key: cord-021206-4zyqqgs0
authors: nan
title: Scientific and Educational Exhibits
date: 2007
journal: nan
DOI: 10.1007/s10406-007-0215-8
sha: 
doc_id: 21206
cord_uid: 4zyqqgs0

nan

Learning Objectives: To describe principles of CT perfusion studies. To describe standard perfusion protocol for 64-MDCT in abdominal and pelvic neoplasia. To show theoretical deconvolution model for perfusion analysis. Background: 64-MDCT enables an adequate anatomic coverage and temporal resolution for perfusion analysis of solid tumor of abdomen and pelvis. Perfusion studies offer an in vivo evaluation of tumor neo-vascularity. Perfusional parameters evaluated by means of CT perfusion are blood volume, blood fl ow, mean transit time and permeability surface area product. Procedure Details: In our experience, we evaluated some cases of pancreatic tuomr, recatal cancer, urinary bladder and prostate cancer using a 64-MDCT scanner (VCT; GE). Using the follwing parameters: 650 mA, 120 Kv, 0.5 sec gantry rotation time, 5 mm slice thickness acquired for 50 seconds during i.v. administration of iodinated contrast medium (Xenetix 350; Guerbet). The anatomic coverage of the scan was of 4 cm. Image analysis was performed on off-line workstation (adw 4.2; GE) using a dedicated software based on deconvolution alghorithm. Software calculate a colored map pf different perfusional parameters and quantitative data of the same parameters in a region of interest. Perfusional index may correlate with cancer response to neoadjuvant treatments. Conclusion: CT perfusion studies represent a feasible and non invasive tool for in vivo evaluation of tumour neovascularity. 64-MDCT offer the adequate temporal and spatial resolution for the application of perfusion study to solid tumor of the abdomen and pelvis.

3 T MRI of the abdomen: Challenges and solutions for clinical application M. Kataoka 1 , T. Koyama 2 , H. Isoda 2 , A. Kido 2 , K. Tamai 2 , S. Umeoka 3 , Y. Nakamoto 2 , Y. Maetani 2 , N. Morisawa 2 , K. Fujimoto 2 , K. Togashi 2 ; 1 Cambridge/UK, 2 Kyoto/JP, 3 Wakayama/JP (mk435@cam.ac.uk) Learning Objectives: 1. To outline some challenges and solutions for 3 T MRI of the abdomen. 2. To illustrate some promising areas where 3 T MRI has a clinical impact, with the use of emerging techniques. Background: Theoretical doubling effect of SNR is the main reason of improving images at 3 T MRI. However, 3 T MRI of the abdomen seems challenging; susceptibility artifact is more prominent in abdomen due to abundant air-non air interface. Weak RF penetration and RF inhomogeneity at 3 T degrades image quality in body trunk. With fourfold increase of specifi c absorption rate (SAR), SAR limit and heating effect can be critical. In this exhibit, solutions to these diffi culties are proposed. Then potentially useful clinical applications of 3 T are discussed. Procedure Details: MR images of abdomen were obtained by 3 T (Trio:Siemens) unit using phased array coil. For solutions, a more homogeneous RF fi eld can be obtained by using dielectric pads. SAR reduction can be achieved by modifying parameters or using specially-designed sequence. Furthermore, the emerging technique of variable fl ip angle Turbo-Spin echo sequences can reduce the SAR and provides high-resolution 3D images in the order of millimeter. Promising techniques for 3 T include MRCP, breath-holding images. High-resolution images for the pelvis can provide better depiction for carcinomas of the uterine cervix, prostate and bladder. Experimental techniques such as DWI /DTI of abdominal organs can also take advantage of increased SNR at 3 T. Conclusion: Despite some challenges, 3 T MRI of the abdomen has a potential to improve image quality in a clinical setting.

Effect of diffusion-weighted image quality on abdominal apparent diffusion coeffi cient measurements T. Yoshikawa, Y. Ohno, H. Kawamitsu, M. Fujii, K. Sugimura; Kobe/JP Purpose: To assess the effect of diffusion-weighted image (DWI) quality on abdominal apparent diffusion coeffi cient (ADC) measurements and the usefulness of anisotropic images. Methods and Materials: Twenty-six patients (10 men and 16 women; mean, 58.1 years) who underwent DWI and were diagnosed not to have any abdominal diseases were analyzed. Single-shot spin-echo echo-planar DWI was performed and one isotropic and three orthogonal anisotropic images were created. ADCs were calculated for liver (four segments), spleen, pancreas (head, body, tail) , and renal parenchyma. Image quality for each organ part was scored visually. We estimated the correlation between ADC and image quality and evaluated the feasibility of using anisotropic images. Results: ADCs and image quality were affected by motion probing gradient directions in the liver and pancreas. A signifi cant inverse correlation was found between ADC and image quality. The r values for isotropic images were -0.46, -0.48, -0.70, and -0.28 for the liver, spleen, pancreas, and renal parenchyma, respectively. Anisotropic images had the best quality and lowest ADC in at least one organ part in 17 patients. Conclusion: DWI with the best quality among isotropic and anisotropic images should be used in the liver and pancreas.

Uncommon localisation of echinococcosis in the humans D. Passomenos, A. Athanassopoulou, M. Michalakou, K. Dalamarinis, L. Fois; Athens/ GR (dempasso@yahoo.com) Purpose: We retrospectively reviewed the fi les of patients who have been hospitalized with the diagnosis of hydatid disease (HD) for the past 6 years in order to fi nd unusual sites on the human body hosting this disease. Methods and Materials: 294 patient fi les were checked out and patients' mean age was 56.3 years. All patients had a computed tomography study while MRI study was done in 5 of them. Diagnosis was made by imaging features and laboratory studies and verifi ed by pathologic study wherever feasible. Results: Echinococcal cysts were identifi ed in the spleen (5), kidneys (7), abdominal cavity (3), heart (2), thigh musculature (1), spinal canal (3), seminal vesicles (3), testis (1) and ribs (2). Abdominal HD was manifested with symptoms of hydatidemesis in a case of a solitary left subdiaphragmatic calcifi ed cyst with gastro-cystic fi stula while abdominal obstruction was the fi rst sign of a disseminated intraperitoneal disease. Cysts were calcifi ed in 18 (65 %) while cyst diameter ranged from 2 to 13 cm. Primary disease was evident in 12 while abdominal HD was disseminated in 2. IV administered contrast media was given in 9, while typical confi guration of HD was identifi ed in 12 cases. Surgical excision was undertaken in 7 cases. Conclusion: Although liver and pulmonary HD is the most common form of the disease, uncommon locations do exist with low incidence. Imaging studies are of great value in depicting the nature, extend and possible complications of HD. MRI is valuable in musculoskeletal forms, while CT in abdominal disease.

Focal splenic lesions: Role of US, CT and MR imaging in their detection and characterisation I. Delgado, J. Puig, A. Malet, A. Darnell, D. Gil-Bello, J. Martin; Sabadell/ES (idelgado@cspt.es) Learning Objectives: To illustrate the spectrum of non-traumatic spleen abnormalities. To describe the imaging workup for the most common splenic diseases. To determine the current role of US, CT and MR imaging in the detection and characterization of focal spleen lesions. Background: Spleen abnormalities have received little attention in the scientifi c literature. However, recent US, CT and MR imaging advances open new possibilities in the study of splenic diseases. Procedure Details: For educational purposes, we can classify focal splenic lesions into vascular disorders (infarcts), infectious diseases (granulomas, abscesse, and so on), benign tumours (cysts, hemangioma, hamartom,and so on), malignant tumours (metastases, lymphoma and sarcoma), and other hematologic and metabolic disorders (haemochromatosis, Gamna-Gandy bodies, extramedullary haematopoiesis). Conclusion: Although most splenic lesions are detected as incidental fi ndings and have a non-specifi c appearance, the combined use of current imaging tools can often reach the correct diagnosis. US, CT and MR imaging all play an important role in the detection and characterization of focal splenic lesions, and with suffi cient clinical information, they enable the differential diagnosis of these lesions.

Parallel imaging techniques for accelerated volumetric interpolated breathhold examination (VIBE) magnetic resonance imaging of the upper abdomen D.Y.H. Huang, R. Fernando, D. Svasti-Salee, J. Dark, N. Jeyadevan; London/UK (dr.deanhuang@gmail.com) Learning Objectives: To illustrate the concept of parallel imaging. To describe the use and indications of parallel-imaging accelerated VIBE in upper abdominal MR study based on a series of 38 patients.

The VIBE is an established sequence which permits abdominal imaging in a single breath-hold. Parallel imaging is a novel technique whereby parallel coils permit more rapid spatial localisation of signal independent of conventional spatial acquisition. This allows shortening of image acquisition time. It has previously been used largely with sequences that had high intrinsic signal. Reports on the use of parallel imaging with sequences with low signal to noise such as the VIBE sequence in abdominal imaging are limited. Imaging Findings: Thirty-eight consective patients referred for abdominal MR imaging were included. All patients underwent abdominal MR study that included dynamic post gadolinium sequences with VIBE. In addition, patients underwent further accelerated VIBE sequences with parallel imaging optimised to minimise scanning time (13s vs. 20s). The images obtained with accelerated and conventional VIBE sequences were reviewed by two experienced radiologists. The accelerated VIBE sequence was comparable to conventional VIBE sequence in providing clinically acceptable images. In addition, less motion artifacts were observed in the accelerated images in the sub-group of patients who had diffi culty in breath-holding, resulting in improved image quality. Conclusion: We demonstrated the feasibility of parallel-imaging accelerated VIBE sequence in upper abdominal MR imaging. The application of parallel imaging minimises scanning time and may be useful in patients who have diffi culty in breath-holding.

Spectrum of imaging fi ndings of autoimmune diseases of liver, biliary system and pancreas M.C. Freund, I. Graziadei, A. Tzankov, K.M. Unsinn, W. Vogel, W. Jaschke; Innsbruck/AT Learning Objectives: To be familiar with pathogenesis, pathology, clinical features, and management of autoimmune diseases of liver, biliary system and pancreas relevant to the radiologist. To be familiar with typical fi ndings of various imaging modalities (sonography, MDCT, MRI, MRCP, ERCP) as well as complications and differential diagnosis of autoimmune diseases of liver, biliary system and pancreas. Background: Autoimmune diseases of liver, biliary system and pancreas are recognized as chronic progressive infl ammatory disorders of unknown etiology characterized by immunologic and autoimmunologic features, e.g. circulating autoantibodies and hypergammaglobulinemia. These diseases are associated with characteristic clinical and histologic fi ndings and include autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis, and autoimmune pancreatitis. Imaging Findings: This pictorial assay demonstrates relevant imaging fi ndings with emphasis on typical patterns for early recognition of autoimmune diseases of liver, biliary system and pancreas. Also imaging fi ndings of complications of these diseases are shown, e.g. various types of cirrhosis, hepatocellular carcinoma, cholangiocellular and cholangiocarcinoma, biliary strictures, cholestasis, cholangitis, cholelithiasis and differential diagnosis displayed by cross-sectional imaging modalities peculiar for mentioned autoimmune disease. Also, percutaneous imageguided procedures will be shown including biopsy, transhepatic cholangiography and drainage as well as endoscopic procedures including ERCP and drainage for diagnosis and therapy. Conclusion: Although autoimmune diseases of liver, biliary system and pancreas are rare, early diagnosis with recognition of typical patterns can help avert the consequences of progressive disease and unnecessary surgery.

Role of contrast-enhanced ultrasound in the assessment of spleen hemangiomas T.V. Bartolotta, A. Taibbi, M. Galia, G. Malizia, L. La Grutta, M. Midiri; Palermo/ IT (tv_bartolotta@yahoo.com) Learning Objectives: To illustrate the enhancement patterns of splenic hemangiomas (SHs) evaluated with contrast enhanced ultrasound (CEUS). Background: Hemangioma, although infrequent, is the most common primary benign neoplasm of the spleen, with a prevalence ranging from 0.3% to 14% at autopsy. SH is often discovered as incidental fi nding during an abdominal scan conducted for other reasons and more frequently observed in adults with age range from 30 to 50 years, with equal frequency among men and women. Some studies have demonstrated that CEUS is helpful in diagnosing liver hemangiomas. Procedure Details: Two experienced radiologists retrospectively reviewed by conensus baseline and SonoVue ® -enhanced US of 17 patients (10 men, 7 women; mean age: 59.5 years) with 17 SHs (mean size: 2.5 cm) -confi rmed by splenectomy (n=2), CT (n=16) and/or MRI (n=10) -evaluating baseline echogenicity and dynamic enhancement pattern of each lesion, in comparison with adjacent spleen parenchyma. At CEUS, 8/17 SHs showed an isoechoic appearance throughout the vascular phase, whereas 1/17 SH was isoechoic in the arterial phase but became hypoechoic in portal-venous and delayed phases. 4/17 SHs showed a rapid and complete fi ll-in in the arterial phase, but appeared isoechoic (n=2) and hypoechoic (n=2) in delayed phase respectively. 2/17 SHs showed peripheral hyperechoic nodules in the arterial phase, followed by progressive centripetal fi ll-in. 2/17 hemangiomas appeared as hypoechoic lesion in all phases. Conclusion: The majority of SHs evaluated with CEUS presented an isoechoic appearance throughout the vascular phase, showing in some cases contrast-enhancement patterns similar to that of liver.

Implementation of diffusion-weighted imaging in routine MR imaging of the abdomen T. Gerukis, R. Thomaidis, A. Fotiadou, A. Petridis, M. Pilavaki, V. Kalpakidis, P. Palladas; Thessaloniki/GR Purpose: To evaluate the use of apparent diffusion coeffi cient (ADC) measurements in the study of variable (histologically proven) abdomen lesions. Methods and Materials: Single-shot echo-planar diffusion-weighted MR imaging (DWI) was added to the routine abdomen MR examination with a 1.5 T MR unit in 41 patients. Images were obtained in 3 b-values (0, 500, 1000 s/mm 2 ) with generation of ADC maps. Quantitative analysis of ADC was made by region-ofinterest measurements in normal and pathologic tissue of different abdominal organs (liver 22, pancreas 2, kidney 3, adrenal 4, bowel 4, ovaries 2, bladder 1, peritoneum 3 patients).

The mean ADC value of two patients with GIST was 1.51 (x10 -3 mm 2 sec -1 ); in 4 patients with tumor recurrences (2 colon and 2 ovary cancers) it was 1.56; in 1 pancreatic cancer patient it was 1.45; in 1 adrenal metastasis from renal cancer it was 1.32; in 1 patient with desmoid tumor it was 2.04; in 4 hepatocellular carcinomas it was1.47. The mean ADC of malignant lesions was in all occasions lower than that of the benign lesions. Conclusion: Evaluation of ADC can give further information and may be used as a tool (in adjunction to the other available sequences and techniques) in successful characterization of malignant lesions in different abdominal organs, and we believe that it must take its place in everyday clinical practice. Further accumulative experience is needed to defi ne the ranges of pathologic in each occasion.

Can we refi ne our use of MRI in the management of breast cancer patients undergoing neoadjuvant chemotherapy? B.J.G. Dall, S. Kumar, K. Franks; Leeds/UK (j.mclenachan@btinternet.com) Purpose: To review and refi ne the use of MRI in breast cancer patients undergoing neoadjuvant chemotherapy.

We performed a retrospective audit of 78 patients. Everyone had a pre-treatment MRI scan, a second scan following 2 or 3 cycles of chemotherapy and a third scan at the end of treatment. The volume, extent and activity of the disease was assessed and the response to chemotherapy scored (-1=Progressed; 0=No Response; 1=Minimal Response; 2=Partial; 3=Almost Complete; 4= Complete). The third MRI scan was compared to the histology at surgery. Results: Extent of disease (fi rst MRI): MRI matched mammography and ultrasound in 62 patients (79%) and identifi ed additional disease in 17 patients (21%). Sixteen of these patients had multifocal disease. Response to chemotherapy (second MRI): 10 patients who had a complete pathological response scored 2 or 3 on the second scan. Extent of residual disease (third MRI): size at MRI equalled size at histology in 46 patients (61%), MRI<histology 19 patients (25%), MRI>histology 11 patients (14%). Conclusion: It is now the policy of our Multidisciplinary Team to use MRI after 2 cycles to change chemotherapy regimes, to plan surgery and to prompt u/s guided marker clip placement if wide local excision (WLE) is likely to be a future option and MRI shows a good response. The third MRI does not always accurately refl ect residual disease, particularly if it is multifocal but it may not be necessary if a mastectomy is planned. It does provide important information in conjunction with mammography and ultrasound if WLE is planned.

Role of diffusion-weighted MR imaging for characterization and differentiation of breast lesions F. Pediconi, E. Moriconi, F. Altomari, A. Roselli, S. Padula, V. Dominelli, C. Catalano, R. Passariello; Rome/ IT (federica.pediconi@uniroma1.it) Purpose: To evaluate the role of diffusion-weighted MR imaging for the characterization and differentiation of breast lesions. Methods and Materials: Thirty consecutive women (age range: 35-70 years) with 43 histologically confi rmed benign and malignant breast lesions were prospectively evaluated. All patients were examined at 1.5 T using a dedicated bilateral breast coil. The MR imaging protocol included axial FSE T2-weighted sequences with fat-suppression, axial EPI sequences sensitised to diffusion along 3 orthogonal directions, and pre-and post-contrast axial 3D GRE T1-weighted sequences (gadobenate dimeglumine, Gd-BOPTA; 0.1 mmol/kg). The average apparent diffusion coeffi cient (ADC) value along the 3 orthogonal directions was calculated for all lesions. Differences in main diffusivity (MD) among the lesions were evaluated by means of a non-parametric two-tailed Mann-Whitney test. Results: The 43 lesions evaluated comprised 6 fi broadenomas, 4 cysts, 13 invasive ductal carcinomas (IDC), 12 invasive lobular carcinomas (ILC), 6 ductal carcinomas in situ (DCIS) and 2 papilloma. The MD was signifi cantly higher for cysts than for benign fi broadenomas (p < 0.0002) or malignant lesions (p < 0.0002). Furthermore, the MD was signifi cantly lower in malignant respect to benign lesions (p < 0.0004). Conclusion: Diffusion-weighted MR imaging is an inexpensive quantitative procedure that can potentially serve as a corollary to established MR techniques for characterization of breast lesions. Based on diffusion properties, MD maps provide valuable information for the characterization and differentiation of breast lesions.

The effect of magnetic resonance mammography (MRM) on the clinical management of 512 women with suspected lesions during X-ray mammography or ultrasound F. Pediconi, S. Padula, F. Altomari, A. Roselli, V. Dominelli, E. Moriconi, C. Catalano, R. Passariello; Rome/ IT (federica.pediconi@uniroma1.it) Purpose: To assess the impact of bilateral breast magnetic resonance mammography (MRM) on the clinical management of patients with suspected lesions during X-ray mammography or ultrasound. Methods and Materials: 512 consecutive patients with suspected lesions during X-ray mammography or ultrasound were evaluated with contrast-enhanced bilateral MRM between October 2002 and February 2005. Indications of MRM included pre-operative staging (n=296; group 1), undetermined or suspected lesions (n=143; group 2), evaluation of mammarian prosthesis (n=52; group 3), and cancer screening in patients with familial risk (n=21; group 4). MRM, X-ray mammograms, sonograms, and histology were compared to determine the effect of MRM on clinical management in each group. Results: MRM determined changes in clinical management in 72/296 (24.3%) patients in group 1. The altered management was due to a greater lesion size in 22/72 cases, multifocality or multicentricity in 15/72 cases, multifocality/multicentricity and greater lesion size in 5/72 cases, contralateral foci in 28/72 cases, and suspected pectoral muscle infi ltration in 2/72 cases. In group 2, MRM confi rmed possible benign lesion in 71/143 patients,suspected malignant lesion in 38/143 patients, and no lesion in 34/143 patients. In group 3, MRM confi rmed a suspected broken prosthesis in 40/52 patients and confi rmed an intact prosthesis in 12/52 patients. In group 4, breast MRM identifi ed an occult tumor in 8/21 women. Conclusion: MRM demonstrates high sensitivity for the detection and characterization of suspected lesions. MRM can determine important changes in clinical management and can provide accurate guidance for per-surgical treatment.

Learning Objectives: To describe and illustrate the sonographic appearances of various benign and malignant lesions encountered in the male breast, correlate them with the pathologic fi ndings, and determine recommendations for management. Background: A majority of male breast lesions are benign, with gynecomastia being the predominant pathology. Male breast cancer represents less than 1% of all male breast disease. The most common indication for breast imaging in a male patient is a palpable mass. Sonography, in addition to mammography, is often performed for the evaluation of these lesions. Imaging Findings: The sonographic appearance of the normal male breast is reviewed. Sonographic features of various male breast lesions are illustrated and the specifi c disease entities are reviewed. Benign entities include gynecomastia, infection (abscess formation), and benign masses (lipoma, fi broadenoma, papilloma, sebaceous cyst). Malignant entities include primary breast carcinoma (invasive ductal cancer, papillary carcinoma) and lymphoma. The sonographic and mammographic imaging features are reviewed and correlated with the pathologic fi ndings. The various disease entities are discussed along with their management. Conclusion: Sonography has been shown to aid in distinguishing benign from malignant male breast lesions. Familiarity with the sonographic appearance of various breast lesions is essential in the prompt diagnosis and management of diseases of the male breast.

The signifi cance of ultrasound detected masses within the pectoralis muscle M. Diaz, A. Alonso-Burgos, M. Pons, M. Herraiz, L. Pina, G. Zornoza, B. Zudaire;

Purpose: To assess the signifi cance of masses within the pectoralis muscle detected on routine breast ultrasound studies and the diagnostic management with percutaneous procedures. Methods and Materials: From May 2000 to September 2005, 10,389 routine breast ultrasound scans were performed at our institution. These cases were retrospectively reviewed searching for ultrasound detected masses within the pectoralis muscle that were diagnosed with percutaneous procedures (14G needle core biopsy and fi ne needle aspiration). Clinical (age, palpation, previous surgery…), mammographic, ultrasonographic and pathologic fi ndings were studied. Results: Eight patients (0.07 %) had eight intramuscular masses (mean age 60.3 yrs; range 32-78). All patients had a previous malignant diagnosis (seven breast infi ltrating ductal carcinomas and one Hodgkin´s lymphoma). Two cases were palpable. Mammograms were normal in all cases. Ultrasound depicted fi ve irregular ill-circumscribed masses, two well-circumscribed masses and one seroma. Seven 14G needle core biopsies and one fi ne needle aspiration (seroma) were performed, with good tolerance and no complications. Pathology results were consistent with fi ve metastatic infi ltrating ductal carcinomas (including the intrapectoral seroma), one lymphoma, one fat necrosis and one schwannoma. Conclusion: Masses within the pectoralis muscle are extremely rare. A biopsy should be performed in these cases because of the high rate of malignancy, especially if the patient has a previous history of a malignant tumor.

Multiple logistic regression analysis of tumour descriptors for breast nodules diagnosed on ultrasonography J.T.S. Ho, S.-W. Hee, N. Gupta; Singapore/SG (ddihts@nccs.com.sg)

Purpose: Breast ultrasonography (US) is a useful adjunct to mammography in characterising solid breast masses. We set out to develop and validate a simplifi ed diagnostic score from multiple logistic regression of US features to determine the likelihood of malignancy of a solid mass. Methods and Materials: 110 patients with 128 biopsies performed in the Department of Oncologic Imaging, National Cancer Centre, Singapore, from October 2003 to June 2004 were included in the study as a training set. Images were reviewed in consensus by two radiologists blinded to the results of the biopsy. Another group of 26 lesions that were biopsied from April to July 2003 in the same centre was used as a validation set. The categories of the tumour descriptors were: shape, margin, echo texture, echogenicity, sound transmission, calcifi cations, surrounding tissue and ductal extension. Results: The training set comprised 98 (77%) benign and 30 (23%) malignant nodules. The simplifi ed diagnostic score with the form DS = 5 + 18C + 17T + 10M + 6ET + 3S + EG -5ST with a possible minimum value of 0 and a maximum value of 60 was used. Based on the ROC curve from the simplifi ed DS, a score of > 5 was considered to be malignant.Results of the validation set were comparable to the training set, confi rming the validity of the simple diagnostic model. Conclusion: A combination of US features may be used to predict malignancy, potentially allowing follow-up rather than biopsy in 27% of lesions in our validation set in this preliminary study. 

pregnancy; patients with previous breast surgery, radiotherapy or chemotherapy; tumours located less than 10 mm next to the skin or thoracic wall. Informed consent was obtained from all subjects. RFA was carried out under local anaesthesia. The electrode probe was placed in the centre of the lesion under US guidance. All patients underwent conservative surgical therapy 2-4 weeks after RFA. Complete limphadenectomy was done when axillary node metastases were demonstrated. Sentinel node biopsy was done in the remaining cases. Pathologic study included the conventional haematoxylin-eosin stein and the specifi c NADH-diaphorase study in a freezed specimen. Results: Ages: From 44 to 72 years (X:64±6.3). Tumour sizes: Between 4 and 14 mm. (X:8.5±2.8). Complete ablation with negative NADH-diaphorase test was achieved in 17 cases. One case showed a slightly positive test. In another case, the intraductal component was found out of the RFA effect ring. No signifi cant complications were observed. Conclusion: Offi ce-based RFA under local anaesthesia is a safe, feasible and comfortable procedure, accurate in 90% of the PIBC smaller than 20 mm. Wider series are necessary to evaluate the technique. Additional studies have to be directed to compare local recurrence taxes of RFA alone versus surgery.

The Background: Papillomas are generally solitary tumors of the mammary ducts epithelium and are usually located near the nipple. Patients typically report nipple discharge. Imaging features of papillary neoplasms correlate to the gross pathology. Mammograms and US are frequently normal. Occasionally, we may fi nd in mammography cluster of suspicious microcalcifi cations, gross calcifi cations, benign-appearing mass or a combination of these fi ndings. US may reveal a welldefi ned, smooth-walled, hypoechoic mass or a smooth-walled, cystic lesion with solid components. Galactography usually shows a fi lling defect. Doppler Sonography may demonstrate arterial fl ow. Imaging Findings: We have retrospectively reviewed the imaging fi ndings of intraductal papillomas from our pathology database. Out of a total of 55 patients, mammography was performed in 53, US in 51 and ductography in 28. Core-needle biopsy was performed in 20 cases with a positive result for intraductal papilloma. Intraductal papilloma was silent in mammography in 58% (31/53). A solid intraductal lesion was found in US in 36% (18/51). Ductography showed a fi lling defect in 93% (26/28). Conclusion: Intraductal papilloma has a wide spectrum of imaging manifestations depending on their hystologic subtype. We visualize them as intraductal lesions in galactography and usually in US. Ackowledgment of the typical imaging fi ndings help the Radiologist to make the correct diagnosis approach.

Mucinous carcinoma of the breast: Mammographic, ultrasonographic and MRI fi ndings with pathologic correlation E. Domínguez-Franjo, J. Oliver Goldaracena, S. Alonso Roca, M. Arguelles Pinto, E. Peña Fernandez; Madrid/ES (edfranjo@gmail.com)

Learning Objectives: 1. To evaluate the mammographic, ultrasound and MRI appearance of mucinous breast carcinoma and to correlate the imaging features with the histologic fi ndings. 2. To learn the clinical and radiological fi ndings that can forecast prognosis. Background: Mucinous carcinoma of the breast is a rare breast neoplasm that accounts for 1-7% of all breast carcinomas. They are more commonly found among elderly women. Its prevalence is strongly age related. Histologically, mucinous carcinoma can be divided into pure mucinous and mixed carcinoma depending on the volume of extracellular mucin. Pure mucinous carcinoma has better prognosis and lower incidence of metastases. Imaging Findings: The mammographic, ultrasound and MRI features are described and illustrated. The most common mammographic and ultrasonographic feature is an oval or lobular microlobulated mass with very high signal intensity on T2-weighted images, and such imaging fi ndings should suggest a diagnosis when present in an elderly patient. Conclusion: It is important for radiologists to be familiar with a variety of imaging features of mucinous carcinoma and their histologic type. This exhibit shows our experience with mucinous carcinoma focused on: 1.Clinical and imaging characteristics that should suggest diagnosis of mucinous carcinoma. 2. The mammographic, ultrasound and MRI features of mucinous carcinoma that can predict prognosis.

The multiple facets of breast fi broadenomas R. Rakheja, M. El-Khoury, K. Khetani, L. Kadoche, B. Mesurolle, M.P. Dufresne; Montreal, QC/CA (rajan.rakheja@gmail.com) Learning Objectives: To illustrate the broad range of sonographic presentations and associated uncommon pathological fi ndings of fi broadenomas. Background: Fibroadenomas are among the most common breast lesions in pre-menopausal women. Fibroadenomas typically present as palpable, oval, freely mobile, rubbery masses in young women. On ultrasound, a well-circumscribed, oval-shaped, homogenous hypoechoic mass is the most common fi nding. However, clinical presentation and sonographic appearance can be highly variable, while pathologic examination can very seldom demonstrate unusual accompanying pathological entities, such as carcinoma. Imaging Findings: Review of our database found 443 fi broadenomas that were sonographically assessed and biopsied between September 2001 and March 2006 in our institution. Fibroadenomas can be considered atypical either by their localization, occurrence in accessory breast tissue in the axilla, or by their sonographic features according to the BI-RADS classifi cation, displaying suspicious or unusual sonographic appearance. Fibroadenomas can also be associated with unusual pathologic components including extensive lobular carcinoma in situ, atypical ductal hyperplasia, ductal carcinoma in situ or even invasive ductal carcinoma. These cases will be illustrated and presented with special emphasis on their unusual features with pathological correlations. Conclusion: While most fi broadenomas are easily diagnosed by a typical clinical and sonographic presentation, the radiologist should be aware of the possibility of rare presentations, ultrasound fi ndings and even associated malignancies.

Model independent perfusion parameters of breast tumors: Potential for pathological characterization S. Makkat, V. Dewilde, M. Dujardin, T. Stadnik, S. Sourbron, R. Luypaert, J. De Mey; Brussels/BE (Smitha. Makkat@vub.ac.be) Purpose: To evaluate the usefulness of the regional perfusion parameters obtained with a model-independent analysis of second bolus T1-weighted dynamic contrast enhanced -weighted (T1-DCE) data in the differential diagnosis of breast tumors. Methods and Materials: 73 female patients (24-89 years) with histologically proven breast tumors underwent the routine MR mammography protocol which included whole breast T1-DCE and high-resolution fat suppressed sequences. A second bolus of 0.1 mmol/kg Gd-DTPA was injected and a dynamic single slice Turbofl ash acquisition (TR/TE/FA/TI 4.9/2.4/50/196, 400 images with a temporal resolution of 0.3s) was performed at the slice where the lesion enhanced maximally. The relative signal changes of the second bolus sequence were deconvolved pixelwise by a model independent method to yield the Impulse Response Function (IRF). The tumor blood fl ow (TBF) and the tumor volume of distribution (TVD) were calculated as the maximum and the time integral of the IRF respectively and the mean transit time (MTT) as the ratio TVD/TBF. Mean values of these parameters were compared between benign and malignant groups. Results: Final diagnosis included: 20 benign and 53 malignant lesions. In all the malignant lesions, the parametric maps clearly delineated tumors from the surrounding breast tissue. Mean TBF and TVD values were signifi cantly higher and mean MTT values were lower in the malignant tumors compared to the benign ones (p < 0.05).

Conclusion: A pixelwise model-independent perfusion analysis of the T1-DCE data of breast tumors provides parameters of TBF, TVD and MTT. These perfusion parameters have the potential for the differential diagnosis of breast tumors.

Sono-mammographic diagnosis of gynecomastia N.M. Abdel Razek; Cairo/EG (naglaabdelrazek@yahoo.com)

Learning Objectives: To orient radiologists to the mammographic and ultrasonographic appearance of gynaecomastia, patterns of gynaecomastia and diagnosis procedures. The relation between the different mammographic patterns to the duration and the correlation between the mammographic and the ultrasonographic appearance to the histopathological types of gynaecomastia, and fi nally when to ask for FNB in gynaecomastia. Background: Gynaecomastia is the most important disease of the male breast; it is the commonest problem affecting the male breast, accounting for about 85% of breast masses. Imaging Findings: Three mammographic appearances of gynaecomastia have been described: nodular, denderitic and diffuse patterns. Nodular gynaecomastia B D E F A G

appears as a focal retroareolar density. Denderitic gynaecomastia appears as a retroareolar density with prominent extensions that radiate into the deeper adipose tissue. Diffuse glandular gynaecomastia has a mammographic appearance similar to heterogenosly dense female breast; the glandular densities are either limited to the subareolar region or scattered throughout the whole breast. By ultrasonography, gynaecomastia has either focal hypoechic retroareolar lesion or diffuse echogenic hyper-refl ective parenchyma with or without prominent ducts, indicating development of the TLDU. It was found that the denderitic type correlates with fi brous gynaecomastia and the nodular type correlates with fl orid type. These fi ndings are directly proportionate to the duration. FNB is reserved only in suspicious cases. Conclusion: Sono-mammography has provided satisfactory results in diagnosing gynecomastia as the commonest cause of breast lump in males. Moreover, it correlates well with the radiographic fi ndings of different histological patterns.

Rare breast tumors: Imaging fi ndings and radiologic -pathologic correlation C. Martínez Lara, B. Arenas García, T. Zamora Martínez, M. Baizán García, J. Sevillano Sánchez; Zamora/ ES (cmartinezl@ono.com) Learning Objectives: To illustrate the imaging fi ndings on mammography and sonography of rare breast tumors. We add a radiologic -pathologic correlation of each entity. Background: The uncommon breast lesions cause a diagnostic dilemma and need a triple approach encompassing clinical, radiological and histological features. An exact diagnosis is crucial for the adequate management of the patient. Procedure Details: Retrospective review was performed of 626 breast lesions diagnosed in our department between January 2004 and June 2006. All patients underwent diagnostic mammography or mammography and breast sonography. The accurate diagnosis was made by core needle biopsy. We present the imaging fi ndings and radiologic -pathologic correlation of 18 selected cases of uncommon breast tumors: Six benign tumors (2 hamartoma, 1 granular cell tumor, 1 phyllodes tumor, 1 lactating adenoma and 1 intracystic papilloma) and twelve malignant tumors (4 mucinous carcinoma, 2 medullary carcinoma, 2 primary non-Hodgkin lymphoma, 1 invasive papillary carcinoma, 1 malignant phyllodes tumor, 1 carcinosarcoma and 1 metastases from carcinoid tumor).

The radiologist must know the imaging fi ndings of these unusual breast tumors and take them into account to make a correct differential diagnosis, which has a great impact on therapeutic strategies.

Diagnostic accuracy of dynamic multidetector row CT to evaluate axillary lymph node in patients with breast cancer D. Kang, J. Kim, Y. Jung; Suwon/KR Purpose: To investigate the usefulness of dynamic multidetector row CT (MDCT) in the detection of axillary lymph node (LN) metastasis using morphologic criteria and quantitative analysis. Methods and Materials: Fifty-nine patients with breast cancer underwent MDCT preoperatively. 16-slice dynamic MDCT was performed before, and 90sec and 5 min after an administration of nonionic contrast material. The morphologic features and contrast enhancement of the axillary LN were evaluated using multiplanar reformation and three-dimensional maximum-intensity projection. Short diameter of LN, S/L (short diameter/long diameter) ratio and cortical change were evaluated as morphologic features of LN. Contrast enhancement was quantitatively analyzed using a region-of-interest method to evaluate the enhancement rate and time-density pattern. Results: The hilar obliteration and eccentric cortical thickening was the most sensitive predictor for metastatic LN. The density values at each scanning time were signifi cantly different for metastatic and non-metastatic LN. The sensitivity, specifi city, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MDCT to detect metastatic LN using morphologic criteria were 81%, 82%, 83%, 79% and 81%, respectively, and the corresponding performances using quantitative analysis were 61%, 71%, 70%, 63% and 66%, respectively. In combined analysis of morphologic criteria and quantitative analysis, the overall sensitivity, specifi city, PPV, NPV, and accuracy were 65%, 93%, 91%, 70% and 78%, respectively. Conclusion: Morphologic features detected on MDCT help distinguish metastatic LN from non-metastatic, and was a more valuable diagnostic criteria than that of quantitative analysis. The quantitative analysis of axillary LN improved the overall specifi city and positive predictive value.

Quantitative refraction-based computed tomography with high resolution using synchrotron radiation E. Hashimoto 1 , A. Maksimenko 1 , S. Ichihara 2 , Y. Arai 3 , H. Sugiyama 1 , K. Hirano 1 , D. Shimao 4 , K. Hyodo 1 , T. Yuasa 5 , T. Endo 2 , M. Ando 1 ; 1 Tsukuba/JP, 2 Nagoya/JP, 3 Shiojiri/JP, 4 Inashiki/JP, 5 Yonezawa/JP (ehashi@post.kek.jp) Purpose: The ability of refraction-based contrast CT to depict breast cancer nest was tested by observing breast cancer of the human with synchrotron X-rays.

Reconstructed images of breast cancer show much detail that is noted in absorption-based CT. Methods and Materials: Recently, we have developed a new Computed Tomography algorithm for refraction contrast that uses the optics of diffraction-enhanced imaging. We applied this new method to visualize soft tissue, which is not visualized by the absorption contrast. The meaning of the contrast that appears in refractioncontrast X-ray CT images must be clarifi ed from a biologic or anatomic point of view. It has been reported that the contrast is made with the specifi c gravity map with a range of approximately 10 µarc sec. The relationship between the contrast and biologic or anatomic fi ndings has not been investigated. We compared refraction-contrast X-ray CT images with microscopic X-ray images, and we evaluated refractive indexes of pathologic lesions on phase-contrast X-ray CT images. Results: We focused our attenuation of breast cancer as samples. X-ray refraction-based Computed Tomography appeared to be the pathological ability to depict the boundary between cancer nest and normal tissue, and inner structure of the disease.

The properties of the refraction contrast provide certain advantages over other contrasts such as absorption and phase-shift. The refraction contrast can show tiny details of the inner structure, which are invisible in other types of X-ray imaging techniques. Another advantage of the contrast is the sensitivity to the low Z materials. Purpose: To analyze the clinical and imaging fi ndings of BI-RADS category 3 breast lesions by mammographic and ultrasonographic (US) assessment ultimately diagnosed as malignancy in retrospect Methods and Materials: Of 3,207 cases of US-guided core needle biopsy for 4 years, category 3 was given after biopsy, based on mammographic and sonographic evaluation, in 1,099 lesions (41.7%) that were composed of 462 palpable and 637 nonpalpable lesions. The fi nal pathology was malignancy in 18 lesions (1.6%). Each lesion was retrospectively described using BI-RADS mammographic and US lexicons, and it was assessed whether the lesions were compatible with category 3, and if not, which fi ndings suggested malignancy. Results: Of the 18 malignant lesions that were palpable in 12 (67%) and nonpalpable in 6 (33%), 9 lesions were compatible with category 3 both on mammography and on US, even in retrospect. Of 9 lesions improperly categorized as category 3, 8 (89%) were palpable. Four lesions (44.5%) were suspicious on mammography alone (calcifi cation: 2; hyperdense mass: 2), and 4 (44.5%) were suspicious on US alone (microlobulated or nonparallel mass: 2; skin retraction: 1; hypervascularity: 1) and 1 (12%) was suspicious on both examinations. Conclusion: Despite the retrospective nonblinded evaluation of mammography and US, many cases are placed in category 3. Palpable BI-RADS category 3 lesions should be more carefully assessed and should be safely managed by biopsy.

Papillary Learning Objectives: Our purpose is to make a retrospective review of the imaging findings of the papillary carcinoma of the breast, and to correlate them with the histological results. Background: Papillary carcinomas represent 1-2% of breast carcinomas. Histologically, they can be divided into in situ carcinomas, including intracystic and intraductal types, and invasive carcinomas. As a group, they are considered to have better prognosis than other breast carcinomas because of their usual slower growth. Imaging Findings: Mammography and ultrasound (including Doppler) were performed in all of the 34 patients in our series. Evaluation of lesions with both techniques allowed us to consider most of the lesions as suspicious of malignity (76.4% or 26 of 34 cases), classifying them as 4 or 5 BI-RADS categories. MRI was performed in order to reject multicentricity in 10 patients. Histologically, 38% (13 of 34) was classifi ed as invasive carcinomas. Correlation between the different histological types and the imaging fi ndings is made observing solid nodules more often associated with invasive carcinoma than cystic lesions. We also review other different aspects in our series such as age of presentation, location, size and clinical signs. Conclusion: Acknowledgement of mammography and sonography features in papillary lesions allows the radiologist to suspect carcinoma. In our experience, solid papillary carcinomas are more frequently associated with histological invasion than cystic papillary carcinomas.

Radiofrequency ablation in breast tissue: Experimental study for evaluation of heat conduction in the bovine udder B.M. Stoeckelhuber 1 , C.U. Bergmann-Koester 1 , I. Rudolf 2 , F. Noack 1 , S. Kapsimalakou 1 , A. Lubienski 1 , T.K. Helmberger 1 ; 1 Luebeck/DE, 2 Birmingham, AL/US (stoeckel@medinf.mu-luebeck.de) Purpose: To evaluate the conduction of heat in radiofrequency ablation (RFA) in the bovine udder as a model for breast tissue. Especially in superfi cial lesions near the skin surface, heat conduction and demarcation of the ablated tissue is an important issue. Methods and Materials: RFA in a lactating and a non-lactating bovine udder was performed. The needle was deployed under ultrasound guidance. The temperature was applied in 10-degree steps between 60 and 100ºC and maintained for 15 minutes at the tips of the prongs. The experiment was repeated three times for each temperature step in the lactating and non-lactating tissue. Histopathologic assessment of the resected specimens was made. The diameter of the ablation zone and demarcation of the ablated tissue margin against the surrounding tissue with respect to the temperature applied was measured. Results: In the non-lactating tissue, there is a direct correlation of the temperature and diameter of the necrosis zone. The maximum ablation diameter was 1.27 in the non-lactating tissue and 1.30 cm in the lactating tissue. There was a sharp demarcation between 0.1 and 0.2 cm in the non-lactating tissue. The transition zone in the lactating tissue was not well visualized below 80ºC, ranging between 0 and 0.2 cm. Conclusion: There is little conduction of heat in bovine breast tissue. Sharp demarcation of the ablation zone suggests accurate control of the heat, hence, ideal conditions for RFA in human breast tissue. B D E F A G

Impact of physiological bradycardia on myocardial high-energy phosphate metabolites measured by 31-P 2D CSI C. Wolf 1 , G. Klug 2 , M. Faulhaber 1 , T. Trieb 1 , M. Frick 1 , B. Metzler 1 , W. Jaschke 1 , M. Schocke 1 ; 1 Innsbruck/AT, 2 Würzburg/ DE (christian.wolf@uibk.ac.at) Purpose: 31-P-Magnetic-Resonance-Spectroscopy (31P-MRS) is a unique tool to investigate in vivo high-energy phosphates (HEP) in human heart. We intended to evaluate the impact of low-heart rates on myocardial high-energy phosphates (HEPs). Furthermore, we aimed at comparing training induced. Methods and Materials: Twenty-one male volunteers (mean age 46 ± 11 years) with a physiological heart rate (HR) below 55 bpm were compared to a group of 37 age-matched normofrequent volunteers (HR > 60 bpm). All volunteers underwent 31-Phosphorous 2-dimensional Chemical Shift Imaging (31P-2D-CSI) and cine MR images in short and long-axis acquired using breathhold ECG-triggered cine bright blood sequences to assess their myocardial HEP metabolism by determining phosphocreatinine to beta-ATP ratios (PCr/b-ATP) on the one side and heart morphology and function on the other side using a 1.5 Tesla scanner. Results: All volunteers were free of known cardiovascular disease. The detailed results of heart function (ventricular wall thickness, ventricular mass, volume of heart chambers, ejection fraction, stroke volume a.s.o). will be presented. In the spectroscopic evaluation, volunteers with a HR< 50 bpm showed signifi cantly higher PCr/b-ATP ratios than volunteers with a HR> 60 bpm (2.46±0.37 vs. 1.65±0.33, **: p < 0.0001). Conclusion: In this study, we observed a difference in myocardial HEP metabolism between volunteers with bradycardia and normofrequent volunteers. To further determine the effects of endurance training or drug-induced bradycardia on myocardial HEP metabolism, 31P-MRS might be of clinical importance since PCr/b-ATP is a prognostic marker in patients with structural heart failure.

