabilize vertebral hemangiomas. Its usefulness in the treatment of vertebral metastases has been previously reported. We present our results in 66 patients suffering from metastases from breast cancer: 132 vertebras where treated (cervical 16, thoracic 63, lumbar 53). 13 patients were treated for recurrence of pain after local treatment including surgery and/or radiation therapy. 53 patients were treated at the first step of the treatment of the vertebra involved by vertebroplasty eventually in combination with surgery or radiotherapy.

A significant analgesic effect was obtained in most cases (84 %) but was often incomplete in cases of multi-focal disease. Stabilization of vertebra was observed in 93 % of cases with a mean follow up of one year. The morbidity rate was very low (< 4 %)and consisted of transitory postoperative radicular pain, no neurologic deficit was observed.

Graft-covered polar renal arteries after endovascular AAA repair with suprarenal fixation K.S. Malagari, E.N. Brountzos, A. Skoulariki, R. Mastorakou, D.A. Kelekis; Athens/GR Purpose: To determine the effects of covering the ostia of polar arteries (by covered graft) at AAA exclusion on renal function. Material and method: 5 polar arteries were evaluated in 4 patients offered suprarenally fixated stent-grafts. In one patient, lower pole arteries existed bilaterally. The inferior polar artery of another patient gave rise to the gonadal artery. These polar arteries supplied less than 30 % of the renal parenchyma. Two other patients underwent embolization of their supernumerary arteries. These polar arteries supplied more than 30 % of renal parenchyma. An Endologix device was used in those 2 patients. A Zenith device was used in the remainder. Follow-up included spiral CT angiography at one and six months post intervention followed by annual examinations. Blood urea and creatinine levels were also measured. Results: No type II endoleak was observed (concerning the 3 polar arteries that had not been embolized). The polar artery that gave off the gonadal artery remained patent the 1 st month after intervention but thrombosed over the next 5 months. The other polar arteries were occluded the 1 st month post intervention. Renal function was not compromised in any of the cases. No renal infarct was observed. Conclusion: It is generally thought that polar arteries must be embolised to avoid type II endoleaks, however, no such endoleak was observed in our cases. The occlusion of the polar arteries does not cause renal function impairment or renal infarction. Results: Selective catheterization failed in seven PAVMs, four were located in the left upper lobe. Two coils were misplaced, one was removed and one occluded a segmental instead of a subsegmental artery without any consequence. A younger patient complained of a severe chest pain 3 and 8 months after PTE. Two out of the 5 PAVMs, in which occlusion was incomplete, were complex. Two patients experienced temporary, strange hemi-corporal sensation during selective treatment of a PAVM previously partially occluded. Tiny fistulas not occluded at first, in one patient who still had occlusion of multiple PAVMs, increased in size and required a third procedure. Conclusion: Coils-PTE appears safe. However rare, the possibility of misplacement of coils makes it necessary to occlude the largest fistulas with the largest feeding arteries first, to avoid dangerous coil migration. If non invasive imaging demonstrates residual flow, coil-PTE can be completed without new selective opacification, to avoid embolic neurological disorders.

Efficacy of gastric blood supply redistribution by preoperative transarterial embolization for esophageal carcinoma: Experience in 100 cases Y. Mori 1 , S. Itoh 1 , S. Akiyama 1 , K. Takai 1 , T. Ota 1 , T. Isomura 2 , K. Maruyama 3 , A. Nakao 1 , T. Ishiguchi 1 , T. Ishigaki 1 ; 1 Nagoya/JP, 2 Nakano/JP, 3 Yokkaichi/JP Purpose: We proposed previously a new procedure of preoperative redistribution of gastric blood supply by transarterial embolization to prevent anastomotic leakage following surgical reconstruction of the esophagus for esophageal carcinoma. The aim of this study was to validate the efficacy of the procedure. Materials and methods: In one hundred patients with esophageal carcinoma, preoperative transarterial embolization of the left gastric, right gastric and splenic arteries was consecutively attempted with coils so that the gastric blood supply was dependent only on the right gastroepiploic artery. Based on the post-embolization angiographic findings, opacification of the left gastroepiploic artery via the right gastroepiploic artery was assessed. Reduction in the gastric tissue blood flow during preparation of a gastric tube was measured. Results: Embolization of the left gastric, right gastric, and splenic arteries was successfully performed in 91 of 100 patients. The left gastroepiploic artery filled via the right gastroepiploic artery in 87 of 91 successful embolizations. During operation, the color of the gastric tube was good and the reduction in gastric tissue blood flow was 30 % on average in patients with successful embolization. Minor anastomotic leakage occurred in only 4 patients. Conclusion: Preoperative redistribution of gastric blood supply by embolization resulted in the dilation of the anastomosis from the right to the left gastroepiploic artery and helped prevent anastomotic leakage following esophageal reconstruction by reducing the drop in the gastric tissue blood flow during preparation of a gastric tube.

Hepatic artery chemoembolization in patients with liver metastases from neuroendocrine tumors R. Garcia Mónaco, H. Bertoni, G. Pallota, O. Peralta, P. Briggs, J. Lastiri, M. Varela, S. Ballester; Buenos Aires/AR Objective: To evaluate response, survival and toxicity in patients with liver metastases from neuroendocrine tumors (NET) treated with hepatic artery chemoembolization (CE). Patients and methods: 122 CE procedures were performed in 43 patients with liver metastases from NET. Selective arterial transcatheter infusion with a lipiodoldoxorubicin mixture was followed by selective embolization. Primary tumors consisted in 29 carcinoids, 4 islet cell tumors, 3 gastrinomas, 2 vipoma, 2 glucagonomas, 1 mixed and 2 undetermined. Localization was gastrointestinal in 40 %, pancreatic in 30.5 %, sacral in 2 % and unknown in 27.5 %. Mean age was 56 (range 29 -81 years) Results: Synchronous presentation of liver metastases was observed in 17 patients. In 4 cases surgical metastasectomy was performed. 20 patients received systemic chemotherapy and 23 octeotride. In all patients with secreting tumors a humoral response was achieved, 74 % had a complete response. Symptomatic response was observed in 88 % of all patients. 19 % showed a complete radiological response, 70 % partial and in 11 % no radiological response was observed. Median survival was 56.6 months from diagnosis and 31.46 months from treatment. One patient presented with a hepatic abscess as a procedure related complication, 2 patients presented with a confusional syndrome and 1 developed posttreatment hypertension. Conclusion: Hepatic artery CE is a safe, effective and well-tolerated procedure in the treatment of unresectable, symptomatic liver metastases from NET, providing excellent symptomatic, humoral and radiological response.

Endovascular reconstruction of type B dissections and aneurysms of the thoracic aorta R. Garcia Mónaco, H. Bertoni, O. Peralta, J. Da Silva; Buenos Aires/AR Purpose: To evaluate immediate and short term safety and effectiveness of an endovascular prosthesis placement procedure in type B thoracic aortic dissection and aneurysm. Materials and methods: Between September 1999 and June 2001, 16 patients underwent treatment (11 male and 5 women) with a mean age of 55 years (range: 42 -78 years) with a diagnosis of thoracic aneurysm (n = 5), type B dissection (n = 10) and penetrating ulcer (n = 1). Preoperative studies were spiral CT (n = 16) and digital angiography (n = 5). Endoprostheses were placed via access from the femoral artery and were released via an endovascular approach in the operation room under controlled hypotension. Mean follow up was 10 months with a range of 2 to 22 months, and was performed in all patients with Spiral CT. Results: Placement of an endoprosthesis was technically satisfactory in all patients. During follow up, complete exclusion of the dissection and thrombosis of the aneurysm sac was shown in 15 of 16 patients. No migrations or endoleaks were registered. Complications were stroke (n = 1) and GI bleeding that led to death (n = 1). Conclusion: Endovascular treatment of Type B dissections and thoracic aortic aneurysms is safe and effective in the short term. Refinement of the endoprostheses, a higher number of patients and long term follow up will be necessary to determine the exact role of this attractive therapeutic modality. To evaluate the effectiveness of percutaneous treatment in the treatment of multiple liver hydatid cysts. Methods and materials: Percutaneous treatment was performed in 40 hydatid cysts (24 type I, 15 type II, 1 type III) in the livers of 5 patients (3 female). The patients had 4, 4, 5, 7 and 20 liver hydatid cysts. PAIR technique was preferred for cysts smaller than 100 ml whereas larger cysts were catheterized. 27 cysts (68 %) were treated using PAIR technique and 13 cysts (32 %) were treated with catheter drainage and ethanol sclerotherapy. Results: Major complications (mortality or intraabdominal spillage) were not observed. The volume reduction was between 52 -94 % of the initial volume (mean 75 %). After treatment, cysts transformed to remnants with minimal fluid (32 cysts), to remnants without fluid (4 cysts) and to remnants with partial calcification (4 cysts). No recurrence was observed during follow up. Follow up periods of the 5 patients were 5, 3, 9, 1 and 1 year respectively Conclusion: Percutaneous treatment of multiple liver hydatid cysts is a safe and effective method as an alternative to surgery and medical treatment.

Hemorrhagic complications of renal interventional procedures: Usefulness of selective embolization R. Garcia Mónaco, G. Rosa Diez, H. Bertoni, O. Peralta, E. Dos Ramos Farias, S. Algranatti; Buenos Aires/AR Purpose: To communicate our experience in selective embolization of hemorrhages related to percutaneous renal interventional procedures. Materials and methods: Between 1991 and 2001, 19 patients were referred to our Division with severe hemorrhage following percutaneous renal procedures (biopsy: 11; litothripsy: 3; endopielotomy: 3; nephrostomy: 2). 6 of 19 patients had a single kidney. Mean age was 44 years (range: 15 -84). All patients received initial medical treatment. Failure of this therapy lead to referral for angiography and selective embolization. Embolic agents used were cyanocrilate (n = 9), spongostan (n = 6), PVA microparticles (n = 4) and coils (n = 2). Two patients received cyanocrilate as well as coils. Results: Renal angiography detected 29 iatrogenic vascular lesions: 18 pseudoaneurysms and 10 arteriovenous fistulas. In one patient there was associated renal infarction. In all cases the vascular lesion was successfully occluded with selective embolization. Bleeding ceased in all patients without following complications. Conclusion: Selective embolization is highly effective (100 % in our series) and safe in stopping severe hemorrhage produced by interventional renal procedures.

Usefulness of extracranial Doppler ultrasound in monitoring treatment of brain arteriovenous malformations with endovascular embolization M. Anton-Jozwiakowska, M. Szajner, T. Jargiello, W. Krzyzanowski, M. Szczerbo-Trojanowska; Lublin/PL Purpose: Assessment of extracranial Doppler ultrasound in monitoring hemodynamic changes of blood flow in patients after endovascular embolization. Material and method: 20 patients with brain AVMs were examined. In 16 cases, AVMs were located supratentorially and in 4 cases infratentorially. In 9 patients AVMs were supplied by the internal carotid artery, in 5 cases by the vertebral artery and in 6 cases by both arteries. In 6 cases the AVM nidus was 6 cm. In total 45 embolization procedures were performed. Doppler examinations were performed before and after each embolization. Flow velocity, PI and RI were calculated in both ICAs and VAs. Results: In 14 cases of AVMs > 3 cm in diameter PI and RI values were reduced in feeding vessels. In 9 of these cases an increase in flow velocity was also detected. In these patients progressive increases in resistance indices were detected after every stage of embolization. In 6 cases with AVM < 3 cm we found no difference in measured Doppler parameters. Conclusions: Doppler examination is helpful in monitoring endovascular embolization treatment of brain AVMs with a nidus > 3 cm.

Preoperative portal embolization to induce hypertrophy of the future remaining liver R. Garcia Mónaco, H. Bertoni, O. Peralta, F. Acuña, E. De Santibañes, M.M. Buzzi; Buenos Aires/AR Purpose: To report our experience in Preoperative Portal Embolization (PPOE) in order to induce hepatic regeneration and hypertrophy of the future remaining liver. Materials and methods: Between 1999 and 2001, 10 PPOE procedures were performed. The procedure was indicated when a large hepatectomy was needed for complete excision of the tumor, resulting in an increased risk of postoperative hepatic insufficiency. 54 % of the patients were female. Mean age was 52 years (range: 30 -73). Tumors were primary in four patients and secondary in 6. Preoperative evaluation consisted of abdominal ultrasound, Spiral CT with liver volumetry and direct portography. PPOE was performed by selective catheterization of each intrahepatic portal branch with distal occlusion. The intervention was performed percutaneously under ultrasound guidance in 3 cases, or at laparotomy with catheterization of a colic vein in 7 patients. Embolization material employed was cyanocrilate mixed with ultrafluid lipiodol in a proportion of 1:1. Patients underwent a follow-upCT scan 4 weeks after the procedure, to evaluate hypertrophy. Results: Portal embolization was technically successful in all cases. The average volume increment of non embolized hepatic segments was 128 cm 3 ± 30 cm 3 , which is equivalent to a 35 % growth in volume of the future remaining liver. In 3 patients, tumors could not be removed because of progession of the disease and the remaining 3 patients underwent surgery. Conclusion: Selective portal embolization enables contralateral liver hypertrophy, thus decreasing the incidence of postoperative liver failure. This method makes it possible to resection hepatic tumors previously considered unresectable. Purpose: Acute limb ischemia following thrombosis of a popliteal aneurysm is a distinct, limb-threatening clinical entity. Preoperative, in-situ thrombolysis improves outcome. The present study analyses, retrospectively, a consecutive series of patients with lysis and subsequent revascularization. Patients and methods: Thirteen patients with acute limb ischemia related to a thrombosed popliteal aneurysm underwent in-situ thrombolysis with urokinase and subsequent vascular reconstruction. Arteriography and clinical outcomes were analyzed and compared to the literature. Results: Complete aneurysm thrombosis without runoff was documented in twelve cases. Thrombolysis restored perfusion with patency of the popliteal artery and one or two vessel runoff in 77 %. Early graft patency and limb salvage were respectively 66 % and 83 %, with an ankle/brachial index of 0.8 ± 0.2. Lytic failure followed by attempts at bypass grafting occured in three patients (23 %) and resulted in above-knee amputation. Severe rhabdomyolysis and fatal pulmonary embolism were responsible for a 15 % early mortality. Conclusion: Preoperative thrombolysis followed by bypass grafting seems to be the treatment of choice for acutely thrombosed popliteal aneurysms in patients who can withstand an additional period of ischemia. Lytic failure identifies patients with highly compromised runoff probably best treated by subsequent amputation without attempts at bypass grafting.

Percutaneus drainage of pancreatic pseudocysts into the stomach P. Popovic, M. Surlan, M. Sever, D. Vidmar, K. Surlan; Ljubljana/SI Purpose: Evaluate five years of results of percutaneous ultrasonographically guided internal cystogastric drainage of symptomatic pancreatic pseudocysts. Methods: From September 1995 to September 2000, percutaneous drainage of pancreatic pseudocysts was performed in 21 patients. There were 16 males and 5 females with an average age of 48 years. The medium diameter of the pseudocysts was 12 cm. Biliary etiology of pancreatitis was found in 11 cases, alcoholic in 9 cases and in one case the origin was unknown. 16 patients had already undergone previous surgery for pancreatic pseudocysts. The procedure was performed under local anaesthesia.

Results: The procedure was successful in all 21 patients. The catheter was removed endoscopically 5 to 14 months after intervention. In one patient the catheter was removed spontaneously by peristalsis (6 months after intervention). Complications occurred in 5 patients. In three cases the pseudocyst reappeared early after catheter removal. In two of these three cases, the catheter was introduced again in the same way (no sign of pseudocyst recurrence on further follow-up). Three patients underwent an operation, one because of reappearance of a pseudocyst and two because of early drainage complications. After 5 years in 18 patients, clinical and ultrasonographical follow-up showed a successful treatment. In 16 patients the primary procedure was satisfactory and in 2 patients a secondary procedure was needed. Conclusion: This method is minimally invasive, save and effective. We believe that percutaneus drainage is an important component of the range of methods used to manage patients with symptomatic pseudocysts due to chronic pancreatitis. Materials and methods: During a period of 2.5 years, nine patients (from 27 to 84 years old, mean 50 years) were treated percutaneously for a significant non-tumoral SVCS. Symptomatic SVCS were due to dialysis catheters (7), central line (1) and radiation therapy (1). In thrombotic occlusion and severe stenosis in-situ thrombolysis was achieved prior to stenting. Patients were followed-up with echo-Doppler, CTA, MRA and phlebography. Results: Complete recanalization of the veins was obtained in all patients, with no venous injury. There were no procedure related complications such as hemorrhage, pulmonary embolism, local or distant infection. Symptomatic SVCS resolved in all patients. Thirteen stents were placed in nine patients with a mean clinical follow-up of 9.1 months (range 2 -23 months). 100 % primary patency and assisted patency rates at 6 months were obtained. Two patients recurred twice and were treated with new stent placements. The 12 months primary patency was 75 % and the assisted secondary patency was 100 %. No stent migration was seen. Conclusions: Stent placement in non-tumoral symptomatic SVCS is a safe and minimally invasive procedure, with no technical or clinical complications in our experience. It allowed immediate relief of symptoms, and in dialysed patients can provide continued use of hemodialysis access. Close clinical surveillance is mandatory to assess stent patency.

The role of CT-guided biopsy of lymph nodes from various anatomic sites A. Nikita, L. Thanos, G. Papaioannou, K.S. Malagari, M. Papathanasiou, D.A. Kelekis; Athens/GR Purpose: To evaluate the feasibility of CT-guided Percutaneous Needle Biopsy (PNB) and Fine Needle Aspiration Biopsy (FNAB) to obtain diagnostic tissue from lymph nodes. Materials and methods: From May 1998 to October 2000, 78 lymph node biopsies from various anatomic sites were performed in 78 patients. The male to female ratio was 46:32 and the mean age was 52.3 years. 31 patients with mediastinal lymph nodes, 27 patients with paraortic lymph nodes, 15 patients with iliac lymph nodes, 2 patients with deep cervical lymph nodes and 3 patients with lymph nodes at the porta hepatis underwent CT-guided PNB (n = 61) or FNAB (n = 17). For the FNA, a fine needle (20 G) was used and for the PNB a super core needle (18 G) was used. Results: The obtained tissue was sufficient to establish the diagnosis in 59 of 61 (96.7 %) PNBs and in 9 of 17 (52.9 %) FNABs. In two patients (3.3 %), PNB samples were inadequate for pathological examination, while in 8 patients (47.1 %), FNAB samples were inadequate for cytological examination. The diagnoses were lymphoma (n = 41), carcinomatous lesion (n = 17) and inflammatory lesion (n = 3). No major complication was observed. A small pneumothorax and haemoptysis were recorded in one and two patients, respectively. Conclusion: CT-guided biopsy of lymph nodes from various anatomic sites is a safe procedure which provides useful diagnostic information in the majority of cases.

Subclavian artery atherosclerotic lesions: Treatment with angioplasty and stents M. Cantasdemir, F. Kantarci, M.H. Yilmaz, B. Kara, F. Numan; Istanbul/TR Purpose: The purpose of this study was to evaluate the results of angioplasty and stenting of subclavian artery atherosclerotic lesions. Methods and materials: 20 patients (16 male, 4 female) with a mean age of 56.7 (range 40 -74) years underwent percutaneous treatment of 23 subclavian artery lesions. The major presenting symptoms were ischemic complaints in the involved upper extremity in 15, subclavian steal in 8 and vertigo in 7 cases. Angiographically there were 22 stenoses with a mean stenosis rate of 75.2 % (range 50 -95 %) and 1 occlusion. All the angioplasty and stenting procedures were undertaken via the femoral artery route. In 7 of the lesions stenting was performed with a mean stent length of 44 mm (range 13 -80 mm) and angioplasty was performed using balloon dilation catheters of varying sizes (range 5/20 -10/40 mm) in 16 lesions. A postprocedural anticoagulation protocol included Aspirin and Dipiridamol. Results: Percutaneous angioplasty resulted in complete dilation of the stenotic segment in 12 of the lesions. In 4 lesions there were residual stenoses ranging from 15 to 35 %. In 7 stenting procedures, restoration of luminal patency was achieved in 6 lesions. In one lesion there was a 15 % residual stenosis. All the patients responded well to stenting and angioplasty procedures and they were followed-up clinically. The mean follow-up time was 36.4 months (range 1 -90 months).

The results of this series indicate that stenting and percutaneous angioplasty of subclavian artery atherosclerotic lesions appears safe and feasible with good short and mid-term patency rates.

Percutaneous right portal vein embolization before major hepatectomy for liver metastases of colorectal cancer M. Greget, J. Tongio, C. Leveque, E. Oussoultzoglou, P. Bachellier, D. Jaeck, F. Veillon; Strasbourg/FR Purpose: To evaluate the results of right portal vein embolization (RPVE) to induce hypertrophy of the healthy liver before extended right hepatectomy. Methods: 18 patients presenting with liver metastasis from colorectal cancer underwent RPVE. Metastases were unilobar or bilobar in 10 and 8 patients respectively. RPVE was performed using enbucrilate (n = 15) or PVA and coils (n = 3). Results: 12 patients underwent hepatectomy: right hepatectomy and right hepatectomy extended to segment IV in 5 and 7 patients respectively. Estimation of the hepatic volume was achieved with 3D CT. The mean volume of the future left remnant liver was 447 cm 3 (160 -670 cm 3 ) before and 584 cm 3 (216 -1150 cm 3 ) after RPVE. The mean hypertrophy was 65.2 % (42 -117 %). One severe complication was noticed: extensive portal vein thrombosis. The reasons for surgical abstention (n = 6) were: metastatic extension (n = 3), poor hypertrophy (n = 2), portal thrombosis (n = 1). 

Conclusion: RPVE induces significant hypertrophy of the future remnant liver and increases the feasibility of major right hepatectomy in patients with liver metastases from colorectal cancer.

Outcome of percutaneous transluminal angioplasty for renovascular hypertension in children M.A. Barkovics 1, 2 , R. Davies 2 , I. Gordon 2 , M. Dillon 2 ; 1 Budapest/HU, 2 London/GB Purpose: Retrospective review of children with reno-vascular hypertension treated by renal artery angioplasty (RA-PTA). Evaluating the angiographic appearances before and after RA-PTA with respect to clinical outcome. Materials and methods: 22 children's 25 kidneys were treated with a total of 30 RA-PTA procedures. The mean age was 9.5 years. The renal artery stenoses were graded angiographically from 1 to 7 with 1 being less than 25 % stenosis and 7 being occluded. The improvement after angioplasty was calculated as the PTA score. The clinical outcome was scored from 0 to 3 (0 = no improvement, 3 = normotensive without medications). Results: The stenosis grade pre-PTA was 4.27 ± 1.01 (i.e. over 75 %), post-PTA was 2.50 ± 1.60 (i.e. 50 %). 88 % of children became normotensive at follow-up, 21 % without any medication, 50 % on less drugs and 17 % on the same regimen of medication. The improvement in stenosis grade was a better predictor of clinical outcome than the actual degree of residual stenosis. Conclusions: In this series, although there was only a modest morphological improvement seen on angiography, the majority of children became normotensive. In children with renal artery induced hypertension, all stenoses > 50 % in main or branch arteries can be considered for RA-PTA on the basis of poor control of blood pressure despite adequate trials of medication.

A. Pedicelli 1 , C. Di Stasi 1 , A. Cina 1 , F. Di Gregorio 1 , M. Rollo 1 , A.R. Cotroneo 2 ; 1 Rome/IT, 2 Novara/IT Purpose: The increased use of interventional procedures and the frequent use of central venous catheters have contributed to a relative increase in the occurence of intravascular foreign bodies (FB). Their retrieval is justified to prevent potential, related complications. A high morbidity is related to surgical retrieval, especially in the case of intravenous FB (often located in the heart or pulmonary arteries), this has contributed to the increased use of percutaneous retrieval procedures. Methods and materials: We report our experience in 40 patients presenting with a FB [intravenous (iv) in 35 cases and intrarterial (ia) in 5]. Retrieval was usually performed with a snare-loop catheter (36 cases) together with a pig-tail catheter in 10 cases and also with a Dormia basket in 4 cases (together with a snare-loop in 1). A percutaneous transfemoral approach was performed in most cases and we used 6 -7 F introducers that were retrieved together with the FB when the latter was brought out at the femoral site. Results: Percutaneous retrieval was successful in all the iv cases and in 2 ia cases. The other 3 ia cases required surgical removal under local anesthesia after percutaneous hooking and displacement of the FB to a more accessible site. No major complications were observed during retrievals. Conclusions: Based on our results, and in agreement with the literature, we believe that percutaneous retrieval should be considered the treatment of choice for FBs. The procedures success depends on an accurate diagnostic approach, good knowledge of materials and techniques and the operator's experience, as well as the possibility of an interdisciplinary collaboration between radiologist, surgeon and anesthesist.

LDR-irradiation, interventional and hyperthermic possibilities in nonoperable bile duct tumors Z. Vígváry, Z. Tarján, Z. Dömötöri, G. Tóth, K. Kiss, E.K. Makó; Budapest/HU Purpose: Our purpose was to demonstrate the feasibility of a combined interventional radiological and intraluminal radiation treatment in patients with obstructive jaundice caused by malignant masses. Methods and materials: In 12 patients, with obstructive jaundice caused by nonoperable cholangiocarcinoma originating from the common bile duct, the following palliative treatment was applied: after percutaneous biliary drainage intraluminal Cs 137 irradiation with LDR after loading was applied (32 Gy, 24 h). The irradiated lumen was stented via a percutaneous, transhepatic approach placing a double endoprothesis. Locoregional electrohyperthermy was applied in all patients after stenting.

The intervention was well tolerated and ensured free bile flow. The patients died due to the progression of the disease 14 -23 months later, free of jaundice. Conclusions: We conclude that intraluminal irradiation, in combination with biliary percutaneous intervention, is a feasible and promising treatment to increase the efficacy of palliative percutaneous drainages in patients with obstructive jaundice caused by malignant masses.

Technique of laser assisted, CT-guided biopsies J. Jessurun, W. Obermann; Leiden/NL Purpose: To illustrate our guidelines on how to perform laser assisted CT-guided biopsies in order to obtain a good biopsy yield. Materials and methods: A spiral CT scanner (Philips AVE) with fluoroscopy mode (Biopsy view) and a Targo laser beam and different biopsy systems (Jamshidi, Tru-cut or FNA systems) were used. In addition, a location grid, local anaesthetic and proper sterile conditions were used. Patients were properly instructed and positioned on the table in such a way as to ensure maximum comfort for the patient and easy access to the lesion. Breathing instructions are most important. After preliminary slices through the region of interest with a location grid, the best route, angle and depth to the lesion to be biopsied were determined and a biopsy taken. Results: In our institution 190 patients underwent 209 biopsies (1999 -2001) . 19 biopsies were repeated, either because there wasn't enough material to reach a diagnosis or because the biopsied material was thought not to be representative. 12 of these repeat biopsies gave a diagnosis. 14 complications occurred: 8 hematomas and 6 pneumothoraces of which one pneumothorax needed therapeutic intervention. Conclusion: Laser assisted, CT-guided biopsy is a safe and accurate way to obtain histologic material either to reach or to complete a diagnosis. The procedure is stepwise and visually explained. Various tricks will also be stressed. The overall biopsy yield in our instution reached 93 % per total biopsy attempts and 96.3 % per total patients.

Brachytherapy for the prevention of neointimal hyperplasia in the canine inferior vena cava after stent placement M. Isota, T. Kamiou, Y. Sakai, N. Nisida, S. Tanaka, T. Ninoi, K. Nakamura, R. Yamada; Osaka/JP Purpose: To evaluate the efficacy of γ brachytherapy for preventing neointimal hyperplasia in the inferior vena cava (IVC) after stent placement. Materials and methods: Sixteen beagles underwent Z-stent placement in the IVC and aorta in same animals simultaneously. For 8 of 16 beagles, γ irradiation (15 Gy) was delivered endoluminally to the stented segments of IVC and aorta immediately after stent placement using a 192 Ir source. For the remaining 8, only stent placement was performed as a control group. Angiography was performed 6 weeks later. Then all animals were sacrificed, the stented segments were examined histopathologically and analyzed morphometrically by measurement of neointimal thickness. Results: Morphometric analysis showed the neointimal thickness of the IVC in the irradiated group was significantly decreased compared with the control group as well as that in the aorta (p < 0.05). Histopathologic findings showed the neointima of the IVC in the control group to contain marked organization of thrombus and neovascularization whilst that in the IVC and aorta of the irradiated group consisted mainly of smooth muscle cells. No damage occurred in the native wall and adjacent tissues of the stented segments. Conclusion: High dose rate intravenous irradiation with 192 Ir effectively inhibited neointimal proliferation after stent placement. This data suggests that intravenous irradiation therapy may prevent clinical restenosis after stent placement.

Transcatheter treatment of duodenal varices T. Ninoi, T. Kaminou, Y. Sakai, M. Isota, S. Tanaka, N. Nishida, K. Nakamura, R. Yamada; Osaka/JP Purpose: To evaluate the efficacy of transcatheter treatment in patients with duodenal varices. Materials and methods: Five patients presenting with duodenal varices due to portal hypertension were treated with different embolization techniques to prevent variceal bleeding. In all patients, 5 % ethanolamine oleate with iopamidol (EOI) was used as the embolic material. Two patients underwent dual balloon-occluded embolotherapy (DBOE) after placement of two balloon catheters in the anterior

superior pancreaticoduodenal vein and duodenocaval collaterals. One patient underwent balloon-occluded retrograde obliteration (B-RTO) after placement of the balloon catheter in the duodenocaval collaterals. In one patient, modified percutaneous transhepatic obliteration (m-PTO) was carried out from the pancreaticoduodenal vein. In this patient, placement of multiple microcoils was required to reduce the flow within the varices prior to embolization with EOI. In one patient, variceal bleeding occurred despite former transjugular intrahepatic portosystemic shunt (TIPS). To prevent further bleeding m-PTO was performed. After treatment, efficacy was evaluated by endoscopy. Results: The technical success rate of transcatheter treatment was 100 % (all 5 patients). In four of the 5 patients, the duodenal varices disappeared, and in one of the 5 patients they decreased. All of the 5 patients were controlled by transcatheter treatment. There were no major complications. Conclusion: Transcatheter treatment should be considered very safe and effective for duodenal varices.

Treatment of intermetatarsal neuromas with alcohol injection under US guide S. Masala, E. Fanucci, V. Varrucciu, R. Fiori, A. Romagnoli, G. Simonetti; Rome/IT Purpose: Aim of this study was to evaluate intralesional treatment of intermetatarsal neuroma's with alcohol sclerosing injection as a viable alternative to steroid injections or surgery in persisting symptoms. The cause of intermetatarsal neuroma is unclear; the pathogenesis is most likely induced mechanically by degenerative neuropathy or entrapment of the intermetatarsal nerve under the transverse intermetatarsal ligament. Materials and methods: 40 patients with clinical symptoms of intermetatarsal neuroma underwent from 3 to 7 applications at 7 to 10 day intervals of a solution of 30 % alcohol sclerosing injections under US guidance, with no other conservative or surgical treatment. Results: A complete resolution of all symptoms was achieved in 90 % of the patients. Conclusions: Treatment of intermetatarsal neuromas includes very simple methods, like changing shoe styles or more complex conservative treatments such as orthotic devices and steroid injections and ultimately surgical therapy.

Percutaneous high frequency induced thermo therapy (HITT): Effectiveness in different liver lesions M. Jaworski, B. Pruszynski; Warsaw/PL Purpose: To compare the hyper-echogenic zone around the needle tip observed during coagulation in real time US and power Doppler withthe area of necrosis on follow-up examinations: CT, MRI, US in different hepatic lesions. Materials and methods: 18 patients (10 males and 8 females) aged 28 -76 years old (mean 48.4) with unresectable malignant liver nodules: 6 (33 %) hepatocellular carcinoma, 4 (22 %) cholangiocarcinoma, 5 (28 %) colorectal metastasis and 3 (17 %) endocrine metastasis were treated with repeated percutaneous high frequency induced thermo-therapy with perfused needle applicators (HiTT, Berchtold). Assessment of the coagulation area was recorded during the procedure with US and power Doppler. Treated tumors were reobserved after 2, 4 and 8 weeks by means of spiral CT, MRI and US. The size of the necrotic area was compared with the hyper-echogenic zone. Results: Correlation between the area of complete necrosis and the hyperechogenic zone: for hepatocellular carcinoma ±8 mm, for cholangiocarcinoma ±17 mm, for colorectal metastasis ±5 mm and for endocrine metastasis ±21 mm. Conclusion: Preliminary results of this trial showed a good correlation in hepatocellular carcinoma and colorectal metastasis but a relatively poor correlation in cholangiocarcinoma and endocrine metastasis.

Endovascular embolization of bleeding visceral pseudoaneurysms with platinum coils and N-butyl cyanoacrylate M. Parildar, A. Memis, I. Oran; Izmir/TR Purpose: To evaluate the efficacy of transcatheter embolization in visceral artery pseudoaneurysms with platinum coils and n-butyl-cyano-acrylate (NBCA). Materials and methods: Over the past seven years 20 patients were treated by transcatheter embolization in the same sitting with diagnostic angiography. Four right hepatic, one cystic, two gastroduodenal, one cavernosal artery, three superior mesenteric artery branch and eleven renal artery branch pseudoaneurysms were included in the study.

: Surgery was completely avoided in 19 patients. In the remaining patient with a superior mesenteric artery branch pseudoaneurysm, endovascular embolization was unsuccessful. Eighteen pseudoaneurysms were thrombosed with coil embolization alone. The remaining three pseudoaneurysms needed NBCA embolization. Two patients died from sepsis within 5 weeks after embolization. Conclusion: Emergent diagnosis and treatment is essential in visceral artery pseudoaneurysms because of the high rate of death. Transcatheter embolization with platinum coils is an efficient, safe treatment of choice. NBCA may be used to avoid proximal embolization of the visceral arteries which could not be selectively catheterized due to tortuosity, vessel size or anatomical location.

Intentional rotation of stent-grafts with longitudinal struts during endovascular treatment of aortic aneurysms: Experience in two cases K.-L. Hajeck, R. Fischbach, A. Kippels, F. Korsten, C. Mueller-Leisse; Mönchengladbach/DE Purpose: Our aim was to find out if intentional rotation of stent-grafts with longitudinal struts has an impact on the risk of stent breakage in endovascular treatment of aortic aneurysm with severe aorto-iliac kinking. Material and methods: Two male patients, one 70 and the other 78 years old, presented with infrarenal aortic aneurysms and severe aorto-iliac kinking of more than 80°. As there was a high risk for surgical treatment in both patients, we decided to treat the patients with stent-grafts notwithstanding the severe kinking. In order to prevent breakage of the longitudinal struts, we planned to rotate the stentgrafts, such that the longitudinal struts were orientated 90° and nearly 180° respectively to the level of kinking. Results: Rotation of the stent-graft was successfully performed in both cases with the longitudinal struts demonstrating a gentle curve and a good adaptation to the vessel anatomy. Conclusion: Intentional rotation of stent-grafts is feasible. It may be indicated in patients with infrarenal aortic aneurysm even if kinking is severe.

Stent placement in renal artery stenosis: Palmaz-Corinthian stent experience A. Memis, M. Parildar, I. Oran; Izmir/TR Purpose: Percutaneous dilatation is the first alternative therapy for renovascular hypertension due to renal artery stenosis which does not respond to medical therapy. In this study, the clinical outcome of balloon expandable (Corinthian) stenting was assessed in patients with renovascular hypertension due to renal artery stenosis. Materials and methods: Between January 2000 and May 2001, 32 patients with renal artery stenosis were treated with 39 Corinthian stents. Six patients had bilateral stenoses and were stented bilaterally. 29 patients had atherosclerosis, 2 patients had fibromuscular dysplasia and one patient had Takayasu arteritis. The indication for stenting was insufficient dilatation after percutaneous transluminal angioplasty in all patients. Results: Immediate technical success was achieved in all patients without any complication. Mean follow-up time was 12 months (3 -18 months). On follow-up, renovascular hypertension was cured or improved in all patients. One patient who had restenosis 4 months after stenting was treated with stent in stent placement. Conclusion: Corinthian stent implantation in renal artery stenosis is easy, safe and effective. It can be used in complex atherosclerotic and ostial stenoses primarily or after insufficient percutaneous transluminal angioplasty.

Current management of complex biliary hilar structures: A pictorial review and retrospective analysis of 11 cases C.M. Hartigan; London/GB Introduction: Non-surgical management of unresectable, complex, malignant, hilar strictures via percutaneous insertion of metallic biliary stents is a recognised procedure. ERCP is often unsuccessful and inappropriate in such cases. MRCP is invaluable in allowing assessment of complex strictures and demonstrating the extent of segmental duct involvement prior to percutaneous intervention. It identifies the level of stricture, characterizes the cause and helps to provide additional information necessary for therapeutic planning. Multiple stents reduce the incidence of cholangitis from potentially undrained segments. Methods: From March 1999 to February 2001, 11 patients with complex, malignant, hilar obstruction were palliated with multiple percutaneous endoprostheses. Previous MRCP was obtained in 9 cases. The underlying diagnoses included colorectal metastases (4), cholangiocarcinoma (4), gallbladder carcinoma (1), hepatocellular carcinoma (1) 

Results: All patients had successful procedures with a total of 37 stents (5 males, 6 females). Complications occurred in 3 patients including infection (3)and bleeding (2). Stent occlusion requiring reintervention occurred in only 2 cases (mean time 9.5 months). The 30-day mortality rate was 18 % with a mean survival of 5.8 months (range 2 weeks to 23 months). Conclusion: Management of complex hilar strictures is difficult. MRCP is invaluable in assessing and planning procedures. Extensive intrahepatic ductal involvement makes PTC preferable to ERCP. Multiple stents may be required to alleviate jaundice, symptoms and eradicate sepsis.

Percutaneous endoluminal stent graft placement for the treatment of femoro-popliteal aneurysms D. Lagana', R. Prudenzano, M. Marras, M. Mangini, R. Beretta, P. Castelli, C. Fugazzola; Varese/IT Purpose: To assess the efficacy of percutaneous endoluminal stent-grafts for the treatment of isolated femoro-popliteal aneurysms (FPA). Methods and materials: Between September 1998 and June 2001 9 FPA 2.5 and 5 cm (mean 3.7 cm) in diameter were treated. In all cases a covered self-expanding flexible stent (Wallgraft) was used using a percutaneous approach and a 9 -10 F introducer. Patients were followed up with Color-Doppler at 1, 3, 6, 12 and 24 months after intervention (the mean value of follow-up was 10.5 months). Results: All the stent grafts were successfully implanted without either thromboembolic or bleeding complications. Stent-graft occlusion was observed in 3 patients one month after the procedure: two cases were successfully recanalized with local fibrinolysis therapy; one case was converted to open surgery. Color-Doppler demonstrated stent graft (primary and secondary) patency and aneurysm exclusion in 2/8 cases up to 24 months, in 2/8 up to 12 months and in 4/8 up to 3 months (three patients with the shorter follow-up died for reasons unrelated to the endovascular procedure). Conclusion: In our small series the percutaneous therapy of FPA with covered stents appears to be an effective treatment modality. Nevertheless, further experience and longer follow-up is required to evaluate the role of percutaneous stent grafts in FPA.

Percutaneous transcatheter embolization of splanchnic artery aneurysms and pseudoaneurysms: A report of 12 cases A. Pedicelli 1 , C. Di Stasi 1 , G.E. Vallati 1 , A. Cina 1 , M. Rollo 1 , A.R. Cotroneo 2 ; 1 Rome/IT, 2 Novara/IT Purpose: We present our experience with endovascular embolization therapy in 12 cases of splanchnic artery aneurysm. These were located in 5 cases in the hepatic artery, 3 in the splenic artery, 2 in the gastroduodenal artery, 1 in the celiac trunk and 1 in the superior mesenteric artery. This pathology must be treated promptly because of the high risk of rupture, with complications such as hematemesis, hemobilia and hemoperitoneum. Methods and materials: Two patients had true aneurysms and ten patients presented with pseudoaneurysms; 5 were iatrogenic, 3 post-traumatic, 3 atherosclerotic-inflammatory and 1 mycotic. The diagnosis was made by CT and/or sonography. Seven patients had life-treatening intestinal bleeding; in 2 cases the diagnosis was made at emergency DSA. Five patients showed transpapillary bleeding, four of whom presented with hemobilia and one patient had bleeding into the pancreatic duct due to a true aneurysm of the splenic artery. Embolization was performed using a coaxial microcatheter coil delivery system (5 cases) or was performed with Hystoacryl (7 cases). 1 year follow-up in 8 patients and 6 months follow-up in the last 4 cases was performed with color-Doppler-sonography and/or CT. Results: In all patients complete occlusion of the aneurysm was achieved without surgical intervention. No immediate major complications occurred during or after the procedure. Follow-up demonstrated complete exclusion of the aneurysms in all cases. Conclusion: In our experience percutaneous embolization appears to be the safest therapeutic approach in the treatment of this pathology. Surgery has a mortality rate of 12 -50 % and should only be performed when embolization fails or is not feasable.

Percutaneous bone tumor management A. Gangi, S. Guth, J. Imbert, J.-L. Dietemann; Strasbourg/FR Purpose: To report our experience of various percutaneous techniques in the management of bone tumors with the aid of a multimedia presentation.

Between January 1993 and March 2001, over 500 patients with bone tumors including metastasis, myeloma and osteoid osteoma were treated in our department. Results: First, different techniques are described, such as alcoholization, cementoplasty, radiofrequency ablation and laser photocoagulation. Further, the indications and contraindications of each technique are discussed. Lastly, their advantages, limits, and results are outlined. Conclusion: There is a large spectrum of percutaneous techniques in bone tumor management. We describe the best indications, the results, advantages and limits of each technique based on a series of over 500 patients.

Radiofrequency liver tumor ablation with a novel wet electrode under CT and ultrasound guidance A. Gangi, S. Guth, J. Imbert, C. Roy; Strasbourg/FR Purpose: To demonstrate the use of simultaneous saline interstitial infusion at the tip of the electrode through side holes during ablation. Material and methods: 109 liver tumors were treated with radiofrequency ablation with a wet electrode under simultaneous control of impedance and temperature (Berchtold®, Tuttlingen, Germany). The study included 39 colorectal metastases, 12 breast cancer metastases and 58 hepatocellular carcinomas. The 18 to 16 gauge electrodes contain a coaxial lumen that enables a saline interstitial infusion (1 ml/min, 40 W during 10 min). Results: Ten days after the procedure the patients underwent a MRI scan. Complete tumor necrosis was achieved in 88 % of cases with an average of 1.9 treatment sessions per tumor. The mean lesion size measured was 4.4 ± 0.8 cm after a single treatment. In one case a major complication occurred, of a hepatic abscess, 4 weeks after the procedure in a cirrhotic patient. Conclusion: The wet electrode technique increases the total electrode surface area with improved thermal and electrical conductivity. This method allows avoidance of desiccation and impedance rises and allows treatment of larger lesion sizes. Also with the low electrode cost, this coagulation method proved to be very cost efficient as well as easy to use.

Compact navigation system dedicated to percutaneous interventions guided by CT: Advantages and limits A. Gangi, S. Guth, X. Buy, C. Roy; Strasbourg/FR Purpose: To evaluate the use of a multi slice CT unit and the utility of a navigation system for interventional procedures. Material and methods: 125 interventional procedures were performed with a multi slice CT unit (Somatom Plus 4, volume Zoom, Siemens) associated with a compact navigation system (CT-Guide 2000, Ultraguide, Triate Hacarmel, Israel). The navigation system consists of an image-based navigation tool using a real-time magnetic tracker comprising a transmitter unit and magnetic sensors. A spiral CT is performed and the data is transferred to the CT-guide navigator. Another small sensor is fixed to the needle. The position and the trajectory of the needle are projected in real time onto the acquired CT images. This enables real-time, in-slice or out-of-slice tracking of the needle without radiation to the patient or to the operator. Respiratory gating is provided. The system can be adapted to all spiral CT systems. Results: With the navigation system, successful positioning was achieved at the first insertion (deviation ≤ 2 mm) in 59 % of cases. In 32 % of cases a deviation of less than 5 mm was observed and in 9 % of cases the localization was impossible (patient motion or needle bending). Multi slice CT imaging allows localization of the needle tip within one CT setting in 95 % of cases. Conclusion: This technique, based on the association of a compact electromagnetic navigation system with a multi slice CT, is a safe, accurate and easy to use method for CT guided interventions with a substantial reduction in the radiation dose.

Percutaneous vertebroplasty set for easier and safer glue injection A. Gangi, S. Guth, A. Roche, J.-L. Dietemann; Strasbourg/FR Purpose: To describe, with the aid of a multimedia presentation, a dedicated vertebroplasty set for a safer and easier glue injection, increasing the precision and reducing complications. Material and methods: Percutaneous vertebroplasty is an effective treatment for diseased vertebral bodies. The acrylic glue is injected in the vertebral body during its pasty polymerization phase to avoid major complications. The injection time

Interventional Radiology available is about 3 to 5 minutes and the glue is injected with three to four 2 ml syringes. The set is composed of 10-to 15 gauge needle-wings and a cementogun screw applicator of 10 ml. Results: The needle is designed with side wings for an easier rotation and removal. The screw system allows direct aspiration of the glue without any manipulation thus reducing the risk of contamination. The screw syringe increases the precision of injection without hyper-pressure. No excessive effort is required. In this way, the glue can be injected progressively over an extended period of time. The risk of leak is substantially reduced. The system is safe, reduces the manipulation of the glue and allows excellent control of the injection. The needle-wings allow easy insertion, rotation and removal of the needle. 130 vertebroplasties were performed with the system without major complications. 

Percutaneous right portal embolization (with selective embolization of the IV segment in 8 cases) was performed in 14 patients (8 males and 6 females; mean age 61) in which the preoperative remaining liver volume (at Spiral CT volumetry) did not allow safe hepatectomy. 6 patients had metastases, 2 hepatocellular carcinoma (HCC) while 6 had hilar cholangiocarcinoma. A right portal vein approach was obtained in 12 patients while in 2 we perfomed a left approach. Complete embolization was achieved after selective catheterization with a 3 french coaxial system, injecting a mixture of Lipiodol and surgical glue. Results: In 10 patients (71.4 %) an increased left liver volume (from 2.7 % to 21.4 %; mean 8.7 %) was achieved during a mean time interval of 37 days (from 20 to 62 days) allowing surgical resection. In our series the best hypertrophy was obtained when embolization of the segment IV was performed. Surgery was not feasible in 4 patients (28.6 %) with metastatic disease (2 patients), HCC (1 patient) and hilar cholangiocarcinoma (1 patient) due to poor clinical conditions. Conclusions: PPVE is a safe and feasible procedure that allows surgery in patients with an initial small liver volume. It can fail in patients whose clinical conditions deteriorate during the time interval necessary for hypertrophy.

Complications of TRUS-guided prostate biopsies P. Zoumpoulis 1 , I. Theotokas 1 , A. Plagou 1 , A. Stefanaki 2 , P. Tsagaraki 3 , A. Papanikolaou 1 , D. Triantafyllou 1 ; 1 Kifissia/GR, 2 Samos/GR, 3 Iraklion/GR Purpose: To estimate the number and type of complications of prostate biopsies and indicate the techniques that can help avoid them. Materials and methods: A retrospective study of 5890 cases in a 6-year period was performed. All patients were contacted one day and one week following the day of the biopsy, so that all complications were recorded. The use of oral antibiotics prior and after the biopsy and patient preparation with a cleansing enema are two important factors in the limitation of prostate infection and septicemia. Results: Practically all patients presented with mild hematuria that lasted a few days and/or mild hemospermia that lasted several weeks. Also in all patients a periprostatic hematoma of variable size developed but had no clinical significance. In this work we expose our experience of treating liver tumors with RF, emphasizing the RF technique, complications, results and follow-up. Since 1999 we employed RF as a minimally-invasive method to treat hepatic lesions. We treated 80 lesions (45 metastases and 35 HCC, mean size 3.5 cm, range 1.2 -6 cm) in 59 patients. All the cases were treated under intraoperative (44 metastases and 9 HCC) or percutaneously (1 metastasis and 26 HCC) using a sonography approach. We used a 15 G needle with expandable curved electrodes placed into the tumor (Radiotherapeutics, Mountain View, CA) in 64 lesions and a straight internally cooled tip (Radionics, Burlington, MA) in the remaining lesions. A single ablation procedure took from 10 to 50 minutes depending on size, location (relationship with liver vessels), tumoral vascularization and the device employed. Follow up was performed with biphasic helical CT and also with enhanced color-Doppler sonography in HCC. The response was variable depending on tumor size, with complete tumor necrosis in 95 % of lesions under 3 cm. Decreased effectiveness was seen in larger lesions. Fortunately partial necrosis or intrahepatic recurrence can be successfully managed with repeat ablation (5 cases of HCC required a second session). In 14 cases of metastases, a combined (resection and RF) treatment was applied. The rate of tumor recurrence following RF also varies with tumor type and the follow-up duration being better in HCC than in metastases. In our experience, RF results in an efficient, minimally invasive method of treating liver tumors specially HCC, with short-time survival rates that rival those achieved with surgery with the benefit of lower morbidity. 

In 1999 a controlled, parallel, randomized clinical study was undertaken at our hospital. The inclusion criteria were women with bleeding caused by uterine fibroids who were candidates for hysterectomy. We excluded those who wished to maintain fertility, those with fibroids larger than 10 cm and those with surgical contraindications or an allergy to iodine-contrast. They were randomly assigned by the Zelen's Method: The informed group had the option of choosing UAE or hysterectomy. The hysterectomy group were not informed of UAE. The allocation ratio was unequal. 

Results: The success rate for cessation of bleeding was 86.1 %. The hospital stay was shorter for UAE by 4.14 days (intent to treat analysis). There was no difference in the number of readmissions. The percentage of patients with complications was higher in the UAE gruop, but the complications were more serious in the hysterectomy patients. Finally, there was a significant difference in the time it took patients to return to their activities of 26 days in favor of UAE. Conclusions: Although the efficacy of UAE was 86.1 %, this is a cost-effective and safe treatment in our health-care system, when compared with hysterectomy. For these reasons, UAE should be offered as an alternative treatment, if the only other option is hysterectomy.

Use of endovascular bifurcated stent-graft: Our experience A. Spinelli, C.A. Reale, S. Fabiano, T. Lupattelli, R. Gandini, G. Simonetti; Rome/IT Purpose: To describe our experience in the use of endovascular stent-grafts. Material and methods: Since October 1997 we have treated 123 pts (108 men, 15 women, mean age 72 years) with AAA. We also treated three patients as an emergency who had been previously treated with a surgical aortic graft: 1 aortocaval fistula, 1 aorto-enteric fistula and 1 rupture of an anastomotic pseudoaneurysm. We used 122 bifurcated grafts; 32 Van guard II (Boston Scientific USA), 5 Talent (World Medical USA), 85 Excluder (Gore) and 1 straight Endologix prosthesis. All patients were followed-up with X-ray, eco-color-Doppler US and Angio-spiral-CT. The CT follow-up was performed on post-procedural day 7, at 1, 3, 6 and 12 months and then every year after the procedure. Results: Immediate success was seen in all the patients. Follow-up showed the aneurysmal sac decreasing in size in 71 pts (57.7 %), stationary dimensions in 49 cases (39.9 %) and an increasing in size in 3 pts (2.4 %). There were 7 type I leakages (5.7 %) demonstrated at Spiral-angio-CT follow-up, 3 proximal (2.4 %) and 4 distal (3.3 %). Type II leakages did not occur. Surgical conversion was necessary in 3 pts (2.4 %). Conclusion: The endovascular treatment of abdominal aortic aneurysms is a safe and encouraging procedure with low complication rates if performed in selected patients. An accurate follow-up is important to reduce complications and leakage. The use of bifurcated endografts is also indicated in emergency cases and this endovascular treatment is fast becoming part of standard procedure.

Latrogenic ureteral injuries: Reconstruction with a rendez-vous technique C.A. Reale, T. Lupattelli, A. Spinelli, R. Gandini, G. Simonetti; Rome/IT Purpose: Evaluation of the efficacy of combined percutaneous-endoscopic reconstruction of iatrogenic ureteral lesion by double-J catheter stenting. Material and methods: Five patients between February 1996 and December 1999 underwent plastic stent positioning using a combined technique. All the patients were treated with a double approach (percutaneous and endoscopic) because the distal ureter could not be reached through a nephrostomy tube. A previous ureteroscopy had demonstrated the presence of ureteral transection in four patients and ureteral ligation in one. We advanced a guidewire in the retroperitoneum under cystoscopic guidance, then it was captured with a goose-neck snare (advanced from the nephrostomy) and retracted through the proximal ureteral portion and into the kidney. After ureteral continuity was restored with a wire, we placed a double-J catheter and decided to keep a nephrostomy in-situ for three days. Result: No contrast leak was noticed in any patient. The mean catheter duration was six months. We changed the double-J catheter in two patients after three, eight and nine months. Two other patients died from their underlying neoplastic pathology before the plastic stent could occlude. One patient is still alive without any symptoms. Conclusion: Due to its high success rate, this combined technique can be consider as a valid alternative to surgical ureteral repair.