High-resolution myocardial perfusion imaging at 3.0 T: Comparison to standard 1.5 T perfusion studies and diagnostic accuracy in patients with suspected CAD C. Meyer, K. Strach, D. Thomas, M. Hackenbroch, U. Schwenger, H. Schild, T. Sommer; Bonn/ DE (carsten.meyer@ukb.uni-bonn.de) Purpose: To evaluate high resolution myocardial rest perfusion (HRRP) in healthy volunteers at 3.0 T in comparison to 1.5 T and the technical feasibility and diagnostic accuracy of 3.0 T high resolution myocardial stress perfusion (HRSP) in patients with suspected CAD. Methods and Materials: All perfusion studies were performed using a T1-TFE-sequence. Seventeen healthy volunteers underwent a HRRP at 3.0 T (pixel size: 3.78 mm2) and 1.5 T (pixel size: 9.86 mm2). Myocardial signal intensity (SI) increase was assessed for 3.0 T and 1.5 T. Image quality was evaluated on a four-point grading scale (4: excellent, 1: non-diagnostic) with respect to homogeneity of myocardial enhancement, blurring and presence of artifacts. Nineteen patients with suspected CAD HRSP was qualitatively assessed for stress-induced hypoperfusion. Hemodynamically signifi cant CAD was defi ned as stenosis > 70% in conventional coronary angiography. Results: SI increase in HRRP at 3.0 T was not signifi cantly different from that at 1.5 T (207% ± 43 vs. 199% ± 52, p> 0.05). Image quality was signifi cantly improved at 3.0 T (3.1 ± 0.7 vs. 2.2 ± 0.4, p < 0.01). Mean score of image quality was 2.7 ± 0.7. The mean SI increase was 170% ± 30. Sensitivity and specifi city of HRSP studies at 3.0 T for the detection of signifi cant CAD was 90% and 78%, respectively. Conclusion: HRRP at 3.0 T permits signifi cantly improved spatial resolution and provides signifi cantly improved image quality in comparison to a standard approach at 1.5 T. 3.0 T HRSP is feasible in patients yielding promising results for the detection of signifi cant CAD. (1) To determine the usefulness of a new diffusion/convection (medium size) MR contrast media P846 in defi ning reperfusion after myocardial ischemia;

(2) to compare the kinetics of P846 in occlusive and reperfused ischemically injured myocardium using inversion recovery echo-planar imaging (IR-EPI), 3) to chrono-logically measure the extent of myocardial injury on P846-enhanced T1-weighted spin-echo imaging (T1-SE).

In this experimental study, rats were subjected to either of the following myocardial injuries: 30 min LAD occlusion followed by 2.5 h reperfusion (n=8) to produce non-transmural infarction, or complete LAD occlusion (n=8) to produce transmural infarction. MR imaging was performed before and after administration of 0.05 mmol/kg P846. IR-EPI and T1-SE sequences were repeatedly acquired to measure T1 and injury extent. Histopathology was performed to measure true infarcted size. Results: After administration of P846, reperfused infarct showed immediate enhancement on the T1-SE images. This fi nding was confi rmed by the sequential measurement of T1 in the infarcted and peri-infarcted zones. In contrast, occlusive infarcts appeared as hypo-enhanced core surrounded by an enhanced rim after contrast administration. The slow wash-in and wash-out of P846 from myocardium provided differentiation between occlusive and reperfused myocardial injury for 60 min. The T1 values in the occlusive infarcted gradually increased in the 50-min observation period, but it did not reach those values that were obtained in the reperfused infarct.

Conclusion: P846 provides prolonged window of discrimination between occlusive and reperfused myocardial injury. P846 provided persistent (60 min) enhancement of peri-infarcted and infarcted myocardium.

MRI of cardiac and paracardiac masses: A pictorial review G.K. Schneider, P. Fries, M. Boehm, H.-J. Schaefers, I. Kindermann; Homburg a.d. Saar/DE (ragsne@med-rz.uni-sb.de) Learning Objectives: The purpose of this exhibit is to present MRI fi ndings in both benign and malignant cardiac tumors as well as tumor-like lesions. When helpful CT imaging, catheter angiography and echocardiography as well as histologic specimens are presented, important fi ndings for diagnosis, staging and therapy planning will be highlighted. Background: Although cardiac masses are most frequently detected on echocardiography, MRI is the method of choice to accurately evaluate and further characterize cardiac tumors. Imaging Findings: An overview of imaging techniques in cardiac MRI together with proposed protocols to evaluate cardiac masses will be presented. Based on MRI fi ndings and other clinical data, algorithms that give the reader a large spectrum of information to characterize cardiac and paracardiac masses will be presented. Case studies include common and rare benign and malignant as well as tumor-like lesions, with typical and atypical manifestation, and these will be correlated with histology and surgical images. Conclusion: MRI is a valuable tool in the evaluation of cardiac and paracardiac masses. The maximum information is gained if all clinical information together with results of other imaging modalities are taken into consideration. The minimal MR protocols to characterize a lesion should be understood to add important information in the work-up of cardiac and paracardiac masses.

Safety of CMR adenosine stress perfusion imaging in patients with coronary artery disease D. Piotrowska, L. Kownacki, O. Rowinski, M. Golebiowski, G. Opolski, L. Krolicki; Warsaw/PL (dpiotrowska@plusnet.pl)

Purpose: The aim of this study was to assess safety of stress perfusion CMR imaging during adenosine infusion in high risk patients with three vessel coronary artery disease and early after acute myocardial infarction. Methods and Materials: 126 examination reports of high risk patients who underwent CMR in stress condition during adenosine infusion (140 ug/kg b.w./ min, over 4.5 min) were included in the study. 95 of studied patients had stable three vessel coronary artery disease and 31 patients were scanned within one week after acute myocardial infarction. We analyzed response pattern to adenosine infusion and frequency of adverse events. Results: Adverse events during infusion of the adenosine were observed in 56 patients (44%). The frequency of adverse events ranged from 16 % for warm feeling, 12 % for dyspnea and 8% for chest pain/discomfort to 7% for temporary atrio-ventricular block. All adverse events disappeared quickly without treatment. Signifi cant systolic blood pressure drop (more than 20 mmHg) was seen only in patients with tree vessel disease and occurred mostly in fourth minute of adenosine infusion. Only in 2 cases stress perfusion was not performed because of pressure drop. Conclusion: Stress CMR perfusion using 4.5 minutes adenosine infusion protocol is safe in patients with advanced coronary artery disease as well as early after acute myocardial infarction.

sion Scores between acute and chronic phases were also signifi cantly correlated (r=0.6, p < 0.05) and Adhesion Score in chronic phase was signifi cantly reduced compared with that in acute phase (1.3±1.0 versus 2.2±1.1, p < 0.05). In chronic phase, compared with acute phase, pericardial thickness was reduced and new lesion of pericardial adhesion was not found. Conclusion: Tagging MRI is useful for assessment of pericardial adhesion and the image obtained one month after cardiac surgery can predict pericardial adhesion in a few years.

Fast Cine sequences for evaluation of valvular heart diseases L. Natale, A. Meduri, A. Lombardo, L. Bonomo; Rome/ IT (lnatale@rm.unicatt.it) Learning Objectives: To understand relationships between fl ow disturbancies and different cine-MRI techniques. Background: Valvular diseases cause fl ow disturbances and consequent fl ow voids on GRE images depending on a variety of factors, especially echo time. Procedure Details: In 15 patients with mitral or aortic valvulopathies we compared area, length and subjective grading of turbulence jets using fast-GRE (11 and 31 kHz receiving bandwidth, prospective or retrospective gating) and SSFP cine sequences with Echocardiography as gold standard. Results: GRE cine sequences with 12-14 msec TEs display well the turbulence jets but require long scanning times and are often degraded by breathing artefacts. Fast-GRE sequences allow breath-hold acquisition but TE is forced to a minimum default value, with consequent impaired detection of fl ow voids. In fast-GRE with prospective gating, reduction of receiving bandwidth to 11-15 kHz allows 8-11 msec TEs, with more marked turbulence jets; fast-GRE with retrospective gating allows the choice of any TE coupled with a higher temporal resolution (at least 20 phases are required). In SSFP blood signal is due to T2/T1 ratio with variable turbulence jets evidence. Good correlation with echocardiography and velocity mapping data has been obtained for retrospective gated fast-GRE cine sequences. Conclusion: Turbulence jets assessment with fast sequences allows rapid semiquantitative evaluation of valvular function identifying patients needing velocity mapping measurements. Fast-GRE techniques showed different sensitivities mainly depending on echo time, but are generally suitable for fl ow assessment. SSFP techniques are not adequate for fl ow evaluation.

Left atrial remodeling after left atrial circumferential ablation for atrial fi brillation R.J. Perea, T.M. de Caralt, D. Tamborero, L. Mont, M. Sanchez, R. Salvador; Barcelona/ES (rjperea@clinic.ub.es) Purpose: The purpose of this study is to evaluate the effect of left atrial circumferential ablation (LACA) for AF treatment in left atrial (LA) volumes. Methods and Materials: Forty-one patients who underwent LACA for symptomatic drug refractory AF were included. MRI was performed only when patients were in sinus rhythm before LACA and 4-6 months after it. LA maximal volume (LAmax), LA minimal volume (LAmin) and LA ejection fraction (LA EF) were compared. Results: Pre-procedural LAmax and LAmin were smaller and LA EF was higher in the 30 patients (73%) with no arrhythmia recurrences during the follow-up. There was a signifi cant reduction of LAmax, LAmin and LA EF after LACA in the entire group. LAmax and LAmin reduction occurred in those patients with recovered sinus rhythm (97±19 to 85±19 ml and 58±18 to 52±15 ml, respectively; p < 0.05), as well as in those patients with relapsed AF (117±33 to 95±30 ml and 80±26 to 73±29 ml, respectively; p < 0.05) after ablation. No changes were appreciated in LA EF in patients with successful LACA (40±12% to 38±10%; p < 0.05), but a reduction was noted in patients with AF recurrences (33±8% to 24±10%; p < 0.05). Conclusion: LA inverse remodeling was present in all patients submitted to LACA, regardless of the clinical outcome.

Intramyocardial injection of adeno-associated viral vector encoding VEGF gene improves cardiovascular magnetic resonance measurements of perfusion and infarct resorption A. Jacquier, D. Saloner, A. Martin, L. Do, C.B. Higgins, M. Saeed; San Francisco, CA/US (alexis.jacquier@ap-hm.fr) Purpose: To determine the effects of cardiac-specifi c adeno-associated viral vector (AAV) encoding for vascular endothelial growth factor (VEGF) on regional myocardial perfusion and infarct resorption using magnetic resonance imaging (MRI). Methods and Materials: MRI was performed in swine at 3 days and 8 weeks after reperfused infarction. AAV-VEGF was injected 1h after reperfusion into the

The role of MR imaging in various cardiomyopathies E. Chun 1 , S.I. Choi 1 , W. Lee 2 , J.-H. Park 2 ; 1 Seong-Nam/KR, 2 Seoul/KR (drsic@radiol.snu.ac.kr) Learning Objectives: To learn the merit and the potential role of cardiac MRI in the evaluation of various cardiomyopathies. Background: The cardiomyopathies include a variety of diseases where the primary pathology directly involves the myocardium. Cardiac MR (CMR) is proving increasingly valuable in the identifi cation and management in these conditions. Procedure Details: We will illustrate the various MR techniques such as delayed enhancement, stress perfusion MRI, cine MRI, tagged MRI using HARP software, and VENC-MRI (for the evaluation of diastolic function) in patients with cardiomyoaphty. Also, we will present the characteristic MR fi ndings of ischemic, dilated, restrictive cardiomyopathy, arrythmogenic RV dysplasia, constrictive cardiomayoapthy, LV diverticulum, stress-induced cardiomyopahty, non-compaction, and myocarditis on the basis of our experiences. Conclusion: Familiarity with MRI techniques and features of various cardiomyopathies is considered to be helpful for the accurate diagnosis and proper management.

Evaluation of tissue iron overload in b-thalassaemia patients: A comparative study between 3.0 T and 1.5 T I. Seimenis, C. Economides, E. Eracleous, S. Kokkis, T. Posporis; Nicosia/CY (yseimen@phys.uoa.gr) Purpose: Tissue iron overload in b-thalassaemic patients is routinely assessed with MRI at 1.5 T. This work focuses on the differences and advantages of high fi eld measurements. Methods and Materials: T2 and T2* proton relaxation measurements in the heart and liver of twelve b-thalassaemic patients were obtained at 1.5 T and 3.0 T, using a respiratory-triggered multi-echo, Carr-Purcell-Meiboom-Gill spin-echo sequence (TR=2000 ms, TE 1 ,TE 2 ,…,TE 16 =6, 12,…,96 ms) and a breathold multi-echo, k-space segmented, gradient-echo sequence (TR= 22 ms, TE 1 ,TE 2 ,…,TE 8 =2.5.4.5,…,16.5 ms), respectively. Both sequences were electrocardiographically gated and prescribed along the short cardiac axis. Moreover, sequence optimization was pursued for 3.0 T measurements.

The increased SNR at 3.0 T can be used to increase in-plane spatial resolution, which is important for accurate myocardium delineation. Since the water-fat-shift is larger at 3.0 T, fat suppression is suggested for high fi eld measurements. In the patient group studied, there was no signifi cant difference between T2 values measured at 3.0 T and 1.5 T, in terms of iron overload classifi cation (low, medium or high). With regard to T2* determination, heart T2* values obtained at 3.0 T were considerably shorter than the corresponding values obtained at 1.5 T in fi ve subjects. This may be attributed to the increased susceptibility effects at 3.0 T, and may suggest a tool for assessing iron distribution in ferritin and haemosiderin deposits. Additionally, the advanced performance gradient system on the 3.0 T system allows the use of submillisecond TEs, which are necessary for T2* determination in severe myocardial iron overload. Conclusion: The use of 3.0 T seems to benefi t liver and, particularly, heart iron level determination in b-thalassaemic patients.

Assessment of pericardial adhesion after cardiac surgery by tagging magnetic resonance imaging A. Ichinose, I. Yoshioka, K. Takase, S. Takahashi; Sendai/JP (azusa@rad.med.tohoku.ac.jp) Purpose: Assessment of pericardial adhesion after cardiac surgery is very important in the conduct of repeat surgery or prediction of right-sided cardiac function.

In this study, we hypothesized that tagging magnetic resonance imaging (MRI) is useful for assessment of pericardial adhesion.

We performed tagging MRI in consecutive 33 patients who underwent cardiac surgery one month ago (acute phase) and repeated the examination in 12 of them after more than 2 years (chronic phase). Pericardial adhesion was visually scored (0=no adhesion, 1= mild adhesion, 2= severe adhesion) at two sites (post sternal bone site and right ventricular site) by one radiologist and one cardiovascular surgeon independently. The sum of scores at two sites (Adhesion Score) was obtained and compared between two readers or between acute and chronic phases.

Results: There was a signifi cant correlation between Adhesion Scores by two readers using Spearman rank order correlation coeffi cient (r=0.4 p < 0.05). Adhe-364 B D E F A G infarcted and peri-infarcted myocardium (n=6), the other 6 pigs served as control. Cine sequences (tr/te=8/5 ms, 16 phases), Gd-DOTA fi rst pass perfusion (SR-GRE: tr/te=3/1.5 ms) and delayed contrast enhancement (IR-GRE: tr/te=4.4/2.1 ms, TI=270-325 ms) were performed to measure LV function, area at risk (AAR) and infarct size. At postmortem, the hearts were stained with histochemical TTC, Masson's trichrome and isolectine B4 to characterize myocardium. Results: AAV-VEGF prevented the deterioration of LV ejection fraction in treated animals at 8 weeks. AAV-VEGF animals showed greater reduction in the AAR (39±2% at 3 days to 20±2% LV at 8 weeks) versus control animals (41±2% to 33±2%, p < 0.01). AAV-VEGF improves the reduction in extent of hyperenhanced myocardium in treated (19±2% at 3 days to 10±3% LV at 8 weeks) versus control animals (18%±2% to 15±2%LV, p < 0.01). TTC infarct size was smaller in treated (10±1% of LV) compared with control animals (14±3% of LV, p < 0.001). Histology showed increase in thin-walled arterioles (38±2/mm² in treated versus 6±2/mm² in control) and capillaries (1065±78/mm² in treated versus 576±50/mm² in control) in the injection sites. Conclusion: Intramyocardial injection of AAV-VEGF signifi cantly improved MRI measurements of myocardial function and perfusion. The therapy also increases infarct resorption by promoting angiogenesis.

Role of cardiac magnetic resonance imaging (MRI) in the follow-up assessment of tetralogy of Fallot (TOF) repair P. Serrano Gotarredona, S. Navarro Herrero, L. Aguilar Sánchez, L. Garcia Camacho, I. Gutierrez Jarrín; Sevilla/ES (mp.serrano.sspa@juntadeandalucia.es)

Purpose: To assess the value of cardiovascular MRI in the follow-up of Tetralogy of Fallot after complete reparative surgery.

We include all the patients who were survivors of TOF surgical repair and were explored by MRI in our institution during the last two years. The protocol included 3D MR angiography (MRA) to delineate pulmonary arteries anatomy; spin-echo and gradient echo sequences to delineate right ventricular outfl ow tract (RVOT); balanced steady state free precession (b-SSFP) cine-imaging to quantify ventricular function; and phase-contrast velocity mapping (VEC-MR) to quantify pulmonary regurgitation (PR). Results: We studied 16 patients aged between 4 and 34, 11 of them older than eighteen years. The estimated value of ejection fraction of the right ventricle was over 50% in eight subjects, and under 40% in fi ve. Up to thirteen had PR. VEC-MR sequences concluded regurgitation fraction equal or over 50% in three cases, between 40 and 50% in two, between 27 and 40% in other seven. The last one had a PR of 10%. 3D MRA showed pulmonary artery branches stenosis in seven cases. It was severe at the level of the anastomoses a case of prosthetic conduit placement because of RVOT re-stenosis. b-SSFP sequences showed residual ventricular septal defect in two patients. Conclusion: Cardiac MRI is a valuable method to evaluate and follow-up TOF patients who had undergone complete surgical repair. It not only provides valuable anatomic information about RVOT and pulmonary arteries, but also quantifi es ventricular function and pulmonary regurgitation.

Cardiovascular magnetic resonance in the follow-up of adults with corrected tetralogy of Fallot: A useful tool to indicate reoperation? F. Baudraxler, M. Bret-Zurita, E. Cuesta, A. Aroca, J. Oliver, A. Sánchez-Recalde;

Purpose: To demonstrate that CMR can be a useful imaging modality to indicate reliably a re-operation in patients with repaired tetralogy of Fallot (TOF). To show the indications for reoperation in our patients. Methods and Materials: Seventy-six CMR imaging studies of patients with repaired TOF performed between January 2004 and September 2006 were reviewed. A 1.5 T Signa LX 9.1 Echo-Speed GE MR system, body or cardiac array coils were used. SE T1 ECG-gated, FIESTA, PC Flow sequences and MR-Angiography 3D with MPR and VRT reconstructions were employed. Morphology and size of cardiac cavities and aneurysms of the right ventricular outfl ow tract (RVOT), right ventricular ED and ES volume, stroke volume, cardiac output, ejection fraction (EF), pulmonary blood fl ow, and morphology of the pulmonary tree were analyzed. Results: Parameters provided by CMR which indicated reoperation were the following: right ventricular ED volume> 190 ml, EF less than 30%; regurgitation fraction more than 50% and aneurysm of RVOT > 5-6 cm. Forty-six reoperations were performed in 39 patients. The most common indications referred to aortic root and valve (n=10), right ventricle to pulmonary artery (RV-PA) conduit obstruction (n= 9), and enlargement of the RVOT inserting a pulmonary valve prothesis (n=8).

Mean age at reoperation was 27 years and the average time between the corrective repair and reoperation was 19 years. Conclusion: CMR is a diagnostic imaging modality to indicate reoperation in all our patients with repaired TOF. However, we still need new techniques for a better interpretation of CMR parameters in order to determine the right moment for reoperation.

Cardiac MRI in patients with previously treated congenital heart disease: Long term follow-up results A. Sias, A. Balestrieri, C. Politi, G. Mallarini; Cagliari/ IT (alessandrosias@hotmail.com) Purpose: The purpose of this study is to display the fi ndings of cardiac MR examinations performed on a group of patients treated for congenital heart disease when infants or children, after a period of relative well being which lasted for several years. Methods and Materials: Among a Sardinian population of about 1,200 patients surgically treated for congenital heart disease on an average of 15 years before we randomly selected 120 of them and examined with standard cardiac MR to evaluate the heart morphology, and whether they had any abnormalities which could have gone undetected with other follow-up examinations to which they had been routinely subjected.

We discovered a number of pathological fi ndings which were not noted, or underevaluated with other imaging examinations and/or clinical examinations. Conclusion: Follow-up cardiac MR examinations in patients with congenital heart disease surgically treated, even after a long term interval after the intervention, can be useful in defi ning the evolution of cardiac morphology and the development of iatrogenic or surgery related abnormalities, which might go undetected by standard follow-up examinations.

Aortic coarctation: Evaluation with cardiovascular magnetic resonance angiography using time-resolved imaging of contrast kinetics ( Background: Cardiac Magnetic Resonance (CMR) in children may be limited in unravelling all details concerning the heart and great vessels. CMR is very attractive, however, for it allows an optimal anatomical and functional analysis and does not require iodine nor radiation exposure. Standard 3D Magnetic Resonance Angiography (3D-MRA) series may not reveal all anatomical abnormalities because of incorrect timing of peak enhancement. For a better display of the cardiovascular fi ndings, it would be desirable if one could reconstruct such structures at different contrast transit times. The 3D-MRA with TRICKS, available in GE MR scanners, furnishes sequential MRA Gadolinium-enhanced series and allows the selection of the best contrast-enhanced series to study a particular vessel. It would, therefore, be very useful in the evaluation of Aortic Coarctation. Imaging Findings: Patients' mean age was 1.2 years (0-12) and they were referred to either diagnose aortic disease or to post-treatment follow-up. All images underwent extensive time-resolved reconstructions at dedicated workstations and 3DVR data sets were reconstructed in order to unravel the anatomy of the aorta and its main branches. Conclusion: TRICKS is a powerful tool in the evaluation of Aortic Coarctation for it allows precise identifi cation of the aorta disease and of additional cardiovascular malformations, such as PDA. This was the fi rst MRA technique to provide 3D temporal display of the fl ow-abnormalities.

Evaluation by MRI of left ventricular remodelling and global functional recovery in patients treated with granulocyte-colony stimulating factor (G-CSF) after acute myocardial infarction (AMI) L. Natale, A. Bernardini, A. Meduri, A. Leone, F. Crea, L. Bonomo; Rome/IT (lnatale@rm.unicatt.it) Purpose: To assess by MRI the effect of i.v. administration of G-CSF on global myocardial function after AMI. Recent data suggest better outcome and functional recovery in patients with AMI treated with stem cells therapy, both with intracoronary delivery or hematopoietic precursor mobilization by G-CSF. Methods and Materials: Eight patients with anterior AMI, treated with primary PTCA (TIMI 3) and i.v. administration of G-CSF (5 µg/kg for 5 days), were studied C 365 B D E F A G by 1.5 T MRI within 7 days and after 3-5 months. Functional, perfusion (FP) and delayed enhancement (DE) studies were obtained. Values were compared with eight control patients (anterior AMI, primary PTCA). FP and DE were scored basing on number of segments involved and on transmural extension. Correlation of FP and DE with functional outcome and differences between the two groups, accounting for FP and DE extent, were assessed with Univariate (LR) and Multivariate Linear Regression (MLR) and Covariance Analysis (ANCOVA). Results: LR showed signifi cant correlation between DE-score and follow-up EDV (FU-EDV), ESV (FU-ESV), and EF (FU-EF). No signifi cant linear correlation with FP-Score was found. MLR and ANCOVA showed a positive trend in G-CSF group for all functional indexes, accounting for differences in DE (effect of G-CSF, expressed as LS-Means: FU-EDV= -22.19±41.54 ml; FU-ESV= -25.13±37.37 ml; FU-EF= +5.43%±10.07). The effect of G-CSF approached statistical signifi cance only for FU-ESV (p=0.06). Conclusion: We found a positive trend with partial statistical signifi cance regarding global functional recovery in patients treated with i.v. G-CSF after AMI. These data, however, need to be confi rmed in a larger series.

Delayed enhancement in patients with dilated cardiomyopathy is unrelated to virus persistence or the presence of infl ammation in myocardial biopsies S. Langner, J. Ruppert, K. Hegenscheidt, A. Staudt, N. Hosten; Greifswald/DE (langso@uni-greifswald.de) Purpose: Dilated cardiomyopathy (DCM) is a frequent cause of heart failure. Some patients show delayed enhancement (DE) in contrast-enhanced MRI (ceMRI). The pathologic surrogate of DE is unknown in DCM. Virus persistence and myocardial infl ammation can be shown in a considerable proportion of myocardial biopsies of patients with DCM. The study compares the histological fi ndings with the presence of DE in the ceMRI of DCM patients. Methods and Materials: Twenty-two patients with DCM underwent ceMRI after myocardial biopsy. Biopsies were taken from the right ventricular part of the interventricular septum (IVS) and analyzed for viral genomes and infl ammation. MRI was performed on a 1.5 T MRI scanner. Images for DE were acquired 20 minutes after injection of Gd-DTPA and were visually assessed for DE. This was categorized regarding the location in the myocardium and the distribution pattern.

The most abundant pattern of DE was a stripe-like lesion in the midwall portion of the IVS. There was no signifi cant correlation for DE and the cardiac parameters. Seven myocardial biopsies were positive for viral genomes (31.8%). Three of the 7 virus-positive patients (42.9%) showed DE versus 4 of the 15 virus-negative patients (26.7%), with no statistically signifi cant difference. Myocardial infl ammation was detected in 12 patients (54.5%). DE was present in 3 of these patients (25%) and in 4 of the remaining 10 patients (40%), with no signifi cant difference.

The presence of delayed enhancement does not correlate to myocardial virus persistence or to the presence of myocardial infl ammation in myocardial biopsies of patients with DCM.

Meta-analysis: Coronary calcium score as a predictor of atherosclerotic cardiovascular disease events in asymptomatic patients S.K. Ternovoy, V.E. Sinitsyn, S.P. Morozov; Moscow/ RU (spmoroz@mail.ru) Purpose: To defi ne predictive value of coronary artery calcium (CAC) scoring in identifying asymptomatic patients at higher risk of atherosclerotic cardiovascular disease (CVD) events (non-fatal myocardial infarction, coronary death, and coronary revascularization).

The data from previously published studies (indexed in PubMed Medline) were extracted for the meta-analysis. The studies should have reported CAC scores and prospective registration of CVD events in order to be included in the meta-analysis. Relative risk (adjusted for traditional risk factors) was used as a meta-meter for CVD events in 3 CAC score subgroups of patients. We tested data for publication bias, applied Q-test for heterogeneity, and analyzed individual weights of the studies. Results: Our meta-analysis included 8 studies. The studies were very heterogeneous in terms of patients' age, sex, race, and duration of follow-up. The pooled relative risk calculated on the basis of random effects model was 2.1 for CAC scores 1-100; 5.0 for CAC scores 100-400; and 9.3 for CAC scores > 400. The analysis of the infl uence of individual studies on the pooled relative risk allowed identifying the outlying studies.

The results of the meta-analysis demonstrate that relative risk of CVD events signifi cantly increased with higher CAC scores. We conclude that CAC score is the risk factor independent of CVD events, since the pooled relative risks were adjusted for traditional risk factors. The effect of outlying studies on the pooled estimates may be explained by the different representation of genders, blinded endpoint validations and registrations, and longer follow-up.

The use of a CT cardiac bowtie to improve image quality and reduce patient dosage J. Gao, X. Sun, J. Li, R. Dai, G. Wang, N. Li; Beijing/ CN (jianying.li@med.ge.com) Learning Objectives: To demonstrate the potential of using an application-specifi c bowtie to improve cardiac image quality and reduce patient dose. Background: Using application-specifi c bowties can reduce X-ray dose for CT imaging. GE VCT provides a cardiac bowtie (CB) that redistributes X-ray fl ux to concentrate on the heart. This study evaluates the dose-reduction potential of such bowtie by comparing it to the use of traditional large bowtie (LB) using patient scan data. Imaging Findings: Thirty cardiac patients in each group with similar sex, age, height, weight and heart rate distributions were scanned with LB and CB, respectively. Two experienced radiologists quantitatively evaluated the image quality blindly in terms of the number of coronary arteries identifi ed, vessel edge sharpness and contrast agent clarity in the vessel using scores of 1-4, with 4 being the highest. CTDIw values and image noises for the two sets were measured and statistically analyzed using t-test. The image quality scores for the CB and LB groups were 3.73±0.34 and 3.72±0.29, respectively, with no statistical difference (p> 0.05). However, the CTDIw values for groups CB and LB were 77.66±6.97 mGy and 83.97±7.60 mGy, respectively, with t-test of p=0.0015 indicating statistically signifi cant lower dosage with cardiac bowtie. In addition, the noise measurements for the CB group was statistically lower than those of LB (27.80±4.33 vs. 30.05±3.18 with p=0.025).

The application-specifi c cardiac bowtie on VCT reduced the overall dosage to cardiac patients and image noise without adverse impact on other clinically relevant parameters. (4) with neither NCP nor CP. Groups were compared as to age, sex, coronary risk factors (CRFs). Results: The 4 groups had 81.43,147, and 77 subjects, respectively. The incidence of hypertension and diabetes mellitus (DM) were higher in Group (1) (69% and 36%) than in (4) (34% and 12%). The incidence of CRFs, number of males, DM, hyperlipidemia (HL), and smoking were signifi cantly higher in (1) than in (2). In logistic models, HL and obesity (relative risks 2.40 and 2.52) were associated with incidence of FCP adjoining NCPs. Furthermore we divided group (2) into two groups: (2 A) with exclusive NCP without any CP or (2B) with NCP separate from CP. CRFs were 2.6 (2B) and 1.5 (2 A) and that of (2 A) was similar to (4). Conclusion: CRFs were more frequent in subjects with FCP adjoining NCP than in other groups. FCP adjoining NCP may indicate the advanced arteriosclerosis. Conversely, CRFs were less frequent in subjects with exclusive NCP than in other groups with any NCP and/or CP but similar in subjects with neither NCP nor CP and presence of exclusive NCP may indicate early staged arteriosclerosis.

Presence of focal fatty infi ltration of the right ventricular wall in asymptomatic patients undergoing screening coronary calcium scoring on EBCT J. Kirsch, E.E. Williamson, J. Glockner; Rochester, MN/US Purpose: Macroscopic focal fat deposition along the free wall of the right ventricle (RV) has been historically associated with arrhythmogenic right ventricular dysplasia. Recently, it has been shown that this fi nding can be seen in patients without ARVD. In this investigation, we assess the incidence of fatty infi ltration of the RV in a cohort of patients without clinical evidence of ARVD. Methods and Materials: 120 consecutive patients undergoing non-contrast ECGgated EBCT for coronary calcium scoring comprised the study group. Images were evaluated for the presence or absence of RV fatty infi ltration as well as additional fatty proliferation in the mediastinum, lipomatous hypertrophy of the interatrial septum, and changes of thoracic surgery. Medical records were assessed to obtain age, gender, body-mass index, and arrhythmias detected on ECGs obtained within 6 months of imaging. Patients with surgical changes were excluded to avoid falsenegatives secondary to artifact. Images were evaluated, by consensus, by 2 of 3 dedicated cardiac radiologists. Results: Of the 120 patients, 12 were excluded due to lack of required information in the medical records and/or surgical changes. 12/108 (11%) patients had fatty deposition along the RV wall. Conclusion: Focal fatty infi ltration of the RV is a fairly common fi nding in the patient population, and should not be considered as defi nitive evidence of ARVD.

Three Learning Objectives: To describe the wide spectrum of the anomalous pulmonary venous return. To understand pathophysiology and radiologic features of this entity and diverse post-operative anatomical and hemodynamic changes. To evaluate the utility of three-dimensional CT angiography in the diagnosis and management of this entity. Background: Anomalous pulmonary venous return shows diverse anatomical and hemodynamic spectrum, which range from isolated incidental fi ndings to components of more complex anomalies, most often congenital heart disease. Correct diagnosis with CT angiography affects the patient's treatment and allows avoiding unnecessary invasive studies. Procedure Details: We retrospectively reviewed CT angiography with 3D reconstruction images of 41 consecutive patients with anomalous pulmonary venous return (16 PAPVR and 25 TAPVR) from June 2002 to March 2006. Twenty-nine pre-operative CT angiography were available and 21 post-operative CT angiography were available; among them, both pre-and post-operative CT angiography were available in 9 cases. We will show the diverse spectrum of anomalous pulmonary venous return and remind the check points in imaging interpretation to provide critical information for surgical planning and post-operative evaluation. Conclusion: Three-dimensional CT angiography provides precise and excellent overview of the diverse spectrum of anomalous pulmonary venous return, noninvasively. In addition, it allows in assessing other anomalies involving the bronchial tree or visceral organs. This exhibit will help you to understand the characteristic imaging features and diverse post-operative anatomical and hemodynamic changes of this entity, and to remind the information critical for surgical planning and postoperative evaluation.

Initial experiences of 'SnapShot Cine' -low dose prospective electrocardiograph (ECG)-triggering coronary 64-slice CT angiography (CTA) M. Kiguchi 1 , J. Horiguchi 1 , K. Ito 1 , K. Marukawa 1 , C. Fujioka 1 , M. Ishifuro 1 , T. Furukawa 1 , Y. Shen 2 , F. Watanabe 2 ; 1 Hiroshima/JP, 2 Tokyo/JP (kiguchi@hiroshima-u.ac.jp) Learning Objectives: To demonstrate low radiation dose in 64-slice coronary CTA using prospective ECG-triggering. To demonstrate reduction of banding and cone beam artifacts by 3D back projection (3DBP) algorithm. Background: Diagnostic capability of 64-slice CTA for coronary artery disease has been already accepted and become a widely spread use. The major drawback of the technology is the high radiation dose caused by data acquisition with retrospective-ECG gating on which the raw data includes cardiac phases not contributing in image reconstruction. Advancement of ECG-modulated retrospective-ECG gating technique and prospective ECG-triggering scan are strongly desired to overcome this problem. Procedure Details: A 64-row x 0.625 mm-collimation confi guration (40 mm) (GE Healthcare) is used for data acquisition with prospective ECG-triggering. Three or 4 X-ray exposures per examination with 5 mm overlapping cover 11 cm or 14.5 cm in z-axis. Banding artifacts, which are caused by misregistration of data and have been observed so far on retrospective-ECG gating scan, are reduced. Conebeam artifacts seen on multi-slice CT technology are also reduced by 3DBP algorithm. We present initial experiences of this software as to dose saving and image quality. The image quality was assessed on motion artifacts and data continuity (occurrence of banding artifacts), with relation to the scanning time and heart rate. Conclusion: 'SnapShot Cine' 64-slice coronary CTA using prospective ECG-triggering, with signifi cantly reduced dose, has a potential to replace retrospective-ECG gating CTA.

Cardiac CT for the stratifi cation of cardiovascular risk in patients undergoing major non-cardiac surgery: Background, rationale and possible diagnostic algorithm L. Damiani, A.L. La Fata, E. Maffei, A.A. Palumbo, F. Notarangelo, A. Aldrovandi, F. Cademartiri; Parma/ IT (damianilaura@virgilio.it) Learning Objectives: To provide current methods and guidelines for stratifi cation of cardiovascular risk in patients undergoing major non-cardiac surgery. To understand the rationale for stratifi cation of cardiovascular regarding different implications of inducible myocardial ischemia in the surgical theatre. To provide an algorithm for stratifi cation of cardiovascular risk in patients undergoing major non-cardiac surgery that includes Cardiac-CT. Background: In daily clinical practice, patients undergoing major non-cardiac surgery need a stratifi cation of their cardiovascular risk. This is performed by means of scoring methods and diagnostic tests (i.e. ECG, stress-ECG). However, these tests are sub-optimal and because of their low sensitivity and specifi city may under/over-estimate the potential risk. Conventional coronary angiography, which is the diagnostic gold standard, cannot be performed in all patients since it is invasive and the prevalence of signifi cant disease is intermediate or low. Cardiac-CT is a non-invasive method for assessment of signifi cant coronary artery disease characterized by a high sensitivity and negative predictive value. In addition, it can provide the coronary atherosclerotic plaque burden and the type of lesions associated with an individual patient undergoing surgery. These additional informations can change surgical and anaesthesiological management. Procedure Details: 1. Description of current scoring methods and guidelines for pre-operative cardiovascular risk assessment. 2. Description of cardiac-CT features that may improve stratifi cation of cardiovascular risk. 3. Description of a diagnostic algorithm for patients undergoing major non-cardiac surgery including cardiac-CT. Conclusion: Cardiac-CT may become in the future a standard diagnostic method for the stratifi cation of cardiovascular risk in patients undergoing major non-cardiac surgery.

Thrombi in the left cardiac appendix with state-of-the-art multislice CT: A reason for discussion between radiologists and cardiologists? To provide examples of discrepancy between those techniques (Ultrasound positive and CT negative and viceversa). 3. To explain the possible reasons for this discrepancy. Background: TTE is not an optimal technique for the examination of the left appendix. TEE is the current clinical gold standard but it is invasive and operator dependent. 64-slice CT is a non invasive modality providing a non operator dependent assessment of the cardiac chambers. The current generation of Multislice CT scanners uses ECG-gating, sub-millimiter spatial resolution and good temporal resolution to provide increasingly accurate assessment of coronary artery. It also allows the detection. 

Basics of ECG for CT of the heart: What radiologists need to know A.A. Palumbo 1 , E. Maffei 1 , L. Damiani 2 , L. La Fata 2 , A. Aldrovandi 1 , F. Notarangelo 1 , F. Cademartiri 1 ; 1 Parma/IT, 2 Palermo/IT (alepalumbo@gmail.com)

Learning Objectives: 1. To provide ECG fundamentals for correct CT setting. 2.

To correlate ECG traces and CT appearance of coronary arteries. 3. To give tips and tricks for ECG post-processing editing for good image quality in patients with irregular heart rates. Background: ECG and physical examination are the primary evaluations performed to overview heart conditions. The knowledge of ECG is becoming familiar to radiologists involved in non invasive cardiac imaging. Several studies have demonstrated that the synchronization of the scan with an optimal ECG track (i.e. sinus rhythm, heart rate < 65 bpm, no premature beats) minimizes image motion artifacts and signifi cantly increases image quality. In clinical practice, patients with coronary artery disease may have irregular heart rates and software upgrades for CT-CA can help the radiologists to handle premature beats, bigeminism, irregular heart rhythms and other abnormalities. Procedure Details: Drawings for the explanation of ECG basics are presented. Several examples of heart beats abnormalities are shown and improvement of image quality is reported before and after ECG editing. A correct placement of ECG electrodes is mandatory to avoid signal artifacts: It is described how to get the best ECG signal. Conclusion: In clinical practice, patients with coronary heart disease may have irregular heart rates. In the near future, irregular heart rhythm will be not considered as an exclusion criteria for CT of the heart and ECG-editing will become routine in enhancing the image quality and allowing the inclusion of more patients for cardiac CT.

Non Background: Atrial septal defects (ASD) and patent foramen ovale (PFO) are one of the most common cardiac abnormalities. They predispone to cerebral ischemia as a result of paradoxical thromboembolism by right-to-left shunting under conditions or physiologic maneuvers that raise right atrial pressure (valsalva maneuver). Percutaneous defect closure is reliable for a decade and it needs an accurate depiction of atrial anatomy for a correct surgical planning. Since now, trans-esophagel echocardiography has provided the anatomical and functional informations. Cardiac CT, thanks to an higher spatial resolution, a non-invasivity, a better reproducibility of measurements can provide excellent images of atrial anatomy, helping to correctly choose the best occluder device. Procedure Details: 64-slice CT allows a motion-free 3D images of ASD and PFO. All dimensions of tissue surrounding the defect are measured in systole (during ventricular dyastole) and in dyastole (during ventricular systole). In particular, distance between atrial defect and aortic root and inferior vena cava is measured in CT and echocardiography. Atrial defects and closure devices are compared in 3D visualization, before and after closure procedure. Conclusion: This fi rst experience with CT for percutaneous defect closure of the atrium seems promising.

Cardiovascular malformations with intra and extracardiac shunts in adults:

The To review congenital heart diseases with shunts. Background: The prevalence of congenital heart diseases is approximately 1% of all births. Detection of some of them, especially when combined with great vessels' anomalies, may cause some diffi culties using routine diagnostic techniques. Application of MSCT for cardiac imaging is increasing and becoming more precise along with higher resolutions achieved in modern scanners. That enables both accurate visualization of central circulatory system and adjacent anatomical structures. Imaging Findings: Examinations of 30 adult patients with variable cardiovascular defects performed with 8-row and 64-row scanner were processed. Selected group contained: ASD, VSD, patent ductus arteriosus, univentricular heart with transposition of great arteries, corrected transposition of great arteries, Fallot's tetralogy, left and right sided partial anomalous pulmonary venous returns and persistent left superior vena cava. In addition, CT examinations after surgical corrections of some of the defects were presented. Multiplanar and 3D reconstructions were acquired and shown with respect to educational purpose. Conclusion: MSCT allows precise diagnosis of complex cardiovascular malformations and postoperative evaluation, being a valuable tool for imaging even complicated and infrequent anomalies of central circulatory system. Moreover, multiplanar and 3D reformations allow visualization of congenital heart defects as ideal educational material.

Morphological atherosclerotic plaque analysis on coronary artery autopsy specimens using dual source computed tomography, micro computed tomography, and histopathology W. Kristanto, R. Dikkers, P.M.A. van Ooijen, M.J.W. Greuter, T.P. Willems, M. Oudkerk; Groningen/NL (w.kristanto@rad.umcg.nl) Purpose: To compare visualization of atherosclerotic plaques by Dual Source Computed Tomography (DSCT), Micro Computed Tomography (MicroCT) and histopathology. Methods and Materials: Eleven autopsy specimens of human coronary vessels were scanned with MicroCT (Siemens MicroCATII, Siemens Molecular Imaging, Knoxville, Tennessee) without contrast agent and with DSCT (SOMATOM Defi nition, Siemens Medical Solutions, Forchheim, Germany) with contrast agent (mean 250 HU). The images were reconstructed at 48 µm voxel size (MicroCT) and 0.6 mm slice thickness (DSCT). Histopathology analysis was performed afterwards for reference. From the reconstructed images, the morphology of the plaques was compared to the histopathological results. Results: Some calcifi ed spots found by histopathology were detected by DSCT, but were overestimated in size. Some soft plaques observed by histopathology were vaguely shown by DSCT. Smaller calcifi ed plaques and plaque ruptures were observed by histopathology, but could not be detected on DSCT. MicroCT clearly showed small calcifi cations and vessel wall thickening. A lower density structure, suspected as lipid pool, was observed inside one of the large calcifi ed plaques and a possible plaque rupture was also observed in one of the specimens on MicroCT. Conclusion: DSCT tends to overestimate medium and large calcifi ed plaques whereas it misses the small ones. Soft plaques are shown but vaguely. MicroCT shows much more details on plaque morphology, as can be expected by its high spatial resolution. Our fi ndings show that current clinical CT is mainly limited by spatial resolution. Analysis of the fi ndings from MicroCT and histopathology may help interpret the clinically available CT data.

Why do we misinterpret lesions on cardiac CT while compared with catheter coronary angiography? A critical review series collaborated with cardiologists T. Lee, I. (sillyduck@ms11.url.com.tw) Learning Objectives: To understand the limitations and artifacts of CT coronary angiography. To understand when, how and why we misdiagnose in CT coronary angiography. To understand the possible reasons for the discrepancy between CT and catheter coronary angiography. Background: CT coronary angiography is recently a hot topic. With the advent of MDCT, this technique is gradually integrated into the clinical practice. But this technique is so new that the standards of training, interpretation and clinical practice are not established yet. What are the basic requirements of an 'interpretable' scan? When and why do we misinterpret? Are the misinterpretations avoidable? These are important questions we will try to answer by this review series. Procedure Details: We retrospectively review 72 cases that underwent both the 40-detector row CT coronary angiography and catheter coronary angiography. All initial reports and images are critically reviewed by collaboration of two cardiac radiologists and a senior interventional cardiologist. Using catheter coronary angiography as reference, all the misinterpretations are critically discussed. All the lessons learned are summarized with consensus. About the CT aspect, the discussed topics include respiratory motion, heart rate, heart rate stability, arrhythmia, image noise, interpretation skill, post-processing technique, reconstruction phase selection and window settings. Some misinterpretations of catheter coronary angiography are also found during the review process and will be demonstrated and discussed in the exhibit. Conclusion: Most misinterpretations in CT coronary angiography are related to the techniques in interpretation, image acquisition and processing. Most of them are potentially avoidable.

Multidetector Purpose: To show typical anatomic pattern and variance of the left atrium-pulmonary veins complex (LA-PV) studied by 16 slices Multidetector CT (MDCT) in atrial fi brillation (AF) patients candidated to percutaneous ablation. The exact knowledge of this anatomic region is extremely important to increase the effi ciency and effi cacy of the procedure, and to reduce the related complications. Methods and Materials: In the last three years, 65 AF patients (15 females, 50 males) underwent MDCT cardiac examination using retrospective gating and dose modulation with reconstruction of 75% of RR ECG interval. Results: In the patient population, we identifi ed 141 right PV, 11 of which were suprannumerary; 112 left PV, 19 of which common trunk and 1 suprannumerary. In 60% of patients, the anatomic pattern was typical (2 right and left PV) and in the remaining 40% atypical (23% 2 right PV and left common trunk; 2% 3 right PV and 3 left PV; 6% 3 right PV and left common trunk). In the defi nition of branching, MDCT identifi ed 55 branchings of the right inferior PV, 41 of the right superior PV, 4 of the left superior PV, 6 of the left inferior PV and 2 of the suprannumerary veins. Conclusion: MDCT represents a fundamental diagnostic imaging tool in the anatomic defi nition of the PV that is characterized by great variability. Radiologists must be familiar with anatomic variants and understand the importance of these variants to the refering cardiac interventional electrophysiologist. Data was also collected on the extent of coronary artery disease (CAD), peripheral vascular disease (PVD), and the treatment given to that patient. Data regarding presence of associated cardiovascular and cerebrovascular disease in the PVD group were obtained from the patient's medical record. Results: Age and sex distribution were similar in both groups. Prevalence of risk factors in both groups was as follows (CAD/PVD): 77%/68% hyperlipidaemia, 55%/61% hypertension, 47%/69% smoking, 39%/44% positive family history and 17%/36% diabetes. In the PVD group, 42% and 23% had symptomatic CAD and cerebrovascular disease, respectively. In the CAD group, 12% had symptomatic cerebrovascular disease. Coronary disease on investigation was more severe than in comparable studies Conclusion: This study has shown that the prevalence of risk factors and associated co-morbidity are either comparable or higher than studies carried out elsewhere. Higher prevalence of smoking and diabetes was noted in the PVD group. Findings of the coronary and peripheral angiograms and the resulting treatment will be discussed. Learning Objectives: To discuss the acquisition protocol and reconstruction algorithm which provide optimal image quality of bypass grafts and native coronary arteries with Dual-Source CT. To address artifacts and interpretative strategy for CT coronary angiography in patients after bypass surgery. Background: The recently introduced DSCT scanner permits coronary imaging with high resolution (83 ms), which provides improved image quality in patients with higher heart rates when compared to earlier scanner generations. Moreover the entire heart and graft course can be acquired within a single breath-hold of 8 to 12s. Procedure Details: In this exhibit, we provide examples of DSCT coronary angiography in the evaluation of normal and diseased and occluded bypass grafts. Different bypass surgery techniques are discussed and various examples shown. In addition, we address possible artifacts originating from graft orifi ce indicators, surgical clips and sternal wires, and discuss pitfalls in the evaluation of both bypass grafts and native coronary arteries. Conclusion: DSCT allows high-resolution scanning of the entire thorax within a single breath hold. We demonstrate image quality of DSCT coronary angiography in patients with various heart rates after bypass surgery. We discuss the acquisition protocol and reconstruction algorithm, which provide optimal image quality of both CABG and native coronary arteries. Learning Objectives: 1. To modify the standard protocol of coronary imaging studies in order to depict IVS and right ventricle. 2. To recognize different kinesis pattern of IVS related to various cardiac diseases. Background: Regional kinesis alteration of IVS is associated with different cardiac conditions which may have both pathological and physiological meanings of which the most important are the following: a) left bundle branch block that may determine intra-left ventricular asynchrony and may represent an independent predictor of severe cardiac events in heart failure patients; b) pulmonary embolism that increase right ventricle pressure; c) constrictive pericarditis; d) restrictive cardiomyopathies; e) post-operative cardiac surgery. Procedure Details: A 64-MSCT scanner (LightSpeed VCT, General Electric, Milwaukee) was employed, using the following parameters: 64x0.625 collimation, pitch 0.24, 680 mA, 120 kV, rotation time 350 msec.; i.v. iodinate contrast agent was administrated with a double phase injection : 80 cc at 5 cc/sec followed by 20 cc at 4 cc/sec. Beta-blockers were administered to patients with heart rate above 65 beats per minute (bpm). Axial images were then reconstructed at multiple phases covering the cardiac cycle in increments of 5% of the R-R interval between 0% and 95%. After the reformatted images were transferred to a workstation, contiguous multiphase short-axis and long-axis images were generated using semiautomated interactive software (Advantage Windows 4.2, CardIQ III function, GE Healthcare). Conclusion: 64-MSCT is an effective imaging modality in depicting IVS contraction anomalies. Learning Objectives: To understand normal imaging characteristics of contrastenhanced CT images of myocardium and pericardium, together with a great variety of common and more rare pathologic conditions involving these structures. Background: Since the introduction of 16-and especially 64-slice, CT radiologists are increasingly involved in the execution and interpretation of CT images of the heart and coronary arteries. While there is extensive literature on the imaging of the coronary arteries, CT imaging features of the myo-and pericardium have been scarcely reported. Imaging Findings: It is the aim of this pictorial review to familiarize the radiologist with the common presentation on CT examinations of myo-and pericardium, including normal anatomy variations. Furthermore, a wide variety of diseases like myocardium infarctions of different ages, congenital entities like non-compaction cardiomyopathy, pericardial cysts and other pathologies are reviewed. The images are collected from more than 3000 16-and 64-slice cardiac CT examinations gathered between 2003-2006. Conclusion: Pathology in the myocardium and pericardium is frequently encountered during CT examination of the heart and coronary arteries. Solid knowledge of both normal and abnormal presentation of these structures will increase the diagnostic accuracy of the radiologist, as such limiting errors of interpretation. 

The infl uence of heart rate fl uctuation on cardiac image quality and the improvement by combining varispeed scan technique (VST) and multi sector reconstruction algorithm (MSR) J. Liao 1 , Y. Shen 1 , X. Ge 2 , S. Wu 2 , J. Li 1 , J. At 60 and 105 bpm, the image quality with 0.5 s/r was better than the one with 0.6 s/r. But at 85 bpm, the image quality with 0.6 s/r was better than the one with 0.5 s/r. 3. At the higher HR (85 bpm, 105 bpm) and wider HR fl uctuation range, MSR could improve the image quality signifi cantly (p < 0.05). Conclusion: HR fl uctuation is an important reason that degrades the image quality. VST could optimize the matching of rotation speed and HR to improve image quality. MSR could provide the better temporal resolution and it is effective in reducing the infl uence of HR fl uctuation.

MDCT-CA volume rendering/auto track vs. MPR/MIP analysis to assess coronary artery stenosis V. Alaimo 1 , G. Runza 1 , L. La Grutta 1 , M. Galia 1 , G.F. Lo Re 1 , T.V. Bartolotta 1 , F. Cademartiri 2 , M. Midiri 1 ; 1 Palermo/IT, 2 Parma/ IT (valalaimo@libero.it) Learning Objectives: To display as a correct approach to detect coronary artery disease is based on a careful evaluation of coronary tree by using manual track vessel analysis and MPR/MIP reconstructing approach. To demonstrate as the degree of coronary arteries stenosis is infl uenced by different post-processing techniques. Background: Cardiac MDCT is a non-invasive technique to recognize presence of coronary disease, thanks to the capability to identify vessels remodelling and coronary stenosis. In this exhibit, we will describe the use of different post-processing techniques for the assessment of coronary artery stenosis, such as VR/Auto track approach and MPR/MIP conventional assessment, which are compared. Imaging Findings: Post-processing procedures were performed using auto-cage bone removal/auto track and MPR-MIP/manual track vessels analysis. Images obtained with the methods were compaired. Conclusion: VR images of LAD, CRX and RCA, clearly show the non-calcifi ed stenotic tract of the vessels, but often overstimate the degree of stenosis compared with MPR/MIP assessment. Stenosis of the marginal and diagonal arteries with a small diameter are diffi cult to assess with VR and Auto track analysis. The correct approach for an accurate and complete evaluation of coronary tree cannot exclude the vessels analysis by MPR/MIP reconstruction.

Utility of multislice computed tomography with a 64-data acquisition system for four-dimensional volumetric analysis using a pulsating phantom and considering pulsation rate and reconstruction methods N. Funabashi 1 , N. Mizuno 1 , K. Suzuki 2 , M. Terao 2 , K. Nakamura 1 , F. Maeda 2 , M. Uehara 1 , I. Komuro 1 ; 1 Chiba/JP, 2 Tateyama/JP Purpose: To evaluate 64-DAS MSCT (Light Speed VCT, GE) at 0.625 mm slicethickness, 0.35s/rotation, tube 120KV at 400 mA, ECG-gated for 4-D volumetric analysis, we used pulsating phantoms to measure end-diastolic (EDV) and endsystolic (ESV) volume and ejection fraction (EF) to assess reconstruction methods especially for higher pulsation rates.

A pulsating device (AZ-631N, Anzai Medical) with contrast material (300 mgI/dl) diluted 10x with saline was moved at 40-110 to-and-fro movements/min. ECG-gated MSCT was performed x5 per pulsation rate. The EDV and ESV were measured using workstation (Virtual Place Advance Plus, Aze).

The mean EDV and ESV were 98, 97, 97 96, 95, 94, and 101% and 145, 143, 142, 144, 145, 149, 156 and 160%, respectively, compared 

Coronary fl y-through or virtual angioscopy using dual source MDCT data P.M.A. van Ooijen, M. Oudkerk; Groningen/NL (p.m.a.van.ooyen@rad.umcg.nl) Purpose: Coronary fl y-through, or virtual angioscopy (VA), has been studied ever since its invention in 2000. However, its application was limited because of the requirements for an optimal CT scan and time consuming post-processing. Recent advances in post-processing software facilitate easy construction of VA but until now, image quality was insuffi cient in most patients. The introduction of dual source MDCT could prove to enable VA in all patients. Methods and Materials: Twenty patients were scanned using a dual source MDCT (Defi nition, Siemens, Forchheim, Germany) using a standard coronary artery protocol. Post-processing was performed on an AquariusWorkstation (TeraRecon, San Mateo, CA). Length travelled per major branch was recorded in mm together with the time required in minutes. Results: VA could be performed in every patient for each of the major coronary arteries. The mean (range) length of the automated fl y-through is 80 (32-107) mm for the left anterior descending, 75 (21-116) mm for the left circumfl ex artery, and 109 (21-190) mm for the right coronary artery. Calcifi cations and stenoses are visualized, as well as most side branches. Mean time required was 3 min for LAD, 2.5 min for LCx, and 2 minutes for the RCA. Conclusion: Dual source MDCT allows for high quality visualization of the coronary arteries in every patient because scanning with this machine is independent of the heart rate. This is clearly shown by the successful virtual angioscopy in all patients. Potential clinical value of the VA should be determined in the near future. and EF between CT and ILVG were 0.3±126.7 ml, 25.8±40.4 ml, and -21±24%, respectively. In 37 subjects with OMI, the correlation coeffi cients between CT and ILVG for EDV, ESV, and EF were 0.79, 0.84, and 0.60, respectively (all P < 0.01), and the averages±2SD of the differences of EDV, ESV, and EF between CT and ILVG were 8.0±54.1 ml, 28.5±36.7 ml, and -20.5±24.5%, respectively. Conclusion: In all subjects, estimates of EDV, ESV, and EF were signifi cantly correlated between CT and ILVG, but CT tended to underestimate EF. In subjects with OMI, CT tended to overestimate EDV and ESV, and estimates of EF were less correlated between CT and ILVG in subjects with OMI. These discrepancies may be due to capability of CT to estimate LV wall asynergy 3-dimensionally more accurately than ILVG.

Quantitative annual effect of atorvastatin on size and content of noncalcifi ed plaques of coronary arteries following atorvastatin treatment by multislice CT N. Results: Patency was confi rmed in 70% DES (83, 50 and 50% with 3.5, 3, and 2.5 mm diameters, respectively), and in 87%BMS (100, 88, 95 and 69% with 4, 3.5, 3, and 2.5 mm diameters, respectively). Patency of 30% DES (17, 50, and 50% with 3.5, 3, and 2.5 mm diameters, respectively) and 13% BMS (0, 12, 5, and 31% with 4, 3, 5, 3, and 2.5 mm diameters, respectively) could not be confi rmed because of partial volume effects due to small size. 6% BMS revealed a low CT area inside the stents (1 each with 4, 3.5, and 3 mm diameters). 4% BMS revealed total occlusion (1 each with 3.5 and 3 mm diameters). Conclusion: 64-slice MSCT is a non-invasive diagnostic modality with the potential for evaluating patency of DES with a low incidence of restenosis, especially DES with 3.5 mm diameter. However, due to partial volume effects, it remains diffi cult if the lumen is 3 or 2.5 mm. BMS had a thinner slice thickness and bigger lumens, and their patency was easier to evaluate by MSCT. Background: Within the patients with chest pain and overt coronary artery disease, there are a large number of negative fi ndings. A small niche of these patients present with chest pain that mimics coronary artery disease and they may carry unusual fi ndings. In these patients, the diagnostic challenge may be diffi cult using the conventional diagnostic tools (i.e. history, physical examination, ECG, biomarkers, chest X-ray). CT coronary angiography is increasingly applied in the ER settings for the assessment of patients with atypical chest pain because of its high negative predictive value in populations with low-to-intermediate prevalence of disease. A diagnostic spin-off of CT coronary angiography relates to its capability of showing any thoracic fi nding and therefore several different fi ndings, such as non coronary causes of chest pain, may arise (i.e. pulmonary embolism, aortic dissection, pulmonary artery fi stula, coronary fi stula, bronchogenic cyst, pericarditis, oesophageal disease, pulmonary sequestrum, mediastinal masses, etc). Imaging Findings: This exhibit will overview all causes of cardio-thoracic syndrome mimicking coronary artery disease. Examples will be provided with patho-physiological explanation. Conclusion: CT coronary angiography applied to cardio-thoracic syndromes is able to detect all major non-coronary causes of chest pain. For this reason, it is becoming the gold standard for chest pain assessment especially in ER settings.

Coronary artery anomalies at 64-slice coronary CT angiography C. Thilo, P. Costello, U.J. Schoepf; Charleston, SC/US (thilo@musc.edu)

Learning Objectives: The aim of this exhibit is: 1) To review the classifi cation of coronary artery anomalies. 2) To differentiate clinically signifi cant and insignifi cant variations. 3) To illustrate coronary anomalies based on 64-slice coronary CT angiography (cCTA). 4) To emphasize small vessel anatomic variations. Background: The increased use of cardiac CT leads to more frequent detection of coronary anomalies. Improved temporal and spatial resolution of 64-slice CT enables visualization of small anomalies, which have been insuffi ciently described to date. Imaging Findings: The following imaging fi ndings will be reviewed and discussed: Coronary anomalies: Frequency and clinical signifi cance -Normal variants -Benign coronary anomalies -Malignant coronary anomalies -Coronary artery fi stulas -Small vessels of the heart: Anatomy and variants of the sinus node artery, conus branch, septal perforators, etc. Conclusion: 1) Coronary artery anomalies are more frequently detected since the introduction of cCTA. 2) cCTA with 64-slices enhances our knowledge on small vascular anatomy and small vessel variation. 3) In most cases, congenital anomalies are asymptomatic and incidentally detected. 4) In symptomatic patients with suspicion of coronary artery anomalies, cCTA is emerging as the diagnostic modality of choice.

Comparison between iodine and gadolinium-enhanced multidetector CT coronary angiography: Preliminary report P. Carrascosa 1 , C. Capuñay 1 , M. Bettinotti 2 , A. Goldsmit 2 , J. Carrascosa 1 , R. Pissinis 1 ; 1 San Isidro/AR, 2 Capital Federal/AR (patriciacarrascosa@diagnosticomaipu.com.ar) Purpose: To determine the sensitivity (S) and specifi city (Sp) of gadolinium-enhanced CT angiography (Gd-CTA) and iodine-enhanced MDCT (I-CTA) for the detection of signifi cant coronary stenosis compared to digital angiography (DA). Methods and Materials: Eighteen patients with known coronary artery disease underwent Gd-CTA, I-CTA and DA. CTs were performed with a 16-row CT scanner. For Gd-CTA, a volume of 0.4 mmol/kg of body weight of gadolinium was administered. For the I-CTA, a volume of 100 ml of contrast material containing 350 mg/ml of iodine was administrated. The axial images and reconstructions of the coronary tree of both acquisitions were reviewed independently and directly compared. The degree of enhancement, the capability of an adequate delimitation of the coronary tree and the detection of coronary artery disease were evaluated. Both acquisitions determined the presence of plaques and measured the coronary stenosis. Those equal or above 50% where considered as positive fi ndings. Results: Gd-MDCT angiography was successfully completed for evaluation in all patients. Axial and multiplanar reconstruction images showed adequate visualization of the main coronary artery. 

The effects of injection of contrast materials on the heart rate and its fl uctuation in the 16-slice CT coronary angiography Y. Liu 1 , X.Z. Lin 1 , K.M. Chen 1 , Y. Shen 1 , Z. Hao 2 ; 1 Shanghai/CN, 2 Shenyang/CN (lxzmm@yahoo.com.cn) Purpose: To evaluate the effects of contrast medium (CM) injection on the heart rate and its fl uctuation in 16-slice CT coronary angiography (CTCA). Methods and Materials: 140 cases that underwent 16-slice CTCA were included in the study. During calcium scoring and CTCA, waves of electrocardiogram (ECG) were recorded in two fl oppy disks. Values of heart rate were recorded, and the differences between the sequential heart beats (D-HR) were calculated. All cases were classifi ed into three groups according to their heart rate: Group 1: < 60 BPM; group 2: 60-70 BPM; and group 3: > 70 BPM. The ECG data of the three groups were compared statistically. ECG data of all the heartbeats and the fi rst fi ve beats after the CM injection were also compared. Results: 239 ECG were included in total, in which 107 ECG were before CM injection and 132 after. The mean BPM of groups 1, 2 and 3 before CM injection were 56.01, 65.13 and 76.47 BPM and after CM injection were 55.26, 64.71 and 76.24, respectively. Mean D-HR of groups 1, 2 and 3 before CM injection were 3.06, 3.27 and 5.52 BPM and after the CM injection they were 3.42, 4.28 and 6.47, respectively. Mean D-HR of all the heartbeats and the fi rst fi ve beats after the CM injection were 4.44 and 2.76 BPM, respectively. Conclusion: Though the mean heart rate after CM injection was a little lower than that before CM injection, the fl uctuation of heart rate increased after CM injection during the 16-slice CTCA. Shortening the scanning time may decrease the fl uctuation of heart rate. 

To assess the incidence of pulmonary vein stenosis in patients submitted to atrial fi brillation ablation and to increase awareness of this clinical syndrome A. Bajaj, D.T.D. Barnes, P.A. Vlachou, T. Siva, J.J. Entwisle; Leicester/UK (amrita. bajaj@uhl-tr.nhs.uk) Purpose: To assess the incidence of pulmonary vein stenosis in patients submitted to atrial fi brillation ablation and to increase awareness of this clinical syndrome. Methods and Materials: 174 consecutive cases had catheter ablation for atrial fi brillation over a period of two years 2004-2005. These were retrospectively reviewed on the radiology information system to look for any cross-sectional imaging of the thorax (multi-detector row CT/MR) performed within 6 months following the ablation. The images were then retrospectively reviewed to look for pulmonary vein stenosis. Results: Eighteen of the 174 patients had CT/MR within 6 months of the procedure. Six of the 18 cases queried pulmonary vein stenosis on the initial request. Six of the cases were done to evaluate the anatomy for redo procedure. Of the remaining 6, 4 queried pulmonary embolism, 1 queried bronchiectasis and 1 was unclear.

Five patients presented with haemoptysis on the initial request. In 5 patients, the history of ablation was not stated on the radiology request. Six (3.4%) patients had pulmonary stenosis. Left superior pulmonary vein was the most commonly involved. Remaining important radiological fi ndings also seen in the cases of pulmonary vein stenosis were consolidation and lung nodule. Conclusion: Pulmonary vein stenosis after catheter ablation is an important complication associated with signifi cant morbidity. Our series showed a complication rate of 3.8%, with severe stenosis in a still smaller percentage. The reported incidence ranges from 3% to 42%. Radiologist and clinicians should be aware of this condition in patients presenting acutely following ablation. Learning Objectives: 1) To remind of the major features of the most frequent congenital heart diseases (CHD), including atrial septal defect (ASD), ventricular septal defect (VSD), tetralogy of Fallot (TOF), transposition of the great arteries (TGA) and coarctation of the aorta. 2) To expose CT and MR advantages and limits in these indications. 3) To give radiologists clues to better understand clinicians' questions and therefore to answer them better. Background: Because life expectancy of patients with a congenital heart disease (CHD) has improved, thanks to better medical and surgical managements, and thanks too to great improvements in CT and MR imaging, radiologists are more and more faced with these particular conditions. Moreover, as surgical techniques have become more sophisticated and complicated, the need for a precise anatomical description and for functional analyses has become crucial. CT and MRI have these abilities and are complementary. But they also have some drawbacks. Procedure Details: We will illustrate this topic using numerous cases taken from our experience as a CHD care center. All CT exams were performed on a multislice CT, either a 4 or a 64 detectors, whereas MR were performed on a 1.5 T magnet. CT and MR protocols varied, depending upon the congenital heart disease. Conclusion: CT and MRI are powerful tools for the non-invasive evaluation of CHD. Anyone performing these exams has to understand their advantages and limits in order to be able to answer clinicians' questions. 

Immunologic lung diseases other than asthma and collagen-vascular disorders: An electronic teaching fi le C.M. Plank, C. Grosse, A. Koller, L. Stiebellehner, C. Müller-Mang, A.A. Bankier; Vienna/ AT (christina.plank@meduniwien.ac.at) Learning Objectives: To familiarize radiologists with immunologic lung diseases other than asthma and collagen-vascular disorders. To elaborate classical patterns of presentation, clinical history, and radiological features of these disorders.

To propose a systematic diagnostic approach based on clinical and radiological fi ndings. Background: Immunologic lung diseases other than asthma and collagen-vascular disorders include: 1) Lung vasculitides (Wegener's granulomatosis, Churg-Strauss syndrome, hypersensitivity vasculitis); 2) Diffuse pulmonary hemorrhage; 3) Eosinophilic lung disease (acute and chronic eosinophilic pneumonia, drug-induced lung disease); 4) Extrinsic allergic alveolitis; and 5) Amyloidosis. Although these diseases are relatively common, there is little awareness of their etiology, their underlying pathomechanisms, their classifi cation, and their clinical and radiological manifestations. The purpose of the proposed electronic teaching fi le, therefore, is to elaborate a comprehensive diagnostic approach based on combined clinical and imaging fi ndings. Imaging Findings: The CT imaging fi ndings of the diseases will be the central part of our presentation. The CT fi ndings will be correlated with pathological specimens, and combined to typical clinical histories and presentations. The overall structure will follow most recent classifi cations of immunologic lung diseases other than asthma and collagen-vascular disorders. The format of the electronic teaching fi le will allow easy navigation through the information and provide an integrative comprehensive approach. Conclusion: In the appropriate clinical setting, CT fi ndings in immunologic lung diseases other than asthma and collagen-vascular disorders are suggestive of the underlying disorders and allow in making the correct diagnosis with a reasonable level of confi dence.

Radiologic-pathologic correlations between intratumoral macroscopic and microscopic components in lung neoplasms E. Quaia; Trieste/IT (quaia@units.it)

Learning Objectives: To describe those intratumoral components in lung neoplasms that are depicted by imaging. Background: Different intratumoral components in lung neoplasms, which were evident at macroscopic and/or microscopic analysis, may be recognized in un-enhanced and contrast-material-enhanced computed tomography (CT) images. Imaging Findings: Seventy lung masses (4-8 cm in diameter) in 70 patients (44 males, 26 females, mean age ± SD, 60 ± 15) were imaged by CT before and 25 seconds after intravenous injection of iodinated contrast agent (iodine 300 mg/mL; 150 mL; i.v. bolus injection). Surgical/bioptic/autoptic specimens were analysed by macroscopic and microscopic/histologic analysis (hematoxylin and eosin staining, x20-x40 magnifi cation), and two observers identifi ed in consensus those intratumoral components that were depicted by CT images. Macroscopic components:

(1) internal colliquative necrosis in squamous cell carcinomas (n=30) appeared hypodense at un-enhanced CT, and without enhancement after contrast injection; (2) fi brotic component in adenocarcinomas (n=5) manifested as peripheral strands; (3) bronchiolo-alveolar carcinomas (n=2) presented as diffuse/confl uent parenchymal consolidations; (4) coagulative necrotic and haemorrhagic changes in small cells (n=15) and anaplastic carcinomas (n=10), which appeared, respectively, hypodense and hyperdense at un-enhanced CT, and without enhancement after contrast administration; (5) 

Air-leak syndromes in hematopoietic stem cell transplant recipients with chronic GVHD-related bronchiolitis obliterans: Thin-section CT fi ndings E. Granell, R. Guerrero, T. Franquet, A. Giménez, A. Hidalgo, F. Plancarte;

Purpose: To determine the incidence and the thin-section CT fi ndings of air-leak syndromes in a large group of hematopoietic stem cell (HSC) transplant recipients with chronic graft-versus host disease (cGVHD) related bronchiolitis obliterans (BO).

A retrospective review of the medical records and imaging fi ndings identifi ed 158 allogeneic HSC transplant recipients with a proven diagnosis of cGVHD between January 1999 and December 2004. Of the 158 transplant recipients, 9 had air-leak syndrome and proven cGVHD. The patients were 8 men and 1 woman ranging in age from 19 to 45 years (mean age, 28 years). The thinsection CT scans were retrospectively reviewed by two thoracic radiologists for the presence, appearance, and distribution of abnormalities. Results: All cases were allogeneic HSC transplant recipients with cGVHD who acquired new respiratory symptoms and/or radiologic abnormalities. Nine cases of air-leak syndrome occurred during the analyzed study period, for a 2-year estimated cumulative incidence of 2.1%, whereas its prevalence was 5.7%. Among all the patients, pneumomediastinum (n=6) and pneumothorax (n=6) accounted for the majority of air-leak syndromes in our series; the remainder were due to subcutaneous emphysema (n=3) and pulmonary interstitial emphysema (n=2). A combination of different air-leak syndromes was observed in 6 cases. In all cases there existed an association between air-leak syndromes and cGVHD-related BO. Conclusion: Air-leak syndromes represent an uncommon late complication in HSC transplant recipients related to cGVHD and BO. 

The many faces of bronchioloalveolar carcinoma: A radiologic-pathologic pictorial review D. Chourmouzi, E. Papadopoulou, K. Xinou, T. Zaraboukas, A. Drevelegas; Thessaloniki/GR (dchourm@hol.gr)

Learning Objectives: To describe the pathologic and radiologic types of Bronchioloalveolar carcinoma (BAC). To present the imaging features of each type of BAC. To outline the main differential diagnosis. To emphasise the role of imaging evaluation in treatment and follow-up. Background: Bronchioloalveolar carcinoma (BAC) is classifi ed as a subset of lung adenocarcinoma but has a distinct clinical presentation, tumor biology, response to therapy, and prognosis compared with other subtypes of non-small-cell lung carcinoma (NSCLC). It is characterized by growth along alveolar septae without evidence of stromal, vascular, or pleural invasion. Nonmucinous bronchioloalveolar carcinoma tends to be more localized and has a lower frequency of bronchogenic spread than mucinous bronchioloalveolar carcinoma. BAC has received increasing attention in recent years due to its increasing incidence and its rate of sensitivity to epidermal growth factor-tyrosine kinase inhibitors (EGFR-TKIs). Imaging Findings: At computed tomography (CT), the single nodular form appears as a peripheral nodule or localized ground-glass attenuation with or without consolidation, frequently associated with bubble like areas of low attenuation and open bronchus signs. The lobar consolidative form may demonstrate the CT angiogram and open bronchus signs. The diffuse nodular form appears as multiple nodules or areas of ground-glass attenuation or consolidation. Conclusion: Understanding the radiologic fi ndings of bronchioloalveolar carcinoma on the basis of various morphologic and growing patterns is essential in the initial evaluation of patients with BAC. High-resolution lung CT-scan is necessary to evaluate pulmonary involvement. Imaging evaluation is also essential to assess therapeutic response and follow-up.

Pattern recognition in lobar collapse: Can you read the signs? E. Sonnex, R.A. Coulden; Leicester/UK (emer@prdg.demon.co.uk) Learning Objectives: To understand plain fi lm appearances and recognise the patterns of lobar collapse. These fi ndings are fully explained and corroborated by a 3-dimensional CT reconstruction. Background: The diagnosis of lobar collapse is the 'bread and butter' of chest radiology but as 3-D imaging takes over, plain fi lm reporting skills are being lost. Procedure Details: We describe the classic patterns of lobar collapse on the plain chest radiograph with the aid of CT correlation to explain the appearances of: Collapse and why it looks the way it does; How to use the silhouette sign; The causes of collapse; The features of collapse. Conclusion: Accurate diagnosis is based on recognised patterns. This presentation uses 3-D CT images to explain the recognised patterns of collapse in plain chest radiographs. (DAD) . TRALI, the transfusion related acute lung injury is an uncommon complication of allogenic blood transfusion typically manifested by bilateral oedema, dyspnea, hypoxemia, fever and hypotension, in presence of a normal cardiac function. The main patterns are pulmonary infi ltrates and eosinophilia, acute pulmonary oedema and upper airway obstruction from laryngeal oedema. Some drugs can also induce severe ALI, such as valproic acid in treatment of neurological epilepsy that can induce alveolar haemorrage or gemcitabine during treatment for breast cancer. Imaging Findings: Acute Lung Injury presents radiological and CT challenges. The chest X-ray demonstrates bilateral infi ltrates without signifi cant increase in cardiac size or vascular pedicle. CT demonstrates ground glass attenuation (a hazy increase in the lung attenuation with preservation of bronchial and vascular margins) in the middle regions and consolidation (increase in lung attenuation that obscures the broncho vascular margins, but the bronchogram sign can be present).

The cyto/histological patterns of different ALI stages explain the imaging features.

The organic dust: Radiographic and high resolution CT fi ndings of hypersensitivity pneuomonitis Z. Khaleel, R. Lavakumar, C. Viswanathan, G. Avery, N. Kennan; Hull/UK (ziyadlk@hotmail.com)

Learning Objectives: To illustrate Pathogenesis of hypersensitivity pneuomonitis (HP). To demonstrate the natural history and physical fi ndings in HP. To defi ne and review the radiographic and HRCT appearances of HP. Background: Hypersensitivity pneuomonitis, also known as extrinsic allergic alveolitis, is an infl ammatory lung disease in which inhalation of certain organic antigens repeatedly induces immunologically mediated reaction with granulamtous tissue formation. The targeted lung structures are the distal bronchioles and the alveoli. Imaging Findings: We will be reviewing the radiographic and the HRCT fi nding in the clinical subtypes of HP. 1) Acute phase: air-space opacifi cation with lower lobe predominance on radiographs and the fi ne nodules and diffuse alveolar consolidation on HRCT. 2) Subacute Phase: fi ne reticulonodular pattern on radiographs and ground glass opacities with centrilobular nodules on HRCT. 3) Chronic Phase: coarse reticulation with upper lobes predominance on radiographs and intraseptal and interseptal thickening, honeycombing and traction bronchioectasis on HRCT.

The defi nitive diagnosis of HP relies on a constellation of clinical, radiological, and laboratory fi ndings. Although the imaging fi nding of HP can be nonspecifi c, certain pattern particularly on HRCT would strongly suggest the diagnosis and facilitate prompt management of the disease.

Diffuse granulomatous lung diseases: High-resolution CT and pathologic fi ndings T. Franquet 1 , N.L. Müller 2 , T.V. Colby 3 ; 1 Barcelona/ES, 2 Vancouver, BC/CA, 3 Scottsdale, AZ/US (19429tfc@comb.es) Learning Objectives: To illustrate HRCT fi ndings of the most common granulomatous disorders of the lung, and to present a working differential diagnosis based on pathologic -radiologic correlation. Background: Diffuse granulomatous lung diseases are a group of lung diseases in which granulomas are an important component of the histologic fi ndings. The term granuloma has been used historically for all reactions rich in histiocytes and mononuclear cell infl ammation; more recently the term has been restricted to cases showing cohesive epithelioid histiocyte clusters usually with associated giant cells (i.e. sarcoid-like granulomas). We use the more restricted defi nition of granuloma in this review, but also include for completeness entities for which the term granuloma has been used historically. Imaging Findings: Depending on the anatomic location and histologic characteristics of the abnormalities, diffuse granulomatous lung diseases may result in several CT patterns: a) nodules greater than 1 cm in diameter, b) small nodules, c) centrilobular nodules and branching lines (tree-in-bud pattern), d) bronchiolocentric infi ltrates, e) ground-glass opacities and consolidation, and f) low-attenuation and mosaic perfusion. Conclusion: This review presents an approach to the differential diagnosis of pulmonary granulomatous disorders based on their HRCT features and compares the HRCT with the pathologic fi ndings.

in the future could help the quantifi cation of these disorders. Conclusion: MDCT offers a new approach to the study of diffuse lung cystic disease. It allows a better characterization of the lesions and an easier visualization of the regional distribution of the cysts.

Four-dimensional multislice helical CT of the lung: Comparison of retrospectively gated and static images in an ex-vivo system J. Purpose: To analyze the image quality of retrospectively gated helical CT based on a comparison with static scans. Methods and Materials: Five porcine lungs were infl ated inside a dedicated chest phantom and prepared with 8-14 nodules of ~1 cm. A water-fi lled diaphragm simulated contractions at a frequency of 8/min. Images were acquired in a dynamic mode with a pitch of 0.1 (slice collimation 24x1.2 mm, rotation time 1s, slice thickness 1.5 mm, increment 1 mm). Static scans at 0/25/50/75/100% inspiration were obtained with the same protocol, but without respiratory motion. The visual evaluation of image quality was based on multiplanar reformations of the 3D-data sets.

Stepladder-artifacts, partial projection artifacts and noise were judged semiquantitatively by two independent observers for the upper, middle and lower parts of the lung. Scores of 0-3 were given for absent, minimal, large and diagnostically relevant artifacts. Results: Partial projection effects were only present in the dynamic scans (average artifact scores: 1.33). Stepladder artifacts were prominent in dynamic series but also visible on static scans. Both artifacts were less prominent in end-in-and end-expiration and predominated close to the. Image noise predominated close to the diaphragm independently from the dynamic condition. A score of 3 was given 9 times (7/9 for kymographic artifacts), all for the region close to the diaphragm.

The realistic ex-vivo study with direct comparison of retrospectively gated and static scans shows tolerable artifacts of retrospective respiratory gating and confi rms the high quality of 4D-CT. 

The acute lung injury (ALI): A clinico-radiological correlation S. Piciucchi 1 , C. Learning Objectives: 1) To demonstrate the imaging appearances of the respiratory complications of rheumatoid arthritis, systemic lupus erythematosus, mixed connective tissue disease, progressive systemic sclerosis, dermatomyositis, polymyositits and Sjogren's syndrome. 2) To discuss the imaging features suggestive of each of the above conditions and the diagnostic pitfalls. Background: The connective tissue diseases are autoimmune multisystem conditions that can affect the lungs. All components of the respiratory system including pleura, alveoli, interstitium, lymphatics, airways and vasculature can be involved. Although there is a great deal of overlap between the imaging fi ndings in these conditions, there are features that can point the radiologist towards a particular diagnosis. Imaging Findings: Patterns of respiratory involvement include pleural effusion or thickening, organising pneumonia, usual interstitial pneumonia (UIP), nonspecifi c interstitial pneumonia (NSIP), bronchiectasis, lymphoid interstitial pneumonia, lymphoma, obliterative bronchiolitis and nodules. Acute pathologies such as alveolar haemorrhage and pulmonary embolism are also seen. These and others are shown on plain radiographs and CT images.

The purpose of this exhibit is to show the wide spectrum of pleuropulmonary manifestations of connective tissue disease, and to point the radiologist towards a more specifi c diagnosis based on the imaging fi ndings.

Paraquat poisoning of the lung: Initial and follow-up thin-section CT fi ndings in relation to ingestion amount of the paraquat M. Park 1 , S. Song 1 , S. Park 2 ; 1 Uijeongbu/KR, 2 Seoul/KR (namaste-india@hanmail.net) Purpose: To evaluate the patterns, distribution, and extent in relation to the ingestion amount of paraquat poisoning and evaluate the temporal lung changes on thin-section CT (HRCT) scans.

The study included 15 patients with urine-positive paraquat kit and pulmonary abnormalities in HRCT scans. Scans after hemodialysis were assessed for the presence, extent, and distribution of pulmonary abnormalities. Six of the 15 patients, underwent follow-up CT scanning 5-20 days after initial CT.

The abnormal fi ndings on the initial HRCT scan consisted of ground-glass attenuations (n=9), consolidations (n=9), irregular lines (n=9), nodules (n=2), traction bronchiectasis (n=2), pleural effusion (n=4), and pneumothorax (n=1). The most common predominant fi nding that has the largest extent was ground-glass attenuation (n=7). On initial CT scan, the lesions showed bilateral (n=9), lower (n=6) and subpleural (n=6) zonal predominancy. The extent of lung involvement was well correlated to the amount of paraquat ingestion. The follow-up CT was performed in six patients. The ground-glass attenuation might be improved in extent (n=2) or progressed to consolidation (n=2). The new parenchymal abnormalities such as traction bronchiectasis and architectural distortion developed in the remaining two patients. Conclusion: In paraquat poisoning, the most predominant fi nding at initial presentation was ground-glass attenuation and it was bilateral, lower and subpleural in distribution. The extent of lung involvement was well correlated to the amount of paraquat ingestion. On follow-up CT, fi brosis such as traction bronchiectasis and architectural distortion might develop. Background: Lymphomatous involvement of the lung is often asymptomatic or has non-specifi c symptomatology, thereby making diagnosis diffi cult. Cavitating pulmonary lymphoma is a rare entity in both primary and secondary pulmonary lymphoma. Diagnosis if also often hindered as infection (including superimposed infection), granulomatous disease, primary and secondary carcinomas, and drug reactions may have similar radiological fi ndings. Imaging Findings: From our experience with a number of cavitating pulmonary lymphoma patients and a review of literature, we will provide a diverse review of its pathophysiology, clinical and radiological presentations (location, distribution), and appearances (wall features, progression, and response to treatment). Conclusion: This exhibit will provide an informative thorough guide and review of pulmonary lymphoma, its rare cavitating form, highlighting its presentation, radiological features, and progression, and distinguishing aspects from other cavitating lung pathologies.