Endovascular stent-graft repair in the management of late aortic surgery complications T. Lupattelli, R. Gandini, A. Spinelli, C.A. Reale, E. Pampana, G. Simonetti; Rome/IT Purpose: To describe two clinical cases; the first is a case of secondary aortocaval fistula and the second a case of secondary aortoenteric fistula, both treated by endovascular stent-implantation under local anesthesia. Methods and results: Case 1: A 67 year old man, who had undergone repair of a ruptured abdominal aortic aneurysm with a spontaneous aortocaval fistula with a 16 mm Dacron tube graft one month prior, presented with clinical features of con-gestive heart failure, lower extremity swelling and renal failure. Imaging showed an arteriovenous communication between the abdominal aorta at the distal anastomosis of the graft and the inferior vena cava. The use of endovascular exclusion of the fistula was proposed because of a high operative risk. Aortic endografting was performed using a Vanguard II bifurcated aortic stent-graft. Hemodynamic stability was restored. The fistula was excluded and no communication between the aorta and vena cava was seen on CT imaging follow-up. Case 2: A 68 year old man with multiple comorbidities, who had undergone aortoaortic grafting for aneurysmal disease 4 years previously was admitted to the emergency department with sudden gastrointestinal tract hemorrhage needing emergency treatment. Imaging showed a pseudoaneurysm between the anterior wall of the aorta at the distal anastomosis of the graft and the enteric tract. Owing to the patient's high surgical risk, an Excluder II stent-graft was implanted to exclude the fistula. Gastrointestinal hemorrhage ceased. Conclusion: In emergency situations, in high risk patients who have previously had aortic surgery, endovascular exclusion of aortocaval or aortoenteric fistulas is a possible treatment option that avoids problems encountered in conventional repair. Purpose: To describe and illustrate the usefulness of a 3D-TSE sequence including driven equilibrium pulses, giving high signal from CSF at short TRs in spinal MR imaging. Methods and materials: High resolution 3D TSE Drive images of the spine are acquired with the following protocol (1.5 T): 24 to 48 slices, 1 to 2 mm thickness, TR 700 -1000 ms, and TE 80 -120 ms. The acquisition time is 4 to 6 minutes, depending upon the volume. Results: 3D TSE Drive images have a high Signal-to-Noise ratio, and a marked myelographic effect. The 3D acquisition reduces the CSF flow artifacts, and allows multiplanar reformattings. We seek to provide an all encompassing review of the 3D TSE Drive sequence and its place in spinal imaging protocols. We compare the Drive images and FSE T2 or STIR images. Presentation of selected cases illustrating its utility and limitations in degenerative, traumatic, infectious, or post-operative lesions of cervical, thoracic, and lumbar spine is provided. Conclusion: The 3D TSE Drive sequence is useful in the precise evaluation of degenerative disc disease, and syringomyelic cavities. Limitations include a low sensitivity to inflammatory lesions of bone marrow and spinal cord, due to complex contrast characteristics. 

Total spine examination with standard acquisition protocols requires a compromise between spatial resolution and examination duration. The total spine examination with MobiTrak consists of three stacks of 5 slices. For each stack a FOV of 300 mm, a slice thickness of 5 mm, and a reconstruction matrix of 512 are currently used. The table moves automatically, step by step. Scan times (1.5 T) are 3 minutes for SE T1-weighted, 4 minutes for TSE T2weighted, and 4.40 minutes for STIR sequences. Results: We seek to provide an all encompassing review of the MobiTrak technique and its place in spine imaging protocols. A discussion of the technique itself and presentation of selected cases (tuberculosis, spinal metastases, and myeloma) emphazising its utility in multifocal or diffuse involvement of the spine are provided.

The MobiTrak technique provides a rapid an efficient total spine examination. It is especially useful in the diagnosis and follow-up of infectious and tumoral multifocal lesions.

Pictorial review of diagnostic imaging techniques in detection and evaluation of acute and chronic osteomyelitis D.G.H. Devos, K.L.A. Verstraete, G. Vanderschueren; Gent/BE Purpose: To demonstrate the usefulness of plain radiography, computed tomography (CT) and magnetic resonance imaging (MRI) in the detection and evaluation of acute and chronic osteomyelitis (OM). To define the advantages and disadvantages of each technique.

We reviewed the imaging files of 50 patients sent to our department with a diagnosis of osteomyelitis. Plain radiographs, CT-and MR-examinations were evaluated by three radiologists. By consensus reading diagnostic criteria for confirmation of OM were forwarded separately for each technique. These diagnostic criteria will be illustrated accordingly. Results: Plain radiography is a non-expensive and easily accessible technique, but has low sensitivity and specificity; it may be able to detect sequestra, unless the surrounding bone is hyperostotic. CT is the modality of choice for the detection of sequestra. MRI is very accurate in detection and evaluation of abcesses, fistula formation, myositis, periostitis and Brodie-abces. The combination of T1-weighted with fat-suppressed T2-weighted images permits diagnosis in most cases. For evaluation of abscesses and fistulae, gadolinium contrast media may be useful. The presence of titanium osteosynthesis does not preclude the use of MRI. Plain radiography and MRI should be used in conjunction to differentiate diabetic foot from neurogenic osteoarthropathy. MRI is the imaging technique of choice for follow-up of chronic OM during therapy. Conclusion: Plain radiography and MRI both are the imaging modalities of choice in detection and evaluation of acute and chronic osteomyelitis. CT is indicated to find sequestra in chronic OM, especially in hyperostotic bone.

Imaging of hook of hamate bone fractures in conventional X-rays and CT: An experimental study and clinical experience R. Andresen 1 , S. Radmer 2 , J. Brossmann 3 ; 1 Güstrow/DE, 2 Berlin/DE, 3 Kiel/DE Purpose: Examination of the ability to image fractures of the body and hook of the hamate bone on conventional X-rays and HR-CT.

In an in vitro experiment on 18 cadaver hands, the hook of the hamate bone was fractured at different localizations. Before and after fracture, conventional X-rays were taken in different projectional planes: AP, lateral, oblique and carpal tunnel view, as well as an HR-CT with 2 mm slice thickness in the axial, sagittal and coronal planes. In addition, 15 clinically verified hook of hamate bone fractures were retrospectively reviewed to assess the value of the imaging procedures that led to diagnosis. Results: Using all of the conventional X-ray projections applied, the in vitro experiment revealed a sensitivity of 72.2 %, a specificity of 88.8 % and an accuracy of 80.5 %. For the CT, the sensitivity was 100 %, the specificity 94.4 % and the accuracy 97.2 %. In the retrospective clinical evaluation, 60 % of the existing fractures were identified in the conventional X-ray images. The remaining fractures were detected by additional procedures such as conventional tomography, scintigraphy and CT. Conclusion: Fractures of the hook of the hamate bone cannot always be detected with certainty in the conventional X-ray image, even if different projectional planes are used. HR-CT is the imaging procedure of choice for further clarification, where axial and sagittal plane imaging should be performed.

Vascular tumors of bone P. Martínez-Miravete, J.D. Aquerreta, F. Bergaz, E. Torres, D. Cano, E. De Alava; Pamplona/ES Purpose: Vascular tumors of bone are rare primary neoplasms representing less than 1 % of primary bone tumors. Our aim is to describe the radiologic appearances of these tumors and to present the pathologic correlation. Material and methods: We have reviewed the bone tumors files in our hospital. We found 75 hemangiomas, 3 hemangioendotheliomas, 12 hemangiopericytomas, 6 angiosarcomas and 1 angiomatosis case. Plain radiography, CT and MR features have been analysed. Results: Hemangiomas of bone are the most frequent tumors. They are benign lesions that comprised only 0.85 -1 % of all bone tumors. The two most common sites of involvement are the vertebrae (thoracic segment) and the skull. A vertical trabecular pattern is identified in the vertebral body. Angiomatosis is characterised by widespread cystic lesions of bone that frequently are combined with visceral involvement. Hemangioendothelioma is a rare tumor, comprising 0.5 % of all primary malignant tumors. Radiographically, the lesions are osteolytic, sometimes well delineated and sometimes permeative. The behaviour of Hemangiopericytoma originating in bone is unpredictable and only a few cases have been reported. Angiosarcoma, a rare malignant tumor of bone, is more frequent in men than in women, predominates in the long tubular bones and the principal radiographic pattern is one of osteolysis. Conclusion: Vascular tumors are uncommon bone tumors that should be kept in mind when bone lesions with a trabecular pattern are seen. When osteolytic lesion are detected, they are also one of the possibilities in the differential diagnosis. Methods and materials: The extensor and flexor tendon apparatus of one fresh and one formalinized cadaveric hand, as well as the ligaments, the distributing nerves and the bed of the nail were investigated using a 5 -12 MHz broad band linear transducer (HDI 5000, Advanced Technology Laboratories Bothell Washington) in longitudinal and transverse section planes. US findings were compared with corresponding cryo-sections using a fine needle band saw.

The flexor tendons and all anular pulleys (A1 -A5), the ceck rein ligaments, joint structures, aponeurosis of the extensor tendons, the digital nerve branches, and the bed of the nail were depicted using US. Conclusion: High resolution US allows detection of even very small structures of the finger and, therefore, can be a helpful tool to diagnose several types of finger injuries.

Primary Ewing's sarcoma of the vertebral column: Imaging characteristics H. Ilaslan, M. Sundaram, K.K. Unni, F.H. Sim; Rochester, MN/US Ewing's sarcoma constitutes approximately 10 to 15 percent of all bone sarcomas, is common in adolescence with a peak incidence in second decade of life and rare in black populations. It typically involves the pelvis and long bones. Primary involvement of vertebral column is uncommon. We performed retrospective review of images and medical records of patients diagnosed with Ewing's sarcoma in our institution from February 1938 through August 2001. There were 603 cases, 47 (8 %) of which primarily involved vertebral column. Males were affected twice as frequently as females; 32 males (68 %) and 15 (32 %) females. Ages ranged between 7 and 52 (mean 16.1). Distribution of cases was as follows: 26 (55 %) sacral cases, 14 (30 %) lumbar vertebra cases, 6 (13 %) thoracic vertebra cases and 1 (2 %)case of cervical vertebral involvement. In this exhibit we will present several examples of primary Ewing's sarcoma of vertebral column, as depicted on radiographs, CT and MRI.

The spectrum of cervical spine injuries in elderly patients: What is common and what is commonly missed? F. Lomoschitz 1, 2 , C.C. Blackmore 2 , K.F. Linnau 2 , S.K. Mirza 2 , F.A. Mann 2 ; 1 Vienna/AT, 2 Seattle, WA/US The clinical and imaging diagnosis of cervical spine injuries in the elderly is challenging. Elderly patients are known to be at increased risk of cervical spine injuries. A striking feature of older patients is their propensity to suffer major cervical spine injury from seemingly minor trauma. Age-related comorbidites, such as concurrent medical illness and dementia may distract from an accurate and reliable clinical evaluation. Spondylosis or osteoporosis distort vertebral anatomy and may render normal standard paradigms less useful in detecting injury, create structures outside the standard paradigms usually used in pattern recognition and may obscure radiographic signs of trauma. In fact, up to 15 % of all cervical spine fractures and up to 40 % of dens fractures may be missed on initial evaluation. The purpose of this exhibit is to improve knowledge of common injury patterns of the cervical spine in elderly patients. Familiarity with common pitfalls will facilitate recognition of clinically important injuries and shall help avoid misdiagnosis.

Magnesium-deficiency -a risk factor for osteoporosis B.M. Stoeckelhuber, C.U. Bergmann-Koester, H.D. Weiss, P.M. Rob; Lübeck/DE Purpose: We investigated the effect of magnesium (Mg) on bone mineral density (BMD) and bone fragility. Materials and methods: We induced dietary Mg-deficiency in rats for 52 weeks; 8 rats were fed a low Mg diet and 8 rats a normal Mg diet. Post mortem, BMD of the lumbar spine and femur was measured by dual energy X-ray absorptiometry (DEXA). Bone fragility of the femur was assessed by in vitro mechanical testing (linear elastic stress analysis). Results: Greater magnesium intake was significantly associated with greater BMD at the lumbar spine (0.308 g/cm 2 vs 0.251 g/cm 2 ) and femur (0.317 g/cm 2 vs 0.267 g/cm 2 ). The impact strength studies showed that a lower energy was required to fracture femurs of magnesium depleted animals (137 N vs 169 N). Conclusion: Magnesium deficiency is a cause of increased bone fragility and, therefore, a risk factor for osteoporosis. Ongoing studies will help to assess magnesium induced changes in bone metabolism. The aim of the study is to assess the value of computed tomography supplemented by three-dimensional reconstructions in the diagnostics of vertebral fissure and spondylolisthesis and in the qualification for operative treatment. Material and method: CT examination was performed in 17 patients with vertebral fissure and spondylolisthesis recognized on standard X-rays of the backbone. From digital computer data of axial sections multiple planar and three-dimensional reconstructions were secondarily performed. Results: In 9 patients CT revealed intraspinal displacements of nucleus pulp fragments coexisting with spondylolisthesis and osseogenous narrowings of the spinal canal and intervertebral foramena. Those patients were selected for internal stabilization with decompression of the nervous system and posterior spondylodesis. In 8 patients with 1 st and 2 nd degree spondylolisthesis, no features of discopathy were found. With a normal width of intervertebral foramena they were selected for bilateral postero-lateral spondylodesis. In 2 cases CT examination was performed after postero-lateral spondylodesis with bone grafts. In 1 case displacement of one graft downwards by one segment was observed. Conclusion: Computed tomography supplemented by planar and three-dimensional reconstructions enables the assessment of spondylolisthesis and with close cooperation between the radiologist and clinician, allows selection of patients for adequate therapeutic procedures. CT also enables postoperative assessment of bone grafts.

Spatial imaging of intervertebral foramens in 3D CT in the diagnostic evaluation of chronic radicular syndrome of the cervical spinal segment W. Krupski, J. Zlomaniec; Lublin/PL Purpose: The aim of the paper is to assess the value of CT spatial reconstruction (3D) of intervertebral foramena in the diagnosis of chronic cervical radicular syndromes.

Method and material: The study population comprised 22 patients aged 43 -68 years with chronic cervical radicular syndromes who either did not respond to conservative treatment or who presented with recurrent symptoms. They were subjected to a CT examination of the C4 -C7 spinal segment with secondary spatial reconstructions. Spatial reconstructions were placed in the axis of intervertebral foramens in projections from the outside and, after cutting along spinous processes from a part of the reconstructed picture of the vertebral column, from the side of the vertebral canal lumen. The width of intervertebral foramena was compared at different levels recognising a narrowing with diameter reduction in relation to other intervertebral foramina on the same side. Results: In all 22 cases different degree constrictions of intervertebral foramens were found, caused by the presence of postero-lateral osteophyte stratifications of the edges of the cervical vertebral bodies. In 6 cases they were accompanied by osteophyte stratifications within intervertebral joints. In 17 cases these changes were bilateral and involved intervertebral foramena at the same level. In 3 cases these changes were multi-level and in the remaining 2 cases single intervertebral foramen were narrowed. Narrowings of intervertebral fissures at the levels of constricted intervertebral foramens were found in 12 cases. Conclusion: Chronic and recurrent radicular syndromes require the assessment of the width of intervertebral foramens in 3D CT, especially from the perspective of surgical treatment. 

In 10 patients with multiple myeloma a contrast-enhanced dynamic MRI (d-MRI) of the lumbar spine was performed. For dynamic measurements a fast gradient-echo-sequence (turbo fast low angle shot 2D) with machinecontrolled gadolinium-DTPA application was used. The value of the highest signal increase (amplitude A) was calculated for each of the 50 vertebral bodies. At a mean time interval of 6.2 months after the initial d-MRI the subsequent development of vertebral fractures was assessed by conventional MRI. The amplitudes of the vertebral bodies that collapsed in the observation period were statistically compared with those of the vertebral bodies that did not collapse. Results: During follow-up newly or progressive fractures occured in 6 of 10 patients (7 of 50 vertebral bodies). In the d-MRI studies obtained prior to fracture occurrence the amplitude of vertebraes that collapsed (A: 33.4 ± 5.2) were significantly higher (p < 0.001) than those of vertebraes that did not collapse (A: 16.8 ± 7.1).

This study suggests that the amplitude of maximal signal increase in dynamic contrast-enhanced MRI is a potential relevant factor to predict the risk of vertebral fractures in patients with multiple myeloma.

Bone marrow oedema syndrome of the hip and gadolinium administration A.H. Karantanas 1 , H. Heracleous 2 , I. Mountanos 3 , E. Karaiskou 1 , P. Argiri 1 ; 1 Larissa/GR, 2 Nicosia/CY, 3 Kalamata/GR Purpose: To investigate the usefulness of iv administration of contrast in bone marrow oedema syndrome of the hip. Methods and materials: 50 patients (7 -63 a) were examined with MRI. 21 patients were examined with a 1.5 T MR scanner and 29 with a 1 T MR scanner. The indication for MRI was peristent pain and/or abnormal bone scan or radiographs. Comparison was made between two pulse sequences: (a) T2-w Turbo Spin Echo with fat suppression for the 1 T or Turbo-STIR for the 1.5 T scanner, and (b) T1-w Spin Echo with fat suppression after contrast administration. The qualitative analysis included: 0 = normal marrow, 1 = oedema less than 50 % of the marrow of the femoral head, 2 = oedema in 50 -100 % of the marrow of the femoral head, 3 = oedema extending to the intertrochanteric area. The final diagnosis was confirmed with imaging and clinical follow up in 6 months. Statistical analysis was performed with Mann Whiteney Rank Sum test. Results: The final diagnosis was osteonecrosis (18), transient osteoporosis of the hip (24), Perthe's (4), slipped capital epiphysis (2), migrating polyatrhropathy (1) and osteochondral injury (1). No correlation was found between the underlying pathology and the extension of the oedema in the femoral head. No difference was found between the subgroups examined by different MR scanners. The extension of the oedema in the marrow was identical with both sequences in either MR scanner (p = 0.592 for the 1 T and p = 0.550 for the 1.5 T).

Gadolinium-enhanced images add no information in the evaluation of the extension of bone marrow.

Chordoma: A pictorial review with radiological and pathological correlation W.K. Chooi, S. Nadkarni; Sheffield/GB Purpose: The aim of this pictorial review is to review and demonstrate the radiological and pathological features of chordoma. Introduction: Chordoma is a rare primary bone neoplasm arising from primitive notochordal elements. Although classified as malignant it is locally invasive and tends to spread along nerve sheaths and plexii. It is thought to occur slightly more commonly in males and in the 40 -60 age group. The diagnosis is based on the typical distribution of these tumours and a combination of radiological and pathological findings. Radiology: Chordomas occur in the midline reflecting their notochordal origin. The sacrum (50 %), spheno-occipital (30 %) and spine (20 %) are the three most common sites. The plain radiograph shows a destructive lytic lesion often with a soft tissue component and calcification. CT scanning is better at demonstrating the degree of bone destruction. MRI best displays the locally invasive nature of the tumour into the surrounding soft tissues including neural tissue. Radionuclide bone scanning and PET may have a role in follow up of treated cases. Pathology: Chordomas are soft, lobulated tumours with areas of haemorrhage and necrosis. They are typified by physaliferous cells, which have an abundant eosinophilic mucinous cytoplasm. Two histologic variants, chondroid chordoma and dedifferentiated chordoma have been described. Immunohistochemistry and cytogenetics are becoming the mainstay of pathologic diagnosis.

Bone mineral density in women with thyrotoxicosis I.S. Vlasova; Moscow/RU Purpose: To assess bone mineral density (BMD) in women with thyrotoxicosis. Material and methods: 57 females, with a history of thyrotoxicosis, were assessed with quantitative computed tomography and 38 patients with forearm dual X-ray absorptiometry. Results: Our results (Z-score) show a decrease in vertebral trabecular (22.82 %), ultra distal forearm (23.68 %) and distal forearm (31.58 %) BMD. TSH level were decreased in patients with reduced ultra distal forearm BMD (p < 0.05) and, particularly, FT4 serum levels had a negative relation to vertebral, ultra distal and distal forearm BMD (r = −0.30, p < 0.05 and r = −0.48, r = −0.43, p < 0.01, respectively), as well as positive correlation of ultra distal forearm BMD to TSH level (r = 0.40, p < 0.05). These findings demonstrate the negative influence of hyperthyroidism on both trabecular and cortical bone. A significant difference between patients with decreased and normal vertebral and ultra distal forearm BMD, depending on disease commencement age, was found (p < 0.05). This is confirmed by negative vertebral and forearm BMD correlation with hyperthyroidism debut (r = −0.39, p < 0.05). Osteopenia and osteoporosis (T-score) of trabecular vertebrae (65.79 %) and forearm (39.47 % and 44.74 %) are more prevalent among patients with hyperthyroidism. We observed significant difference between decreased and normal vertebral BMD, according to menopause duration and age. Besides, negative vertebral trabecular and ultra distal forearm BMD dependence on menopause duration (r = −0.66, r = −0.35, p < 0.05) and age, the highest in vertebral trabecular (r = −0.72, p < 0.001) and the lowest in distal forearm values (r = −0.41, p < 0.05), was found. Conclusions: Thyrotoxicosis negatively influences both types of bone tissue and is mostly related to hyperthyroidism decompensation. Calcium loss in predominantly trabecular bone is aggravated by postmenopausal and age-related changes. Results: The software developed for the assessment of bone mineral mass is aimed at performing the IP of of 1 mm thick axial section CT. A new parameter, namely bone density index equal to the ratio "bone area/no-bone area" was introduced for the effective description of bone density. The bone density index indirectly characterizes BMD. Comparison of results of IP of computed tomograms of LV preparations with the data of spectral analysis of their mineral composition revealed correlation (r = 0.75) between the bone density index and the amount of calcium and phosphorus in the investigated specimens. Since the amount of calcium and phosphorus which are the dominant elements of hydroxyapatite strongly affects BMD, the bone density index characterizes BMD satisfactorily. Conclusion: IP of computed tomograms is an effective method of BMD assessment. The method could be considered to be an alternative to other expensive diagnostic methods (CCT, HRCT and MRI).

Reduction and stabilization of tibial head fractures under fluoroscopic control -indications and possibilities R.V. Kastelov, C.G. Deliverski; Sofia/BG Purpose: The goal of this study is to introduce the radiologic findings of different types of tibial head fractures suitable for percutaneous reduction under fluoroscopic control and stabilization using minimally invasive surgery. Methods and materials: During the period of 4 years (1997 -2000) using fluoroscopy and minimally invasive surgical techniques we operated on 73 patients. They were devided according to J. Schatzker as follows: type I 16, type II 5, type III 3, type IV 21, type V 17 and type VI 11. There were 42 male and 31 female patients. The mean follow-up period was 2.5 years. Results: We achieved anatomical reduction with 31 (83.8 %) of type I and type IV fractures, with 3 (37.5 %) of type II and type III, and with 8 (47.1 %) of type V fractures. For type VI we achieved fair anatomical results with 6 fractures (54.5 %) and very good angulatory stability and functional results. Conclusion: Injuries appropriate for reduction and stabilization under fluoroscopic control are split fractures (type I and IV) of both condyles. For types II and III reduction of fragments is difficult and not so effective because of monoplane visualization of tibial head. For type V it is possible to drive and reduce only large medial fragment(s). For comminuted fractures associated with metaphyseal-diaphyseal dissociation (type VI) the closed techniques described above result in very important achievements -stability and early movement of the knee. Purpose: TBMES is a painful condition characterized on MR images by a diffuse edema of the subchondral bone marrow, which typically occurs in the hip joint; however unusual locations can be seen, such as the talus, the calcaneus, the navicular, the cuboïd, the femoral condyle or the proximal portion of the tibia. The objective of this exhibit is to describe the MRI findings in this disease. Materials and methods: 24 patients presenting with painful disability of hip (n = 9), knee (n = 7) or foot (n = 8), and normal radiographs, were explored by MRI. Clinical follow-up was performed during a 6 months to 1.5 year period. Results: The abnormality was characterized by decreased signal intensity on T1weighted images and increased intensity on T2-weighted and STIR images. A joint effusion or a soft tissue swelling was present in most cases (n = 20).There was complete remission of the clinical symptoms after 4 -11 months. Follow-up MR images obtained from 5 patients showed complete resolution of the lesion. Three patients had recurrence of the symptoms in another location. Conclusion: Since TBMES is often a diagnosis of exclusion, familiarity with unusual sites of the disease is useful in the differential diagnosis of patients with unexplained lower limb pain and normal radiographs. MRI is the most valuable tool in the assessment of this condition.

Value of FDG-PET investigation in patients with primary malignant bone tumors T. Györke 1 , T. Zajic 2 , S. Högerle 2 , I. Brink 2 , A. Joe 2 , E. Moser 2 ; 1 Budapest/HU, 2 Freiburg/DE Purpose: To evaluate the value of 18 F FDG-PET investigation in patients with primary malignant bone tumours in a retrospective study. Materials and methods: 32 patients (ages: 6 -73, 21 males, 11 females) with suspicious primary malignant bone tumours were included in the study evaluating PET investigations of five years period. The absorption corrected images of 38 FDG-PET investigations performed in the primary or secunder diagnostics were analysed visually and semiquantitatively with use of Standard Uptake Value (SUV) and Tumour to Background Ratio (TBR). The final diagnosis based on histology, imaging and follow up. Results: The sensitivity and specificity for disease (primary bone tumour, and/or its metastases) were 96 and 64 % respectively. Altogether 100 focal lesions were detected by PET and/or other imaging modalities. Sensitivity and specificity regarding focal lesions were 72 and 58 %. This low specificity is due to small lesions. In true positive cases SUV and TBR were 6.0 ± 5.9, 8.4 ± 10.4, in false positive cases 3.2 ± 0.7 and 4.6 ± 2.3, respectively. True and false positive cases could not been differentiated definitively based on SUV and TBR values because of overlap. Conclusion: FDG-PET investigation is a valuable method in case of primary bone malignancies. The determination of its role in diagnostic algorithm needs further investigations.

Imaging features of destructive spondyloarthropathy of the cervical spine in long-term hemodialyzed patients A. Leone 1 , M. Sundaram 2 , A. Costantini 1 , A. Cerase 3 , G. Guglielmi 4 , P. Marano 1 ; 1 Rome/IT, 2 St. Louis, MO/US, 3 Siena/IT, 4 San Giovanni Rotondo/IT As patients survive longer on hemodialysis (HD), cervical spine destructive spondyloarthropathy (DSA) has become increasingly recognized. The vertebral involvement can lead to medullary compression requiring surgical decompression and stabilization. Our primary objective is to describe the spectrum of vertebral changes from early erosions to the more aggressive resorptive changes, subluxation and listhesis by presenting the cases of some of the 31 HD patients included in a 6-year prospective study. The lower part of the cervical spine is predominantly involved, though the craniocervical junction may also be affected. In one patient, CT showed bone resorption due to a pseudotumor, basilar invagination and prominent prevertebral soft tissue. DSA may resemble spondylodiscitis. Even the MR imaging features are not pathognomonic, but if low signal in T2-weighted images is present, an infection can be excluded. In two patients we found an increased signal intensity on T2-weighted images and post-contrast enhancement from the affected disks and adjacent end plates. Differentiation from other metabolic discitis (gout and CPPD deposition) is discussed.

End plate lesions: Correlation with intervertebral disk degeneration on MR imaging I. Ioannidis, A. Haritanti, A. Lefkopoulos, N. Siskas, E. Xinou, D. Hardalidou, A.S. Dimitriadis; Thessaloniki/GR Purpose: To investigate with MR the correlation between end-plates lesions (EPL) and intervertebral disk degeneration. Materials and methods: We retrospectively reviewed sagittal T1-and T2-weighted MR images of 105 patients (525 lumbar disks) aged 22 -78 a (median 50 a), with chronic low back pain. MR images were evaluated for disk degeneration, height, contour and EPL, by two experienced radiologists. Grading of disk degeneration was based on the Pearce classification in 5 stages. Disk height was evaluated as a separate parameter as normal, slightly, moderately decreased and collapsed. Disk contour was evaluated as normal and abnormal (bulging or herniation). EPL were classified as normal, type I, II or III according to Modic classification. Interobserver agreement for EPL grading and disk degeneration was calculated. We correlated EPL with disk degeneration, height, contour and age. The statistical analysis was performed with univariate logistic regression and multivariate analysis. Results: Normal EPL were identified in 70.7 % and type I, II and III in 5.3 %, 19.5 % and 4.5 % of the intervertebral interspaces respectively. 84.8 % of EPL had grade IV -V disc degeneration and 83.3 % had abnormal contour. In univariate analysis, EPL were strongly correlated with grade IV -V disk degeneration (odds ratio 6.27, p < 0.001), collapsed disk (OR 13.78.p < 0.001), abnormal contour (OR 5.33, p < 0.001) and age (OR 1.55, p < 0.001, every 10-year increase). In multivariate analysis, only grade IV -V disk degeneration (odds ratio 3.62, p = 0.003) and collapsed disk (OR 6.73, p = 0.002) demonstrated a strong association with EPL. Plain films are not easy to perform and often unreliable in controlling the positioning of fixation devices. Using helical CT to detection misplaced fixation devices of the spine. Methods and materials: Post operative helical CT with a simple acquisition protocol adapted to the region of interest is the recommended procedure. It allows high image quality and multiplanar reconstructions. Metallic artifacts are considerably reduced due to current protocols as well as the recent use of titanium containing orthopedic material. Results: CT may detect various aberrant placements of screws: in a disk, outside the pedicle (inside or outside the spinal canal, with high risk of neurologic, vascular or digestive damage), as well as osseous fragments in the spinal canal. Conclusion: Helical CT is recommended in the detection of misplaced fixation devices of the spine.

In vivo biomechanical analysis of tensional deformability of human lumbar spine segments M. Kurutz, A. Lovas, P. Molnár, E. Monori, É. Bene; Budapest/HU Purpose: Tensile deformability of human lumbar spine segments has been determined during a wide-ranging in vivo biomechanical experimental analysis. The elongations of lumbar spine segments were measured during traction hydrotherapy. The influence of several biomechanical parameters such as age, sex, body weight etc. has also been analyzed. Methods: Tensile deformations of human lumbar segments LIII -IV, LIV -V, and LV -SI were measured. We have developed a special subaqual ultrasound measuring method. The elongation of lumbar segments were considered and measured as the change of the distance between the spinous processes of neighbouring vertebrae. More than 3000 ultrasound pictures of about 400 lumbar segments of 155 patients have been measured and evaluated. All of them were done on a multislice CT scanner (Mx8000; Marconi Medical Systems) with variable slice thickness (0.5 -2.5 mm) and reconstruction intervals (0.3 -1.3 mm) according to the anatomic region. Only one acquisition in the axial plane was carried out. Then, the images were transferred to a workstation (MxView; Marconi Medical Systems) where MPRs in the coronal, sagital or any other plane were created. Results: 36 fractures were diagnosed in the original images; the MPRs showed better the articular involvement, or the displacement of the bone fragments in 23 cases. In four cases the MPRs made the diagnosis of bone fractures (two transversal sternal fractures; one olecranon avulsion-fracture; one transversal scaphoid fracture). Conclusion: Isotropic MPRs are a useful and in some cases a necessary diagnostic tool to determine the presence or the real extension of a bone fracture.

Hand trauma with bone injuries from burst firecrackers: Radiological approach A. Nunziata 1 , A. Salzano 2 , L. Nunziata 1 , C. Caiazzo 1 ; 1 Naples/IT, 2 Frattamaggiore/IT Purpose: The hands are particularly involved in firecracker trauma, with bone injuries classified as burst fractures. Among radiological techniques, traditional X-ray investigation still remains an important approach in diagnosing the types of skeletal lesions. The aim is to illustrate the various kind of bone injuries and the indirect radiological signs regarding hand ligament and joint involvement by firecracker injuries and to evaluate the after effects of hand lesions. Materials and methods: We report a retrospective study on 167 patients studied from 1995 to 1999 (155 males and 12 females with mean age of 17 years, range 4 -74 years) hit by fireworks in the Naples area during the Christmas period. Radiographs were performed in 112 subjects and showed hand bone injuries in 96 cases. Results: Right hand involvement was seen more commonly (63 %) than left. Xray showed 43 metacarpal injuries, 41 amputations of terminal phalanges, 24 proximal phalange injuries; in 21 cases multiple injuries were present. Most of patients (83 %) were wounded at the beginning of New Year's Eve; other patients were not observed till the Witch Day, due to the harvest of unexploded firecrakers ("day after" injuries) after the 31 st of December. Follow-up hand radiographs after 2 years were performed in 90 subjects; showing osteoporosis in all cases and reduction of cortical bone in 67 cases.

The accurate radiographic evaluation of firecrackers trauma is necessary to give to the specialist a complete view of hand bone injury, and to suggest a suitable surgical or conservative strategy.

Comparison of cortical bone volume and cortical structure in CT images in relation to osteoporotic vertebral fracture M.A. Haidekker 1 , R. Andresen 2 ; 1 La Jolla, CA/US, 2 Güstrow/DE Purpose: To assess the value of cortical volume and cortical structure in CT images as a non-invasive predictor of vertebral fracture load. Materials and methods: 40 female patients with and without osteoporosis-related fractures were analyzed. HR-CT images were obtained from lumbar vertebrae L1 -L3. After segmentation of cortical and spongy bone, spongy and cortical bone mineral density (sBMD and cBMD) were determined separately. Cortical bone volume VC was determined. Quantitative parameters to describe cortical structure were obtained through the methods of low-BMD cluster counting (PC) and analyzing the gray-value profile of the cortical ridge (PR). All values were related to age and compared between the groups. Results: BMD and both structural parameters in the cortical shell were significantly correlated with age (sBMD: r = −0.84, cBMD: r = −0.66, PC: r = 0.46, PR: r = 0.56; p < 0.005 in all cases), while no significant correlation between cortical volume and age was found. BMD and cortical structure differ significantly between patients with and without fractures. Cortical volume is 8.5 % lower in patients with fractures, but but not statistically significant. Discussion: Cortical bone deteriorates slower than trabecular bone. With reduced spongy BMD, the cortical shell takes up an increasing part of the vertebral load. We found the hypothesis that cortical volume significantly changes with age and differs between osteoporotic and non-osteoporotic groups not to be true. Both BMD and structural parameters (which are independent from BMD and volume) significantly change with age and the number of fractures, thus allowing a prediction of fracture risk.

The pelvic ring is an anatomically stable structure due to a capsuloligamentous system. Rotational stability is provided by the anterior supporting structures (symphysis pubis, anterior sacroiliac, and sacrospinal ligaments) and vertical stability depends on the posterior tension band provided by the iliolumbar and posterior sacroiliac ligaments. Method: The ring concept dictates that a break in one location is associated to a break elsewhere in the same structure. Young classifies pelvic ring fractures into stable (A type), rotational instable (B type), and vertical instable (C type) groups. Results: Radiologic examination is initially based on plain radiography. CT scanning has become an essential element in the diagnosis and preoperative planning of pelvic, sacral, and acetabular fractures. Different studies have shown that up to one third of pelvic fractures detected by CT scan are missed on routine radiographs. In spite of this, the plain radiograph must not by replaced by CT as the first step in the diagnosis of pelvic ring injuries. Indications for CT scanning are acetabular fractures, dislocations of the hip, all potencial or recognized sacral or sacroiliac fractures and any question of stability in the pelvic fracture. Although patient status determines the need for angiography, certain types of injury predict the need for this, these include sciatic notch, sacrum fractures and vertical shear pattern. Conclusion: Plain radiography is the first study in a pelvic trauma and when instability is suspected, CT scan is definitive for a correct evaluation. To evaluate the outcome of intra-articular contrast agent injection in US examination of supraspinatus tendon traumatic-degenerative disease. Materials and methods: 20 patients (16 with impingement and/or suspected tears of the rotator cuff and 4 with anterior shoulder instability, acting as control group) were evaluated by means of US before and after intra-articular contrast agent injection (15 -20 ml of dimeglumine gadopentate, with 0.25 % saline solution). US examinations were performed with 10 -13 MHz linear arrays probes, just before patients underwent MR arthrography, considered as gold standard. Results: We divided the study population into four groups -A group: no tear or degenerative tendinopathy (4); B group: partial focal tear (10); C group: complete tear (2); D group: controls (4) -depending on the tendon echostructure and the presence of fluid into the subacromial/subdeltoid (SA/SD) bursa on conventional US scan. US Arthrograpy showed that 2/4 cases previously classified "no tear" by conventional US (A group), were actually partial focal tears (C group). Furthermore, 5/10 cases previously classified as "partial focal tear" by conventional US (B group), were actually complete tears 4/10 (C group) and 1/10 cases "degenerative tendinopathy" (A group). Finally, both of the the two B-classified cases were correctly diagnosed by US artrhography. In all cases MR arthrography confirmed the US arthrography findings (20/20). Conclusions: US arthrography of the shoulder allows a confident differentiation between complete and partial tear of supraspinatus tendon, by demonstrating the fluid passage from articular cavity into SA/SD bursa.

Post-traumatic pseudolipoma (fatty deformities): An unknown radiological entity N.H. Theumann, A. Abdelmoumene, M.-C. Gailloud, W. Raffoul, P. Schnyder; Lausanne/CH Purpose: To report the MRI features of this new radiological entity in nine patients who had undergone previous blunt trauma or local surgery. Materials and methods: Nine patients (mean age 36 years old, range 20 -48 years, sex ratio 8/1) presenting a total of 11 post-traumatic pseudolipomas were investigated. The etiology was blunt trauma in 8 patients and postoperative in one (bilateral lesions). The immediate underlying cause was always a haematoma. Clinically there were subcutaneous masses with the consistency of normal adipose tissue. The locations were upper thigh (n = 6), knee (n = 2), leg (n = 1), and ankle (n = 1). Eight patients underwent liposuction and one surgical excision. Pre and postoperative MRI were performed in all patients. Mean clinical follow-up was 28 months (range 11 -48) and showed no evidence of recurrence. MR imaging features were analyzed for fatty extension, bilaterality, distribution, contrast enhancement and presence of septae or soft tissue masses Results: The clinical masses included only fatty tissue. They appeared as asymmetrical fatty tissue in the injured areas compared to the opposite side. No margins could be demonstrated. No contrast enhancement, septae or soft tissue masses were noted. Conclusion: Post-traumatic pseudolipomas, or fatty deformities, should be recognised as a new radiological entity in patients who have previously undergone blunt trauma or surgical procedures which lead to deep soft tissue haematomas. 

Material and methods: 11 pts (10 males, 1 female) aged 406 years with frostbite (3 pts of both hands, 3 pts of both feet, 5 pts of both hand and feet) were scanned in 3 to 20 days from the onset of cold injury during winter 2000 -2001 using 370 MBq of 99 Tc-MDP. Results: 9 pts with 4 th degree frostbite had "cold" areas both in bones and soft tissues for an equal distance. 2 pts with 3 rd degree frostbite revealed "cold" area in the soft tissue and preserved visualization of bones. Five pts of 11 underwent scintigraphy 3 days after frostbite and revealed LD was verified by clinical and morphologic follow-up. DL was revealed scintigraphically in the projection of distal interphalangeal joints of hands and feet (n = 5), of middle third of feet (n = 4), of radiocarpal joints (n = 1) and of mean third of crus (n = 1). Conclusion: 2-phase scintigraphy is a safe method for early prediction of bone and soft tissue necrosis degree and allows optimal treatment of deep frostbite.

Electric burns: The role of MRI in therapeutic decisions E. Menif, H. Ben Romdhane, A. Baccar, K. Chelaifa, A. Messaadi, R. Slim; Tunis/TN Purpose: Electric burns cause important injuries of the soft tissues which treatment can lead to amputation. Nevertheless, the area of resultant injury and its gravity is often underestimated clinically with consequences for excessive amputations. The purpose of this work is to estimate the contribution of MRI to therapeutic changes. Material and methods: We studied prospectively five consecutive patients affected by electrical burns. Clinical exam found an evolving necrosis in the soft tissues of the upper limb in two patients, in two lower limbs in three patients and in the trunk of one patient. They had an MRI of the affected zones and neighboring regions which included T1W, T2W and post contrast sequences. Results: MRI showed extension of injuries beyond the limits apparent clinically. It allowed a distinction to be made between necrosed lesions requiring excision and inflammatory lesions which permit conservative treatment. Conclusion: MRI is a reliable and indispensable modality in the assessment of electrical burns. It is the only exam which allows estimation of injury extent with more precision than clinical examination, so allowing adjustments in treatment to be made.

Magnetic resonance imaging of tunnel syndromes I. Boric, M. Pecina, H. Pecina, D. Anticevic; Zagreb/HR Purpose: To evaluate patients with clinical symptoms of tunnel syndromes which may be caused by extrinsic or intrinsic pressure on the peripheral nerve or its branches. The specific symptoms depend on the extent of nerve involement and places of compression. Methods and materials: Seven patients were imaged using a 2 T MR system and four different cases of tunnel syndrome were present:

1. The supracondylar process, an atavistic bony formation can exist and be connected to the median epicondyle by a fibrous band (Struther's ligament). The median nerve was compressed in the fibro-osseous tunnel with Struther's ligament, creating symptoms of the supracondylar tunnel syndrome. 2. Carpal tunnel syndrome. The median nerve was compressed on his course through a fibro-osseous carpal tunnel by the flexor retinaculum. 3. The sciatic nerve passes through the greater sciatic foramen in close proximity to the piriformis muscle and can even run through it in several variations. Compression of the nerve passing through two heads of a divided piriformis muscle produced the clinical picture of the piriformis muscle syndrome. 4. The common peroneal nerve runs in an exposed fibro-osseous tunnel at the level of the fibular neck. Compression by ganglion cyst produces a characteristic clinical picture of peroneal tunnel syndrome. All MR findings were confirmed surgically. Conclusion: MR imaging helps in understanding the complex anatomic relationships and in making the nerve visible. The method is reliable for detecting causes of nerve compression. 

MRI examination of the lower extremities were analyzed in 70 patients with Gaucher disease type I. Additionally, the thoracic spine, the abdomen and the midface were investigated by MRI in two patients. Results: Four cases (6 %) are presented in which patients with Gaucher disease type I and severe skeletal involvement developed destruction or protrusion of the cortex with extraosseous extension into soft tissues. In one patient, Gaucher cell deposits destroyed the lateral cortex of the mandible and extended into the masseter muscle. In the second patient, multiple paraverebral and pelvic masses with localized destruction of the cortex were apparent. In the third and fourth patient, cortical destruction with extraosseous tissue extending into the soft tissues was seen in the lower limbs. Conclusion: Extraosseous extension is a rare manifestation of Gaucher bone disease. While an increased risk of cancer, especially hematopoietic in origin, is known in Gaucher patients, these extraosseous benign manifestations that may mimic malignant processes should be considered in the differential diagnosis of extraosseous extension into soft tissues. A narrow neck of tissue was apparent in all cases connecting bone and extraosseous extensions.

Purpose: To describe the imaging features in athletes affected by hamstring syndrome, a painful condition due to compression of sciatic nerve at the ischial tuberosity level. Materials and methods: 9 athletes (8 males, 1 female) suffering from pain felt over the ischial tuberosity area and radiating down in the back of the thigh underwent MRI after ultrasound preliminary evaluation. MR examination was performed using a 1.5 T unit (GE Horizon Medical System). Proton density, T1 weighted and T2 weighted sequences on axial and coronal planes were employed. In one case MRI was also obtained after surgical treatment. Results: In all cases MRI demonstrated pathological findings involving the ischial tuberosity region. They consisted in insertional pathology of hamstring tendons, inflammation disease of regional bursae and fibrotic changes of fatty tissue surrounding the ischial tuberosity. Conclusion: Hamstring syndrome is a painful condition often affecting athletes. MRI provides a correct evaluation of the ischial tuberosity region enabling an adequate therapy.

Morton's neuroma of the forefoot: Diagnostic imaging evaluation A. Catalucci, F. Iannessi, G. Cerone, M. Sabatini, M. Caulo, A.V. Giordano, A. Barile, C. Masciocchi; L'Aquila/IT Purpose: Morton's neuroma is a metatarsal condition due to compression neuropathy induced by an alterated biomechanical overload of the foot. Our aim is to evaluate the diagnostic capabilities of MRI in detecting and characterizing this pathologic condition. Materials and methods: 51 patients complaining about metatarsalgia were examined using dedicated 0.2 T and whole-body 1.5 T MRI units. All the patients previously underwent plain films. In forty-one patients an ultrasound (US) examination was performed. Nineteen patients also underwent computed tomography (CT). Results: In 26 patients both dedicated and whole-body MRI examinations revealed Morton's neuromas always confirmed by surgery. In nineteen patients MRI showed the presence of flexor digitorum longus tenosynovitis. In four cases MRI showed an interdigital bursitis and in two patients a stress fracture of metatarsal bone. Conclusion: On the basis of our experience MRI is the most accurate technique for the evaluation of Morton's neuroma and to detect and differentiating the various pathological conditions causing metatarsalgia.

Image fusion with MRI and FDG-PET: A new modality in evaluation of bone and soft tissue sarcoma B. Højlund Bech, K.E. Jensen, M. Nowak, H. Hendel, A. Eigtved, C. Thomsen; Copenhagen/DK Image fusion between MRI and FDG-PET in patients with bone and soft tissue sarcoma is presented. FDG-PET is a sensitive method for visualizing functional changes, but lacks the capability for precise anatomical localisation of these. Conversely, MRI provides information of the precise anatomical localisation of the tumor, but has difficulties in differentiating between tumor tissue and inflammatory changes. Therefore, co-registration could be of value, with a view to obtaining the best of both methods. Method/materials: Seven patients with bone or soft tissue sarcoma were included. MRI and FDG-PET scanning were performed with the extremity fixed in a mould to ensure identical anatomy without deformation of the surface. A surface-based algorithm was used for co-registering the PET transmission scans to the MRI data. The attenuation corrected emission scan was subsequently projected on the MRI scan. Results/conclusion: Co-registration was sensitive to tissue deformation and a well fitting mould used both for MRI and PET was essential. Volume scanning with identical parameters as slice thickness, slice position and angulation are crucial. We succeeded in co-registration of 7 patients. Two tumors expressed homogenous activity in PET and homogenous signal intensity on MRI including a post-contrast study. The other five tumors showed heterogeneity in both modalities. In four of these, MRI indicated a larger degree of tissue involvement than suggested by PET. These differences could not be detected without image fusion. Agreement was found between the histologic grade of malignancy and the degree of FDG uptake. These differences could not be detected without image fusion. Purpose: Hoffa's infrapatellar fat pad is a routinely visualized intracapsular structure on MR knee studies. A review of the wide pathologic entities seen in this region and the evaluation of the MR findings allow the differential diagnosis to be considered. Material and methods: MR knee studies in the last 7 years were examined. The studies were performed in a 1.5 T MR (GE System) using T1-SE, T2* FSE, fat suppressed T2 FSE and 3D SPGR sequences. Several patients underwent T1 gadolinium enhanced SE sequences. Results: Hoffa's fat abnormalities are classified in: (1) Intrinsic: (Hoffa disease, intracapsular chondroma, localized nodular synovitis, postarthroscopy and postsurgery fibrosis and anterior cruciate ligament injuries); (2) Extrinsic: (2A) Articular disorders (joint effussion, intraarticular bodies, ganglion cyst and cyclops fibrosis); (2B) Synovial anomalies (pigmented villonodular synovitis, haemophilia, synovial hemangioma, primary synovial chondromatosis, chondrosarcoma, lipoma arborescens, rheumatoid, seronegative and septic arthritis and osteoartrhitis); (2C) Extracapsular abnormalities (patellar fracture, patellar tendon rupture, Sinding Larsen Johansson disease, deep infrapatellar bursitis and Osgood Schlatter disease. Discussion and conclusion: MR information is crucial in the proper diagnosis of the Hoffa's fat pathology.

Value of MRI in the evaluation of pre-operative chemotherapy. Retrospective study in 33 soft tissue sarcomas M. Albiter, D. Vanel, A. Le Cesne, P. Terrier, S. Bonvalot, C. Le Pechoux; Villejuif/FR Purpose: Study the value of MRI in the evaluation of the response to neo-adjuvant chemotherapy. Materials and methods: Retrospective study of 33 patients treated for high grade soft tissue sarcomas between January 1996 and November 1999. Pre-treatment and after 2 cycles of chemotherapy imaging was obtained. In majority of patients it was a MR imaging, on a 1.5 T machine with T2 fat sat, T1 and T1 fat sat after enhancement sequences. In 3 patients pre-treatment evaluation was made by CT. MR imaging criteria used to quantify the response were: tumor volume (in each case) and tumor necrosis (evaluated after injection in 21 cases). All patients underwent a surgical resection within one month after completion of chemotherapy with histological taken.

The size of only one tumor increased, due to infection, remained unchanged in 21 cases (4 good, 8 moderate and 9 bad responders) and decreased in 11 cases (3 good, 4 moderate and 4 bad responders). The two tumors that decreased of more than 50 % were good responders. Necrosis increased in 11 cases (4 good and 7 moderate responders) and was stable in 10 cases (1 good, 4 moderate and 5 bad responders). Conclusion: Reduction of more than 50 % in size or increase of necrosis are good indicators of effective chemotherapy. Purpose: Hemangiomas are common congenital lesions. Interventional radiology, and surgical therapy may offer significant palliation and possible cures. It is crucial to choose the adequate method of therapy. Our purpose was to show how magnetic resonance (MR) techniques can help to determine the therapeutic approach. Method and materials: We describe findings in 11 patients (5 female, 6 male, mean age 16 a) with peripheral soft-tissue hemangiomas to illustrate the ability of MR imaging to define clearly and noninvasively the extent and anatomic relationships of hemangiomas, including identification of the vessel feeding a portion of the tumor. We performed T1 weighted and STIR sequences as well as MR angiographic sequences (arterious, venous, late phase). Results: The major advantage of MR imaging is the superb delineation between hemangiomas and the surrounding structures on MR images. Hemangiomas with a distinct border or a tumor like pattern indicate a surgical procedure. A further important tool is the use of MR-angiographic sequences in 3 phases. Feeding or Musculoskeletal draining vessels were visible in 2 cases. However the difference between the extent of the lesion in the arterial and the venous phase gave important information for therapeutic interventional procedures. Conclusion: The information obtained with MR imaging may be valuable clinically in planning surgical resection or in evaluating effectiveness of medical or interventional embolic therapy.

The role of ultrasound in evaluation the changes of acute soft tissue musculosceletal infection I. Krolo, M. Marotti, R. Klaric-Custovic, N. Babic, J. Hat, M. Doko, M. Doko; Zagreb/HR Purpose: To determine ultrasound capability for evaluating and staging the changes in patients with acute soft tissue musculosceletal infection. Methods and materials: During a period of two years ultrasound (7.5 MHz probe) was performed in 26 patients with acute musculosceletal soft tissue infection. 26 patients were examined (18 males, 8 females), aged 12 to 68 years. Localization of the changes was lower extremity 12, abdominal wall 8, gluteus 2, upper extremity 2 and thoracic wall 2. All patients had positive clinical, laboratory and local findings. Causes of acute infection were bacterial, viral or fungal agents (trauma 6, postoperatively 12, infection complicating and imunocompromised patients 8). We have evaluated inflammatory area with longitudinal and transversal scan, color and power Doppler. Cutis, subcutaneous, muscle and fascia thickening, diffuse swelling, edema, fluid collection, mixed echogenic areas, abscess and vascular changes were evaluated. Results: Subcutaneous edema was detected in all cases, mixed echogenic areas within thickened muscle (18), fascia thickening (16), fluid collection (12), abscess (2), joint involvement (2), increased number of enlarged blood vessels and decreased arterial resistance (10), changes in deeper soft tissues (2). In 1 case US guided fine needle aspiration was performed. Conclusion: Ultrasound is a simple, valuable method in the detection of soft tissue musculosceletal infection, useful in treatment planning.

High resolution sonographic standardized documentation of the carpal tunnel H. Czembirek 1 , O.J. Sommer 2 , H. Gruber 2 , P. Kovacs 2 , R. Steinbach 1 , M. Rieger 2 , M. Stiskal 1 ; 1 Vienna/AT, 2 Innsbruck/AT Purpose: The aim of a standardized documentation protocol of the carpal tunnel is: (1) to allow a second look (training purposes, therapeutic strategies), (2) to minimise the amount of redundant investigations, (3) to have a reliable document in forensic cases. Materials and methods: The sonographic standardized documentation protocol was performed in correlation with anatomic sections, multi slice CT and MRI imaging with multiplanar reconstruction. Anatomic landmarks where defined and the axial and longitudinal sections determined. Results: Using high resolution sonography considering the anatomic landmarks (radial artery, ulnar artery, os pisiforme, retinaculum and so forth), a standardized examination and documentation of the carpal tunnel is feasible. Conclusion: The implementation of standardized documentation of the carpal tunnel is expected to improve comparability and reproducibility of the quantitative analysis of the median nerve. It is a reliable method to detect and define pathologic situations in the carpal tunnel.