Idiopathic interstitial lung disease: An analysis of the main radiological fi ndings. An integrated clinical, radiologic and histologic approach to diagnosis M. Prieto del Rey, X. Gallardo Cistare, E. Castaner Gonzalez, J. Mata Duaso, I. Delgado Alvarez, S. Perez Aguilera; Barcelona/ES (mprieto@cspt.es)

Learning Objectives: To describe and illustrate the principal radiological and histological fi ndings for idiopathic interstitial lung diseases. To explain a strategy for the diagnosis of different types of idiopathic interstitial disease and determining their severity and prognosis. Background: We review the radiological fi ndings for idiopathic interstitial lung diseases, grouped according to the American Thoracic Society/European Respiratory Society International Multidisciplinary Consensus Classifi cation (ATS/ERS IMCC) of 2001 into: usual interstitial pneumonia, non-specifi c interstitial pneumonia, desquamative interstitial pneumonia, respiratory bronchiolitis interstitial lung disease, cryptogenic organizing pneumonia, acute interstitial pneumonia, and lymphocytic interstitial pneumonia. Imaging Findings: We present representative cases of each of the seven ATS/ERS IMCC categories, describing the clinical, radiological and histologic fi ndings. We provide high-resolution CT images showing the most characteristic fi ndings for each entity and discuss the differential diagnosis. Conclusion: Careful and thorough evaluation of the distribution, extension, and evolution of the radiological fi ndings together with the relevant clinical information enables a strategy to orient the diagnosis of the different types of idiopathic interstitial disease, their severity, and clinical prognosis. The diagnosis of interstitial lung diseases requires an integrated, dynamic evaluation of the clinical, radiological, and histological fi ndings. High-resolution CT is an important tool in the diagnostic work-up of diseases that affect the pulmonary interstitium. Learning Objectives: This poster should give an overview about the CT scan fi ndings and differential diagnosis of diverse pulmonary fungal infections in immunocompromised patients. Pneumonias caused by aspergillus, cryptococcus, candida, histoplasma, mucor and geotrichum capitatum are illustrated. Background: The importance of pulmonary fungal infections has increased substantially during the last decades, occurring in patients with neutropenia caused by malignancies, solid organ or stem-cell-transplantation, chemotherapy, corticosteroid-therapy or HIV-infection. Because of unspecifi c clinical symptoms and the high morbidity and mortality of these infections, an early and non-invasive diagnose is very important. Imaging Findings: Pulmonary aspergillosis comprises a broad spectrum of disorders. Allergic broncho-pulmonary aspergillosis (ABPA) is typically associated with upper lobe consolidations, mucous-plugging and central bronchiectasis. Semi-invasive aspergillosis is characterized by progressive upper lobe consolidation that may cavitate and harbor mycetomas. The CT halo-sign and, later in the disease, the air crescent sign are characteristic fi ndings of invasive aspergillosis. Cryptococcosis may manifest as a solitary lung mass, as multiple nodules or as segmental or lobular consolidations. In patients with candidiasis, air-space consolidation is most commonly seen with a lower lobe distribution. Histoplasmosis presents with diffuse nodules, small linear opacities or focal or patchy areas of consolidation. The radiological manifestations of mucor mycosis can mimic those of invasive aspergillosis. Geotrichum capitatum can present with bilateral non-cavitated nodules, consolidations and ground-glass-opacity.

The CT fi ndings of fungal diseases may overlap. However, the knowledge of the various radiological appearances of fungal infections in combination with the patient's immunologic status allows narrowing of the differential diagnosis. . Pleural effusion was only seen in 5 patients (13%). Seventeen patients (22%) had single lobe involvement and the rest had multiple lobe involvement. In patients with single lobe involvement, 50% had the right upper lobe involved. In patients with multiple lobe involvement, 39% had all the lobes involved. Apical involvement was seen in 16 patients (41%). There was a very high mortality; 21 patients (54%) did not survive. No signifi cant correlation can be made with the chest radiograph fi ndings and the outcome and duration of symptoms. Conclusion: Chest radiograph fi ndings in patients with melioidosis are very variable. It is also not frequently associated with cavitations and apical involvement, which were frequently seen in patients with pulmonary tuberculosis. The fi ndings may mimic other pulmonary infections.

Infl ammatory myofi broblastic tumor of the lung: CT -pathology correlation S.J. Theodorou 1 , D.J. Theodorou 1 , Y. Kakitsubata 1 , K. Nabeshima 2 , S. Kakitsubata 2 , S. Tamura 2 , P.J. Friedman 1 ; 1 San Diego, CA/US, 2 Miyazaki/JP Purpose: Infl ammatory myofi broblastic tumor of the lung is a rare, benign pseudotumor. The purpose of this study was to describe the CT fi ndings of infl ammatory myofi broblastic tumor of the lung with histopathologic correlation. Methods and Materials: CT images were obtained in 8 patients submitted to our institution over a 9-year period. There were 5 male and 3 female patients, with an age range of 22-73 years (mean age of 55 years). The presenting symptoms were chest pain and cough in 2 cases. For 6 cases, myofi broblastic tumor was an incidental fi nding on chest radiographs. Histopathologic fi ndings were correlated with the imaging fi ndings in all cases. Results: On radiographs and CT images, an ill-defi ned mass or nodule was seen in 5 patients (6 lesions), and a well-defi ned lesion was present in 3 patients (3 lesions). Seven lesions were peripheral, and 2 were centrally located. During CT, 5 lesions were of heterogeneous attenuation, and 4 were homogeneous. Increased perilesional parenchymal abnormalities, which were caused by peribronchial infl ammatory infi ltrates, were seen in 3 cases. The predominant histopathologic feature was organizing pneumonia type in 3 cases, lymphoplasmacytic type in 3 cases, and both organizing pneumonia and lymphoplasmacytic type in 2 cases. Variable degree of fi brous histiocytoma type was noted in all cases. Conclusion: Because of variable imaging features, myofi broblastic tumor of the lung is often misdiagnosed as lung cancer. CT fi ndings combined with certain histopathologic features can suggest specifi c diagnosis. Learning Objectives: To illustrate radiological fi ndings of asbestos-related disease (ARD) involving pleura and lung parenchyma with chest radiographs, conventional CT and High Resolution CT. To emphasize diagnostic features enabling differentiation from benign and malignant lung masses associated with asbestos exposure. Background: Asbestos has been recognised as a potential hazard since the 1940s. ARD is an occupational disease with a long latency period. Our population had a great number of shipyard workers in contact with this dust. A long-term-follow-up of these workers is necessary. Procedure Details: ARD comprises from pleural effusion and pleural plaques to asbestosis, term reserved to interstitial fi brosis, benign masses and malignant lung masses including mesothelioma and bronchogenic carcinoma. Plain fi lms are used to identify presence and extension of asbestos related pleural and lung disease. Conventional CT has been shown to be much more sensitive than chest radiographs in demonstrating these changes and can also identify fi ndings of parenchimal fi brosis such as pulmonary arcades, subpleural lines, parenchimal bands, reticulation and honeycombing. In addition, HRCT can demonstrate thickened interlobular and intralobular lines. Finally, this review will highlight typical characteristics that allows a specifi c diagnosis to determine benign and malignat lung masses, and will focus on spectrum of pseudotumor lesions including round atelectasis, fi ssural pleural plaques and mass-like fi brotic sheets. Conclusion: Rates of ARD remain high in our population due to past occupational exposure and long latency period. Typical imaging features of ARD are described, with special attention to lesions that can mimic neoplastic masses. 

Malignant mesothelioma: Pictorial review of radiological-pathological correlation S. Narayanaswamy, P. Rao, A. George; Plymouth/UK (arunagag2003@yahoo.com)

Learning Objectives: To illustrate the spectrum of imaging and histological appearances, and to discuss the advantages and limitations of these investigations in the diagnosis and follow-up of patients with malignant mesothelioma. Background: Malignant mesothelioma is a highly aggressive tumour with an incidence progressively increasing with time. Malignant mesothelioma has got a grim prognosis attributable to the late detection of the disease. The diagnosis is based on a combination of clinical history, radiological appearances and histology. Despite all these modalities, diagnosis remains a challenging task to the medical profession as symptoms, imaging and the histological features often mimic other pathologies. Imaging Findings: Computed tomography, magnetic resonance imaging, PET and histology play an important role in the diagnosis and staging of malignant mesothelioma. The spectra of radiological abnormalities noted are pleural effusion, plerual thickening, calcifi ed pleural plaques, interlobar fi ssural thickening, contracted ipsilateral hemithorax, evidence of local and distant metastasis. Histologically, it is divided in to 3 distinct types, 1) Epitheliod (60%), 2) Sarcomatoid (15%) and 3) Biphasic (25%). We present a pictorial review of all these distinct radiological and histological appearances, and also discuss briefl y the importance of these features in the diagnosis and staging of malignant mesothelioma. Conclusion: A good understanding of the radiological and histological appearances is important as this will simplify and fasten the process of diagnosing malignant mesothelioma, enabling a larger number of patients to be diagnosed in the initial stages and undertake more successful treatment options.

Feasibility of micro-computed tomography in quantifi cation of murine bleomycin-induced lung fi brosis in in-vivo and postmortem conditions: Correlation with pathologic score H. Lee, J. Goo, J.-G. Im, K.-R. Son, C. Lee, C. Park, E. Chun; Seoul/KR (rosaceci@dreamwiz.com)

Purpose: Bleomycin-induced lung fi brosis (BILF) is an animal model of pulmonary fi brosis. The aims of this study were: (1) to quantify BILF using micro-CT in in-vivo and postmortem conditions and (2) to correlate the micro-CT scores with pathologic ones. Methods and Materials: After intratracheal instillation of bleomycin in eight mice, in-vivo baseline and 2 weeks (2w) (n=3), 4 weeks (4w) (n=3), or 8 weeks (8w) (n=2) follow-up micro-CT (SkyScan 1076; SkyScan, Belgium) in in-vivo and immediate postmortem state were performed with 35 µm spatial resolution. On micro-CT, ground-glass opacities, consolidation, reticular opacities, honeycombing, and bronchial dilatation were scored. Pathologic scores including infl ammation, parenchymal fi brosis, and airway fi brosis were obtained. Spearman's correlation analysis to correlate micro-CT and pathology, Kruskal Wallis with Duncan test to compare the 2w, 4w, and 8w groups, and Wilcoxon signed rank test to compare in-vivo and postmortem micro-CT were performed. Results: Consolidation score in both of in-vivo (rho=0.44, p=0.01) and postmortem (rho=0.45, p=0.01) showed correlation with infl ammation score. Score of bronchial dilatation in in-vivo (rho=0.49, p=0.02) and postmortem (rho=0.56, p=0.001) showed correlation with airway fi brosis score. In 2w group, consolidation score was higher than in 4w or 8w (p=0.03). In 4w and 8w groups, score of bronchial dilatation was higher than in 2w (p=0.02). Only consolidation score of micro-CT was higher in in-vivo than in postmortem (p=0.04), and other scores showed no difference.

The scores of micro-CT and pathology were well correlated. The results of quantitative assessment in in-vivo and postmortem state were nearly comparable. Left-sided injuries are more frequent, the posterolateral aspect of diaphragm being the most common site of rupture. The preoperative diagnosis is often diffi cult because DR may be overlooked due to associated thoracoabdominal lesions. If the diagnosis is missed, intrathoracic herniation of abdominal organs may occur. Subsequent gastrointestinal strangulation/obstruction will have a mortality rate of up to 50%. Supine chest radiograph remains the initial screening tool after blunt trauma. Helical CT, particularly multidetector-row scanners, allows more accurate analysis of the diaphragm, with the subsequent improvement in diagnosis. Imaging Findings: We reviewed chest radiographs and helical CT scans of 10 patients with surgically proved blunt DR. 100% were left-sided. We describe specifi c chest radiographic fi ndings and several CT signs indicative of DR, such as intrathoracic herniation of abdominal content, dependent viscera sign, collar sign, discontinuity of the diaphragm, absent diaphragm sign, and diaphragmatic thickening. Five patients showed delayed presentation, 3 of them with severe complications: 2 intrathoracic gastric volvulus, 1 transverse colonic strangulation/obstruction. Conclusion: DR usually requires prompt surgical repair to avoid delayed complications. Diagnostic tools include chest radiograph and helical CT. Familiarity of radiologists with diaphragmatic anatomy and radiology of DR is required to guide the management of polytraumatized patient.

Fibrosing mediastinitis -the spectrum of contrast-enhanced CT fi ndings A. Devaraj, N. Griffi n, A.G. Nicholson, S. Padley; London/UK Learning Objectives: To illustrate the spectrum of CT fi ndings of fi brosing mediastinitis. Background: Fibrosing mediastinitis is a rare condition characterised by excessive fi brous tissue deposition within the mediastinum. It may present as either an idiopathic condition or as a consequence of an underlying process such as TB or histoplamosis. Procedure Details: We retrospectively reviewed the clinical, pathological and imaging fi ndings on 12 cases of fi brosing mediastinitis obtained from our database from 1992 to 2006. Fibrosing medisatinits diffusely infi ltrated the mediastinum in 5 patients and was localized in 7. Eleven of 12 cases had narrowing of mediastinal structures, including 5 with pulmonary artery narrowing (41.6%), 4 with bronchial narrowing (33.3%), 3 with tracheal narrowing (25%) and one with narrowing of the pulmonary vein (8.3%). The presenting complaint was often associated with compression of a relevant mediastinal structure. The disease was considered idiopathic in 7 cases (58.3%) with a demonstrable aetiology in 5 cases (41.6%). Eight out of 12 patients (66.6%) had additional pulmonary fi ndings on CT, including all patients with a known aetiology. Conclusion: Obstruction of vital structures by fi brosing mediastinitis frequently gives rise to complications and is accurately illustrated by contrast-enhanced CT. There is a high incidence of concomitant pulmonary fi ndings, in particular when an identifi able aetiology is present. 

Congenital bronchial atresia: Imaging fi ndings and endoscopic correlation Y. Pallardó-Calatayud 1 , E. Castañer-Gonzalez 2 , A.J. Revert-Ventura 1 , J. Camps-Herrero 1 , A. Caño-Gomez 1 , E. Mollá-Olmos 1 ; 1 Alzira/ES, 2 Sabadell/ES (ypallardo@hospital-ribera.com) Learning Objectives: To describe and illustrate the characteristic imaging fi ndings of this rare entity and provide guidelines for its diagnosis. To show the correlation between imaging and endoscopic fi ndings. Background: We retrospectively studied12 patients (7 m and 5 f; mean age: 36.7 yrs). All patients underwent chest X-ray and CT and 3 also underwent MRI. All patients underwent bronchoscopy and clinical follow-up. Imaging Findings: Chest X-ray fi ndings were branching tubular opacity (n=7), nodular opacity (n=3), consolidation (n=3), distal parenchymal hyperinfl ation (n=3), and parenchymal translucency (n=8). CT showed a mucous plug in all cases (n=12), with (n=3) or without air (n=9), severe stenosis of a segmental bronchus (n=11) with surrounding hyperinfl ation in 10 of these. Five patients were studied with a 4-row multidetector CT. Learning Objectives: To familiarize with fetal thoracic MRI in order to be able to recognize normal lung images and the most common thoracic abnormalities. To know the MR indications for the diagnosis of fetal thoracic abnormalities. Background: Ultrasonography is the primary imaging modality for prenatal assessment of fetal abnormalities. Limitations of US include restricted fi eld of view, dependence on the skills of the operator and the diffi culty to obtain quality images due to maternal obesity or oligohydramnios. In Spain, prenatal US is usually performed by gynaecologists rather than radiologists, and our experience is scarce. When a pulmonary fetal anomaly is detected, different options should be considered, such as in utero surgery, early neonatal surgery or therapeutic abortion, depending on the severity of the abnormality and the availability of a specialized hospital. It is fundamental to establish a precise antenatal diagnosis and the cases where US is inconclusive and doubts arise, must be solved by other reliable imaging modality. MR is safe during pregnancy, and the development of ultrarapid T2-weighted sequences makes it suitable for confi rming US fi ndings. Imaging Findings: We present our experience in fetal thoracic MRI describing the characteristic imaging features of the normal lung and the thoracic abnormalities studied: congenital diaphragmatic hernia (4), congenital cystic adenomatoid malformation (3), pulmonary sequestration (2) and situs ambiguous with asplenia (1). Conclusion: MRI is the best choice for confi rming thoracic fetal anomalies when US is not conclusive. As radiologists, we must be familiar with its use and with the basic imaging features of these pathologies. The diaphragm is a musculotendinous structure that separates the thoracic and abdominal cavities. MRI offers multiplanar capabilities and good tissues contrast resolution. Review the anatomy and diaphragmatic and paradiaphragmatic processes and its appearances in MRI. Emphasis will be placed on diaphragmatic hernia and traumatic pathology. Imaging Findings: To assess hernias and their contents is the most common indication for diaphragmatic MRI and coronal and sagital. T1-Weighted offers an optimal visualisation of the hypointense diaphragm to evaluate the anatomy. MRI also provides tissues characterization of the hernia contents. MRI can be useful in evaluating for transdiaphragmatic extension of disease, primary or metastatic diaphragmatic or juxtadiaphragmatic tumors. Conclusion: MRI of the diaphragm permitted to evaluate small lesion or hernia anatomy and it can answer clinical diagnostic questions with important management implications that others studies of imaging cannot. Knowing normal and abnormal processes allows for the best diagnosis.

Assessment of diaphragmatic motion after lung resection using magnetic resonance imaging R. Takazakura, M. Takahashi, N. Nitta, K. Murata, N. Tezuka, S. Sawai, S. Fujino; Otsu/JP (rtryu@belle.shiga-med.ac.jp) Purpose: To quantitatively assess the impairment of diaphragmatic motion after lung resection using magnetic resonance imaging.

In 44 patients (29 males and 15 females, mean age: 62.2 years) with lung cancer, diaphragmatic motion was measured during maximal deep slow breathing using a spoiled gradient-recalled-echo sequence before and after lung resection. The study group consisted of 34 patients who were examined using a 1.5-T unit in the supine position and 10 patients using a vertically open 0.5-T unit in both the sitting and supine positions. The infl uence of surgery sites and postures of the patients on the diaphragmatic motion after lung resection was investigated. The protocol of this study was approved by the Institutional Review Board. We received written informed consent from all subjects. Results: In all cases after the lung resection, the diaphragmatic motion of the operated side signifi cantly decreased (p < 0.001) and that of the non-operated side increased signifi cantly (p = 0.045). After left upper lobectomy and right bilobectomy, the diaphragmatic motion of the operated side decreased signifi cantly (p < 0.001), and that of the other side increased signifi cantly (p < 0.001). After right middle lobectomy, the diaphragmatic motion had not changed signifi cantly. The diaphragmatic motion of the operated side was impaired signifi cantly more (p = 0.035) in the supine position than in the sitting position. Conclusion: Our results indicated that magnetic resonance imaging (MRI) was useful for quantifying the impairment of the diaphragmatic motion after lung resection.

Tubes, lines, and catheters in plain chest fi lms: An abc guide for the assessment of normal and pathological fi ndings D.D. Cokkinos, G. Giannakopoulou, E. Daskalaki, M. Avlianos, A. Bouga, A. Kontogiannis, N. Gavalas; Athens/GR (ggiannakopoulou@gmail.com)

Learning Objectives: To illustrate the essentiality of evaluating the position of tubes, lines and catheters in chest X-rays. Background: Tubes, lines and catheters are common fi ndings on everyday radiographs, especially chest studies. It 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, and cardiac pacemakers. Unfortunately, lack of familiarity with these devices leads to misjudgement of proper positioning, and therefore immediate or delayed complications. Procedure Details: We inspected retrospectively chest radiographs from 65 patients (neonates, children, and adults) and concentrated on identifying all tubes, lines and extraneous devices. We reviewed the fi lms with respect to normal positioning and malpositioning. We also looked out for complications associated with inappropriate positioning or malfunctioning devices, such as pneumothorax, air embolism, perforation and bleeding. In addition, we assessed the device's integrity and alignment, receiving valuable information for the patient's general health or lack thereof. Conclusion: Familiarisation with normal and abnormal fi ndings of tubes, lines and catheters is essential and leads to proper management and treatment of the patients.

Molecular targeted anti-cancer therapeutic agents for non-small cell lung cancer: Mode of action, current results, and radiologic fi ndings after treatment using these agents C. . The knowledge about molecular targeted anti-cancer agents and familiarity with the images of the patients treated with these agents will be mandatory for the radiologists to determine the accurate tumor-response to the molecular targeted agents.

The spectrum of diseases causing airway mucoid impaction J. Euathrongchit 1 , N. Learning Objectives: To systemically review the imaging aspects of the spectrum of diseases causing mucoid impaction of the airways. Background: Mucoid impaction, mucus plugs, and bronchial mucocele are similar conditions resulting from accumulation of inspissated secretions such as mucus/ pus/ infl ammatory products within the bronchi, which are usually dilated. Mechanisms resulting in this condition are abnormal mucociliary transport, excessive production of mucus, and collected mucous in bronchi distal to an airway obstruction. Procedure Details: In this exhibit, we follow the above mechanisms to display the variety and spectrum of presentations of mucoid impaction. Conclusion: This educational computer exhibit reviews the spectrum of the radiographic features of mucoid impaction on chest radiographs, CT and MRI and the underlying mechanisms responsible.

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Pleuropulmonary manifestations of asbestos-related disease: Computed tomography (CT) fi ndings Z. Khaleel, C. Viswanathan, R. Lavakumar, N. Kennan, G. Avery; Hull/UK (ziyadlk@hotmail.com)

Learning Objectives: To review and illustrate the imaging spectrum of Asbestosrelated disease of the lungs and the pleura with emphasis on computed tomography (CT) fi ndings. Background: Asbestos fi bres inhalation is known to induce a range of pleural and pulmonary disorders. High levels of asbestos exposure have gradually been prohibited since the 1970s in many countries. Prevalence of this disorder is still rising; however, this is secondary to the long latency period (20 years or longer) between initial exposure and development of the disease. Imaging Findings: Benign pleural disease is the commonest encountered manifestation and includes pleural effusion, pleural plaques, rounded atelactasis and diffuse pleural thickening. Although lung parenchyma is thought to be less sensitive to the effects of the fi bres than the pleurae, asbestosis is a well-recognised sequel to prolonged asbestos inhalation. Malignant manifestations include bonchogenic carcinoma and malignant mesothelioma.

Owing to the accuracy of imaging in asbestos-related disease and the medicolegal implications of the diagnosis, the radiologist plays a pivotal role in the disease management. We aim to present a review of the CT/HRCT fi ndings of this debilitating illness.

Spectrum of radiological appearance of chest ports and catheters: An exhibit for non-interventional radiologists M. Diaz, A. Villanueva, G. Bastarrika, J. Noguera, J. del Pozo, A. Alonso-Burgos;

Learning Objectives: To describe the radiological features (chest X-ray, CT and US) of chest ports and reservoirs (CR) commonly used for chemotherapy administration. To describe the radiological fi ndings of the complications that may occur with these devices. Background: Chest ports play an important role in the management of oncology patients who need frequent blood products, chemotherapy and other intravenous drugs. Chest port related complications may arise during their placement, removal or the meantime and they may be asymptomatic. Many cases of catheter-induced central thrombosis go unrecognized, but the incidence of pulmonary embolism in this group may be as high as 12%. Plain fi lms, ultrasound and CT are useful for the prompt diagnosis of these complications. General and oncology radiologists rather than interventional radiologists play an important role in their detection. Imaging Findings: Normal imaging fi ndings (plain fi lms, US, and CT) of the different ports and reservoirs and some common interpretation pitfalls, such as thrombus formation inside a vein, are described. Radiological fi ndings of reservoir associated complications such as rotation, thrombosis, and infection and catheter related complications such as mural, tip and sleeve thrombosis, displacement, breakage, migration and infection are discussed. Conclusion: Appropriate knowledge of the normal CR appearance and radiological fi ndings of CR related complications is important in order to facilitate a prompt and effective diagnosis. General radiologists are encouraged to consider the CR as an area of interest when interpreting imaging studies. The knowledge of pathologic processes that affect the chest wall and its radiological fi ndings allow us to establish a specifi c diagnosis in a great percentage of the cases. However, when chest wall lesions show a non-specifi c radiological behaviour, imaging techniques provide a strategy in the workup of an accurate diagnosis, and is a useful guide for biopsy and for the surgical approach.

Thoracic manifestations of sickle cell disease in children E.J. Helm, P.S. Babyn, P. Parkin; Toronto, ON/CA (paul.babyn@sickkids.ca) Learning Objectives: To illustrate the spectrum of thoracic pathology seen in sickle cell anemia as demonstrated by plain radiography, CT and MRI Background: Sickle cell disease (SCD) is a hemoglobinopathy characterized by changes in all major organ systems. The lung and heart are major target organs in this disease. Specifi c manifestations of pulmonary disease include the acute chest syndrome and sickle chronic lung disease. Cardiovascular manifestations include pulmonary hypertension, multiple chamber dilatation, myocardial ischemia and infarction. Thoracic disease is frequently associated with other severe manifestations of sickle cell anemia such as neurological disease and bone infarction. Imaging Findings: We will illustrate the common and uncommon manifestations of SCD including acute chest syndrome, chronic lung disease and pulmonary hypertension. In the acute chest syndrome, plain fi lm fi ndings may be subtle or absent. A rapid progression to multifocal consolidation and an ARDS type picture may occur. CT may demonstrate hypoperfusion and ground glass shadowing and better depicts early changes. Plain fi lm fi ndings in chronic sickle lung disease include fi brosis and cor pulmonale. CT changes include interlobular septal thickening, reticular abnormalities, pleural tags and lobar volume loss. Echocardiographic fi ndings of chamber dilatation and pulmonary hypertension have been extensively reported. SPECT imaging can demonstrate further fi ndings of ischemia or infarction. Conclusion: Thoracic disease due to sickle cell anemia has many different manifestations. Although the chest radiograph has traditionally been used for assessment, other imaging modalities frequently add additional important information.

Congenital cystic adenomatoid malformation: Is CT a useful predictor of histological type? N. Griffi n, A. Deveraj, A. Nicholson, S. Padley; London/UK (nyreegriffi n@hotmail.com) Purpose: Congenital cystic adenomatoid malformations (CCAMs) are rare congenital lung lesions recently reclassifi ed into 5 subtypes (0-4). Subtype 1 may undergo malignant transformation. There is also overlap between type-4 CCAMs and type-1 pleuropulmonary blastomas. The aim of this study was to determine if pathological subtypes 1, 2 and 4 show characteristic changes on CT that may aid preoperative diagnosis Methods and Materials: CT studies were reviewed for 14 consecutive patients referred postnatally with the histological diagnosis of CCAM on surgical resection. Results: Median age at the time of resection was 3.2 years (range:1.2-23.4). Five patients were females. Five patients had type-1 histology; 6 were type-2 CCAM; and 3 were type-4 CCAM. No type-0 or type-3 lesions were encountered. CT review indicated the following: Most lesions were in the lower lobes (11). Lesion size and cyst number were variable (from 1 to over 40 cysts), and did not depend on histological type. Type-1 lesions had well-defi ned cysts, with maximum cyst diameter exceeding 4 cm. Type-2 lesions had cystic change in 5 cases, with maximum cyst diameter measuring less than 2 cm. Areas of reduced attenuation were also seen (5). Type-4 lesions showed either microcystic (1) or macrocystic change (2), with mass effect demonstrated in all 3 cases, and contralateral mediastinal shift seen in 2 cases. One patient also had pleural nodules. Imaging Findings: Imaging fi ndings are based on chest radiography and computed tomography. Most frequent fi ndings in pulmonary infections are patchy, bilateral and rapidly progressive condensations associated with severe respiratory failure. In addition, 8 patients had brain lesions secondary to embolic dissemination. Imaging fi ndings are fairly similar to those encountered in disseminated aspergillosis; however, all these patients had a fatal and rapid evolution, because this fungus is resistant to all anti-fungal therapies known. Autopsy demonstrated necrosis and hyphae proliferation inside the thoracic and brain lesions. Conclusion: Scedosporium prolifi cans must be included in the differential diagnosis of rapid lung infi ltrates in deep immunocmpromised patients in some western regions of Europe and Australia.

Non pulmonary primary thoracic malignancies: A radio-pathological correlation A. Donuru 1 , V. Kandula 1 , A. Barbieri 2 , J.J. Entwisle 1 ; 1 Leicester/UK, 2 Northampton/UK Learning Objectives: The purpose of this exhibit is to describe the radiological fi ndings of various non-pulmonary primary thoracic malignancies. All the cases illustrated are pathologically proven. Background: Thoracic cancer comprises many different types of cancer that strike the thorax. Some types are common, such as lung cancer and esophageal cancer. Some are rare. Imaging Findings: The pathologies included are lymphoma (Hodgkin's and Non Hodgkin's), breast cancer, oesophageal cancer, mesothelioma, sarcoma, thymoma, angiosarcoma, leiomyosarcoma, chondrosarcoma, ganglioneuroblastoma, malignant fi brous histiocytoma, rhabdomyosarcoma, haemangioendothelioma, plasmacytoma and neurilemmoma. Conclusion: It is important for the radiologists to have an awareness of the imaging fi ndings of the above mentioned thoracic malignancies. When the diagnosis is not clear on a chest radiograph or on computed tomography it is strongly recommended that a biopsy is performed for pathologic confi rmation.

Normal variants-congenital thoracic anomalies in adults year old (37-74 years old) were included. 28 cases were analyzed. The ratio of primary and metastases was 17:6. Mean tumor dimension is 37.9 mm. Pathology were squamous cell ca (8), adenocarcinma (9), metastases (hepatocelluar ca (2), renal cell carcinoma (2), colon cancer (1), soft tissue sarcoma (1)). CT guided cryoablation was performed under the local anesthesia by guidance of CT. Mean ablation is 2.4 per patient. Sequential CT was acquired on 1, 3, 6 mo. CT fi ndings were analyzed (maximal dimension, mean attenuation). We analyzed sequential changes of volume and mean ROI. Nine of them were correlated with PET-CT for evaluation of viable component.

Major symptoms (cough, dyspnea, and hemoptysis) were assessed and showed improvement in symptoms. Mean admission was less than 1 week. Complications were pneumothorax (6), hemothorax (1), hemoptysis (10), pleural effusion (6). Patients were followed for a mean period of 11 months (4-23 months). In metastases, perilesional necrosis was more prominent in immediate CT (within 1 week). Six cases were increased dimension. Necrosis was shown in fi ve cases. Five have increased CT attenuation than initial CT. Conclusion: Cyoablation plays an important role in palliation of advanced cancer, post operative recurrence, or metastases. Our study suggests that adequate palliation may be achieved by cryoablation applied to advanced cases. It was recently reported that the WHO classifi cation refl ects the clinical features of and is one of the prognostic factors for thymic epithelial tumors. FDG-PET exhibits accumulation, also refl ecting the malignancy of the tumor; it is useful in differential diagnosis according to the WHO classifi cation. It is believed that the procedure plays a key role in the diagnosis of thymic epithelial tumors. were reviewed by two radiologists in consensus. 1.2 mm thin-section CT fi ndings were evaluated about the size, density, shape, border margin, marginal irregularity, spiculation and lobulation. The density was measured by setting of ROI in size of a maximum short-axis diameter of the lesion. The uptake of FDG was represented as maximum standardized uptake value (SUV). These CT fi ndings and SUV were statistically compared. Results: Tumor size and density were signifi cantly correlated with SUV (p < 0.001).

Mean SUV of lesions with lobulation and without lobulation were 8.4 and 5.9, respectively and SUV of lesions with lobulation was signifi cantly higher than that without lobulation (p < 0.01). Mean SUVmax of lesions with spiculation and without spiculation were 4.2 and 7.5, respectively and SUV of lesions with spiculation was signifi cantly lower than that without spiculation (p < 0.05). The other fi ndings were not signifi cantly correlated with SUV. Conclusion: A low FDG uptake of lung lesions in small size, with low CT density or spiculation are not reliable fi ndings to deny lung cancer. In contrast, a low FDG uptake of the lesion with lobulation-like fi nding or high CT density may suggest the lesion benign.

Value Seventy-nine patients (10 F, 69M; mean age 62 years) referred for suspicious of lung cancer based on chest radiography fi ndings were studied. Patients with previous diagnostic CT were excluded. Image acquisition was performed with a combined PET-CT in-line system from head to mid-thigh, 50 minutes after intravenous administration of 370 MBq 18 F-FDG, and with administration of iodinated intravenous contrast, and water as oral contrast. Biopsy and/or fi ne needle aspiration were obtained in all cases and served as standard of reference. Results: PET-CT correctly classifi ed 71 patients as neoplastic. Twenty-seven corresponded to adenocarcinoma, 14 to squamous-cell carcinoma, 25 to large-cell carcinoma and 5 to small-cell carcinoma. The remaining 8 patients were falsepositives corresponding to infl ammatory-infectious processes (3 abscesses, 3 tuberculosis and 2 neumonia) that simulate lung cancer. The sensibility and the predictive positive value were 100 and 89.87%, respectively. In all the patients, PET-CT avoided the performance of other imaging modalities such as contrastenhanced body CT and bone scintigraphy. Conclusion: Our initial results indicate that 18 FDG PET-CT may be useful as fi rstline imaging modality in patients with suspected lung cancer and help in avoiding other diagnostic procedures.

The comparison of PET-CT and chest CT for staging in lung cancer D. Kim, J. Yang, J. Byun, Y. Kim; Gwangju/KR (dhk1107@hanmail.net)

Purpose: The goals of this study are to estimate the effi cacy of PET-CT and chest CT, alone and combined, in tumor staging and to exhibit various false (positive or negative) fi ndings mimicking true fi ndings.

This study enrolled 33 patients with lung cancer who had undertaken PET-CT and chest CT. The age range of the consecutive patients is 35-81 years (mean age: 60.8 years). Both studies were done within 27.1days. Two independent readings were obtained from each test, and discrepancies were solved by consensus. Bronchoscopic biopsy or percutaneous transthoracic lung biopsy was performed by one radiologist and one physician. All cases were confi rmed pathologically. The correlation of tumor stages by PET-CT or chest CT, and both studies combined were evaluated. Also, various false-positive or false-negative fi ndings of PET-CT were demonstrated, thereby causing diffi culties in accurate staging. Results: Agreement in PET-CT for staging of lung cancer is 21.2% (7 cases). Overestimated stage for lung cancer by PET-CT was seen in 12 cases (36.3%) and 8 cases (24.2 %) were interpreted to be in an underestimated stage. In 6 cases (18.2%), malignancy was not proved. Diseases causing false-positive fi ndings were infl ammatory granuloma, reactive lymphadenopathy, and infl ammations such as pneumonitis, pneumonia, lymphoma. Small cancer or small malignant lymph nodes showed false-negative PET fi ndings. Conclusion: PET-CT and chest CT showed similar results in staging of lung cancer. Two studies represented high conditional dependency. Also, for the proper interpretation and accurate diagnosis of lung cancer by PET-CT, the various false fi ndings of PET-CT should be understood.

Dual Results: Pathology was 37 of squamous cell ca and 31 of adenocarcinoma. The stages were 6 IA, 11 IB, 9 IIA, 12 IIB, 14 IIIA, 11 IIIB, and 5 IV. There is a signifi cant correlation between SUV of primary lesion and presence of nodal or distant metastases and RI value were higher than squamous cell carcinoma than adenocarcinoma. Mean SUV of each group is 16.1:5.6 (squamous:adenocarcinoma). The RI ratio is 20.5:12.5 (squamous:adenocarcinoma). The SUV of the lymph nodes were similar pattern RI to the primary mass. Conclusion: PET SUV, independent of size, is a marker of biologic aggression that can predict the specifi c histopathology for non small cell cancer. Higher level SUV of primary mass favors squamous cell carcinoma than adenocarcinoma.

386 B D E F A G Chest Vascular

Perforating branches of the internal thoracic artery: An anatomical study using MDCT angiography K. Nakatani, H. Maeda, N. Hamada, T. Yamanishi, K. Miyatake, A. Nishioka, Y. Ogawa; Nankoku/JP (jm-nakakimi@kochi-u.ac.jp) Purpose: Breast reconstruction is a crucial technique for patients after breastconserving surgery. Breast reconstruction with consideration of the breast blood supply offers the potential of avoiding complications such as breast scleroses and adiponecrosis. The present study aimed to determine the locations, courses and distributions of perforating branches of the internal thoracic artery (ITA), the major artery infl ow to breast tissue from the inner side, using multi-detector row-computed tomography (MDCT) angiography. Methods and Materials: Subjects in this prospective study comprised 39 women with suspected breast cancer who underwent MDCT angiography between April 2004 and December 2005. Perforating branches of the ITA were identifi ed on a dedicated workstation using transverse sections and 3-dimensional images. Distributions of the identifi ed perforating branches were investigated. Depth of perforating branches was measured and analyzed using simple regression analysis.

Results: A total of 48 perforating branches were found, with 27 branches (56.3%) originating in the second intercostal space and 7 branches (14.6%) originating in the third intercostal space. Most branches from the second intercostal space turned horizontally after running cranially. Most branches from the third intercostal space ran horizontally. A strong correlation was identifi ed between distance from skin to branches and adipose thickness at the shallowest and deepest points (P < 0.001).

We succeeded in detailing the course, length and distribution of ITA perforating branches using MDCT angiography. These results for distribution and depth of ITA-perforating branches will prove helpful in performing immediate breast reconstruction following breast-conserving surgery.

And Learning Objectives: To review the embryologic features of the aortic arch specially focussed on right-sided aortic arch development. To describe the most relevant fi ndings of the right arch, great vessels and associated anomalies to aid potential surgical procedure. Background: The right-sided aortic arch is an uncommon congenital defect of the aorta. It is present in 0.05% to 0.1% in radiological series. Deletion in chromosome 22q11 is associated in 24% of isolated anomalies of laterality of branching of the aortic arch. Using Edward´ s hypothesis, three types are described: type 1, with mirror-image branching of the major arteries; type 2, with an aberrant subclavian artery; and type 3, with isolation of the subclavian artery. Congenital heart anomalies are usually present in types 1 and 3. The initial fi ndings by the chest-x ray and barium swallow suggest the anomaly. However, CTA or MRA should be performed to confi rm the defi nitive diagnosis. Background: PH is a complex life-threatening condition with numerous aetiologies. Symptoms such as breathlessness on exertion, fatigue and chest pain are non-specifi c and are often attributed to more common disorders such as asthma delaying diagnosis. Treatment has a profound impact on outcome. A specifi c diagnosis is important as therapeutic options range from surgical intervention to targeted medical therapy. Since biopsy may be hazardous in this patient population, imaging plays a central role in establishing a diagnosis and guiding therapy. Imaging Findings: Imaging features in PH can be divided into those that are common to all aetiologies and those that are disease specifi c. An understanding of the pathophysiology and classifi cation of the PH aids diagnosis. We will present imaging data from patients presenting to a national centre for PH and pulmonary thromboendarterectomy with pathologic correlation in specifi c cases.

The radiologist plays a central role in the diagnosis of PH. It is important to be aware of the general and more specifi c imaging features in the spectrum of diseases associated with PH as early diagnosis and targeted therapies can improve the outcome.

The importance of looking at the heart when interpreting standard thoracic CT E. Castaner 1 , Y. Pallardó 2 , X. Gallardo 1 , M. Prieto del Rey 1 , S. Perez Aguilera 1 , J. Mata 1 ; 1 Sabadell/ES, 2 Alzira/ES (ecastaner@cspt.es)

Learning Objectives: To familiarize viewers with the normal anatomic structures of the heart and pericardium to avoid mistaking them for pathologic processes. To explain the signifi cance of some incidental fi ndings. To emphasize the importance of looking at the heart when interpreting a thoracic CT study, especially in some particular clinical settings. Background: Important information concerning the heart can be obtained on both un-enhanced and contrast-enhanced CT of the thorax. Cardiac disorders can often complicate or coexist with extracardiac thoracic disease, and may often remain unsuspected or underevaluated. Correct analysis of images of the heart and surrounding structures depends on a thorough understanding of cardiac anatomy and on the ability to recognize the normal and abnormal appearances of the heart commonly observed on CT. Imaging Findings: We show anatomic structures that can be misinterpreted (crista terminalis, eustachian valve, fossa ovalis, coronary sinus, valves, pericardial recesses, paracardiac structures); some incidental fi ndings and their clinical value (calcifi cations, dilatations, fat deposition, increased or decreased myocardial density) classifi ed considering the structure involved: valves, chambers, pericardium. We comment on some clinical situations with possible cardiac repercussion: pulmonary hypertension, pulmonary embolism, neoplasms, and chest wall disorders. Conclusion: Knowledge of cardiac anatomy is essential to avoid mistaking normal anatomic structures for pathologic processes. It is important to know the clinical relevance of some incidental fi ndings and which of them will require further examinations. Radiologists need to know conditions that may have an important effect on cardiac structure and function.

MSCT and MRI of the pulmonary veins: Anatomy, anatomic variations and anomalous pulmonary venous drainage A. Alonso -Burgos, L. Diaz, J. Noguera, E. De Luis, A. Villanueva, J. Larrache, G. Bastarrika; Pamplona/ES (alonso@unav.es)

Learning Objectives: To describe MSCT and MRI features of the normal anatomy, anatomical variations, and anomalous returns of the pulmonary venous system. To emphasize the capability of MSCT and MRI to non-invasively map pulmonary venous and left atrial anatomy before the percutaneous ablation. Background: Assessment of pulmonary venous and left atrial anatomy has become a hot topic among cardiac electrophysiologists, as radiofrequency catheter ablation is being increasingly used for atrial fi brillation. Both MSCT and MRI provide detailed and accurate anatomic information about the pulmonary veins and additional anomalies that are commonly associated with the development of atrial fi brillation. Axial images and especially volume-rendered reconstructions allow to precisely determine the anatomy, anatomic variations, anomalous returns, and total number of pulmonary veins, thereby facilitating the interventional procedure. Imaging Findings: In this exhibit, normal pulmonary venous MSCT and MRI anatomy and anatomical variations will be discussed. Anomalous pulmonary venous returns as well as associated anomalies will also be illustrated. The role of MSCT and MRI to non-invasively depict pulmonary venous and left atrial anatomy before the ablation will be emphasized. Conclusion: MSCT and MRI allow a rapid non-invasive assessment of normal pulmonary venous anatomy and associated anomalies. Preprocedural exact delineation of these structures might facilitate the percutaneous intervention in patients with atrial fi brillation. Background: Central venous catheters and other devices are routinely used in the hospitable practice; for this reason, the correct knowledge of the thoracic venous anatomy is basic. MDCT angiography is the best non-invasive method to describe it, and it offers us the possibility to diagnose thoracic venous disorders that could be important for placing catheters and, consequently, to avoid iatrogenic complications. Procedure Details: We employed 16 slice MDCT for study of all chest on a single section helical. A table feed of 5 mm per rotation, and a reconstruction increment of 1.25 mm are used. 100 mL of non-ionic contrast material is injected at 4 mL/second, immediately followed by injection of 30-40 mL of saline solution at the same injection rate. The images were acquires at 20 seconds. At the workstation, we performed multiplanar reconstructions. Conclusion: MDCT angiography is the most reliable method in the non-invasive diagnosis of thoracic venous disorders.

Comparative analysis of methods for determination of blood fl ow parameters in non-small-cell lung cancer Results: rBV PA from ED and LD were 10.1±1.0 ml/100 ml tissue and 38±5 ml/100 ml tissue, respectively. rBV IDT was 10.0±2.0 ml/100 ml. PS from ED and LD were 23.5±2.0 ml/100 ml/min and 0.24±0.01 ml/100 ml/min. The rBV PA and rBV IDT values showed signifi cant correlation (r=0.58, p < 0.05). Relevant correlation between rBV PA as well as PS from ED and LD were not found. Conclusion: Our results support the statement that rBV and PS measurements are time-dependent and probably may not be calculated using late data sets. Further research is needed for the determination of the appropriate time of data acquisition. The optimization of the DCE-CT study protocol could improve the qualitative and quantitative assessment of functional tumor data. These parameters could serve as prognostic factors or may be used for follow-up studies.