Imaging evaluation of fat distribution in treated HIV-1 infected patients E. Dion, M.-A. Valantin, P.-O. Gleyze, C. Katlama, P.A. Grenier; Paris/FR Purpose: Amongst the side effects related to therapy for HIV-1, lipodystrophy represents a major source of patient concern. The aim of this study is to assess fat redistribution in this population using CT. Methods and materials: We developed surface and volume calculations to assess fat distribution int the abdomen (intra and sub cutaneous fat), in the "Boules de Bichat", in the neck and in the thighs. Seven therapeutic arms were analyzed in three different studies (each study includes over 100 patients). At least two of these anatomical sites were evaluated in each patient both in terms of reproducibility, evolution over time and safety of the procedure. Results: High reproducibility of the fat volume can be obtained by volume rendering using helical CT. Central adiposity and peripheral wasting are the most common findings detected in patients treated with protease-inhibitor therapy. Conclusion: Assement of the fat volume by imaging can provide an accurate evaluation of the fat redistribution.

Elastofibroma dorsi: Evaluation by MRI S. Ortori 1 , V. Zampa 1 , F. Donati 1 , D. Carafoli 1 , E. Ceretti 2 , M. Cosottini 1 , D. Trippi 1 , P. Bagnolesi 1 , C. Bartolozzi 1 ; 1 Pisa/IT, 2 Forte dei Marmi/IT Objective: To determine if the MRI features of Elastofibroma are sufficient for diagnosis of this neoplasm. Materials and methods: Ten patients (6 female, 4 male; middle age 40) with a painless back mass underwent MR studies (0.5 T -1.5 T). The MR protocol included: SE TW, FSE T2, FSE-IR. Post contrast T1W SE images were available in 5 patients. Two radiologists read all images and the gold standard was surgery in 8/10 cases and follow up MR studies in 2/10 cases. Results: In each patient, semilunar soft-tissue mass (in 2 cases the masses were bilateral) isointense to the muscle was identified in the periscapular region deep to the postero-lateral muscolature of the chest. The isointensity corresponded histologically to fibroelastic tissue. Focal linear areas of hyperintensity reflected areas of fat within the tumor were also present. The gold standard provided 12 elastofibromas. Post contrast T1W images showed marked enhancement of the mass. However, also in these 5 cases, the unenhaced images were rapresentative in elastofibroma. Conclusion: A periscapular soft-tissue neoplasm demonstrating a pattern of linear alternating regions of high and intermediate signal intensity on T1 and T2W should be sufficient to allow the diagnosis of elastofibroma dorsi.

Evaluation of heterotopic ossification by MRI -first experiences A. Gisevius, A.-F. Foerster, R. Meindl, V. Nicolas, M.G. Henschel; Bochum/DE After spinal cord injury followed by plegia, heterotopic ossification (HO) around hips represents a frequent complication leading to severe restriction in joint motion or ankylosis. Developing mature forms of HO in soft tissue can be prevented by radiation treatment, if diagnosis is made early on. We report first experiences of using MRI for early detection of HO in comparison to other diagnostic imaging. Since 1998 64 patients suffering from tetra-or paraplegia after spinal cord trauma were examined for HO with MRI as well as some different imaging methods. In 23 cases there was no significant pathological result of MRI or other diagnostic imaging. MRI finding was false positive in two cases. All other patients showed edema and inhomogeneity of MRI signal in muscles and soft tissue, that later on mostly was proved as early forms of HO on ultrasonography, CT or 3-phase-bone-scan. In 10 cases CT already detected manifest ossifications, in 9 patients MRI was positive, before there were significant findings on ultrasonography. False negative results did not occur. According to our experiences MRI can be seen as a reasonable, well standardizeable and sensitive diagnostic method for detecting early HOforms. Advantages are anatomical correct visualisation, less limitations and absence of X-rays.

MRI in the assessment of recurrent liposarcoma B. Petrovic; Sremska Kamenica/YU Purpose: To assess MRI characteristics and patterns of the recurrence of liposarcomas, with regard to the contribution of gadolinium application, signal characteristics and false-positive and false-negative findings. Methods and materials: 38 MRI examinations of 24 patients, performed on a 1.5 T MRI system were included. All patients underwent at least one resection of a liposarcoma, and were examined 1 -42 months after surgery. Patterns of recurrence were determined on the basis of the standard MRI protocol, including fatsaturation techniques and gadolinium application. Results: The most common histologic types were myxoid and well-differentiated liposarcomas (83 %). In 3 cases (8 %) MRI was equivocal and a follow-up was required. In 2 cases (5 %) MRI was false-positive for a recurrence, both with the myxoid histology type. T1 hypersignal of fat was present only in cases of the welldifferentiated histologic types. A multilocular pattern of recurrence was present in 2 cases (5 %). Contrast enhanced studies added no diagnostically significant information, except in the equivocal cases (8 %). Conclusion: MRI is mandatory for the adequate reoperation planning in all cases of suspected local recurrence. Gadolinium application is unnecessary in the vast majority of cases, which is of considerable economic importance. All examinations should be monitored and tailored individually. Only few equivocal MRI findings require a follow-up examination.

Purpose: Angio MR (AMR) is rarely indicated for the fingers. We propose a technical procedure for AMR of the fingers and experience of this modality in 16 patients. Materials and methods: 16 patients with a suspected vascular lesion of the fingers (12 glomus tumors of which 5 had been operated on, 4 vascular malformations) underwent an MRI examination. All imaging was performed with a 1.5 T unit and a wrist coil. A prior acquisition of a subtraction mask and a dose test to determine the arterial time were first acquired. The standard 3D Fast-SPGR sequence was used with an elliptic centric acquisition (acquisition time 50 s). Contrast media was administered at 1 ml/s using a power injector. Full-slab MIP angiograms and thinner ones were compared with standard MR slices. Results: Arterial MR anatomy of the fingers was satisfactory in all patients with a good visualization of the periungual anastomoses. All primitive glomus tumors were detected on standard MR images as well as on MR angiograms. In 3 cases the glomus tumors appeared with ill-defined limits or complex enhancement. Standard MR images were poorly informative in the postoperative state due to scar tissue. MR angiograms were more useful with a specific early enhancement of the tumors. The lack of recurrence could be asserted with the negative MR angiograms. MR angiograms better showed the vascular nidus and the feeding vessels in hemangiomas. Conclusion: AMR of the fingers requires specific technical modalities and may be helpful to image recurrent glomus tumors and vascular malformations of the fingers.

Principles of multi-detector CT scan in the evaluation of musculo-skeletal disorders A.G. Blum; Nancy/FR Multi-detector CT scan (MDCT) provides significant improvements in the exploration of musculo-skeletal disorders: (1) Spatial resolution is improved in all directions, specially with 0.5 mm thick slices thus, the explored volume is nearly isotropic; therefore, a single acquisition in a pure axial plane providing high quality MPR is sufficient. (2) In soft tissues analysis, the signal-to-noise ratio is improved by increasing slice thickness directly from raw data calculation (native slices) or secondary with MPR. (3) Large volumes can be studied without sacrificing image quality. (4) Improved acquisition speed and temporal resolution yield a better preoperative vascular mapping of soft tissues tumours and a precise depiction of thoracic outlet syndrome. (5) 3D representations, specially VRT and MPVR, are more efficient to highlight subtle fractures and to outline vascular mapping. (6) Radiation dose can be reduced without significantly altering image quality. Learning objectives: (1) Illustrate and discuss through significant examples the different characteristics of Multidetector CT in musculo-skeletal disorders.

(2) Explain how to optimise image quality in the different anatomical regions.

High-resolution sonography of small parts: Evaluation of real-time compound imaging J.-Y. Meuwly, P. Rossier, P. Schnyder, A. Denys; Lausanne/CH Purpose: Real-time spatial compound imaging (sono CT) is a new ultrasound scanning technique which averages in one image the information provided by multiple angles of view. Real-time compound imaging has the potential to improve image quality compared to conventional ultrasound, because of a better definition of anatomical structures and a reduction of speckle, clutter, and other acoustic artifacts. The aim of this study was to objectivize the impact of real-time spatial compound imaging on small parts image quality in comparison with conventional ultrasound. Material and methods: Comparative high-resolution sonography was performed in 20 patients explored for a testicular, thyroid or breast abnormalities. Consecutive paired images were obtained by each patient with an ATL HDI 5000 scanner, using a high frequency linear probe. The images were independently evaluated by 3 radiologists (JYM, PR, AD) and rated using a 4 point scale. On each image, the items observed were the borders definition, the conspicuity of artifacts, the visibility of speckle and the global quality. Results: There was a large agreement between the four observers for all the items in conventional imaging (P < 0.001) and for the assessment of borders definition and global quality in compound imaging (P < 0.001). A good agreement was observed for the assessment of artifacts conspicuity (P < 0.02). No statistically significant agreement was found for the assessment of speckle visibility in compound mode (P < 0.1). A significant difference was observed for all items between conventional and compound imaging. Conclusion: Real-time spatial compound imaging of small parts improve image quality compared to conventional ultrasound.

The association between cervical ribs and sacralizations B. Gulek, E. Erken, H. Ozer, B. Durgun; Adana/TR Purpose: Our purpose was to investigate any statistical associations between cervical ribs and sacralizations, which we had radiologically and clinically observed before. Methods and materials: A cervical rib is an elongated transverse process of the seventh cervical vertebra, either with an articulation or not; but there is no consensus about the normal length of the transverse process. Anteroposterior cervical radiographs of 210 normal individuals (112 males, 98 females, mean age 33.9 ± 10.1), were taken for obtaining reference values. Elongations of tranverse processes beyond 2 standard deviations (30 mm), were considered as cervical ribs. Using these reference values as a guide, 324 outpatients (165 males, 159 females, mean age 42.0 ± 14.6), having cervical ribs and or sacralizations detected by AP-plain radiographs, were taken as the study group. Also, 729 volunteers (364 males, 365 females, mean age 41.7 ± 14.3), were taken to make the control group. Results: A total number of 1053 patients were examined. Of the 471 patients having cervical ribs, 345 (73.2 %) also had sacralizations. Of the 536 patients having sacralizations, 345 (64.4 %) also had cervical ribs. Significant associations were found between cervical ribs and sacralizations (X2: 170.269, p < 0.001); between cervical ribs with articulations, and sacralizations (X2: 52.284, p < 0.001); and between cervical ribs without articulations, and sacralizations (X2: 139.473, p < 0.001).

The presence of cervical ribs might be a clue to the existence of sacralizations, and vice versa. Knowing this association can be helpful in the differential diagnoses and follow-ups of patients with cervical or lumbar pains, before applying sophisticated diagnostic techniques.

Plantar foot pain: Differential diagnosis E. Santos Martín, S. Merino Menéndez, M. Jorquera Moya, M. Yus Fuertes; Madrid/ES Purpose: To illustrate the gamut of plantar foot pain on imaging (conventional radiography, CT and MR) Methods and materials: We reviewed current clinical cases and teaching files in patients with foot lesions and selected those in which plantar pain was the main symptom. Results: We will be presenting a multitude of plantar pain causative lesions and their imaging characteristics as well as the imaging modality needed to confirm its presence and to define its exact extent and best possible intervention. The causes of plantar pain are extensive and include: bone lesions (fractures, contusions, stress lesions, tumors, aseptic necrosis, infection), plantar fascia affections (fasciitis, tear, fibromatosis), soft tissue masses (neuroma, hemangioma, fibromatous angioma …)and infections, arthropaties (rheumatoid disease, gout, osteoarthritis, pigmented villonodular sinovitis …), bursitis and structural or mechanical pathology. In most cases, MRI was found to be more sensitive for the characterization of this pathology. Conclusions: Foot lesions are well depicted by imaging techniques and many times MR and CT provide specific findings and reliable distinguishing features among lesions. This poster is directed towards radiologists in training and will give a detailed outline of lesions and their appearances on different imaging techniques. Polytrauma often involves pelvic damage and can cause shock due to resultant massive bleeding. The diagnosis of the bleeding source represents a key radiological problem. Understanding the nature of the vessel damage is important for the surgeon and influences nature of further treatment. Purpose: To study the use of SCTA (Spiral computer-tomographic angiography) in the evaluation of vessel state in patients with pelvic injuries.

The research was carried out on a spiral computer tomograph "Somatom Plus 4A" (slice 3 -5 mm, increment 1.5, and start delay 35 -40 s, with two-and three-dimensional reconstructions). 10 patients (8 men and 2 women, age range 15 -47 years) were investigated. Presentations included; 4 fire wounds, 1 knife wound, 2 catatraumas, and 3 transport traumas. In 8 cases patients were haemodynamically unstable. Results: In all cases there was an increase volume of pelvic soft tissues with contour changes. The injured vessels were revealed in 2 patients by the presence of contrast extravasation and through the deformation and compression of vessels by hematoma and increased soft tissue in 3 cases. Intimate application of a foreign body to a vessel was observed in 1 case. Injury of vessels were not evident in the remaining SKTA studies. Conclusion: SKTA is an informative radiological method in the diagnosis of vessel condition in patients with heavy combined pelvic trauma.

Extended field-of-view sonography in musculoskeletal disorders. Usefulness in clinical practice G. Blanco-Eguren, M. Ruíz-Díaz, J. Martos-Fornieles, G. Álvarez-Bustos, G. Sanabria-Medina, A. Salvá-Veyn; Málaga/ES Aim: The aim of this study was to describe a new ultrasound technique, ultrasonography with extended field of view (USEFOV) and its clinical application in the evaluation of musculoskeletal diseases. Material and methods: We used a device from Siemens Medical Systems (SieScape; Iselin, NJ) equipped with a Multidimensional Crescendo image processor using a linear array of 7.5 and 13 MHz (Siemens Medical Systems), analysing its benefits in the diagnosis by images of musculoskeletal diseases. Results: USEFOV is beneficial in the evaluation, measurement, and diagnosis of large dimension images, showing the anatomical context and its relationship with the various surrounding entities. We describe and show different inflammatory and infectious tumour processes involving tendons, muscles and soft tissues. Conclusions: One of the most important limitations of US is its low FOV compared to other diagnostic techniques, such as CT or MRI. This new method for producing longer images has been developed with the idea of resolving this limitation. USEFOV provides a real-time panoramic analysis, using continuous ultrasound images obtained with a standard array and without the requirement of a position sensor. This technique affords a view of the topographic anatomy generating high quality images by combining the advances and advantages of static ultrasound in real time.

Rheumatology in the history of Spanish art. Radiological correlation G. Blanco-Eguren 1 , A. Bernal-Ruíz 2 , M. Ruíz-Díaz 1 , T. García De La Oliva 1 , G. Blanco-Rodríguez 3 , A. Salvá-Veyn 1 ; 1 Málaga/ES, 2 Andújar/ES, 3 Córdoba/ES Aim: To describe the pathological features concerning rheumatological diseases in artistic representations in the history of Spanish art, and analyse their correlation with radiographs of the various clinical entities.

Purpose: To describe the technical execution and the properties of 3D-US in the evaluation of normal anatomy of tendons and ligaments, using a computer-based interactive presentation. Materials and methods: Ten normal subjects with no history of joint trauma or pain were selected: in all subjects we examined both elbows, hands and ankles. An ATL HDI 5000 equipped with a broadband 7 -14 MHz transducer and 3D reconstruction software was used. Results: A pictorial review of the new anatomical features provided by this technique was achieved. Conclusions: 3D-US offers new possibilities in evaluating the complex course of the lateral collateral ligament of the ankle and in the study of the Achilles tendon and flexor tendons of the hand. The versatile features of the PC presentation appear optimal to show and describe our results in an interactive way.

Joints C-0577 Ligamentous and tendinous anatomy of the intermetacarpal and common carpometacarpal joints: MR imaging and MR arthrography N.H. Theumann 1 , C.W.A. Pfirrmann 2 , D. Resnick 3 ; 1 Lausanne/CH, 2 Zürich/CH, 3 San Diego, CA/US Objective: To demonstrate the normal ligamentous and tendinous anatomy of the intermetacarpal (IMC) and common carpometacarpal (CCMC) joints with MR imaging and MR arthrography. Material and methods: MR images of 22 wrists derived from fresh human cadaveric were obtained before and after arthrography. The MR imaging features of the ligaments and tendons about the CCMC and IMC and the joints themselves were analyzed in a randomized fashion, and correlated with those seen on anatomic sections. Results: Six CCMC ligaments were visualized. The dorsal and palmar CCMC ligaments, and the pisometacarpal ligament were best visualized in the sagittal plane. The radial and ulnar CCMC collateral ligaments, and the capito-third metacarpal ligament were best visualized in the coronal plane. Three main IMC ligaments were observed: a dorsal and a palmar ligament, and an interosseous ligament complex. All three ligaments were best visualized in axial plane. Four tendinous insertions to the metacarpal bases were evident. Conclusion: The anatomy of the ligaments and tendinous insertions about the second to fifth IMC and the CCMC joints is well demonstrated by MR imaging and MR arthrography. MR arthrography does not significantly improve the visualization of these complex structures.

MR imaging of the metacarpophalangeal joints of the fingers: normal MR and MR arthrography findings in cadavers N.H. Theumann 1 , C.W.A. Pfirrmann 2 , D. Resnick 3 ; 1 Lausanne/CH, 2 Zürich/CH, 3 San Diego, CA/US Purpose: To demonstrate the normal anatomy of the metacarpophalangeal (MCP) joints of the fingers with MR imaging and MR arthrography. Materials and methods: MR images of 20 MCP joints of the fingers derived from five fresh human cadaveric hands were obtained in the extended and flexed positions before and after arthrography. The MR appearances of all articular and periarticular structures were analyzed and correlated with those seen on anatomic sections. Two independent readers graded the visibility of these structures. Results: The main collateral ligaments could be best evaluated in the axial images with the fingers flexed. The accessory bands of the collateral ligament complex were best seen in the axial images with the fingers extended. The sagittal MR images were best for evaluating the palmar plate and the capsule. MR arthrography improved the visualization of all articular and periarticular structures. Κ values that related to MR imaging findings with all sequences rated moderate to substantial. The Κ values of the MR arthrographic sequences were slightly higher than those of unenhanced sequences. Conclusion: MR imaging and MR arthrography allow accurate visualization of the important anatomical structures of the MCP joints. MR arthrography enhances their visualization.

Normal and osteoarthritic pisotriquetral joint: Assessment with MR imaging and MR arthrography N.H. Theumann 1 , C.W.A. Pfirrmann 2 , D. Resnick 3 ; 1 Lausanne/CH, 2 Zürich/CH, 3 San Diego, CA/US Purpose: To demonstrate the MR Imaging and MR arthrographic findings of the pisotriquetral joint (PTJ) and its surrounding structures, and to evaluate the contribution of these examinations to the assessment osteoarthritis of the PTJ. Material and methods: MR images of 22 PTJ derived from fresh human cadaveric hands (12 woman, 5 men; age range at death, 45 -90 years; mean age at death, 75 years) were obtained before and after arthrography. The MR appearance of all intraarticular and periarticular structures were analyzed and correlated with those seen on anatomic sections. Two readers graded in consensus the visibility of normal structures and the severity of abnormalities of the joint.

Discrepancies in postoperative shoulder MR imaging M. Manisali, D. Ozaksoy, E. Yilmaz, A. Balci, C. Ozcan, M. Ozkan; Izmir/TR Purpose: To discuss the discrepancies between MR images and clinical findings in patients who had rotator cuff rupture on postoperative shoulder MR imaging. Methods and material: 31 patients who had pre-and postoperative MR images eligible for interpretation were included in this study. The mean of the time interval between surgery and MR imaging was 32 months. All patients had T1 SE (axial), T2 SE (paracoronal) and T2* GE (sagittal) MR images. In addition to routine sequences, preoperative (8 cases) and postoperative (5 cases) also had indirect MR arthrography with iv Gadolinium. In 3 cases with biceps tendonitis, routine imaging planes were modified. Depending on the results of the MR, the patients were divided into two groups; those with (group 1) and those without (group 2) rotator cuff rupture. We evaluated each group for constant score. These parameters were also compared with the preoperative status of the patients found from their notes. The differences between groups and changes in pre-postoperative clinical status were then analyzed statistically. Results: 39 % of the patients (12 out of 31) had rupture (6 complete, 6 partial). In 7 cases the ruptures were in the same preoperative localization. Constant scores for group 1 and 2 were 91.63 ± 13.26 and 83.42 ± 7.39 respectively, p < 0.3. Conclusion: MR imaging is a noninvasive alternative method to arthroscopy in the postoperative period of rotator cuff repair. However, there are some discrepancies between the results and clinical assessment, in which surgical technique, imaging plane, fibrotic changes and postsurgical physical therapy, may play important roles.

A. Scherer, B. Ostendorf, V. Engelbrecht, L.W. Poll, M. Schneider, U. Mödder; Düsseldorf/DE Purpose: Evaluation of MRI-findings in the metacarpophalangeal (MCP) joints in patients with early (eRA) and chronical rheumatoid arthritis (cRA). Material and methods: In 22 RA patients (9 with disease duration < 1.5 years … eRA) the dominant hands were examined by MRI in coronal T2 weighted turbo-spin-echo (TSE), T1 weighted spin-echo (SE) sequences before and after injection of Gd-DTPA and fat-suppressed short tau inversion recovery (STIR) sequences, followed by miniarthroscopy (MA) of the MCP II joint after an interval of 24-hours. MRI-and MA-findings were assessed using standardized semiquantitative items of synovial and bony pathologies and a statistical comparison between the eRA and cRA-patients was performed. Results: In MRI synovial proliferation was detected in 13/13 cRA-and 8/9 eRApatients. Being statistically not significant, the degree of synovial proliferation was lower in the eRA-group. All eRA-patients with synovial changes showed enhancement after administration of contrast medium, a marker which correlated with the clinical activity. In 2/13 cRA-patients no uptake of contrast medium was evident. Bony erosions and joint-space narrowing strongly correlated with disease duration and were significantly rarer documented in the eRA-patients (1/9, 2/9) than in the cRA-patients (9/13, 10/13). Conclusion: In RA-patients, MRI of the metacarpophalangeal joints can detect specific pathological changes, which are observed significantly more often in either early or chronic stages and which are associated with disease activity and duration.

Radiological and imaging assessment of total hip arthroplasty: A ten year retrospective study S. Petcu, I.-R. Negrea, V. Crisan, I.-R. Ivan, L. Florescu; Cluj-Napoca/RO Purpose: To re-evaluate the radiographic and CT criteria for pre-and postoperative assessment of total hip arthroplasty, to correlate the patients age and constitution with preoperative diagnosis, to establish the survival rate of the prostheses 5 and 10 years postoperatively and to identify the causes determining the revision. Methods and materials: The cases with Stryker and Metrimed type prostheses (276 arthroplasties and 19 revisions) were selected. The results were assessed clinically, radiologically and on CT immediately after surgery, at 6 months and then yearly or when necessary. Results: The mean age of the patients was 60.5 years. The preoperative diagnosis was primitive coxarthrosis (76 %), femoral neck fracture (16.3 %) and femoral head aseptic necrosis (6.52 %). Only 19 cases (6.88 %) required revision after 10 years for aseptic loosening (52.63 %), important osteolytic lesions (15.78 %), heterotopic calcifications (10.52 %), migration of the acetabular component (10.52 %), femoral diaphysis fracture (5.26 %) and dislocation of the prosthesis (5.26 %). The survival rate of the prostheses after 5 and 10 years was 98.91 % and 93.11 % respectively. Conclusions: Most revisions (84.21 %) were made for complications due to inadequate physical activity in young patients and to the damaging of the remaining bone in the elderly. Standard radiography remains the elective method for the assessment of arthroplasty, CT being required only for selected cases.

Method and materials: MR studies of 45 patients correlated with cadaveric anatomy and with arthroscopic findings were examined. The studies were obtained with a 1.5 T scanner (General Electric) using axial, sagittal, coronal fat suppressed T1-weigthed images and 3D acquisitions, and posterior 2D and virtual arthroscopy reconstructions. Results: The most common variations occur at the origin of the glenohumeral ligaments (GHL) and the insertion of the joint capsule. Among the GHL variants, the common origin of the superior and middle ligaments is the most frequent followed by thinning, thickening or absence of the middle glenohumeral ligament. Common variants of the labrum include foramen sublabrum and Buford complex. Anteroinferior dislocation is the most frequent cause of glenohumeral instability and produces several lesions such as anteroinferior labral tear and Bankart. Also common are superior labrum anterior-posterior (SLAP) lesions. Knowledge of normal variants is essential for accurate interpretation of MR arthrograms of the shoulder. MR arthrography is superior to other imaging techniques in the evaluation of glenohumeral instability. Conclusions: There are a significant number of variations of the normal anatomy that simulate pathologic conditions and represent diagnostic pitfalls at MR arthrography.

Initial study of 3D water-excitation magnetization transfer contrast MR imaging of articular cartilage H. Yoshioka 1 , P. Lang 2 , K. Ikeda 1 , M. Niitsu 1 , Y. Itai 1 ; 1 Tsukuba/JP, 2 Boston, MA/US Purpose: To investigate efficacy of three-dimensional (3D) water-excitation magnetization transfer contrast (MTC) MR imaging of the articular cartilage of the knee. Materials and methods: Three porcine knees and five volunteers knees were scanned using 3D water-excitation sequence (TR/TE/flip angle 28 ms/14 ms/20°) with and without 1-2-1 on-resonance MTC pulse at 1.5 T. As a clinical study, MR images of eight patients with osteoarthritis of the knee were examined and compared between 3D water-excitation MTC sequence and fat-suppressed 2D proton-density weighted fast spin echo (FSE) sequence (TR/TE 3043 ms/17 ms). Results: 3D water-excitation images with MTC pulse showed significantly higher contrast-to-noise ratio (mean ± standard deviation = 44.0 ± 6.17) between joint effusion and articular cartilage than those images without MTC (10.5 ± 8.81) (p < 0.05). In patients with osteoarthritis of the knee, joint effusion showed higher signal intensity than cartilage (arthrogram-like effect) on 3D water-excitation MTC images. The contrast between joint effusion and articular cartilage on 3D waterexcitation MTC images was similar to that on fat-suppressed FSE images. In addition, thinner section images without blurring were obtained on 3D water-excitation MTC images. Conclusion: 3D water-excitation MTC imaging will be a promising method to evaluate articular cartilage in osteoarthritis and cartilage defect within a reasonable scan time.

Is indirect MR arthrography worthwhile in MR evaluation of the shoulder? M. Vega, L. Martí-Bonmatí, F. Delgado, M. Graells, M.D. Serrano; Valencia/ES Purpose: To evaluate if indirect MR arthrography is worthwhile in the routine MR evaluation of degenerative shoulder abnormalities. Material and methods: One hundred patients referred for a degenerative shoulder MR evaluation were randomly divided into two groups (without and with contrast administration). MR images were obtained with a 0.5 T magnet. Both were studied with coronal PD and T2W, sagittal T1W and transverse T2*W images. To obtain indirect MR arthrography, gadolinium (20 ml) was iv injected 15 minutes before the MR examination. Different MR parameters (image quality, visualization and confidence in the diagnosis of labrum, ligaments and tendons) were evaluated. Statistical analysis was performed with the Mann-Whitney test. Results: Indirect MR arthrography was statistically superior to conventional MR in the overall image quality (p < 0.000), confidence in the evaluation of the coracoacromial ligament (p = 0.014) and superior gleno-humeral ligament (p = 0.046), and visualization of the superior gleno-humeral ligament (p = 0.037). There were no differences in the visualization and diagnostic evaluation of labrum, subescapular recess, other ligaments (coraco-clavicular, coraco-humeral, medial gleno-humeral) and tendons (biceps, supraspinous, infraspinous, subscapular) and joint effusion. Conclusions: Indirect MR arthrography and MR evaluation of the degenerative shoulder disease have similar results. The overall image quality and the diagnostic evaluation of the coraco-acromial and superior gleno-humeral ligament are better evaluated with indirect MR arthrography. The diagnostic relevance of increasing the cost of the examination with gadolinium administration must be prospectively evaluated. ;20:S67-S81) were evaluated by 3 radiologist: visualization of the glenohumeral ligaments (GHLs), origin and size of GHLs, morphology variants of the anterosuperior labrum, insertion of the biceps tendon, size and shape of the capsular recesses, and insertion of the joint capsule. Results: The superior LGH originated with the biceps tendon in two patients, was absent in one case and thick in another. The middle GHL was absent in 10 studies, originated with the superior GHL in one case, thick in tree cases, redundant in two, and Buford complex in one study. Presence of the sulcus under the anterosuperior labrum was seen in 4, sublabral foramen in 4 and superior sublabral recess in 3 cases. Variations of the capsular insertion were found in 7 cases and of the subscapular recess in 6 patients. Conclusion: Patients with glenohumeral instability have different normal variations of the GHLs, anterosuperior labrum, capsule and biceps tendon. Knowledge of these normal variants is essential for the accurate interpretation of CT and MR arthrography of the shoulder.

Diagnostic possibilities of new ultrasound technologies in the evaluation of chronic rotator cuff tears of the shoulder I.V. Dolgova, A. Zubarev, S. Arkhipov; Moscow/RU Purpose: To determine the role of the new ultrasound technologies in the ulrasonography in the diagnosis of chronic rotator cuff tears of the shoulder and to demonstrate the significance and effectiveness of these methods (with surgical and diagnostic correlation with artroscopy). Material and methods: A total of 47 patients presenting with a clinical rotator cuff tear of the shoulder were examined (age range 27 -56 years). All patients presented for treatment in 3 -6 months after appearance of the first clinical symptoms. Ultrasonography of the shoulder was carried out with the new ultrasound technologies: Sono-CT and volumetric 3D. Sonographic diagnosis was then compared with the final diagnosis at arthroscopy. Results: 17 patients had a chronic rotator cuff tear due to an old trauma. 30 patients had impingement syndrome with a rotator cuff tear. The sensitivity of conventional ultrasonography in the diagnosis of chronic rotator cuff tears of the shoulder was 77 %. The use of Sono-CT ultrasound technology allowed the sensitivity to raise up to 96 %. The specificity increased from 68 % to 95 %. Volumetric 3D did not change the sensitivity or the specificity, but allowed visualizing the rupture structure in the front view as well as estimating its localization and extension with respect to other anatomic shoulder parts.

The new ultrasound technologies are very useful and effective in diagnosis of the chronic rotator cuff tears of the shoulder and raise the sensitivity and specificity of the ultrasound method.

MRI pelvimetry in women previously operated on because of congenital hip luxation J. Mechlinska, S. Mazurkiewicz, B. Baczkowski, A. Zapasnik, M. Dubaniewicz; Gdansk/PL Congenital hip luxation (CHL), if diagnosed early, can be treated successfully with conservative procedures. In the past, before the introduction of routine prophylactic examinations, CHL was seen more frequently and was treated operatively. The purpose of the study was to find out if orthopaedic operations performed in childhood, have resulted in consequence changes to the dimensions of the female pelvis. 25 women (age range 20 -45 years) who had in childhood had undergone Pemberton's (10 cases), Salter's (10 cases) or Chiari's (5 cases) operations were examined with MRI (Gyroscan 0.5 T, Philips). T1 weighted, gradient echo images were obtained in 3 planes, with an imaging time of less than 4 min. In each patient the following distances were measured: on sagittal images showing the midline sagittal inlet and outlet were assessed; on axial oblique images transverse diam-

Carpal ligaments: detailed MR arthrographic appearance and observations relevant to the diagnosis of carpal instability N.H. Theumann 1 , C.W.A. Pfirrmann 2 , D. Resnick 3 ; 1 Lausanne/CH, 2 Zürich/CH, 3 San Diego, CA/US Purpose: To demonstrate the MR arthrographic anatomy of the carpal ligaments. Material and methods: High resolution MR images of 22 wrists derived from fresh human cadaveric hands were obtained after tricompartimental arthrography. The MR arthrographic appearance of the carpal ligaments and their bony attachments were analysed and correlated to that seen on anatomic sections. Two readers determined in consensus which was the best plane to observe the course and attachment sites for each ligament. They further analyzed the size and sites of attachment of these ligaments in the two orthogonal planes that were chosen in order to best demonstrate them. Results: Each ligament was well seen as hypointense linear structures with MR arthrography. The radioscaphocapitate, radiolunotriquetral, radioscapholunate, dorsal radiotriquetral, palmar scaphotriquetral, and dorsal scaphotriquetral ligaments were best evaluated in the axial plane. The palmar and dorsal ulnotriquetral and ulnolunate ligaments were best visualized in the sagittal plane. The radial collateral ligament was best analysed in the coronal plane. The attachment sites of all ligaments were best analyzed either in the axial or sagittal plane. Conclusion: MR arthrography allows visualization of the carpal ligaments. Detailed knowledge of the normal appearance of these ligaments will serve as a baseline for future studies in which MR arthrography is used to characterize wrist instability.

Pigmented villonodular synovitis of the foot: MR findings A. Iovane, M. Midiri, M. Galia, T.V. Bartolotta, A. Carcione; Palermo/IT Purpose: To assess the outcome of Magnetic Resonance Imaging (MRI) in the diagnosis and classification of Pigmented Villonodular Synovitis (PVNS) of the foot. Methods and materials: 753 MR studies of the foot performed at our Institute from June 1994 to April 2000 were retrospectively reviewed looking for PVNS. Spin echo (SE) T1W, Gradient echo (GE) T2*W, and Short Time Inversion Recovery (STIR) images were acquired with a 0.5 T superconductive unit provided with a dedicated extremities transmitter/receiver coil. The site and the type of lesions, signal intensity patterns, and the presence of associated changes were evaluated. Results: Six patients (3 men, 3 women, age range: 35 -48 years) affected by PVNS were selected. Three out of six PVNS were nodular forms whereas the remaining three were diffuse. The three nodular forms were respectively found one in the sub-talar joint and two antero-medially to the talus. All the diffuse lesions were located on the metatarsus. Perilesional edema was found in all cases, although more obvious in the nodular forms, whereas bone involvement (osteochondral erosion) was only observed in the diffuse metatarsal PVNS. Intraarticular bloody effusion was never observed. MRI findings were in all cases confirmed by surgery. Conclusions: Both MRIs high contrast resolution and multiplanar capabilities allow the complete evaluation of foot structures affected by PVNS. According to our results, MRI seems to be the most reliable technique both in the identification and classification of PVNS and in order to provide correct pre-therapeutic planning and effective treatment monitoring.

Knee injuries in football players compared to non-competitive patients on MR imaging E. Arana, L. Marti-Bonmati, A. Silvestre, F. Forriol; Valencia/ES Purpose: To compare MR imaging findings of competitive football players with those in a less active population of similar age, for identifying different injury patterns Material and methods: MR images were obtained from 1014 knees of competitive federated football players aged 21.2 ± 8.1 years (range, 14 to 29 years) in a 0.2 T Signa Profile. All knee structures were evaluated according to established grading criteria and compared with a group of controls matched for age and sex. This group consisted of 561 patients aged 22.1 ± 10.2 years (range, 15 to 30 years). All subjects underwent arthroscopy and those with previous knee surgery were discarded. Results: When compared with control group, the experimental group of footbal players had a significantly different distribution ( 2 , p < 0.001) of medial menisci (MM) tears (472 vs. 186). Also, hemarthrosis, tear of medial ligament complex (MCL) and osteochondral fractures were more prevalent in the competitive than in the recreational sport group ( 2 test, p < 0.001, p = 0.004 and p = 0.005, respectively) The prevalence of grade 2 intrameniscal signal abnormalities was clearly higher in football players compared to non-competitive subjects (33 % vs. 12 % in medial meniscus, and 26 % vs. 8 % in lateral meniscus 2 test p = 0.001 and 0.002 respectively). Conclusion: Knee injuries produced by competitive sports follow a different pattern than those sustained from casual injuries or during recreational sport. Knee injury for sporting activity is more likely to result hemarthrosis, a MM or an MCL tear. Grade 2 meniscal signs reflects probably accelerated degeneration in this population age of competitive football players. To study the possibility of using radiographs, photodensitometry and CT with histographical analysis to reveal osteoporosis, and to assess the utility of sonography in the detection of joint changes in patients with RA. We aimed to evaluate bone density and the state of calcium metabolism in RA and podagra. Methods and materials: Densitometry of the standardized radiograms of hands and feet together with aluminium stendwedges was conducted in 120 patients with RA and 40 patients with podagra. The serum concentration of total and ionized calcium, phosphorus and their regulating hormones was determined by radioimmunological analysis. 25 patients with RA were examined by CT with histographical analysis of lumbar vertebrae density, 30 by ultrasonography of knee joints. Results: The reduced bone density was revealed in 108 patients with RA, including 34 persons without evident radiological sings of disease. Bone density in patients with podagra did not differ from that of the control group. Impairments of calcium and phosphorus metabolism and its regulating system have been determined in the both patients groups. The histograms of lumbar vertebrae density inpatients with RA had a 1.5 -2 times wider base than those of healthy persons. The articular joint space narrowing, the bone erosion and fluid in the articular cavity were revealed using knee joint ultrasonography.

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Conclusion: Radiogram photodensitometry may be used for differential diagnosis of RA and podagra in their early stages. Results of CT histographical analysis indicated hypertrophical character of osteoporosis in RA. Impairments of calcium and phosphorus metabolism are determined in RA and podagra.

Developmental displacement of the hip in newborns and infantssystematic sonoscreening A. Zvezdin, L. Petkovic, G. Spanovic; Novi Sad/YU Purpose: Early diagnosis and treatment of developmental displacement of the hip (DDH) requires systematic and routine clinical and ultrasonographic examination of newborns and infants. The Grafs methodological procedure was applied and clinical/sonograph clasification of DDH. The aim of this work was to confirm valuation of US diagnosic procedure and Grafs methodological procedure of hip categorisation in newborns and infants. Methods and materials: In period from 1992 to 1998; 11550 patient were underwent ultrasonographyc examination of the hip. Routine tehnique of examination consists of hip arthrosonography in sagittal and in lateral positions with linear transducer, 7.5 MHz for newborns and 5 MHz in infants. The procedure was performed in frame of primar (for newborns) and secundar sonoscreening for infants. Method and materials: 32 patients affected by "coxa-pedis syndrome" entered this study. All the patients were previously submitted to plain film examination and in 9 cases CT scans were also performed. The sequences employed both on 1.5 T whole-body unit and on 0.2 T dedicated unit were SE T1 and T2-w (also with fat saturation pulse) and GE T2-w on sagital and axial scan planes, slice thickness being 3 -4 mm. Results: MRI examination showed a posterior tibial tendon injury in 21 patients associated with the presence of an os tibiale in 7 cases. In 2 cases a complete spring ligament tear was discovered while in 1 patient we documented a partial morphological recovery of an injuried spring ligament after four months. In the last 8 patients MRI examination revealed the presence of talo-navicular osteo-chondral pathology. Conclusion: Many pathological conditions may involve the talo-calcaneo-navicular complex. On the basis of our experience MRI examination allows an easy differential diagnosis, tendon involvement being the more frequent condition found in patients clinically suspected of having the so-called coxa-pedis syndrome.

Knee MRI after complicated anterior cruciate ligament reconstruction correlated with arthroscopic findings V. Barrau, N. Sans, J.-J. Railhac, P. Bonneviale, H. Chiavassa-Gandois, D. Galy-Fourcade; Toulouse/FR Purpose: To evaluate MRI efficiency to find causes of knee pain after ACL reconstruction. Material and methods: During 2 years, 24 consecutively collected knee MRI were realised for knee pain after ACL reconstruction. Conventional, sagittal and coronal proton density and T2-weighted turbo spin echo sequences, sagittal inversion recovery were realised. When needed, sagittal post gadolinium with fat saturation was added. The MR readers were blinded to clinical and arthroscopic findings. The results of all 14 patients who had a second arthroscopy were correlated with MR findings. Results: We report complications of the graft: 3 complete disruptions, 1 impingement syndrome, 3 cyclops, 1 malposition of the screws. The PCL was disrupted in two cases, bone complications occured as osteomyelitis in one case, algodystrophy (n = 2), degenerative osteoarthritis (n = 4), bone contusion (n = 2). Synovitis was found in 3 cases, articular effusion in 3 cases and synovial cysts in 2 cases. Abnormalities of the cartilage (n = 5), of the menisci (n = 8), of the pararticular tissues (Hoffa fat pad (n = 2), of the tendons (n = 2)) are also illustrated. Global MRI accuracy compared to the arthroscopy was 86 %. Conclusion: MRI is an effective method for the diagnosis of knee pain after ACL reconstruction, a large number of these complications are illlustrated in this poster.

Virtual arthroscopy of the wrist B.E. Dogan, G. Sahin-Akyar, M. Demirtas; Ankara/TR Purpose: The aim of this study is to reveal if virtual MR arthroscopy could be used to visualize the internal architecture of the radiocarpal compartment of the wrist joint in a similar manner to surgical arthroscopy. Methods and materials: 20 patients with chronic ulnar sided wrist pain were evaluated with MR arthrography prospectively. Diluted paramagnetic contrast material was injected to the radiocarpal compartment prior to MR examination in all patients. A fat-suppressed T1-weighted three-dimensional fast spoiled gradient echo (3D Fast SPGR) sequence was acquired in addition to our standard imaging protocol in each patient. Data sets were then transferred to an independent workstation and were post-processed using navigator software to generate surface rendered virtual MR arthroscopic images. The threshold necessary to visualize the internal surfaces of the radiocarpal compartment was adjusted individually for each case. Results: Virtual MR arthroscopy of the radiocarpal compartment of the wrist joint was demonstrated in 15 out of 20 patients (75 %). Conventional MR arthrography revealed triangular fibrocartilage tears in 10 patients, scapholunate ligament tears in 2 patients, 8 (67 %) of which were shown by virtual MR arthroscopy. Conclusion: Although preliminary, our work suggests that virtual MR arthroscopy shows promise in visualizing the internal morphology of the radiocarpal compartment and in demonstration of triangular fibrocartilage tears. Further work correlated with surgical results is required to assess the ultimate value of the technique in evaluating the wrist pathologies, and to see if viewing of the MR data from an intraarticular perspective adds to the final diagnosis.

Anterior cruciate ligament (ACL) injury: Our experience with sonographic evaluation W. Krzyzanowski, B. Grzechnik, K. Gaweda, R. Pietura, M. Szczerbo-Trojanowska; Lublin/PL Purpose: To assess a usefulness of ultrasound (US) in the diagnosis of ACL damage in prospective correlation with arthroscopy and MR imaging. Material and methods: Between 1997 and 2000, 311 patients with knee trauma were referred for US examination. All patients had plain radiography to exclude bone fracture. 56 patients were clinically suspected as having an ACL injury. US was performed using linear transducer of 5 -10 MHz frequency. Additionally a group of 40 healthy volunteers underwent US examination of both knees (80 knees) to determine the normal sonographic appearance of ACL. In both groups the US examination of ACL included assessment of sonomorphological features (outlines of visible ACL portion, echogenicity of intercondylar notch) and dynamic evaluation during gradual knee flexion from 80° to possible maximal bend (own modification). All patients underwent MR imaging of the knee (1.5 T scanner) and arthroscopy. Results: The diagnostic efficacy of US in the detection of ACL damage and differentiation of its degree was generally 76.2 % in comparison to arthroscopy. Accordance of US and MRI was 89 % in diagnosis of ACL rupture but only 40 % for partial injury. Conclusions: US is a valuable modality in assessment of ACL, very helpful in patients with uncertain clinical signs of ACL injury, especially in acute phase following trauma. Good efficacy of assessment can be achieved when both morphological and dynamic examination is performed. 

In 180 patients (58 %) the presence of a meniscal abnormality in the injured knee was clinically suspected. All patients had MR imaging of the knee (1.5 T scanner) and 83 patients underwent arthroscopy. Results: US examination enabled the discover of different meniscal abnormalities such as: tears, cysts, degeneration foci, meniscocapsular separation, subluxation and discoid menisci. US examination results were generally consistent with arthroscopic findings in 80 % of cases for medial meniscus and 90 % for lateral meniscus. MR imaging confirmed US diagnosis in 94 % and 91 % for each meniscus, respectively. Conclusions: US is valuable modality in diagnosis of meniscal lesions. It is especially useful in depiction and accurate preoperative assessment of meniscal cysts.

Hip To determine which part of the femoral neck length contributes most to the fracture risk and to define a geometric parameter superior over hip axis length (HAL) for discriminating hip fracture patients. Materials and methods: Forty-nine Caucasian women with a non-traumatic femoral neck fracture (fractured group) were matched on age to 49 normal women (control group) and on both age and femoral neck BMD to 49 unfractured women (low-BMD unfractured group). Hip DXA was performed with standard protocols. Besides BMD, geometric parameters (neck-shaft angle, neck width, and several HAL segments) were evaluated by logistic regression analysis to determine the best discriminator of hip fracture. Results: Age-related bone loss was associated with a neck width increase in low-BMD patients. HAL was significantly longer in fractured patients and was a highly significant discriminator between fractured patients and normal controls. Along neck axis, the intertrochanter-head center distance offers advantages over other reported neck lengths. It produced the highest odds ratios for hip fracture when low-BMD unfractured patients were used as the reference (OR = 1.72; CI = 1.09 -2.71). The intertrochanter-pelvic rim length produced odds ratios (OR = 1.63; CI = 1.02 -2.60) for hip fracture that were only slightly lower than those for the intertrochanter-head center distance and higher than those for HAL. Conclusion: The intertrochanter-head center distance coincides with the femoral lever arm, and was the best discriminator between fractured and low-BMD patients. Because the center of the femoral head can be difficult to determine automatically, the intertrochanter-pelvic rim length may be an alternative to the intertrochanter-head center distance.

Direct arthrography of the pisotriquetral joint in patients with chronic ulnar wrist pain related to pisotriquetral osteoarthritis E. Pessis 1 , J.-L. Drapé 1 , N.H. Theumann 2 , D. Godefroy 1 , F. Bach 1 , A. Feydy 1 , A. Chevrot 1 ; 1 Paris/FR, 2 Lausanne/CH A Communication between the pisotriquetral joint (PTJ) and the radiocarpal joint (RCJ) is a common finding. For patients with chronic ulnar wrist pain related to pisotriquetral osteoarthritis direct arthrography in the PTJ is needed for steroid injection when there is no communication between the PTJ and the RCJ. This exhibit will illustrate a safe and easy procedure for intra articular steroid injection in the PTJ under fluoroscopic guidance using a medial approach. For 12/32 patients with with chronic ulnar wtist pain related to pisotriquetral arthritis a direct access to the PTJ was obtained with the hand in extreme prone position. The needle was positioned directly into the PTJ under fluoroscopic guidance. Direct injection of the PTJ was successful in 12 of the 12 cases. Repositionning of the neeedle for soft tissue extravasation of contrast medium, or excessive pain was not necessary. Results: Regression analysis showed significant correlation (p < 0.005) of the cross sections of ACL to the anterior notch inlet and posterior notch outlet area and a significant correlation (p < 0.05) to the intermediate notch plane. The NWI showed a significant correlation (p < 0.05) only to the anterior notch inlet. No correlation between height and weight of the volunteers and the ACL was noted. Conclusions: The smaller the intercondylar notch, the smaller the width of the ACL. A biomechanically weaker ACL may predispose patients with small intercondylar notch to ACL rupture. In contrast to other authors our results show a preference for the inlet and outlet areas of the notch to be correlated with the ACL size.

High-resolution ultrasonographic examination of the elbow joint R. Landeras, M. Fernandez, F.J. González, P. Lastra, P. Sadaba, A. Canga; Santander/ES High frequency ultrasonography is a rapid, inexpensive and non invasive technique for the evaluation of the musculoskeletal system. An overview of the US normal anatomy and pathologic conditions of the elbow is presented with clinical radiographic and MR correlation. Paradigmatic US images from different pathologic entities of the elbow (intrarticular loose bodies, joint effusions, dislocation, acute infection and inflammatory diseases, tendon pathologies, ulnar nerve injuries in the cubital tunnel and tumours) are showen. We assess the role of the US in the management of these lesions. US studies were performed with 7.5 -10 MHz high resolution linear array transducer. The introduction of color Doppler flow imaging allows visualization of areas of hyperperfusion specially in inflammatory, infectious and tumoral diseases.

Brain C-0611 CT scan, magnetic resonance imaging and proton MR spectroscopy findings of brain abnormalities in Wilson's disease I. Lupescu, F. Preoteasa, O. Amza, C. Rotaru, M. Grasu, C. Zaharia, S. Georgescu; Bucharest/RO Purpose: The aim of this study is to describe the CT scan, MRI and H + MRS aspects of cerebral changes in hepatolenticular degeneration. Materials and methods: Two patients (1 male and 1 female, 21 and 23 years old) with non specific neurological symptoms (tremor, speech problems, bradykinesia) and elevated free serum copper concentrations were evaluated by cerebral CT scan (Somatom Plus, Siemens) and MRI of the brain (Signa Horizon, GE, 1.5 T) using PD, T2, FLAIR and T1 weighted sequences slices in the three orthogonal planes. For H + MRS we have used a multivoxel PRESS SI and single-voxel STEAM sequences at globus pallidus level. Kayser-Fleischer rings were present in one case.

The density (hypodensity) and signal intensity changes (low signal intensity T1, high signal intensity T2) were bilateral and symmetrical, located in the thalamus, globus pallidus, caudate nucleus and one of the two cases presented white matter and brain stem lesions (tegmentum of the mid brain and pontine tegmentum). The H + MR spectra findings are lacking mI (mio-Inozitol) depletion and glutamine accumulation. Conclusions: MRI is the method of choice for diagnostic and monitoring of Wilson's disease. In patients with elevated serum and urinary copper concentrations, the MRI and H + MRS aspects confirm the diagnostic of hepatolenticular degeneration.

Three-dimensional brain surface display using multislice CT T. Hirano, S. Tanabe, M. Ohtaki, M. Bandoh, N. Yama; Sapporo/JP Three-dimensional (3D) images of the brain surface were generated using the volume-rendering method. The quality of such 3D-CT surface images was compared between multislice CT and single-slice CT. 3D-CT surface images were also compared against magnetic resonance (MR) images. The subjects in this study were 7 patients with cerebral arteriovenous malformations, 3 patients with parasagittal meningiomas, and 3 healthy subjects who were examined by MR angiography at the same time as CT angiography in 1998 or later. 3D-CT surface images and 3D-MR surface images were generated, and the depiction of sulci, gyri, and venous structures on the brain surface was evaluated. Because CT images of the brain surface are affected by partial volume effects, multislice CT with a 0.5 mm slice thickness is able to provide far better results than conventional single-slice CT 3D. In addition, multislice CT, which has a higher S/N, permits the venous system on the brain surface to be visualized without the use of contrast medium. Comparison against 3D-MR surface images with regard to imaging of the sulci and gyri showed that multislice CT was able to provide comparable results. 3D-CT surface images obtained using multislice CT are able to provide more information than 3D-MR surface images in patients with cerebral arteriovenous malformations or parasagittal meningiomas. In addition, multislice CT allows the venous system on the brain surface to be visualized without contrast medium, and is thus expected to provide clinically useful images in patients in whom the use contrast medium is contraindicated.

Joubert's syndrome vs rhombencephalosynapsis: Differentiation on the base of MRI findings S. Cakirer, M. Basak, A. Mutlu, O. Kilickesmez; Istanbul/TR Purpose: Joubert's syndrome and rhombencephalosynapsis are both rare congenital abnormalities related to vermian dysgenesis, with similar clinical findings related to cerebellar dysfunction. We present two patients with these disorders and discuss both the similarities and differences in between them on the basis of MRI findings.

A 4 year-old male patient with mental motor retardation, abnormal eye movements characterized by ocular apraxia in horizontal directions, and history of attacks of hyperpnea during the first few months of life, and a 7 month-old female patient with hypotonia, irritability and nystagmus were included in this study. MRI examination of the cranium was performed for each patient with SE T1, FSE T2, FLAIR sequences in three orthogonal planes on a 1.5 T MR scanner. Results: MRI studies of both patients revealed vermian agenesis. The patient with Joubert's syndrome showed agenesis of the vermis with a cleft formation, thick and elongated cerebellar peduncles with an almost horizontal course, and a deep posterior interpeduncular fossa leading to the appearance of molar teeth sign. The fusion of cerebellar hemispheres, cerebellar dentate nuclei, and superior cerebellar peduncles across the midline was present in the patient with rhombencephalosynapsis. Conclusion: Although the vermian agenesis is a common MRI finding in both Joubert's syndrome and rhombencephalosynapsis, the associated posterior fossa findings on MRI help us to differentiate in between these two disorders.