Shortest guide to anatomy of pulmonary arteries evaluated in multislice computed tomography angiography G.J. Staskiewicz, E. 

Assessment of a pulmonary angiography 16-row MDCT protocol using 100 kVp in comparison to a 120 kVp protocol: A prospective randomized trial P. Mohr, S.A. Peters, S.P. Lemburg, V. Nicolas, C.M. Heyer; Bochum/ DE (christoph.heyer@rub.de) Purpose: To implement a pulmonary angiography MDCT protocol using 100 kVp, and to compare vessel enhancement, SNR, CNR, radiation exposure, and subjective image quality to a protocol using 120 kVp. Methods and Materials: Sixty patients were referred for evaluation of suspected pulmonary embolism by CT angiography on a 16-row scanner. Patients were randomly assigned to a CT protocol using 100 or 120 kVp, respectively. All other scan parameters including tube current, collimation, and gantry rotation time were kept constant. Contrast media was injected using bolus tracking. Based on density measurements, pulmonary vessel opacifi cation and image noise were quantifi ed and SNR / CNR were calculated. Subjective vessel contrast was assessed by two radiologists in consensus. Effective dose was calculated based on DLP/CTDI values. Results of both protocols were compared using chi-square-test and student's t-test.

The 100 kVp protocol showed a non-signifi cant higher mean vessel density than the 120 kVp protocol (387±130 HU to 318±113 HU; p=0.56) and a non-significant higher image noise (17±6 HU to 14±6 HU; p=0.84), resulting in almost identical SNR (25±12 to 27±15; p=0.37) and CNR (22±11 to 23±13; p=0.51). Furthermore, subjective image quality showed no signifi cant differences between the two protocols. Mean effective dose of the 100 kVp protocol was signifi cantly lower compared to the 120 kVp protocol (1.37±0.39 mSv to 2.44±0.98 mSv; p < 0.001). Conclusion: Reduction of tube kilovoltage from 120 to 100 kVp resulted in significant reduction of effective dose in pulmonary 16-row MDCT angiography without signifi cant loss of objective and subjective image quality.

The post-processing of multi-slice CT in the interpretation of chest traumas W. Yang 1 , C. Beigelman-Aubry 2 , A. Brun 2 , P.A. Grenier 2 ; 1 Shanghai/CN, 2 Paris/FR Learning Objectives: To outline the indication and advantage of multislice CT post-processing in the interpretation of chest traumas. To demonstrate several potential pitfalls in the interpretation and the method of avoiding these pitfalls with the post-processing technique. Background: Chest traumas are responsible for approximately 25% of traumarelated deaths. They are associated with high morbidity and mortality rates. CT, especially with the post-processing technique, including MPVR, MIP, mIP, volume rendering, provides fast, sensitive, and accurate evaluation of vascular, pulmonary, airway, skeletal and diaphragmatic injuries. Imaging Findings: 2D reformations provide a panoramic view of all the chest structures, allowing the detection of minor fractures. Curved reformations provide information of excellent value in case of spine injuries. MIP-MPVR may be used in the evaluation of vessel injuries as and costal cartilage injuries. Mini-IP is useful in the detection of all lucent lesions, including pneumothorax. pneumomediastinum, tracheobronchial ruptures or pulmonary hernia. Volume rendering is particularly helpful in case of thoracic cage trauma.

The post-processing techniques used in the diagnosis of chest trauma are highly informative. A rigorous protocol with optimized use of reconstructions is required. 

Computer-aided detection (CAD) in lung cancer screening at chest MDCT: ROC analysis of CAD vs. radiologist performance F. Fraioli, L. Bertoletti, M. Mennini, R. Lezoche, C. Catalano, R. Passariello; Rome/IT (francesco.fraioli@uniroma1.it)

Purpose: Our aim was to compare the performance of radiologists against a CAD algorithm for pulmonary nodule detection on MDCT.

Methods and Materials: Three radiologists independently analysed 200 scans and assigned each nodule a confi dence score (1-3). CAD was applied to all scans, successive readers re-evaluated all fi ndings of the CAD, assigning, in consensus, a confi dence score (1-3). The reference standard was established by other two experienced chest radiologists. Results were used to generate an FROC analysis.

The reference standard showed 124 nodules. Sensitivity for readers I-II-III was: 48, 61, and 36%. A double and triple reading resulted in an increase in sensitivity up to 72%. With CAD, sensitivity was increased to 91, 94, and 92% for readers I, II, and III. The area under the FROC curve (Az) was 0.53, 0.69, 0.42, and 0.80 for readers I, II, III, and the CAD. Differences between all readers and the CAD were signifi cant (P < 0.05). For nodules > 6 mm Az was 0.72, 0.88, 0.64 and 0.88 for readers I, II, III, and the CAD. P was signifi cant between reader I and the CAD and between reader III and the CAD, it was not signifi cant (P=0.9) between reader II and the CAD. For nodules < 6 mm, Az was 0.18, 0.19, and 0.17 for readers I-III and 0.63 for the CAD. Differences between all readers and the CAD were signifi cant (P < 0.05). Conclusion: CAD can aid in daily radiological routine detecting a conspicuous number of nodules unseen by radiologists. 

Pathological diagnosis was achived by surgery in 25 patients and with a follow-up in 5. Sensitivity, specifi city and accuracy of malignant nodules was calculated by considering single slice Vs total volume wash in and wash out of c.m. Thirty PN with 18 benign and 12 malignant were included in our analysis. Diagnostic criteria of malignancy included those nodules with a wash in of 25 HU and a wash out less than 30 HU. Results: An almost perfect agreement was obtained between the two measurements in the diagnosis of benign nodules while a disagreement occurred in 2 PN histological malignant. In those nodules, a wash in enhancement greater than 25 HU was shown for both measurements but with a wash out respectively greater and smaller than 30 HU when single axial or volumetric assessment were performed. Conclusion: Volumetric assessment of the wash in and wash out curves appears more accurate and reproducible allowing a better evaluation of densitometric curves and reducing limits of single slice evaluation. Moreover, dedicated software may provide a semi automatric analysis with a reduction in the evaluation time and more comparable results.

Impact of the digitalization of a radiology department in the detection of lung cancer in the emergency department I. Herrera, M. García Hidalgo, C. Varela, C. Ruiz, C. Romero, J. Pinto;

Purpose: To evaluate the impact of the digitalization of a radiology department in the detection of lung cancer in the emergency department (ED).

We retrospectively reviewed and compared the number of lung cancer cases detected in the ED by using conventional (year 2003) and digital (year 2005) chest radiography. Our radiology department became completely digital in 2004. This new situation brought the opportunity of having the images available at any time and made possible the later review of the images acquired at the ED by an expert radiologist. We analyzed the role of an expert radiologist together with the availability of previous images. Results: In 2003, 112 lung cancers were detected and histologically confi rmed at our institution. Thirty-eight (33.9%) were detected at the ED. Twenty (52.6%) of them were detected by a radiologist and 24 (63.2%) patients had previous radiographs at our institution although no image was available. In 2005, 89 lung cancers were detected and histologically confi rmed. Forty-fi ve (50.6%) of these cancers were detected at the ED. A radiologist reported as abnormal 73.3% of those cases. Thirty-three (73.3%) were previously imaged at our institution. Twenty-two (66.6%) were reported by a radiologist and 14 (36.9%) of them had the image available in digital format.

The digitization of the ED increased the rate of lung cancers detected at this department. The number of cases interpreted by an expert radiologist, the availability of previous images and reports has also increased due to the digitization of the radiology department.

Towards international standardization of medical images distribution workfl ow through portable media E. Avraham; Plano, TX/US (eli@kodak.com)

Learning Objectives: To demonstrate limitations in distributing medical images through portable CD media. To present a reliable workfl ow for importing and reconciling medical images using the IHE profi les "Portable Data for Imaging" (PDI) and "Import Reconciliation Workfl ow" (IRWF). To demonstrate use cases for distributing and reconciling medical images through portable CD media. To enhance the portable media distribution workfl ow for non-imaging health IT documents. Background: The healthcare information distribution on CD media is rapidly increasing and reduces cost and network dependency. For example, operating rooms, dental and referral physicians increase their use of sharing images through CD media. The lack of standardization on the health CD data organization and data types reduces the client's capability to access the data and display it correctly. This educational exhibit proposes a standard solution, based on IHE profi les: PDI and IRWF, to provide a reliable distribution of imaging information on interchange media for import, display and print. Procedure Details: This educational exhibit includes but is not limited to (1) demonstrating current limitations on distributing medical images through portable CD media, (2) presenting a reliable workfl ow for importing and reconciling medical images using IHE profi les PDI and IRWF, (3) demonstrating the use cases for sharing medical images through portable media, (4) Extend the portable CD media distribution for other non-imaging, health IT EHR information.

The standardization of the portable media distribution is improving the medical image distribution and sharing, which is a key in improving the patient health practices and reducing healthcare operational cost.

Internet guide for radiologists D. Volpe, N. Volpe, N. Masiello, A. Saponaro, A. Carriero; Novara/IT (dvolpe@sirm.org)

Learning Objectives: To describe the principal possibilities offered by the Web and provide basic indications that will encourage inexpert people to embark on a personal exploration adapted to their needs and abilities. Background: Information interesting to physicians accounts for a large part of the multimedia world of the Internet in both quantitative and qualitative terms. Hundreds of the many sites containing medical information are dedicated to imaging diagnostics, their number is constantly growing, and their nature is constantly changing. This means that the information is dispersed and often half hidden in a vast range of site categories or local resources, thus making it diffi cult to evaluate its quality and reliability in an objective manner. Procedure Details: Among the vast range of resources of radiological interest on the Internet, we propose a classifi cation of the sites that facilitate navigation to the greatest extent and directly supply the type of information being sought. The sites have been grouped into seven ideal folders: catalogue sites, institutional sites, specialised sites, radiological image databases, on-line journals, sites offering teaching material, and discussion forums. Conclusion: Our aim is to propose a digital guide of free Internet resources for radiologists.

E-anatomy.org: A free interactive atlas of whole body sectional anatomy A. Micheau, D. Hoa; Montpellier/FR (denis.hoa@campusmedica.org) Learning Objectives: To provide an e-learning website about sectional anatomy of the human body, with interactive self-study and assessment tools, based on more than 1500 MR and CT slices. Background: On one hand, information and communication technologies (ICT) act as a catalyst for innovation in learning, giving access to relevant, interactive, high-quality content. On the other hand, improvements in CT (e.g. multisection CT) and MR imaging (improved spatial resolution) deliver highly detailed images of internal anatomy. Thus, interactive computer-based content and Flash animations could be used to create new ways to teach sectional anatomy. Procedure Details: We chose normal CT and MR exams. More than 1500 slices were selected in order to cover the entire sectional anatomy of the human body. Images were labeled using Terminologia Anatomica. We built a user-friendly interface, which allows to cine through multi-slice image series combined with textual information, 3D models and anatomy drawings. Learning assessment is provided 390 B D E F A G by self-tests. All these teaching modules are available on the Internet. Conclusion: e-learning and interactive Flash animation combined with the latest multi-slice CT and MR imaging technologies offer new ways to teach radiological whole body human anatomy. We provide a useful, free, interactive tool for the radiologist's everyday use; available online at http://www.e-anatomy.org. Massachusetts, USA) was used for writing codes of both mathematical equations and the graphical user interface. Technical aspect presented by this system can provide the 3 parts: (1) image processing and analysis using full-fi eld digital mammography, (2) quality control (QC) tools improved the effi ciency of periodic tests, and (3) GUI-based checker for clinical breast examination and mammography fi ndings. Granulometry was implemented in this program with basic imaging fi lter (smoothing, edge-enhancement and adaptive wiener fi lter). Granulometry determines the size distribution of the region of interest (ROI) in a mammogram.

The software we developed for supporting breast cancer screening had a benefi cial effect to improve the effi ciency of QC and the diagnostic work of mammography.

Virtual colonoscopy: CAR versus non-CAR A. Koshman; Moscow/RU (falko77777@rambler.ru)

Purpose: To compare the results of 3D endoluminal analysis using computer assisted reading (CAR) with 3D endoluminal analysis non-CAR by experts for colorectal polyps detection. Methods and Materials: Twenty-eight patients (19 males, 9 females, age range 45-68 years) underwent virtual colonoscopy procedure. All of them had undergone optical colonoscopy which revealed 52 polyps and was used as a reference standard. Two radiologists read the datasets from virtual colonoscopy: one after the procedure, non-CAR; the other radiologist read the data sets using CAR. Sensitivities were calculated. All reading times and number of false-positive results were documented. Results: Sensitivities for clinically signifi cant polyps of 5-9 mm and 10 mm or larger in diameter were: 64% and 75%, respectively for 3D non-CAR and 77% and 88% for 3D CAR (p=0.05). False positive rates (mean) were 4.3 and 1.2 for 3D non-CAR and 3D CAR, respectively (p=0.05). The average reading time for 3D non-CAR was 26.2 minutes (SD±3.8) and 18.3 minutes (SD±3.8) for 3D CAR (p=0.001). Conclusion: Using 3D CAR system provides higher sensitivity, lower false-positive rate and less time per case than 3D non-CAR.

A novel wall thickness-mapped approach of clinical virtual bronchoscopy S. Park, J. Kim, J. Goo, K. Kim, H. Lee, S. Lee; Seoul/KR (lunao78@snu.ac.kr) Learning Objectives: To understand an algorithm of automated assessment of airway wall thickness in chest CT images. To experience the wall thickness-mapped virtual bronchoscopy that visualizes color-mapped wall thickness at each part of airway. To appreciate effi ciency of PC-based application for the virtual bronchoscopy through developed-software. Background: Measurements of bronchial tree airway geometry can be used to evaluate and track the progression of disease affecting the airways, such as asthma, COPD and cystic fi brosis, and to assess the effi cacy of new therapeutic approaches. This exhibit demonstrates a new method for wall thickness-mapped virtual bronchoscopy through measurement of airway wall thickness with a proposed algorithm. Procedure Details: We present an enhanced virtual bronchoscopy that allows assessment of wall thickness during the virtual fl y-through using the steps below.

Firstly, the airway trees are segmented, and then airway center-lines and bifurcation points at each generation are acquired with morphological analysis. Then, we can calculate every wall thickness of each generation of the volumetric airway tree by using a proposed method based on vector analysis with perpendicular plane to airway. Finally, our own software visualizes color-mapped virtual bronchoscopy that refl ects airway wall thickness, fl ying through the inner path of airway. Conclusion: Using CT scans of human cases, we present results showing that this new approach is convenient, accurate, automatic and well-visual in estimating airway wall thickness. Our proposed method can provide pre-operative planning of the intervention for lung surgery with enhanced functional virtual bronchoscopy as a complementary tool for clinical diagnosis and several airway diseases.

A statistical model for the geometric correspondence between differentview breast X-rays taken isochronically from a single breast J. Teubl 1 , H. Bischof 1 , M. Blumenthal 2 ; 1 Graz/AT, 2 Munich/ DE (teubl@icg.tugraz.at) Purpose: We investigated the reduction of false-positive detections of a mammographic CAD system using a new statistical correspondence model.

There is no accurate physical model available to solve the geometric correspondence problem between two different views of the breast; therefore, we propose a new statistical model derived from the cases of a large database. Instead of a direct point-to-point correspondence, we infer the correspondence probability using a probability-estimation technique. The crucial point is the normalisation of point correspondences. In our method, one of the breasts is arbitrarily chosen as the norm breast. The lesions from all other breasts are normalised to this norm breast. This approach provides us with a suffi cient number of point correspondences in one breast to compute a statistical model.

In the fi rst experiment comprising 993 breasts from the DDSM, we compared our statistical model with the recently proposed stripe model. We showed that the statistical model performed better (i.e. using 29% of the breast area as search space, we fi nd 90% of the lesions using our new method compared to 82% when using the stripe model). In the second experiment comprising a smaller set of 70 breasts, we showed that the geometrical correspondence was useful to reduce the number of false-positive detections. Conclusion: If the geometric correspondence information is used, a mammographic CAD system can achieve a higher accuracy. The method introduced in this paper outperforms the recently proposed geometric correspondence models.

Using DICOM header to improve interventional radiology practice: Purpose: To present the usefulness of the information contained in the DICOM header of archived images for patient dosimetry and automatically audit the interventional procedures, and to introduce the consensus of the European SENTINEL consortium in this topic. Methods and Materials: Information on dose, radiographic techniques, beam geometry, C-arm angulations, fi ltration, fi eld of view, collimation, acquisition protocols, post-processing, number of frames that are included in the DICOM header were analysed using CD-ROMs from different interventional X-ray systems installed in several European hospitals. The usefulness of the different parameters to audit the clinical procedures is discussed. Results: When looking at the DICOM header, it is evident that a signifi cant amount of information for dosimetric purposes is contained in private tags. Their format and meaning is unfortunately not easily available and even not well defi ned in the DICOM conformance statement. The dose reports produced by most of the interventional X-ray systems are useful documents, which could help in the audit of patient doses and procedures allowing rough skin dose maps to be calculated retrospectively.

The consensus document issued by the SENTINEL group states that dosimetric, technical and geometric parameters allowing the automatic audit of patient dose and radiological procedures should be contained in public fi elds of the DICOM headers. The work in progress started by IEC to standardize the structure of the dose reports will improve the present situation. Development of software facilitating the extraction of DICOM header information for patient dosimetry and quality control on line should be promoted.

Analysis of nine years of experience with "A walk through radiology" F. Sendra, M.J. Ruiz-Gómez, O. Torales, M. Martínez-Morillo; Malaga/ES (sendra@uma.es)

Learning Objectives: To present a multimedia project focused on training medical students in the visual perception of radiological images and to review the experience in our institution since 1998. Background: E-learning radiology resources are used to be focused on residents or specialists training, our project is addressed to medical students or general practitioners. It does not pretend to be an exhaustive lesson about radiology, but a practical tool to train the user's visual perception. Procedure Details: The application is a PowerPoint based case collection of different image modalities, organized in normal and pathological series. After seeing each case, the user must go to the response screen where several commentaries and marks are shown with animated transitions. Since 1998, this project has taken a part of the practical activities for last course of the medical students in our institution. Questionnaires about performance with computers, evaluation of the application and open suggestions have been collected during this time. Two CD-ROM editions have been published in 2000 and 2002 and the next one will appear at the end of 2006. The purpose of these editions is to distribute to the students and professors at low cost. This project has also been adapted to html to be integrated as a web-based-training resource and version 3.1 is translated into fl ash presentations. Conclusion: This exhibit presents the evolution of this project and the actual 3.1 version, which is presented into six languages Spanish, English, French, German, Italian, and Portuguese, trying to spread "A Walk through Radiology" within European Countries.

Web-navigation guidelines dedicated for radiologists A.N. Chalazonitis 1 , G. Tsimitselis 2 , J. Tzovara 1 , V. Nikolaou 1 , A. Kontogiannis 1 , N. Ptohis 1 ; 1 Athens/GR, 2 Larissa/GR (red-rad@ath.forthnet.gr)

Learning Objectives: 1. To demonstrate simple and advanced Web searching strategies. 2. To provide a list of reference and targeted engines for radiologydedicated search. 3. To identify useful Web resources for radiologists. Background: It is well known that the Web or Internet is a rich illimitable electronic source of information. However, navigation in this unbounded space requires a quiver of valuable tools named "search engines". Three main types of search tools exist: search engines, metasearch engines and subject directories/guides. Any radiological search depends on the strategy used. Procedure Details: In this exhibit, simple and advanced Web searching strategies will be shown. Methods on how to limit or increase results will also be presented combined with various examples. The technique of automated content-based image retrieval, needed to search into image databases, will be also discussed. A complimentary list of references with radiological resources, online databases and targeted engines for the most thorough search will be also provided for the participant. Conclusion: Even though there are several ways to search the Web, a strategy map of radiology-focused navigation should be always available so that any radiologist can get the most information on the least number of Web pages. Its underlying architecture is based on a highly-scalable community framework that is ideally suited to support teaching, research, and administration ROLS allows users and administrators to defi ne different kinds of communities, where each community can be equipped with different tools and resources for shared work, dialogue, and investigation. ROLS "out-of-the-box" consists of a robust portal system, a comprehensive suite of collaborative applications, and an enterprise infrastructure layer based on open standards.

The MUOLS system and its architecture are based on four foundational ideas. 1. Learning is inherently social and takes place most successfully in the context of communities. 2. There is no "right" pedagogical model for learning. 3. The source of innovation is the user, not the manufacturer. 4. Successful online communities (learning communities even more so) must provide extraordinary amount of feedback to participants and administrators.

First Background: Nine patients affected by: 1 atypical pancreatic pseudocyst, 5 endovascularly repaired abdominal aorta aneurysms, 3 foreign bodies retained in soft tissues were submitted to multidetector CT and to US-CEUS examination. Two imaging modalites were coupled, then correlated US probe position to the volume acquired by CT, using an electromagnetic tracker. In pancreatic pseudocyst and in endovascular grafts, CEUS was performed as well. Imaging Findings: CEUS-CT fusion imaging correctly defi ned a small lesion attached to cystic wall as "not solid". CEUS-CT fusion imaging provided functional and morphologic information about aortic endoprostheses. US-CT fusion imaging rapidly identifi es the US position of foreign body in small parts, guiding surgical resection. Conclusion: US-CT fusion imaging offers advantages in terms of cost-effectiveness, time and diagnostic accuracy in different fi elds of application.

A web-based, user tailored and free of charge annotation and image editing program for interactive presentations and teaching fi les R. Talanow 1 , M. Grunewald 2 ; 1 Cleveland, OH/US, 2 Erlangen/DE (roland@talanow.info)

Learning Objectives: To develop an image annotation and presentation program available anytime and anywhere, for creating interactive annotations for teaching fi les and presentations in realtime, free of charge, user tailored, easy to use, with no programming skills and no additional program fi le download necessary. Background: At this time there is no image annotation and presentation program available which creates interactive annotations in realtime, is free of charge, accessible from every computer worldwide and is user tailored. Procedure Details: We developed the multilingual online program Annotate, which allows to create interactive image annotations and presentations. It is available over the internet and accessible worldwide from every computer with internet connection. The author does not need to have programming experience. The image edition as well as the linking and the source code are created automatically by the program. The created website is immediately available worldwide over the internet. The author can change the annotations and presentations at any time and the changes will be done in realtime. There is no need for a fi le transfer after each change. The program can be tailored for the individual user's needs. Conclusion: Annotate (www.annotate.org) is an image annotation and presentation program which is available anytime and anywhere, for creating and changing interactive teaching fi les and presentations in realtime. It is user tailored, easy to use and free of charge. There are no programming skills and no additional program fi le downloads necessary. The user's learning experience may be enhanced by offering multiple modes of presentation.

Interactive volume rendering 3D images for anatomy learning on lowend computers Ö. Smedby 1 , S. Wirell 1 , J. Kvist 1 , C. Silén 1 , G. , volume rendering visualizations of high-resolution 3D CT datasets have been produced in QuickTime VR format for self-study by medical and physiotherapy students. The images can be accessed on any network-connected computer with the free QuickTime Player installed. As demonstrated by this exhibit, the user can freely rotate the volume around both vertical and horizontal axes by dragging the mouse in the image. In addition, the user can easily zoom in and out. The images produced so far include the heart and great vessels as well as parts of the musculoskeletal system. The use of semi-opaque structures facilitate the presentation of, e.g., the relationship between coronaries and heart chambers or between patella and femur. In preliminary evaluations, the students give the material high ratings. Conclusion: Easy access over the Internet and good interaction capabilities on low-end computers make this format attractive as an aid for anatomy learning.

A new software platform for interactive vertebra radioanatomy and CT guided interventions learning S. Aubry, A. Pousse, P. Sarliève, E. Delabrousse, L. Laborie, B. Kastler; Besançon/FR (radio.aubry@free.fr)

Learning Objectives: To become familiar with advanced software for 3D interactive radio-anatomy learning. To learn about basics in rachidian radio-anatomy. To experience fundamentals of simulated CT guided interventions. Background: The range of rachidian CT guided interventions is widening from day to day. This practice requires a perfect vertebra radio-anatomy knowledge and a high degree of interventional procedure culture. We present a software platform dedicated to vertebra radio-anatomy and CT guided interventions learning. Procedure Details: Based on 3D high resolution modelisation of vertebra segments and of their vasculonervous environment from multidetector CT acquisitions, the presented tool simultaneously offers multiplanar reconstruction (MPR), 3D surface rendering, objects outlining on MPR. OpenGL based development allows interactive shading such as lighting or opacity modifi cations. Furthermore, Virtual 3D objects have been inserted in the volume in order to simulate the best of rachidian CT guided interventions (infi ltration, cementoplasty, RF). Conclusion: This 3D modelisation package has the potential to improve radiologist's knowledge of the spine. Radiologists are thus able to virtually practice approaches aimed at safe planning of a variety of CT guided interventions.

Automatic segmentation of the rectal tube in computer-aided detection for virtual colonoscopy P. Boda, S. Agliozzo; Turin/IT (piergiorgio.boda@i-medlab.com)

Purpose: Computer-aided detection (CAD) for virtual colonoscopy (VC) is a tool that allows to detect polyps from VC exams. During the exam, a rectal tube (RT) is placed in the patient for air insuffl ation. This tube is the origin of false positive (FP) detections in the CAD system. We present a method for the automatic segmentation of the RT. Methods and Materials: Two types of RTs were used, which differ for their diameter and the plasticity. The fi rst RT (RT1) has a maximum diameter of 14 mm, whereas the second one (RT2) has a diameter of 8 mm and is more fl exible. Exams were acquired on a multislice helical CT scanner with a tube current of 50 mA at 120 kV, a slice thickness of 1.25 mm and an interval reconstruction of 0.6 mm. Patients were scanned in both supine and prone positions, after bowel cleansing and air insuffl ation. We studied 15 cases, for a total of 30 CT scans, four of them with RT1s and the rest with RT2s.

The algorithm detected 96% of RTs (29/30) and in all of these cases RTs were completely tracked. It failed once for a RT of the second type. The visual inspection of this case showed that the lumen of the RT was almost entirely fi lled with fecal residus.

We developed a robust automatic method for the segmentation of two types of RTs for CAD for VC.

Organic re-circulation of the information on network ( The purpose of this study is to develop a CT scanner system to reproduce key images that are specifi ed in a prior diagnosis.

The CT scanner retrieves a dedicated DICOM object from an image server and extracts a scan protocol of a previous study for application in the present study. The object is associated with a series of prior studies and includes information about scan protocol, scan range and the position of key images in the series. After acquiring a CT localizer in the present study, the operator registers the CT localizer to a prior one in the object, in order to fi t the patient's position using the anatomical landmarks. This operation enables the operator to fi t the scan range and image reconstruction range automatically. The CT scanner creates the new dedicated DICOM objects associated with the present study that have spatial offset value for comparable images to prior key images. Results: The acquired images have same scan conditions and same position of prior images within one slice difference.

We developed a CT scanner that makes it easy to acquire comparable images to those of a prior study. A time of additional operation of current study does not give much effect for study throughput of the CT system. Now, we are planning to standardize this dedicated object to make interoperability between different vendors and modalities.

Image retake analysis in digital radiography using DICOM header information E. Vano, J.I. Purpose: Retake analysis is a key aspect in any quality assurance programme and a basic tool to avoid unnecessary doses to patients in a radiology department. A methodology to automatically detect potential retakes using DICOM header information is presented. Methods and Materials: A system called QCONLINE was developed to help in the management of images and patient doses in a digital radiology department. Images are sent to the PACS and to a dedicated workstation where the QCONLINE runs. DICOM header information is extracted and transferred to a database. Relevant images can also be archived for inspection. The initial criterion for potential retakes was that 2 or more images have the same patient ID, modality, description, projection and date. This criterion was applied over the 3,742 abdomen and 4,236 chest images. A sample of the images was assessed to determine the goodness of the method.

The initial rejection criteria lead to a 15.4% retake rate in the abdomen examinations and a 4.5% for the chest examinations. After a thorough analysis of the supposed repeated images, the need for additional criteria such as orientation of the cassette (landscape/portrait) was demonstrated. The fi nal retake fi gures were roughly 50% of the automatic fi ltering from the database. Conclusion: Automatic retake analysis is a critical aspect in digital radiology. It allows detecting defi ciencies like wrong identifi cations, positioning errors, wrong radiographic technique, bad image processing, equipment malfunctions, artefacts, and so on. In addition, retake images fi ltered automatically and collected can be used for continuous training of the staff.

Feasibility of showing radiologic images on iPOD: Can Pod save the space? H. Funatsu, H. Takano, M. Kogure, A. Imamura, T. Kasai; Chiba/JP Purpose: iPOD, a portable media player, is capable of displaying images and movies. Carrying radiologic images in iPOD would be useful for educating residents, communicating with other radiologists or referring physicians, or informing patients at bedside. The purpose of our study is to evaluate lesion conspicuity on iPOD. Methods and Materials: Fifty sets of key images of either computed tomography or magnetic resonance imaging were randomly collected from computerized database in our department. Any lesions equal or less than 10 mm in diameter were excluded while collecting images. These 50 images with any fi ndings and 50 images without any fi ndings were installed on iPOD. Size and site of the each lesion were recorded. Five blinded radiologists reviewed the images both on iPOD and DICOM viewer with a 4-week interval between sessions. Conspicuity of the lesions was evaluated by using response receiver operating characteristic (ROC) curve analysis. (d-ust@yandex.ru) Purpose: To determine optimal compression settings and parameters for MR image compression. Methods and Materials: Investigation included 40 patients with various pathologies and consisted of mathematical and visual approaches. The mathematical approach included searching for the Quantitative Quality Index of compressed MR images (with analysis of currently approved quality index-Compression Ratio), compressibility tests, estimation of coders behavior. Visual image evaluation was performed on nine 12-bit head and spine MR images by four observers. Test images were compressed in JPEG, JPEG2000, JPEG-LS at various quality settings (q). Results: Image Compression Ratio (e.g. 8:1, 10:1 etc). is often used as a term equal to Image Quality, but it is unacceptable, because the visual quality of images with the same compression ratio may widely vary. Visually lossless threshold depends on resolution (the lower resolution the higher quality settings required) and body zone (e.g. compressibility of spine images is better than head images). In our study the visually lossless threshold was between q JPEG = 85-92 and q JPEG-LS = 82-94 for four observers. JPEG-LS was the best coder for high quality MR images compression, while JPEG2000 is concluded to be unfi t. JPEG shows a little worse result than JPEG-LS. Conclusion: Compression Ratio cannot be Quantitative Quality Index. In visual analysis, JPEG-LS provided the best image quality with maximum compression. JPEG can be still useful due to good compatibility and high quality. JPEG2000 seems unacceptable because of high resolution and high compression orientation.

Quantitative evaluation of nodule kinetics using temporal subtraction in dynamic chest radiography with a fl at panel detector Y. Tsuchiya 1 , Y. Kodera 2 ; 1 Shizuoka/JP, 2 Nagoya/JP (yuichiro-rt@k9.dion.ne.jp)

Purpose: This study was performed to develop a method of using a temporal subtraction technique for evaluating the quantitative kinetic function of a lung nodule by dynamic chest radiography, and to investigate the clinical application of our technique by using a simulated nodule. Methods and Materials: Dynamic chest radiographs (1344×1344, 12 bit, 3 fps, 10 sec) were obtained using a modifi ed fl at-panel detector system (CXDI-40G, CANON Inc, Tokyo, Japan). For respiratory phase synchronization, analysis of diaphragm kinetic was performed, and continuous subtraction in the expiratory phase was performed to obtain a temporal-subtraction image as output. The clinical effectiveness was investigated using radiographs of eight healthy volunteers (22-54 y/male) with a simulated nodule. The range of the enhanced region that appeared on the output image was manually measured. The differences between the known kinetic amount and result were calculated as detection error. Signifi cance of difference was then evaluated by paired t-test.

The movement tracks of the nodule could be visualized as a white region on the output image. The detection rate of the radiographs with 8 nodules was 75% (6/8). The maximum difference of ranges that were measured was less than 4 mm; the average of the absolute value of the difference was 3.69±4.82 mm. No statistically signifi cant differences were found between the known and measured amounts (p=.067). Conclusion: Dynamic chest radiograph with our computer analysis can clarify kinetic information regarding nodules and is effective as a screening examination for checkup or initial planning of radiation therapy.

Imaging biomarkers in colorectal cancer: Texture analysis of hepatic CT B. Ganeshan, K.A. Miles, R.C.D. Young, C.R. Chatwin; Falmer/UK (b.ganeshan@sussex.ac.uk) Purpose: To assess the potential for computer analysis of liver texture during CT to provide biomarkers for patients with colorectal cancer and to identify possible biological correlates for relevant texture features. Methods and Materials: A feasibility study comprised 27 patients undergoing CT after primary resection of colorectal cancer, followed by an evaluation group of a further 32 patients. Hepatic CT perfusion and survival data were available for both groups, with fl uorodeoxyglucose PET results accessible in the evaluation group. Texture was assessed within regions of interest manually constructed over apparently normal liver whilst excluding major blood vessels and fat, and comprised band-pass image fi ltration at different spatial frequencies, followed by quantifi cation of liver texture.

The feasibility study demonstrated that liver texture during the portal phase correlated with the hepatic perfusion index (r=-0.50, p=0.0074), and survival (r=0.49, p=0.0095). In the evaluation study, texture in apparently normal liver tissue in patients with hepatic metastases was different from patients with no tumour recurrence on unenhanced (p=0.026) and arterial phase images (p < 0.04), and from patients with extra-hepatic disease on unenhanced images only (p=0.014). Among patients with no visible liver metastases on CT, texture analysis of portal phase images could identify those with extra-hepatic disease on PET (p=0.0035) and impaired survival (p=0.0074). The hepatic phosphorylation of glucose was identifi ed as a possible biological correlate for texture (r=-0.59, p=0.0062).

Conclusion: Texture analysis of hepatic CT images obtained during routine clinical practice can provide biomarkers that refl ect hepatic physiology and identify patients with extra-hepatic disease and poor survival.

Novel approach to evaluate regional parenchymal pulmonary and aortic blood supply selectively with self-developed dual phase perfusion software in 64-slices CT X. Xie, G. Zhang, Y. Chen, Z. Li; Shanghai/CN (adrianxie@163.com)

Learning Objectives: To demonstrate that pulmonary arterial phase images and aortic phase images can be acquired with 64 slices CT. To develop Windows-based software for processing semi-qualifi ed dual phases perfusion. Background: Pulmonary blood supply includes pulmonary and systematic circulation. Regional blood supply imbalance is complex in some diseases, such as COPD.

With complicated scanning technique, non-contrast images, pulmonary arterial phase images and aortic phase images were acquired in one breath-hold with 64slices spiral CT. Delay time was determined by a time-density curve. Contrast was pushed forward by saline for better enhancement. Then, pulmonary arterial phase and aortic phase data sets can be acquired. Windows based software (DualX 2.0) was developed to analyze these selective dual phase images with Delphi 9.0. Procedure Details: After image correction, pulmonary enhancement and bronchial enhancement can be calculated by subtraction technique. Then, pulmonary ratio was calculated, which is the proportion of pulmonary enhancement in total enhancement. Pseudo-color map also can be rendered to illustrate these parameters over non-contrast images. Conclusion: Pulmonary phase perfusion and aortic phase perfusion can be evaluated separately. Purpose: To compare the dynamic information obtained from contrast-enhanced ultrasonography (CEUS) and contrast-enhanced magnetic resonance (CEMR) on two experimental tumor models exhibiting notable differences in vessel anatomy. Methods and Materials: Six animals subcutaneously injected with a carcinosarcomatoid (A17) cell line and six animals injected with a carcinoma (BB1) cell line underwent CEUS and CEMR. CEUS was performed on a Technos (Esaote, Italy) with a bolus injection (0.01-0.05 ml) of sulphur hexafl uoride microbubbles (SonoVue, Bracco, Italy) into a tail vein. The curve of enhancement (time-intensity) obtained by locating a ROI over the tumor was used to calculate maximal intensity (Mi) and slope (S). CEMR was performed on a Biospec scanner (Bruker, Germany) by injecting Gd-DTPA-albumin (Contrast Media Laboratory, University of California, USA). By locating a ROI over the tumor, we calculated fraction plasma volume (fPV) and transendothelial permeability (kPs). All the tumors were removed and analyzed histologically and immunohistochemically (CD 31). The vascularity of the two different tumor histotypes was comparatively evaluated by immunohistochemical, CEMR and CEUS analyses. Results: Considering the viable areas of the tumor, the vessels of A17 were signifi cantly (P < 0.00001) more numerous and smaller than those in BB1 tumors. CEMR fPV and kPS parameters were signifi cantly (P=0.00001) higher for the A17 tumors than for the BB1 tumors. CEUS Mi and S values were smaller in the A17 tumors than in the BB tumors (P=0.002). Conclusion: Our data demonstrate that particular histologic features, such as collapsed intratumoral vessels, can lead to a mismatch between CEUS and CEMR in studying tumor vascularization. Learning Objectives: To discuss the optimisation of acquisition parameters to maximize the ability of Ferumoxtran-10 enhanced MR imaging (USPIO-MRI) at 3 Tesla. To demonstrate tips and tricks for evaluating USPIO-MRI in combination with dedicated software for visualizing 3D localisation of LNs. Background: USPIO-MRI is shown to be extremely accurate for assessment of the LN status in prostate cancer patients. Since positive LN smaller than 4 mm can be accurately detected with USPIO-MRI, appropriate high-resolution imaging is essential to maximize its clinical usefulness. Clinical 3 T whole-body MR system, which is increasingly becoming available, is expected to enable imaging with a higher spatial resolution. Aids with dedicated computer software are now essential in evaluation for numerous high spatial resolution images. Imaging Findings: The exhibit is based on our experiences of USPIO-MRI at 3 T in years, including 3 T-MRI scanner with total imaging matrix. Positive LNs with 2 to 3 mm in diameter can now clearly visualised on USPIO-MRI at 3 T. Thanks to multi-channel capability, both T1 and T2*-weighted image can be obtained with 3DFT-volume data acquisition, which enable to acquire isotropic voxel T2*-weighted images, as well as T1-weighted images. These volume data are evaluated on dedicated software for visualizing 3D localisation of LNs. Conclusion: Combination of novel techniques, 3 T-MRI with TIM technique and USPIO, enable to visualise tiny positive LNs on MRI. Optimisation of the acquisition parameter is essential to maximize the ability of USPIO-MRI. The help of computer technology is vital in handling numerous data to be evaluated. Purpose: To assess the effi cacy of harmonic gray-scale ultrasonography using second-generation contrast agents (SonoVue) in evaluating the response of hepatocellular carcinoma (HCC) after percutaneous treatment, and to compare the fi ndings of this imaging modality with those of dynamic magnetic resonance imaging (MRI).

A total of 27 patients with HCC treated by transarterial chemoembolization (16), ethanol ablation (10) or radiofrequency ablation (1) were included in the study. All of them were examined with second-generation contrast agents ultrasonography (CUS) one month after the last percutaneous treatment. Vascular fi ndings at CUS were compared with the results of dynamic MRI. Contrastenhanced MRI fi ndings were taken as the gold standard. Tumoral response criteria considered at CUS were: (1) persistence or absence of tumoral enhancement during arterial phase, (2) necrotic tumoral size. Results: CUS and MRI, performed one month after HCC percutaneous treatment, found complete response in 13 of the 27 patients (48%) and no response in 14 patients (52%), respectively. Comparing both imaging techniques, we obtained an agreement of 85% (kappa 0.70), a sensitivity of 85%, a specifi city of 86%, a positive predictive value of 85%, a negative predictive value of 86% and an accuracy of 85%. In 4 cases, CUS and MRI found different results. Conclusion: CUS is useful to detect residual HCC when compared with dynamic MRI results. Because of its low cost and high disponibility, it may reduce the frequency of dynamic MRI in the follow-up of treatment response. Learning Objectives: To provide an educational review of the multifactorial elements of contrast-induced nephropathy. To review the current literature on etiology and prevention of contrast-induced nephropathy. To provide evidence-based approach/algorithm when assessing patients undergoing contrast enhanced procedure. To establish a protocol for patient care and follow-up. Background: Contrast-induced nephropathy has become an important cause of iatrogenic acute renal impairment and currently ranks as the third most common cause of hospital-acquired acute renal failure. Although clinical presentation of CIN is well described, precise mechanisms and management strategies for this complication continue to be a matter of debate. The incidence of CIN (Contrast Induced Nephrotoxicity) is dependent on both the defi nition of CIN and the patient population investigated. The incidence of nephropathy is low in the general population, but patients with increased risk (patients with renal impairment and diabetes) have reported signifi cantly higher frequency (12-50%). Procedure Details: Through a medline literature search and review of a number of current guidelines, we will establish an algorithm of best practice for all patients undergoing contrast-enhanced procedures. We will assess the current evidence on potential prophylaxis (prehydration, acetylcysteine, bicarbonate, fenoldopam, discontinuation of nephrotoxic medications prior to contrast-enhanced scans) and those patients that should be targeted for these treatments.

We provide a thorough and concise review of this intricate area, which could be applied in all radiology departments to optimise patient care in a practical manner.

Effi Purpose: To assess the diagnostic accuracy of Gd-DOTA MRA over TOF MRA for non-coronary arterial disease by comparing the percent agreement at the subject level of each MRA method with X-ray angiography (defi ned as number of segment scores in agreement/ total number of segments evaluated for the subject x100).

Multicenter, open-label, fi xed sequence, paired trial in 100 subjects > 18 years [64 men, 36 women; mean age (±SD) 64.5 ± 13.7 years] with suspected non-coronary arterial disease and scheduled to undergo X-ray angiography were included and received an iv bolus of Gd-DOTA 0.1 mmol/kg. Results: The regions imaged for arterial disease were: renal (33.0%); aorto-iliac (31.0%); femoral (15.0%); carotid (12.0%); popliteal (6.0%); and calf ( 

The essence of iodinated contrast media: What every radiologist must know (2) To discuss the factors that infl uence image quality.

(3) To evaluate the risk of anaphylaxis, nephrotoxicity or nonrenal adverse reactions, and to discuss the role of pre-medication regimen.(4) To be aware of the decisions one has to make before injecting iodinated CM. (5) To become acquainted with the appropriate treatment of such adverse reactions. (6) To discuss special situations (dialysis, metformin, pregnancy and lactation). Background: Iodinated contrast media (CM) are sterile iodine-containing solutions used in almost all diagnostic imaging methods. Since their advent in the 1950s, they have revolutionized diagnostic imaging. Although the diagnostic value of CM is enormous, other less desirable side effects also occur. Procedure Details: The purpose of this review is to address some of the main concerns that arise with the day-to-day use of iodinated CM. This presentation is divided by topics. It provides guidelines recommending precautions to prevent possible iodinated CM reactions. The authors discuss the need for informed consent and measurement of renal function, as well as the risk factors that may predict adverse events, and how to deal with patients who have had a prior reaction. The types and treatment of adverse reactions are discussed. Conclusion: Although iodinated CM are safe and widely used, adverse events occur and questions remain about their use, safety and interactions. Every radiologist should be intimately familiar with CM.