Prognostic value of magnetic resonance in patients with diffuse axonal injury (DAI) A. Carvajal, M. Martínez, M. Zauner, R. Peña, A. Rovira, V. Medina; Sabadell/ES Purpose: Three types of Diffuse Axonal Injury (DAI) have been recognized in severe head injury (SHI) in correlation with three major anatomic areas: DAI type 1 with axonal injury in the white matter of the cerebral hemispheres, DAI type 2 with focal lesion in corpus callosum; and brain stem lesions (DAI type 3). Cerebral magnetic resonance (MR) has been shown sensitive for detection and characterization of these lesions. The correlation between MR DAI types and the Glasgow Outcame Scores (GOS) are presented and discussed. Methods and materials: We performed a prospective study between Jan 1999 and Aug 2001, with 17 patients with SHI and discrepancy between the normal CT and the neurological status defined as: no hypertension and abnormal awake when withdrawing sedatives. MR was performed at medium of 10 days after injury to detect DAI type lesions. We compared the MR findings with the GOS at 6 months. Results: In 15 patients (88 %) MR demonstrated DAI type lesions. The GCS was lower in patients with DAI type 2 and 3, than in patients with DAI type 1. The correlation between DAI groups and the GOS are shown. Conclusion: MR is a sensitive method in detection of DAI type lesions. There is a good correlation between the GCS, DAI type lesions and GOS at 6 months. More than 50 % of patients with DAI due to SHI had a good recovery at 6 months. Despite the few patients with DAI type 1 lesions it seems that they have a better prognosis.

Detection quiz. Searching for the early CT signs of acute cerebral ischemia A.N. Chalazonitis, E. Katsianou, V. Dermentzoglou, A. Papaioannou, V. Zambiozi, P. Chronopoulos; Athens/GR Despite the development of advanced imaging techniques (xenon CT and MR imaging), CT remains the emergency imaging modality of choice to facilitate earlier diagnosis of acute cerebral ischemia. The aim of this exhibit is to allow radiologists to hone their own skills in the detection of these early CT signs. Ten cerebral nonenhanced CT images presenting asymmetric hyperdense arteries (acute thrombus formation) and/or development of vasogenic edema within the brain parenchyma are shown. Another ten cerebral nonenhanced CT images of the same patients, performed at least 24 hours after the onset of the clinical symptoms are also shown. The attendee will test his/her own ability by matching both images of the same patient. All cases were selected from our Hospital teaching files as part of the typical follow up that we perform for these patients. The attendee will try to identify early CT signs of acute ischemic cerebral infraction by testing his/her own detection skills. A list of the correct answers will be provided at the end of the exhibit.

Endovascular treatment of ruptured intracranial aneurysms using Cook "detach" coils system J.M. Pumar, J.A. Castiñeira, C. Seoane, B. Vázquez, M. Blanco, D. Abal; Santiago de Compostela/ES Purpose: To assess the feasibility and efficiency of the endovascular treatment by detach coil system (Cook). Material and methods: 30 patients (18 male, 12 female) presenting with SAH secondary to aneurysm rupture were treated by the Cook coil system, during one year. All procedures were performed in emergency conditions and transcranial oximetry was performed. Results: More than a 98 % occlusion of the aneurysm cavity was obtained in 22 aneurysms, 90 % or less in 5, 80 % or less in 2, and no coil was placed in one. The J-Coil suits all sizes of aneurysms due to its nature of adjusting its expansion accordingly. Transcranial oximetry deteted vascular spasm in 2 cases Conclusions: The Cook "Detach" coil system appears safe and fast for the its use in endovascular repair of cerebral aneurysm.

Imaging of perception deafness E. Menif, W. Douira, W. Zouaoui, O. Azaiz, K. Chelaifa, I. Turki, R. Slim, S. Hachicha; Tunis/TN Introduction: Hearing loss is a frequent reason for patients seeking a medical consultation. We aimed to define, for presentations of unilateral or bilateral and asymmetrical perception deafness, the clinical and functional selection criteria for proceding to an MRI. We also aimed to specify the MR imaging protocol. Material and methods: We present a prospective study involving 600 consecutive patients (mean age 42 years). All patients had a detailed clinical history taken and had a complete clinical examination. Subsequent MRI included T2W brain imaging, a CISS 3D sequence and T1 high resolution sections before and after Gadolinium administration. A correlation between functional tests results and MRI findings was established. Results: 10 % of exams were pathological, dominated by tumoral pathology: acoustic neurinoma (60 %), meningioma and primitive cholesteatoma. Other pathologies were found: cochlear ossification, metastasis to the cerebellarpontine angles, hemangioblastoma of the fourth ventricular floor, tuberculous arachnoiditis, cerebral tuberculosis, inner ear malformation, neurovascular contact and intralabyrinthine hemorrhage. Functional tests association had a negative predictive value of 98 %. Conclusion: It is important to make a careful clinical examination and to emphasise functional testing amongst old patients. In young subjects and before surgery of invalidating MENIERE, a full protocol MRI must carried out in all cases.

Clinical applications of high-resolution bold venography J.R. Reichenbach 1 , C. The recent development of a new high-resolution MRI approach to noninvasively visualize small veins in the human brain is reviewed. Following an explanation of the underlying bulk magnetic susceptibility effects, successful applications of the method are demonstrated in the imaging of the venous vascular aspects of different intracranial lesions. Methods and material: Imaging of volunteers and patients with different vascular malformations, brain tumors and metastases was performed on a 1.5 T scanner. To create BOLD venographic images a 3D gradient-echo, T2*-weighted, low-bandwidth sequence with first-order flow compensation in three directions was used (TR/TE/FA 45 -57/25 -40/25°). Between 32 to 64 partitions with a thickness of 1.5 or 2 mm were usually acquired with a FOV ranging between 240 and 270 mm and an in-plane resolution of approximately 0.5 mm × 0.5 mm. To reduce scan time in-plane resolution can be reduced to 0.5 mm × 1 mm, especially in patient studies. Magnitude images were masked with corresponding phase images to enhance venous contrast. A minimum intensity projection was performed over targeted volumes. Results: Highly detailed venous vascular information was obtained with BOLD venography. One advantage of BOLD venographic imaging is the simultaneous, spatially highly resolved depiction of the anatomy and vessels on the projection images, which can be valuable for clinical assessment. Conclusion: The ability to highlight deoxygenated blood with high spatial resolution yields important information which may have special significance for questions related to spatial resolution and selective representation. BOLD venography may thus lead to a better understanding of brain function in diseased states. 

We performed transcranial oximetry (TCCO) using an Invos 4.100 cerebral oximeter: The calculation of the regional cerebral saturation (rSO2) was performed based on spectroscopic data from multiple wavelengths collected by two detectors in the sensor pad. The recordings were taken on the forehead on either side of the midline. We monitored 30 patients with cerebral aneurysms treated by endovascular embolization. Cerebrovascular saturation measurements were stored every 5 seconds during the neurovascular procedure. Results: 12 patients showed small changes in rSO2 without any clinical relevancy. 2 patients showed a persistent decrease of rSO2 associated with vasospasm and aneurysm rupture. Conclusion: TCCO is a non invasive method considered useful in the monitoring of neurovascular procedures. 

We performed a retrospective study and reviewed computed tomography (CT) and/or magnetic resonance (MR) imaging findings of patients who were referred with a clinical diagnosis of stroke over a period of 3 years. We selected 18 cases in which the abnormal findings on CT and/or MR images corresponded to a particular vascular distribution in the posterior fossa. Imaging findings were then correlated with specific cerebellar and brainstem stroke syndromes. Results: The most commonly affected vascular distributions are: posterior inferior cerebellar artery (n = 6), anterior inferior cerebellar artery (n = 1), superior cerebellar artery (n = 4), brainstem perforators (n = 4), vertebrobasilar territory (n = 1), not classifiable (n = 2). We illustrate posterior fossa ischemic strokes in acute, subacute and chronic phases. In the acute stage, MR imaging with diffusion-weighted scans is most useful. We then correlate the anatomical distribution of the infarct with clinical neurological findings. Conclusion: Infarctions in the posterior cranial fossa reflect the vascular supply and distribution to this region. Familiarity with the patterns of infarction and their appearance on CT and/or MR imaging will help the radiologist to recognize these infarcts and in turn help them to correlate the specific stroke syndromes with the radiological findings. (1) To illustrate, by magnetic resonance (MR), the unusual non-tumoral lesions referred to this anatomical area. (2) To describe the normal anatomy and different elements of the hypothalamic-pituitary axis (HPA), indicating the differential diagnosis of each one. Practical diagrams and drawings are reported. Materials and methods: We reviewed the non-neoplastic lesions archived on the data bank of our hospital from May 1998 to May 2001. All cases were performed on a MR 1.5 T unit in sagittal and coronal projections. Results: Non-neoplastic lesions are low frequency pathologies of the HPA, affecting to the hypothalamus, pituitary gland, infundibulum, tuber cinereum, chiasmatic and suprasellar cisterns, and cavernous sinus. The infrequent lesions we have encountered are: internal carotid artery aneurysm, granulomatosis, arachnoid cyst, Rathke's cleft cyst, pituitary hyper/hypoplasia, neurohypophyseal ectopy, empty sella, hamartoma, acute and chronic inflammatory disease (meningitis, sarcoidosis, abscesses, hypophysitis, cysticercosis), carotid-cavernous fistula. All these entities were reviewed and graphically documented, emphasizing in their radiological features and their differential diagnosis. Conclusion: Thin section MR imaging has become the primary imaging modality for evaluation of the HPA, because of its high contrast resolution and multiplanar projections. Non-tumoral lesions, although uncommon, are quite well depicted under this technique and must be considered in differential diagnosis of HPA lesions.

Perfusion-CT determination of penumbra and infarct in acute stroke patients: From cerebral perfusion maps to a clinical prognosis M. Wintermark, O. Cuisenaire, J.-P. Thiran, P. Maeder, P. Schnyder, R. Meuli; Lausanne/CH Purpose: To develop a analysis software relying on the central volume principle for perfusion-CT examinations in acute stroke patients Methods and material: Our perfusion-CT software uses a step-by-step graphical interface to display the results. It affords an automatic or supervised choice of the reference arteries and vein and for a selection of different arteries for regional deconvolution. The interface was developed with the VTK (Visualization Toolkit) library from Kitware, which is a C++ library containing a large variety of multidimensional image processing procedures. We chose to wrap VTK library in Tcl/Tk, allowing our software to be recompiled and posted on many different hardware architectures (MS Windows family, Linux, SGI IRIX, SUN Solaris, …) Results: Our perfusion-CT software is user-friendly and allows for rapid processing of perfusion-CT data. It leads to mean transit time (MTT), regional cerebral blood volume (rCBV) and flow (rCBF) maps, demonstrated as quantitatively accurate by comparison with stable Xenon-CT. The deduced prognostic map, displaying the extent and location of reversible penumbra and irretrievable infarct, is correlated with delayed DW-MR. It allows to predict the clinical condition improvement that can be expected, through a parameter called potential recuperation ratio (PRR). Conclusion: The purposes of this computer exhibit are: 1) To get accustomed with rCBV, MTT and rCBF notions. 2) To discuss the choice of data acquisition parameters and of the best reference artery for the central volume principle in the various clinical conditions. 3) To evaluate the impact of perfusion-CT studies in the management of acute stroke patients.

Comparative assessment of the diagnostic possibilities of PET with 18 F-FDG and 11 C-butyrate for investigation of pathological volume brain formations (PVBF) and cerebrovascular disorders N.A. Kostenikov, L.A. Tyutin, N.P. Fadeev, V.E. Savello, D.V. Ryjkova, A.A. Stanzhevsky; St. Petersburg/RU The aim of the study was to investigate the feasibility of PET with 11 C-Butyrate in differential diagnostics of PVBF compared with 18 FDG-PET. We used Tumor/Non-tumor (Grey Matter) Ratio (T/NT) as an index for Semiquantitative data analysis. 2D-PET scans (Ecat Exact 47) with attenuation correction were performed in 86 patients with suspicion of PVBF. 30-min dynamic scans were carried out immediately after intravenous administration of 250 -350 MBq 11 C-Butyrate. 20 min 18 FDG-PET static scans were performed in 86 patients 30 min post injection of 185 MBq 18 FDG.

In 21 out of the 86 patients the malignant brain tumors had been discovered, in 41 benign tumors, in 3 arteriovenous malformation, in 7 stroke disease and in 14 postoperative cysts. The diagnoses had been verified histologically and morphologically. In 19 out of the 21 patient with malignant tumors 18 FDG-PET T/NT was high (> 1). In patients with benign tumors 18 FDG-PET T/NT was 3.7 times lower and in non-tumors patients 4.8 times lower than that in malignant tumors. The T/NT in case of 11 C-Butyrate and 18 FDG studies proved to be comparable for all studied types of tumors. For cases of benign meningiomas and adenoma of hypophysis 11 C-Butyrate T/NT was much higher (> 1). Dynamic 11 C-Butyrate-PET may help to find the difference in tumor and non-tumor vascular volumes by assessment both the vascular and tissues compartment of the PVBF. The higher washout rate of the [ 11 C] from tumors was considered as an additional criteria for differentiating of T/NT formations of the brain.

3D-tractography with diffusion tensor magnetic resonance imaging T. Homma, M. Adachi, A. Suzuki, T. Hosoya; Yamagata/JP Purpose: To evaluate the visualization of the pyramidal tract, superior cerebellar peduncle, and inferior cerebellar peduncle by 3D-tractography with diffusion tensor magnetic resonance imaging. Methods and materials: In 41 patients without any brainstem lesions, diffusion anisotropy maps were obtained by using 2 different thicknesses of the sections and intersection gaps (3 mm thick sections with 0 mm thick intersection gaps and 5 mm thick sections with 2.5 mm thick intersection gaps) in 9 directions. We then constructed 3D-tractography using both the surface rendering and volume rendering methods. Pyramidal tract, superior cerebellar peduncle, and inferior cerebellar peduncle were classfied by visual clearness into 3 degrees: (1) good, (2) fair, and (3) poor. Results: We can demonstrate these structures, especially the superior cerebellar peduncle, more clearly by 3D-tractography using 3 mm thick sections with 0 mm thick intersection gaps. Conclusion: Our findings show that 3D-tractography with diffusion tensor magnetic resonance imaging may be a useful tool in the demonstration of fibre tracts.

A quantitative approach for evaluating abnormalities of cerebral myoinositol and N-acetylaspartate in Alzheimer disease (AD) J. Ostojic, I. Vukadinovic, K. Koprivsek, D. Bogdanovic, A. Zvezdin, M.B. Prvulovic; Sremska Kamenica/YU Purpose: Our goal is to quantify abnormalities in cerebral neurochemistry and metabolism in patients with AD, using 1 H MRS. In the 1 H spectra of the brain in the elderly population, all metabolite concentrations are often reduced. The use of peak ratios correctly reflects relative changes rather than absolute increments or decrements. this aspect of diagnosis becomes clearer when quantitative MRS is applied. Materials and methods: Twelve healthy elderly (age 68.7 ± 7) demonstrated to be normal in neuropsychological tests, MRI and cerebral blood flow studies, were compared to 11 patients who met research criteria for AD. Using a Siemens Magnetom 1.5 T unit, two voxels of 12.5 -15 cm 3 were examined: (1) White matter (WM) in an area thought to be involved in AD (posterior parietal cortex); (2) Grey matter (GM), in an area relatively spared in AD patients (occipital cortex). A STEAM 20 sequence was used for spectral acquisition. Absolute metabolite concentrations were calculated using method of external standard, normalizing to the known concentration of acetic acid in a spectroscopy phantom. Conclusions: All patients with epileptic seizures present with cerebral haemodynamic changes of some degree, which are diagnosed most precisely after functional tests. Examination of epileptic patients must include complex neuroimaging as well as functional haemodynamic examination. This helps to diagnose not only the cerebral tissue structure, but also the changes in cerebral haemodynamics.

Multidetector 3D-CT angiography with volume rendering to evaluate the anatomy of cerebral aneurysm F. Cademartiri 1 , M.L. Dijkshoorn 2 , M. de Booy 2 , H.J. Thange 2 , D. Hasan 2 , A. van der Lugt 2 ; 1 Parma/IT, 2 Rotterdam/NL

The objectives of this study are: (1) to present a protocol for the study of the neck of brain aneurysms with volume rendering based on a CTA scan, (2) to show the difference between VR-CTA and DSA regarding the qualitative assessment of the neck of brain aneurysms, (3) to demonstrate the pitfalls of VR-CTA in the demonstration of the neck of brain aneurysms. DSA is the standard imaging technique to detect cerebral aneurysms and to evaluate the local anatomy (shape, size, neck, location and orientation). Of particular importance is the presence of an aneurysmal neck. This is key in decision making regarding the optimal surgical technique and whether the patient is suitable for coil placement. CTA with volume rendering is able to demonstrate the shape, size, location and orientation of the aneurysm and the presence of an aneurysmal neck. Multidetector CT data acquisition will further improve the image quality of subsequent post-processing techniques. This exhibit demonstrates the use of volume rendering with multidetector CTA data in the evaluating of cerebral aneurysms. Multiple VR algorithm have been applied (direct VR, thick slab VR, multiplanar VR) and are demonstrated. VR and DSA images are compared.

Follow The initial MR examinations were performed at the time of clinical diagnosis (age range: 1 week to 9 months). The follow-ups were performed at 5 to 36 months of age (interval periods: 3 -33 months). 1 patient had 2 follow-up studies. The MRI study always included T2-weighted fast spin echo and diffusion-weighted (DW-EPI) sequences. Single voxel proton spectroscopy (MRS) using STEAM technique (TE: 20 ms) was performed in 4 patients, 2 of them had both initial and follow-up studies, 2 others had follow-ups only. All patient were treated with dietary restrictions.

The initial MRI showed abnormalities on both T2 and DW-EPI images in 8 patients. At follow-up 2 patients had minimal, 2 moderate, 2 marked and 3 severe residual changes. The lesion pattern (involvement of the globi pallidi, diencephalic and posterior brainstem structures, and in the most severe cases the hemispheric white matter) was found to be rather characteristic. 3 patients had evidence of branched-chain amino acids (BCAA) on follow-up MRS, associated in 1 patient with severe, in another with marked and in the third, with moderate residual signal abnormalities. In the latter case, there was a decrease of the BCAA peak compared to the initial study.

In treated MSUD MRI typically shows improvement but therapy resistant cases exist and MRI abnormalities may remain prominent. MRS findings tend to correlate with the imaging evolution.

The We studied the possibilities of the positron emission tomography (PET) application for planning of SR by means of photon narrow beams in the treatment of SPD.

The study was aimed to develop a method for the preparation of patients with SPD for SR by means of positron emission tomography (PET). 17 PET-examinations were carried out in 7 patients with obsessive-compulsive syndrome resistant to medical therapy. Examinations were carried out using an original stereotaxic adapter. "Zero" position of the table for SR was taken as the initial coordinate points. Coordinates were marked by roentgenocontrast marks in the thickness of an individual fixing mask. Then the brain 18 FDG-PET (Ecat Exact 47) was carried out by a standard protocol in patients wearing an individual fixing mask in the head support. This was rigidly fixed to the tomograph table. Using the obtained PET-images, a calculation was performed of the patient displacements on three coordinate axes from markers to the selected brain structure-target. The calculated displacements, when the patient is laid on the accelerator therapeutical table in accordance with the "zero" coordinates, allow placement of the structure-target at the centre of the photon narrow beam dose field to within 1.5 mm.

The suggested method of patient preparation for SR by means of 18 FDG-PET using an original adapter does not require complex mathematical treatment. It provides a quick and precise matching of the aimed point the with ionizing radiation source isocentre, not only in the primary laying of the patient, but in repeated irradiation sessions.

Volumetry and T2 relaxometry of the amygdala complex in temporal lobe epilepsy P.M. Gonçalves Pereira 1 , M. Forjaz Secca 2 , A. Leal 2 , C. Ribeiro 2 , P. Evangelista 2 , A. Martins 2 , P. Rosado 2 , J.P. Cunha 3 ; 1 Porto/PT, 2 Lisbon/PT, 3 Aveiro/PT Purpose: In temporal lobe epilepsy the analysis of damage in extrahippocampal regions, such as the amygdalae, has received little attention. This study evaluates the occurrence of pathological values in the amygdala complex by means of quantitative MRI. Materials and methods: 25 age-matched controls and 27 patients with cryptogenic TLE were investigated using MRI based T1 volumetry and T2 relaxometry at 1.5 T. Image post-processing was performed manually. Ipsilateral and contralateral volumetry and relaxometry data were correlated with the side of the seizure focus for the whole amygdala. In order to further detail any independent contribution of the more ventral and dorsal amygdala areas, separate measures of the T2 decay were also correlated with the lateralization. Results were compared with control values using 99 % confidence ellipses. 

The comparison of single voxel proton magnetic resonance spectroscopy of the brain with long versus short echo time in the differential diagnosis of brain neoplasms W. Gajewicz, D. Jaskolski, B. Goraj; Lodz/PL Currently, in order to perform 1 H MRS with a SVS technique, long and/or short echo time sequences are used in order to provide complementary information.

Purpose: The aim of the study was to compare the usefulness of PRESS (TE 136 ms) and STEAM (TE 20 ms) sequences in the evaluation of brain neoplasms. Materials and methods: 10 healthy volunteers and 20 patients with brain tumors were examined using 1.5 T MR scanner. MRI was performed with a standard protocol for brain neoplasms. In tumor patients T1 weighted images obtained after intravenous administration of paramagnetic contrast medium were used as a localizer. 1 H MRS with the SVS technique was performed after MRI using PRESS136 and STEAM20 sequences (voxel size 1 to 8 cm 3 ). Results: Diagnostic spectra were obtained in all healthy volunteers and in 19 from 20 tumor patients. On the STEAM sequence, as well as basic metabolites visible in PRESS such as NAA, choline and creatine, peaks of myoinositol and Glx were visualized. In 5 cases data obtained with short TE sequences in conjunction with long TE data were necessary to identify the tumor type, and in one case this made in possible to establish the diagnosis of inflammatory changes with gliosis. These results were confirmed by pathology.

The use of short TE sequences enables visualization of metabolites important for the diagnosis and differentiation of the tumor types. The combined information drawn from both long and short TE spectra is also important. Problems appearing during acquisition and interpretation of short echo time spectra should not detract from these advantages.

MRI findings in six cases of multiple glioblastomas G. Mantzikopoulos, C. Pikoulas, G. Giannikouris, I. Staikidou, K. Glabedaki-Dagiada; Athens/GR Purpose: We present six cases of multiple cerebral glioblastomas and their MR features and key findings that can lead to the correct diagnosis. Material and methods: Six cases of glioblastoma multiforme, pathologically confirmed, were diagnosed in our department during the past 18 months. The ages of the patients, at the time of admission to our hospital, ranged from 60 to 74 years. Four of them were men and 2 were women. MR examinations included T1W spinecho images (before and after intravenous administration of gadolinium), T2W spin-echo images, FLAIR images, and T2W turbo spin-echo images. Results: In 3 cases MRI showed multifocal synchronous lesions, in 1 case MRI showed multicentric synchronous lesions, and in 2 cases MRI showed metachronous lesions, between two examinations. All lesions showed intense but non-uniform enhancement. Only in one case, a less than 0.5 cm lesion enhanced uniformly. Extensive oedema surrounded all lesions. Oedema from different foci merged, so that white matter between focal lesions had abnormal signal intensity. Conclusion: Multiple cerebral lesions in MR examinations may be interpreted as disease other than multiple gliomas, but careful attention to the pattern of intravenous contrast enhancement and peri-lesional oedema can suggest the correct diagnosis.

Cerebral After developing headache, the patient underwent a pre and post contrast enhanced CT brain scan, followed by MRI and MR Angiography studies. The imaging findings included arteriomegaly of both internal carotid and middle cerebral arteries and branches, as well as the posterior cerebral arteries, with fusiform aneurysms involving major cerebral vessels. These aneurysms place the affected children at risk for catastrophic stroke.

Early CT findings in acute middle cerebral artery ischemia M. Mohamed, R. Boguslawska, R. Poniatowska, G. Rejnowski, R. Krawczyk, T. Mendel, P. Kozlowski; Warsaw/PL Introduction: It has been stated in the literature that during the first hours after an acute ischemic attack (a.i.a.), CT usually shows no abnormalities. The aim of this study was to assess the reliability of the detection of early acute ischemic brain changes, the frequency of early CT signs of acute cerebral ischemia and to predict final infarct extension and topography.

CT studies of 50 patients admitted within 12 hours of onset of ictus and a follow-up study within 7 days were analyzed. CT was performed using 512 × 512 matrix, with 5 mm slices in the posterior fossa and an 8 mm slice thickness supratentorally. Results: On the first CT early signs of ischemia were a hyperdense middle cerebral artery (HMCAS), hypoattenuation of the lentiform nucleus (ALN), loss of insular ribbon (LIR) and hemispheric sulcar effacement (HSE). Early CT was abnormal in 90 % of cases, there was correlation between the incidence of early signs and the time of CT (P < 0.001 ALN, P < 0.33 LIR, P < 0.035 HSE, P < 0.011 HMCAS). At 3 hours the most frequent sign was effacement of cerebral sulci (45 %), ALN (18.2 %), LIR (27.3 %). At 9 hours percentages were: 100 % ALN, 100 % HSE, 85 % LIR. Presence of one, two or three signs was assocoated with massive MCA infarct (P < 0.001), ALN with deep MCA infarct (P < 0.0001), positive HMCAS correlated with massive MCA infarct (P < 0.001).

Use of contrast-enhanced MRI for detection of perfusion disorders in patients with cerebral atherosclerosis: Comparison with nuclear medicine imaging A.N. Koshman, S.K. Ternovoy, S.P. Pasha, N.N. Yachno; Moscow/RU Purpose: Aim of the study was to assess the usefulness of contrast MRI in the analysis of brain perfusion in patients with cerebral atherosclerosis and chronic ischemic lesions.

The study population consisted of 30 patients with cerebral atherosclerosis who had suffered an ischemic stroke 2 -6 month previously. All lesions had supratentorial location. Standard MRI, FLAIR, MRA and perfusion imaging (2D EPI sequence, 1 slice/second, 6 levels) were used. MRI was done using a Horizon 1.5 T imager (GE) with injection of Gd-DTPA-BMA. Perfusion maps were created for the analysis of images. Data obtained from MRI were compared with nuclear brain scintigraphy (NBS). Results: Perfusion MRI was able to show perfusion defects non related to chronic brain infarcts in 12 of 30 patients. Combined use of SE and FLAIR MRI together with perfusion MRI made it possible to differentiate viable hypoperfused areas from avascular ones. MRI data were in good correlation with NBS, but due to the higher spatial resolution MRI was superior for differentiation of the lesions. Conclusion: Combined use of different MRI modalities together with studies of brain perfusion with paramagnetic contrast agents allows the possibility of better detection of areas of decreased perfusion in patients with cerebral atherosclerosis.

Massive hydrocephalus in Gorlin-Goltz syndrome -late discovery I. Rozylo-Kalinowska, M. Jurkiewicz-Mazurek, K.T. Rozylo; Lublin/PL The Gorlin-Goltz syndrome (naevoid basal cell carcinoma syndrome) is a rare phacomatosis characterized mainly by disseminated basal cell naevi, multiple maxillary cysts (keratocysts), calcifications of the falx cerebri as well as numerous skeletal abnormalities. So far hydrocephalus has rarely been reported in the Gorlin-Goltz syndrome and has usually been described as mild. Frequently the syndrome is diagnosed in childhood.

We report a case of late discovery of Gorlin-Goltz syndrome in a mentally retarded 18-year-old woman referred for CT examination due to numerous maxillary and mandibular cysts detected on a Water's view X-ray. The cysts were well visualized on a panoramic radiogram as multiple radiolucencies, some of which had internal septa. The lesions were associated with several retained teeth. The performed coronal CT scans of the maxillofacial region verified the presence of cysts and accidentally revealed massive hydrocephalus as well as laminar calcifications of the falx cerebri. The findings were confirmed by cerebral CT scans. Other clinical features of the syndrome in the patient included hypertelorism, mild prognathism as well as palmar and plantar pits.

Detection and dynamic gadolinium-enhanced (CE) MR angiography. MIP and VR images were reconstructed for TOF-and CE-MRA data sets to investigate the presence of underlying aneurysms. For each detected aneurysm targeted MIP and VR images were performed to evaluate aneurysm morphologic features. Image quality and vascular delineation were also compared between MIP and VR images for detected aneurysms. Results: 23 of 24 aneurysms detected in 15 patients at DSA were depicted by at least by one MR angiographic technique with no false positive results. With volume rendering, the ROC analysis revealed an improved diagnostic confidence of intracranial MRA and increased aneurysm detectability (higher sensitivity and negative predictive value than MRA with MIP). Regarding aneurysmal morphology, VR performed better than MIP in lobulation detection and equally to MIP in neck categorization. The image quality obtained by VR was not rated significantly better than that obtained by MIP, however, the vascular delineation on VR images was found to be significantly better. Conclusion: Volume rendering technique facilitates the evaluation of cerebral MR angiography and enables more reliable detection and characterization of intracranial aneurysms than MIP.

Two Results: In SP patients NAA decreased 23 -25 % when compared with the RR group, Cr/Cho was changed in both groups. Concentration of Ins and lipids was significantly greater in the SP group than in the RR patients (50 -76 %). NAA/Cho + Cr was lower (48 -54 %) in the SP MS group. In debut MS patients, a reduction of Cho, Cr concentration and an increase of Ins concentration were recorded, NAA/Cho and NAA/Cr were more than 1 and reached 5.1 and 1.9 accordingly, which differed from other types of MS development.

Conclusions: 1 H NMR helps to evaluate the spread, character and intensity of the demyelinating process by Ins, NAA, Cr, Cho, Lipid concentration, and cerebral atrophy by NAA levels and NAA/Cr.

The predictive value of the early CT signs of acute middle cerebral artery infarction P.I. Argyropoulou, I. Manavis, H. Piperidou, I. Iliopoulos, S. Deftereos, P. Gkogkos; Alexandroupolis/GR Purpose: To estimate the predictive value of the early CT signs of acute (< 6 hours) middle cerebral artery (MCA) infarction, for subsequent infarct location, extension and hemorrhagic transformation (HT).

We studied prospectively 43 patients with a clinical presentation of acute MCA ischemia, with a duration < 6 hours. The patients underwent at least two CTs of the brain (on admission and on the 7 th day). The patients did not receive thrombolysis. On the first CT, we evaluated the presence of the hyperdense MCA sign (HMCAS) and early parenchymal signs (attenuation of lentiform nucleus, loss of insular ribbon, hemispheric sulcus effacement). The subsequent infarct location, extension and HT, were evaluated on the second CT. Results: The CTs on admission were performed at mean of 3 hours and 20 minutes. The first CT was abnormal in 40 patients (93.1 %). The HMCAS was found in 15 patients (34.8 %). The second CT performed in 41 patients (2 patients died in the intervening period). HT was found in 23 patients (56 %). The presense of two early parenchymal signs was significanly associated with an extended MCA infarct. The presence of loss of insular ribbon was associated with extended infarction. The presence of hemispheric sulcus effacement was associated with subsequent HT.

The early CT signs in acute MCA infarction, are useful predictors of subsequent infarct location, extension and hemorrhagic transformation.

Brain abscesses: Integration of neuroradiological diagnosis with antigranulocyte monoclonal antibody brain SPECT E.M. Covelli, E. Tedeschi, P. Sullo, C. Iaccarino, A. Improta, G. Mazzarella, G. Belfiore; Caserta/IT Purpose: To evaluate the usefulness of brain Single-Photon Computed Tomography (SPECT) with 99 Tc-labeled anti-granulocyte monovalent antibody fragments in aiding morphologic brain imaging (CT/MR) for the differential diagnosis of focal brain mass lesions.

In the past 6 months, 6 cases of brain abscesses were studied in our Diagnostic Imaging Dept. with contrast-enhanced CT and/or MR, and brain SPECT scans using FAB fragments of antigranulocyte monoclonal antibodies specific for the NCA-90 membrane antingen (LeukoScan) as a tracer. Age of the patients ranged from 1 month to 65 years, the responsible micro-organisms included Proteus and Streptococcus. Results: Brain SPECT acquired 1 hour after iv injection clearly displayed abnormal areas of high uptake at the level of the infectious lesions in all cases. In 2 patients with focal mass lesions of neoplastic origin (necrotic high grade glioma or metastasis) with somewhat similar CT/MR appearence, there was no uptake with SPECT.

Conclusions: 99 Tc LeukoScan brain SPECT, having shorter acquisition times and wider availability than conventional radioactive leucocyte scintigraphy, clearly shows the accumulation in mature brain abscesses, thereby aiding in the differential diagnosis of focal brain mass lesions.

Role of magnetic resonance angiography (MRA) in early surgical management of ruptured cerebral aneurysms: Experience in 75 patients A.M.A. Boerboom, T. Menovsky, H.L. Merx; Nijmegen/NL Introduction: Ruptured cerebral aneurysms can be detected on 3D MRA but its clinical value has not yet been proven. The objective of this study was to compare preoperatively anatomic information provided by MRA with the intra-operative results and DSA afterwards. Methods: In 36 months 75 patients with diagnosed subarachnoid hemorrage (CTscan or LP) had MRA (Siemens impact 1 T, 3D-TOF, TR/TE 37/9.6, flip angle 20) prior to surgery. The MRA were interpreted for the presence, location and direction of the aneurysm(s) and were compared with the intra-operative anatomy. In case of a negative or non conclusive MRA a DSA has been performed. After surgery a DSA was planned.

Results: In 58 out of 75 patients, one or more cerebral aneurysms could be detected on MRA (ppv = 100, confidence 94 -100 and npv = 76, confidence 50 -93). These patients where subsequently operated upon. In all these cases MRA correctly predicted the surgical anatomy and geometry of the aneurysm(s). In four cases there was a negative correlation between MRA and DSA. The remaining patients (n = 13), no cerebral aneurysm could be detected either by MRA or DSA and did not get operated upon. Conclusion: MRA in the clinical setting of acutely ruptured cerebral aneurysms is a safe and diagnostic tool for subsequent surgery. However, all negative MRA studies should be followed by DSA and caution is recommended when the precence of an aneurysm outside the field of view is suspected.

Myelinization patterns of white matter in infants, evaluated by FLAIR imaging Ö. Özsarlak, P.M. Parizel, J.W. van Goethem, A.M.A. de Schepper; Edegem/BE Purpose: Several pathologies may disturb the normal myelinization process in an infant as a first radiological sign. Therefore normal patterns of myelinization should be fully understood and recognized. Methods and materials: Premature to 2-years-old babies who underwent a brain-MR examination without any abnormality were grouped for each of 2 weeks of age. Sag SE T1, ax TSE T2, ax FLAIR sequences were routinely performed. The myelinization patterns of each group were defined with signal intensity changes. Results: We illustrate the myelinization pattern of each group. As defined in the literature, myelinization starts already during pregnancy. The first anatomical locations are brainstem, cerebellum, followed by internal capsule posterior limb, optic pathway, and parietal lobes. The best sequencies to show myelinization are TIR or FLAIR sequencies due to the greater water content of the infants brain and heavily T1 weighting effect. Conclusion: Myelinization starts during pregnancy and follows during the first year of life with a certain anatomical distribution. FLAIR images are most informative for the progress of cerebral white-mater myelinization.

Sexual differences in neural activation patterns observed during speech production task A. Urbanik, M. Binder, J. Kozub, B. Sobiecka; Krakow/PL Purpose: The aim of the study was the assessment of sexual differences in the strength and localization of neural activation patterns during speech production tasks, measured with functional magnetic resonance imaging. Methods and materials: 20 neurologically healthy, right-handed volunteers (12 women and 8 men) were examined in the Signa Horizon 1.5 T MR system (GEMS) using BOLD technique. Experimental design consisted of one activation run. It included two kinds of tasks -experimental and baseline condition -arranged in series of five blocks lasting for 30 s. In the experimental condition subjects were required to speak in their native language. During the baseline condition subjects were supposed to lie silently inside the bore. Acquired images were analyzed with SPM99 software (UCL, London). Results: All subjects revealed activation in regions associated with speech production located within perisylvian areas. We observed sexual differences associated with activation patterns, and they were associated with the strength and the extent of activation and not with localization of separate focal regions in subjects differing in sex.

Obtained results show that the strength and the extent of neural activation observed with fMRI can depend on subject's sex. Possible explanation is that the differences of neural organization and the resulting functional activation patterns are caused by the influence of sexual hormones on the development of nervous system.

Functional magnetic resonance imaging of human brain activity in dyslexics and normal volunteers A. Salagierska-Barwinska, A. Ciechomska, B. Goraj; Lodz/PL Objective: The advent of functional neuroimaging permits in vivo neuroanatomical investigation in humans, thus opening up many possibilities for determination which brain regions are implicated during word processing in dyslexics and normal volunteers. Although there have been substantial gains in the understanding of dyslexia, the neuropsychological and neurophysiological basis of this disorder is still not fully explained. Materials and methods: FMRI was carried out in 16 right-handed males (in 8 dyslexic participants and in 8 control participants). Our previous fMRI studies demonstrated gender effects on brain during a language task. All subjects were right handed as assessed by a standardized handedness test (were left-hemispheredominant for language). Three different cognitive language tasks were used: a verb generation language task, a semantic language activation task and a phonological language task. Statistical analysis of evoked blood oxygenation level-dependent responses, measured with echoplanar imagining (1.5 T), employed statistical parametric mapping (SPM). Results: Significant group differences were found for each of the three task conditions. The dyslexic men showed significantly lower activation compared with a control group in the left anterior quadrant of the brain during the same task.

Our study suggests that fMRI is a promising tool for the study of language organization in dyslexics and can be helpful in clinical diagnostic of this group of patients. 

The quantification of the transverse relaxation rate change under brain activation: Dependence on relaxation rate at rest and significance threshold E. Wiener, M. Settles, C. Ganter, E.J. Rummeny; Munich/DE Purpose: Published data of ∆R2* in BOLD imaging cover a wide range from about −0.1 to −3.0 s −1 . This becomes relevant when comparing quantitative values or when deducing related quantities like the CMRO2. Possible causes that influence ∆R2* can be given. Materials and methods: ∆R2* was measured in 37 subjects on a 1.5 T scanner (Philips, ACS-NT) performing a motor task using a segmented EPI double gradient echo sequence (TE = 23/70 ms) with five different voxel sizes between 1.8 and 41.7 mm 3 . An analysis of the errors involved in the calculation of ∆R2* and of the consequences of defining an arbitrary threshold of statistical significance in the data analysis was performed. Results: Scatter plots of −∆R2* versus R2* at rest for activated pixels exhibit the theoretically predicted correlation. A continuous increase of the average value of − ∆R2* with the threshold of significance and with decreasing voxel size are shown. Histograms of −∆R2* allow for a qualitative separation of false positives. At high spatial resolution (1.8 mm 3 ) the location of the activation peak seems to be quite insensitive to the choice of the threshold of significance. Conclusion: The standard method of selecting pixels of activation together with the marginal statistical significance of the BOLD-effect lead to two correlations: The change of the transverse relaxation rate depends on its value at rest via the statistical error. Averaged values are biased by selectively eliminating small signal changes when thresholding the test statistic. Histograms of activated pixels seem to be more reliable for estimating ∆R2*. FLAIR and enhanced T1WI, MTC and FLAIR images. The number, location and enhancement of lesions were examined by two experienced radiologists. Interobserver agreement was calculated. Results: In total, within the 44 patients, 754 plaques were demonstrated. 97.2 % of MS plaques showed hypointensity on T1WI. PD, T2W and FLAIR images revealed many more lesions than T1WI, all were hyperintense. FLAIR imaging allowed identification of 51 % more high signal lesions than PD/T2WI. In particular 65 % more cortical and subcortical lesions were identified. Infratentorially, PD/ T2WI demonstrated 17.8 % more lesions than FLAIR. There is a significant increase (21 %) in the number of detectable MS lesions on enchanced MTC images as compared with enchanced T1WI. No significant difference was found between unenhanced and enhanced FLAIR images. Conclusion: FLAIR images are very sensitive in demonstrating MS plaques. Infratentorially FLAIR images are less sensitive than PD/T2WI. Also enchanced MTC is very sensitive in revealing enhancing active plaques. Finally, enhanced FLAIR images are of limited value.

Stereotactic neurosurgical treatment of medically refractory Parkinson's disease: Proper patient selection, surgical technique, and pre-and postoperative radiologic evaluation A. Jeong; Seoul/KR Purpose: Stereotactic thalamotomy and pallidotomy are the two most common procedures designed to treat the symptoms of Parkinson's disease. Although thalamotomy is selected primarily to affect the tremor component of Parkinson's disease, pallidotomy has emerged as a procedure that addresses not only tremor, but also rigidity, bradykinesia, and dopamine-induced dyskinesia. The purpose of this exhibit was to review the proper patient selection, surgical procedure of each pallidotomy and thalamotomy as well as the clinical outcome and complications, in medically refractory Parkinson' disease Materials and methods: In our institution, 28 patients underwent pallidotomy (n = 15) or thalamotomy (n = 13). They had idiopathic Parkinson disease (n = 18), essential tremor (n = 3), dystonia (n = 2), Hallervorden Spatz disease (n = 1) and post-traumatic tremor (n = 1), post infarct tremor (n = 1), and post hemorrhagic thalamic pain (n = 1). Results: Successful stereotactic neurosurgery (thalamotomy or pallidotomy) was accomplished in most of the cases without significant complications. In almost all patients, their symptoms improved except in two cases. One had a partial response and the other had little effect. 3 of them had postoperative complications such as postoperative hemorrhage, dysarthria, homonymous hemianopsia. Conclusion: Stereotactic thalamotomy and pallidotomy are safe and promising procedures in medically refractory Parkinson's disease. It is important to be familiar with the pre-and postoperative radiologic evaluation in both pallidotomy and thalamotomy and to understand proper patient selection, the surgical procedures as well as the clinical outcomes and complications.

Fractional anisotropy and diffusion coefficient ‹D› in multiple sclerosis: Characterization of white matter structural damage F. Fasano, G. Hagberg, U. Sabatini, L. Fraracci, A. Castriota-Scanderbeg; Rome/IT Introduction: Change in hypointense lesion volume on T1-weighted MR images is recommended as a secondary outcome measure in definitive (phase III) clinical trials in multiple sclerosis (MS). Diffusion tensor imaging (DTI) provides information related to the tissue structure at a microscopic level. The aim of our investigation was to relate DTI-derived parameters to the appearance of MS lesions on T1weighted images. Materials: Twelve patients with MS and 12 sex and age matched healthy volunteers underwent a combined conventional and DTI MR protocol. Methods: For each lesion, FA and ‹D› mean values were derived from the DTI data set. Owing to regional heterogeneity of diffusion anisotropy in the normal brain, percentage FA variation in the lesions was computed, with reference to the symmetric normal appearing white matter (NAWM), the surrounding NAWM, and the corresponding normal white matter (NWM) in the matched normal subject (percentage FA variations 1, 2, 3). Results: The statistical analysis revealed overall significant group differences for ‹D› and FA. Percentage FA variation was highest in T1 markedly hypointense, intermediate in T1 hypointense, and lowest in T1 isointense lesions. Likewise, ‹D› was positively correlated with the degree of T1 hypointensity. Finally, absolute FA was lower in NAWM than in NWM.

Changes in FA and ‹D› suggest type-related structural differences in MS lesions, rather than variations due to anatomical brain architecture. Decreased FA in NAWM indicates the presence of diffuse microscopic alterations, invisible to conventional MRI. DTI parameters may provide significant insights into the understanding of structural changes associated with MS. We assessed the possibility of using TR-MRA instead of TTP in brain perfusion MRI (pMRI) for concomitantly evaluating stenotic changes of carotid artery. Materials and methods: The clinically symptomatic group (n = 7) and non-symptomatic group (n = 2) due to carotid occlusive disease underwent TR-MRA and pMRI with a 6 hour time-interval. TR-MRA (TR/TE 4.2/1.5 ms) was acquired in two sagittal slabs including cerebral hemisphere and carotid bifurcation at a rate of 3 frames/s. Subsequently, pMRI was performed with standard technique. Delay of signal intensity peak (SIP) of the TR-MRA in the ischemic attack area was compared with TTP mapping of pMRI. Carotid stenosis was graded as normal (0 %), mild (< 29 %), moderate (< 69 %), severe (< 99 %), occluded (100 %) on TR-MRA. Results: In the symptomatic group (n = 7), there were 2 incidences of occlusion, 3 severe, 1 moderate and 1 mild stenosis of carotid artery. However, 1 had mild and another had severe stenosis of carotid artery in non-symptomatic group (n = 2). The ranges of SIP delay (2 -6 s) on TR-MRA were prolonged corresponding with the grade of carotid stenosis in symptomatic group. However, non-symptomatic group showed no significant SIP delay on TR-MRA. The results of SIP on TR-MRA and TTP on pMRI were well correlated on Student t-test (p = 0.397). All of the patients showed good TR-MRA images for evaluation of carotid stenosis. Conclusion: Not only can SIP of TR-MRA replace the role of TTP on pMRI, but also carotid stenosis can be evaluated simultaneously on TR-MRA with single injection of contrast medium.

The role of two-dimensional magnetic resonance digital subtraction angiography (2D-MRDSA) in evaluation of intracranial abnormalities A. Uemura, T. O'uchi, T. Sakamoto, N. Yashiro; Kamogawa/JP Purpose: 2D-MRDSA is a new technique to demonstrate intracranial vasculature using rapid gradient-echo technique. The purpose of this study is to evaluate the clinical usefulness of 2D-MRDSA in intracranial abnormalities. Materials and methods: 30 cases (12 brain tumors, 10 cerebrovascular occlusive cases, 4 cerebral infarctions, 1 cerebral hematoma and 3 normal cases) are included in this study. 2D-MRDSA was studied with SIEMENS VISION 1.5 T MR unit (SIEMENS, Germany) using 2D turbo-FLASH. Each image was obtained at about 1 second continuously just after injection of gadolinium-DTPA up to 30 seconds in sagittal, coronal and axial planes. We evaluated hemodynamic information, visualization of the intracranial vasculature and the tumor blush in arterial phase in comparison with those of 3D time-of-flight (TOF) MRA and conventional DSA. Results: In all 30 cases, pure arterial, capillary and venous phases are clearly obtained. Major arterial trunks and dural sinuses were also well identified. However distal arterial branches were not well visualized in 20 cases, whereas on 3D-TOF-MRA and conventional DSA they were well visualized in all cases. The tumor blush in the arterial phase was well demonstrated in 7 cases of 12 brain tumor cases and correlated with those on conventional DSA. In 9 of 10 cerebrovascular occlusive cases, the occlusion site is well identified. Conclusion: 2D-MRDSA has a satisfactory temporal resolution and an ability to demonstrate cerebral hemodynamics, neovascularity of the tumor and cerebrovascular occlusion. However the clinical applicability is limited due to the low spatial resolution.

Cortical dysplasia in childhood epilepsy -clinical, imaging and drugtherapy correlates J. Hat, L. Cvitanovic, B. Mucic, M. Kalousek, D. Bedek, N. Besenski; Zagreb/HR Purpose: The aim of the study was to compare psychomotor development, EEG and epilepsy with location of cortical dysplasia (CD) and seizure control.

Material and methods: Six children aged 1 to 8 years. In 4 patients seizures occurred during a febrile illness between 8 and 18 months. No seizure attacks were seen in 1 girl with hemiplegia and 1 girl with delayed psychomotor development. Clinical examination, EEG, CT and MRI of the brain was performed. Results: In all six children CT scan of the brain showed focal cortical atrophy and dysplastic changes. MRI of the brain identified focal CD: in 3 children on one and in 1 case, on both temporal lobes (2 had also schizencephaly), in 1 child on parietal lobe and in 1 on the frontoparietal region. The follow-up of patients is 1 -8 years. In 1 girl good seizure control was obtained with valproate and for the last 5 years she has been without antiepileptic drugs (AED). Two children had a good seizure control with AEDs for the last 8 years. Partial efficacy was obtained in 1 boy. Two children with EEG and morphological changes are without seizures and have not received AED. The usefulness of three-dimensional CT-angiography (3D-CTA) in detection of remnant necks was compared with intraarterial DSA (IADSA) in patients who had undergone clipping surgery for cerebral aneurysms. Materials and methods: Eighteen patients (24 aneurysms) underwent both IADSA and 3D-CTA following clipping surgery for cerebral aneurysms. 3D-CTA was performed with a spiral scanner. Parameters were 1 mm/s table speed and 1 mm collimation. Three-dimensional CT reformations were obtained by using the shaded surface display (SSD) algorithms. Two neuroradiologists independently evaluated the existence of remnant necks on both 3D-CTA and IADSA. Evaluation on 3D-CTA was blindly separated from that on IADSA. The results jointly evaluated by three observers were applied as the gold standard to assess the sensitivity and specificity of IADSA and 3D-CTA. Results: The sensitivity and specificity of 3D-CTA in detection of remnant necks were 83.4 % and 90.0 %, respectively. On IADSA, the sensitivity and specificity were 100 % and 92.9 %, respectively. Interobserver correlation was better in IADSA than in 3D-CTA. On 3D-CTA one observer overlooked one remnant neck (false negative). Although two observers pointed out remnant necks of four aneurysms on IADSA, they pointed out remnant necks of three aneurysms on 3D-CTA. In one aneurysm, the tip of clip was mistaken as a remnant neck on IADSA (false positive), however 3D-CTA clearly could show the relationship between clip and the adjacent arteries. Conclusion: In patients following clipping surgery for cerebral aneurysms, 3D-CTA can detect remnant necks almost equally compared with IADSA. 3D-CTA can depict the relationship between clips and the adjacent arteries.

Preliminary assessment of proton single-voxel MR spectroscopy for neuroepithelial brain tumor classification W. Szeszkowski, M. Golebiowski; Warsaw/PL Purpose: Our goal was to assess the utility of proton single-voxel MR spectroscopy in the clinical diagnosis of various types and grades of neuroepithelial brain tumors Materials and methods: 29 patients with intraoperative biopsy-confirmed neuroepithelial tumors were examined. The subjects were divided into four groups based upon the malignancy of the tumor subtypes (Kernohan classification). Eleven cases were classified as grade I, six grade II, six grade III, and six grade IV. A control group consisted of 15 healthy volunteers. The studies were conducted using a 1.5 T MR unit, equipped with a head-coil and an advanced spectroscopy package. Single-voxel spectra were acquired using the point-resolved spectroscopic pulse sequence (PRESS) with parameters of 136/2000 ms (TE/TR). Results: The metabolites of interest were lactate at 1.3 ppm, NAA at 2.0 ppm, creatine at 3.0 ppm, and choline at 3.2 ppm. Metabolic peak areas were normalized to the area of the creatine peak. Nonparametric analysis of variance (ANOVA) tests showed statistically significant differences among the various tumor types for all the area ratios (see table below). Both the choline and lactate levels could be used to separate the high-grade (IV) from the medium-grade (II/III), and medium-grade (II/III) from the low-grade tumors. Lactate level appeared to be an especially good marker to discriminate all four groups (grade I, II, III, IV) of brain tumors. Conclusions: Specific relative metabolic peak area ratios acquired from regions of contrast-enhancing brain tumor can be used to classify neuroepithelial tumors as to histopathologic grade.

Various MR features of dysembryoplastic neuroepithelial tumor Y.H. Jeon; Seoul/KR Purpose: The purpose of this study was to describe the various MR features of dysembryoplastic neuropithelial tumor (DNET). Materials and methods: 20 patients (eleven male and nine female, aged 7 -51 years) with pathologically proven DNETs were included in this study. We retrospectively analyzed the location, configuration, pattern of growth, involvement of deep white matter, signal intensity and multiplicity of cystic lesion on MR images. Results: DNETs were located in the temporal lobe (n = 17), frontal lobe (n = 2), and occipital lobe (n = 1). Most tumors were intracortical or subcortical. The configurations of tumors were gyriform (n = 13) (65 %), nodular (n = 3), and mixed type (n = 4). An exophytic pattern of growth was seen in 4 (20 %) cases. Involvement of deep white matter by the tumor was found in 4 (20 %) cases. On T1weighted images, the signal intensities of cystic lesion were isointense to CSF in 6 cases (30 %) and hyperintense than CSF in 8 cases (40 % Results: Κ value for agreement was 0.34. In patients with agreement on negative residue (n = 16), echogenic rim with less than 5 mm thickness, distinction from surrounding tissues and nodules were detected in 81.2 %, 93.7 % and 18.2 %, respectively. However, in three cases (2 glial tumors and one metastasis with extensive peritumoral edema) whom magnetic resonance images showed residue despite a negative sonography, the same findings were present in all, all and one third of the patients, respectively. Surgicel, which impairs sound transmission, was detected in two thirds of the patients in this group. Conclusion: An echogenic rim of less than 5 mm with clear distinction from surrounding tissues and nodules does not preclude the absence of residue, and cavity borders must be biopsied when necessary. The main difficulty in detecting residual tumor with intraoperative ultrasound images is presence of extensive edema and surgicel. For all patients, the signals from N-acetylaspartate (NAA), choline-containing compounds (Cho), creatine-phosphocreatine (Cr) and myoinositol (mI) were compared with 32 healthy volunteers as metabolites ratios and metabolites areas to non-suppressed water area ratios. Results: A significant increase in Cho/Cr (p < 0.001) and mI/Cr (p < 0.01) ratios in HIV patients were found. The NAA/Cho ratio was significantly lower (p < 0.01), but there was no changes in NAA/Cr ratio. A statistically significant reduction in NAA/H20 and Cr/H20 (both p < 0.05) and increase in mI/H20 (p < 0.05) ratio were observed. As for the immune status there was statistically significant correlation (r = 0.47, p < 0.05) between CD4 counts and NAA/H20 ratio.