Sixty Methods and Materials: Ninety consecutive patients (53 men, 37 women; mean age: 57 years) were randomly assigned to one of three CTA protocols: in group 1: 70 ml of contrast medium (300 mg iodine per milliliter [mgI/ml]; fl ow rate: 4 ml/s); in group 2: 60 ml of contrast medium (350 mgI/ml; fl ow rate: 4 ml/s); and in group 3: 50 ml of contrast medium (350 mgI/ml; fl ow rate: 5 ml/s) were intravenously administered. All contrast medium applications were followed by 20 ml of saline fl ush. The attenuation in Hounsfi eld Units (HU) was assessed from the ascending aorta to the thoracic aorta at the level of the aortic hiatus at fi ve different locations.

The patients of all the three study groups showed diagnostically acceptable attenuation values of the thoracic aorta. The overall mean aortic attenuation was 258±54 HU in group 1, 274±83 HU in group 2 and 277±102 HU in group 3. Group 1 had the most constant opacifi cation of the thoracic aorta and showed a trend to lower mean and maximum, but higher minimum and median attenuation values than groups 2 and 3; group 2 and group 3 showed a trend to lower attenuation values in the distal thoracic aorta than group 1. Conclusion: Different contrast medium CT protocols were evaluated and this resulted in acceptable diagnostic attenuation values in CTA of the thoracic aorta. Therefore, 64-detector row CT allows reducing the amount of contrast medium down to 50 ml, when an iodine concentration of 350 mgI/ml and a fl ow rate of 5 ml/s are used.

The basic procedural knowledge of ultrasound contrast agents: A how-todo DVD Rom-based audiovisual teaching guide P.S. Zoumpoulis, I. 3. To present a step-by-step visual guide on how to prepare the patient, how to administer the solution, how to make control adjustments on US machine, and how to evaluate the sonographic fi ndings. 4. To establish a safe and credible procedure that minimizes complications and ensures true-positive results. Background: The interaction between the "bubbles" and the US beam is explained with analytical drawings and real-time US videos. Procedure Details: Contrast-enhanced ultrasound improves the detectability of pathology by revealing regions of increased vascularity. This medical e-book illustrates the steps taken to perform an ultrasound exam with use of ultrasound contrast agents. A detailed description of ultrasound contrast agents, how to prepare the solution, how to prepare the patient, administration of the solution, control adjustments of US machine to enable high-analysis contrast detection such as MI, TGC, gain, depth and focus and sonographic appearance of ultrasound contrast agents are provided in a user-friendly manner. The proper technique is demonstrated step by step. Educational double video presentations included a simultaneous presentation of the real-time ultrasound exam and the examiner's technique. Conclusion: User-friendly DVD Rom-based visual guide with step-by-step procedural instructions on how to perform an ultrasound examination with ultrasound contrast agents. Purpose: To evaluate the mechanisms of cytotoxicity of an iodinated contrast medium on renal tubular cell cultures. Methods and Materials: LLC-PK 1 -cells were incubated with iomeprol and corresponding mannitol solutions (4.7-75 mg I/ml, 2-24 h). Metabolic activity was assessed with 3-(4.5-dimethyl-2-thiazolyl)-2.5-diphenyl-2H-tetrazoliumbromid (MTT)-assay. The Trypan-blue test was used to assess cell viability. To detect apoptosis, an ELISA for the determination of oligonucleosomes in the cell lysate was performed. 5-Bromo-2'-deoxyuridin (BrdU)-incorporation into the DNA was measured to assess proliferation. Results: Iomeprol induced a time-and dose-dependent inhibition of MTT-conversion (64-14%, at 4.69-75 mg I/ml at 24 h; 54-41%, at 2-24 h at 18.75 mg I/ml), which was signifi cantly stronger than that induced by mannitol (99-47% at 24 h, p < 0.001).

After 24 h incubation with iomeprol and a recovery time of 2 h after removal of the contrast medium, there was only a small inhibition of MTT-conversion (96% and 89% at 4.7 and 75 mg I/ml, respectively). There was no signifi cant increase in the number of necrotic cells (8% in control; 8% and 10% after 24 h incubation with iomeprol at 37.5 and 75 mg I/ml, respectively; p> 0.05). As an indicator for apoptosis, the number of oligonucleosomes increased signifi cantly (20% difference to control at 37.5 mg I/ml after 24 h, p < 0.05). Iomeprol induced a signifi cantly stronger inhibition of proliferation than mannitol (92% and 68% vs. 99% and 82% at 18.75 and 37.5 mg I/ml, respectively; 24 h, p < 0.001).

The iomeprol-induced inhibition of MTT-conversion is mostly reversible, and is not associated with cell necrosis. The irreversible part may be due to apoptosis and decreased proliferation.

Evaluation of low-dose contrast protocols for 3D-CTA of the aorta using 64-row multislice CT T. Sakamoto 1 , D. Utsunomiya 1 , S. Okumura 1 , J. Urata 1 , K. Anami 2 , A. Taniguchi 2 ; 1 Kumamoto/JP, 2 Bunkyo-ku,Tokyo/JP (taka-sakamoto@skh.saiseikai.or.jp) Purpose: 64-row multislice CT provides detailed data over a wide range in a short time, and reducing the amount of contrast medium used for 3D-CTA has been attempted at many facilities. We conducted studies to investigate the optimization of contrast enhancement and to evaluate the usefulness of low-dose contrast protocols for 3D-CTA of the aorta, based on clinical data. Methods and Materials: 3D-CTA of the aorta was performed in 78 patients. Nonionic contrast medium (300 mgI/mL) was injected at a rate of 3.0 mL/s, followed by a 20 mL saline fl ush injected at 3.0 mL/s. Two protocols that differed in the amount of contrast medium injected [protocol A: 100 mL (26 patients) and protocol B: 50 mL (52 patients)] were evaluated and compared. The mean CT numbers and SD values in the ascending aorta, descending aorta, pulmonary artery, diaphragm, aortic branches, and external iliac artery were compared. The appropriate dose of iodinated contrast medium per kilogram body weight was also investigated for protocol B. 

The fi ndings of the present study indicate that the appropriate dose of contrast medium is 250 mgI/kg body weight to ensure optimal contrast enhancement in aortic 3D-CTA.

Evalutation Methods and Materials: One hundred and thirty-four patients with 148 nodules of HCC treated with TACE (n. 38) and with RFTA (n.110) were admitted to our department for follow-up. Nodules treated with RFTA were divided retrospectively into two groups: 1) Group 1 (41/110): immediate post-ablation evaluation using CEUS was performed and, when necessary, immediate contrast-enhanced ultrasound-guided targeted re-treatment was carried out; and 2) Group 2 (69/110): CEUS was performed only for follow-up. Therapeutic response was evaluated at one month with dynamic CT and CEUS. Sensitivity and specifi city of CEUS and dynamic CT were calculated. Results: After RFTA, complete response was observed in 92.7% (group 1) and in 78.3% (group 2) with dynamic CT and in 92.7% (group 1) and 82.6% (group 2) with CEUS. Sensitivity and specifi city of CEUS were 83% and 100%. After TACE, complete response was observed in 47.4% of nodules with dynamic CT and in 39.5% with CEUS. Sensitivity and specifi city were 87% and 100% for dynamic CT and 100% for CEUS. Conclusion: Contrast-enhanced ultrasound may be a more suitable technique to evaluate intratumoral residual blood fl ow following TACE treatment. Evaluation of the results between the two groups who underwent RFTA showed a signifi cant difference in the ablation success rates.

Is contrast-enhanced ultrasound useful? Principal radiological and clinical applications D. Volpe, N. Volpe, A. Saponaro, N. Masiello, P. Neri, A. Carriero; Novara/IT (dvolpe@sirm.org)

Learning Objectives: To show the technical principles underlying ultrasound (US) contrast agents, imaging fi ndings, and principal radiological and clinical applications. Background: The introduction of contrast agents has led to one of the most important advances in ultrasonography. US contrast agents are intravenously injected substances that are distributed by the blood fl ow to all organs, where they modify the characteristics of the tissues by increasing their ultrasonographic refl ectance. Given the different types of vascularization of normal and pathological tissues, they offer a better means of characterizing focal lesions than B-mode echography. Procedure Details: Contrast-enhanced US is more accurate than conventional echography in determining the number and size of focal lesions, and revealing capsular involvement, because it reduces the number of false-negative results. This more precise classifi cation of lesions has a considerable diagnostic and prognostic impact. We provide an overview of its principal radiological and clinical applications: focal lesions, trauma of solid abdominal viscera, vescicoureteral refl ux, and vascular diseases.

The introduction of second-generation contrast media is changing the diagnostic perspective by giving radiologists an effective product of immediate use that eliminates all interpretative doubts and facilitates diagnosis.

Effects of non-ionic iodinated contrast media (CM) on patient heart rate during intra-cardiac or intra-arterial injection I. Schmid 1 , D. Purpose: To compare heart rate (HR) and systolic/diastolic blood pressure (BP) after intra-cardiac or intra-arterial injection of a non-ionic low-osmolar CM (Iomeprol) and a non-ionic iso-osmolar CM (Iodixanol).

Double-blind, randomized studies were conducted in 120 patients undergoing cardiac angiography (CA) and 96 patients undergoing peripheral intra-arterial digital subtraction angiography (IA-DSA). Patients undergoing CA received Iomeprol-350 (n=60) or Iodixanol-320 (n=60). HR and systolic/diastolic BP was determined before and after initial injection during left and right CA (LCA and RCA) and left ventriculography (LV). Differential effects were assessed using t-tests. Patients undergoing IA-DSA received Iomeprol-300 (n=49) or Iodixanol-320 (n=47). HR and systolic/diastolic BP were evaluated before and after the fi rst 4 injections. Repeated-measures ANOVA and t-tests compared mean HR changes across the fi rst 4 injections and after the fi rst injection, respectively. Monitoring for adverse events (AE) was performed in both studies. Results: No signifi cant differences between Iomeprol and Iodixanol were noted in terms of mean changes in HR during LCA (p=0.8), RCA (p=0.9), and LV (p=0.8).

In patients undergoing IA-DSA, no differences between CM were noted for effects on mean HR after the fi rst injection (p=0.6) or across the fi rst 4 injections (p=0.2).

No differences between CM were noted regarding effects on systolic or diastolic BP. Purpose: To evaluate the diagnostic advantages of intravenous USPIO administration on T-staging of uterine carcinoma. Methods and Materials: Seventeen female patients referred for gynecological carcinomas, 11 with corpus uterine cancer and 6 with cervical carcinoma underwent MR scan of the pelvis on a 1.5 T magnet. GRE T2*W sequences (TR/TE/FA/matrix/ acq. time: 1800 msec/15 msec/30°/230x512/13.51 min) were acquired on multiple planes before and 24 hours after iv administration of 2.6 mg/kg of body weight of Sinerem (Guerbet, Paris, France). Image analysis were performed by consensus by two radiologists and it included qualitative and quantitative analysis of signal intensity (SI) of both normal myometrium and neoplastic lesions before and after Sinerem administration. S/N and C/N were calculated. Modifi cation of T-staging in images obtained after Sinerem administration was also evaluated. Statistical analysis was performed using Wilcoxon test (p < 0.05). Results: Qualitative analysis showed a signifi cant decrease of SI of normal myometrium after Sinerem administration leading to a better lesion conspicuity. Quantitative analysis showed a statistically signifi cant difference between SI of myometrium on plain and Sinerem-enhanced MR images assessed by means of t-test. C/N between lesion and normal myometrium signifi cantly increased following Sinerem administration. In 13 patients Sinerem-enhanced images provided additional information leading to more accurate T staging. Conclusion: Intravenous injection of Sinerem provides a signifi cant decrease of SI of normal myometrium with higher C/N between neoplastic lesion and normal myometrium increasing the conspicuity of neoplastic lesions.

The Learning Objectives: We will explain the etiology of round ligament varices (RLV) in pregnancy and elucidate why they may have a similar clinical picture to an irreducible hernia. Knowledge of this condition is clinically signifi cant as this may be misdiagnosed as an obstructed hernia, leading to unnecessary surgical intervention during pregnancy. As ultrasound (US) is the imaging modality of choice, we will review the US features that establish an accurate diagnosis. Background: Anatomically the round ligament extends from the lateral uterus to the labium majorus containing veins, arteries, lymphatics and nerves. Pregnancy promotes increased venous fl ow and reduced venous tone, thereby predisposing patients to varicosities. Clinically, RLV and inguinal hernias can be indistinguishable with similar anatomical sites, comparable positive cough impulses and both demonstrating reducibility with positional change. Imaging Findings: Dilatation of the veins of the broad ligament and ovarian plexi cause a clinical entity called the pelvic congestion or pelvic pain syndrome. When this process extends into the round ligament, it becomes a more diffi cult diagnosis. However, the ultrasound and Doppler appearances of this condition are unique and can be easily recognized.

The true incidence of round ligament varices is unknown but is suspected to be higher than the small amount of reported cases in the literature Through our series, we demonstrate that the diagnosis of RSV should be entertained in pregnant women presenting with a painful groin mass, and ultrasound should be performed in such cases to avoid unnecessary surgical exploration.

Hypointense ovarian lesions on T2-weighted magnetic resonance imaging: Radiologic-pathologic correlation M. Takeuchi Learning Objectives: To demonstrate various benign and malignant ovarian pathologies presenting as hypointense masses on T2-WI with pathologic correlation. Background: Hypointensity on T2-WI is an unusual fi nding of ovarian tumors and form a special diagnostic category. These lesions have some histopathologic characteristics, which shorten the T2 relaxation time of tissues and help to make differential diagnosis.

Imaging Findings: T2 shortening due to dense collagenous tissue was observed in benign fi brous tumors such as fi bromas, thecomas, adenofi bromas, and Brenner tumors, but rarely also observed in malignant tumors such as Krukenberg's tumors with reactive stromal proliferation and malignant carcinoid tumors with neoplastic stromal proliferation. Intense contrast-enhancement refl ecting hypervascularity of malignant tumors may be the diagnostic clue. Rare solid malignant tumors with honey-combing appearance fi lled with mucinous materials or coagulated necrosis such as mucinous tumors or solid clear cell carcinoma may mimic benign fi bromas, and reticular contrast-enhanced internal patterns may suggest these tumors. Coagulated necrosis with hemorrhagic clots in malignant germ cell tumors may show hypointensity, and elevation of specifi c tumor markers may be helpful for diagnosis. Mucinous, or viscous proteinous materials in mucinous cystic tumors, and struma ovarii with colloid cysts may cause hypointensity in the cystic portions. Repeated intra-cystic hemorrhage in endometrial cysts may cause hypointensity as "shading", but similar appearance may also be observed in some dermoid cysts and tubo-ovarian abscesses. Conclusion: Hypointensity on T2-WI may usually suggest its benign nature, but some malignant tumors also show hypointensity and preoperative diagnosis is important.

www.CancerStaging.info: A free and customized online tool to facilitate quick and accurate staging of common female pelvis cancers based on imaging fi ndings R. Talanow, S. Shah; Cleveland, OH/US (roland@talanow.info)

Purpose: To provide a free, comprehensive, web-based, on-the-fl y solution which is easy to use and aids in accurate staging of common female pelvis cancers, based on imaging fi ndings.

The program runs on a 700 MHz Pentium II quad processor with Microsoft Server 2003 operating system. Script languages include PERL, Javascript, DHTML. Information about tumor classifi cations is stored in a MySQL database. On-the-fl y staging is done by calculating and comparing the information provided by the user with the tumor classifi cation database saved on the server. The user may provide the information in several offered modes for the user's convenience. Output of information is also offered in several modes to increase fl exibility and better integration into the reader's workfl ow.

Results: This web-based and customized program easily integrates into the radiologist's daily work from any monitor or PACS station. The interface is fl exible and easily adapts to the individual physician's preferences by seamlessly incorporating into the workfl ow. Furthermore, it offers hyperlinks to more comprehensive websites for access to therapeutic and prognostic information for a particular malignancy. Conclusion: www.CancerStaging.info is a free, web-based, customized tool that allows staging of common female pelvis cancers (i.e. cervical, ovarian, uterine and endometrial) based on imaging fi ndings, with hyperlinks to more informative and in-depth websites. It is an intuitive, user friendly educational program which makes staging of common female pelvis malignancies easy and accurate. Learning Objectives: To illustrate the value of color Doppler US as an adjunct technique in the evaluation of those uterine pathologies in which detection and characterization of vascular structures allow an early diagnosis. Background: Ultrasonography (US) is the initial diagnostic modality in gynecological assessment. The transvaginal via is recommended, except in contraindicated cases (intact hymen, pregnancy of more than three months, and so on). Color Doppler US as an adjunct technique has become an effective tool in the evaluation of those uterine pathologies in which detection and characterization of vascular structures allow establishing early diagnosis, when the gray-scale ultrasound images are nonspecifi c or confusing. In this exhibit, we describe the value of color Doppler US in the diagnosis of endometrial polyps, the distinction of leiomyomas and adenomyomas, the evaluation of de arteriovenous malformations, and the diagnosis of aneurysms and pseudoaneurysms. Imaging Findings: Color Doppler US contributes to the diagnosis of endometrial polyps by the identifi cation of vascular structures in the pedicle; permits the distinction between leiomyomas and adenomyomas bythe vascular distribution patron; plays an important role in the evaluation of de arteriovenous malformations, allows distinction from myomas with degenerative changes, and detects the presence of arteriovenous shunting. Color Doppler US also plays an important role in the diagnosis of aneurysms and pseudoaneurysms. Conclusion: Color Doppler US with conventional techniques and power-angio are very useful in early diagnosis and the follow-up of many uterine pathologies.

Benign cystic ovarian masses with solid components mimicking malignancy: Radiologic-pathologic correlation M. Takeuchi Learning Objectives: To demonstrate various benign ovarian pathologies presenting as cystic masses with solid components on imaging mimicking malignancy with pathologic correlation. Background: Solid components of ovarian cystic masses may usually suggest their malignant nature, but some benign pathologies may also show the similar appearances mimicking malignancy. Imaging Findings: Solid fi brous tumors (Brenner tumor and adenofi broma) coexisting with cystadenomas show characteristic hypointensity on T2-WI refl ecting dense fi brous proliferation. Small tiny cysts within hypointense solid portion (black sponge-like appearance) of adenofi broma are diagnostic. Mural nodules with intense contrast-enhancement and very high intensity on diffusion-weighted images (DWI) may suggest malignancy, but benign dermoid nipple may show surface slight contrast-enhancement and very high intensity on DWI. Solid portion of struma ovarii also show intense contrast-enhancement, and lobular appearance with hypointense colloid contents on T2-WI is characteristic. Benign cystadenomas may contain small papillary vegetations with no or slight contrast-enhancement. Pregnant decidual changes of endometriomas may show broad-based hyperintense mural nodules on T2-WI. Irregular clots within endometriomas may mimic malignant component, and the absence of contrast-enhancement on subtraction images is the diagnostic clue. Daughter cysts of mucinous cystadenomas, and ovarian parenchyma within peritoneal retention cysts may mimic solid mural nodules on CT or ultrasonography, and T2-WI can provide better tissue contrast for the correct diagnosis. Conclusion: Benign cystic lesions with neoplastic components (Brenner tumors, adenofi bromas, teratomas and vegetations), reactive components (decidualized endometriomas), and non-solid components simulating solid portion (mucinous daughter cysts) should be differentiated from malignancy to avoid excessive surgical procedure.

Malignant transformation of mature cystic teratoma: Analysis of imaging fi ndings and clinical data J. Kim, S. Park, J. Kim, K. Cho; Seoul/ KR (lola1024@freechal.com) Purpose: To evaluate the imaging fi ndings and clinical data predicting malignant transformation of mature cystic teratoma.

In 11 patients with histopathologically confi rmed diagnosis, we analyzed the CT and MR fi ndings with regard to the presence of soft tissue components, tumor size, the angle between the soft tissue components and the inner wall of the cyst (acute or obtuse), and the confi guration of the inner border (regular or irregular). Clinical and laboratory data including patient's age and tumor marker such as CA-125, CA 19-9, and AFP, were also analyzed.

In the analysis of the imaging fi ndings, nine (82%) of 11 tumors had soft tissue components and eight (89%) of nine soft-tissue-containing tumors showed an obtuse angle between the soft tissue components and the inner wall of the cyst. In nine (82%) patients, the maximum tumor diameter was greater than 10 cm and the patient's age was greater than 45 years. CA-125 was greater than 35 U/ml in six (67%) of nine patients and CA 19-9 was greater than 37 U/ml in three (75%) of four patients. Conclusion: Malignant transformation of cystic teratoma can be preoperatively predicted by combination of imaging fi nding and clinical data.

Spectrum of fi ndings of Mullerian duct anomalies at MRI P. Paolantonio, R. Ferrari, F. Iafrate, C. De Cecco, P. Lucchesi, A. Laghi;

Learning Objectives: To illustrate some crucial MRI technical features for the evaluation of normal uterine morphology and mullerian duct anomalies. To show spectrum of fi ndings of several mullerian duct anomalies at MRI. To illustrate MRI fi ndings useful in predicting the clinical impact of uterine anomalies in terms of infertility or risk of miscarriage. To illustrate MRI fi ndings useful for treatment regimens assessment. Background: Since 1988, the American Fertility Society (AFS) established a classifi cation of uterine malformations. Because mullerian ducts defects are the result of a spectrum of mullerian ducts non-fusion, defi cient development and/or defective canalisation of the uterine cavity, the process may become arrested at any point in development. A complete assessment of uterine anatomy is mandatory in order to evaluate the impact of uterine malformation on women fertility and also to plan the optimal strategy of treatment. Procedure Details: In this exhibit, we describe an optimised MRI protocol including high resolution T2 weighted TSE sequence acquired on dedicated oblique planes for the evaluation of uterine morphology. We describe MR fi ndings of several mullerian duct anomalies according to the AFS classifi cation with emphasis on different subtypes of septate uterus describing fi ndings useful to predict risk of recurrent miscarriage and to programme histeroscopical surgical treatment. Conclusion: MRI is a safe, non invasive and ionizing free method for diagnosis of uterine anomalies. MRI allows a complete evaluation of uterine morphology useful in surgical approach planning.

MRI of the pelvis in mullerian duct abnormalities: Is there a role in selecting patient for histerocopic metroplasty? P. Paolantonio 1 , F. Iafrate 1 , R. Ferrari 1 , C. De Cecco 1 , A. Carnevale 2 , C. De Angelis 2 , A. Laghi 1 ; 1 Latina/IT, 2 Rome/IT (paolantoniopasquale@hotmail.com)

Purpose: Selection of patient for histeroscopic metroplasty requires a complete assessment of uterine morphology usually achieved by laparoscopy that represent the gold standard in the evaluation of uterine morphology. The aim of our study was to assess the role of MRI in selecting patients with mullerian duct fusion defect for hysteroscopic metroplasty.

We prospectively investigate 25 females with known mullerian duct defect assessed at hysteroscopy. Examination were performed using 1.5 T magnet equipped with phased-array coil acquiring high-resolution TSE T2W sequence (TR: 3000 msec/ TEeff 190 msec / ETL: 29/ Matrix 256 x 512) parallel to the long axis of the uterus. Final diagnosis was assessed in all patients at surgery using laparoscopy in the assessment of uterine morphology. In 22 patients, hysteroscopic metroplasty was also performed. Image analysis was performed by two radiologist in a blind consensus fashion. They qualitatively evaluate morphology of both uterus and endometrial cavity. MR fi ndings were compared with laparoscopic and hysteroscopic fi ndings. Results: MRI revealed uterine abnormalities in all patients. In detail, 15 patients B D E F A G

were diagnosed as incomplete septate uterus, 5 as complete septate uterus, four patient as arcuate uterus and one patient as bicornuate uterus. MRI fi ndings were correct in all cases, as confi rmed by hysteroscopy and laparoscopy. Conclusion: MRI is a valuable tool in the evaluation of uterine morphology. Its use will help in sparing patients from laparoscopy, selecting patients for hysteorplastic metroplasty.

Diffusion-weighted MR imaging in uterine myometrial lesions with pathologic correlation K. Tamai, T. Koyama, N. Morisawa, K. Fujimoto, S. Fujii, K. Togashi; Kyoto/JP Learning Objectives: 1) To illustrate MR features of uterine myometrial lesions on diffusion-weighted images (DWI) in correlation with pathologic fi ndings. 2) To discuss the advantages and limitations of DWI and ADC measurement in evaluating uterine myometrial lesions. Background: DWI can provide tissue contrast based on diffusion motion of water molecules, different from that of conventional MR sequences. ADC values calculated from DWI are infl uenced by nuclear-to-cytoplasm ratio and cellular density that may be attributed to decreased ADC values of malignant tumors. Since DWI has been recently applied to the female pelvis, knowledge of its advantages and limitations is necessary for evaluating myometrial lesions. Imaging Findings: On DWI, the normal myometrium shows low intensity and the normal endometrium shows high intensity. The vast majority of ordinary leiomyomas and adenomyosis, which show low intensity on T2WI, also exhibit low intensity on DWI. In contrast, uterine sarcomas show prominent increased intensity on DWI. However, even benign lesions such as cellular leiomyomas and adenomyosis with proliferating ectopic endometrial tissues show high intensity on DWI, which can mimic malignancy. Thus, careful evaluation of T2WI is mandatory for avoiding misinterpretation. Although ADC values of these myometrial lesions are usually lower relative to the normal myometrium, distinction between benign and malignant based on ADC values may be diffi cult because of a considerable overlap. Conclusion: DWI and ADC measurements may have a limited role in distinguishing between benign and malignant myometrial lesions. However, careful interpretation of both DWI and T2WI may aid in estimating tissue characteristics of uterine myometrial lesions. Results: OVV was revealed in 65 (47.79%) patients. The frequent clinical complaints were: low abdominal pain, disturbance of menstrual cycle. In 66% of cases, a combination of OVV with structural changes in ovaries was noted (multicystic or polycystic ovaries, the syndrome of ovary inanition). Also, in 46% cases, along with ovarian structural changes the following were also noted: chronical infl ammatory disease in 46%, myoma in 28%, and endometriosis in 26%. In 82% OVV were noted bilaterally, in 12% on the left side, and in 6% on the right side. Based on the diameter and location of varicosis, we defi ned 3 degrees of OOV: I -one side dilatation of ovary vein to 5 mm, II -bilateral OVV and dilatation of plexus venus uterovaginalis from 6 to 10 mm, III -the dilatation above 10 mm in cases of total pelvic veins varicosis. Reno-ovarian refl ux was positive in 53% by Valsalvas maneuver. Conclusion: TVCD is an effective and noninvasive modality in the diagnosis of OVV as a cause of female infertility. In 66%, this pathology with secondary changes in ovaries was combined with various dishormonal gynecological pathologies. Learning Objectives: To evaluate several points to meet the patient selection guidelines in screening pelvic MRI for MR-guided focused ultrasound surgery (MRgFUS) of uterine fi broids. Background: Currently, all treatment options for uterine fi broids are invasive and require several days of hospitalization and a few weeks of recovery. MRgFUS is newly developed non-invasive procedure to reduce symptoms of uterine fi broids in an outpatient procedure. It combines MRI to visualize the body organs, plans and guides the treatment, and monitors the treatment outcome in real time, with high-intensity focused ultrasound waves, which destroy the tissue. Patients go home after the procedure and usually return to normal activities within a day or two. Unfortunately, it cannot be applied to every patient with uterine fi broids. The decision to perform the MRgFUS in patients with uterine fi broids is made according to the patient-selection guidelines in screening pelvic MRI. Imaging Findings: In screening pelvic MRI, several points must be evaluated carefully to meet the selection guidelines for MRgFUS in uterine fi broids. These include the fi ndings of fi broids itself, obstacles to sonication pathway and relation to adjacent structure. Conclusion: It must be requisite to know thoroughly the fi ndings in screening pelvic MRI to select suitable patients for MRgFUS in uterine fi broids.

Abdominal wall endometriosis: Imaging -pathologic correlation E. De Lama, L. Aja, R. Llatjos, J.A. Narvaez; Barcelona/ES Learning Objectives: To review the underlying pathologic changes that create the imaging appearances of abdominal wall endometriosis at US, CT and MRI.

To learn the imaging appearances of abdominal wall endometriomas and to illustrate the usefulness of imaging-guide preoperative biopsy. To review the main differential diagnosis. Background: Abdominal wall endometriosis occurs in up to 1% all women who have had cesarean deliveries, and may be diffi cult to diagnose. Procedure Details: We will review: 1) Pathologic changes in abdominal wall endometriomas. 2) US, CT and MRI fi ndings correlated with pathologic changes. 3) Usefulness of imaging-guide preoperative biopsy. In addition, differential diagnosis including nonneoplastic conditions, such as suture granuloma, ventral hernia, postsurgical hematoma or abscess, and neoplasms, such as a desmoid tumor, sarcoma, lymphoma, or metastasis will be reviewed.

Abdominal wall endometriomas are often non suspected clinically, but should be included in the differential diagnosis of a symptomatic mass in women who had cesarean deliveries. Pathologic characteristics of abdominal wall endometriomas (surrounding infl ammatory reaction and fi brosis, degraded blood products) explain most of the imaging features.

MR imaging of uterine cervical carcinoma: Optimization of local staging and evaluation after therapy S.M. Dias, A. Ferrão, C. Pina Vaz; Porto/PT Learning Objectives: To review the spectrum of magnetic resonance (MR) fi ndings clinically relevant for staging cervical carcinoma. To purpose technical strategies to optimize disease evaluation. To discuss clinical usefulness of MR for differentiation between recurrent disease and post-treatment complications. Background: Worldwide, cervical uterine cancer is second only to breast cancer as the most common malignancy in incidence and the third cause of death after breast and lung cancers in women. The Féderation Internationale de Gynécologie et Obstétrique (FIGO) classifi cation is the most commonly used staging system but it has recognized limitations that can be overcome with MR Imaging. Procedure Details: The authors present the spectrum of MR fi ndings useful for staging and differentiate treatment complications from recurrent disease. Technical strategies that can optimize local disease evaluation, such as intravaginal gel fi lling, are discussed. Pitfalls, advantages and limitations of MR when compared to other imaging methods, namely MDCT and Positron Emission Tomography (PET), are listed and illustrated comprehensively. Conclusion: Magnetic resonance imaging is a powerful tool in the work-up of cervical carcinoma. It optimizes selection of the most suitable therapeutic strategy for each patient, as it provides a more effi cient staging of the disease, evaluating accurately important prognostic factors as tumour volume and presence of lymphatic disease. It has also interest in detection of recurrent disease and in evaluation of treatment effi cacy and associated complications.

Diagnostic pitfalls in evaluating MR gynecological disorders S. Gispert, R. Domínguez, X. Merino, V. Pineda, S. Roche; Barcelona/ES (gisppi@yahoo.es)

Learning Objectives: To review the possible pitfalls in the evaluation of gynecological disorders by MR imaging. Background: MR imaging has an increasing role in evaluating female pelvis. The aim of the exhibit is to review the pitfalls in evaluating gynecological disorders. These pitfalls are roughly divided into physiological conditions that simulate organic lesions, benign conditions that simulate malignancy and malignant diseases that simulate benign conditions. According to the organ affected, we will show possible diagnostic pitfalls: uterus (pseudolesions related to uterine contraction that mimic leiomyoma or adenomyosis, adenomyosis that resembles uterine malignancies), ovary (appendicular mucocele or peritoneal cysts simulating ovarian tumors, ovarian atrophy simulating adenopathies), cervix (cervical carcinomas mimicking endometrial carcinomas), fallopian tube (hidrosalpinx resembling cystic masses), and vulva and vagina. Conclusion: It is important to know the wide variety of MR pitfalls in gynecological disorders in order to distinguish possible mimicking lesions from real organic lesions.

Purpose: To evaluate the capability of MRI in assessing pattern of recurrence threedimensional tumor volume and tumor response in patients with locally recurrent uterine cancer treated with concomitant chemo-radiation. Methods and Materials: Twenty-four women who had undergone radical hysterectomy and with locally recurrent uterine cancer were enrolled in our study. All patients underwent gynecologic examination and MRI to assess local recurrence. The recurrences were distinguished based on site: vagina, vaginal vault with or without pelvic wall extension, pelvic side wall. After diagnosis, the patients received concomitant chemo-radiation; then they underwent follow-up MRI 45days after the end of treatment and then periodically every six months. Pre-and post-treatment volumes were calculated by MRI with ellipsoid formula and compared determining tumor response: complete, partial, no change, progression of disease. Image analysis: MRI showed 15 patients with central pelvic recurrence, 9 with recurrence in the pelvic side wall. The mean pre-treatment 3D-volume was 34.96 mm 3 (range 0.29-302.49 mm 3 ). The mean post-treatment 3D-volume was 14.06 mm 3 (range 0-302.49 mm 3 ). 13 patients had complete response, 8 partial response, 2 no change, 1 progression of disease. Results: The site of response was associated to different prognosis; patients with recurrent tumor limited to vagina and vaginal vault showed better loco-regional control rates compared to patients with recurrence in the pelvic side wall. Recurrent 3D tumor volumes < 50 mm 3 had better diagnosis than larger tumor volumes. Furthermore, MRI is an accurate non invasive method of distinguishing tumor from fi brosis. Conclusion: MRI permitted a good evaluation of pelvic recurrences and tumor response following chemo-radiotherapy.

Optimization of T2-weighted fast spin-echo sequence for female pelvis at 3 T MR imager K. Fujimoto, T. Koyama, K. Tamai, N. Morisawa, Y. Nakamoto, K. Togashi; Kyoto/JP (kfb@kuhp.kyoto-u.ac.jp) Purpose: To optimize T2-weighted fast spin-echo sequence for female pelvis at 3 T MR imager. Methods and Materials: MRI were obtained at 3 T-imager (Siemens; Trio) using 8ch phased-array coil in eight healthy volunteers. All scans were performed with sagittal section with thickness of 3 mm, interslice gap of 0.9-1.5 mm, FOV of 260x195 mm without parallel imaging. Scans were performed: 1) before and after injection of anticholinergic agent (Buscopan), 2) with variable TR (8000, 6400, 4800, 3200), 3) with variable ETL (21, 17, 13) 4) with variable band-width (BW) (175, 205, 235, 260, 300) , and 5) with variable TE (79, 107-113, 148) with different types of RF pulse (low SAR vs normal mode). SAR of all scans was recorded. All images were qualitatively evaluated concerning artifacts, contrasts between B D E F A G

both inner, outer layer of the myometrium, the endometrium, and those between cervical epithelium and stroma. Quantitative measurement (SNR, CNR) of these structures was also performed. Results: Scans without Buscopan were considerably degraded by intestinal movements. Longer TR generally provided better SNR, although TR=8000 images in fi ve subjects were degraded by motion artifact from small intestine. TR=3200 were associated with high SAR (96-99%) and decreased CNR in the uterine corpus (p < 0.05). ETL=17 provided best images qualitatively. Although lower BW images provided better SNR, BW=175 images were associated with greater blurring. Qualitative evaluation did not reveal remarkable difference between BW=205-260, TE=79-113 images, although BW=300 and TE=148 images had decreased SNR. Low SAR RF pulse provided better SNR without statistical signifi cance. Conclusion: Our preliminary data suggest that the optimal parameters of T2WI at 3 T include TR=4800-6400, ETL=17, BW=205-260, TE=79-113 with RF pulse of low SAR type. Administration of Bustopan is essential.

Congenital mullerian anomalies: Three-dimensional ultrasound fi ndings M. Belloch Ramos, F. Raga Baixauli, P. Naranjo Romaguera, F. Bonilla Bartret, F. Bonilla Musoles, J. Palmero da Cruz; Valencia/ES Purpose: To asses the diagnostic value and the usefulness of three-dimensional (3D) ultrasound in detection of congenital mullerian anomalies, compared with other diagnostic methods (magnetic resonance, two-dimensional ultrasound, hysterosalpingography, laparoscopy and hysteroscopy). Mullerian anomalies are related to reproductive problems, but true incidence is unknown. 3D ultrasound represents a useful noninvasive tool to evaluate these anomalies.

A prospective study was undertaken from 1999 to 2005. A total of 10,352 women who went to a routine gynecological revision, were examined by 3D transvaginal ultrasound. All studies were stored in the hard disk and reviewed by three of the authors. Mullerian anomalies were classifi ed according to American Fertility Society (ASRM) classifi cation of 1988. Results: 517 mullerian duct anomalies were detected in 10,352 patients (4.99%). Arcuate (n=289, 59.8%) and septate (n=95, 18.3%) uteri were the most common malformations observed. The rest of anomalies observed were bicornuate (n=20, 3.8%), unicornuate (n=15, 2.9%) uteri and four DES-exposed uteri.

Conclusion: This study with noninvasive and cheap technique suggests that the prevalence of these anomalies is near 4.99%. The most frequent malformation was arcuate uterus considered nowadays like a normal variant. DES drug related uterus is rare today. improves diagnostic accuracy, with endometriotic cysts typically appearing with high signal intensity on T1-weighted images and demonstrating "shading" on T2-WI. Small implants and adhesions are not well evaluated radiologically; therefore, laparoscopy remains the standard of reference for diagnosis and staging. Although MR imaging is limited in its ability to depict small endometrial implants and adhesions, the advantages of MR imaging over laparoscopy include the ability to characterize endometriotic lesions and to evaluate extraperitoneal sites of involvement, contents of a pelvic mass, or lesions hidden by dense adhesions.

The roles of the two modalities are therefore complementary. Knowledge of the variety of MR imaging appearances of endometriosis and organ involvement is important for guiding a subsequent laparoscopic examination.

The monsters of the female pelvis: Pelvic teratomas revisited A. Ghiatas, D. Keramopoullos, C. Tsagari; Athens/GR (abraham@otenet.gr)

Learning Objectives: To illustrate the imaging fi ndings of teratomas on various imaging modalities. To discuss the appropriate selection of imaging modalities and techniques and how to avoid imaging interpretation pitfalls. Background: Pelvic teratomas is a frequent incidental fi nding in the course of imaging evaluation of the female pelvis for pathology unrelated to teratomas. Differential diagnosis of teratomas from other pelvic masses may be diffi cult unless the most optimal imaging modalities and techniques have been selected, which are able to demonstrate the specifi c features of this pathological entity. Procedure Details: 123 cases of pelvic masses were diagnosed as teratomas by CT, MRI or ultrasound, or a combination of them. All cases underwent surgery and pathology results were compared to the imaging fi ndings. Conclusion: In 119 cases, the imaging diagnosis of teratoma was in complete agreement with the surgical/pathology fi ndings, and in the remaining 4 cases, the diagnosis of teratoma was in agreement with the fi rst 3 diagnoses.

Factors 

Selective uterine arteriography of consecutive 60 patients who underwent UAE for symptomatic fi broids or adenomyosis were reviewed in regard to visualization of anastomosis with ovarian arteries. Factors including arterial spasm, uterine volume, location of lesion, birth history, and history of abdominal surgery were analyzed.

Results: Uteroovarian anastomosis was demonstrated in 25 of 60 patients (41.7%) and 34 of 120 uterine arteries (28.3%). There were 3 patients (5.0%) with visualization of anastomosis due to arterial spasm at the origin of the uterine artery, where the catheter was engaged. Anastomosis was seen in fi broids at subserosal (33.3%), intramural (35.7%), submucosal (43.8%), and adenomyosis (42.9%). Signifi cant difference was seen in the mean uterine volume: 547.1 cm 3 with anastomosis and 1024.0 cm 3 without anastomosis (p=0.027). Anastomosis was demonstrated in 44.4% of patients with multiple fi broids and 30.4% with solitary fi broid (odds ratio 1.82), 46.4% with multigravida and 31.0% with nullipara (odds ratio 1.92), and 44.4% in patients with a history of abdominal surgery and 35.9% without surgery (odds ratio 1.43).

Uteroovarinan anastomosis is often demonstrated during UAE irrespective of type and location of lesion. Arterial spasm by catheterization is a defi nite technical factor. Smaller uterine volume, multiple fi broids, and multigravida were considered as signifi cant factors of visualization of anastomosis.

Use of colour Doppler for early detection of hemorrhage in ultrasound guided renal biopsies K. Brabrand, A. Günther, P. Bache Marthinsen, A.E. Berstad; Oslo/ NO (knut.brabrand@rikshospitalet.no) Purpose: To evaluate the use of colour Doppler (CD) for early detection of hemorrhage after ultrasound guided renal biopsy.

A linear CD signal may be observed along the biopsy tract showing blood fl ow out of the kidney into the perirenal tissue immediately after withdrawing the needle indicating a post biopsy hemorrhage. To evaluate the incidence and duration of CD bleeding after renal biopsies, a prospective study was performed using an Acuson Seqouia with a 4V2 transducer (CD frequency 2.5 MHz, scale 0.12m/s). 78 patients were included. There were 90 biopsy procedures in 83 renal transplants and seven native kidneys with a total number of 243 biopsy needle passes. For each needle pass the presence and duration of CD bleeding were registered. If CD bleeding was seen, CD guided compression was applied. Results: CD bleeding was seen after 63 needle passes in 42 biopsy procedures. The incidence of CD bleeding increased with the number needle passes per procedure. The duration of CD bleeding exceeded four minutes in seven patients, of whom six developed a post biopsy hematoma. Eight of nine of the post biopsy hematomas (mean diameter 2.2 cm) were preceded by CD bleeding. CD guided compression was applied in 42 biopsy procedures. Conclusion: CD is useful in renal biopsies for early detection of post biopsy hemorrhage. The study shows that the duration of CD bleeding correlates with the severity of the bleeding. CD guided compression could possibly reduce the duration and volume of post biopsy bleeding.

Renal Learning Objectives: To familiarize the radiologist with the fi ndings of contrastenhanced ultrasonography (CEUS) of the commonest primary renal tumors. To present these fi ndings in the setting of an integrated diagnostic approach. Background: The high frequency of detection of renal lesions and the innovations in their treatment have increased the need for an accurate imaging diagnosis. This exhibit is based on the study of 68 renal tumors that were scanned before and after i.v. injection of a second-generation ultrasound contrast agent (SonoVue, Bracco). Representative CEUS images and the corresponding fi ndings of baseline and color Doppler US, CT, MR and DSA are displayed. Microscopic and macroscopic sections of the excised tumors confi rm these fi ndings and establish the fi nal diagnosis. Imaging Findings: Numerous cases of renal cell carcinomas (clear cell, papillary and cystic varieties), urothelial neoplasms, angiomyolipomas, oncocyttomas (typical and atypical) and a multilocular cystic nephroma are depicted. Several patterns of enhancement are described. The increased sensitivity of CEUS in outlining the pseudocapsule, small cystic areas and heterogeneity in the perfusion of renal tumors is demonstrated. The tortuous pathologic vessels at the periphery of the RCCs and the spoke-wheel pattern of the oncocyttoma are displayed. Challenging cases, such as isoechoic tumors that mimic normal variants and small lesions that are imperceptible on baseline US, are also included. Conclusion: Compared to fundamental US of renal tumors, CEUS may provide valuable additional information. CEUS fi ndings correlate well with those of other imaging methods and can contribute to an accurate diagnosis. Purpose: To investigate the perfusion characteristics of renal mass parenchyma and renal cortex in affected and normal kidney on 64-slice CT.