These results indicate that neuronal loss and gliosis in HIV-infected patients may be associated with impairment of energy metabolism. The spectral changes found in the present study suggest that 1 H MR spectroscopy can be used for early detection of brain damage induced by HIV. Purpose: Many conventional MR sequences are used to characterize the content of cystic intracranial lesions. We evaluated retrospectively the role of diffusionweighted imaging to differentiate between intracranial cysts with free water-like content versus those filled with a non-free water-like substance. Materials/methods: 67 cystic intracranial lesions were studied using T1-weighted, proton density (PD)-weighted, T2-weighted and, fluid-attenuated inversion recovery (FLAIR) sequences. Diffusion-weighted images were obtained in the transverse plane using a multislice single-shot SE echoplanar pulse sequence with a b-value of 1000 s/mm 2 . The diffusion gradients were applied along three directions (x, y, z) simultaneously. The results were compared with true content as evaluated either histologically or on the basis of clinical, neuroradiologic, and follow-up features. Results: On diffusion-weighted imaging arachnoid cysts (n = 15), porencephalia (n = 3), pineal cyst (n = 1) and schizencephaly (n = 1) had similar signal intensity with CSF. Brain abscess (n = 2), epidermoid cysts (n = 3) and dermoid cyst (n = 1) showed high intensity compared to brain parenchyma. The content of cystic astrocytomas (n = 3), glioblastomas (n = 6) and metastasis (n = 6) was markedly hypointense on diffusion-weighted images compared with normal brain parenchyma in all patients. In three cases with cystic metastasis and three cases with glioblastoma multiforme, the necrotic portion of tumors was heterogeneus hypo-and hyperintense on diffusion-weighted images due to hemorhagic content which was verified with gradient echo images and CT. Discussion/conclusion: Diffusion-weighted imaging depicts accurately the content of cystic intracranial lesions and is valuble in distinguishing between neoplastic, inflamatory or maldevelopmental lesions when used in addition to conventional MR sequences.

Long-term angiographic follow-up in young patients with successfully treated aneurysmal subarachnoid hemorrhage J. Rinne, A. Ronkainen, R.L. Vanninen, T. Saari, J. Hernesniemi, M. Vapalahti; Kuopio/FI Purpose: Younger patients with even successfully treated aneurysmal SAH might carry a higher risk for new aneurysm formation and new bleeding. We conducted a pilot study on young patients with ruptured aneurysms treated in our unit during 1977 -1990 . Methods: The selection criteria were: patients who were < 35 years at the onset of SAH, who made good recovery and who were younger than the peak incidence age for SAH at the time of follow-up. Method for follow-up was four-vessel digital subtraction angiography. Both the initial and follow-up studies were read by a neurosurgeon and a neuroradiologist. 

Cerebral blood flow and cerebral autoregulation: Simultaneous measurement of arterial and venous cerebral blood flow in MRI for the detection of asynchroneous changes during the Valsalva maneuver A. Kluge 1 , E. Stolz 2 , M. Kaps 2 , G.F. Bachmann 1 ; 1 Bad Nauheim/DE, 2 Gießen/DE Purpose: To develop and evaluate a method for simultaneous arterial and venous measurement of cerebral blood flow (CBF) in MRI for the examination of changes during the respiratory cycle, especially during the valsalva maneuver.

The total arterial and venous cerebral blood flow was simultaneously registered using flash 2D phase-contrast (PC-MRI) flow quantification sequence in 12 healthy volunteers. ECG-gating and 9-fold segmentation resulted in 4 to 7 phases per ECG-cycle, a temporal resolution of 2.6 to 3.7 s was achieved. The flow was measured through plane at the skull base. Changes during the respiratory cycle, during the valsalva-maneuver and during sudden blood pressure drop (leg-cuff) were examined. Results: The examination was feasible in all 12 subjects, reproducibility for flow quantification was 3 %. The temporal resolution of 2.6 to 3.7 s showed to be sufficient to detect changes in the arterial and venous blood flow during the respiratory cycle and to demonstrate resulting changes in net CBF. Especially during the valsalva-maneuver, the cerebral autoregulation showed a delay in adaptation of the blood flow resulting in an initial increase in cerebral blood volume. Conclusion: Simultaneous arterial and venous PC-MRI blood flow measurement showed to be a highly reproducible and exact tool for the examination of the total cerebral blood flow. Asynchronous adaptation of arterial and venous flow could be demonstrated. Advantages over doppler ultrasound are higher reproducibility, higher robustness of quantitative results and the possibility to evaluate the complete CBF. This will allow an improved insight into cerebral blood flow autoregulation.

The use of proton magnetic resonance spectroscopic imaging (CSI) in creating the metabolite maps of the brain and evaluation of brain neoplasms W. Gajewicz, W. Papierz, M. Zawirski, B. Goraj; Lodz/PL Progress in 1 H MRS enables collection of spectroscopic data using single voxel spectroscopy (SVS) and chemical shift or spectroscopic imaging (CSI, MRSI). Purpose: The aim of the study was to present the possibilities of using 1 H MRS with CSI techniques in performing metabolite maps and in the evaluation of brain neoplasms. Materials and methods: 10 healthy volunteers and 21 patients with brain tumors were examined using 1.5 T MR scanner. MRI was performed with a standard protocol for brain neoplasms. In tumor patients T1 weighted images obtained after intravenous administration of a paramagnetic contrast medium were used as a localizer. 1 H MRS was performed using CSI SE135 and SVS STEAM20 sequences. The obtained data were analysed as single spectra for consecutive voxels, metabolite maps and spectral maps. Results: In normals it was possible to determine metabolite contents within brain white and gray matter in multiple volumes of interest simultaneously. In tumor patients spectroscopic image based on concentrations of a chosen metabolite enabled to visualize the tumors' heterogeneity. Analysis of the spectra from multiple voxels combined with short TE spectra allowed identification of the tumor type confirmed later by pathology in 16 cases. Conclusions: 1 H MRSI proved to be a useful tool in the evaluation of brain tumors because: most of the tumor tissue can be covered by multiple voxels, tumor heterogeneity can be assessed, measurements are less biased by the pre-selection of the volume(s) of interest by the operator. Movement artifacts connected with long acquisition time can be the limitation.

Fetal cerebral ventriculomegaly A. Ozanne, N. Girard, C. Gire, C. D'Ercole, C. Chau, V. Millet, C. Raybaud, M. Panuel; Marseille/FR Purpose: To describe the MR imaging of fetal cerebral ventriculomegaly, which represents 38 % of indications of fetal cerebral imaging. To also determine whether the ventriculomegaly was isolated or associated with brain abnormalities. Material and methods: We report 320 cases of ventriculomegaly described on fetal cerebral MR imaging. The MR examinations were indicated following ultrasonographic, clinical and biological datas. We studied the developmental outcome; when the ventriculomegaly was isolated we compared the signification of several features of the ventriculomegaly as the size of atrial diameter, as the unilaterality. Results: The cause was malformative in 30 % of cases, destructive in 26 %, and isolated in 36 %. When explored with US, the ventriculomegaly was isolated in 85 %. The outcome was better when ventriculomegaly was mild (upper limit at 15 mm) and when unilateral. Conclusion: Fetal cerebral MR imaging can more precisely characterize than US whether a ventriculomegaly is isolated or not. Looking at the outcome of isolated mild ventriculomegaly, it is currently difficult to define on MR imaging benign criteria.

Preoperatory evaluation of intracranial aneurysms during subarachnoid hemorrage with multidetector helical CT angiography G. Vaudano, R. Boccaletti, M. Sandrone, G. Stura, C. Cametti; Turin/IT Purpose: To evaluate if Multidetector Helical CT Angiography (MHCTA) can replace Digital Substraction Angiography (DSA) for detection symtomatic (bleeding) intracranial aneurysms and if it is possible to map out a neurosurgical strategy in patients with subarachnoid hemorrage (SAH). Materials and methods: 45 patients with SAH underwent MHCT Angiography; 25 also underwent DSA. Radiologists and Neurosurgeons discussed each case for presurgical evaluation using imaging of MHCTA with Maximum Intensity Projection (MIP) and Volume Rendering (VR). All the cases were operated upon. Results: 44 (98 %) symptomatic aneurysms were observed with MHCTA and 53 altogether (9 patients had twin aneurysms), of variable size from 2.5 to 21 mm; 25 (100 %) symtomatic aneurysms were discovered with DSA and 27 altogether (2 patients had twin aneurysms), identifying also the aneurysm not seen with MHCTA. The Neurosurgeons assessed MHCTA adequate or superior to DSA in 84 % of 45 symptomatic aneurysms, in 20 cases (44 %) neurosurgical strategy has only been based on MHCTA.

Conclusion: MHCTA can identify the bleeding aneurysms (98 %) during SAH and allow planning of neurosurgical strategy using MHCTA with MIP and VR.

Diffusion and perfusion-weighted MR findings in a 38 weeks pregnant woman with hypertensive encephalopathy C. Micheli 1 , M. Muti 2 , M. Caulo 3 , P. Baldi 1 , M. Gallucci 3 ; 1 Rieti/IT, 2 Terni/IT, 3 L'Aquila/IT Purpose: Vasogenic edema in hypertensive encephalopathy has been demonstrated using diffusion weighted MR; in this case "vasogenic theory" has been validated by the addition of MR perfusion imaging. Materials and method: A 17 years old women at the 38 th weak of gestation was admitted because of a 3 hours onset of headache, vomiting, blindness and left hemiplegia. Conventional MRI, perfusion and diffusion-weighted imaging were performed at admission and on follow-up after 10 days. Using a 1.5 T MR unit T2weighted MR imaging and isotropic DW imaging were performed by using diffusion gradients in three orthogonal directions and ADC maps were generated from DW images; T2* EPI sequences and automatic injection of contrast material (3 ml/s) were employed for perfusion MR study. Maps of rCBF and MTT were obtained in a post-processing stage. Results: Conventional MRI at admission revealed bilateral occipito-parietal high intense areas on T2-w sequences; the ROI positioned on the hyperintense regions revealed an increase of the rCBF in both the subcortical white matter (4 times) and in the cortex (2 times) when compared with the corresponding contralateral spared regions; a 40 % decrease of the MTT was also detected in the ROI. ADC was increased in the involved white matter (1.4 × 10 −3 mm 2 /s). MTT and rCBF resulted normal at the 10 days MR follow-up. Conclusions: Our data may confirm the postulated vasodilatatory origin of the vasogenic edema occurring during reversible hypertensive enchephalopathy. In the light of these data the vaso-spastic theory should be considered less likely. Purpose: Detailed comparision of MRI and histopathology of injured spinal cords has allowed a deeper understanding of the nature of such injuries in both the acute and chronic stages. In this exhibit, we present a simple grid to classify spinal injuries and describe typical spinal ligamentous injuries. Materials and methods: This exhibit is divided into three sections. The first describes the injuries to the craniocervical junction, the second reviews the remainder of the spine, and the third addresses the technical factors that optimize the detection of the injuries. We based our MR classification system upon the pathomorphological characteristics of the injuries. All MR images were performed on a 1.5 T MR unit (Siemens Symphony, Erlangen). Results: All types of injuries could be classified according to our suggested system (Type A, B, C). Conclusion: Our suggested MRI classification system is comprehensive and injuries can be iterized according to easily recognizable and consistend MRI and clinical findings. In our clinical experience, MRI has been an invaluable adjunctive technique, in particular in patients with relevant neurologic deficits.

Improved diagnostic method for intervertebral foramen stenoses H.A. Musalatov, A.G. Aganesov, V.I. Telpuhov, A.D. Chensky, M.T. Sampiev, I.V. Shahabov, L.F. Pestereva, K.S. Ternovoy; Moscow/RU Purpose: To raise the diagnostic accuracy of intervertebral foramen stenoses that can lead to severe back or leg pain. Methods and materials: 10 patients with low back pain and sciatica underwent X-ray examination, we proceeded to use the Siemens "Magnetom Harmony" 1.0 T for examination. Sagittal and transverse projections were used for general visualization of the spine. Selective oblique projections were applied for evaluation of intervertebral foramen. We used the transverse projection to evaluate the angles of the oblique slices. Then, with the help of the console we measured the specimen squares of foramen as well as the area of the nerve root. By taking measurements of both areas, we were then able to calculate the "reserve space index" using our new approach. We then compared our results to ones based on X-ray evaluation of two coefficients and we found the X-ray based ones to be accurate to 30 %. Results: In total, 100 intervertebral foramens were examined, using both methods. In cases where the "reserve space index" was found to be less then 1.22, we diagnosed stenosis of intervertebral foramen. Summary: The combination of the MRI's multiplanar ability and digital console obviously offers an accuracy in measurement that is perfectly suited to carry out the complex calculations required to accurately find the "reserve space index". The ability of MRI to exam soft tissue brings much needed depth in the search for the reasons of low back pain and sciatica. With an average of 4.2 months after beginning of therapy a d-MRI-follow-up examination in 9 of these patients was performed. The amplitude and exchangerate-constant were calculated and a statistical comparison of these values between healthy persons and MDS patients as well as a correlation with the clinical course was executed.

Results: Compared with the normal controls the MDS patients showed a higher amplitude (normal persons: 14.4 ± 5.2, MDS: 24.8 ± 8.1) and exchange-rate-constant (normal persons: 0.124 ± 0.042, MDS: 0.136 ± 0.036). Concerning the amplitude values this difference was highly significant (p < 0.001). In 7 of 9 MDS patients undergoing a thalidomide therapy a reduction of the amplitude and exchange rate constant values was evident in the d-MRI-follow-up examinations. Clinically these patients showed a therapy responding with complete or partial diseases remission. Conclusions: In MDS patients significantly higher d-MRI-parameters can be demonstrated than in normal persons. Under anti-angiogenetic treatment these values decrease in the case of a response to therapy. Thus, d-MRI seems suitable for the evaluation of anti-angiogenetic therapy effects.

Spontaneous intracranial hypotension associated with a sacral arachnoid cyst M. Gil-Garcia, C. Vicandi, R. Begue, J. Díez; Lerida/ES Spontaneous intracranial hypotension is a rare but well known entity. The course of the disease is benign but the underlying cause is rarely established. Spinal cerebrospinal fluid leak is often implicated as the cause but it rarely can be demonstrated radiographically or surgically. We present a case of a thirteen year old woman who developed spontaneous intracranial hypotension after a minor trauma over sacrococcygeal region. Magnetic resonance images of the lumbar spine demonstrated an intrasacral arachnoid cyst and free fluid at the presacral space. With conservative medical treatment, complete clinical remission was observed. A month later magnetic resonance images of the lumbar spine showed a complete resolution of the leakage of CSF at the presacral space. Purpose: Chiari III malformation is a rare abnormality, which is characterized by the herniation of posterior fossa contents (cerebellum, and sometimes brainstem and fourth ventricle) and/or upper cervical spinal contents through a low occipital and/or upper cervical osseous defect. We present our experience in different presentations of Chiari III malformations. Methods and materials: Three patients (all males with an age interval of 2 -16 months old) with swellings at the back of the craniocervical area and hydrocephalus were referred to our MRI unit. Cerebral MRI studies in each patient was performed with SE T1, FSE T2, and FLAIR sequences in three planes on a 1.5 T MR scanner.

The patients revealed small posterior fossa volume, low lying transverse sinuses, he hypoplastic tentorium cerebelli, creeping of the cerebellar hemispheres around brain stem, elongated and tube-like narrowed fourth ventricle, dysgenesis of corpus callosum, triventricular hydrocephalus, and colpocephaly. One patient had concave clivus and petrous bone, two patients had tectal beeking, two patients had syringomyelia. Two patients revealed herniation of cerebellovermian formations through an occipital-upper cervical osseous defect. One patient revealed herniation of medulla oblongata and upper cervical spinal cord initially through foramen magnum, then dorsally through a cervical spina bifida. Conclusion: Since the initial report of Chiari, the definition of Chiari III malformation has been expanded to include the cases of hindbrain and upper cervical spinal cord herniations into low occipital and/or high cervical meningomyeloencephaloceles. We presented diversity of imaging findings in Chiari III malformation in this study.

Neurological manifestations of aspergillosis: Overview A. Guermazi 1 , E. de Kerviler 2 , A.-M. Zagdanski 2 , S. Kacimi 2 , B. Tabti 2 , J. Frija 2 ; 1 San Francisco, CA/US, 2 Paris/FR Purpose: To review the clinical and radiologic features of aspergillosis affecting the central nervous system (CNS) in patients who had undergone bone marrow transplantation. Methods and materials: 50 proven cases of CNS aspergillosis have been retrospectively studied. Results: Cerebral aspergillosis is being seen with an increased frequency due to the increased numbers of immunosuppressed patients, particularly those who have undergone bone marrow transplantation. In most cases, aspergillosis develops in the paranasal sinuses and in the lungs, and secondarily spreads to the brain. Imaging of cerebral aspergillosis may present different patterns depending on the lesion's age and the immunologic status of the patient. Spinal cord lesion are for less common but has been encountered in our series. Conclusion: Significant morbidity and mortality can be associated with this fungal infection, and it is therefore incumbent upon the radiologist to identify intracranial aspergillosis as early as possible so that appropriate therapy can be administrated. A review of CNS aspergillosis infection with different CT and MR patterns will be presented, including pertinent clinical and pathologic material.

MR study of patients with neurofibromatosis type 2 (NF2) and their families R. Poniatowska, A. Koziarski, R. Krawczyk, R. Boguslawska, P. Kozlowski; Warsaw/PL Introduction: Neurofibromatosis type 2 (NF2) is an autosomal dominant disease with the abnormality located on chromosome 22 and appears in 1 in 50000 of the population. The diagnostic criteria consist of bilateral VIII schwannomas or a unilateral VIII schwannoma with two from the group: neurofibroma or schwannoma in other location, meningiomas, glioma and a relative with NF2. Purpose: Of the study was to detect pathological changes in patients with NF2 and their relatives using MR imaging.

The study population consisted of 17 patients with NF2 and 55 members of their families who underwent clinical, audiometric and neuroradiological studies. MR studies were performed using SE sequences, with T1-, PD-and T2-weighted images, in sagittal, axial and coronal planes. After contrast injection the study was repeated using SE T1-weighted sequences. Results: MR studies had shown in all patients with NF2 VIII schwannomas, in 2 cases V schwannoma, in 13 patients cranial meningiomas, in 2 intraventricular tumors, in 4 intramedullary tumors, in 8 spinal schwannomas in 1 spinal meningioma. In 4 members of NF2 patient's families small acoustic schwannomas, meningiomas, T2-weighted hyperintensive foci (gliosis) and calcification were detected. Conclusion: We conclude that early detection of pathology in patients with NF2 and their relatives allows the course of the disease to be followed and early surgical treatment to be performed where necessary.

Radio-anatomy and pathology of the hearing pathways E. Menif, H. Ben Romdhane, K. Nouira, W. Douira, R. Slim; Tunis/TN Introduction: Hearing involves the participation of a peripheral system, from the external ear until the ponto-cerebellar angle and a central system which involves the pathways and centers of hearing. The purpose of this work is to define the anatomical entities of hearing and to correlate these to clinical findings and to determine a strategy for imaging investigation (CT and MRI) of deafness. Material and methods: A retrospective study of 800 consecutive patients over a 5 year period was performed. 450 patients were investigated for a perception deafness, 300 normal temporal bones in patients having a pathology of the contralateral ear were included. There were 35 cases of malformation of the ear and 15 voluntary patients. 335 high resolution CTs of the temporal bone as well as 470 MRIs were performed. The CT was performed in millimeter thickness axial and coronal scans every 0.5 mm with multiplanar reconstructions. The MRI contained a standardized protocol with an axial SE T2 sequence of the brain, a CISS 3D sequence, SE T1 fine axial scans pre and post contrast; additional sequences, notably of the anatomical pathways, were perfomed. Results: Detailed radio-anatomy was obtained. According to the clinical findings (deafness of transmission, perception or mixed) and associated neurological signs, a correlation between the found pathology and the anatomical affected site was possible. Conclusion: A good anatomical knowledge and of the physiology of the hearing allows the choice of the most appropriate imaging technique.

High resolution ultrasonography of peripheral nerve branches at the upper and lower extremities P. Kovacs, G. Bodner, H. Gruber, S. Peer, W.R. Jaschke; Innsbruck/AT Purpose: To demonstrate the feasibility of depicting peripheral nerve branches in both the upper and the lower extremities of cadavers using high resolution ultrasonography (US). Methods and materials: In both upper and both lower extremities of a 90 year-old cadaveric specimen branches of the major motor and sensory nerves were detected by means of a 5 -12 MHz broad band linear transducer in transverse planes. After assessing each peripheral nerve, on one side US-guided injection of blue ink (0.2 ml) in the nerve-sheath was performed. Corresponding ultrasonographic planes were cryosected (3 mm, fine needle band saw) to compare US and cryosectional findings side by side. Results: At the upper limbs the musculocutaneous, median, ulnar and radial nerve, including superficial and deep branches, were detected and correctly marked by means of US. Also at the lower limbs the femoral, sciatic, tibial and common fibular nerve with their superficial and deep branches were detected by US and correctly marked. Conclusions: Knowing the topography of the peripheral nerve branches of the upper and lower extremities, high resolution US allows dectection of all major nerves with their superficial and deep branches.

Moyamoya disease: Radiological features and accompanying disorders A.C. Durak, M. Ozturk, A. Coskun; Kayseri/TR Purpose: The study of the radiological features and the accompanying disorders in patients diagnosed as having moyamoya disease. Methods and materials: The radiological findings of 4 patients (2 male and 2 female; age range 3 to 26 years, mean age 17.2 years) were evaluated. Findings from MRI and MR angiography in all the cases, DSA in two cases and CT and plain radiography in one case are presented. Results: There was bilateral internal carotid artery involvement in two cases, bilateral carotid and distal basilar artery disease in one case and unilateral carotid artery involvement in one case. In the first patient there were marked bilateral ischemic-atrophic variations and extensive collateral filling from the posterior circulation. This case was characterized by severe growth retardation was clinically followed up with the diagnosis of Seckel syndrome. In the second patient there were similar vascular changes, cardiac anomalies, diffuse calvarial thickening. Ischemic foci and hemorrhage were detected in the cerebral MR images of the third patient with internal carotid and basilar involvement. Collateralization was observed in the M1 and A1 segment localizations in the last patient with the involvement of the right carotid. Conclusion: In Moyamoya, a great many accompanying disorders have been described. In this presentation we have reviewed Moyamoya disease, presenting two cases accompanied by calvarial thickening with cardiac anomalies and Seckel syndrome.

Three 4) To present different pathologies related to this anatomical area. Material and methods: 50 consecutive 3D-CISS sequences were performed in patients who were referred for evaluation of labyrinth lesions and neurogenic syndromes related to cranial nerves V -XI. A 1.5 T MR unit was used. 3D labyrinthine anatomy volume rendering (3DVR), maximum intensity projections (MIP), and multiplanar reconstruction (MPR) of CPC were acquired. Results: Cranial nerves, internal auditory canal, cochlea, semicircular canals, vestibulum, vascular structures were visualised in detail. Pathology referred to each one of these elements was found and explained. The involved pathology of these elements covers cranial nerves (neurinoma, agenesis, meningioma); labyrinth (occlusion, pre-post operative assessment, fistula); vascular involvement (loops, malformations, neurovascular compression) and cerebellopontine cistern (different kinds of masses). Conclusion: The 3D-CISS MR imaging, volume rendering, MIP and MPR evaluation proceedings provide an excellent way for both diagnosis an exclusion of pathology related to the labyrinth, CPC and its contents.

MRI quantitative study of cerebrospinal fluid in patients with hydrocephalus W. Yao, X. Chen, T. Shen, M. Li; Shanghai/CN Purpose: To study cerebrospinal fluid (CSF) flow in patients with hydrocephalus with MRI cine PC. Materials and methods: On the basis of the experiment result, CSF flow at the level of aqueduct, foramen magnum and C2 was examined in 19 cases with obstructive hydrocephalus and 16 cases with communicating hydrocephalus. The flow velocity and magnitude of CSF at aqueduct and foramen magnum were also examined post operatively in 10 of 16 communicating hydrocephalus. Results: In the aqueduct of patients with communicating hydrocephalus flow velocity and quantity were much higher than that of normal volunteers, the outflow and inflow peak velocity were 47.57 ± 16.71 mm/s and 44.48 ± 19.22 mm/s respectively, and the quantities of outflow and inflow were 3.142 ± 1.055 ml/s and 3.143 ± 1.055 ml/s respectively. At foramen magnum outflow and inflow peak velocity were 1.37 ± 0.44 mm/s and 1.33 ± 0.41 mm/s, the quantities of outflow and inflow were 0.351 ± 0.125 ml/s and 0.350 ± 0.121 ml/s respectively. At C2 outflow and inflow peak velocity were 2.41 ± 1.27 mm/s and 2.95 ± 1.15 mm/s respectively, and the quantities of outflow and inflow were 0.521 ± 0.214 ml/s and 0.519 ± 0.214 ml/s. No obvious CSF flow was found at the site of obstruction in the patients with obstructive hydrocephalus. In 10 patients with communicating hydrocephalus, CSF flow velocity and quantities in the aqueduct were decreased significantly (P < 0.05). Conclusion: MRI cine PC is a noninvasive method for studying CSF flow direction, flow velocity and flow quantity accurately. MRI cine PC has the capability to predict whether the symptoms of communicating hydrocephalus will be relieved.

Neural correlates of working memory activity during performance of verbal and nonverbal tasks A. Urbanik, M. Binder, B. Sobiecka, J. Kozub; Krakow/PL Purpose: Working memory is considered to be a cognitive system responsible for the temporary storage and manipulation of different kinds of information. The aim of the study was the attempt to answer the question whether there are specialized brain structures that support working memory functions associated with performance of verbal and non-verbal tasks. Materials and methods: Twelve neurologically healthy, right-handed volunteers were examined in the Signa Horizon 1.5 T MR system (GEMS) using BOLD technique. Experimental design consisted of two activation runs. Each of them included different task. During the first run subjects were required to remember the changing sequences of letters, and during the second run they were asked to remember changing sequences of abstract pictures. Statistical analyses were carried out using SPM99 software. Results: For both verbal and nonverbal task, localization of the several active areas partially overlapped, and the common activated areas were situated in the prefrontal cortex: dorsal-lateral prefrontal cortex bilaterally, ventral-lateral prefrontal cortex in the left hemisphere and the anterior cingulate gyrus. Furthermore, there were separate activation sites for the nonverbal and verbal tasks, which were observed in the left parietal cortex for the verbal task and the frontal cortex for the nonverbal task. Conclusion: In our study we observed separate areas responsible for different aspects of working memory performance, namely, manipulation (update and monitoring) and storage of information. Regions responsible for manipulation were independent of the task, and localization of regions responsible for storage was associated with the type of stimulus (verbal or nonverbal).

MR findings in oculomotor nerve palsy J.C. Paniagua, S. De la Mano, A. Framiñan, J. Arganda; Salamanca/ES Purpose: To assess the utility of MR in third cranial nerve palsy. Methods: We reviewed precontrast and postcontrast MR of 68 patients with third cranial nerve palsy. Results: MR demonstrated an appropriate lesion in 30 cases. Of these patients, 7 had brain stem lesions and 16 had involvement of the nerve in the cavernous sinus; lesions of the cisternal segment of the nerve were present in 9 patients. An inflammatory or infiltrative source of palsy was indicated in 12 of these 30 cases. 38 patients with a history of diabetes or vascular disease had normal MR findings. Conclusions: Patients who do not have a history of diabetes or hypertension and in whom a complete or incomplete third cranial nerve palsy develops should undergo MR imaging initially (unless there are clear symptoms of subarachnoid hemorrhage) to exclude the presence of an infiltrative lesion or intraparenchymal process. Patients who have a history of vascular disease and a clinical presentation that is suggestive of an ischemic event may be observed initially, but should undergo imaging if improvement does not occur within 3 months.

Neurofibromatoses (NF1 and NF2): Pictorial review of CT and MRI manifestations in multiorgan disease A.P. Koureas, A.D. Gouliamos, E.C. Panourgias, A. Moulopoulos, S.J. Trakadas, L.J. Vlahos; Athens/GR Purpose: The objective of this exhibit is to describe and illustrate the wide spectrum of imaging findings in this condition with the aid of CT and MRI. Methods and materials: We retrospectively reviewed the imaging findings of CT and MRI studies performed at our institution in selected patients with neurofibromatosis 1 and 2. This entity comprises a group of diseases of two main types and many atypical forms. The typical forms are autosomally dominant inherited, even though half are new mutations. More than one million people are affected. Specific features of this entity include characteristic tumors, benign, malignant or with malignant potential. Results: With the advent of MRI and its multiplanar capabilities, the value and importance of imaging in the diagnosis of neurofibromatosis has increased. The diagnostic criteria for this entity in children and in adults are described, as well as the role of imaging in patients with known disease and screening of relatives. The imaging findings which help distinguish benign and malignant features, as well as malignant degeneration are reviewed. Furthermore, the atypical manifestations of this disease are discussed. seems to be the best diagnostic tool because of the lack of radiation exposure and the possibility of multiplanar imaging. It is the optimal method for follow-up investigations after tumour resection. Case report: A 9 year old girl with prolonged dysphagia, demonstrated a narrowing of the distal oesophagus with proximal dilatation on barium study. This was suspected to be oesophageal leiomyomatosis and she underwent MRI (1.5 T Magnetom Vision, Siemens). MRI was performed using breathhold FSE T2weighted imaging, gradient echo T1-weighted imaging with and without fat saturation. Additionally breathhold T2-weighted multiplanar HASTE imaging was performed. All sequences demonstrated a homogeneous tumour of the lower oesophagus extending to the gastric fundus with extensive wall thickening up to 3 cm and lumen reduction. Moderate homogeneous contrast enhancement of the tumour was shown. The girl's 14-year-old brother and the children's mother presented with the same symptoms. In all three cases histopathological analysis after surgery revealed leiomyomatosis. The two children also had sensorineural deafness and renal lesions such as glomerulonephritis. Postoperative MRI confirmed complete tumour resection and normal findings at the cervical oesophageal-gastric anastomosis.

Acute appendicitis: Should US be performed if the clinical presentation is highly suggestive of the disease? G. Roic, Z. Milic; Zagreb/HR Introduction: The diagnosis of appendicitis based on clinical and laboratory results can be non-specific; atypical clinical presentations may result in diagnostic confusion and delay in treatment. Purpose: The aim of this study was to evaluate the role of US in the diagnostic work-up of children with acute right lower quadrant disease and to compare US findings with the clinical diagnosis of this disorder. Method and materials: 303 paediatric patients (2 -14 years) with clinical presentations suspicious of appendicitis were evaluated with ultrasonography. According to clinical presentation patients were categorized into low, moderate and high-risk groups. Results: 22 % of the 303 patients had proven appendicitis. 53 % of children in the high clinical risk group for appendicitis, 15 % in the moderate risk group and 9 % in the low risk group had appendicitis. Treatment plans were changed after US examination in 44 % of the patients in the high-risk group, 38 % patients in the intermediate risk group, and 34 % in the low risk group. The US suggested an alternative diagnosis in 33 % of the patients. Discussion: Mesenteric adenitis is one of the more common appendicitis mimicking disorders and cause of acute abdominal pain in children. The etiologic agent is unknown, but Y. enterocolitica has been implicated in some cases. Yersinia, Campylobacter and Salmonella are the most common causative agents of acute terminal ileitis. Although intussusception has typical clinical features, it may mimic appendicitis. Conclusions: We believe it is necessary to perform US in every child with acute abdominal pain, even if the clinical diagnosis seems well established.

US study of the hip in children: Normal anatomy F. Esposito, D. Noviello, M. Valentino; Naples/IT Purpose: To study the normal US patterns of the anterior joint capsule of the hip. Materials and methods: 38 asymptomatic children (21 M, 17 F) between 2 and 7 years of age, without a history of hip disease were examined. The US examinations were performed with a 7.5 MHz transducer in the supine position with the hip in a neutral position. An anterior approach along the long axis of the femoral neck was used to visualize the anterior capsule of the hip joint. The anterior joint capsule was identified, and the thickness of the capsule was assessed by measuring the maximal distance between the anterior surface of the femoral neck and the posterior surface of the iliopsoas muscle including visualization of the shape of the anterior profile. Results: The anterior joint capsule was easily identified in all the children. In 22 of 38 (57.8 %) children examined it was possible to identify both the anterior and posterior layers that compose the capsule. In 20 of 38 (52.6 %) patients a linear reflection representing the interface between both layers could be distinguished. In all patients the shape of the anterior profile was concave. However, the contour of the joint capsule depends on rotation, being concave in external rotation and convex in internal rotation. The mean thickness of the anterior joint capsule was 4.2 ± 0.4 mm. Conclusions: Ultrasound is a non-invasive technique, not employing ionizing radiation, allowing accurate visualization of the pediatric hip. Knowledge of the US anatomy is essential for diagnosis and follow up of hip pathologies.

Unusual cystic abdominal masses in children M. Andreu, C. Duran, J. Branera, V. Medina, C. Martín, P. Melloni; Sabadell/ES Objective: To show the radiological features of unusual abdominal cystic lesions in the paediatric age group. Material and methods: We retrospectively reviewed 11 cases of unusual cystic abdominal lesions, seen in the last 10 years, in a 71000 population of less than 15 years of age. The patients were imaged by abdominal plain film (n = 11), ultrasonography (n = 11), computed tomography (n = 6) and magnetic resonance (n = 4). Clinical manifestations included vomiting, a palpable abdominal mass with or without abdominal pain and prenatal abdominal cystic lesion detection.

The final diagnosis of cystic lesions were: hepatic foregut cyst (n = 1), hepatic hydatid cyst (n = 1), duplication enteric cyst (n = 1), mesenteric cyst or giant cystic lymphangioma (n = 1), urachal cysts (n = 2), cystic teratoma in a subphrenic location (n = 1), intrauterine ovarian torsion that evolved spontaneously into calcification after birth (n = 2) and congenital epidermoid cysts (n = 2). Abdominal radiographs showed mass effect in all 11 patients. The ultrasound appearance was: purely cystic (n = 3) or a complex cyst (n = 8). The CT appearance was variable with a complex pattern in the majority of the cases: presence of cystic areas with peripheral calcifications, hyperdense linear structures and septae and one case with a solid intracystic nodule. MR demonstrated the contents of the lesion in one case. Conclusion: Because of the low incidence of this kind of abdominal pathology in children, awareness of the aspects and indications of the different imaging methods can be useful in their diagnosis.

Pleural empyema: A sonographic study in the pediatric age group and its value in assisting treatment M.I. Martínez-León, J. Martos-Forniels, L. Ceres-Ruiz, I. Alonso-Usabiaga, E. Vals-Moreno, D. Moreno, A. Salvá-Veyn; Málaga/ES Introduction: To prove the correlation between a sonographic heterogeneous pattern, with or without septa, and the evolution of pleural complications that need prompt treatment with fibrinolysis to be effective. A specific sonographic pattern indicates more active and early treatment to avoid more agressive treatments and minimize hospital stay. Material and methods: Our population consisted of 27 paediatric patients with proven empyema diagnosed and treated in our Paediatric Referral Centre between January 1998 and August 2001. Results: All had chest radiographs and ultrasound in the 1 st -3 rd day in hospital; 16 had sonographic follow up. Thoracic CT was performed in 21 patients. Bacterial growth was demonstrated in only 7 patients (5 S. pneumoniae, 3 S. aureus, 2 H. influenzae, 2 Mycoplasma, 1 S. viridans). Initial ultrasound showed 54 % had a heterogeneous pattern with septae, 30 % heterogeneous without septae, 13 % anechoic and 3 % homogeneously echogenic. Pleural thickening was foud initially in 55 % of cases. Sonographic follow up showed radiological improvement in 65 %, persistence of the pattern in 20 % and 15 % deteriorated. 63 % were treated with fibrinolysis, using Urokinase, 90 % of these patients improved at sonographic follow up. 29 % had thoracoscopy and 8 % had thoracotomy. Hospitalisation was 15.5 days in empyemas treated with fibrinolysis and 25 days with videothorascopy and thoracotomy. Conclusions: We recommend immediate treatment with urokinase in patients with a heterogeneous sonographic pattern with septae in the clinical context of infectious pleura disease. If this is implemented within the first week more agressive treatments are prevented and the length of hospital stay is reduced.

Reduction of unnecessary skull radiographs in children with head trauma -a repeat audit following change K. Johnson, S. Williams, M. Balogum; Birmingham/GB An audit was performed at the Birmingham Children's Hospital to assess the compliance of requests for skull radiographs (SXR) with Royal College of Radiologists guidelines. Despite a compliance of 85 %, only 7 % of SXRs following head trauma demonstrated a fracture, implying that unnecessary SXRs were being performed. With the implementation of the new UK Ionising Radiation regulations in January 2001, there is increased responsibility on the radiologist to justify the use of ionising radiation. A multidisciplinary team of relevant departments developed a modified local protocol for SXRs with more stringent indications. Additionally an educational programme for medical staff was initiated. This audit aimed to determine current compliance with the modified guidelines and to assess whether the rate of negative SXRs had been reduced without compromising patient care.

All children with a head injury in defined 3 month period were followed up. The clinical indications for any SXR performed (n = 95) was recorded. A compliance of 95 % with the new SXR guidelines was achieved. A 30 % reduction in the number of skull radiographs from the emergency department was achieved, despite increased numbers of children attending with head trauma. 10.5 % of radiographs demonstrated a fracture. No child has had a missed diagnosis at follow up. There has been no increase in the number head CTs performed. The implementation and monitoring of defined protocols for SXRs will reduce the number of unnecessary examinations performed. Emphasis on adhering to local protocols and training junior staff is essential.

The contribution of MR imaging in foetal gastrointestinal malformations X. Durbise, C. Aube, F. Thouveny, B. Delorme, C. Duverne, D. Loisel, C. Caron-Poitreau; Angers/FR Purpose: To study the use of MR imaging in 3 cases of foetal gastrointestinal malformation and a review of the literature. Method and materials: Three foetuses with gastrointestinal tract malformations discovered on obstetric ultrasonography underwent MR imaging on a 1.5 T Signa Imager with T1 SPGR and SSFSE sequences. MR imaging was retrospectively reviewed and compared with post natal imaging and surgical results. Results: Post natal imaging and surgery confirmed all three MR diagnoses. In the first case MR images showed incomplete duodenal obstruction (duodenal dilatation, hyperintense T2 small bowel downstream, hyperintense T1 large bowel, and a normally placed caecum). An upper gastrointestinal contrast study and surgery confirmed incomplete duodenal stenosis. In the second case, MR showed terminal small bowel distention (hyper T1 and hypo T2 dilated loop with fluid level). Contrast enema showed a microcolon and small bowel distension, surgery found jejunoileal atresia. In the third case, MR showed proximal small bowel dilatation (anterior to the stomach with no high T2 signal downstream). An upper GI contrast study confirmed the proximal small bowel obstruction. Surgery found an "apple peel" type small bowel atresia. Conclusion: Foetal gastrointestinal malformations are a difficult ultrasound diagnosis. Distinguishing amniotic liquid from meconium, MR imaging should permit accurate evaluation of the topography of foetal gastrointestinal abnomalities of small or large bowel, and so permit appropriate surgical care in such rare and serious pathologies.

Chronic abdominal pain in children: A review of 500 ultrasound examinations M.K. Sapundzieski, Z. Taseski, R. Aceska, V. Vasileska; Prilep/MK Introduction: A large number of ultrasound examinations are performed in children for chronic abdominal pain. We present a review of our findings during a one year period, identifying the benefit and outcome of these findings. Materials and methods: We selected 500 children, aged 0 -10 years, examined in the year 2000. In all of them we performed an ultrasound examination of the abdomen and urinary tract, in both a supine and prone position, using Aloca Duna View equipment with multifrequency probes. The two main indications were chronic abdominal pain and chronic urinary tract infection. Examinations for acute conditions and other causes were excluded. Results: 275 patients were referred for chronic abdominal pain: 89 % of them had a normal ultrasound examination. Only 11 % had pathological findings, mostly due to urinary problems. 225 patients were referred with chronic urinary tract infection: 56 % had a normal ultrasound and 44 % had pathological findings. Among these, most were uncomplicated urinary infections with a thickened bladder wall and just a few had signs of complicated infection such as an pelvi-calyceal dilatation. Conclusion: Ultrasound examination of the abdomen and urinary tract is a fast, safe and cheap investigation. In cases with urinary tract infection the benefit and outcome from the examination was little higher than in cases with chronic abdominal pain.

HRCT evaluation of small airways involvement in cystic fibrosis K.M. Unsinn, M.C. Freund, J. Eder, H. Ellemunter, W.R. Jaschke; Innsbruck/AT Purpose: The HRCT scoring system proposed by Bhalla and co-workers evaluates mainly large airway abnormalities in cystic fibrosis, e.g. severity and extent of bronchiectasis, as well as extent of peribronchial wall thickening and mucous plugging, but not small airways disease. However the small airways represent an im-portant functional subunit and involvement in cystic fibrosis is not easily assessed by various lung function parameters. The purpose of the study was to evaluate the involvement of small airways in cystic fibrosis by HRCT. Methods and materials: In total 158 HRCT exams were performed in 80 patients aged 4 months -44 years (mean age 16.3 years) and retrospectively evaluated for the presence of advanced small airways disease i.e. tree-in-bud structures and centrilobular nodules (representing abnormal peripheral bronchioles filled with mucus or pus and displayed in the cross-sectional or longitudinal plane) combined with a > 50 % involvement of the peripheral secondary lobules in a subpleural location. Results: In total 64 HRCT exams (40.5 %) of 20 patients (25 %) demonstrated the typical morphological involvement of small airways disease in older children. Additionally the HRCT-findings i.e. tree-in-bud structures and centrilobular nodules, will be explained utilizing HRCT-pathologic correlation from selected clinical examples. Conclusion: Involvement of small airways disease is more often detected than formerly presumed in other reported studies; this underscores the inclusion of the described morphologic parameter into a cystic fibrosis CT scoring system.

The contribution of MR imaging in foetal genitourinary malformations B. Delorme, C. Aube, F. Thouveny, D. Loisel, X. Durbise, C. Duverne, C. Caron-Poitreau; Angers/FR Purpose: To evaluate the contribution of MR imaging in foetal genitourinary malformations. Methods and materials: Eight foetuses with urinary tract abnomalities, discovered on obstetric ultrasonography underwent MR imaging on an 1.5 T Signa Imager with SSFSE sequences imaged in the three standard planes. MR imaging was retrospectively reviewed and compared with post-natal imaging. Four foetuses presented with multicystic dysplastic kidney with a megaureter and 3 of these also had a ureterocele. Two foetuses presented with a complete duplication one with a ureterocele and one without. The two remaining foetuses presented with an isolated megaureter and a sub capsular urinoma respectively. Results: SSFSE T2 MR imaging always permits a good analysis of the kidneys, intrarenal collecting system, dilated urinary tracts, bladder and pelvis, particularly in the sagittal and coronal planes. MR gives at least morphological complementary information in all cases. It changed the previous diagnosis in four cases. Conclusion: Foetal MR imaging is an interesting complementary morphological study in complex genitourinary malformations. In some difficult ultrasonographic cases, this accurate morphological analysis permitted correction of an initially wrong diagnosis.

Ultrasonographic evaluation of chest diseases in children M.T. Raissaki, A. Bakandaki, E. Mihailidou, I. Papantoniou, E. Mantzouranis, N. Gourtsoyiannis; Iraklion/GR Purpose: To appreciate the role of ultrasound (US) in the evaluation of chest diseases in children.

The study comprised 32 children aged 3 months to 16 years (mean age 3 years) that underwent 40 ultrasound scans of the thorax. Indications for US in 23 children were an abnormal chest radiograph, 3 with total lung opacification, 6 with a bulging of the thoracic wall and in 3 clarification of findings identified with CT or MR. The thoracic wall, the surface of the lungs and the mediastinum were scanned with linear or convex arrays 3.5 -8 MHz, depending on the indication. Results: Ultrasound identified pleural lesions in 12 children, intrapulmonary lesions in 18, thoracic wall lesions in 6 and mediastinal lesions in 6. US characterized non-specific findings in 19 children, prompted further imaging in 8 and verified known abnormalities in 5 cases. Therapy was modified according to the US findings in 6 children with lower respiratory tract infection. Conclusion: US may be employed as a significant initial or complementary imaging modality for the evaluation of chest diseases in children. Material and methods: Nine children suspected of having biliary disease were evaluated by ultrasonography. Effort was made to visualise the whole length of the common duct to the level of the papilla and the pancreatic region. This was followed by CPRM and ERCP was then performed. Results: Five children had choledochal cysts, one with a common pancreatobiliary channel. Cholelithiasis was found in three, debris in the biliary duct in one, choledocholithiasis in three, and a dilated common duct with cholangitis in two and pancreatitis in two. Discussion: Determining whether a dilated choledochal system on imaging is due to choledocholithiasis, a choledochal cyst or related to an anomalous pancreatobiliary duct union is an important issue since surgical treatment will vary from performing papillary excision to a Roux en Y hepatic-jejunostomy respectively. Ultrasonography is the most useful initial method of evaluating the biliary system, showing high correlation with cholangiography and CPRM. It is very important to differentiate between a choledochal cyst and dilated common duct due to choledocholithiasis and to look for pancreatobiliary duct union because they all require different surgical treatment. Therefore, we must complement ultrasonography with cholangiography and CPRM, removing the complications of ERCP in children. 

During a recent 1-year period, in four children aged 9, 12, 15 and 16 with clinically suspected renovascular hypertension, DSA was performed. In three children a renal artery stenosis between 80 and 90 % due to fibromuscular dysplasia was discovered, in two of them unilateral and in one bilateral. In one child, a long stenosis of unknown etiology was detected. In all the patients, PTRA was performed after having defined exactly the morphology and hemodynamics of the renal artery stenosis. Results: In three children we achieved very good results. PTRA was successful resulting in an improved arterial luminal diameter. PTRA was unsuccessful and repeated in one child with severe stenosis and had emphasized "recoil" phenomenon. Autotransplantation was then performed. Conclusion: PTRA is the method of choice and a first line therapy in the treatment of renovascular arterial hypertension.

Fetal MRI in vein of Galen malformation: Are there predictors of neonatal outcome? A.M. Fink; Melbourne/AU Purpose: Vein of Galen malformation (VGAM) is associated with a spectrum of postnatal morbidity, including neonatal demise. Antenatal MRI allows early confirmation of the diagnosis, with view to parental counselling. Findings likely to predict outcome are discussed. Materials and methods: MRIs of two fetuses were reviewed, and correlated with postnatal clinical and MRI findings. Results: In the first, visualization of multiple enlarged feeding vessels reflected a choroidal type of VGAM, which usually presents with neonatal cardiac failure, vascular steal phenomena, and a high incidence of mortality (as in our case). Dilatation of the straight sinus and jugular veins, and enlargement of the ventricles was also observed. In the second, non visualization of feeding vessels at 26 weeks reflected a mural type of VGAM, which is low flow and not associated with neonatal problems. In our case it resulted in regression of the VGAM, seen on follow up fetal MRI at 36 weeks, and postnatal MRI. There was no other intracranial abnormality. The cerebral parenchyma was normal in both. Conclusion: These cases illustrate that fetal brain MRI in suspected cases of VGAM can confirm the diagnosis, and help predict the outcome at birth, not only by assessment of anatomical brain changes, but also by predicting the risk of neonatal cardiac failure and vascular steal. Visualization of enlarged feeding vessels suggests a choroidal type VGAM with high flow and poor outcome. When these are not visualized, the neonatal outcome is likely to be good, including possible spontaneous intrauterine resolution of the malformation.

Intracranial meningiomas in chidren: Review of five cases S.A. Im; Puchoen/KR Purpose: To present the radiological and histopathologic findings in five children with meningioma. Materials and methods: We reviewed CT and MRI of five children aged 19 years or less with pathologically proven meningioma. Results: The age range was 9 to 19 years (mean: 14.2 years). There were 4 girls and 1 boy. One child had associated neurofibromatosis. The pathologic subtypes were transitional (n = 1), fibroblastic (n = 1), psammomatous (n = 1), angioblastic (n = 1), malignant (n = 1). Compared to the adult counterpart, childhood meningiomas showed atypical features: cysts, hemorrhage, severe oedema, and unusual location. Diagnosis of the extra-axial tumour was relatively difficult in two of the patients with meningiomas, one malignant meningioma and one angioblastic meningioma. Conclusion: Awareness of the atypical histopatholgic subtype, location, and radiological features of childhood meningiomas may be helpful in differentiation from other brain tumors.

Three-dimensional ultrasound (3DUS) in the pediatric urinary tractpreliminary experiences M. Riccabona, G.A. Fritz, G. Bohdal, E. Ring; Graz/AT Purpose: To report our preliminary experiences with 3DUS of the pediatric urinary tract. Methods and materials: 60 pediatric patients underwent 3DUS of the bladder and/or the kidneys after conventional US had been performed. 3DUS was performed with either a Voluson 530/730 (Kretztechnik/GE, Austria/USA) or an external 3D-system (Echotech/GE, Germany/USA) attached to conventional transducers. 3DUS focused on validation of renal volume assessment, demonstration of hydronephrosis, and potential applications of virtual cystoscopy. 3DUS results were compared with standard imaging where available/indicated (2DUS, scintigraphy, MRT, CT, cystoscopy). Results: (1) In 55/60 patients at least one 3DUS acquisition of the bladder/kidney was of diagnostic quality; no sedation was used for 3DUS. (2) 3DUS offered a better demonstration of the dilated collecting system in hydronephrosis and/or megaureter than 2DUS. (3) 3DUS of the bladder enables virtual cystoscopy at yet a reduced resolution, capable of demonstrating gross pathology. (4) 3DUS volume measurements were accurate compared to CT/MRT (± 5 %) in undilated kidneys. 2DUS volume estimates are less accurate (> ±10 %) in kidneys with dilated collecting systems or scars indicating that 3DUS offers more accurate volume measurements particularily in irregularly shaped structures. There was a good correlation of relative renal volume on 3DUS compared to split renal size on scintigraphy in patients free of acute renal parenchymal disease. Conclusion: 3DUS promises to be a valuable adjunct to 2DUS in evaluating pediatric urological disease. However prospective studies are necessary to evaluate the indications and diagnostic value of the individual condition.

Gadolinium-enhanced three-dimensional MR angiography in the assessment of thoracoabdominal aortic pathologies: Pediatric applications S. Fitoz, Ç. Atasoy, I. Erden, S. Akyar; Ankara/TR Purpose: To investigate the role of gadolinium-enhanced magnetic resonance angiography (MRA) in the evaluation of pediatric thoracoabdominal aorta pathologies. Materials and methods: 21 patients aged 1 day to 14 years with known or suspected thoracoabdominal aorta pathologies were included in the study. MR imaging was performed with head or torso coils on a 1 T scanner. After having obtained axial, oblique sagittal and/or oblique coronal T1-weighted images, gadolinium-enhanced MRA was performed with 3D spoiled gradient echo pulse sequence (TR/ TE, 4.8 -6.3/1 -1.9 ms, flip angle 20 -30°). Scan delay was selected empirically or calculated after a test dose. MR and MRA findings were compared with the results of Doppler ultrasonography, digital subtraction angiography, computed tomography and surgery. Results: Gadolinium-enhanced 3D MRA successfully showed both the normal and abnormal vasculature, which included coarctation of the aorta in 12, vascular abnormality in 5, and pulmonary sequestration in 4 patients. The location and extent of the coarctated segment, aortic arch hypoplasia and restenoses were successfully displayed in patients with coarctation of the aorta. MRA demonstrated the aberrant artery in 4 patients with sequestration, while the draining veins were depicted in 3 of the patients.