Totally 58 patients with renal mass were enrolled. 64slice spiral CT (Siemens Somatom Sensation 64) was used for renal perfusion scan that began with a contrast bolus injection of 50 ml (370 mgI/ml) at a rate of 5 ml/s. Surgical and pathological outcomes were collected for comparison. Perfusion characteristics, including blood fl ow (BF), blood volume (BV) and permeability (PM) of renal mass parenchyma and renal cortex in affected and normal kidney were calculated from 'Siemens Body PCT (VB20B)' software.

Results: Renal clear cell carcinoma (RCCC), renal pelvic transitional cell carcinoma (RPTCC) and renal angiomyolipoma (RAML) was pathologically confi rmed in 30, 5 and 11 of 58 subjects, respectively, while the remaining 12 subjects were with renal simple cyst (RSC). Technical failures were experienced in 1 (1.7%) patients. Perfusion parameters of tumor parenchyma were measured as follow: RCCC: BF=92.9±26.6, BV=177.0±55.3, PM=110.4±32.9; RPTCC: BF=46.5±22.1, BV=79.7±32.3, PM=63.3±19.4; RAML: BF=50.7±17.6, BV=113.2±47.0, Perme-ability=60.1±23.9; RSC: BF=7.1±6.1, BV=18.0±10.8, Permeability=16.0±8.8. In all groups, perfusion parameters showed signifi cant differences (P < 0.01) between mass parenchyma and renal cortex in normal kidney, while there were no signifi cant difference (P> 0.05) in perfusion parameters between renal cortex in affected and normal kidney. There were signifi cant differences (P < 0.05) in perfusion parameters between parenchyma in any two kinds of renal masses, except for RPTCC and RAML (P> 0.05). Conclusion: These four kinds of renal masses all have decreased perfusion characteristics. Perfusion imaging with MSCT has potential clinical application value in differential diagnosis of renal mass.

Vascular complications after renal transplantation: US fi ndings I. de la Pedraja, N. Gomez, J. Hernandez, M. Ciudad, E. Vaño; Madrid/ES Learning Objectives: 1) To illustrate the different types of vascular complications after renal transplantation, with emphasis on their characteristic chronology. 2) To be familiar with the ultrasound fi ndings that allow us to diagnose vascular complications in renal allografts. Background: Renal transplantation is the treatment of choice for severe endstage renal failure. Because of this, it is very important for the common radiologist to know enough about the diagnosis and management of renal grafts complications, especially the vascular ones, which are a very frequent and severe reason of early graft failure and reject, and a common request of diagnostic procedures in the emergency room. Imaging Findings: We illustrate some examples of the different types of vascular complications associated with renal transplants, including graft artery and recipient iliac arterial system stenoses, arterial and venous thromboses, focal and diffuse infarcts, pseudoaneurysms and arteriovenous fi stulas. Some examples not only of single kidney grafts complications but of "En Bloc" transplants complications are presented. We also discuss the imaging features of vascular complications in grayscale sonography and Doppler sonography, and, in some cases, the appearance of the subsequent fi ndings in MRI and angiography. In addition, we emphasize the characteristic chronology of each vascular complication. Conclusion: Although angiography is still the "gold standard" in the diagnosis of vascular complications in renal transplantation, ultrasound is usually the fi rst step in the diagnostic procedure, and is a valuable technicque that allow the radiologists to make an early diagnosis of them.

Correlation of hemodialysis duration with enthesal site changes of hemodialysis patients by lower limb ultrasonographic examination U. Kerimoglu, M. Hayran, F.B. Ergen, A. Kirkpantur; Ankara/TR (ulku09@yahoo.com)

Purpose: To evaluate the enthesal site changes of the lower limb of patients on hemodialysis utilizing Glosgow Ultrasound Enthesitis Scoring System, and to assess the correlation between the duration of hemodialysis and the score of patients. Methods and Materials: Forty-nine patients who are on hemodialysis for at least 2 years were included in the study. The patients were subgrouped according to the duration of hemodialysis; 2 to 5 years (group 1, n=14), 5 to 10 years (group 2, n=15), 10 to 20 years (group 3, n=12) and more than 20 years (group 4, n=8). For each patient, the total score of GUESS, the mean score of GUESS for each group, total score for enthesophyte and erosion were correlated with the duration of hemodialysis.

The mean of the total GUESS scores (8.8±3.0, 13.5±3.0, 17.9±4.5, 23.4±4.6 for groups 1-4, respectively) increased signifi cantly among gropus (p < 0.001, Jonckheere-Terpstra test). There was statistically signifi cant correlation between the duration of hemodialysis and total GUESS scores (p < 0.001, r s =0.81), especially for men. Signifi cant correlation was seen between the duration of hemodialysis and total enthesophyte and erosion scores (p < 0.001). If severe enthesitis was to be defi ned as a total GUESS score of more than 18, a receiveroperating characteristic curve analysis reveals a cut-off point of 10 years (with 83% sensitivity and 93% specifi city) that results in severe damage (area under the ROC B D E F A G

curve: 0.92, 95% confi dence limits: 0.83-1.00). Conclusion: Kidney transplantation performed as early as possible, especially before 10 years, would prevent severe enthesitis.

Laparoscopic cryoablation (LC) of small renal cell carcinoma (RCC): Mediumterm outcome after 5-year magnetic resonance (MR) imaging follow-up G. Cardone, C. Iabichino, A. Cestari, P. Mangili, G. Guazzoni, G. Balconi;

Purpose: This study aims to determine the safety and effi cacy of LC in the management of small RCC, and to assess its medium-term outcome after 5-year MR imaging follow-up. Methods and Materials: Seventy-one patients underwent LC for a total of 75 treated tumors. All treatments were administered under laparoscopic US guidance. Patients were followed-up clinically, biochemically, and by MR imaging 24 hours after surgery, and subsequently at 1, 3, 6, 12, 18, 24, 36, 48, and 60 months. All MR examinations were performed with a 1.5 T MR system using GRE T1w, TSE T2w sequences and ce dynamic GRE FS-T1w sequence. Results: Cryolesions decreased in size by an average of 38% at 1 month, 46% at 3 months, 64% at 6 months and 80% at 12 months following LC. Post-procedural MR ce-T1w images showed complete ischemia of all cryolesions. Follow-up revealed no evidence of local or distant recurrence in 64/71 patients (90%). One patient showed local recurrence at 12 months; 3 patients demonstrated 1 metachronous nodule in the same kidney at 12, 18, and 60 months, respectively; 2 patients showed 1 metachronous nodule in the controlateral kidney at 18 and 24 months,respectively; 2 patients showed pancreatic metastatic nodules at 6 and 12 months. In 21 cases, a small perilesional haematoma was evident at 1 and 3 months after surgery. Conclusion: Our 5-year medium-term experience suggests that LC is a safe, well tolerated, and minimally invasive therapy for small RCC, and MR is an effective imaging technique in the follow-up of RCC treated with LC.

Primary renal lymphoma P. Filis, E. Protopapa, A. Gyftopoulos, G. Delimpasis, E. Sammouti, E. Seferos, A. Fousteris; Athens/GR Learning Objectives: 1. To evaluate the role of multislice CT and MRI in primary renal lymphoma. 2. To become familiar with both typical and atypical manifestations of primary renal lymphoma. 3. To review the basic concepts of primary renal lymphoma. Background: Renal lymphoma is most often seen in conjunction with multisystemic, disseminated lymphoma. Reports on primary renal lymphoma are scarce in the urological literature, the most part of them being secondary on a lymphomatous infi ltration of the kidneys. Primary renal lymphoma (PRL) as a clinical entity is not undisputed because the kidneys do not contain lymphatic tissue. Multislice CT is the most sensitive and comprehensive examination for evaluation of the kidneys in patients with suspected renal lymphoma. In particular, it improves detection and characterisation of lymphomatous renal involvement by optimising contrast dynamics and data acquisition and is the current modality of choice for accurate staging of lymphoma. We report the case of three patients with an incidental mass on the kidney; their diagnosis and management are discussed. A literature review on currently recommended diagnostic practices will be presented. Typical and atypical CT patterns which provide a diagnostic challenge will be discussed. Procedure Details: CT scans were performed on a multislice CT. Magnetic resonance imaging was performed on a 1.5 Tesla scanner. Conclusion: Multislice CT is useful in the evaluation of patients with suspected renal lymphoma; familiarity with the spectrum of fi ndings in renal lymphoma is important for accurate diagnosis and, when necessary, the recommendation of imaging guided percutaneous biopsy.

CT-guided biopsies in patients with renal transplant and suspicion of rejection C. Kalogeropoulou, P. Kraniotis, P. Zampakis, A. Tsamandas, T. Petsas; Patras/GR Purpose: Renal biopsy is a necessary step in the diagnostic work-up of patients with a renal allograft, presenting with renal dysfunction and suspicion of rejection. We evaluated the safety and effi cacy of CT-guided core biopsies in renal transplant patients with deteriorating renal function and clinical suspicion of transplant rejection. Methods and Materials: During the last 2 years, we performed 20 CT-guided biopsies in 17 patients (14 male), mean age 37 (range 21-57) years. The indications for biopsy included: increased serum creatinine 70% (14/20), albuminuria 15% (3/20), delayed renal function 10% (2/20) and progressive functional decline 5% (1/20). The patients underwent pelvic CT and optimal site for tissue sampling was selected. All biopsies were performed using a 20G automated core biopsy needle. One pass per patient was performed. Results: An average of 1 tissue core per biopsy was obtained. Adequate tissue sample (≥3 glomeruli per specimen) was acquired in all cases. Histological examination revealed tubular atrophy 5% (1/20), acute rejection 55% (11/20), chronic nephropathy 15% (3/20), acute tubular necrosis 10% (2/20), focal segmental tubular sclerosis 5% (1/20) and interstitial fi brosis 10% (2/20). Technical success reached 100%. There were no major post-procedural complications. Conclusion: Core biopsy of the transplant kidney is an essential diagnostic tool for patients with dysfunctional renal transplant and suspicion of rejection. The procedure has a high diagnostic yield, infl uencing in a critical way any further management. CT-guidance offers the advantage of better targeting the kidney allograft in the pelvis, avoiding superimposed bowel loops, and hence decreasing the complication rate.

Measurement of glomerular fi ltration rate and renal blood fl ow using dynamic contrast- 

Comparison of sonoelastography guided biopsy with systematic biopsy: Impact on prostate cancer detection L. Pallwein, F. Aigner, E. Pallwein, V. Fischbach, J. Gradl, F. Frauscher; Innsbruck/ AT (leo.pallwein@uibk.ac.at) Purpose: We performed a prospective study to determine whether a limited biopsy approach with sonoelastography (SE) targeted biopsy of the prostate would detect cancer as well as gray scale US guided systematic biopsy with a larger number of biopsy cores.

We examined 230 men (mean age: 62.3) with a total PSA of 1.25 ng/ml or greater. First investigator performed 5 or fewer SE targeted biopsies into suspicious (stiffer) regions in the peripheral zone. Hard lesions were considered as malignant. Subsequently, another examiner performed 10 systematic prostate biopsies. The cancer detection rates of the 2 techniques were compared. Results: Cancer was detected in 81 of the 230 patients (35%), including 68 (30%) by SE targeted biopsy and in 58 (25%) by systematic biopsy. The overall cancer detection rate by patient was not signifi cantly different for SE targeted and systematic biopsy (p = 0.132). The detection rate for SE targeted biopsy cores (12.7% or 135 of 1,109 cores) was signifi cantly better than for systematic biopsy cores (5.6% or 130 of 2,300 cores, p < 0.001). SE targeted biopsy in a patient with cancer was 2.9-fold more likely to detect prostate cancer than systematic biopsy. Conclusion: Sonoelastography targeted biopsy detected as many cancers as systematic biopsy with fewer than half the number of biopsy cores. Although an increase in cancer detection was achieved by combining targeted and systematic techniques in this screening population, Sonoelastography targeted biopsy alone is a reasonable approach for decreasing the number of biopsy cores.

Transrectal ultrasound ( Background: Since TRUS is the most effi cient way to detect prostate cancer (PrCa), this e-book aims to teach the TRUS procedure in detection and staging of PrCa and correlate it with the histological fi ndings emphasizing the use and effectiveness of USCA and local anesthesia prior to biopsy sampling. Procedure Details: This medical e-book is a multimedia DVD Rom-based teaching fi le featuring 2500 US prostate images, 150 US video demonstrations, 400 video cases presenting clinical data and detailed description of TRUS techniques, chapters on prostate anatomy, TRUS technique for the detection and staging of PrCa (based on over 10,000 cases), color Doppler, and the technique of USguided biopsies. The proper TRUS technique is demonstrated step by step. Its educational role is based on video cases and double video presentations. The latter consists of a simultaneous presentation of the real-time ultrasound exam and the examiner's technique. A database is included in aiding the user to reach the correct diagnosis and to compare his sonographic image to histologically proven images of the database. Conclusion: User-friendly DVD Rom-based teaching fi le on the prostate with chapters on anatomy, pathology, ultrasound physics, sonographic appearance of the normal prostate, TRUS morphology, detection and staging of PrCa, local anesthesia, USCA and comparative database. Learning Objectives: Review the sonographic fi ndings of non-neoplastic pathologic processes involving the extratesticular structures in the adult patient. Background: The scrotum is a fi bromuscular sac divided by a median raphe. It contains the testis, epididymis, spermatic cord, and associated fascial coverings. These structures can be affected by several pathologies including congenital, infl ammatory and neoplastic.Ultrasonography is the primary modality for imaging the scrotum. It should be performed with the highest frequency transducer that provides adequate penetration. Intratesticular versus extratesticular pathologic conditions can be differentiated with a high sensitivity. Imaging Findings: In this pictorial review, we describe and illustrate cases selected from our radiology department fi les of non-neoplastic extratesticular disorders in adults. The following pathologic entities are included: (1) Fluid collections: hydroceles, hematoceles and pioceles; (2) Epididymis: acute and chronic epididymitis, cysts, spermatoceles and granulomas; (3) Spermatic chord: hematomas, torsion, lipomatous infi ltration and varicocele; (4) Paratesticular masses: inguinal hernias.

The information obtained with gray-scale and color Doppler ultrasonography is suffi cient to enable diagnosis in most cases of non-neoplastic extratesticular disorders in the adult patient. Because physical examination usually lacks specifi city for scrotal lesions, the radiologist should be in the position of making an early and correct diagnosis in order to direct further work-up and avoid severe complications.

Pre-treatment evaluation of prostate cancer with MRI and threedimensional 1H-magnetic resonance spectroscopy: Our experience S. Giusti, M. Lazzereschi, F. Francesca, A. Tognetti, D. Caramella, C. Bartolozzi; Pisa/IT Purpose: Our aim was to assess the accuracy of 1H-magnetic resonance spectroscopy (MRS) in patients with high prostate-specifi c antigen (PSA) levels and biopsy proven prostate carcinoma, candidate to radical prostatectomy. Methods and Materials: Twenty-one patients underwent MRI and MRS for the evaluation of tumor location, local extent and aggressiveness of prostate cancer. Our imaging protocol included axial, coronal and sagittal T2wi FSE sequences and an axial T1wi FSE sequence. For MRS, we used 3D chemical shift imaging (CSI) spin-echo sequence. We divided the prostatic gland into six sextants and sensitivity, specifi city and accuracy of biopsy, MRI, MRS, MRI+MRS were calculated with pathological correlation. Conclusion: Combined MRI and 3D 1H MRS of the prostate have a diagnostic advantage in tumor location over MRI alone and over biopsy alone. In particular, a negative result at 3D 1H MRS is able to exclude the presence of cancer with high probability. We are further investigating whether there is a correlation between high Gleason score and MRS sensitivity.

The 

All studies were performed with a 1.5 T superconducting system. Twenty-nine prostatic cancers (> 10 mm) in 34 patients were included. Radical prostatectomy was performed in all patients within 2 months after MRI. T2weighted image with fat saturation and ADC map by each method were obtained. Trace ADC map of the normal prostatic tissue (peripheral zone: PZ and inner gland: IG) and prostatic cancers were evaluated by each method. Results: Normal PZ ADC was 1.763 + 0.205 (×10 -3 mm 2 /s) by SS-EPI, 1.496 + 0.939 (×10 -3 mm 2 /s) by LSDI. Normal IG ADC was 1.382 + 0.223 (×10 -3 mm 2 /s) by SS-EPI, 1.258 + 0.866 (×10 -3 mm 2 /s) by LSDI. There was signifi cant difference between SS-EPI and LSDI by Student's t-test (p < 0.05). In three normal PZs, susceptibility artifacts arose from the air-fi lled rectum. Prostatic cancer ADC was 0.951 + 0.256 (×10 -3 mm 2 /s) by SS-EPI, and 0.783 + 0.226 (×10 -3 mm 2 /s) by LSDI. Two prostatic cancer ADC by SS-EPI were not calculated, because of susceptibility artifact arising from the air-fi lled rectum. All prostatic cancer ADC by LSDI were calculated without susceptibility artifact arising from the air-fi lled rectum. Conclusion: There was signifi cant difference between ADC by SS-EPI and by LSDI. ADC by LSDI in both prostatic cancer and normal prostate were inherently insensitive to susceptibility artifacts. B D E F A G

Intra-and extra-testicular cystic lesions: US and MRI fi ndings R. Prada González, G. Tardáguila de la Fuente, J. Aguilar Arjona, E. Santos Armentia, C. Rivas, G. Fernández; Vigo/ES (rachelpg@terra.es)

Learning Objectives: 1) To review the clinical, pathological and imaging manifestations of scrotal cystic lesions. 2) To demonstrate the roles of US and MRI in the diagnosis of scrotal cystic masses. Background: When studying a scrotal mass, the two most important questions to be answered are whether the lesion is intra or extra-testicular, and whether it is cystic or solid. Extratesticular masses, both cystic and solid, are usually benign. However, when the mass is intratesticular, the prognosis of cystic and solid masses is quite different. Intratesticular solid lesions should be considered malignant, whereas intratesticular cystic lesions are most likely benign. Therefore, although intratesticular cystic masses are rare, its recognition is important, in order to avoid unnecessary surgical intervention. Procedure Details: We study clinical, pathological and imaging manifestations of scrotal cystic masses. Intratesticular cystic lesions include simple cysts, tunica albuginea cysts, tubular ectasia of the rete testis, testicular epidermoid cysts (misnamed cyst because it is solid lesion), abscess and, in some cases, infarctions and teratomas. Extratesticular cystic lesions are hydrocele, hematocele, varicocele, spermatocele, papillary cystadenoma, spermatic cord cyst and hernia. US is the fi rst choice modality for studying these lesions. MRI is seldom needed, but provides useful information when US results are inconclusive.

In order to make a correct diagnosis and to prevent unnecessary surgical intervention, it is of the utmost importance to recognize imaging features of intra-and extra-testicular cystic masses. Although ultrasound is the primary imaging modality for researching testicular lesions, MRI proves to be an useful tool when the results of US are unclear.

Ultrasound appearances of intra-testicular tumours: Gray-scale imaging features with histologic correlation to allow prediction of tissue type T. 

Diagnostic value of PWI in prostate cancer and benign prostatic hyperplasia X. Zhao, R. Bai; Tianjin/CN (xin-cheng@163.com)

Purpose: To evaluate the diagnosis and differential diagnosis value of PWI for prostate cancer (PCa) and benign prostatic hyperplasia (BPH). Methods and Materials: Fifty-three cases were divided into three groups: Group 1 included 23 cases of PCa, group 2 included 22 BPH cases, 8 cases were enrolled in group 3 as normal control. All subjects were examined with 1.5 T Twin-Speed Infi nity with Excite II (Signa; GE Medical System). The sequence of PWI was axial single shot gradient recalled echo echoplanar imaging T 2 * WI. Then the SI-T curve and PWI parameters were obtained. To compare the difference of perfusion-related parameters including rNE (relative negative enhancement integral), rMTE (relative mean time to enhance) and rMSD (relative maximum slope of decrease) among three groups. Results: In the peripheral zone (PZ), the value of rNEI of PCa was higher than that of BPH (t=11.64, P < 0.001) and normal (t=11.79, P < 0.001). The value of rMTE of PCa was lower than that of BPH (t=3.50, P=0.002) and normal (t=3.78, P=0.001).

In the central zone (CZ), the value of rNEI of PCa was higher than BPH (t=6.99, P < 0.001) and normal (t=10.32, P < 0.001). According to ROC, the rNEI had the best differential diagnosis effi ciency. The optimal threshold was calculated as 6.44 with a sensitivity of 91.3% and a speciality of 89.2% for differentiating PCa. Conclusion: rNEI is an effective parameter to differentiate PCa from BPH.

Comparison Purpose: The histologic grade of a prostate needle-core biopsy specimen can determine whether a patient with prostate cancer is a candidate for radical prostatectomy or another treatment. The aim of this study was to illustrate the concordance of Gleason score between biopsy and radical prostatectomy. Methods and Materials: We retrospectively reviewed clinical and pathological data of 51 patients who underwent TRUS biopsy and radical prostatectomy between 2004 and 2005. Of the included patients, 9 men had undergone a nonextended sextant biopsy scheme (type A), 33 patients a 6-10 extended scheme (type B), and 9 patients a 10-14 extended biopsy (type C). Clinical parameters were available and sonography fi ndings were included. Biopsy and prostatectomy specimens were reviewed by the same staff. The rate of grading concordance and the effect of different biopsy schemes (A,B,C) on the concordance rate was determined. Results: The TRUS fi ndings and the number of cores affected were similar in the 3 groups (p < 0.011; p < 0.045) according to the Jonckheere-Terpstra test. The concordance between prostate biopsy and radical prostatectomy Vacurg score was 2/9 cases [A scheme (22.2%)], 22/33 cases [B (66.7%)] and 8/9 cases [C (88.9%)] (z test -3.793; p=0.000). Biopsy understaging was found in 7/9 cases (77.8%); 11/ 35 cases (33.3%) and 1/9 cases (11.1%), respectively, (z test -3.55) B D E F A G

(z test -3.954; p=0.000). Primary Gleason pattern was predicted exactly by biopsy in 3/8 cases (37.5%); 26/35 cases (74.3%) and 9/9 cases (100%), respectively (z test -3.557; p=0.000). Conclusion: Extended needle biopsy signifi cantly increases the accuracy of biopsy Gleason score for assessing fi nal prostate cancer grade. 

Correlating radiological and histopathological staging for prostate cancer in a general NHS setting: Do fi ndings live up to national standards? A. Raza, S. Higgins, R. Mason, N. Ryley; Torquay/UK Purpose: Preoperative MRI staging of prostate cancer is more accurate with higher strength magnets and endorectal coils; however, these are still not widely available in all UK hospitals. We assessed the degree of accuracy using a 1 Tesla magnet and a pelvic array coil (a common setup throughout the UK). All patients subsequently underwent radical prostatectomy, and the results of preoperative MRI staging were compared with histological fi ndings. Methods and Materials: Thirty-three patients were identifi ed by the urology records from August 2003 to 2005. The imaging was performed with 1 Tesla magnet without endorectal coils. All patients underwent radical prostatectomy. Case notes were retrieved and reviewed in detail along with histopathology. MRI studies were reviewed in a blinded fashion. Results: 26/33 patients had an MRI done (78.78%). 12/26 patients had MRI and histopathological concordance (46.15%). 14/26 patients were non-concordant with histopathological results (53.84%). Out of these 14 patients, 9 were false -ve and 5 were false +ve.

The Royal College of Radiologists (UK) guidelines for reporting accuracy at MRI range from 66 to 83%. This study using a 1 Tesla magnet without access to endorectal coil had poor staging accuracy and possibly refl ects the current situation in many UK hospitals. Access to endorectal coils or higher strength magnets is a major factor in increasing staging accuracy. This study arguably reports accuracy fi gures more representative of average NHS radiology services, and therefore raises important concerns about the validity of existing national standards and guidelines. The protocol consisted in fat-sat fast spin-echo T2 sequences, Gd-enhanced dynamic study with 3D FLASH sequences (1 before and 5 after gadoteridol 0.1 mmol/kg, temporal resolution 35 s), T1-weighted fat-sat fast spin-echo sequence and 3D CSI proton spectroscopy. Dynamic sequences were post-processed with image subtraction (enhanced minus unhenanced) and intensity/time curves for targeted regions of interest. Proton spectroscopy data were evaluated generating 1H spectra voxel-by-voxel, choline maps and choline/citrate ratio maps. Conclusion: A complete protocol can be performed in less than 30 minutes, including morphologic images, dynamic study and 1H-MRS. 

Prostate cancer: MR spectroscopy after radiation therapy -initial experience J. Rembak-Szynkiewicz, B. Bobek-Billewicz, W. Senczenko; Gliwice/PL (remszyn@wp.pl)

Purpose: To evaluate prostate MR spectroscopy after radiation therapy in patients with complete biochemical remission. Methods and Materials: Combined endorectal MR imaging and MR spectroscopy in 12 patients after radiation therapy of prostate cancer without biochemical signs for recurrent disease was performed. Patients with the prostate-specifi c antigen (PSA) level below 1 ng/ml were chosen. No increase of PSA rate within 3 months post examination was observed. 8/12 patients underwent external-beam radiation therapy, 3/12 patients underwent external-beam radiation therapy and prostate brachytherapy prior to our study. The mean radiation dose was 74Gy. MR spectroscopy (Medrad endocoil) was performed with 1.5T Siemens Avanto MR scanner. Siemens software was used for three-dimensional (TE=120 ms) 1 H-MR spectroscopic data acquisition and processing. The metabolite (Cho, Cr and Cit) peaks were considered and (Cho+Cr)/Cit was calculated. Results: Voxels with a (Cho+Cr)/Cit ratio of 1 or more were found in 4/12 patients in prostate peripheral zone. Voxels with value of a (Cho+Cr)/Cit ratio of 1 and less in prostate peripheral zone were found in 8/12 patients. Voxels with a (Cho+Cr)/Cit ratio of 1 or more were found in 9/12 patients in prostate central zone; furthermore, in 3/12 patients this ratio was equal or below 1 in prostate central zone.

Conclusion: Increased value of (Cho+Cr)/Cit ratio may be found (appear) in patients with complete biochemical remission even after several months post radiation therapy. That can represent a presence of neoplasmatic cells in prostate months after radiation therapy despite lack of biochemical and clinical evidences of disease.

Where is the pelvic sidewall? An anatomical depiction with radiological and surgical correlates T.D. Suaris, A. Sahdev, R. Reznek, A. Rockall; London/UK (tamarasuaris@hotmail.com)

Learning Objectives: To describe the anatomy of the surgical pelvic sidewall with annotated schematic drawings and CT and MRI correlates. To illustrate with video clip the laparascopic dissection of the pelvic sidewall (PSW) with cadaveric dissection of the pelvic sidewall, and compare the radiological and laparascopic views.

To demonstrate with imaging the alteration of anatomical borders with reference to: primary invasive disease, post radiotherapy changes, post surgical changes, recurrent disease.

To demonstrate examples of pelvic malignancies invading the PSW to varying degrees. Background: The assessment and staging of the spread of malignancy within the pelvis require detailed knowledge of the structures and anatomy of the pelvis. However, the exact delineation of the PSW can be diffi cult on cross-sectional imaging. Pelvic exenteration is a salvage procedure performed for centrally recurrent gynaecological cancers. The procedure involves en bloc resection of all pelvic structures. The surgery is complex and associated with high-rates of complication. PSW involvement in these patients is a contraindication to radical or exenterative surgery. Imaging Findings: The surgical approach to the pelvic sidewall is based on layers from deep to lateral. Understanding this approach, CT and MRI images of the PSW will be annotated to revise the layers of the pelvic wall. Imaging will demonstrate the involvement of ureters, neurovascular structures, obturator nerves and vessels and obturator internus and piriformis muscles.

The importance of understanding the complex anatomy of the pelvis on cross-sectional imaging allows correct interpretation of pelvic pathology. Average equivalent doses/operation for the surgeon (PCNL) for a crystalline lens and hands: 74µSv and 222 µSv accordingly.

The average effective dose level/operation (PCNL) is 5.4 times more than of retrograde operations. The greatest level of doses is measured on the eye which is located more closely to the X-ray source. The right hand dose level of the surgeon is 1.5 and left hand is 2.7 times more than those of the assistant (PCNL).

The 

descended testes, herniated bowel, and varicoceles. Uncommon masses include liposarcomas, testicular tumors, lymphoma, and neurofi brosarcomas. Familiarity with the normal anatomy as well as the imaging characteristics of these masses is essential for correct image interpretation. Imaging Findings: Via CT and MRI images, this exhibit will review the embryology, male and female anatomy of the normal structures associated with the inguinal canal. We will also present the imaging features and the clinico-pathological background of common and uncommon masses located in the inguinal canal. Conclusion: On completion of this exhibit, the attendee will become familiar with the anatomy, pathology, embryology and imaging characteristics of the common and uncommon masses in the inguinal canal. Learning Objectives: 1. To illustrate the spectrum of imaging features of tuberculosis of the genitourinary tract. 2. To review the differential diagnosis of genitourinary tuberculosis. Background: Tuberculosis is the most common cause of mortality from infectious diseases worldwide. The prevalence of this infection has increased over the past decade in most developed countries and extrapulmonary tuberculosis represents a a progressively greater proportion of the new cases. Genitourinary tuberculosis is an important but uncommon form of TB, although it is the second most common form of extrapulmonary tuberculosis. Diagnosis is often diffi cult and delayed because TB can mimic many other diseases. Radiologic examinations are very useful to determine the presence of tuberculosis and to monitor de therapeutic effi cacy. Imaging Findings: This pictorial review illustrates the radiological features of genitourinary tuberculosis. It shows intravenous urography, retrograde pyelography, US, CT and MR images of differents stages of tuberculosis affecting the kidney, ureter, bladder and genital tract. Conclusion: Diagnosis of genitourinary tuberculosis is often diffi cult and delayed, as there are many pathologic conditions that can mimic this entity. Although defi nitive diagnosis is established by cultive or histologic examination, radiologic examinations are useful in suggesting the presence of the disease and it is important for the radiologist to be familiarized with the fi ndings of genitourinary TB.

Demonstration of the anatomy of the right adrenal vein with multidetector row CT T. Matsuura, K. Takase, T. Yamada, A. Sato, S. Takahashi; Sendai/JP Purpose: Adrenal venous sampling is essential for an accurate diagnosis of primary aldosteronism. Information about the anatomy of the right adrenal vein (RAV) obtained by CT would be useful in planning adrenal venous sampling. The purpose of our study is to determine how frequently the RAV could be identifi ed on MDCT and what spectrum of anatomic variations was seen among the RAV. Methods and Materials: Post-contrast MDCT were retrospectively reviewed in104 patients. CT scan was performed with a MDCT (8-row) scanner (1 mm collima-tion, pitch 7). Contrast material (100 mL, 300 mgI/mL) was injected at a rate of 3.5 mL/sec. Axial slices of 1-mm thickness were evaluated. The following points were evaluated regarding the RAV: The rate of visualization, the relationship to an accessory hepatic vein, the anatomy, including the location of the orifi ce in relation to the IVC, direction from the IVC, length and diameter. Results: The RAV was detected in 79 (76%) of 104 patients. The RAV formed a common trunk with an accessory hepatic vein in 8%. The RAV joined in the right posterior wall of the IVC in 97% and in the left posterior in 3%. The direction of the RAV from the IVC was posterior and rightward in 77%, posterior and leftward in 23%, caudal in 89% and cranial in 11%. The length and diameter averaged 3.8 mm and 1.7 mm, respectively. Conclusion: MDCT enabled identifying the RAV and delineating its anatomy, including the position and relationship to the IVC in most patients. Learning Objectives: To illustrate the use of additional series following unenhanced CT performed for suspected renal colic, to both improve diagnostic certainty and confi rm other important diagnoses. Background: Unenhanced CT is widely accepted as the primary investigation for suspected renal colic. Renal cell carcinoma and transitional cell carcinoma may both present with loin pain or haematuria and non-urological pathology may mimic renal colic. In a cohort of cases from our institution, we found that additional series were required in 12% of cases to improve diagnostic certainty. To our knowledge, a review of this subject has not been published in the literature. Imaging Findings: From our cohort of unenhanced CT scans, we illustrate how additional series clarify an uncertain diagnosis. Prone scanning can distinguish a bladder calculus from a calculus at the uretero-vesical junction. CT urography may differentiate a phlebolith from a ureteric calculus. Parenchymal contrast enhancement can confi rm the diagnosis of renal or urothelial malignancy as well as characterize incidental complex renal cysts. Contrast enhancement may also provide additional important diagnostic information in a range of non-urological pathologies. Conclusion: Additional series were required in 12% of cases following unenhanced CT for suspected renal colic to improve diagnostic certainty and confi rm other important diagnoses such as urological malignancy and non-urological pathology, both of which can mimic the presentation of renal colic.

Genitourinary tract disease in the emergency room: A pictorial review D. Learning Objectives: To review imaging fi ndings of genitourinary pathology in the emergency room in a third level hospital according to available diagnostic imaging methods (ultrasound, computed tomography, intravenous urography and interventional radiology). Background: Patients with genitourinary disease represent an important volume of the total number of consultations in emergency services and, therefore, in the daily work of the radiologist on call. The more frequent reasons for consultation in these patients include lumbar or genital pain, febrile syndrome, hematuria, anury or oligoanury, acute renal insuffi ciency and trauma, among others. During the last 18 months (January 2005-June 2006), over 6500 emergency sonography and 4300 CT exams were performed at our center. Genitourinary pathology was involved in approximately 20% of these examinations, either suspected or not. The spectrum of fi ndings in these conditions has been reviewed during this period. Imaging Findings: The detected pathology was classifi ed, fundamentally, in infectious/infl ammatory conditions, obstructive disorders, trauma and complications associated with renal transplantation or other interventional or surgical procedures. Imaging techniques were mainly ultrasonography and CT. Intravenous urography was less frequently used. Interventional radiology had also a therapeutic role in selected cases.

The radiologist must be aware of the wide variety and high prevalence of emergency genitourinary pathology and its imaging fi ndings according to the available imaging techniques. He also must be aware of the possibilities of interventional radiology as a therapeutic approach in selected patients. (100%) with HR-T2WI. The overall accuracy was (74%) by T2WI MRI and (79%) by HR-T2WI (p=0.001). As regards to lymph node staging, T2WI and HR-T2WI had equal accuracy (sensitivity 85.7%, specifi city 97% and overall accuracy 93%). Conclusion: HR-T2WI is only slightly more accurate than T2WI in overall local staging (p=0.003) and has equal accuracy in lymph node staging. In invasive stages, however, HR-T2WI is signifi cantly more accurate (p < 0.001).

Value of multidetector CT in preoperative assessment of ureteropelvic junction obstruction A. Mishra, J.N. Bhaktarahalli; New Dehli/ IN (dranujmish@yahoo.com) Learning Objectives: To assess the role of multidetector computed tomography (MDCT) in the evaluation of crossing renal vessel (CRV) as the cause for ureteropelvic junction (UPJ) obstruction and to describe its technique. To outline its advantages over color Doppler imaging and digital subtraction angiography (DSA). Background: An accessory renal artery crosses the UPJ in only 11-39% of patients with UPJ obstruction. CRV are usually located anterior to the UPJ and its preoperative identifi cation is of utmost signifi cance as it changes the surgical management.

In this exhibit, we describe the usefulness of MDCT and its advantages over color Doppler imaging and catheter angiography. Procedure Details: MDCT was done on 16-row MDCT scanner. A plain scan was performed with a 10 mm. collimation through the kidneys to identify the renal poles and aortic bifurcation. 40 mg of injection Furosemide was injected intravenously as a diuretic. 8-10 minutes later, a helical CT scan was performed from the level of the upper pole of the left kidney till the aortic bifurcation with an intravenous injection of 80 cc of injection Iohexol (350 mg Iodine/mL) at a rate of 4 mL/second with a scanning delay of 15-20 seconds, a collimation of 0.625 mm, table speed of 11 mm/sec and tube rotation period of 0.7 seconds during a single breath-hold. Curved multiplanar reconstruction, maximum-intensity projection and volume rendering algorithms were applied. Color Doppler imaging and DSA were also performed for all the patients. Conclusion: MDCT angiography was superior to color Doppler and DSA and showed 100% accuracy in detecting CRV and establishing it as the cause for UPJ obstruction as confi rmed at surgery.

Complications Conclusion: Imaging techniques are useful in monitoring the placement of a ureteral stent, as they can demonstrate eventual associated complications, thereby allowing quicker and effective diagnosis, with subsequent reduction of the morbidity. Purpose: Ureteric calculi are the main consideration in the majority of patients presenting with acute fl ank pain. Unenhanced spiral CT has become the imaging modality of choice in these patients not only because of its unrivalled ability to identify ureteric stones, but also because of its potential to identify other renal and non-renal pathologies. We report our experience with the use of CT KUB and the clinical incidence of non-calculus renal and non-renal pathology in patients presenting with acute fl ank pain with a provisional clinical diagnosis of ureteric colic.

We retrospectively reviewed 242 patients who underwent CT KUB from Jan 2005 to Dec 2005 for suspected renal colic. We excluded patients with a known renal disease or previously diagnosed renal stones. Results: 178 patients were included in the study after applying the exclusion criteria. Incidence of stone disease identifi ed by CT KUB was 45%. The majority of stones (44%) were found in the distal ureter and VUJ. Stone size of ≥5 mm was found in 34% of cases. Secondary signs were reported in nearly 65% of patients with stone disease. Alternative pathologies were identifi ed in 27 cases (15%). Conclusion: Unenhanced CT is an excellent modality for imaging patients with acute fl ank pain. Non-calculus renal and non-renal pathologies can often be identifi ed on unenhanced low-dose CT performed for suspected renal colic. A careful search for these alternative diagnoses should be made in all cases and particularly when the examination does not identify a ureteric calculus.

Imaging in urogenital emergencies N.A. Al-Nakshabandi; Riyadh/SA (nizarn@ksu.edu.sa)

Learning Objectives: 1) Familiarize the audience with the most urgent radiological emergencies in the urogenital system. 2) Learn the most appropriate approach for these emergencies and how to reach an appropriate differential diagnosis. 3) Learn the use of the appropriate modality. 4) Identify the radiological signs associated with each of these emergencies. Background: The use of imaging in urological emergencies is important to learn and manage. Careful attention to the urogenital involvement in emergency conditions is a very essential step in the radiological evaluation of these conditions Imaging Findings: Flank pain/ureteral colic is experienced by 2-3% of the population, with a 40-50% recurrence rate at 5 years. CT plays a valuable role in detecting the location of the stone and the presence of obstruction. Urosepsis occurs secondary to pyelonephritis, cystitis, prostatitis, or any other cause of obstruction. Ultrasound plays a valuable role in its diagnosis and intervention by placing a percutaneous nephrostomy catheter. Ultrasound is utilized in acute renal failure to assess' renal size, parenchymal thickness and presence of obstruction. CT with or with out cystogram is optimal for blunt abdominal trauma when kidney, ureter or bladder injury is suspected. Retrograde urethrogram can be done when a urethral injury is suspected. Ultrasound can easily differentiate orchitis from testicular torsion. It is also valuable in confi rming the diagnosis of testicular rupture.

The use of imaging in urogenital emergencies is of outmost importance. Examples of imaging and management will be given.

The role of ultrasound in infl ammatory bowel disease N. Bharwani, N. Stephens, J. Pilcher; London/UK Learning Objectives: 1. Discussion of the role of bowel ultrasound in infl ammatory bowel disease. 2. Pictorial demonstration of typical ultrasound fi ndings. 3. Advantages and disadvantages of ultrasound in IBD compared with other imaging modalities. Background: High-resolution ultrasound has recently become a recognised tool in the evaluation of infl ammatory bowel disease (IBD). With advances in ultrasound equipment and novel imaging techniques, this modality is increasingly being used to diagnose patients at initial presentation, assess disease activity, identify complications, and monitor response to therapy. Imaging Findings: This pictorial review will highlight the features seen in IBD on high-resolution ultrasound, both in and outside the bowel wall. We will outline the role of spectral Doppler in assessing the mesenteric circulation and that of power Doppler in the monitoring of patients. The latter half of the discussion will focus on more recent techniques beginning to be employed in the assessment of IBD. This includes the application of microbubble contrast agents using both power Doppler and harmonic imaging modes to try and measure mural infl ammation, and the role of non-absorbable, anechoic, oral contrast agents in distinguishing small-bowel strictures. Barium studies, CT, and MRI correlation will be provided, where appropriate. Conclusion: High-resolution ultrasound is an evolving modality in the management of infl ammatory bowel disease. It can effectively be used to evaluate patients with clinically suspected IBD at fi rst presentation, and also to monitor known patients with regard to disease activity, luminal and mesenteric complications. 

including metachronous adenomatous polyp and cancer and recurred/metastatic cancer. Representative cases for each category were selected and are presented with optical colonoscopic correlation. Imaging Findings: A colonic anastomosis typically presents as a web-like structure with a smooth and sharp border. Distortion of the normal shape of an anastomotic ring can be caused by both insignifi cant lesions and signifi cant lesions. Polypoid lesions at anastomotic ring are typically insignifi cant with protruded suture materials and suture granulomas being the most common etiology. Irregularities of the anastomotic ring such as irregular depression or elevation may represent anastomotic recurrences. Metachronous lesions have the usually morphology of a polyp or a mass at CTC elsewhere in the colon. CTC clearly shows perianastomotic recurrence or distant metastasis. Peritoneal metastatic implant may also be detected at endoluminal fl y-through of CTC by noting an extrinsic compression by the lesion. Conclusion: CTC is a benefi cial and noninvasive surveillance method for post-surgical colorectal cancer. Knowledge of and familiarity with the normal and abnormal post-surgical fi ndings at CTC will help increase the role of CTC in post-surgical follow-up of colorectal cancer. Colonic angiodysplasia has been increasingly recognized as a common source of acute and chronic bleeding in elderly patients, accounting for up to 50% of cases of obscure gastrointestinal hemorrhage. Currently, imaging assesment of gastrointestinal vascular lesions relies on invasive procedures such as endoscopy or angiography, but MDCT has gained acceptance as a minimally invasive technique for imaging of the vascular system. Procedure Details: We retrospectively reviewed 27 cases of colonic angiodysplasia diagnosed by MDCT during past 5 years. In 24 cases, the examination was performed due to acute or chronic recurrent bleeding when colonoscopy failed to show the cause. In 3 cases, colonic angiodysplasia was an incidental fi nding in abdominal vascular studies. The MDCT fi ndings include accumulation of ectatic and tortuous vessels within the colonic wall, early fi lling veins due to arterio-venous-type malformation development, enlarged arteries of the target area, and intraluminal contrast material extravastion in cases of active bleeding. Conclusion: MDCT is a useful tool for the diagnosis of colonic angiodysplasia especially in elderly patients with lower GI bleeeding when colonoscopy fails to establish the diagnosis, avoiding the need of invasive catheter angiography.