Conclusion: Gadolinium-enhanced 3D MRA, either breath-hold or non-breathhold, allows rapid and noninvasive imaging of the pediatric thoracoabdominal aorta lesions. Although the venous system becomes opacified early in small children with rapid hemodynamic status, this does not preclude assessment of the arterial system owing to the use of MIP reconstruction and multi-angle viewing.

MR urography compared to conventional intravenous urography in pediatric patients S. Hirohashi, A. Ohkura, S. Kitano, T. Taoka, M. Koh, R. Hirohashi, K. Kichikawa, H. Ohishi; Nara/JP Purpose: The purpose of this study was to establish the utility of MR urography (MRU) compared to intravenous urography (IVU). Method/materials: 30 children with urological abnormalities under 12 years of age that had undergone MRU and IVU were enrolled in this study. Five studies were for the initial diagnosis and 27 studies for follow-up. The median duration of the MRU and IVU was 1 month in the initial diagnosis and 12 months in the follow-up studies. We used a 1.0 T MR machine and a single shot fast spin echo sequence for MRU. At first, the two blinded radiologists tried to diagnose by only reading the MRU, and then determined the diagnostic efficacy of MRU in comparison with IVU by reading them simultaneously. Results: Of 5 patients, the correct initial diagnosis by MRU was reached in 4 patients except for one patient with a non-dilated pelvicalyceal system and ureter. The diagnostic efficacy of MRU was evaluated as superior in 3, equal in 1, and inferior in 1 to that of IVU. Of 27 patients having follow-up studies, the correct diagnosis by MRU was reached in all patients. The diagnostic efficacy of MRU was evaluated as superior in 11, equal in 15, and inferior in 1 to that of IVU. Conclusions: MR urography has several advantages for pediatric patients in comparison with intravenous urography, it is suggested that the technique should be applied instead of intravenous urography especially for follow-up studies.

A paracardial lipoma with rapid enlargement in a 8 year old girl A. Trusen, M. Beissert, W. Kenn, K. Ergezinger, D. Hahn; Würzburg/DE We present the case of an 8 year-old girl with gross obesity. A chest radiograph was initiated by a pulmonary infection and a paracardial mass was diagnosed. On ultrasound a 4 cm diameter solid mass was detected. Further investigation showed a hyperintense mass on MRI consistent with fatty tissue and the diagnosis of a lipoma was made. There were no signs of malignancy. 4 weeks later a follow-up X-ray was performed due to recurrent pulmonary infection and rapid enlargement of the paracardial mass was noted. On ultrasound as well as on MRI growth of the mass was confirmed. Meanwhile the patients weight had increased by 3 kg. Due to the enlargement surgery was indicated. Intraoperatively a 6 × 6 cm large tumour was excised. Histologically the diagnosis of a paracardial lipoma was confirmed. Discussion: Mediastinal lipomas in children are rare. The differential diagnosis includes malignant liposarcomas or, in children under 3 years, benign lipoblastomas must be considered. According to the literature, in children, mediastinal lipomas like retroperitoneal lipomas should be surgically excised. Whether the enlargement of the lipoma in our patient was due to the general weight increase could not be assessed.

Three dimensional reconstructions and virtual bronchoscopy of multislice helical CT data in children N. Furukawa, H. Nishihara, A. Araki, D. Urabe; Kurume/JP Purpose: To investigate the utility of computed tomographic (CT) three dimensional reconstructions (3D) and virtual broncoscopy (VB) in evaluating tracheobronchial pathology in the pediatric population. Materials and methods: 20 patients (12 male, 8 female. Mean age was 3 years 2 months, range 3 months to 9 years) suspected or known to have tracheobronchial pathology including a tracheal or bronchial foreign body, compression or narrowing of the tracheobronchial tree due to various causes, tracheomalacia, and branching anomalies, were reviewed. All patients underwent multislice helical CT (MSHCT). The data were transferred to a workstation to obtain 3D and VB images. Results: Generation of 3D and VB images was possible in all patients. At least the fourth-generation bronchi could be visualized and evaluated on both 3D and VB images. Both 3D and VB images provided similar information to fibreoptic bronchoscopy or bronchography in investigating these tracheobronchial pathologies, and provide exquisute and sufficient images for diagnosis. The underside of a stenotic lesion could be depicted by VB while fiberoptic bronchoscopy could not visualise it. Conclusion: Although employing radiation, CT virtual bronchoscopy is a promising noninvasive technique for use in the investigation of various tracheobronchial pathologies. Exquisite 3D and VB images obtained from MSHCT data may become an alternative imaging technique to invasive fiberoptic bronchoscopy or bronchography in the future.

Use of gadobenate dimeglumine for the evaluation of post-traumatic biliary accumulation: Clinical relevance L. Grazioli 1 , M. Bondioni 1 , G. Morana 2 , M.A. Kirchin 3 , S. Crespi 1 , M. Menni 1 ; 1 Brescia/IT, 2 Verona/IT, 3 Milan/IT Purpose: To evaluate the use of gadobenate dimeglumine (Gd-BOPTA; a contrast agent with partial hepatobiliary excretion) for the visualisation and definition of "active" fluid diffusion in severe hepatic trauma. Materials and methods: The case of a baby girl with hepatic laceration and extensive sub-capsular fluid accumulation is reported. Imaging findings are presented after ultrasound, CT without and with contrast enhancement, and MRI during the dynamic and delayed phases after Gd-BOPTA administration. Results: Ultrasound and CT examination performed with and without contrast enhancement correctly identified the hepatic laceration and sub-capsular fluid accumulation but was unable to determine whether this was hematic, biliary or mixed in nature. Contrast-enhanced CT did not reveal any extravascular contrast agent diffusion. Dynamic MR imaging, performed immediately afterwards with Gd-BOPTA, confirmed the absence of extravascular hematic fluid diffusion. MR images acquired 1 -3 and 12 hours after Gd-BOPTA administration demonstrated significant diffusion of the CM during the biliary excretion phase, thereby indicating the nature and the progression of the accumulation. The findings on delayed phase imaging with Gd-BOPTA significantly altered the patient's treatment from a previously envisaged consevative approach to an approach involving surgical intervention. Conclusion: In cases of severe hepatic trauma when associated biliary laceration is suspected, Gd-BOPTA is able to define the type of fluid diffusion occuring and to influence the appraoch to treatment.

Hepatic hemangioendothelioma of infancy: Sonographic diagnosis and follow-up. Review of four cases M. Vakaki, C. Koumanidou, H. Manoli, A. Anagnostara, G. Pitsoulakis, K. Kakavakis; Athens/GR Purpose: Infantile hemangioendothelioma (IH) is a rare vascular tumour of early infancy associated with cutaneous hemangiomas in 45 % of cases. Although benign, it can be life-threatening because of heart failure, intraperitoneal hemorrhage or thrombocytopenia. The purpose of this study is to present the sonographic appearance of IH, and the changes during its medical (steroids or interferon-a) treatment. Materials and methods: We retrospectively studied the ultrasound images (before, during and after treatment) of 4 infants with IH. Three of them also had cutaneous hemangiomas. The sonographic diagnosis was, in all cases, confirmed with CT. Liver biopsy was not performed due to the typical imaging appearance. Results: In 2 infants, 45-days and 3-months-old respectively, the abdominal sonogram demonstrated multiple, round, well-defined, hypoechoic hepatic lesions, which progressively regressed in size and number and were replaced by normalappearing hepatic parenchyma. In the first case, the IH regressed spontaneously during a 3-month period and in the second case, it disappeared after a 4-months of steroid therapy. The abdominal sonogram, in two more infants, 2-and 28-daysold, showed hepatomegaly and multiple lesions of mixed echogenicity in both hepatic lobes. The patients underwent steroid and interferon-a therapy for 9 months and 3 months respectively, with excellent results. Sonograms, performed repeatedly over a 1-year period, revealed decrease of the liver size, involution of the IH, with only tiny remaining clusters of calcification, in one case. Conclusion: Sonography, being simple and non-invasive, is particularly useful, not only in the diagnosis but also in the follow-up of conservative IH treatment. The use of US contrast in the differential diagnosis of lymph node enlargement in children -preliminary report E. Dybiec, A. Brodzisz, M. Wielosz, P. Wieczorek; Lublin/PL Introduction: Despite the technological progress in diagnosis, there are difficulties that persist in differentiating benign from malignant or metastatic lymph node enlargement. Purpose: The aim of the study was to assess the diagnostic value of US contrast in the differential diagnosis of lymph node enlargement in children. Material and methods: US examinations were performed in 32 children with lymph node enlargement of varying aetiology. Each patient was examined with B Mode, 3D, THI and Doppler modes before and after Levovist (Schering) injection in a concentration matching the weight of the patient. Examinations were performed using a Sonoline Elegra scanner with 2 -9 MHz transducers. In each examination, the shape, diameters, number of vessels and their architecture and distribution were analysed before and after contrast. The results of these examinations were subjected to comparative statistical analysis.

The results show that the use of US contrast significantly improves the visualization of the number of vessels, their distribution and architecture. The use of contrast also improved the Doppler spectral signal. This evaluation can constitute the basis of establishing the pattern of vessel distibution and architecture for benign vs. malignant lymph node enlargement in children. This procedure provides an alternative to reduce the number of invasive and ionising radiation techniques.

Sonographic appearance of regenerative nodular hyperplasia of the liver in children previously treated for malignant tumour M. Vakaki, C. Koumanidou, A. Anagnostara, H. Manoli, G. Pitsoulakis, K. Kakavakis; Athens/GR Purpose: The detection of hepatic nodules in children previously treated for malignant tumour raises the suspicion of metastases. However, they can represent the uncommonly described benign regenerative nodular hyperplasia of the liver. The aim of this study was to present the sonographic pattern of these lesions. Materials and methods: The sonographic findings of 3 children, that were 6, 13 and 14 years old, were studied retrospectively. The primary tumours were neuroblastoma, rhabdomyosarcoma and sarcoma, respectively. Results: Hepatic lesions were detected incidentally, on sonograms, during systematic, protocol-based imaging follow-up, 4 -5 years after completing treatment. There were multiple, iso-or slightly hypoechoic intrahepatic nodules in two cases and a single, slightly hyperechoic one, in the third case. The lesions measured 9 -32 mm, were located in both lobes and were surrounded by a hypoechoic rim. CT, in all children, and MR in one, confirmed their benign nature. A follow-up period of 6 -12 months was obtained in all cases, with no change in the sonographic findings. Metastases were excluded on the basis of the benign radiological features, the known, although uncommon, possible combination between antineoplastic treatment and nodular regenerative hyperplasia of the liver, and the clinical and sonographic follow-up. Conclusion: Benign hepatic hyperplastic nodules with the above sonographic features, may be detected incidentally even a long time after treatment for a malignant tumour in children. We believe that in the absence of any other clinical, laboratory or radiological signs of disease progression, close sonographic follow-up should be sufficient to rule out metastases.

Sonographic "daughter cyst" sign in the diagnosis of ovarian cysts in neonates, infants and children M. Vakaki, C. Koumanidou, A. Anagnostara, H. Manoli, K. Kakavakis; Athens/GR Purpose: To assess the value of the "daughter cyst" sign in the differential diagnosis of ovarian cysts from other cystic masses in girls, as being clinically important for their therapeutic approach. To our knowledge, there are only few cases reported in the literature.

The abdominal sonograms of 18 children (age range 4 days to 14 years) with a lower abdominal cystic mass, were retrospectively studied. Cystic masses arising from the kidney or biliary tract were excluded. The "daughter cyst" sign was defined as the presence of a small cyst along the wall of a cystic mass. Results: The 18 cystic masses included ovarian cyst (n = 8), intestinal duplication cyst (n = 4), Meckel's diverticulum (n = 1), hematocolpos (n = 2), hematometra (n = 1), lymphangioma (n = 1) and a mesenteric cyst (n = 1). The daughter cyst sign was seen in 6 (75 %) of 8 ovarian cysts, but in none of the other cystic masses. The size of the daughter cysts ranged from 2 to 8 mm and their number, in each ovarian cyst, from one to three. Three ovarian cysts with the above sign were surgically managed. One of them was additionally complicated by torsion diagnosed intraoperatively. The sonographic daughter cysts corresponded to follicles on pathologic examination. The ovarian cysts of three neonates with this sign spontaneously involuted during the first months of life. The remaining 12 cystic lesions were surgically confirmed. Conclusion: When the "daughter cyst" sign is sonographically identified in a cystic mass in neonates, infants and children, the diagnosis of ovarian cyst can be suggested with confidence.

Kabuki syndrome -a pictorial review of radiological and clinical signs G.K. Schneider, K. Altmeyer, B. Kramann, S. Aliani; Homburg a. d. Saar/DE Kabuki syndrome is a rare multiple congenital anomalies/mental retardation syndrome which is characterized by a distinct face, mild to moderate mental retardation, postnatal growth retardation, dermatological and skeletal abnormalities. The aim of this exhibit is to demonstrate an overview of the variety of radiological as well as clinical findings which can typically be seen in Kabuki syndrome. Typical skeletal anomalies like a short or curved fifth finger, deformed vertebrae and hip dislocation, genitourinary and cardiovascular malformations as well as images of the facial appearance which suggest Kabuki syndrome will be presented. Findings associated with Kabuki syndrome reported in the literature will be discussed. Since radiologists should be aware of this rare multisystem disorder a combination of radiological and clinical findings that strongly suggest the diagnosis will be outlined including possible differential diagnoses. Since early detection of disease related complications can prevent further comorbidity, emphasis will also be put on manifestations which may occasionally result in acutely occuring sometimes life-threatening conditions.

Central venous catheter placement: A pictorial review of complications on the plain radiograph N.A. Barnes, M. Singh, H.M.L. Carty; Liverpool/GB Purpose: Central venous line (CVL) placement in children and adults can be extremely difficult and result in serious complications. The plain radiograph has a vital role in identifying the site of the CVL. As routine practice, radiologists and clinicians are taught to check CVL position, but the significance of this is sometimes not appreciated. Materials: We present several cases of lines seen in abnormal positions on plain radiographs that can be used to illustrate useful anatomical and clinical lessons in children. We discuss the possible consequences of placing lines incorrectly and stress the importance of careful review of plain films in the knowledge of children's anatomical variation. Target audience: Radiology trainees, the occasional paediatric radiologist.

Thoracic congenital vascular anomalies: Conventional and 3D gadoliniumenhanced MR angiography M. Andreu, C. Martín, A. Darnell, V. Medina, A. Quiles, P. Melloni; Sabadell/ES Objective: To evaluate the usefulness of conventional and three-dimensional (3D) gadolinium-enhanced magnetic resonance (MR) angiography in the study of thoracic congenital vascular anomalies. Material and methods: We performed MR, with a 1.0 T Unit, in 105 patients (ranged from 1 month to 16 years) with a history and/or X-ray film suggestive of thoracic vascular anomalies. In 75 patients we used T1 weighted electrocardiographicgated spin-echo pulse sequences. The others 30 patients underwent 3D MR Angiography sequences (Spoiled gradient echo) during gadolinium administration. Whenever it was possible we obtained the images during apnoea. The dose of contrast material was 0.4 mmol/kg. Oesophagram and bronchoscopy were occasionally performed. Results: We detected aortic anomalies (n = 35), supraaortic vessel anomalies (n = 16), pulmonary artery anomalies (n = 6), pulmonary venous anomalies (n = 5), superior vena cava anomalies (n = 8) and miscellaneous abnormalities (n = 10). 25 patients had a normal examination. Conclusions: Both, conventional and 3D gadolinium-enhanced MR Angiography, are techniques that can be used to investigate mediastinal vascular anatomy. However, 3D gadolinium-enhanced MR Angiography is a faster and more accurate imaging modality. Purpose: Our country's legislation requires the following criteria: apnoea, absence of brain stem reflexes, two isoelectrical EEG, 6, 48 and 72 hours apart and in patients less than three years of age selective dynamic radionuclide cerebral angiography (HMPAO perfusion). The purpose of this study was to compare cerebral blood flow by dynamic radionuclide and Doppler studies. Material and methods: We performed 60 Doppler transcranial ultrasound scans in patients with a mean age of 10.5 years; 27 males and 33 females. All patients were evaluated by duplex-Doppler using 7, 3.5 and 2 MHz transducers. The middle cerebral and internal carotid arteries were scanned bilaterally. Results: In order to compare the efficacy of both methods, two groups were made: group I, clinically brain dead patients (35) and group II, a control group (25) Spectral flow patterns can be divided into three groups: normal flow, reversible flow and non reversible flow (Reverse diastolic flow without diastolic forward flow and brief systolic forward flow). The brain dead group presented with non reversible flow in all cases. Both methods were concordant in determining the presence of brain death, either by absence of flow by the HMPAO method or by a brain dead pattern with the Doppler technique. Conclusion: 99 Tc HMPAO is the gold standard in the diagnosis of brain death. There is a 100 % concordance between spectral analysis of internal carotid and middle cerebral arteries and isotope studies in the diagnosis of cerebral blood flow arrest. Doppler is a safe, non invasive, unexpensive and clinically useful technique in the assesement of brain death. 

We reviewed the medical records of 22 children (14 boys and 7 girls) diagnosed with tumours of the thalamus or the basal ganglia, seen at our hospital from 1980 to 2000. We especially assessed clinical features, correlating clinical features with the topography of the lesion, and conventional imaging findings (computed tomography and magnetic resonance imaging). Results: Histological diagnoses were astrocytoma (16), oligodendroglioma (1), pleomorphic xantoastrocytoma (1), ganglion cell tumor (2), lymphoma (1), and metastasis (1). 20 % of patients had an acute presentation although the majority of presentations were subacute. Symptoms and signs of raised intracranial pressure (65 %), motor deficits (40 %) and seizures (35 %), alone or in combination, were the most frequent manifestations. Imaging findings were non-specific although certain locations and morphological features (intensity, cysts and calcifications) can help to suggest certain subtypes. Conclusion: Among brain tumours, those arising from the deep brain are rare. The vast majority are low-grade astrocytomas. Other neoplams are infrequent. Although the different macro and microscopical characteristics of brain tumours are often in the basis of the imaging findings, CT and MRI data usually overlap and make conventional imaging only useful as an approximation tool. However, nonastrocytic neoplasms sometime differ from astrocytomas. These imaging peculiarities may help to suggest a histologic subtype. Clinical manifestations reflect the effect of pressure on the ventricular system, the thalamic nuclei the corticospinal fibres and the optic radiations.

Application of 3D, THI and Doppler US mode imaging to visualise enlarged lymph nodes in children P.

Wieczorek, E. Dybiec, A. Brodzisz, M. Wielosz; Lublin/PL Introduction: B-Mode US imaging often encounters difficulties in the evaluation of deeply located lymph nodes and examination artefacts. The introduction of 3D THI and Doppler modes increases the diagnostic value of US in enlarged lymph node evaluation. Purpose: The aim of the study was to test the usefulness of 3D THI and Doppler US modes in enlarged lymph node evaluation. Material and method: US examinations were performed in 48 children, using a Sonoline Elegra scanner with 2 -9 MHz transducers. The examination was performed in B Mode, and then in 3D, THI and Doppler modes. The results were subjected to comparative statistical analysis in order to evaluate he diagnostic value of each mode, and to formulate an optimum diagnostic algorithm in the case of lymph node enlargement in children. Results and conclusions: Statistically significant differences were found between THI and 3D vs. B Mode. The use of 3D imaging facilitated the examination of vascular architecture, while colour and power Doppler showed the distribution of vessels. Spectral Doppler showed haemodynamic changes (PI, RI) of flow during the treatment. THI significantly improved the quality of visualisation by reducing the number of artefacts. Combining these methods in patients with enlarged lymph nodes allows a better and more precise differentiation between benign, reactive and malignant lymph node enlargement.

Computer processing (by ROC analysis) in standardization of ultrasound findings in benign viral diseases of lymph nodes in children S.B. Stajic; Pancevo/YU Purpose: In a continuous effort to standardise various ultrasound findings we employed a computer processing programme for ROC analysis (Receiver Operating Characteristic) for a number of sonographic criteria in benign viral diseases of lymph nodes. Methods and materials: In the last two years we have collected the sonographic criteria of lymph nodes in 178 patients (68 with infective mononucleosis, 17 with cat scratch disease and 93 with atypical viral disease). The clinical staging, laboratory findings, CT and PH findings confirmed the presence of benign viral infections. We used our software for processing ultrasound findings with the graphic distribution of each sonographic parameter by the ROC curve (localization, thickening of cortex, size, shape, border, pattern, hilus and posterior effects). Results: The presence of oval shaped lymph nodes (90 %), a well defined border (72 %), hypoechoic and heterogenous echo pattern (73 %), the presence of a well defined echoic hilum (74 %), thickening of lymph node cortex (87 %), size less than 0.8 cm (91 %) and discrete posterior shadowing (68 %) had the best sensitivity in viral diseases of lymph nodes. The highest accuracy was shown by thickening of the lymph node cortex (87 %), a well-defined border (74 %), oval shape (81 %), size less than 0.8 cm (76 %) and the presence of well-defined hyperechoic hilum (79 %). Conclusion: We continuously emphasize the importance of cummulative values, and the testing of each sonographic criteria by this computer programme as a useful diagnostic tool in the decision-making process and presumably effect therapy and the prognosis of the disease therefore increasing the cost effectiveness of ultrasound examinations.

A pictorial review of MR imaging of neck masses in infants and children M. Sambrook, A.J.B. Watt; Glasgow/GB Purpose: To demonstrate MR imaging techniques in the wide variety of pathologies that may affect the head and neck within the paediatric population.

A retrospective review of the last 30 cases referred to a large paediatric centre. Age range was from 3 days to 15 years. MR imaging was performed on a Philips Gyroscan NT 1.5 T MR Unit. Most patients were imaged unsedated but some required general anaethesia. MR was used to supplement ultrasound and provide subtle discrimination of soft tissue characteristics with the aim of non-invasively defining the precise pathology where possible, and delineating the extent of invasion. A large number of sequences was often required to achieve this end, including T2 single shot TSE, fat suppressed T2 & T1 post contrast sequences and 3D volume sequences. Results: All MR scans were technically successful. MR imaging of our series of patients identified several of the most common conditions in the paediatric neck as well as some uncommon ones. Pathology included cystic hygroma, haemangioma, venous malformation, branchial cleft cyst, thryroglossal cyst, dermoid cyst and thyroid carcinoma. Specific attention was made to optimize the MR sequences to give the best imaging results for these conditions in the paediatric polpulation. Conclusion: MR imaging of paediatric neck masses provides detailed anatomical information not easily obtained by other means and can also give an indication of the likely diagnosis as well as assessing any complications. Doses to patients in conventional and digital X-ray chest examinations in two Bulgarian hospitals A.A. Dimov 1 , J.N. Vassileva 2 ; 1 Sofia/BG, 2 Shumen/BG Purpose: Over recent years in Bulgaria the number of tuberculosis cases has risen. This has resulted in the need to introduce a large scale chest radiograph screening program. At the same time, there has been an increased emphasis placed on both assessment and reduction of patient doses, imposing new and higher standards. Materials and methods: This study includes 24 adult patients with standard anthropomorphic data. For each patient the FSD, exposure parameters, Kerma area Product (KAP) as well as the personnel anthropomorphic data are given. The effective dose (E) and the chest dose for every patient are calculated using different Monte Carlo (MC) simulations. The typical Effective dose (ET) is calculated for both cases and is converted into Background Equivalent Radiation Time (BERT). The results are compared with the European and International diagnostic reference levels. Results: The typical Effective doses are 16 µSv and 371 µSv, BERT is 2.5 and 59 days and absorbed dose to lungs (D) is 0.048 mGy and 1.56 mGy for the digital and conventional X-ray system respectively. Conclusion: The great difference in the patient doses is due not only to the type of equipment, but also to the use of old film-screen combinations in the second hospital. A significant possibility for the patient dose reduction is yielded by the application of modern imaging systems. The optimisation of the patient exposure should be done in concert with the ALARA principle.

Analysis of radiologist performances with and without a CAD system A. Lauria, R. Palmiero, M. Imbriaco, G. Selva, A. Sodano, P.L. Indovina; Naples/IT Purpose: The aim of this work is to test the performances of two radiologists with different experience, with the aid of the SecondLook CAD system. Methods and materials: We considered a dataset composed by 12 healthy cases (48 images with the gold standard being at least 3 years clinical follow up), and by 28 malignant cases (79 images with the gold standard being the final histopathological diagnosis). Mammograms were randomly interpreted by two radiologists: radiologist A, with 5 years of experience in mammography and radiologist B, with 2 years of experience. They independently and blindly (unaware of the final diagnosis) read the exams. One month later they reviewed and read the same mammograms with the help of CAD printout. The diagnosis, with and without the CAD, were compared in terms of sensitivity and specificity. Results: For radiologist A, the sensitivity and specificity with the help of CAD system was 92 % and 87 %; without CAD system 90 % and 98 %, respectively. Conversely, for radiologist B the sensitivity and the specificity with the help of CAD system was 90 % and 83 %; without CAD system 86 % and 92 %, respectively. Conclusion: The use of the CAD system improves the radiologist performance in terms of sensitivity. This is independent of the experience in mammogram reading. We believe that the CAD system may recall the radiologists attention to some regions previously misclassified.

Evaluation and analysis of two CAD systems for early detection of breast cancer R. Palmiero 1 , A. Lauria 1 , U. Bottigli 2 , P. Delogu 3 , M.E. Fantacci 3 , S.S. Tangaro 4 ; 1 Naples/IT, 2 Sassari/IT, 3 Pisa/IT, 4 Bari/IT Purpose: In this paper two CAD systems, designed to highlight Regions Of Interest (ROIs) on the mammograms, were compared. The aim of the two CAD systems is to call the radiologist's attention to suspect regions supporting them in their diagnosis. Methods and materials: It has been decided to compare the performance of the SecondLook system (by CADx) and the CAD CALMA in the research of the microcalcification clusters. The first is a commercial system realized in Canada, the second one is developed in the homonymous project from Istituto Nazionale di Fisica Nucleare. The significant difference between the two CAD systems consists in the image storage and output presentation. The figures used for comparison are sensitivity (correct classified positives/true positives) and specificity (correct classified negatives/true negatives). In this work we consider a dataset composed by 12 healthy cases (48 images), and by 28 malignant cases (79 images). Results: The Sensitivity and the number of false positives per image have been reported. The sensitivity is 0.70 for the SecondLook CAD system and 0.68 for the CAD CALMA. The SecondLook presents 0.08 false positives fraction, and CAD CALMA 0.62. Conclusion: While the sensitivity's values of the two systems are equal, the number of false positives per image is better for SecondLook. Since the CAD CALMA is an opened system, we are working to improve its performance. Moreover we observed that the false positives regions highlighted by CAD CALMA are smaller than the SecondLook ones and the global area of false positive regions result comparable.

Frequency analysis of CSF flow on cine-MRI in normal pressure hydrocephalus T. Miyati 1 , H. Fujita 2 , M. Mase 3 , T. Banno 3 , T. Kasuga 1 , K. Yamada 3 , K. Koshida 1 , S. Sanada 1 , H. Imai 1 ; 1 Kanazawa/JP, 2 Gifu/JP, 3 Nagoya/JP Purpose: To clarify the flow dynamics of intracranial cerebrospinal fluid (CSF) in normal pressure hydrocephalus (NPH), frequency analyses of CSF flow measured with a phase contrast cine-MRI were performed. Material and methods: The amplitude and phase in the CSF flow spectra in the aqueduct were determined in patients (n = 51) with NPH after a subarachnoid hemorrhage (SAH-NPH), an idiopathic NPH (I-NPH), an asymptomatic ventricular dilation (VD), and in healthy volunteers (control group)(n = 25). The changes of CSF flow spectra were also analyzed after an intravenous injection of acetazolamide. Moreover, a phase transfer function (PTF) calculated from the spectra of the driving vascular pulsation and CSF flow in the aqueduct were assessed. These values were compared with the pressure volume response (PVR). Results: The amplitude of the 1 st -3 rd harmonics in the SAH-NPH or I-NPH group was significantly larger than in the control or VD group because of a decrease in compliance. The phase of the 1 st harmonic in the SAH-NPH group was significantly different from that in the control or VD group, but no difference was found between the control and VD groups. The amplitude of the 0 -3 rd harmonics increased, and the phase of the 1 st harmonic changed in all groups after an acetazolamide injection. A PTF of the 1 st harmonic in the SAH-NPH group was significantly larger than in the control group, and a positive correlation was noted between PTF of the 1 st harmonic and PVR. Conclusions: Frequency analyses of CSF flow measured by cine-MRI make it possible to obtain noninvasively a more detailed picture of the pathophysiology of NPH.

Determination of an image quality index from threshold contrast detail diagrams I.A.J. Fife, I.R. Pitkin; London/GB Purpose: A novel image quality (IQ) index using threshold contrast detail diagram data is presented. Methods and materials: A threshold contrast detail test object has been used to obtain data on fifteen fluoroscopy units. The data recorded has been plotted as threshold contrast versus object size and fitted to a rectangular hyperbola. The distance, c, from the origin to the curve apex has been calculated and used to form a measure of IQ. Threshold Contrast Detail Diagrams (TCDDs) and Threshold Detection Index Diagrams (TDIDs) have been compared with c −2 , a proposed IQ index. Results: The use of c −2 as an IQ indicator agrees well with established methods for IQ assessment, such as the area under a TDID curve and the reciprocal area under a TCDD curve. Conclusion: When the Pearson Correlation Coefficient of contrast versus reciprocal object size is > 0.95, the TCDD can be accurately plotted as a rectangular hyperbola. When this is the case c −2 is a useful IQ indicator, correlating well with the area under a TDID curve and the reciprocal area under a TCDD curve.

Measurements of MTF and SNR(f) using a subtraction method in MRI T. Miyati 1 , H. Fujita 2 , M. Mase 3 , T. Banno 3 , T. Kasuga 1 , K. Yamada 3 , K. Koshida 1 , S. Sanada 1 , H. Imai 1 ; 1 Kanazawa/JP, 2 Gifu/JP, 3 Nagoya/JP Purpose: A method was developed to accurately measure modulation transfer functions (MTFs) and signal-to-noise ratios (SNRs) in the positive and negative frequencies of magnetic resonance images (MRI). Material and methods: The MTF was calculated from the line spread function obtained by a process of subtraction of the complex images, with and without slit, using an original phantom. The phantom was structured so that a thin polyethylene terephthalate sheet in a Plexiglas guiding frame could be inserted and removed from a hemispheric Plexiglas container. Moreover, SNR(f) was calculated from the MTF and the Wiener spectrum, both of which were determined with the same phantom and setting. The MTFs and SNR(f)s in the conventional spin echo (SE) and Turbo SE which set effective echo time at the first echo were evaluated by changing the T2 of the phantom in the frequency and phase encode directions. Results: MTFs indicated the characteristics of the k-space trajectory in each pulse sequence. SNR2(f)s gave positive and negative spatial frequency information that was not obtained with conventional methods. In this method, the influences of image nonuniformity and unnecessary artifacts could be eliminated. Conclusions: Analysis of the MTF and the SNR in the spatial frequency domain made it possible to obtain more detail on the image quality of MRI.

Comparison of organ and effective doses of single-slice versus multi-slice CT of the body M. Cohnen, L.W. Poll, A. Saleh, C. Püttmann, A. Scherer, K. Ewen, U. Mödder; Düsseldorf/DE Purpose: To assess radiation exposure in multi-slice CT (MSCT) and single-slice CT (SSCT) of the chest and abdomen. Material and methods: Three scanning protocols each for chest and abdomen were performed on a "Somatom Plus 4 Volume Zoom" MSCT (Siemens, Germany) with changing slice collimation (4 × 1, 4 × 2.5, and 4 × 5 mm), and pitch-factors (1, 1.5, and 2). Effective doses were calculated from LiF-TLD measurements at several organ sites using an Alderson-Rando phantom and compared to data from SSCT of chest and abdomen (5 mm, pitch 1.6; "Somatom Plus 4", Siemens), and to calculations using weighted CTDI. Results: Effective dose in chest-MSCT varied from 7.0 to 12.1 mSv, and in abdomen-MSCT from 11.8 to 15.3 mSv, respectively. Highest organ doses were 20 to 25 mGy for lung, liver, esophagus and skin in chest-MSCT, and 22 to 25 mGy for gonads, liver, colon and skin in abdomen-MSCT, respectively. Effective dose in chest-SSCT was 3.6 mSv, and for abdomen-SSCT 9.4 mSv, respectively. Calculation of the effective dose differed from measured data by up to −33 %. Conclusions: Effective dose applied in standard protocols for MSCT of chest and abdomen is higher than in SSCT. Data from phantom measurements show important differences compared to calculations using weighted CTDI.

Measurements of X-ray energy dependence of an imaging plate T. Fujisaki 1 , K. Nishimura 1 , S. Iijima 1 , S. Abe 1 , H. Saitoh 2 ; 1 Ibaraki/JP, 2 Tokyo/JP Purpose: A photostimulable phosphor plate (imaging plate, IP) used as an image detector has properties of high sensitivity and wide dynamic range that cannot be obtained with an X-ray film. Although research into image characterisation for radiodiagnosis has been carried out, so far there has been little work on the X-ray energy dependence of IP. The IP response and characteristic curve for the X-ray energy were measured in order to evaluate the X-ray energy dependence of IP. Material and methods: The IP response for the X-ray energy was evaluated from the monochromatized X-ray absorption rate, which in turn was calculated from the relative intensity of photostimulated light (pixel value). A CR system was employed in image data acquisition of the irradiated IP. The measurement of the characteristic curve for the X-ray energy was also performed using the time scale method. Results: The IP response varies considerably in the X-ray energy region used in diagnostic radiography. It is necessary to correct the X-ray energy dependence when IP is used for the radiation measurement. The gradient of the characteristic curve for the X-ray energy does not change in the X-ray energy region of diagnostic radiography. Conclusion: (1) The IP response varies considerably in the X-ray energy region of diagnostic radiography. (2) The X-ray energy dependence of the characteristic curve is not found in the X-ray energy region of diagnostic radiography.

Observer performance evaluation and dose impact for two digital detectors used in thoracic radiology L. Parent, P. Duthil, P. Otal, F.G. Joffre, I. Berry; Toulouse/FR Purpose: Digital detectors have recently been introduced into radiology, showing promising intrinsic performances and great potential for patient dose reduction. This study aims to evaluate the dose impact on the image quality for two digital detectors used in radiology for thoracic imaging at our institution. Material and methods: The two compared systems were a storage phosphor detector and an amorphous silicon flat panel detector. Image quality evaluation was performed using a CDRAD phantom. Radiographs were acquired at various skin dose levels and were read out by a group of 8 readers. Contrast versus detail curves were plotted and inverse Image Quality Figures (IQFinv) were calculated. Results: A significant superiority of the amorphous silicon flat panel was observed at equivalent dose levels (17.3 % IQFinv increase). Contrast versus detail plots and IQFinv comparisons at various dose levels showed that same performance can be achieved with a dose reduction of 55 % for the amorphous silicon flat panel detector. Furthermore, the amorphous silicon flat panel image quality versus dose level curve was found asymptotic. Conclusion: Among digital detectors, the amorphous silicon flat panel showed the most promising potential in dose reduction. Nevertheless, a clinical evaluation of both detectors should be performed in order to confirm these conclusions.

Polymer gel dosimetry using 3-dimensional (3D) magnetic resonance imaging (MRI) sequences P. Kipouros, P. Papagiannis, E. Pappas, P. Karaiskos, P. Baras, I. Seimenis, P. Sandilos, L. Vlachos; Athens/GR Purpose: Polymer gel dosimetry is a promising method for accurate dose distribution measurements. In this work we present measurements of full 3D dose distribution data around a brachytherapy source, obtained within reasonable imaging times, through the use of a 3D, multiple spin echo MR imaging sequence, suitable for polymer gel dosimetry. Materials and methods: N-vinylpyrollidone based (VIPAR) polymer gels were prepared and were subsequently irradiated with a 192 Ir brachytherapy source with either single source dwell position irradiations (10 Gy at 10 or 7 mm radial distance) or intravascular (14 Gy at 6 mm) protocols. T2 relaxation time maps of the irradiated volume were obtained in multiple planes using a volume selective, multiecho sequence with optimized scan parameters and were converted to dose maps through an appropriate calibration procedure. The obtained dosimetric results were compared to corresponding data derived from the AAPM TG43 protocol. Results: The dose range examined covered two orders of magnitude and measurements were performed in the mm distance range of the source. MRI obtained data were found to be in good agreement with TG43 data. The 3D MRI readout method of polymer gels used in this work provided increased spatial resolution and allowed the determination of three dimensional dose distributions within the irradiated volume. The method can also be used for the reconstruction of isodose contours in any desired plane. Conclusion: 3D MRI imaging techniques can be of particular use when complicated radiation regimes, resulting in steep three dimensional dose gradients, are investigated.

Patient dose and radiation risk in paediatric radiology in Estonia K. Kepler 1 , A. Servomaa 2 , M. Lintrop 1 ; 1 Tartu/EE, 2 Helsinki/FI Purpose: This study was undertaken to introduce dose-area-product (DAP) and entrance surface dose (ESD) measurement methods as a part of quality assurance (QA) program in Estonian paediatric radiology, and to provide data on magnitudes of DAPs for single radiographic projections for different age groups, which could be used for comparison of patient doses reported in other studies. Materials and methods: Radiographic examinations of the pelvis, chest, spine and head were studied. Data were collected for 319 radiographs of children referred to the X-ray Department of Tartu Children's Hospital during a 4-month period. The exposure factors were recorded along with details of patient data and DAP readings. Uncertainty in DAP measurements was estimated as 10 -17 % (dependently on kVp and DAP values). ESD to patient was estimated from the DAP measurements and by calculations using the data of X-ray tube output and examination techniques. Effective dose was calculated by using the program PCXMC. 

Results: Average ESDs for 5 a patients in chest, pelvis and lateral head examinations were respectively 0.097 mGy, 0.45 mGy and 0.57 mGy. Doses for the same projections differed usually in the age groups up to 5 times. Effective dose varied in different age groups and projections from 0.002 mSv to 0.2 mSv. Conclusion: The methods and results of this study can be used for developing the system of QA and patient dose measurements. The doses in this study are comparable with the European diagnostic reference levels and with doses of good clinical practice of other countries.

Effective dose in X-ray examinations: Comparison between unenhanced helical CT (UHCT) and intra venous urography (IVU) in the evaluation of renal colic A. Rimondini, M. de Denaro, P. Bregant, R. Pozzi-Mucelli; Trieste/IT Purpose: To calculate the effective dose in UHCT and IVU performed for renal colic. Materials and methods: Dose measurements were performed by employing thermoluminescence detectors (TLDs) loaded inside an anthropomorphic phantom. The data were compared with dose estimations based on published tables. Results: The absorbed dose inside the phantom had an homogeneous distribution during UHCT examination, while during IVU the distribution was disomogeneous. The mean effective dose for UHCT was 3.3 times that for IVU (6 mSv versus 1.8 mSv). Concerning both techniques, the dose was significantly lower in males than in females, for the different anatomic position of the gonads. The evaluation of effective dose in UHCT, based on CTDI value, underestimated the TLDs measurement (5.2 mSv versus 6 mSv). The evaluation of effective dose in IVU, based on the measurement of the skin dose on air, overestimated the TLDs measurement (2.3 mSv versus 1.8 mSv). Conclusion: The experimental measurement of the dose during UHCT is quite difficult, and introduces imprecisions due to the simplified morphology of the phantom and the measuring system of TLDs (± 10 %). Otherwise, the theoretical estimations are also affected by imprecisions due to patient geometry. The same considerations can be applied to the IVU; in this case the theoretical estimations are very accurate but cannot foresee X-rays distribution inside the patient. The effective dose for the UHCT resulted 3.3 times that for IVU; however, the high intrinsic contrast of stones probably make possible to acquire low dose UHCT examinations without lost of image quality.

Individual relative risk of malignant neoplasms in the liquidators of the Chernobyl accident consequences according to the data of cytogenetic studies V.T. Demin, E.A. Djomina; Kiev/UA Purpose: To ground the purpose of the formation of liquidators critical groups with increased individual relative risk of malignant neoplasm on the basis of study of cytogenetic changes in peripheral blood lymphocytes as cancerogenous factors. Materials and methods: To evaluate the individual relative risk the cohort of liquidators was stratified into two groups: (1) exposed persons with malignant neoplasm; (2) exposed persons without neoplasm. Then the degree of cytogenetic proximity in these groups was defined. The working hypothesis was that absolute risk is directly proportional to the index of individual proximity to the index of the group with malignant neoplasia. Results: The index of chromosome aberration quantity has the lowest informativity under the cohort stratification into the groups with malignancy and without, and the frequency of fragments pairs and chromatid aberrations, the highest. It was stated that the individual relative risk of malignant neoplasm in the investigated cohort is distributed unevenly, and over than a half of the liquidators has higher risk compared to the whole cohort. Conclusion: As a basis for cytogenetic investigation of liquidators and the identification of critical groups of oncology risk the best approach is to take into account the level of pair fragments of chromosome origin and chromatide aberrations.

Quantitative ultrasound imaging: Algorithm development and clinical assessment of a region growing technique J. Damilakis, J. Stratakis, K. Perisinakis, N. Gourtsoyiannis; Iraklion/GR Purpose: To develop and evaluate a region-growing algorithm for selection of an irregular region of interest (ROI) in broadband ultrasound attenuation (BUA) images.

The algorithm was written in Image Pro BASIC (IPBASIC), the programming component of Image Pro Plus (Media Cybernetics Ltd., Silver Spring, MD). The algorithm searches an initial region in the greater tuberosity of the calcaneus until the pixel with the lowest attenuation value is found; this is the starting seed. Then, the algorithm evaluates the values of the pixels neighboring to the starting seed. Pixels that have the closest value to the starting seed are accepted. This procedure is the first processing level. The procedure is repeated for the pixels neighboring those accepted from the previous processing level. The algorithm ceases when the number of accepted pixels reaches a user-specified number. The algorithm was applied to images obtained from 24 postmenopausal women with hip fractures and 26 age-matched healthy female subjects. Results: BUA measurements at the irregular ROI with size 2400 pixels enable better differentiation of diseased subjects from healthy individuals (area under ROC curve 0.815 vs 0.792) and better correlation with hip BMD (r = 0.58 vs 0.47) and age (r = −0.64 vs −0.52) as compared with measurements at a circular automatic ROI selected by the software of our quantitative ultrasound imaging device. Conclusion: The irregular ROI selected by the algorithm developed in this work yielded better clinical results compared to a circular automatic ROI implemented on a quantitative ultrasound imaging device. Material and methods: The flow system (Flow Solutions Inc., Alamo, USA) consists of a conventional pool pump and a closed plastic tube cycle (ID 15.5 mm). Steady flow rates up to 75 ml/s can be adjusted manually with two 3-way-valves and a main valve. By using an electromagnetic shutter-valve different pulsatile flow conditions can be produced simulating physiologic flow waveforms. Flow measurements were performed with 2D-PCA-FLASH sequences on a 1.5 T scanner (Venc 40 and 75 cm/s). CINE-mode was used for pulsatile flow (triggered by the valve-signal, 64 phase images). Two simple perfusion phantoms were built and integrated into the flow circuit. Both T1-weighted saturation recovery images and T2*-weighted EPI images were acquired to track the time course of a bolus of contrast agent. Results: Simulated pulsatile flow data were analyzed off-line with a MATLAB program and compared with in-vivo carotid flow measurements. Velocities as well as flow rates were similar to physiological data. Perfusion images of the phantoms were evaluated by using ROIs to obtain signal intensity-time-curves. Both phantoms produced organ mimicking time curves. Conclusion: The flow phantom is a simple and robust system, which can be used to simulate different flow conditions and to extract corresponding flow parameters. Due to its flexibility it is easy to handle, especially for integration and testing of different home-built phantom units.

1 H-NMR spectroscopy: Comparison of SNR data in different MR systems during acceptance testing P. Berardi 1 , C. Bergamini 1 , L. Selleri 1 , R. Tarducci 2 ; 1 Bologna/IT, 2 Perugia/IT Purpose: A simple and fast method to verify the main physical parameters during the acceptance test in MRS has been implemented. Data has been collected from different MRS systems (three GE Signa-Horizon 1.5 T units) in order to compare them. After the MRS acceptance tests were carried out in June 2000, a quality assurance program has been developed through monthly checks. Materials and methods: A sphere filled with a metabolite solution placed at head coil isocenter has been used as test object and PRESS and STEAM used as acquisition sequences. During acceptance testing the following measures were performed: (a) Signal linearity: increasing voxel size from 1 cm 3 to 64 cm 3 ; (b) Signal uniformity: moving a fixed size voxel (8 cm 3 ) along x, y, z direction; (c) Signal contamination: moving the test object along z-axis with 8 cm 3 volume; (d) Voxel position: acquiring an image of the voxel and comparing it with test object image. Monthly checks: SNR and signal peaks of spectra. Results: The data collected confirm a good linearity versus voxel size. An acceptable variation of signal has been observed within voxel localization (sd < 5 %). Localization of test object along z-axis produced a low variation in signal intensity (sd < 3 %). A strong failure occurred during the use of a MRS system and the QA program showed that maintenance had not been properly carried out.

Conclusion: The QA program is a good database for statistical analysis and for control of physical parameters in time. Data collected during acceptance tests can be useful as comparison between different MRS systems.

Conceptus dose estimation during irradiation of breast with tangential fields M. Mazonakis, J. Damilakis, N. Theoharopoulos, H. Varveris, N. Gourtsoyiannis; Iraklion/GR Purpose: To estimate conceptus dose resulting from tangential breast irradiation. Methods and materials: Conceptus dose was estimated using anthropomorphic phantoms simulating the geometry of a pregnant woman at the first, second and third trimester of gestation. Breast irradiation was generated with 6 MV photon beams. Five different tangential field sizes were applied. All dose measurements were carried out using thermoluminescent dosemeters. Results: At the first trimester of gestation, conceptus dose was less than 100 mGy for a treatment course delivering 50 Gy to tumor. At the second trimester of gestation, the average conceptus dose was 45.5 -129.5 mGy depending upon field size. The corresponding average conceptus dose at the third trimester was found to be 78.0 -228.5 mGy. For both medial and lateral field irradiations at advanced gestational ages, formulas describing the dependence of the average conceptus dose upon field size and distance from field isocenter were derived. Conclusions: This study provides the necessary radiation dose data and formulas to calculate conceptus dose resulting from tangential breast irradiation at the first, second and third trimester of gestation.

Variable helical weighting algorithm for multi-detector row CT Y. Imai 1 , J. Hsieh 2 , A. Nishide 1 , Y. Shen 1 ; 1 Hino/JP, 2 New Berlin, WI/US Purpose: A helical interpolation for the multi-detector (4-row) CT high-speed data acquisition mode induces image artifacts when the distance between data samples in the projection data set is further than that of the high-quality mode, and actual and conjugate data overlap each other. We propose a special helical weighting scheme that overcomes these shortcomings and improves image quality.

The new scheme we developed changes the weightings as a function of the detector angle, forcing the plane of reconstruction (POR) to be non-parallel and non-flat to the detector row, and sets the control peak. We then created wire, disk and oval body phantoms. The slice sensitivity profile (SSP), artifact and noise characteristics were then measured using their phantoms by the special evaluation algorithm automatically. Results: Image artifact reduction is up to about 30 % and image noises reduction is up to about 10 % (in case of 5.0 mm row width and it's varying each row width) when compared to the conventional weighting method controlling the expanse of SSP slightly. And also, we could confirm reduction of stair step artifacts induced by multi-planar reconstruction (MPR) and 3D reconstruction using human body phantom and clinical images. Conclusion: This study indicates that the helical interpolation scheme changing weightings for high-speed data acquisition could reduce image artifacts and noise. This improvement also provides better quality for both MPR and 3D reconstructed images.

Calculating the composition of water and tissue equivalent materials for diagnostic radiology using tabulated tissue compositions P. Homolka, A. Gahleitner, R. Nowotny; Vienna/AT Purpose: Optimization of phantom materials mimicking water and body tissues for diagnostic radiology including CT. Methods and materials: Phantomas, a computer program to calculate phantom material compositions to reproduce X-ray attenuation of many substances including body tissues was developed. These materials are formulated using solid polymer powders (PE, PP, PS) with filling materials added to control X-ray opacity. After calculating the X-ray attenuation as a function of photon energy for the tissue using elemental tissue compositions (ICRU 44 and 46) a base polymer and a number of admixtures (typically 2 to 3) are selected. With this information, Phantomas calculates the optimum composition of the phantom material by minimizing a suitable distance function describing a weighted deviation in linear X-ray attenuation between phantom material and tissue to be mimicked. Results: Compositions for muscle, different bone tissues, adipose tissue, and water were calculated. Maximum deviations in linear X-ray attenuation coefficients between formulations calculated and the material or tissue mimicked were < 0.4 % for E = 30 to 150 keV, with mean deviations < 0.07 %. The water equivalent mate-rial (PSPP1) was produced and measured on two CT machines. HU values within 4.0 ± 2.7 (140 kVp) to 7.0 ± 5.3 (80 kVp) agreed well with water, sensitivity on spectra used was shown to be low. Conclusion: Using the algorithm implemented into the program compositions of phantom materials for diagnostic radiology including CT can easily be optimized.

Survey on dose reference levels for CT examinations in Austria H. Kudler, A. Taubeck, R. Nowotny; Vienna/AT Purpose: EU Directive 97/43 demands for the establishment of national data for dose reference levels in computed tomography. Such a survey for Austria was initiated and supported by the federal authorities (BMSG). Materials and methods: CT dose measurements were performed in 12 hospitals across the country. A total of 369 examinations were recorded. The Weighted Computed Tomography Dose Index (CTDIw) was measured using a PMMA phantom according to the European Guidelines on quality criteria for computed tomography, 1998 (EUR 16262). The scan length for each examination was recorded and the Dose Length Product (DLP) then calculated. Effective doses were derived using conversion coefficients from NRPB-SR250. Results: In general dose reference values (3 rd quartile of CTDIw and DLP) were below the respective reference levels from EUR 16262 mainly due to a closer limitation of the scan intervals. Only CT-examinations of the head showed an increased CTDIw due to increased mAs-values. In comparison with measurements CTDI data either indicated on the console or given in the documents by the manufacturer were equal or slightly greater (up to 20 %) than measured data. Conclusion: For future surveys it seems reasonable to rely on the CTDI-values given by the manufacturers and to collect data on scan parameters and protocols for each examination only.

Assessment of wavelet compression: Comparison of observer performance in microcalcification detection in mammograms and quantitative image quality metrics O. Kocsis, L. Costaridou, L. Varaki, E. Likaki, C.P. Kalogeropoulou, S. Skiadopoulos, C. Dimitroukas, G. Panayiotakis; Patras/GR Purpose: The transmission, storage and display of digitised mammograms require use of image compression. As lossy compression algorithms achieve much higher compression ratios than lossless ones, assessment of "visually lossless" compression thresholds is important. Simultaneously, a major challenge in the adoption of lossy image compression in the medical community is the development of assessment methods using fewer data than ROC analysis. The aim of this study is to determine the visually lossless threshold of a wavelet-based compression algorithm in case of microcalcification detection on mammograms by two methods, observer performance and quantitative compression metrics. Methods and materials: The observer performance study is based on rating of three independent observers, who were blinded to the compression scheme, and evaluated 60 16-bit mammograms for 6 different compression ratios. Quantitative image quality metrics were derived using a set of test objects, digitally created taking into account mammographic image characteristics, for corresponding compression ratios. The proposed metrics, adopted from medical image quality concepts, include high contrast line-pair amplitude modulation, low contrast discrimination, noise, and uniformity. Results: A compression threshold, corresponding to compression ratio 40:1, was found in case of microcalcification detection on mammograms, in the observer performance study. This threshold value was confirmed by the quantitative image quality metrics assessment. Conclusion: Use of the quantitative metrics was proven equivalent to observer study in compression threshold determination. Furthermore, a set of reference values can be specified for the mentioned image quality metrics and used for easy and fast comparative evaluation of different compression schemes.

Contrast enhancement of breast periphery and dense mammary gland in mammography A.P. Stefanoyiannis, L. Costaridou, C.P. Kalogeropoulou, G. Panayiotakis; Patras/GR Purpose: In mammographic imaging, use of high contrast screen-film combinations results in under-and over-exposed film areas corresponding to dense mammary gland and breast periphery, respectively, further characterised by degraded A digital density equalisation technique to deal with the problem of poor visualisation of these regions was designed, developed and quantitatively evaluated.

The technique is based on a layer model of the breast region, in addition to exploiting the film-digitiser characteristic curve. The major steps of the technique are segmentation, to isolate the breast region from mammogram background, and layer density remapping, adapted to the average layer grey level. Quantitative evaluation of the proposed technique was performed on a set of 70 mammograms, based on a contrast index and a proposed equalisation index (standard deviation of the breast region histogram). Results: The proposed technique produced density equalised images, since the decrease in the equalisation index was found to be statistically highly significant (p < 0.0005). Concerning contrast, application of the proposed technique resulted in statistically highly significant contrast improvement (p < 0.0005) for both breast periphery and dense mammary gland. Conclusion: The proposed technique produces density equalised images, characterised by improved contrast of both dense mammary gland and breast periphery. The technique contributes to breast dose minimisation by eliminating the need for a second acquisition.

The development of motion phantom for ECG gated cardiac CT applications M. Imai 1 , Y. Kanzawa 1 , A. Kusaka 1 , M. Kiguchi 1 , K. Miyata 1 , K. Sugimura 1 , N. Sato 2 ; 1 Kobe/JP, 2 Tokyo/JP Purpose: Recently sub-second multislice CT has become available, allowing improved temporal resolution. This may enable application of retrospective ECG gated reconstructions. There are image quality issues related to temporal resolution. Temporal resolution has two elements: (1) motion artifact, and (2) blurring. We developed a motion phantom to analyze them. Methods and materials: There are several factors related to temporal resolution that are assumed to effect image quality: (1) motion faster than available temporal resolution, (2) error between ECG data and actual anatomic motion, (3) interoperation to patch collected row data, (4) helical reconstruction algorithm. The developed motion phantom consists of a motor unit and a phantom object. The phantom is designed to convert the motors' rotation movement to transference. The truck frame and other parts, except phantom object itself, are made from low HU materials similar to the lung. It allows: (1) switch go-and-return movement and transference movement, (2) velocity adjustment (0 -56.5 mm/s), (3) synchronisation with an ECG test pattern, (4) selection of the object phantom with a choice of acrylic sphere and acrylic column. Result: Setting plenary motion with the column object could provoke a typical helical artifact (termed "twister"). It is comparable to the aorta. The extent of blurring could be observed by tuning the phantom motion speed. The sphere object could demonstrate helical artifacts when the object moves along Z direction. Conclusion: The phantom can simulate various human regions that are vibrated by the heart pulse and respiratory motion. It contributes the to analysis of image quality related to motion.

Dose efficient imaging using multi-axial conebeam CT D.J. Heuscher, K. Brown, S. Utrup; Highland Heights, OH/US Purpose: This presentation demonstrates that both excellent image quality and dose-efficiency can be achieved from multi-axial conebeam acquisitions using detector configurations consisting of 16 or more rows. Methods and materials: Both simulated and real successive multi-axial conebeam acquisitions of phantom data were performed using 16 × 1.5 mm and 32 × 0.75 mm detector configurations. These acquisitions were performed with minimal overlap (≤ 6 mm) to provide maximal coverage and dose efficiency. Conebeam reconstructions were performed with a unique filtered-backprojection technique, incorporating a detector aperture function that enables accurate combining of projection data from successive scans. In addition, scans with object motion were performed to assess the effect of the transition between successive acquisitions on image quality. Results: Excellent image quality was achieved using a scan overlap of < 6 mm. Noise uniformity and slice sensitivity (< 1 mm) are both demonstrated. Though a minimal overlap is desired to maximize dose efficiency and coverage, we illustrate the benefits of retaining some overlap between successive acquisitions to minimize the effect of object motion.

We have demonstrated that multi-axial conebeam scans can be performed with excellent coverage, dose efficiency, and image quality. Further investigations are being performed to optimize gated multi-axial acquisitions as used in cardiac applications.

Quantitative evaluation of motion artifact on retrospective ECG gated CT images using an original motion phantom M. Imai 1 , Y. Kanzawa 1 , A. Kusaka 1 , M. Kiguchi 1 , K. Miyata 1 , K. Sugimura 1 , N. Sato 2 ; 1 Kobe/JP, 2 Tokyo/JP Purpose: Recently sub-second multislice CT has become available, allowing improved temporal resolution. Retrospective ECG gated reconstructions may be applied. There are image quality issues related to temporal resolution and no measure of these has been established. We propose some criteria to evaluate motion artifact. Methods and materials: Our phantom allows: (1) adjustment of the velocity, (2) synchronisation with an ECG test pattern, (3) selection of the object phantom. We performed a retrospective ECG gated CT application (Heart View TM ; Volume zoom, Siemens A.G., Germany). We examined these parameters: Moving phantom velocity 0 -56.5 mm/s, uniform velocity or accelerated motion, motion direction, with or without ECG gating, ECG gate timing 0 -120 bpm, and central or peripheral position (200 mm from the centre at most) that we placed the phantom. Other parameters were fixed: 140 kV, 300 mA, 0.5 s/rotation, 1.5 mm table feed/ rotation, 4 × 1 mm collimation, FOV 80 mm. We considered that images have two aspects affected by motion phantom: artifacts and blurring. To evaluate blurring, we measured the profile of phantom in axial and sagittal MPR images that should be rectangular ideally. To evaluate the artifact, we measured the distortion ratio of the oval that should be regular circle. Result: ECG gated images are superior to non-ECG images in terms of both artifact and blurring. The motion along the Z-axis is more infectious than the artifact than across the Z-axis. The peripheral field is more sensitive than the FOV centre. Conclusion: Our study illustrates the effects of motion on image quality. It is also coincident the clinical results.

Exposure indicators in digital radiography: What is their relation to exposure? L. Lehning, S. Günther-Kohfahl, I. Maack, U. Neitzel; Hamburg/DE Purpose: Digital radiography systems use sensitivity (S) or exposure index (EI) values to indicate the detector dose level used for each image. We analysed which factors other than exposure influence the EI value for typical situations. Methods and materials: The study was done on a digital Bucky system with an integrated flat-panel detector (Philips Digital Diagnost). A homogenous water phantom and two anthropomorphic bone phantoms (pelvis, hand) were imaged with systematically varied exposure parameters (dose level, beam quality, field size, object orientation and positioning) and the resulting variations in the exposure index were recorded. In a second study, data from routine clinical use of the system were statistically analysed for the same type of examinations. Results: If all other parameters are fixed the EI is strictly proportional to the applied detector exposure. Changes in collimation and positioning may result in changes of the EI which reach or even exceed 50 %. In the clinical study a characteristic difference was found between free and phototimed exposures. Whereas for the pelvis exposures (with phototiming) deviations in the EI are typically ±20 %, for the hand exposures with fixed mAs the EI may vary by more than a factor 2. The statistical averages for a given examination type were, however, stable over time. Conclusions: Exposure indicators in digital radiography do not only depend on the used level of exposure but reflect also the specific situation of each individual examination. Comparisons to screen/film sensitivities which are derived from a standardized measuring situation may therefore be misleading.

The Nobel prize centennial C. Gotta, A.E. Buzzi, M.M. Buzzi, S. Ballester; Buenos Aires/AR Purpose: To commemorate the Nobel Prize Centennial. Material and methods: We display a summary of Alfred Nobel's life, work and will as well as biographical sketches of the first six people awarded prizes, with special emphasis on Willhem Konrad Röntgen's discovery of X-rays. Results: We illustrate the circumstances, historical context and contribution of the first Nobel Prize winners in 1901, with an emphasis on physics.

Conclusion: We want to pay tribute to those personalities who started a tradition of excellence in scientific research.

A special z-position/time interpolation algorithm to improve temporal resolution and reduce artifact on ECG gated multislice CT Y. Shen 1 , T.-S. Pan 2 , H. Zhang 3 , P. Ding 3 , J. Yi 3 , K. Chen 3 ; 1 Tokyo/JP, 2 Milwaukee, WI/US, 3 Shanghai/CN Purpose: Multislice CT scanning offers new helical cardiac applications. Multisector reconstrcution algorithms can provide high image quality with improved temporal resolution for ECG gated multisclice CT cardiac imaging. However, in the multi-sector reconstuction algorithm, artifact reduction from sector edge/helical is an important issue. The purpose of this paper is to propose and demonstrate two artifact reduction algorithms for the multi sector reconstruction algorithm. Methods: Helical scan and cine scans were performed with a Multislice CT (GE LightSpeed) on both phantoms and patients using helical pitch of approximately 1.0. In the multi sector reconstruction mode, two interpolation algorithms were proposed and tested, one is using oppositional data (180°), and another one is using 360° data. We have assessed the feasibility of using these interpolation algorithms in helical and cine scan modes. Results: In all phantom and patient studies, the proposed two interpolation algorithms can reduce cardiac artifacts comparison with non-interpolation results. Using a pulsating cardiac phantom, the mean artifact reduction rate of 360° z/time interpolation is 69.8 %, and that of 180° z/time interpolation is 76.6 %. The 360°z /time interpolation algorithm can reduce artifact and noise with some temporal resolution trade-off. The 180° z/time interpolation algorithm can reduce artifact and increase temporal resolution with some noise degradation. Conclusion: Two z/time interpolation algorithm have been propsed for multi-sector reconstruction. It was confirmed 180° z/time interpolation algorithm is best algorithm to reduce artifact and increase temporal resolution from phantom and clinical studies.

C-0749 111 InCl3 bone marrow scintigraphy in patients with malignant tumors Y. Tanabe, Y. Ohuchi, K. Sugiura, T. Ogawa; Yonago/JP Purpose: It is important to know the state of bone marrow activity for the management of patients with some malignant tumors. 111 InCl3 has been used for this purpose and its usefulness for determining hematopoietic bone marrow has been reported. 111 InCl3, however, may accumulate in tumors, as it was initially introduced as a tumor-localizing agent. The aim of this study is to re-evaluate the reliability of tumor localization and to determine the problems in evaluating the state of the bone marrow by using of 111 InCl3 in patients with malignant tumors. Material and methods: We retrospectively reviewed 133 111 InCl3 bone marrow scans performed between 1991 and 2000. 6 patients underwent an 111 InCl3 study to determine the distribution of hematopoietic marrow in association with treatment for malignant tumors and were enrolled in this study. Whole-body images obtained 48 h after intravenous administration of 74 MBq of 111 InCl3 were evaluated. Results: In one patient with lung cancer and a malignant pleural effusion, 111 InCl3 did not localise in the tumor. 111 InCl3 showed focal accumulation in the tumors in the remaining 5 patients (1 lung cancer, 2 malignant lymphomas, 1 plasmacytoma, 1 breast cancer). Three of 111 InCl3-positive patients also underwent 67 Ga study, which more accurately defined the lesions than 111 InCl3 did. The high activity in the tumors of 111 InCl3 superimposed on the bone marrow confused the interpretation of the bone marrow function. In a patient with bone metastases to limbs from breast cancer, 111 InCl3 concentrated in the metastases, but the appearance was similar to a "peripheral expansion" of hematopoietic marrow usually seen in central marrow failure. Conclusions: There is no consistency in the concentration of 111 InCl3 in tumor and 111 InCl3 is considered less reliable for tumor localization. As for the assessment of the bone marrow function by use of 111 InCl3 for patients with malignant tumor, it should be taken into consideration that the tumor accumulation of 111 InCl3 may prevent the precise interpretation of the bone marrow reserve. The localization of 111 InCl3 in a primary tumor is unreliable. The uptake of 111 InCl3 in tumors, both primary and metastatic, means that this radiopharmaceutical is unreliable in demonstrating bone marrow reserve.

Computed radiography system: Artefacts and remedies T. Luminati, E. Tagliafico, P. Bartoletti, S. Rombj, C. Frola; Genova/IT Purpose: Computed radiography system may produce artefacts that differ from those of conventional radiography and can cause diagnostic errors. The aim of this presentation is to identify and classify these artefacts in order to reduce or eliminate them when possible. Materials and methods: A computed radiography ADC Compact (Agfa-Gevaert) was installed in January 1999 at our radiological department; images acquired from February 1999 to February 2000 were evaluated for image quality; during this trial a number of artefacts have been identified. Results: Artefacts were classified in four groups:

• Imaging plate artefacts; artefact cause: cracks; artefact remedy: imaging plate must be replaced. • Plate reader artefacts; artefact cause: incomplete erasure, dirt in the light guide; artefact remedy: select the correct erasure setting, clean the light guide of the photomultiplier tube. • Image processing artefacts; artefact cause: improper parameter selection, use of complete automatic processing mode, improper selection of frequency enhancement factors; artefact remedy: post processing. • Operator's errors; artefact: awareness of the artefacts; artefact remedy: protect cassettes from heat, low humidity, scattered radiation; chose correct grid frequency; correct cassette orientation. Conclusions: Artefacts found on digital images are different compared with those found in conventional radiography. The task of radiographers is to reduce the number of artefacts with correct and periodic maintenance of the computed radiography systems. Although this study has been limited to only one vendor's equipment, almost all the artefacts found can currently occur on all the computed digital systems on the market. The risk of a lower extremity deep venous thrombosis (DVT) after trauma is high. The aim of this study was to evaluate the incidence of DVT after bullet wounds. Materials and methods: 19 patients were examined by Color Doppler Ultrasound (Acuson 128/XP-10, Acuson Sequoia-512). There were two groups: 22 patients (all men; age from 22 to 58 year) with trauma of a lower extremity; and 9 patients (all men; age from 20 to 34 year) with bullet wounds of the lower extremity. Patients were examined in a period from one to four months after trauma or bullet wounds. Results: Patients with trauma of a lower extremity: DVT was detected in 8 patients (36.4 %). There was one femoral-popliteal, two popliteal and five calf DVTs. Three DVTs were partially occlusive (two popliteal DVTs and the one femoral-popliteal DVT and the five calf DVTs were occlusive. Patients with bullet wounds of the lower extremity: DVT was detected in 7 patients (77.8 %). There were two popliteal and five calf DVTs. Four DVTs were partially occlusive (two popliteal and two calf DVTs) and three calf DVTs were occlusive. One patient had symptoms of lymphatic edema. Conclusion: The incidence of DVT after bullet wounds is higher than after trauma of the lower extremity. Color Doppler Ultrasound examination should be used in all patients with trauma and bullet wounds for the diagnosis of lower extremity DVT to enable more effective therapy and reduce the incidence of pulmonary thromboembolism.

Evaluation of embolic source of pulmonary thromboembolism: Deep vein thrombosis of MR venography T. Hoshi, T. Kanauchi, T. Hachiya, M. Kanazawa; Saitama/JP Purpose: MR venography (MRV) is useful for the diagnosis of deep vein thrombosis (DVT). We evaluated the lower extremity veins as the embolic source of pulmonary thromboembolism (PTE) using MRV. We also investigated the origin location of pulmonary emboli. Materials and methods: 28 patients with PTE confirmed by enhanced chest CT underwent MRV of the lower extremity. 2D-TOF was used in the pelvis and thigh, and Gd-enhanced MRV with 3-phase dynamic studies were used in the calves. The most proximal localization of DVT was evaluated and the relationship between the proximal site of DVT and the severity of PTE was investigated. Results: Thrombus in the lower extremity veins was found in 26 patients (93 %). Thrombus was localized only in the calf in 13 patients (46 %). Five patients had only intramuscular thrombus. Conclusion: In clinical cases the source of pulmonary thromboembolism was detected in only 50 -70 % of cases because thrombus within the calf veins was not easily diagnosed. MRV was a very useful method to evaluate DVT. We could detect lower extremity thrombus in 93 % patients with PTE by MRV. Gd-enhanced MRV was especially effective for the examination of the calf veins. Almost half of the patients had thrombus only in the calf. Severe PTE may occur in patients with only intramuscular vein thombus. We emphasize the importance of calf vein thrombi, especially the intramuscular veins. MRV is very useful to diagnose the source of PTE.

3D time-of-flight intracranial MR-venography with a small amount of contrast medium administration at 0.5 T MRI T. Ideguchi 1 , T. Muranaka 1 , M. Yonemura 2 , Y. Kawaji 1 , M. Zaizen 1 , H. Ikeda 1 , K. Morimoto 1 , K. Yasumori 1 ; 1 Fukuoka/JP, 2 Kumamoto/JP Objective: The purpose of this study was to determine the volume of contrast medium sufficient for three-dimensional (3D) time-of-flight (TOF) MR-Venography (MRV) of the intracranial venous system. Materials and methods: The 3D-TOF MRV was performed with contrast medium (Gd-DTPA: 0 ml, 5 ml, 15 ml) on 20 subjects. With the 3D-TOF sequence, postprocessing maximum intensity projection (MIP) images were constructed throughout the entire imaging volume. Visual evaluation of the five stages by five radiologists with at least three years experience was performed in respect to the independence of contrast medium volume from the suppression effect of arteries and visualization of the deep cerebral veins.

The deep cerebral veins and transverse sinus were not clearly visualized on 3D-TOF MRV without contrast medium. "Excellent" and "good" evaluations were seen in 72 % in terms of the suppression effect of the artery in the group administrated 5 ml. This rate was significantly a higher than the 33 % in the group administrated 15 ml. "Excellent" and "good" evaluations account for 68 % in terms of visualization of the deep cerebral veins in the 5 ml group, a significantly higher rate than the 44 % in the 15 ml group. In the examination of contrast medium volume independence in an identical case, the artery suppression effect occurred at a rate of 100 % in the comparison of 5 ml administration with 15 ml administration. Conclusion: In conclusion, when carried out with a small amount of contrast medium (about 5 ml), 3D-TOF MRV was useful for demonstrating the intracranial venous system.

Aorto-enteric fistula; an important sign of evaluation with dual-phase spiral CT: The extravasation of contrast medium (10 cases) R. Nicoletti, S. Tacchini, P. Brambilla, L. Brasca, F. De Cobelli, A. Del Maschio; Milan/IT Purpose: To determine the usefulness of dual-phase spiral CT in detecting aortoenteric fistula (AEF). Materials and methods: 10 patients who underwent aortic surgery with graft placement (10 years to 4 weeks previously) with a clinical suspicion of perigraft infection (PGI) and/or AEF were evaluated with spiral CT. In all cases spiral CT examinations (Philips Tomoscan AV) were performed without oral contrast media before, 30 and 90 seconds after intravenous contrast media injection (150 ml Ultravist 370; flow rate 3.5 ml/s) with 3 mm slices and a pitch of 2. CT findings were correlated with surgical reports in all cases. Results: At surgery, all patients had graft infection and a fistula between the superior graft anastomosis and duodenum. At CT examination, in all the 10 cases, the well-known signs of AEF (perigraft fluid collection, perigraft air, soft tissue attenuation around the graft or bowel wall tickening) were shown. Moreover, in six patients with acute gastro-intestinal bleeding and anemia, direct extravasation of contrast medium from the aortic graft into small bowel was detected at CT, whereas in the other four patients with clinical and laboratory signs of sepsis, no signs of contrast extravasation were evident. Conclusion: This study confirms the accuracy of CT in the diagnosis of AEF. In particular, in our experience, at dual-phase CT, extravasation of contrast medium was evident in all patients with gastro-intestinal bleeding.

Painful aortic aneurysms A. Hernigou, C. Grataloup-Oriez, E. Mousseaux, D. Samama, M.-P. Revel, I. Khettab, G. Frija; Paris/FR Purpose: To review patterns of ruptured aneurysms and of "high risk" aneurysms with signs of impending rupture. Material and methods: 50 CT studies (pre and post contrast images) performed in symptomatic patients with aortic aneurysms were retrospectively reviewed with special attention to wall, thrombus and perianeurysmal fat modification. Results: Four different situations were encountered:

• An extraluminal hematoma or perianeurysmal fat infiltration indicating a contained rupture which has to be recognized before cataclysmic rupture. • Aneurysms with signs of impending rupture defined by an abnormal increase in diameter or by partial modifications such as an eccentric lumen, focal discontinuity of circumferential calcification or osteophyte with aneurysmal wall thinning. But the main patterns seen were signs of partial hemorrage with a high attenuation crescent sign in the aortic wall and precontrast hyperdensity inside the thrombus. Such signs are not always obvious and comparison with previous examinations may be helpful. • Infected aneurysms with a high rate of rupture, frequently associated with penetrating ulcers or with spondylodiscitis and sacroiliitis. • CT can also help in relating pain to another cause such as perianeurysmal fibrosis in which rupture is rare or a contiguous lesion independant of the aneurysm. Conclusion: Imaging provides information about aneurysm evolution and knowledge of the CT signs indicating aneurysm complications which allows early repair and prevents true rupture. Purpose: In our study we try to underline the increasing role of interventional radiology in the management of life-threatening, massive gastrointestinal bleeding in which surgical intervention presents a high level of risk. Methods and materials: During the last 12 months we examined 10 patients (6 females, 4 males, mean age 51.7 a) with massive bleeding at different sites: stomach, duodenum, small bowel and colon. We performed three vessel (celiac artery, superior mesenteric artery, inferior mesenteric artery) selective diagnostic angiography in every patient as an emergency. The site of the bleeding was accurately established from the left gastric artery territory in 2 cases, gastroduodenal artery in 2 cases, jejunal branches of the superior mesenteric artery in 4 cases, ileocolic artery in 1 case and left colic artery in 1 case. After that, TAE was performed with an emulsion of particles (0.5 -1 mm, according with the amount of bleeding and with the dimensions of the vessels) of Tachocomb and Gelaspon, mixed with contrast medium. Results: For all patients the bleeding was stopped promptly, after the procedure angiography showed the occlusion of the vessels involved in the bleeding, and very importantly the preservation of collateral branches. After TAE we noticed a rapid improvement in the clinical symptoms and laboratory parameters. No patient required a surgical procedure. Conclusions: TAE used in gastrointestinal bleeding sometimes represents the only choice for patients with a high surgical risk.

Single-slice CT angiography vs multi-slice CT angiography in patients undergoing endovascular repair of abdominal aortic aneurysm R. Iezzi, R. Fossaceca, M. Salcuni, L. Salute, L. Bonomo; Chieti/IT Objective: To compare single-slice CTA (SS-CTA) and multi-slice CTA (MS-CTA) in the pre-operative assessment of patients undergoing endovascular repair of abdominal aortic aneurysm (AAA). Materials and methods: From June 1998 to August 2001, 52 patients with AAA underwent treatment with a bifurcated stent graft. 29 patients were studied with SS-CTA (3 mm collimation, pitch 2, and 2 mm reconstruction increment; scan duration 45 s) whereas 23 patients were studied with MS-CTA (4 × 1 mm collimation, pitch 6, 1.25 mm slice width, and 1 mm reconstruction increment; scan duration 25 s). Axial images and 3D reconstructions were evaluated for aneurysm diameter, characteristic of the neck and patency of aortic side branches including the inferior mesenteric, lumbar and hypogastric arteries. The presence of calcification and thrombus was also considered. CTA findings were compared with intraoperative DSA findings. Results: SS-CTA allowed visualizazion of 10 accessories renal arteries, 2 stenotic renal arteries, 2 renal arteries with ostial calcification without stenosis, and 43 lumbar arteries. MS-CTA allowed visualization of 7 accessory renal arteries, 5 stenotic renal arteries, and 48 lumbar arteries. These findings were all confirmed by intraoperative DSA. Conclusions: Although MS-CTA reduces scan time and improves reconstruction quality, no statistically significant differences were found between the accuracy of the two techniques.

Diagnostic and therapeutic use of gadolinium-DOTA enhanced DSA in renal insufficiency patients F. Boudghène, M. Tassart, J.-F. Deux, O. Geoffroy, S. DeGivry, A. LeBlanche; Paris/FR Gadolinium chelates have proved to be safe, well-tolerated and effective contrast agents, and have been assessed as less nephrotoxic than iodinated contrast agents. In patients with renal insufficiency, intravenous injection of gadolinium chelates does not show any evidence of nephrotoxicity during MR imaging even with large doses (0.4 mmol/kg). Since 1989, gadolinium chelates have been used in patients with renal insufficiency as an alternative X-ray contrast agent for digital substraction angiography (DSA) and has also been proposed for various other types of interventional procedures. We report our experience of 110 patients where Gd-DOTA DSA was used for vascular opacification in procedures relating to end-stage renal disease: 69 upper extremity DSA venography, 23 DSA fistulography, and 18 renal artery angioplasty.

Gd-DOTA DSA examinations proved to be effective and safe in routine practice in cases of renal insufficiency to plan arteriovenous fistula (AVF) creation and to assess their malfunction after surgery and to perform percutaneous angioplasty (PTA) of the renal artery or AVF stenosis. In all cases it was associated with preservation of renal function. Learning objectives: (1) Describe the theoretical considerations of the use of Gadolinium chelates as X-ray contrast agents. (2) Detail practical aspects for the realization of Gadolinium DSA in a standard digital vascular room. (3) Report the clinical experience and results of our group in routine practice in renal insufficiency patients. (4) Enhance precautions to observe when using contrast agents in patients with end stage renal disease.

Anomalies of inferior vena cava: A case of retroaortic left renal vein and infrahepatic interruption continuing with azygos-hemiazygos vein A. Basile 1 , R.M. Bouzas-Sierra 2 , S. Lamberto 1 , A. Certo 1 ; 1 Messina/IT, 2 Vigo/ES Purpose: The aim of this report is to describe a rare case of association of Inferior Vena Cava anomalies. These alterations are uncommon and are frequently found in correlation with abnormal abdominal situs, representing a risk for any thoracic or abdominal surgical approach. In these cases preoperative evaluation must be made, to disclose all the alterations of normal anatomic findings and to avoid any inappropriate surgical manoeuvres. Case report: A 46 year old male was admitted with symptomatology suggesting pulmonary thromboembolism. He underwent thoraco-abdomino-pelvic contrast enhanced spiral computed tomography that disclosed thrombosis of the common left Iliac vein continuing cranially with the lumbar plexus to the left renal vein. The CT examination also showed an interruption of the IVC below the hepatic vein continuing centripetally with the azygos and hemiazygos and a retroaortic renal vein. The patient also had double access cavography that confirmed the CT findings. Result: The diagnostic tools disclosed a rare association of anomalies of IVC.

The venous blood flow of the lower portion of the body arises from three pair of embryological vessels (Posterior Cardinal, Sub-Cardinal and Supra-Cardinal) that finally develop the IVC. In our case we disclosed an infrahepatic interruption of IVC continuing with the azygous and hemiazygous veins and a retroaortic left renal vein. This combination of anomalies, due to an incorrect embryological evolution, is rare and suggest complementary examinations to detect other related anatomic alterations to avoid, in the case of abdominal interventions, inappropriate manoeuvres.

Experimental studies of the microangioarchitecture of tumors using synchrotron radiation and microcomputed tomography S. Imai, N. Maehara, Y. Kajihara, T. Yamashita; Kurashiki/JP Purpose: To compare differences in the depiction of small vessels in tumors on microangiograms obtained with a synchrotron radiation (SR) system and by microcomputed tomography (CT), and to evaluate the microangioarchitecture of tumors and the process of their growth neovascularization. Methods and materials: VX2 carcinomas were transplanted into 15 rabbit auricules. One, three and seven days after transplantation, barium contrast material was injected into the auricular artery. Microangiograms of the auricle specimens were obtained with the SR system and micro CT. The SR system consisted of a monochromatic X-ray source of 37.6 keV just above K absorption edge of barium at Spring-8. The CCD system had a 6 µm equivalent pixel size and an input field size of 6 × 6 mm. The CT images were obtained by micro CT (ELESCAN) at a voltage of 35 kV. The field of view was 72 mm × 54 mm and the CCD system had a 28 µm equivalent pixel size. The slice thickness was 22.5 µm with 512 × 512 matrix. Results: Microangiograms using the SR system depicted small vessels with a diameter of less than 25 µm. The microangioarchitecture of the tumor could be evaluated well from micro CT images. The micro CT depicted small vessels with a diameter of less than 50 µm. In addition, it allowed us to confirm the three-dimensional process of growth neovascularization in the tumors. Conclusion: Using a SR system with micro CT may be a useful tool for evaluating the microangioarchitecture of tumors and for clarifying the angiogenesis of tumors.

Hepatic artery aneurysms (HAAs): Role of interventional radiology A.A. Polikarpov, P.G. Tarazov; St. Petersburg/RU Aim: To evaluate effectiveness of interventional radiological treatment of HAAs.

Methods: A retrospective study was carried out in 5 high risk patients with HAAs. In four pts with iatrogenic aneurysm of the right hepatic artery, one was diagnosed after resection of hepatocellular carcinoma, one after liver transplantation (complicated by hemobilia), one after transcatheter embolization of focal nodular hyperplasia and one after transhepatic biliary drainage because of pancreatic carcinoma, complicated by hemobilia. The remaining patient had a true aneurysm of the common hepatic artery. Selective transcatheter arterial embolization using Ivalon/Gelfoam/coils was successfully performed in 4 patients. In one case, when arterial embolization failed, we performed direct transhepatic embolization of the aneurysm using gelatine sponge and thrombin. Results: Follow-up angiography showed occlusion of all 4 intrahepatic aneurysms. Unfortunately, recanalization of the common hepatic artery aneurysm developed after embolization, but displacement of the aneurysmal lumen from the periphery to the center of the HAA was considered to represent a reduction in the risk of spontaneous rupture. Conclusion: An interventional radiology approach is the treatment of choice for intrahepatic HAAs in patients with a high risk for surgery.

XML files for angiographic image transfer V. Saplacan 1 , A. Radulescu 2 , S. Sfrangeu 1 ; 1 Cluj/RO, 2 Oradea/RO Purpose: We considered the XML files the best mode of angiographic image transfer due to the fact that they are portable between different platforms and offer a good way of hierarchical objects. They also can be viewed directly by web browsers.

We use a web-based system to distribute medical images and data relative to the patients. The angiographic images were stored in a multimedia medical database. We used the MSSQL Server 7.0 database server. Images were stored in JPEG format. By mean of different C++ programs we generated XML files for those cases where there was a need for future use of the images in other departments. The XML files are then transferred to their destination where future processing will follow. Results: The images were distributed in 2 ways. The primary mode of image distribution was the XML files transfer between computers in our hospital network. The XML file was then used differently considering the future use and platform on which the file will be used. We also published the images on a web server, so they could be viewed directly. Conclusion: XML files offer a very low-cost and fast method of transfer of angiographic images and data in a multi-hospital environment.

Artefacts in colour Doppler imaging: A comprehensive illustrated guide F. Sandomenico, O. Catalano, A. Nunziata, A. Siani; Naples/IT Purpose: To offer an illustrated guide to the appearance, cause, and practical meaning of the most commonly encountered artefacts in colour and power Doppler imaging. Artefacts illustrated: Various false images will be illustrated: aliasing artefact, pseudoabsent flow image ("back shadowing"), mirror artefact ("ghost vessel"), overflow image ("bleeding"), peristenotic tissue vibration artefact, and twinkling artefact. The basis and meaning of these findings will be explained and the optimised scanner setting to eliminate these artefacts will be illustrated. Circumstances in which artefact detection is helpful will be depicted.

Material and methods: 30 consecutive patients were examined on a 1.5 T whole body system (gradient field strength 30 mT). 3D TOF MRA (voxel size: 0.4 × 0.8 × 1.0 mm) was applied for dedicated visualization of the extracranial carotid bifurcation. CE-MRA (3D FLASH sequence, coronal orientation, voxel size 0.6 × 1.2 × 0.8 mm) with elliptical centric k-space order was used to image the whole vasculature from the aortic arch up to the circle of Willis. Evaluation of stenoses was done in steps of 10 % and attributed to four grades. Results: Concerning stenoses of grade 3 -4 of the internal and external carotid arteries, good agreement between MRA and selective X-ray angiography was found. 3D TOF MRA was slightly superior to CE MRA when analyzing the carotid bifurcation stenoses in steps of 10 %. This is probably due to the improved spatial resolution of 3D TOF in comparison to CE-MRA. MRA revealed excellent values concerning the detection of high grade stenoses at the level of the extracranial bifurcation (sensitivity 96 -100 %, specificity 100 %). Conclusion: The combination of high-resolution 3D TOF MRA and CE MRA yields excellent results for detection of carotid arterial stenosis in comparison to selective X-ray angiography and may therefore become a non-invasive alternative to invasive X-ray angiography.

CT angiography in the diagnosis of brain aneurysms A. Zapasnik 1 , A. Urbanik 2 , R. Chrzan 2 , H. Pacoszynska-Zapasnik 3 ; 1 Gdansk/PL, 2 Krakow/PL, 3 Gdynia/PL Purpose: The aim of the study was to demonstrate the application of CT angiography (CTa) with 3D reconstruction and virtual angiography (VA) in the evaluation of the aneurysmal sack and neck before and after neurosurgical or endovascular procedures. Material and methods: CT angio of the brain vessels was performed in 90 patients. The parameters of the study were: slice thickness 1 mm, pitch 1, increment 30 %, examination extend 30 mm. 100 -150 ml of contrast medium were injected (4 ml/s) after a delay of 20 s. The image data of 30 patients was selected and analysed using Endo (Marconi) and Navigator (GEMS) original software. The operative findings were compared to 3D images and images obtained from virtual angioscopy. Results: The architecture of the internal and the external structure of the sack and neck of the aneurysm were correctly estimated. An indication of the exact place of rupture, in the case of bleeding aneurysms, was possible using virtual endoscopy in 10 patients -proven by operation reports. The evaluation of post-operative results in patients with surgical clips or with embolized coils is more clear and precise in angio-CT. Conclusions: Angio-CT is a valuble method of recognising the origin of subarachnoid bleeding, and above all, no matter what the clinical state of the patient is, it is a fully safe, valuable diagnostic method imaging brain aneurysms.

The role of ultrasonography in detecting and monitoring the effects of pharmacological treatment in Takayasu's arteritis J. Pienkowska, A. Zapasnik, E. Szurowska, G. Luszczynska-Nitka; Gdansk/PL The aim of the study was to present ultrasonographic findings of the cervical and sublavian arteries in patients with Takayasu's arteritis before and after corticosteroid treatment. We used B mode and colour duplex sonography to study the arteries in the neck including the common carotid artery (CCA), internal carotid artery, external carotid artery, vertebral artery and the subclavian arteries. Ten female patients fulfilling the clinical diagnostic criteria for Takayasu's arteritis were studied. The characteristic vascular lesions such a homogeneous, concentric intima and media thickening resulting in narrowing of the vessel lumen and the effects of the therapy were analyzed. All the studied patients had subclavian artery involvement with diffuse, homogeneous, concentric vessel wall thickening. Four patients also had bilateral CCA involvement and three had unilateral CCA involvement. The increased thickness of the arterial wall in patients with Takayasu's arteritis resulted mainly from intima and media thickening. In our group intima and media thicknesses were from 0.23 to 0.4 cm for the subclavian and from 0.3 to 0.48 cm for carotid arteries. Duplex ultrasound revealed long-segment stenosis and showed increased blood velocity of the involved vessels. During pharmacological treatment a symptomatic decrease in the intima and media thickenesses from 0.1 to 0.2 cm for subclavian arteries and from 0.17 to 0.35 cm for CCA, with a partial decrease of blood velocity, were observed. Ultrasonography could be used as a simple, safe and noninvasive procedure in patients with Takayasu's arteritis not only to detect wall thickening and luminal stenosis, but also to monitor the effects of pharmacological treatment.

Imaging of blood vessels before and after dialysis fistula creation R. Pietura, A. Szymanska, M. Szczerbo-Trojanowska; Lublin/PL The aim of the study was to present our own experience in imaging immature fistulas and blood vessels before creating hemodialysis access. Colour duplex sonography (CDS) was performed in 25 patients before creating their first hemodialysis fistula (group I) and in 80 patients with "immature" fistulas (group II). In group I, diameter and flow parameters during a compression test in arteries and veins of the upper limb were evaluated. In group II, diameter and flow parameters at the anastomosis and the arterial and venous branches of the fistula were assessed. 49 immature fistulas presented with clinical symptoms of failure. Angiographic evaluation of the veins in the upper limb, subclavian and brachiocephalic veins was performed in 52 patients (48 before creation of the next fistula and 4 with dubious US findings). In patients from group I CDS showed normal vessels in 17 and in 4 patients abnormal vessels. In 29 patients from group II CDS allowed us to draw the course of vein on the skin in order to help a nurse locate it. Among 49 patients from group II, 9 total occlusions, 8 hematomas, 5 chronic thromboses, 1 abscess and 1 fluid collection close to anastomosis were demonstrated. In 52 patients angiography showed all patent veins of the upper limb. Pathology of the central veins was demonstrated in 18 patients. Colour duplex sonography and angiography are useful in evaluation of blood vessels before creating vascular access. Phlebography is the method of choice in imaging subclavian and brachiocephalic veins. Colour duplex sonography allows early detection of lesions which lead to fistula failure.

Gadolinium enhanced 3D angiography in the postoperative assessment of cavo-pulmonary connections M. Jiménez, V. Martinez de Vega, M. Lopez-Pino, J. Montoya, M. Recio, J. Viaño; Madrid/ES Purpose: Cavo-pulmonary shunts are performed in patients with a single functioning ventricle. Two steps are performed: first, the Glenn procedure (superior vena cava and right pulmonary artery connection) and second, the Fontan technique (inferior vena cava and pulmonary artery connection). Postoperative studies must include the correct evaluation of the shunt and the broncho-pulmonary tree. Our aim is to show our initial experience in the postoperative evaluation of such patients with gadolinium enhanced MR angiography. Material and method: 15 paediatric patients (12 with a Glenn procedure and 3 with extracardiac duct and Fontan procedures) were examined and compared with sonographic and conventional angiographic findings. These studies were made in a 1.5 T MR (GE System) with double dose gadolinium enhanced 3DFSPGR sequences. Multiplanar reformations, maximum intensity projections (MIP) and 3D volumetric reconstructions were obtained. Results: Gadolinium enhanced MR angiography allows the measurement of the postoperative connection area between the superior vena cava and right pulmonary artery and the peripheral and central diameter of the pulmonary arteries. 4 focal stenosis in a pulmonary arterial branch, assessed by conventional angiography, were detected. The connection ducts between the pulmonary artery and the inferior vena cava were correctly visualized. Discussion and conclusion: MR angiography offers a complete anatomical evaluation of the cavo-pulmonary shunts and pulmonary arteries. MR imaging is an accurate, non-invasive method in the postoperative evaluation of these patients.

Helical-CT role in the identification of Adamkiewikz artery in pre-treatment evaluation of patients with thoracic aneurysms M. Natrella, M. Sacco, S. Baldi, P. Oronzo, M. Alessi, A.R. Cotroneo; Novara/IT Purpose: The anterior spinal artery (ASA) receives 2 or 3 branches from the aorta of which the most frequently seen is the Adamkiewikz artery (AA). The aim of our study was to determine the accuracy of angio-CT in the evaluation of the ASA and AA for endoprosthesis positioning in thoracic aneurysms. Material and methods: Between December 2000 and July 2001 we studied 6 patients with a dedicated protocol before positioning endoprosthesis, 5 patients with thoracic aneurysms and 1 with aorta coarctation. The dedicated protocol was performed with Hi Speed CT/i GE (slice thickess 3 mm, reconstruction interval 1.5 and pitch 1.5). The acquisition volume started from the aortic arch and ended at the celiac trunk; scanning was initiated during intravenous injection of 180 ml of iodinated contrast at 5 ml/s timing the start of the acquisition by means of a bolus track technique. The data obtained was reconstructed using sagittal and coronal planes in order to identify the ASA and AA.

Spiral CT evaluation of the pulmonary vessels: Injection biphasic protocol

Conclusions: MRI assists in the precise evaluation of the lesions associated with the neurofibromatoses. This modality and to a lesser extent CT, aids the radiologist to distinguish benign and malignant features of this disease.

Intracranial manifestations of cervicocephalic fibromuscular dysplasia (FMD) C. Gaebel, S. Gottschalk, U. Missler, J. Sperner, D. Petersen; Lübeck/DE Purpose: Pathologies of the intracranial vasculature in patients with FMD are rare and have hitherto been described only casuistically. Methods and material: Twelve patients with intracranial FMD manifestations were examined by CCT, MRI, Doppler, TOF-/CE-MRA and catheter angiography. One case was verified at autopsy by light-/electronmicroscopy and immunohistochemistry. Results: In eleven patients the diagnosis of FMD was based on the catheter angiographical detection of the pathognomonic string of beads-sign at the midportion of the cervical ACI. In one case with solely dilatative manifestations the diagnosis was achiveable only at autopsy. Seven patients presented with infarctions from ipsilateral stenosis at the terminal carotid bifurcation and/or the M1-segment. All stenosis were equally demonstrable by MRA and catheter angiography. In the three children with stenoocclusive manifestations the MRA follow up revealed changes of stenosis morphology. This served as an indication for catheter angiography, which detected hitherto unknown slight string of beads-signs at the cervical ACI. Five patients presented with subarachnoid hemorrhages from multiple aneurysms. One of these patients additionally suffered from a large AV-Angioma. Conclusion: FMD can be accompanied by a broad spectrum of stenoocclusive and/or dilatative findings at the intracranial vasculature. For the detection of small string of beads-changes a catheter angiogram is mandatory, whereas intracranial stenosis are equally detectable by combining TOF-and CE-MRA. In cases of stenoocclusion of unknown cause any dynamic of stenosis morphology at MRA follow-up should indicate a catheter angiography. The spectrum of cervicocephalic FMD includes solely dilatative manifestations, which might only be accurately diagnosed by histological criteria. Conclusion: Ultrasonography is currently used in combination with ophthalmological examination to achieve the diagnosis of intraocular tumors. Intraocular biopsy is seldom performed. It is good at demonstrating the nature of the tumor (solid or cystic, homogeneous or heterogeneous) and to define its size. CT imaging is indicated when extraocular involvement is suspected. Choroidal melanoma can reach the orbit by perforating the globe and retinoblastoma can enter the central nervous system by extension to the optical nerve. MRI is rarely requested as it does not add any further information when compared with CT imaging, except in choroidal hemangioma where differential diagnosis from choroidal melanoma can be made.

The clinical value of 123 I-MIBG scintigraphy in patients with neuroblastoma detected by a mass screening survey T. Hashimoto 1 , K. Koizumi 2 , T. Nishina 2 , A. Yamazaki 2 , K. Saito 1 , F. Kotake 1 , K. Abe 2 ; 1 Ibaraki/JP, 2 Tokyo/JP Purpose: To evaluate the clinical value of 123 I-MIBG scintigraphy with both planar images and SPECT for 33 patients with neuroblastoma detected by a mass screening survey. Materials and method: 123 I-MIBG planar images of 33 patients including 56 abdominal SPECTstudies were reviewed. All patients were detected by a mass screening survey of vanillymandelic acid (VMA) levels performed at 6 months of age. Additionally, the patients in this study underwent surgery for neuroblastoma. Imaging using 111 MBq of 123 I-MIBG was performed 24 hours after injection. The accuracy of planar imaging in demonstrating the extent of the lesion and whether the degree of uptake and area of the lesion accumulating 123 I-MIBG correlated with the surgical findings and tumour markers, such as VMA, HVA, NSE, and LDH was assessed. Additionally, we evaluated the clinical usefulness of SPECT compared to planar images. Results: The 123 I-MIBG planar images revealed all 33 (100 %) primary lesions, 4 of the 5 cases (80 %) with liver metastasis, 3 of the 13 (23 %) with lymph nodes metastases, and 1 of 3 (33 %) with bone marrow infiltration. The area and degree of accumulation correlated with elevated levels of VMA, HVA, and NSE (but not with LDH and clinical staging). SPECT images added anatomical information all cases, provided useful additional information in 7 cases, but were misleading in 3 cases. Conclusion: 123 I-MIBG scintigraphy, using planar images and SPECT is useful for evaluating patients with neuroblastoma identified by a mass screening survey.

A survey of paediatric CT dose reduction practice in the UK S. Yusuf, S. Chapman, K. Johnson; Birmingham/GB Introduction: There has been some controversy recently regarding paediatric radiation doses during CT investigations. In children it is important to minimise radiation doses, but without compromising image quality. The aim of this study is to ascertain the current UK practice in paediatric CT imaging, and see if there is any attempt to minimise radiation dose. Method: A telephone survey of UK radiology departments was performed. Each department was questioned regarding paediatric exposures and any alterations that were made in standard practice when imaging children. Results: 67 hospitals were contacted throughout the UK. 11 hospitals did not perform paediatric imaging. 2 hospitals made no alteration to exposure parameters for children. 54 hospitals altered the exposure parameters for paediatric brain imaging, and 43 departments followed a strict protocol. One department used automatic calibration. Only 4 departments had a separate lower dose protocol for investigating children with potentially blocked intraventricular shunts. 28 hospitals performed paediatric body imaging; 17 departments followed a set protocol. 3 departments used automatic calibration. Conclusion: These results demonstrate that there is awareness of the need to decrease the radiation dose when imaging the paediatric population, whilst still producing images of an adequate diagnostic standard. There is marked variation in exposure parameters throughout the country, but other variables, including the type of scanner, size of patient and the clinical context of the scan, need to be taken into account. There is a need for both equipment manufacturers and radiology departments to optimise paediatric imaging facilities.

Pre-and postoperative magnetic resonance imaging in paediatric oesophageal and gastric leiomyomatosis A.K. Kilian, K.W. Neff, T. Ringle, K.L. Waag, C. Düber; Mannheim/DE Introduction: Oesophageal leiomyomatosis is a very rare benign tumour, which may be associated with leiomyomas in other locations or with other disorders (Alport syndrome). Until now, the most common diagnostic procedures for the detection of oesophageal leiomyomatosis are barium studies, ultrasonography (US) and computed tomography. In children, beside US, magnetic resonance imaging (MRI) Neuro A Purpose: To optimise a biphasic protocol for administering contrast quality of the imaging in the study of the pulmonary vessels reducing the amount of contrast material with saline solution. Materials and methods: 30 patients suspected of pulmonary embolism have been studied with spiral CT; the patients were assigned randomly into one of two categories: (a) injection of 120 ml of non ionic contrast material alone (300 mg iodine per milliliter, 15 patients) the injection rate was 2.5 ml/s. (b) injection of 90 ml of contrast material pushed with 30 ml of saline (15 patients). In both group the injection rate was 2.5 ml/s with biphasic method. In this group an initial speed of 1.5 ml/s has been used for 30 s followed by a second phase to 2.5 ml/s for 35 s. Acquisition of images started 45 s after the beginning of injection. All patients were scanned in a caudal-to-cranial direction. The images have been appraised and judged by the quality of opacification of the vessels and reduced artefacts from dense contrast material in the SVC, aorta and heart. Results: Contrast enhancement of the peripheral and central pulmonary arteries were excellent with the biphasic method in comparison to traditional protocol. Pulmonary veins have also been enhanced better in the biphasic method and artefacts are significantly less evident in the biphasic protocol. Conclusions: A biphasic technique with saline solution helps to decrease the amount of contrast material, and improves image quality of pulmonary vessels.

Dosimetry of the skin dose in interventional radiological procedures: How to improve the patient's management L. Corkovic; Osijek/HR Purpose: Measurement of the skin dose by simulation on the angiographic equipment "Shimadzu" Digitex 2400 (Japan) using similar conditions which exist when performing interventional radiological procedures. Materials and methods: A phantom made of 260 mm thick polystyrene (hard, transparent, thermoplastic synthetic resin) was used as a model for skin dose measurement. Dosimetry measurements of such phantom and water have been shown to be reliable. An ionization chamber (type 23342, serial number 1280, calibrated in German National Laboratory, PTB Braun Schweig) was placed inside the phantom and connected to the electrometer Unidos, PTW Freiburg. Parameters such as source-to-skin distance (SSD), air gap and field of view (FOV) were changed during automatic continuous fluoroscopy. Results: A reduced SSD, increased air gap and decreased FOV significantly increase patient skin dose. Conclusions: Continuously increasing radiological work loads in radiology departments and particularly increasing complicated interventional procedures, require increased attention to personal and patient safety. Familiarity with the effect of alteration in SSD, air gap and FOV will result in significantly lower patient skin doses.

Artefacts and image distortion on three-dimensional digital subtraction angiography Y. Takei 1 , M. Murata 1 , T. Nomura 2 , H. Narita 1 , H. Sakahara 1 ; 1 Hamamatsu/JP, 2 Kanazawa/JP Purpose: To evaluate artefacts and image distortion on three-dimensional digital subtraction angiography (3D-DSA: Advantx LCN plus, GE Medical Systems).

We placed a small spherical phantom made of acrylic at one of 15 points in the three-dimensional (3D) space of view and performed 3D-DSA for each and every point. Also we placed a stick phantom in the horizontal, vertical, or oblique orientation to the rotational axis and ran 3D-DSA also for each position. After acquisition, data were transferred to a workstation (Advantage Workstation 3.1, GE Medical Systems). 3D images were generated with two different reconstruction algorithms and displayed in maximum intensity projection (MIP) format and in shaded surface display (SSD). Artefacts and image distortion on these 3D images were evaluated. Result: With the spherical phantom, we did not observe any image distortion on any point in the 3D space of view. With the stick phantom, we saw a strong image distortion in every one of the three orientations. The strongest distortion was observed with the stick phantom in the oblique orientation. Spatial distribution of artefacts was different between the two reconstruction algorithms. With narrower collimation of the coned beam of X-rays, a part of artefacts disappeared.

With a spherical phantom, no image distortion was generated. With the stick phantom, a strong image distortion was observed. One of the causative factors of artefacts could be the scatter of X-ray beam.

Utility of multidetector CT angiography using a dual-head power injector: Application to aortic diseases N. Hirai, S. Imakita, R. Tanaka, M. Higashi, Y. Hori, K. Kimura; Osaka/JP Purpose: Our goal was to establish the utility of multidetector CT angiography using a dual-head power injector for evaluating aortic diseases. Materials and methods: 27 patients with aortic disease were examined by multidetector CT. Seventeen of 27 patients were examined with an electricallyinterconnected dual-head power injector (dual-head group) and the others were examined with a single-head power injector (single-head group). Intravenous injection was performed via the right antecubital vein at a rate of 1.5 ml/s. Scanning was performed from lung apex to the inguinal region using "Real prep helical scanning", triggered at the ascending aorta over 120 HU. In the dual-head group, 0.6 ml/kg body weight (mean 37.2 ml) of contrast medium (350 mg I/ml) was injected; immediately followed by a flush of 30 ml of saline solution. In the singlehead group, 1.0 ml/kg body weight (mean 66.5 ml) of contrast medium was injected without saline flush. We compared the CT values at the level of celiac trunk, aortic bifurcation and bilateral common femoral arteries between the two groups. We evaluated the CT angiograms in the characterization of aortic disease. Results: In all cases, good CT angiograms were obtained. In the dual-head group, CT values were 10 -15 HU less than in the single-head group at each evaluated slice. In all cases of the dual-head group, good CT angiograms were obtained despite a 40 % reduction in contrast medium dose. Conclusion: Multidetector CT angiography, using dual-head power injector, is a valuable tool in the diagnosis of aortic disease with a low dose of contrast medium.

Utility of multidetector CT angiography in the diagnosis of arteriosclerosis obliterans R. Tanaka, S. Imakita, N. Hirai, M. Higashi, Y. Hori, K. Kimura; Osaka/JP Purpose: Our goal was to establish the utility of multidetector CT angiography (MD-CTA) for evaluating arterial stenosis in patients with arteriosclerosis obliterans (ASO). Materials and methods: 25 patients with ASO were examined by both MDCT with "Sure start helical scanning" and digital subtraction angiography (DSA) with "stepping" or "bolus chasing". For the arterial survey of the lower limbs with MDCT, we used maximum intensity projection (MIP), conventional volume rendering (C-VR), and "narrow bandwidth volume rendering" (NB-VR) which is a newly devised volume rendering method with double-threshold targeting to the contrast inside vessels and high transparency to avoid partial voluming from high density structures. In addition to axial images, multiplanar reconstructions (MPR) were also used for the evaluation of localized stenoses. We compared MD-CTA with DSA for their characterization of arteries of the lower limbs. Results: In all patients, MD-CTA was superior or equivalent to DSA for their characterization of whole arteries from pelvis to ankle, even in cases with differential arterial flow down the legs. MIP and C-VR could not clearly depict arterial stenosis surrounded by dense calcification or metallic stent, which usually needed DSA evaluation. NB-VR could clearly disclose these lesions. An additional MPR could support these findings. Conclusion: MD-CTA with "Sure start helical scanning" is an effective method in evaluating arterial stenosis. "NB-VR" is a valuable method for accurate diagnosis of arterial occlusive disease with MD-CTA.

Multi-phase three-dimensional gadolinium-enhanced MR angiography in the child K. Hayasaka, Y. Tanaka, M. Takahashi, T. Saitoh; Tokyo/JP Objective: To investigate abdominal tumors and pulmonary sequestration by analyzing multi-phase three dimensional (3D) gadolinium-enhanced abdominal MR angiography (MRA) in the child. Materials and methods: Ten patients with abdominal tumors and pulmonary sequestration were included in this study. Abdominal MRA was performed using a fast contrast-enhanced high resolution 3D technique in ten children who were sedated. Gd-enhanced abdominal MRA was obtained with 3D FISP or 3D FLASH after intravenous gadolinium bolus injection. The 3D images were reviewed by two radiologists, and the evaluation was based on consensus. These images were compared with the surgical findings except one liver hemangioma. We analyzed the quality of the 3D Gd-enhanced MRA images, the vessels of the abdominal aorta, and the hemodynamics of the lesion.

In all cases, good or excellent images were obtained. The major branches of the abdominal aorta were demonstrated in all cases. In the patient with pulmonary sequestration, the supply from the abdominal aorta could be identified. The portal vein and inferior vena cava were identified in all cases. MRA revealed arterial encasement in two patients, and venous invasion in three. MRA showed hypervascularity in lesions of two patients, moderate vascularity in three and hypovascularity in five.

The multi-phase 3D Gd-enhanced abdominal MRA can be applied as an easy, safe and valuable imaging method for the preoperative information of pediatric pathology.

Peripheral MRA: A multiinstitutional consortium analysis in rountine clinical cases -how is it done, how good is it, where are the challenges? M.V. Knopp; Bethesda, MD/US Purpose: Peripheral vascular disease is a major disease entity leading to substantial costs in diagnosis and therapy. While MRA of run-off vessels has been extensively evaluated already in clinical trials, its clinical spectrum of use, utility, success and limitations have not been assessed in a truly multicenter, multi-procedure evaluation. Materials and methods: A multi-institutional group interested in MRA organized itself and decided to focus on peripheral MRA (pMRA). The consortium consists of > 15 institutions from academia, general hospitals and imaging centers and we invited hardware manufactures to participate as advisers. This project is supported by an educational grant for organizational infrastructure. Prospectively, an interactive Web-based database was implemented to enable electronic case documentation. Every site was free to continue their own way of performing pMRA with only standardization of the documentation. The proposed case number of more > 350 will be reached at the end of III quarter of 2001. The database is being monitored and managed by a CRA. Results: While the database is currently not yet closed, diagnostic utility of pMRA was excellent. A wide array of different approaches have been used successfully. This exhibit will present two kinds of analysis, one reviewing the different approaches as categories, the other looking at the disease state and report which approach seems to be preferential. Conclusion: This scientific exhibit will present the findings of a large, multi-institutional study on the clinical uses of peripheral MRA and will summarize how it is done, how good is it in clinical practice and where are the challenges?

Angio-CT vs digital subtraction angiography (DSA) in intracranial aneurysm detection M. Sacco, G. Guzzardi, A. Chieppa, M. Natrella, M. Alessi, A.R. Cotroneo; Novara/IT Purpose: The aim of our study was to determine the accuracy of Spiral Angio-CT in comparison with Digital Subtraction Angiography (DSA) in the evaluation of intracranial aneurysm. Methods and materials: In the period between January 1999 and August 2001 forty patients (25 F and 15 M) with subarachnoid haemorrhage (ESA) underwent Spiral angio-CT and DSA. All CT examinations were performed on a GE Hi Speed Advantage system with elicoidal scansion (slice thickness 1 mm; reconstruction interval 0.5 mm and pitch 1). The acquisition volume was 5 cm from the base of sella turcica after intravenous injection of 120 ml iodinated contrast agent, timing the start of the acquisition with the bolus track technique. Acquired data were then transferred to an independent console to perform angio-CT post processing using Maximum Intensity Projection (MIP) to obtain images comparable with digital angiography. Results: DSA demonstrated the presence of 43 aneurysms in 37 patients (6 patients presented with two aneurysms) while in 3 patients no aneurysm was found. Angio-CT post processing using MIP showed the presence of 40 aneurysms in 36 patients. Of 2 patients with 2 aneurysms, Spiral-CT demonstrated no aneurysm in one patient, while only 1 in the other one. The three aneurysms demonstrated only by angiography were 2 mm in diameter. Conclusion: Angio-CT showed itself to be a valid method in the detection of cerebral aneurysms in patients who presented ESA even if we can't assert that this is the resolutive method.

Multislice CT-angiography (MSCTA) of the hand M. Rieger, A.R. Rudisch, B.V. Czermak, R.J. Bale, M. Gabl, A. Schwabegger, W.R. Jaschke; Innsbruck/AT Purpose: To demonstrate the feasibility of MSCTA using high resolution reconstruction to depict the arteries of the hand in traumatized patients with suspected arterial injury as well as in patients with congenital malformations using volume rendering-(VR) and multiplane-volume-maximum-intensity-projection (MPVR-MIP) reconstructions. Materials and methods: MSCTA (LightSpeed QX/i, GE) was performed in 40 patients. 23 patients suffered from dislocated fractures of the wrist or the hand. Indication for CTA was a suspected arterial injury. 17 patients suffered from a congenital skeletal malformation of the hand. Indication for CTA was to demonstrate the vascular anatomy preoperatively. 1 patient with a recurrent hemangioma was evaluated after endovascular occlusion of the feeding artery. In all patients MSCTA was performed (slice-thickness 1.25 mm; HS) following intravenous contrast injection (100 -130 ml; 4 ml/s). Source images were transferred to the Advantage-Windows workstation (4.0; GE) for post-processing. Results: 11 patients presented with posttraumatic arterial occlusion caused by dislocated fragments or crush trauma. 12 patients showed displacement of the patent arteries. VR-reconstruction proved especially useful in giving detailed anatomical information. For confirmation of vascular lacerations, additional MIP-reconstructions were performed. In case of fractures with dislocated fragments the relationship of bone fragments and arteries was clearly depicted. In all patients with congenital malformations the osseous and arterial structures could be clearly visualized. The sensitivity of CTA findings was 100 % compared with intraoperative findings. Conclusion: MSCT allows rapid, non-invasive visualization of the detailed anatomy of the hand. Due to the high resolution of 2D-and 3D-reconstructions, even arteries which are less than 1 mm in diameter can be evaluated.

Normal diameter of the thoracic aorta in adults: A magnetic resonance imaging study J.-M. Garcier, R. Mofid, M. Filaire, K. Azarnouch, A. Ravel, G. Vanneuville, L. Boyer; Clermont-Ferrand/FR Objective: To determine the evolution of the diameter of the thoracic aorta with age in order to detect dilatation more reliably by imaging techniques. Materials and methods: Retrospective analysis of normal thoracic aorta MRI files of 66 subjects aged 44.1 ± 19.1 years (19.1 to 82.4 years) obtained between 1991 and 2000 on a Magnetom SP 42 1 T system (Siemens) in EKG gated T1 weighted spin echo sequences. 16 measurements were performed in the axial plane, oblique sagittal in the axis of the aortic arch plane, and oblique frontal perpendicular to the latter plane at the level of the ascending aorta, the arch and the descending thoracic aorta. Results: We found a significant difference of the aortic diameter between groups younger and older than 40 years. There was no significant difference in diameter among subjects younger than 40 years, and this group differed significantly from groups 40 to 60 years and over 60 years. However, there was no systematic correlation between aortic diameter and age. Discussion and conclusion: The aortic diameter evolves with age and there is a significant difference between subjects aged under and over 40 years. These results could contribute to define a normal aortic diameter, thereby making the diagnosis of pathological dilatation of the aorta more reliable.

The role of multislice CT-angiography (MSCTA) in polytraumatized patients with suspected arterial injuries M. Rieger, B.V. Czermak, R.J. Bale, H. Sparr, A. Mallouhi, W.R. Jaschke; Innsbruck/AT Purpose: To evaluate the efficacy of Multislice-CT in polytraumatised patients with arterial injuries and to demonstrate the role of CT-angiography as an integral part of whole-body CT-examination. Method/materials: Since installation of a MSCT in our emergency unit, MSCTA was performed in 56 polytraumatised patients with suspected arterial injuries. MSCTA and whole-body CT were performed simultaneously following an intravenous contrast bolus. Slice-thickness was set at 1.25 mm, in large scan volumes eg. the entire aorta, it was set at 2.5 mm. Raw data was transferred to a workstation for generating 2D-and 3D-reconstructions. Axial CT images and reconstructions were analysed by experienced radiologists and retrospectively compared with surgical findings or catheter angiography results.

In all patients MSCT proved to be adequate for demonstration of injured arteries within a few minutes. We detected 14 aortic/visceral and 23 peripheral arterial lesions, which were confirmed by surgery or catheter angiography. Typical lesions of the aorta/visceral arteries were false aneurysms or occlusion due to dissection. The peripheral arteries were affected by dislocated bone-fragments or by crush trauma. In 19 cases a suspected vascular injury was ruled out. MSCT allowed a comprehensive diagnostic work-up of vessel injuries within a short time. Moreover injuries of the visceral organs and bone fractures were demonstrated with the same examination. Therefore immediate surgical repair was possible in life-threatening cases. Conclusions: MSCT is a reliable, fast tool for diagnosis of vascular injuries in polytrauma. 2D-and 3D-reconstructions provide adequate details regarding the type of arterial injury and the relationship of traumatised vessels to surrounding anatomical structures.

Diagnostic possibilities of contrast MR-angiography in pathology of the aortic arch branches E.K. Iakovleva, L.A. Tyuitin; St. Petersburg/RU Purpose: To study the possibilities and to determine the role of contrast MR-angiography in the diagnosis of diseases of the aortic arch branches. Materials and method: 68 patients were examined with a suspected pathology of the aortic arch branches. Results of MRA were compared with the data of Doppler's examinations and conventional angiography. The studies were performed with MRtomograph Magnetom Vision (Siemens) 1.5 T using a body coil. Turbo MRA flash 3D was performed in a coronal projection (TR/TE 4.6/1.8 ms, FA 30, matrix 200 × 512). Magnevist was manually injected at the dose of 0.2 ml/kg with an injection rate of 2 ml/s. Start time was individually calculated. Results: Pathologic changes of the aortic arch branches were revealed in 51 cases including 28 findings of stenotic alterations of the aortic arch branches, 7 cases with occlusions, 4 with saccular aneurysm of the subclavian arteries, 3 with dissection of the brachiocephalic trunk and subclavian arteries, 1 with a double arch of the aorta, 8 with a pathologic kinking of the aortic arch branches. The revealed changes were confirmed by the data from conventional angiography in 25 patients and by Doppler examination data in 39 patients. Conclusion: Contrast MRA is of a highly informative nature. This method is fast and minimally invasive in revealing pathology of the aortic arch branches.

Magnetic resonance of thoracic aortic diseases. A pictorial essay R. Soler, E. Rodríguez, M. Bello, A. Díaz, C. Remuiñán; La Coruña/ES Purpose: To present the application of black blood, white blood and contrast enhanced 3D MR angiography in the evaluation of thoracic aortic pathology and to illustrate the importance of various processing techniques. Materials and methods: We retrospectively reviewed 359 thoracic aortic MR studies performed in our hospital in the last 5 years. Axial, coronal and oblique-sagittal cardiac-gated SE or SE-EPI T1-w and white-blood cine-MR were performed in all cases. Breath hold contrast enhanced 3D MR angiography and useful strategies for displaying 3D image data for surgical planning were obtained in 152 cases. Results: The final diagnosis of reviewed thoracic aortic pathology include: developmental abnormalities and anatomic variants (n = 77) (arch anomalies, aortic diverticulum, aortic coarctation, pseudocoarctation, Valsalva sinus aneurysm and patent ductus arteriosus), acquired aortic diseases (n = 143) (aneurysm, dissection, penetrating ulcer, intramural hematoma, aortic infections and aortitis), normal postoperative aorta (n = 107) (aortic and valvular prosthetic grafts, repaired coarctation) and surgical complications (n = 32) (pseudoaneurysm, enlarging aneurysm in Marfan's disease after repaired dissection, recurrent coarctation, persistent intimal flap distal to endovascular stents and aortic prosthetic graft infection). We will present the most useful techniques and post-processing strategies in the assessment of these pathologies. We will also highlight diagnostic pitfalls. Conclusion: 3D contrast enhanced MR angiography is a rapid and accurate modality in the diagnosis of thoracic aortic disease but is limited to assessing the aortic lumen. Black blood and white blood MR sequences are necessary to study the aortic wall, aortic valve and periaortic tissue. Conclusion: Colour artefacts can lead to signal display where flow is absent or to lack of signal where flow is present. Knowledge of these images is necessary to avoid diagnostic pitfalls and to use them to better understand the anatomic and hemodynamic changes in the vessel explored. Learning objectives: The beginner will be able to recognize, understand, and avoid the artefacts related to colour imaging. The expert will refresh his notions.

Dependent pooling: A contrast-enhanced sign of cardiac arrest during CT P.-P. Tsai, J.-H. Chen, W.-C. Shen; Taichung/TW Purpose: In this article we describe the CT features of cardiac arrest. Materials and methods: During an 18-month period, five patients were found to have cardiac arrest during CT. Abdominal CT examinations were performed for a suspicion of intra-abdominal abscess (n = 2), intra-abdominal bleeding (n = 1) or dissecting aortic aneurysm (n = 2). All patients were found to have suffered cardiac arrest immediately or minutes after the CT scanning. The positive CT features were analyzed by experienced radiologists.Results: CT images of these five cases were quite bizarre. The injected contrast agent distributed mainly in venous system. Stasis of contrast agent was found in right brachiocephalic vein, right subclavian vein, right axillary vein, and right scapular vein. Retrograde flow of contrast agent into the left brachiocephalic vein, left subclavian vein, accesory azygous vein, both jugular veins, right portal vein, left portal vein, main portal vein, and even the hepatic artery were also noted. Azygous vein, hemiazygous vein, right renal vein, right renal parenchyma, right ovarian vein, ascending lumbar veins, posterior vertebral venous plexus, posterior intercostal veins, and dorsal veins in the back were also discovered to have contrast agent pooling from the vena cava. The heart and aorta were poorly opacified. Discussion: CT image features of cardiac arrest are characteristic. Contrast agent sinks to the dependent portions of the right side of the body, mainly in the venous system and the right lobe of the liver. The hemodynamics of the distribution of the contrast material could account for the bizarre image findings.

The Results: According to D-US, blood flow velocity was much lower in the AS artery (0.14 -0.18 m/s) than in the splenic artery (SA) (0.22/0.33 m/s) of the same person, while in the AS vein velocity was slightly lower than in the "main" splenic vein (SV). SV blood flow velocities were in the normal range of values (0.12 -0.18 m/s), not significantly increased in the patients with AS. Portal vein blood flow velocities also were normal (0.11 -0.14 m/s). Hepatic RA in patients with AS determined that portal inflow into total liver blood flow was slightly, but not significantly (p > 0.05), increased (X = 67.61 % ± 5.78) in comparison to values in 10 controls (X = 70.85 % ± 5.98). Conclusion: Neither D-US nor HRA showed significant splenic and portal vein blood flow velocity increases that might be caused by the additional blood inflow from the AS. Splenic vein and splenic artery blood flow velocities were within normal range in people with AS, while they were decreased through ASV and ASA, probably depending on the size of the AS and its vessels. This study is of interest with respect to further investigations of vacularisation in hypersplenism associated with AS.

Vascular imaging in liver cirrhosis E. Lonjedo, A. Ruiz, M.D. Serrano, T. Ripollés, J.J. Martínez-Rodrigo; Valencia/ES Purpose: To assess bolus geometry for optimal bolus timing in abdominal CTA with multidetector CT scanners. Methods and material: Studies on bolus geometry and bolus timing in abdominal CTA, including experimental and human studies, were reviewed. All data were evaluated with particular attention to the design of the studies, inclusion criteria of the patients, techniques to calculate the delay, to inject the contrast media (volume, rate, site) and to evaluate the results. Results: Important descriptors of bolus geometry were peak of maximum enhancement (PME) and the time to reach PME (tPME). The rate and volume of contrast injection were parameters which affect bolus geometry mainly. Body weight appeared to be less important, although several authors found an inverse correlation between body weight and PME. Test bolus technique was not a reliable tool to calculate the PME but it appeared to be related to the time to reach 50 HU, 100 HU and 150 HU during the injection of the main bolus. Bolus tracking techniques appear to be reliable for abdominal CTA but with several technical problems related to failure to reach the selected threshold, to interscan delay and to transition delay. Based on the results a recommendation for an appropriate multidetector CTA protocol is given. Conclusion: Bolus timing should be based on accurate knowledge of bolus geometry. Both test bolus and bolus tracking techniques have several limitations.

Volume-rendered intracranial magnetic resonance angiography -initial clinical experience A. Mallouhi, S. Felber, P. Waldenberger, A. Auer, W. Judmaier, W.R. Jaschke; Innsbruck/AT Purpose: To compare volume rendering (VR) and maximum intensity projection (MIP) as post processing techniques of MR angiography in the evaluation of intracranial vascular abnormalities. Materials and methods: 62 patients underwent intracranial 3D time-of-flight (TOF) and gadolinium-enhanced (CE) MR angiography. MIP and VR images were reconstructed for TOF-and CE-MRA data sets to investigate the presence of underlying vascular abnormalities. For each detected lesion targeted MIP and VR images were performed to evaluate its morphologic features. Image quality and vascular delineation were also compared between MIP and VR images. Results: ROC analysis revealed a better detectability of intracranial vascular abnormalities with volume-rendered MR angiography. Lesion characterization was superior with VR than with MIP; lobulated aneurysms were better detected, stenotic lesions were more correctly quantified, and the feeding arteries and draining veins of arteriovenous malformations were better demarcated and their relationship to the involved vessels was more easily determined. The image quality obtained by VR was not rated significantly better than that obtained by MIP. However, the vascular delineation on VR images was found to be significantly better.

The volume rendering algorithm facilitates the interpretation and augments the diagnostic confidence of cerebral MR angiography in the detection and characterization of intracranial vascular pathologies.

Pictorial review: Expanding applications of contrast enhanced MR angiography M.A. Al-Attar 1 , D. Kathuria 1 , P.N. Malcolm 2 ; 1 Leicester/GB, 2 Boston/GB Purpose: Body MR Angiography has been revolutionized by the use of contrast enhanced techniques (CE-MRA) enabling first pass arteriography, often within a breath hold. Applications in the aorta and renal arteries are well established. This review demonstrates more recent applications performed with floating table and bolus tracking facility. Materials and methods: Studies were performed on a 1 T Philips Gyroscan NT short bore unit with 23 mT peak amplitude and 17 mT/m/s slew rate with 3D gradient echo angiographic sequences. Bolus-tracking software was used for all studies and floating table technique with bolus chase and subtraction for peripheral angiography. All patients were clinical cases, studied with the purpose of diagnosis, treatment planning or because of difficult arterial access. Results: We present case histories illustrating confirmation of a pulmonary AVM as the cause of a chest opacity in a patient with Osler-Weber-Rendu disease. Aorta to calf CE-MRA illustrates complex anatomy in a patient with difficult arterial access because of a crossover graft and anastomotic pseudo-aneurysm. Demonstrations of stenoses in subclavian and brachial arteries illustrate the use of CE MRA to plan management non-invasively. Correlation with conventional angiography is illustrated. Conclusion: Contrast enhanced MR angiography is a robust, non-invasive technique with potential for imaging a wide range of vascular systems. Improving field and gradient strengths, sequence design and bolus timing techniques will mean that CE-MRA will continue to displace conventional arteriography for diagnostic purposes.

Antihypertensive drugs influence on intrarenal vascular resistance in chronic renal failure patients P. Alivanis, A. Kotis, M. Volanaki, A. Arvanitis, G. Mitsu, L. Guindaglia; Rhodes/GR Purpose: Since antihypertensive drugs seem to influence the intrarenal blood flow we decided to investigate their effect on renal vascular resistance. Methods and materials: 80 chronic renal failure patients with hypertension were randomly divided into four groups of 20 individuals each. Each group received a different antihypertensive drug angiotensin II antagonist (AII), b-blocker (BB), angiotensin converting enzyme antagonist (ACE), or calcium channel blocker (CCB) for a period of two months. Before and after the observation period all patients underwent phasic renal arterial blood flow velocity measurement using a color Doppler-based Toshiba SSH-140A scanner with 3.5 MHz transducer. The velocity waveform of doppler signal was analyzed to give the: pulsatility index (PI = (systolic − diastolic flow velocity)/mean velocity), and resistive index (RI = (systolic − diastolic flow velocity)/systolic flow velocity). Blood pressure, biochemical indices of renal function and the indices of renal vascular resistance were compared pre and post the two months period. Results: Statistically significant (p < 0.023 and p < 0.027 respectively) decreases in RI and PI were observed only in the CCB group of patients. In the BB group we also observed a reduction in both RI and PI but the results were not statistically significant. Contrarily in both ACE and AII groups there were non significant increases in the pulsatility index while the resistivity index was increased only in the ACE group. Conclusion: With the exception of the CCB group of drugs, which significantly reduce renal vascular resistance, the most commonly used anti-hypertensive drugs do not significantly influence the intrarenal blood flow in patients with chronic renal failure.

Care bolus MRA of the carotid arteries in comparison to selective X-ray angiography R. Wutke, F.A. Fellner, C. Fellner, R. Janka, W. Lang, W.A. Bautz; Erlangen/DE Purpose: To evaluate fluoroscopically triggered (Care Bolus) CE-MRA with an elliptical centric k-space order in comparison to 3D TOF MRA and selective X-ray angiography in patients with stenoses of the carotid arteries.

Helical-CT role in the evaluation of complications of thoracic and abdominal aortic endovascular stent grafts M. Natrella, S. Baldi, P. Oronzo, M. Alessi, M. Barini, A.R. Cotroneo; Novara/IT Purpose: The aim of our study was to evaluate patients by means of helical CT in the follow-up after treatment of thoracic and abdominal aneurysms with stent grafts. Materials and methods: In the period between August 1998 and July 2001, 27 patients (23 M and 4 F) aged between 41 and 88 years were studied at 1, 3, 6, 12, 24, and 36 months after treatment with stent grafts. 22 patients with abdominal aneurysms (6 saccular and 15 fusiform) and 5 with thoracic aneurysms (3 postraumatic). All examinations were performed on Hi Speed CT/i GE (slice thickness 3 mm, reconstruction interval 2 mm and pitch 1.8) after intravenous injection of 170 ml of iodinated contrast agent, timing the start of acquisition with a bolus track technique. Results: 11 patients showed endoleaks: 10 of these had type II endoleaks one of which was graft related. One patient with endoleak was successfully treated with an interventional procedure as demonstrated by Helical CT. In 1/27 patients complete thrombosis of the left branch of the stent-graft was found. 1/27 patients acute thrombosis inside the thoracic stent was seen; this was resolved by positioning another stent inside the previous one. Finally 1 patient out of 27 required surgical treatment. No stent migrations were founded. Conclusion: In our opinion helical CT appears to be the best way to detect complications after stent-graft positioning.

Spectroscopic analysis using hematoporphyrin as a microenvironmental probe for early atherosclerotic change M. Machida, K. Kameyama, M. Onda, T. Kumazaki; Tokyo/JP Purpose: Hematoporphyrin (HP) accumulates selectively in atherosclerotic plaque and shows a specific change in its fluorescence spectrum with plaque development. In this study, we assessed the possible application of HP for photodynamic diagnosis and therapy for early-stage atherosclerosis.

Dulbecco's modified Eagle medium (DMEM) containing 10 % fetal bovine serum (FBS). The cultured smooth muscle cells and aorta specimens were subjected to laser irradiation, and the HP fluorescence spectrum was measured under Ar laser (488 nm) irradiation. Results: The HP fluorescence of SMC without added phosphatidyl choline is weak, but that of SMC cultured with phosphatidyl choline liposome is increased. Moreover, HP absorption spectra increase at 650 nm was observed in a protein lipid complex after 680 nm semiconductor laser irradiation. Therefore, the hypothesis is suggested that the photosignal was amplified in these tissues by the interaction between HP photoproducts and proteolipid complex for regression of atherosclerotic plaque after laser irradiation. Conclusion: SMC appear to be injured by addition of a cholesterol component, HP fluorescence and absorption spectra deviation to the red part of the spectrum differs from that in atherosclerotic tissue. However, HP accumulates selectively in the atherosclerotic plaque and in the damaged SMC. In the HP accumulated in atherosclerotic plaque, the laser irradiation produces photoproducts which form a protein-lipid complex as various photosensors. These photosensors are considered to have an influence on atherosclerotic change.

Non-invasive evaluation of aortic aneurysms with angioCT: Comparison of double-slice and single-slice CT units J. Baron 1 , Z. Zielinski 1 , K. Gruszczynska 2 , K. Czernicki 2 , I. Biowska-Kurkowska 1 , L. Kurkowski 1 ; 1 Tychy/PL, 2 Katowice/PL AngioCT, due to multiplanar imaging preserving the density scale and minimal invasiveness, became the second method after US in aortic aneurysm evaluation. Multislice CT scanners introduce further challenges into this area.Purpose: Comparison of the diagnostic possibilities of double-slice and singleslice CT units in the evaluation of aortic aneurysms. Material and method: 58 aortic angioCT examinations: 30 performed in the year 2001 with double-slice (MxTwin, Marconi) and 28 with single-slice CT unit (HeliCat, Elscint) were analysed. The image quality, examination time, and amount of CM according to examination techniques used in both CT units were compared. Results: 38 aortic aneurysms were found: 7 aneurysmal dilatation of the thoracic and 12 of the abdominal aorta. Dissection of the whole aortic length was found in 8 (21 %) patients, dissection of a single aortic part in 11 cases. With the doubleslice CT unit the entire aortic length during single inspiration was visualized and the CM volume was 30 % less. The large number of slices (up to 250) and long reconstruction times were the disadvantages. Conclusions: (1) Aortic imaging with the double-slice CT decreases the examination time and volume of required CM. (2) Double-slice examination, with increased image resolution, enables more accurate evaluation of aortic aneurysm morphology.

Hepatic vasculature in liver transplanted patients: Volume rendering of contrast-enhanced MR angiography P. Boraschi, E. Neri, R. Gigoni, M. Cossu, P. Rondine, C. Cappelli, P. Vagli, F. Falaschi, C. Bartolozzi; Pisa/IT Purpose: To report the application of volume rendering (VR) of contrast-enhanced MR angiography (CEMRA) in the evaluation of hepatic vasculature in liver transplanted patients.

The study group included 25 subjects previously submitted to orthotopic liver transplantation. The MRA examinations were performed on a 1.5 T system (Signa, GEMS) using a 3D coronal spoiled gradient-echo sequence (TR/TE 6.0 -6.9/1.2 -1.8; flip angle 40°; field of view 35 -42 cm; matrix 256 × 160; one signal acquired), which enabled acquisition of 32 partitions 2.0 -2.5 mm thick. A fixed dose of 20 ml gadobenate dimeglumine (MultiHance, Bracco, Italy) was administered at 2 ml/s. In two breath-holds, we acquired the first scan during the arterial phase of enhancement, and a second phase during the venous phase of enhancement. The data sets were volume rendered (Advantage Windows 4.0) and the resulting 3D models were displayed at different points of view. DSA was performed in patients suspected of having hepatic artery disease at CEMRA. One year imaging follow-up by color Doppler US and/or CT angiography was used as standard of reference in the remaining subjects. Results: CEMRA with VR provided anatomic details and patency of the hepatic artery, portal vein, and inferior vena cava. In four patients with hepatic artery pathology (2 with stenosis and 2 with occlusion) findings were confirmed by DSA. A false positive case of hepatic artery stenosis was diagnosed on CEMRA with VR. Conclusion: In patients with liver transplantation CEMRA with VR represents a non-invasive, highly effective technique for imaging the hepatic vasculature.

Congenital extrahepatic portosystemic shunt -a very rare anomaly S. Caffier, M.W. Laass, D. Müller, V. Hänig, G. Hahn; Dresden/DE Purpose: Congenital extrahepatic portosystemic shunt is a rare condition in which there is no portal perfusion of the liver. Ultimately encephalopathy develops. We report a case where splanchnic blood drained directly into the right atrium. Methods and material: We report on a 13-year old boy with a total extrahepatic portosystemic shunt leading to hepatic encephalopathy. Attention deficit problems and increasing difficulties in concentrating were noted since school age. He then developed an increased ammonia level in the blood. Investigations included an abdominal ultrasound examination, Doppler studies of the portal vein and echocardiography as well as abdominal magnetic resonance imaging (MRI) and MR-angiography (MRA) and angiography of the splanchnic vessels. Results: The ultrasound examination and Doppler studies showed no portal flow into the liver. MRI, MRA and angiography revealed an atypical portal circulation: the superior mesenteric vein and the splenic vein joined before emptying into the right atrium at the site where the inferior vena cava normally enters the atrium. There was an additional hepatic artery arising from the superior mesenteric artery, which supplied blood to the right hepatic lobe. Echocardiography demonstrated impaired left ventricular systolic function. Brain MRI revealed typical signs of hepatic encephalopathy. Treatment was the reduction of dietary protein intake. If this fails, liver transplantation might be the only surgical option. Conclusion: This is the second reported case where splanchnic blood drained directly into the right atrium. The accurate diagnosis of this rare anomaly was possible using MRI, MRA and angiography.

Multiphase MR angiography in patients suspected of having aortic dissection -initial experience M. Golebiowski, A. Cieszanowski, W. Okla, K. Milczarek, J. Szmidt, M. Szostek; Warsaw/PL Purpose: Assessment of multiphase magnetic resonance angiography (MRA) in evaluation of aortic dissection. Material and method: Eleven patients suspected of having aortic dissection underwent multiphase MRA after intravenous power injection of Gd-DTPA (30 ml; 3 -4 ml/s). Acquisition time for the single phase of the examination was 8 -10 s (TR = 5 ms, TE = 1.6 ms, 164 × 512 matrix, FOV = 270 -300 × 480). Immediately after MRA, an axial FSMGRE sequence of the aorta was performed. The quality of MRA images, as well as the type of dissection, its extent and blood supply were evaluated. Results: All MRA examinations were of good quality. In 9 of 11 patients the whole extent of the dissection was visualized. In 2 tall patients, with extensive dissection, the field of view was too small to show the whole range of disease. Three patients had type A and 7 had type B dissection, one patient had dissection confined to the abdominal aorta. The distal extension of dissection included descending aorta (n = 1), abdominal aorta above renal arteries (n = 3), abdominal aorta below renal arteries (n = 3) and iliac arteries (n = 4). The celiac trunk was supplied from the false channel in 2 cases, superior mesenteric artery in 3 cases and renal arteries in 4 cases. Conclusions: Our results suggest that multiphase MRA enables accurate evaluation of aortic dissection. Despite the use of a maximum field of view, visualization of the whole dissection may be difficult in tall patients with long aortas and extensive dissection.

Clinical usefulness of three-dimensional digital subtraction angiography for abdominal and peripheral aneurysms Y. Takei 1 , H. Mitsuoka 1 , N. Unno 1 , S. Fukuyama 1 , M. Shinmura 1 , M. Murata 1 , T. Nomura 2 , S. Nakamura 1 , H. Sakahara 1 ; 1 Hamamatsu/JP, 2 Kanazawa/JP Purpose: To evaluate the clinical usefulness of three-dimensional digital subtraction angiography (3D-DSA: Advantx LCN plus, GE Medical Systems) for abdominal and peripheral aneurysms. Material and method: 58 patients with abdominal and peripheral aneurysms were examined with 3D-DSA. Non-ionic contrast media (370 mg I/ml, 12 -60 ml) was injected at 2 -10 ml/s. The optimal delay time was decided by abdominal and peripheral angiography. After acquisition, the data was transferred to a workstation (Advantage Workstation 3.1, GE Medical Systems) and processed to generate three-dimensional images of the aneurysms. We measured the size and the extension of the aneurysms on the workstation and compared them with those derived from three-dimensional computed tomographic angiography (3D-CTA) with spiral CT (Hispeed SG-i, GE Medical Systems). Results: Compared with 3D-CTA, 3D-DSA gave a larger field of view and higher spatial resolution in a shorter acquisition time. For diagnostic purposes these superiorities of 3D-DSA were not indispensable, and 3D-CTA gave enough information concerning the aneurysm itself?. For endovascular intervention, 3D-DSA was better at visualizing small vessels arising close the aneurysm than 3D-CTA and it automatically gave the optimal angle of projection to work with. Conclusion: 3D-DSA is helpful in endovascular intervention for abdominal and peripheral artery aneurysms.

Evaluation of a new method for stenosis quantification from 3D-CT renal artery angiography images M. Shinya, K. Fukuda, T. Horiuchi, M. Jinzaki, S. Kuribayashi; Tokyo/JP Purpose: For renal artery stenosis, the rate of the stricture quantification becomes important in the field of interventional radiology. Now the 2D X-ray DSA method is used for evaluation, but this has an intrinsic limitation. A new method for the stenosis quantification of 3D-CT angiography images has been developed. We have been examining this method both on phantom and on clinical data.

The new 3D quantification method is commercially available as a software product called Advanced Vessel Analysis (GEMS). The quantification software algorithm identifies every point of interest automatically, and computes vessel length (mm), area (mm 2 ) and diameter (mm). The 2 evaluation phantoms are made up of 4 different diameter (2.0/3.0/5.0/7.0 mm) acrylic cylinders sealed in a water block. The phantom was imaged with MDCT capability (LightSpeed Plus, GEMS).

In the phantom study, the SD for errors has been always found to be less or equal to 0.15 mm, and the maximum measurement error less than 0.48 mm, mainly it depends on the cylinder angle and slice thickness. The results of 10 clinical cases showed there were no major differences between the 3D-CT quantification method and the 2D X-ray method. Conclusions: AVA quantification of renal artery has been evaluated both on phantom and clinical data. (1) In the phantom evaluation, the measurement value is effective for evaluation of the vessel diameter and area. (2) In the clinical cases, the new method for quantification of stenosis with 3D-CT angiography images is a potential alternative to quantification using 2D X-ray images.

Detection of in-stent renal artery stenosis: Multislice CT angiography vs duplex ultrasonography A. Mallouhi, B.V. Czermak, G. Bodner, M. Rieger, R. Seiler, S. Giacomuzzi, P. Waldenberger, W.R. Jaschke; Innsbruck/AT Introduction: To compare multislice CT angiography (MSCTA) and duplex ultrasonography (US) in the detection of in-stent renal artery stenosis. Materials and methods: 28 consecutive patients with 30 renal arterial stents, prospectively examined with MSCTA and duplex US within one month, were included in the study. On CTA, which was postprocessed into coronal and axial curved reformations and volume rendering views, a reduction of 50 % or more in stent lumen was considered as a significant restenosis. With duplex US, a peak systolic velocity of 226 cm/s or more indicated a significant restenosis. Correlative DSA was available in 14 patients (14 stents). Results: Follow-up was performed 25.9 ± 11.7 days after stent placement. DSA revealed a significant (≥ 50 %) in-stent stenosis in five patients, and a mild restenosis (< 50 %) in three patients. Restenosis was ruled out in six patients. Six significant and four mild restenoses were identified by MSCTA. Duplex US indicated 10 significant restenoses, ruled out a restenosis in 15 stents and yielded non-diagnostic results in five stents. Discrepancy between the two diagnostic methods was detected in seven stents. The available comparison with DSA in five of the seven cases confirmed one overestimation by MSCTA and four overestimations and one underestimation by duplex US.Conclusion: MSCTA appears to be advantageous over duplex US in the detection of restenosis in stented renal arteries.

CT analysis of the trajectory pattern in aortic dissection H. Minamiguchi 1 , M. Sato 1 , H. Saito 2 , M.D. Dake 3 ; 1 Wakayama/JP, 2 Sendai/JP, 3 Stanford, CA/US Purpose: To classify the patterns of aortic dissection propagation with quantitative data from CT angiography and to investigate the relationship between aortic dissection trajectory and the status of visceral branch vessel compromise. Methods and materials: CT images and patient data were obtained in 67 patients with acute and subacute aortic dissection extending from the thorax to abdomen. The patients (48 male, 19 female) ranged in age from 34 to 80. Axial CT images were traced at 8 pre-determined levels. The angle of the true lumen center (ATLC) and status of visceral branch vessel compromise were analyzed. The distance and angle difference between the SMA and bilateral renal arteries were calculated. Results: The trajectory of aortic dissection propagation could be divided into three groups: Straight dissection group (n = 41) and spiral dissection group (n = 26). Moreover the latter group into clockwise rotation group (n = 14) and counterclockwise rotation group (N = 12). The only significant factor was age (p = 0.030). The left renal artery was more involved than the right (p = 0.016). The distance from SMA to renal artery and the difference in angle between them were significant factors in the status of renal artery compromise (p = 0.001, 0.001). Conclusion: CT images identify unique trajectory patterns that characterize the propagation of aortic dissection. Left renal ischemia was well observed in aortic dissection; the distance and angle difference between SMA and renal artery were important. Correlation of these patterns with the frequency of branch vessel compromise provides new insight into the hemodynamics of aortic dissection.

The effect of trigger delay on image quality of ECG-gated reconstructed MDCT coronary angiography M. Jinzaki, K. Sato, H. Sugiura, A. Tanimoto, S. Okuda, S. Kuribayashi, K. Sasaki; Tokyo/JP Purpose: To evaluate the effective ECG-gated retrospective image reconstruction for multi-detector row computed tomographic (MDCT) coronary angiography in reducing cardiac motion artifacts. Materials and methods: Eighteen patients were studied with a multi-detector row scanner (GE LightSpeed Plus). 100 ml of contrast material was injected with the first 60 ml at 3 ml/s and the next 40 ml at 1.5 ml/s. The scanning delay was determined by injecting a 20 ml test bolus with a 3 ml/s flow rate. Raw helical CT data and ECG tracings were combined to retrospectively reconstruct the volume rendered images. 40 % and 70 % of the R-R intervals were used as the starting points of the reconstruction. The image quality of coronary artery with each trigger delay was compared. Results: In all cases, optimal image quality for the left coronary artery was obtained with a 70 % trigger delay. Optimal image quality for the right coronary artery was achieved with a 70 % trigger delay in 10 (56 %) cases, while with a 40 % trigger delay in 8 (44 %) cases. Conclusion: A 70 % trigger delay is recommended first to reconstruct the images of MDCT coronary angiography. In some cases, a 40 % trigger delay should be used further to evaluate the right coronary artery.

Time-resolved 3D-magnetic resonance angiography in the assessment of pulmonary vessel anomalies in pediatric patients C. Fink, J. Eichhorn, K. Brockmeier, H. Ulmer, S.O. Schoenberg, M. Bock, S. Delorme; Heidelberg/DE Introduction: The standard procedure for the assessment of pulmonary vessel anomalies in pediatric patients is conventional catheter angiography. Contrastenhanced 3D-MRA with scan times of usually over 20 seconds is often of limited diagnostic value due to breathing artifacts and venous overlay. The results of timeresolved 3D-magnetic resonance angiography in two pediatric patients with suspected anomalies of the pulmonary vessels are demonstrated. Method and materials: All measurements were performed on a 1.5 T whole-body scanner (Magnetom Vision, Siemens). The imaging protocol included an ultrafast 3D FLASH sequence with symmetric k-space sampling and a partially selfrefocussing radiofrequency pulse (TR/TE 2.3/0.9 ms, flip angle 40°, scan time 6.22 s, 0.2 mmol/kg body weight Gd-DTPA i.v.). In total 4 to 5 data sets were acquired in a single breathhold. Results: Time-resolved 3D-magnetic resonance angiography showed excellent image quality and was of diagnostic value in both patients. In one patient (11 years), an aberrant left pulmonary artery passing posteriorly to the trachea to the left (pulmonary sling) was diagnosed. In the second patient (12 years) a pulmonary arteriovenous malformation of the left lung and an aorto-pulmonary collateral artery to the left lower lung was demonstrated. Conclusion: Time-resolved contrast-enhanced 3D-magnetic resonance angiography is a suitable method for the diagnosis of pulmonary vascular anomalies in pediatric patients. In this limited number of patients the diagnostic value was comparable to conventional catheter angiography.

3D MR angiography and flow measurement with a 7 T MR imager for studying compensatory vascular growth in a mouse femoral artery occlusion model G.F. Bachmann, S. Wagner, A. Helisch, C. Müller, W. Schaper; Bad Nauheim/DE Purpose: To assess the practicability and accuracy of 3D time-of-flight (TOF) angiography and TOF quantitative flow measurement for demonstration of collaterals and reconstitution of perfusion after ligation of the femoral artery in mice. Methods: All measurements were performed on a 7.0 T Bruker imager using lowpass birdcage coils. First, the acquisition parameters for TOF technique were optimised on a flow phantom consisting of four tubes with inner diameters of 0.4 to 1.46 mm using 1.0 mmol/l copper sulfate as blood equivalent. Then, flow values were achieved with MRI on 10 mice 1 to 7 days after ligation of a femoral artery and compared with simultaneous doppler flow data. Third, the arterial and venous vessels of the pelvis and both hindlimbs of the same 10 mice were simultaneously visualised by TOF angiography. Results: TOF angiography permits imaging of the complete vascular tree of mice hindlimbs after surgical occlusion of the femoral artery with high resolution. The development of collaterals (< 100 mm) recruited from premature small arteries is clearly defined during the observation period of a week. Reduction and normalisation of blood flow was demonstrated in close coherence with Doppler flow measurement. Conclusion: 3D angiography and quantitative flow measurement using TOF techniques are reproducible and accurate methods for monitoring compensatory vascular growth after surgical ligation of the mouse femoral artery. Successive puncture of vessels and administration of contrast medium is not necessary. On the basis of about 5000 patients with clinically suspected DVT, investigated with CDS from 1995 to 2000, we have identified some patterns due to technical, anatomical and physiopathologic factors which may prove problematic for comprehension. The aim of our paper is to describe such patterns and suggest some ways in order to recognize and avoid them.

Subarachnoid hemorrage without detectable aneurysm. Accompanying findings resulting from CT-angiography and digital subtraction angiography M. Karamessini, G. Kagadis, D. Konstantinou, D. Karnabatidis, T. Petsas, G. Nikiforidis, D. Siablis; Patras/GR Purpose: To describe the accompanying findings from three-dimensional CT-angiography (3D-CTA) and digital subtraction angiography (DSA), in patients with subarachnoid hemorrage (SAH) of undetermined etiology. Materials and methods: 55 patients were admitted to our hospital with non-traumatic SAH. After plain CT, 3D-CTA and DSA were performed within the first 48 hours of admission. Two radiologists evaluated the CT-angiography images and another two, independently, the conventional angiography images. A consensus was reached by the aforementioned radiologists and a neurosurgeon that reviewed the imaging findings. Results: 20 patients (36 %) had no detectable aneurysm on both 3D-CTA and IA-DSA. The repeat DSA was negative in all patients. According to the plain CT, we divided the patients into Group A (those with a perimesenchephalic SAH-8 patients) and Group B (those with an aneurysmal pattern of SAH-12 patients). In seven patients from Group A (87 %) and in four patients from Group B (34 %), no findings were recorded. In one patient from Group A (33 %) and 8 patients (66 %) from Group B we observed the following vascular variations: an azygous A2 segment, 6 hypoplastic A1 segments, 4 hypoplastic P1 segments, 2 PCoA infundibulum, 5 fetal type PCoA configuration, 1 fenestration of A1 segment and 2 fused ACoA. Conclusion: It is well known that vascular variations are associated with an increased incidence of saccular aneurysms. We observed that they are frequent among patients with no detectable aneurysm (Group B). We consider that these secondary findings should not be disregarded and these patients should be under close follow-up.

Multiple thrombosis of abdominal arteries, due to heparin induced thrombocytopenia-hit type 2: A case report G. Terzis, T. Petsas, A. Chrysanthopoulou, F. Badra, D. Siablis, J.A. Dimopoulos; Patras/GR

Methods and materials: A 57-year-old male was referred to our hospital with multiple fractures of his left leg. He underwent surgical treatment of his fractures and was treated with administration of subcutaneous sodium heparin from the first postoperative day since the platelet count was normal. On the tenth postoperative day, the patient complained of intermittent, progressive abdominal pain, mainly localized in epigastrium, without other clinical symptoms. A blood count revealed thrombocytopenia (< 100000/ml) with a normal peripheral blood smear while clotting studies and biochemistry profile were normal. Results: Abdominal Spiral Computed Tomography with contrast medium administrtion revealed multiple blood clots in the abdominal aorta, celiac trunk, superior mesenteric artery, renal arteries and multiple infarcts in the liver and spleen. Digital Subtraction Angiography of the thoracic and abdominal aorta confirmed thrombosis of the aforementioned arterial branches. The patient was transferred in the Department of Intensive Care due to clinical deterioration and passed away 12 hours later. Conclusion: Heparin induced thrombocytopenia (HIT) is an under-recognized clinical condition which can become life-threatening. HIT should be suspected in patients who are under heparin treatment and develop arterial thrombotic disease.

Evaluation of gastric carcinoma with CT virtual gastroscopy and threedimensional imaging: Comparison with conventional barium study F. Chen, K. Zheng, S. Ju; Nanjing/CN Objectives: To assess the roles of CT virtual gastroscopy (CTVG) and three-dimensional (3D) CT imaging with upper gastrointestinal series (UGI) in the evaluation of gastric carcinoma. Materials and methods: Forty histologically proven gastric carcinoma patients were included in this study. The results of CTVG and 3D CT imaging were compared with those of UGI. Two observers blindly evaluated images of all four techniques (including CTVG, SSD, Raysum and UGI) in terms of image quality, diagnostic confidence with a five-point scale and image artifacts with a three-point scale. Sensitivities of lesion detection and classification based on Borrmann's classification of CTVG and 3D CT were determined by comparing them with UGI and pathological findings Results: There was no statistical difference in lesion (with diagnostic confidence of 3 or higher) detection sensitivity between CTVG and UGI (p > 0.05), but the lesion detection sensitivity of SSD and Raysum display was lower than that of UGI (p < 0.05). The sensitivity of Borrmann's classification of CTVG was statistically higher than that of UGI (p < 0.05). No statistical differences of sensitivity in classification, however, between SSD, Raysum and UGI were found (p > 0.05). Three cases of early gastric carcinoma were all detected only by CTVG. Conclusions: The performance of CTVG was equivalent to and superior to UGI in the detection of and in the classification of advanced gastric carcinoma, respectively. The value of SSD and Raysum display was limited in the evaluation of gastric carcinoma when they were used alone clinically.

Experimental evaluation of a low-dose scanning protocol for CT colonography using a multidetector spiral CT equipment: in vitro and in vivo study A. Laghi, R. Iannaccone, R. Passariello; Rome/IT Objective: To optimise new scanning protocol for multislice CT colonography having as primary objectives (1) improvement in lesion detection rate and (2) reduction of dose exposure. Materials and methods: In-vitro evaluation was performed on an home-made colonic phantom with three different scanning protocols: (1) high resolution (1 mm sl width; 1 mm recon interval); (2) intermediate protocol (3 mm sl width; 3 mm recon interval) and (3) high speed (5 mm sl width; 5 mm recon interval). Other parameters were kv, 120; mAs, 80; dose exposure, 9.12 mGy (nr 1) and 7.52 mGy (nr 2 -3). The optimized technique was used for scanning a selected group of patients. Subsequently, an ultra-low dose scanning protocol (2.5 mm coll; 3 mm sl width; 1 mm recon interval; mAs, 10; dose exposure, 1.37 mGy) was also evaluated. Results: In colonic phantom, lesion detection rate was 100 % for protocol nr 1, 96 % for protocol nr 2 and 85 % for protocol nr 3 (p < 0.05 for 1 -2 vs 3). Due to lower radiation exposure protocol nr 2 was implemented on 70 consecutive pts. Sensitivity for colorectal carcinomas was 100 % (15/15) and for polypoid lesions was 86.7 %. Ultra low-dose protocol (10 mAs) was implemented on 27 patients with a resulting sensitivity of 100 % for colonic carcinomas and 85.7 % for polypoid lesions. Conclusions: The optimal protocol for CT colonography is far to be defined. However, the present study has shown that a consistent reduction in dose exposure is feasible and compatible with good image quality and promising clinical results. T1-w 3D VIBE sequence. Results: The combination of barium tagged fecal material, water enema and residual air resulted in low signal throughout the colonic lumen. Intravenous injection of gadolinium resulted in avid enhancement of colonic wall and colorectal masses. Based on MRC 41 polyps were detected as well as 5 carcinomas. These findings were confirmed by conventional colonoscopy. One criterion for the differentiation between polyps and haustral folds in MRC was the increased contrast uptake in polyps (> 300 %) compared to that of the normal bowel wall (170 %). Conclusion: Barium tagged MRC obviates the need for bowel cleansing. Barium is inexpensive and has an excellent safety profile. Although the colonic lumen remained filled with stool, barium-tagged MRC permitted detection of all polyps exceeding 7 mm in diameter.

The clinical usefulness of functional magnetic resonance imaging (fMRI) in planning cortex saving neurosurgical interventions -preliminary rapport A.J. Majos, K.J. Tybor, B.J. Góraj; Lodz/PL The main aim of surgical treatment in patients with brain tumours is growth removal with possible full preservation at central nervous system functions. Purpose: The goal of our study was to establish the effectiveness of functional MRI technique in comparison with direct cortical stimulation in planning neurosurgical interventions in the sensorimotor area of the brain. Materials and methods: The study subjects were sixteen patients with supratentorial brain tumours in Rolandic area and 20 volunteers. All underwent conventional and functional MRI in the 1.5 T MRI scanner. The echo-planar technique was used during periods of rest and active movements and sensory stimulation. Activation maps were calculated by a Z-score method and superimposed on anatomical images. During the surgery the relevant centres of the brain were stimulated by the mono-or bipolar electrodes. Results: Rolandic cortex was activated by tactile tasks in all 16 patients and by motor tasks in 14 out of 16 patients. During the surgery a position of eloquent areas was determined in 15 patients. The localisation of motor and/or sensory cortex found on intraoperative mapping was similar with fMRI in 14 patients. Total tumour removal was accomplished in each case and no novel permanent neurological deficits occurred. In volunteer group the activation during execution of motor and sensory tasks was observed in all cases. Conclusion: Our preliminary data suggest that the effectiveness of fMRI technique in comparison with direct cortical stimulation is comparable.

Experimental MR-and CT-guided percutaneous cryo-and radiofrequency ablation of the spine J. Tacke, A.H. Mahnken, R.W. Günther; Aachen/DE Purpose: To evaluate the feasibility and to compare the results of percutaneous cryo-and radiofrequency ablation in porcine lumbar spine. Methods and materials: In 14 pigs, two lumbar vertebral bodies were punctured by an MR-compatible bone access device via a lateral approach under CT control. In each one vertebral body, radiofrequency ablation was perfomed using an internally cooled 17 G single probe with a 2 cm active tip (Radionics, Burlington, Mass.) for 20 minutes with maximum power of 30 W (70°C, measured at the probe tip). Further, a 2 mm MR-compatible cryoprobe (Galil Medical, Yokneam, Israel) was inserted and two freezing cycles with minimum temperature of −150°C (measured at the probe tip) were performed under MR control (1.5 T). MR follow-up was performed after one week in all and after 4 weeks in 7 animals. All 7 animals were sacrificed after 1 and 4 weeks. Results: CT-and MR-guided interventions were technically successful in all cases, neurological complications were not observed. In contrast to the heat, the ice extension was clearly visible with excellent contrast towards unfrozen bone marrow and spinal CSF. Thermal damage of the myelon/lumbar nerves was not observed in both groups. Mean lesion diameter within the vertebral body was 23/20 mm after cryoablation and 21/19 mm after RF-ablation 1 and 4 weeks after intervention. Conclusion: Both, cryo-and RF-ablation of the spine is percutaneously feasible and results in reproducible osteonecrosis. However, MR-guided cryoablation provides more safety as hypothermal effects are clearly imaged.

Patient specific surgical simulation system for procedures in colonoscopy using CT and MRI data S. Wildermuth; Zürich/CH Purpose: We have assembled a preliminary environment for simulating tasks that are performed in colonoscopy to provide a professional learning experience. Different commercial prototype endoscopy simulators exist and provide realistic interfaces, but none of these products are able to simulate realistic soft tissue deformations using patient specific preoperative CT or MRI colon datasets. Materials and methods: Virtual endoscopy examinations and virtual polyp extractions were performed on clinical cases, using both, MDCT as well as MRI. Colon models are represented as deformable objects within physically-based modeling simulation system. The simplified mass-spring system models an object as a collection of point masses connected by linear springs in a mesh structure. Common rendering options, such as coloring, lighting, solid/wire drawing and view control for virtual endoscopy are integrated in the system. The custom haptic interface is achieved by using an Immersion prototype device. Results: We can import patient specific high resolution meshes from MDCT or MRI abdominal examinations into a system that models objects with different physical properties for interaction with both non-force-feedback and haptic devices. The score tip of the colonoscope with instrument channel, irrigation, lens and light is modeled and the working channel allows interactions with different instruments as an endoscopic biopsy forceps and a snare (lasso tool) for polyp extraction. Conclusion: This virtual reality system for simulating virtual colonoscopy and polyp extraction can be used to simulate diverse procedures on a variety of pathologies in a novel physical environment and hopefully can shorten training periods and reduce complications.