Impact of CT colonography with and without removal of diminutive polyps on colonoscopy demand A. Laghi 1 , C. Hassan 2 , R. Ferrari 1 , F. Purpose: To evaluate different combinations of magnetic resonance (MR) colonographic sequences and intraluminal contrast agents. Methods and Materials: 103 polyps, size from 3 to 10 mm, were created on the porcine colon. Forty-nine polyps were 5 mm or smaller and 54 were larger than 5 mm. MR colonography was performed with the three-dimensional T1-high resolution isotropic volume excitation (THRIVE) or multislice two-dimensional balanced fast fi eld echo (bFFE), using either the air enema or water-Gd. enema. We evaluated the presence or absence of each polyp in the MRC compared to the simulated polyps. The diagnostic performance of each MR sequence-contrast agent combination was assessed for detecting polyps. To compare air and water-Gd. enemas, polyp conspicuity was evaluated using a four-point scale under bFFE sequence. The results were analyzed using Wilcoxon's signed ranks test.

The bFFE using the water-Gd. enema showed greater diagnostic performance. It had a sensitivity of 95.9%, a specifi city of 100%, a positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 81.8% for polyps of 5 mm or smaller; and a sensitivity, specifi city, PPV, and NPV of 100% for polyps larger than 5 mm. The bFFE using the water-Gd. enema was also signifi cantly better at enhancing polyp conspicuity compared to the air enema. Conclusion: MRC with bFFE using a water-Gd. enema provided the greater conspicuity, with excellent diagnostic performance.

Role of FDG-PET/CT in the local staging of colorectal cancer E. Selva, P.P. Mainenti, G. Avitabile, L. Camera, G. Storto, L. Pace, M. Salvatore; Napoli/IT Purpose: To evaluate FDG-PET/CT as a diagnostic tool in the assessment of primary tumor extent (T) and lymph node metastases (N) in patients with colorectal cancer. Methods and Materials: Twenty patients with diagnosis of colorectal cancer underwent FDG-PET/CT before surgery. T and N parameters were evaluated on images. < T2 lesions were defi ned as tumours confi ned to the bowel wall in absence of extra parietal radio-tracer uptake; T3 lesions as tumours with spiculated outer contour or with rounded or nodular advancing edges showing radio-tracer uptake; T4 lesions as tumours infi ltrating into adjacent organs in which radio-tracer uptake was present; N1 as FDG uptake in a cluster of three nodes each less than 1 cm in diameter or in a single node measuring at least 1 cm; N2 as FDG uptake in more than three nodes regardless of their size. T and N PET/CT staging was compared to histopathology. Results: 20 adenocarcinomas were identifi ed: 1 lesion was classifi ed as T1, 3 as T2, 16 as T3; lymph-nodal involvement was present in 9 cases (5 N1 and 4 N2). All lesions were correctly identifi ed and localized on PET/CT images. FDG-PET/CT correctly identifi ed T stage in 18 of 20 (90%) patients (3/4 < T2 and 15/16 T3). N stage was appropriately determined in 17 of 20 (85%) patients (9/11 N0, 4/5 N1 and 4/4 N2). Conclusion: FDG-PET/CT is a useful diagnostic tool in evaluating T and N parameters in patients with colorectal cancer despite the absence of iv contrast medium on CT scan.

Why did I miss appendicitis on abdominal CT? A pictorial review of appendix pathology on CT M.A. Hanif, R. Shukla, R. Young; Bristol/UK (asadhanif@doctors.net.uk)

Learning Objectives: Appendicitis is one of the most common causes for an acute abdomen, which can be missed on CT abdomen by the resident on call. We aim to present this poster as a pictorial review of different appendiceal pathologies with atypical presentations. This will help us analyse the factors leading to false-negative results on CT. Background: Appendicitis is a great mimicker of disease, not just clinically but also radiologically -especially in the adult patient. The diagnosis of acute appendicitis on computed tomography (CT) of the abdomen can prove to be diffi cult at times. Variations in the position, length and location of the vermiform appendix along with the differences in the amount of intra-abdominal fat and clinical presentations contribute to this seemingly simple diagnostic dilemma. Criteria for the diagnosis of appendicitis on CT are well documented in the literature. Learning Objectives: To describe acquisition parameters of CT-colonography protocols using different scanners generations moving from single slice spiral Ct to the 64-MDCT. Background: Nowadays, the "panorama" of technical approaches for CTC is expanding offering a wide spectrum of different possibilities. As technology continues to advance, there will be a continuing need to reassess the relative tradeoffs between scan width, image noise, patient dose, image artefacts, breath-hold times, and the number of reconstructed images to be viewed and archived. Procedure Details: We will discuss the relationship between collimation, tube current settings, patient dose exposure and accuracy in polyp detection of various CTC protocols valid for different scanner generations. We will offer some practical guidelines for CTC technique based on evidences of literature and on our personal experience of more than 800 CTC examinations performed on different scanners generation including a 64-MDCT (VCT; GE). Conclusion: A single scanning protocol with identical parameters for all scanners and patients cannot be recommended due to technological differences as well as different clinical indications to CTC. What is possible is to offer general guidelines according to the consensus statement on CTC. Collimation should not be larger than 5 mm for SSCT and no larger than 3 mm for MDCT. With the advent of 64slice MDCT, sub-millimeter collimation will be mandatory, although clinical benefi ts are still unclear. was obtained before and 60 seconds after intravenous administration of Gd-chelate. MR images were evaluated in conference by two observers by seeking for bowel abnormalities and were correlated with conventional colonoscopy (CC) in all cases and with surgery in 7/18 patients. Results: MRC could be successfully performed in all cases, whereas CC was incomplete in 5/18 patients. MRC correctly defi ned bowel wall thickening, stenosis and extension of the infl amed colon in 4/5 patients with ulcerative colitis. In 10/12 patients with Crohn disease, involvement of both large and small bowel was demonstrated; perianal abscesses (n=2) and fi stulas (n=2) were also identifi ed. In one remaining case, no abnormality was found at MRC and fi nal histological diagnosis was not surely diagnostic for IBD. Conclusion: MRC with fecal tagging technique is a promising, minimally invasive technique for evaluation of the bowel in patients with suspected IBD. It can be used for the assessment of disease's extension, especially for those who cannot have CC due to severe pain and fecal residua.

Abnormal masses of the right iliac fossa: Spectrum of imaging fi ndings A.E. Mahfouz, H. Sherif, N. Morad; Doha/QA (mahfouzae@yahoo.com)

Learning Objectives: To learn the differential diagnosis of abnormal masses of the right iliac fossa and to illustrate the peculiar imaging features of each of these different masses with histopathological correlation. Background: Diagnosis of patients with symptoms related to the right iliac fossa may be diffi cult due to the wide variety of pathological processes which may involve the right iliac fossa. Imaging may be helpful in diagnosis. Imaging Findings: Abnormal masses of the right iliac fossa illustrated in this educational exhibit include appendicitis, appendicular abscess, mucinous adenocarcinoma of the appendix, Cecal carcinoma, typhlitis, omental strangulation, infl ammatory bowel disease, ileocecal tuberculosis, and ileocolic intussusception as well as abnormalitis outside the gastrointestinal tract, which may be considered in the differential diagnosis. Peculiar imaging features on different imaging modalities including ultrasonography, multidetector CT, scintigraphy, barium studies, and MR imaging with their pathological correlation will be presented. Conclusion: Modern imaging modalities are helpful for the correct diagnosis of of patients with symptoms related to the right iliac fossa.

The Purpose: Preoperative radiotherapy with or without chemotherapy in the management of patients with locally advanced rectal cancer allows to decrease tumor size and stage, improves sphincter preservation and the ability to perform a curative resection. The aim of this study was the estimation of the role of MDCT-colonography in the pre-surgical staging and restaging of rectal cancer, treated with pre-operative neoadjuvant therapy. Methods and Materials: Twenty-eight selected patients with histologically proven rectal cancer with initial stage T3/4, N+ and M0 were studied. All patients underwent MDCT-colonography with use of a standard protocol for preoperative staging before and 2-4 weeks after radio/radiochemotherapy. Pre-operative TNM staging was correlated with surgical/histological fi ndings. Results: Histopathological evaluation of the resected tumor revealed complete response in one patient, partial response in 18 and stable disease in 9. Reduction in tumors size was signifi cantly greater in responders than in non-responders and indicated a good reaction to therapy. 67% patients showed tumor downstaging and only 7% nodal downstaging after TNM restaging. MDCT correctly staged T in 22 (78.5%) cases, T was overstaged in 6 (21.5%) due to peritumoral post-therapeutic fi brosis. MDCT correctly staged N in 21 (75%), overstaged in 5 (17.8%) and understaged in 2 (7.2%) cases. Conclusion: MDCT-colonography is an accurate procedure for pre-operative staging and restaging TNM classifi cation in patients with rectal cancer treated with neoadjuvant therapy and can be used for treatment planning. The greatest diffi culty was distinction between T2 and T3 stage due to peritumoral post-therapeutic fi brosis. All patients underwent chemoradiation therapy (CRT). DWI was performed using a 1.5 T whole body scanner equipped with a phased-array body coil. A single-shot spin-echo type of echo-planar sequence that provided diffusion weighting in the direction of slice selection was used to obtain DW images. The corresponding bvalue to the diffusion sensitizing gradients were b=1000 s/mm 2 . We evaluated the DW images measuring the ADC value of the tumor and compared it with the effect of CRT. The therapeutic effect was assessed according to the WHO criteria, using contrast-enhanced MDCT and esophagography 4 weeks after the treatment. Results: Eight patients were responder and 5 were non-responder. All tumors were detected by DWI (accuracy 100%). The mean ADC value of the tumor was signifi cantly lower than that of the normal esophagus (1.004 x 10 -3 mm 2 /s vs 1.756 x 10 -3 mm 2 /s, p < 0.0001). The mean ADC value of the responder group was signifi cantly higher than that of non-responder group (1.187 x 10 -3 mm 2 /s vs 0.830 x 10 -3 mm 2 /s, p=0.0054).

Conclusion: This non-invasive modality could be a valid clinical diagnostic modality to predict the outcome of CRT of advanced esophageal cancer.

Risk Purpose: The aim of the study was to evaluate the role of Doppler ultrasonography (US) of the portal vein in assessing the risk of esophageal variceal bleeding in patients with liver cirrhosis. Methods and Materials: Transabdominal Doppler US and endoscopy were performed in 38 patients (26 male, 12 female, mean age 54.8 years) with liver cirrhosis and esophageal varices. The variceal size and the presence of red signs were determined by endoscopy. Following US parameters of the portal vein were recorded: diameter and cross-sectional area, blood fl ow velocity and blood fl ow volume, perfusion pressure gradient (PPG), and congestion index (CI). Child-Pugh score of liver function was also determined. The US parameters were compared to the endoscopic signs of esophageal bleeding risk.

Results: Values of portal diameter, cross-sectional area, blood fl ow volume and CI were signifi cantly higher, while PPG was lower in patients with, than in patients without variceal red signs. Only diameter, cross-sectional area, and blood fl ow volume were signifi cantly different among groups of patients with different variceal sizes. The blood fl ow velocity did not depend on the presence of red signs and variceal size. In addition, recorded US parameters did not reach level of significance between groups of patients with different Child-Pugh score. The sensitivities, specifi cities, and areas under ROC curves of the analyzed US parameters were 62.5-82%, 47.2-79.8%, and 0.79-0.89, respectively. Conclusion: According to our results, transabdominal Doppler US might be of value in non-invasive assessment of the risk of esophageal variceal bleeding in patients with liver cirrhosis. A digital cineradiography with 6 frames/second acquisition was performed in all patients using bolus of 30 ml of liquid (60% weight/volume) barium. In 10 patients standing in the left posterior oblique position and prone in the right posterior oblique position, the oesophagus and oesophagogastric junction were also examined. The water siphon test was performed at the end of the procedure. Results: In all patients, the evaluation of oesophageal motility disorder was possible. In 18 of them, the grade of the disorder was high and barium retention in the oesophagus was also detected. Owing to the stagnation of liquid barium in the terminal oesophagus, the evaluation of oesophagogastric junction was possible only in 10 patients. Of these patients, 7 presented a hiatus hernia and 8 a gastrooesophageal refl ux. Conclusion: Digital cineradiography is a suitable technique for evaluating the functional abnormalities of the oesophagus in patients affected by Sclerodermia. Learning Objectives: To present a pictorial review of the radiological appearances of Achalasia and Pseudoachalasia with emphasis on endoscopic correlation. Background: Barium swallow remains a valuable imaging modality in patients presenting with dysphagia. Pathologies such as achalasia and pseudoachalasia can be diffi cult to distinguish on barium swallow as typical fi ndings may not always be apparent. Recognising the various radiographic appearances by the radiologist is critical for prompt and accurate patient management. Imaging Findings: We present a case series of achalasia and pseudoachalasia on barium swallow encountered at our institution. We emphasise the differences between the two pathologies both on imaging and on text as a learning experience. We also provide a review of the existing literature with reference to our experience. Conclusion: Barium swallow is an established method for evaluating patients with dysphagia. However achalasia and pseudoachalasia still remain diffi cult to distinguish; so awareness of the potential pitfalls with endoscopic correlation in all cases is emphasised to avoid radiological misdiagnosis.

Late evaluation of the swallowing function in patients with maxillofacial gunshot injuries by multimodality radiologic and complementary methods Z.U. Coskun 1 , S. Ozturk 2 ; 1 Bilkent, Ankara/TR, 2 Etlik, Ankara/TR (unsalcoskun@yahoo.com)

Purpose: Maxillofacial (MF) gunshot wounds having a tract between the mouth fl oor and the naso-orbital region may result in long-term swallowing disorders. Here, we aimed to show late functional outcomes of the primary surgical treatments by using objective radiologic and complementary studies. Methods and Materials: 20 patients were included in the study. The mean age was 21±3. Free osteocutaneous fi bula fl aps, iliac or calvarial bone grafts were used with fasciacutaneous fl aps. Dento-palatal restorations were accomplished with dental and prostetic obturator implants. Functional outcomes were assessed by: Videofl uoroscopy, Cine-MRI, Submental USG, Fiberoptic endoscopic swallowing study (FEES), Functional EMG. The results were compared to the control group (N:10) statistically.

Videofl uoroscopic studies showed pooling in vallecula and pyriform sinuses (n:16), delayed pharyngeal (n:12) and oral transit times (n:12), spilling out due to oral incompetence (n:10), nasal regurgitation (n:8), sublingual pooling (n:4), multiple swallowing action (n:3), and aspiration (n:2). Cine-MRI revealed reduced laryngeal elevation (15.4 mm) and epiglottic angle (10.5 o ). Discordance and impaired oral fl oor muscles were observed. Submental USG showed insuffi cient tongue movement resulting in bolus formation and transit impairment (n:8), restricted hyoid elevation (n:12), and submental muscle defects (n:12). FEES revealed pooling in vallecula and pyriform sinuses (n:16), delayed epiglot closure (n:12) and impaired swallowing apnea (n:2). Functional EMG showed lower amplitude of submental and pharyngeal constrictors (n:12). Conclusion: Clinically, knowing the radiopathologic fi ndings in such patients may help the clinician in determining an algorithm to manage the secondary deformities as well as adding new surgical techniques such as replacement of submental muscles by functional muscle fl aps during primary surgery. 134 patients were treated with surgery alone and 84 patients (29 with 5x5 Gy and 55 with 60 Gy) were treated with preoperative pelvic radiotherapy. A complete postoperative histopathological examination was used as the gold standard. Results: In pathology 73 of 218 (33%) tumors were classifi ed as T0-T2, and 145 (67%) were classifi ed as T3-T4. TRUS had an accuracy of 90% in detecting penetration of the rectal wall in the 134 patients treated with surgery alone. The accuracy of TRUS in patients treated with 5x5 Gy was 82.3% (NS), and in patients treated with 60 Gy, the accuracy was 55.2 % (p < 0.001). A high sensitivity was noted in all groups; however, the specifi city of TRUS rapidly decreased to zero with increased pelvic radiotherapy intensity, as the false-positives increased because of tumour shrinkage. This change in accuracy was not seen to the same extent with regard to lymph node metastases.

Conclusion: TRUS has a high accuracy in patients treated with surgery alone.

The T-staging accuracy of TRUS is low in patients receiving high-dose pelvic radiotherapy due to down staging. Purpose: The purpose of this study is to evaluate perfusion CT in assessing pathological features of rectal cancer before surgery. Methods and Materials: Forty consecutive patients (23 men, 17 women; median age 62.8 years) with rectal cancer underwent perfusion CT, using the commercially available CT Perfusion 3 software (GE Medical Systems, Milwaukee, WI). All patients were followed by surgery, and we retrospectively investigated the correlations between perfusion parameters and pathological features (wall invasion, histological differentiation, lymph node metastasis, Dukes' classifi cation). Statistical analysis was performed with Mann-Whitney U test for comparison of two data sets, and Kruskal-Wallis test for comparison of multiple data sets. P < 0.05 was considered to indicate a statistically signifi cant difference.

Results: There were no correlations between perfusion parameters and wall invasion. Well-differentiated tumors showed signifi cantly higher blood fl ow than the moderately-differentiated tumors (P = 0.03). There was a signifi cant tendency for the tumor with low blood fl ow, low blood volume or long mean transit time to show lymph node metastasis (P = 0.006, 0.01, 0.001, respectively). And there was a signifi cant correlation between Dukes' classifi cation and blood fl ow (P < 0.0001), blood volume (P = 0.002), mean transit time (P = 0.001), and permeability surface area product (P = 0.004).

In the near future, perfusion CT may help to assess pathological features of rectal cancer before surgery. 

within the node versus the size of the total node, categorized as 50%. This ratio was objectively calculated (RatioA) by the long and short axis diameter measurements of both the area of white region within the node and the total node. Regions of interest (ROI) were used to measure the signal intensity (SI) within muscle (SImuscle), total node (SITN), white (SIwhite) and dark (SIdark) region within the node. These measurements were used to calculate the ratios: SIwhite/SIdark and SITN/SImuscle. A receiver operating characteristic (ROC) analysis was performed.

Results: A lesion-by-lesion analysis of 228 lymph nodes was feasible. The area under the ROC curve (AUC) of border, short and long axis of the total node were respectively 0.66, 0.65 and 0.72. The AUC for the estimated percentage and measured RatioA of white region within the node were 0.93 and 0.95, respectively. The ROI could accurately be positioned in 207 lymph nodes. The AUC of the ratios: SIwhite/SIdark and SITN/SImuscle were respectively 0.76 and 0.90.

The estimated ratio of white area within the node and the measured Ra-tioA were very accurate for distinguishing between malignant and benign nodes.

Pre-surgical evaluation with positron emission tomography (PET) and magnetic resonance imaging (MRI) of patients with locally advanced rectal cancer treated with neo-adjuvant radio-chemotherapy L. Balestreri, E. Borsatti, R. Talamini, M. Cimitan, S. Morassut; Aviano/IT (lbalestreri@cro.it)

Purpose: To compare the diagnostic performance of PET and MRI in correctly restage patients with advanced rectal cancer treated with neo-adjuvant radiochemotherapy before surgery.

Twenty-three patients with advanced rectal cancer (T3-T4) were studied with PET and MRI before and after 5-fl uorouracil or Raltitrexed-based chemotherapy and 45-50 Gy of radiation therapy. Pre-surgical scanning was performed 6 to 8 weeks after the end of the chemoradiation; the results were compared to the surgical specimen. Particularly for PET, tumour response was considered evaluating Standardized Uptake Value (SUV) percentage decrease related to Tumour Regression Grading (TRG) at pathology. For MRI, tumour response was considered evaluating: (1) tumour extension and size according to the TNM system.

(2) Circumferential Resection Margin (CRM) measurement assessing the distance between extramural tumour and mesorectal fascia. Results: Strong correlation (Spearman correlation coeffi cient r = -0.6) was found in between SUV decrease > 80% and TRG values of 1 and 2 (no residual disease or microscopic active disease). Strong correlation (specifi city 100%, sensitivity 71%) was found between CRM measurement with MRI and on the surgical specimen.

No statistically signifi cant correlation was found between T measurement with MRI and on the surgical specimen.

While PET provides reliable metabolic information about tumour response to therapy, MRI provides reliable measurement of CRM. Both modalities must be performed to correctly restage patients before surgery. Background: Although adenocarcinoma is the most frequently encountered rectal tumor, familiarity with the cross-sectional imaging features of less common anorectal tumors as well as of their differential diagnosis is important because their prognosis and treatment are different. In this exhibit, we will describe the CT and MRI features of such lesions based on a series of 30 patients treated in our department since 2003 with a pathologic correlation. Procedure Details: Mucinous anorectal adenocarcinomas are characterised by a markedly hyperintense content on T2-weighted images, an enhancing solid component within the mass and their highly infi ltrative behaviour. Villous tumors are large masses fi lling the rectal lumen and displaying frondlike projections. Anorectal stromal tumors are large, well-marginated masses expanding the rectal wall and lack perirectal adenopathy. Lymphomas display marked concentric wall thickening engulfi ng the rectum, with luminal restriction but minor obstruction and adenopathies. Linitis and rectal metastases display a circumferential thickening of the rectal wall over a long segment. Other uncommon tumors include carcinoid tumor, melanoma, anal condyloma. Differential diagnosis include Crohn disease, diffuse rectal angiomatosis, changes after radiotherapy, rectal endometriosis, diverticulitis.

Identifying key specifi c CT and MR imaging features can be helpful in suggesting a diagnosis. MRI is a modality of choice to evaluate unusual anorectal neoplasms.

High To review the current role of MRI in the evaluation of these lesions. Background: Developmental cysts are the most common retrorectal cystic lesions in adults. They are classifi ed as epidermoid cysts, dermoid cysts, enteric cysts according to their histopathologic features. They may present with symptoms or with a complication such as infection or malignant degeneration. Their differential diagnosis

We review the MR imaging fi ndings with pathologic correlation of presacral cystic masses based on a series of 25 patients treated in our department. Imaging Findings: Developmental cysts, among which tailgut cysts are the most frequent are characterized by well-defi ned, multilocular cysts with "daughter cysts". Their wall is usually thin unless they are complicated. An enhancing wall with peri cystic infl ammation suggests infl ammation and additional internal enhancement evokes malignant degeneration. Their signal intensity is variable, usually homogeneous, either isointense to muscle on T1-weighted images and isointense to fat on T2-weighted images or hyperintense on T1/hyperintense on T2 depending on their content. Differential diagnosis includes anterior sacral meningocele, recurrence of mucinous rectal adenocarcinoma, cystic lymphangioma, necrotic sacral chordoma or leiomyoma, pyogenic abscess, schwannoma, peritoneal pseudocyst. Conclusion: Most lesions of the retrorectal space are developmental cysts but the differential diagnosis must be known. Knowledge of the key imaging features of the retrorectal cystic lesions may help suggest the diagnosis and the information needed to plan treatment.

Preoperative N staging of rectal cancer evaluating from morphological feature using magnetic resonance imaging T. Sazuka, S. Okazumi, K. Shuto, T. Aoyagi, H. Makino, R. Mochizuki, T. Ochiai, N. Yanagawa; Chiba/JP Purpose: The purpose of this study is to evaluate the accuracy of magnetic resonance imaging (MRI) in N staging of rectal cancer and to compare histological fi ndings. Methods and Materials: Eighty-six patients of rectal cancer were enrolled in this study. All of the patients underwent surgery and proved histologically. Prior to treatment, MRI was performed with T2-weighted fast spin echo sequences using a 1.5 T whole body scanner equipped with a phased-array body coil. Following fi lling the rectum with air of 200-250 ml from a placed tube, images were acquired with a slice thickness of 8 mm. Every reconstruct axial, coronal and sagittal images of each node was evaluated. We classifi ed lymph nodes over 5 mm by 3 morphological features as follows: solitary/ confl uent, margin clear/ spicular, shaped fl at/ round. And we assessed those features in comparison with histological fi ndings.

Results: A total of 313 nodules were evaluated. All of confl uent nodules (N=11) were histologically metastatic (PPV 100%, specifi city 100%). When we defi ne metastatic node as any features of confl uent nodule, irregular margin or round shaped, the sensitivity was 91% and the specifi city 91%, PPV 78% and NPV 97% in comparison with histological fi ndings. Conclusion: This diagnostic method classifying by morphological features is noninvasive and may be valid with an acceptable detectability by no means inferior to enhanced or radiological modality.

Dynamic magnetic resonance imaging (MRI) evaluation of levator ani muscle (LAM) in patients with wall prolapse and intussusception pathologies of the rectum A. Salzano, V. Nocera, G. Cavallo, E. Montemarano, P. De Feo, A. Nunziata; Naples/IT (tonikus@libero.it)

Learning Objectives: To describe MRI dynamic appearance of LAM in patients with rectal wall prolapse and intussusception, outlining the role and the advantages of dynamic MRI for the assessment of anatomic and functional study of LAM and evacuation disorders. Background: Dynamic MRI allows to evaluate morphology and pathomorphologic changes of the LAM during defecation. Defecography well assesses rectal prolapses, but does not provide imaging of muscles of pelvic fl oor except indirect signs. Dynamic MRI provides a whole and direct visualization both anatomical and functional of LAM and rectal prolapses. We illustrate a study of 23 female subjects (mean age of 61 years; range 47-74 years) previously investigated by Defecography in order to obstructed evacuation. Imaging Findings: Dynamic MRI was carried out in different dynamic phases of pelvic fl oor, in Breathe Hold using T2-weighted scans. We diagnosed 16 rectal wall prolapses and 8 intussusceptions; all patients had rectocele and perineal descent syndrome. LAM had reducted thickness in 16 cases and alterated signal in 4 cases. Levator hiatus was large in 19 cases in the coronal plane with a typical shape of large cone. We focused a relationship between hiatal area, movements of rectal walls and descent of pelvic fl oor. Conclusion: Dynamic MRI is considered a novel noninvasive imaging method of investigation in comparison to Defecography, to understand the dynamics of LAM and the pelvic fl oor descent disorders. MRI provides better the relationship of rectal intussusception and wall prolapse related to pelvic organ mobility and dynamic shape changes of LAM.

Diagnosis and follow-up of anoperineal fi stuals with phased-array MRI: A pictorial review F. González, G. Blanco, C. Juanco, N. Valle, M. Lopez, M. Silvan; Santander/ES Learning Objectives: To describe the anatomy and imaging features of acquired anorectal fi stulas. To identify the MRI fi ndings in the various types of anorectal fi stulas. To review the role of MRI in the assessment of acquired anorectal fi stulas. Background: The most commonly encountered and known anorectal fi stulas are anorectoperineal fi stulas occuring in Crohns disease. However, there is a variety of less common fi stulas involving the anorectum. Their causes include infection, infl ammation, neoplasms, trauma and iatrogenic injury. Pelvic MRI assessment has proved useful in the evaluation of fi stulas and has become an important part of diagnostic work-up before proper case management. Imaging Findings: We illustrate the MR fi ndings in fi stulas involving the rectum or anal canal or ileal or colonic pouch (in case of previous surgery) and the vagina, uterus, prostate, urethra, bladder, and ileum. We also present the features of complex anoperineal fi stulas. The current role of MRI is discussed. We emphasize the role of MRI in the follow-up after medical or surgical treatment. Conclusion: Phased-array pelvic MRI is an accurate technique for the identifi cation of acquired anorectal fi stulas and their complications. MRI exam is a noninvasive diagnosis method that allows us an accurate diagnosis and follow-up in patients with anoperineal fi stulas. Imaging Findings: Small-bowel lymphomas are presented in wide spectrum of appearances included aneurismal dilatation, intra luminal polypoidal mass, mesenteric mass with irregular infi ltrating borders causing thickening of the walls and narrowing of the lumen and it may present just as diffuse circumferential mural thickening of the bowel walls with irregular narrowed lumen. MR SBFT offers the advantage of excellent soft-tissue contrast and multiplanar imaging capabilities and absence of ionizing radiation over other modalities in studying small bowel lymphoma. Over a 4-year period, we reviewed 260 MR SBFT examinations for evidence of small bowel lymphoma. In all, 14 cases were identifi ed and subsequently histologically confi rmed. We provide a detailed radiological review of the appearances of these tumors at MR SBFT. Conclusion: MR imaging of the small bowel has moved in the recent years and the knowledge of the typical MR SBFT appearance of small bowel lymphoma may aid the radiologist to suggest the diagnosis. Purpose: To evaluate using magnetic resonance the effi cacy of oral infl iximab therapy in perianal fi stulizing Crohn´s disease patients. To compare clinical and MRI fi ndings in these patients, using the perianal Crohn´s disease activity index (PCDAI) and magnetic resonance imaging-based score (MRS). To evaluate the effi cacy of MRI in the diagnosis and follow-up of this pathology. Methods and Materials: Patients with perianal fi stulas due to Crohn´s disease were enrolled into a prospective study, and were evaluated with pelvic MR previous to treatment and after a long-term follow-up of 24 months, in order to observe the evolution of fi stulous pathology. We use a 1.5 T system (Magnetom Avanto Siemens®) with a phased-array coil. We applied the MRS modifi ed from Assche to the images obtained. The clinical response was evaluated with the PCDAI described by Irvine. Results: Twelve patients were included in our study. Six (50%) achieved complete responses, verifi ed with both PCDAI and MRS. Five (41.6%) showed no changes in MRS with partial response in the PCDAI and 1 (8.3%) showed no response in both MRS and PCDAI. Conclusion: Oral Infl iximab is an effective treatment for patients with perianal fi stulas due to Crohn´s disease. MR is a good method for the diagnosis of the perianal Crohn´s disease and for the follow-up and evaluation of the treatment of these patients. The differences of the results in clinical and MR scores may be due to the subjective index that are evaluated in PCDAI and the ¨placebo¨effect of the treatment.

Is virtual enteroscopy an acceptable method for detecting Peutz-Jeghers poliposis in the small bowel? E. Turupoli, G. Tóth, K. Szeidl, Á. Komezei, Á. Szilvássyné Takács; Budapest/HU (turupoli@freemail.hu)

Purpose: Hamartomas are usually considered histologically benign, but in the case of Peutz-Jeghers patients, there are reports of malignant changes in the polyps. We tried to assess the usefulness of virtual enteroscopy for the assessment of Peutz-Jeghers polyposis in the small bowel. Our goal was to reach a good distension in the small bowel by virtual enteroscopy.

In 15 patients with known Peutz-Jeghers polyposis in the stomach and colon, CT virtual enteroscopy was performed. Patients were examined with a 16-row CT scanner using the following parameters: slice 1 mm, with overlap scans, reconstruction interval 0.5 mm. 120 ml i.v. contrast agent was administered at a rate of 3 ml/s with a scan delay of 50 s. We evaluated mural thickening, mural enhancement, stenosis, praestenotic dilatation. The results of MDCT enteroscopy were compared with selective enterography and surgery. Selective enterography and surgery were considered the gold standard.

Results: Good small bowel distension was obtained in 13 cases, and suffi cient in 2 cases. MDCT virtual enteroscopy showed 45 i.v. contrast-enhancing polypoid lesions in 8 patients. Thirty-three lesions were smaller than 10 mm and 12 were larger than 10 mm. Two polyps caused intussusception. Selective enterography showed 36 polyps smaller than 10 mm, and 12 larger than 10 mm. MDCT virtual enteroscopy had an overall per-lesion sensitivity of 91.6% for lesions smaller than 10 mm, and 100% for lesions larger than 10 mm. Conclusion: MDCT virtual enteroscopy in Peutz-Jeghers syndrome showed a high sensitivity in detecting polyps smaller than 10 mm. 

Coeliac disease -incidence and radiological fi ndings of associated malignancy E. DeLappe, C. Cronin, C. Meehan, C. Roche, J. Murphy; Galway/IE Purpose: Enteropathic-associated T-cell and B-cell lymphomas are recognised associations of coeliac disease; however, the exact prevalence is unknown. The purpose of this study was to determine the prevalence of associated gastrointestinal lymphoma or other malignancy in patients with chronic gluten-sensitive enteropathy. We describe the radiological features and distribution of these malignancies in our subject population.

We retrospectively reviewed the radiological and pathological fi ndings of gastrointestinal tract malignancies in a total of 363 patients with coeliac disease referred to our institution over a fi ve-year period. Assessment included disease presentation, location (duodenal, jejunum, ileum), stage and radiological features (wall thickening, abnormal mucosal pattern, local nodal involvement). We also reviewed the radiological fi ndings and prevalence of extragastrointestinal malignancies.

Results: A total of 14 new cancers were diagnosed in the total population sample (3.9%). Of these, 5 had a diagnosis of oesophageal cancer (1.4%) and 3 (0.8%) had lymphomatous involvement of the gastrointestinal tract. There was a signifi cant increased risk of both oesophageal cancer and gastrointestinal lymphoma compared to that of an age-matched population (p < 0.05). We identifi ed a number of other gastrointestinal and extra-gastrointestinal malignancies in the sampled group including duodenal, colon, bladder, lung, ovarian, and carcinoid with no statistically signifi cant increased risk. Conclusion: Although coeliac disease has been shown to have an association with gastrointestinal lymphoma, other gastrointestinal malignancies such as oesophageal tumours also occur increasingly in such patients. This possibility must be considered when patients with known coeliac disease present with gastrointestinalrelated symptoms, which are atypical for their primary condition.

Duodenal and paraduodenal lesions: Imaging fi ndings G. Pekindil; Manisa/TR (pekindilg@yahoo.com)

Learning Objectives: To illustrate imaging features of various developmental, infl ammatory, neoplastic, traumatic and postsurgical processes that are located in or adjacent to duodenum. Background: Although primary diseases of doudenum are rare, several primary and secondary processes may involve duodenum due to its both intra and extraperitoneal localization, proximity to pancreas, stomach, hepatobiliary and intestinal system. Procedure Details: Duplication, annular pancreas, malrotation and transient paraduodenal hernias are rarely seen congenital anomalies whereas diverticula may be seen more frequently. Infl ammatory wall thickening may arise from ulcers, pancreatitis, Crohn's disease, Coeliac disease, Henoch-Schonlein purpura. Many adjacent infl ammatory pathologies such as appendicitis, pancreatitis, cholecystitis may also have düodenal wall involvement and may cause "Sentinel loop" apperence of dilated duodenum with air-fl uid levels. Duodenal dilatation may arise from superior mesenteric artery syndrome. Primary adenocarcinoma, paraganglioma, liposarcoma, GIST, lymphoma, Menetrier disease may cause noeplastic involvement of duodenum. Also, metastatic lymphadenopathies of seminoma, mesothelioma, lymphoma may locate around duodenum. Walls of duodenum may be thickened from adjacent malignancies such as cholangiocarcinoma, adenocarcinomas of stomach, colon and pancreas. Cystic extrensic compression may arise from choledococel, intestinal lympangiectatic cysts, choledochal cyst, pseudocysts, policystic disease. Foreign bodies located in duodenum such as metallic nail and traumatic hematoma can be revealed by CT. Chlodecoduodenostomy, Whipple operation and gastrojejunostomy may cause several changes of duodenum.

Since several different pathologies may affect or may arise from duodenum, radiologist should pay attention to duodenum as much as other adjacent organs in the interpretation of many sectional imaging modalities.

Utility of MDCT enteroclysis in the evaluation of gastro-intestinal bleeding in small bowel diverticulosis: A pictorial review G. Tóth, L. Tóth, P. Magyar, E. Turupoli, K. Hüttl; Budapest/HU (totgez@freemail.hu)

Learning Objectives: While small bowel diverticulosis is a rare entity and usually asymptomatic, it may cause acute or chronic symptoms and complications. Because of its rarity, diagnosis is often delayed, resulting in unnecessary morbidity and mortality. Nowadays, the diagnosis of small bowel diseases is frequently made by MDCT enteroclysis. We present and discuss the typical fi ndings of MDCT enteroclysis in 6 cases. Background: Small bowel diverticulosis is a rare disorder found in 0.2-3% of the adult population. Most small bowel diverticula remain asymptomatic and are detected as an incidental fi nding, but they can also present a wide spectrum of complications, such as acute diverticulitis, hemorrhage, intestinal obstruction, perforation, malabsoption, and present as diffi cult diagnostic challenge. Acquired small bowel diverticulosis predominantly involves the proximal jejunum, and is located on the mesenteric aspect of the small bowel, while the congenital Meckel diverticulum is located on the antimesenteric aspect of the ileum, 30-60 cm from the ileocecal valve. 

Ninety-three patients with suspected small bowel tumor were examined with a sixteen-row CT scanner (Brilliance Power 16), using the following parameters: Coll. 16x0.75 mm with overlap scans, reconstruction interval 2 mm, after administration of methylcellulose by nasojejunal tube, before and after infusion of 120 ml iv. contrast agent, at the rate of 3.5 ml/s, with a scan delay of 50 seconds. In all the cases, multiplanar and curved planer reformatted images were performed. We evaluated mural thickening, mural enhancement, stenosis, praestenotic dilatation, perienteric reactions, lymph node enlargement. Results were compared with SBE and surgical fi ndings. Results: MDCT detected 26 lesions, and SBE showed 23 pathological lesions. The comparison with SBE showed 2 CT false-positive cases due to poor bowel distension. Three SBE false-negative cases were due to the small polipod lesions (< 10 mm). The fi nal diagnosis was adenocarcinoma in 5 patients, carcinod tumor in 3 patients, Peutz -Jeghers poliposis in 1 patient, adenomatous polyps in 3 patients, lymphoma in 3 patients, leiomyoma in 2 patients, leiomyiosarcoma in 1 patient, CD in 6 patients and adhesions in 2 patients. We found enlarged lymph nodes in 13 patients, and liver metastases in 7 patients. MDCT fi ndings correlated well with the surgical fi ndings. Conclusion: MDCT enterography is a useful and reliable method for the diagnosis of small bowel tumors. Background: Adult small bowel intussusception has been regarded as a condition that always required surgery because up to 90% of the surgical reports said to be associated with a lead point abnormality. However, with the growing use of cross-sectional imaging in the evaluation of patients with abdominal complaints, the detection of enteric intussusception without a visible lead point disease has increased, creating a challenge in determining its diagnostic signifi cance and therapeutic approach. Imaging Findings: At CT, the presence of a bowel within bowel confi guration is pathognomonic for intussusception, having three different patterns depending on the severity and duration of the disease process. Intussusceptions without a lead mass are usually transient, small and non-obstructing. Experiments say they are due to disturbances in peristalsis and require only conservative observation. A lead point intussusception usually appears as a long abnormal target-like mass that may be associated with proximal bowel obstruction. Identifi cation of the lead mass is not always easy; however, once recognized, surgical treatment should be recommended. Conclusion: Incidental enteric intussusceptions are being increasingly diagnosed posing a new diagnostic and therapeutic problem. Not all this intussusceptions require aggressive work because most of them are intussusceptions without a lead point and therefore of no clinical importance. Therefore, it is important to know the imaging characteristics that permit the distinction between them to prevent unnecessary aggressive therapeutics. Results: Side effects of the oral application of mannitol were noted in four cases (one case of vomiting and three cases of mild diarhea), no serious complication was present. The evaluable images with suffi cient distension of the bowel loops were obtained in 92 cases. Signs of activity -mucosal and submucosal enhancement of thickened bowel wall -with or without fi stulisation were found in 41 cases, non-active CD in 22 cases (including 4 cases of stenosis), ulcerative colitis in 5 cases, enteritis in one case and normal fi nding in 31 cases. Conclusion: MR enterography with 2.5 mannitol is a safe valuable imaging tool and should be used as the prime imaging modality in patients with suspected or known CD. Purpose: The purpose of this study is to evaluate the correlation between tumor blood fl ow calculated with perfusion CT and clinicopathological status of gastric cancer.

The study enrolled 30 consecutive patients who underwent surgery for advanced gastric cancer. Perfusion CT was performed with a 16-row MDCT using an intravenous injection of iodinated contrast material. Sequential dynamic scans were performed on a single level where the tumor was largest in size. These dynamic images were reconstructed in the workstation to create a functional image. The new image was analyzed to calculate tumor blood fl ow (BF, ml/min/100 g tissue), using ROI. We compared the BF in each patient and evaluated its correlation with the clinicopathological status of the gastric cancer. Results: No signifi cant correlation was found between the BF level and the tumor location, diameter, or T-stage. The BF level was higher in the cN0 group than in the cN1/2 groups, and signifi cantly higher in pStage I/II compared to pStage III/IV. Pathological examination revealed the BF level of the undifferentiated-scirrhous type, often with high-grade malignancy resulting in poor prognosis, to be signifi cantly lower than that of the differentiated-medullary type.

The BF value of the gastric cancer acquired from perfusion CT may refl ect the histopathological structure of the tumor, including tumor vascularity and volume of extracellular matrix components of the tumor. This radiological imaging procedure is a valid modality to visualize the decreased tumor blood fl ow for assessing the malignancy level of gastric cancer, especially in those with high-grade malignancy.

Evaluation Results: The tumor size was 4.9 ± 1.7 cm in diameter. The SUV of all tumors was 4.0 ± 2.5, and the MI was 6.9 ± 6.5 (50 HPF). There was a signifi cantl correlation between SUV and MI (R=0.50, P=0.011). Based on the guideline, SUV of the low-risk group (N=7) was 2.9 ± 1.4, intermediate-risk group (N=8) 2.6 ± 1.6 and low-risk group (N=10) 5.8 ± 2.8. SUV level of high-risk group was higher than that of low group and intermediate group with a statistical difference (P=0.036, 0.007, respectively). When the cut-off SUV level for high-risk group was established as 6.0, the positive predictive value and the accuracy rate was 100% and 85%, respectively. Conclusion: FDG-PET may be an appropriately quantitative modality to distinguish high-risk group with acceptable diagnostic value.

Staging of gastric cancer: CT fi ndings and correlation between lymph node size and metastatic infi ltration A. Gligorievski, K. Gjoreski, A. Karagjozov; Skopje/MK (atgl@mail.net.mk)

Purpose: The assessment of lymphatic metastases is an important factor in the staging of gastric cancer. Lymph node size has been used as one criterion for possible nodal metastasis.

In a prospective morphometric study, the regional lymph nodes from 31 gastrectomy specimens of consecutive patients with primary gastric adenocarcinoma were analyzed. The lymph nodes were counted, the largest diameter of each node was measured, and each node was analyzed for metastatic involvement by histologic examination. The frequency of metastatic involvement was calculated and correlated to lymph node size. Results: A total of 1253 lymph nodes were present in the 31 specimens examined for this study. A mean number of 40 lymph nodes (range 20-53) were found in each specimen. Of these 1253 nodes, 922 (74%) were tumor-free and 331 (26%) contained metastases. The mean diameter of the lymph nodes free of metastases was 4.1 mm, whereas that of nodes infi ltrated by metastases was 6.0 mm (p <.0001). Of the tumor-free lymph nodes, 735 (80%) were less than 5 mm in diameter, whereas 182 (55%) nodes containing metastases were less than 5 mm in diameter. Of the 10 patients without lymph node metastases, 7 had at least one node that was 10 mm or greater in diameter; similarly, 15 (71%) of the 21 patients with node metastases had at least one node that was 10 mm or greater in diameter. Conclusion: Lymph node size is not a reliable indicator for lymph node metastasis in patients withgastric cancer. Purpose: Physiological FDG uptake in the stomach is often seen, especially at the oral end. Water ingestion just before scanning would make stomach distention and thin the gastric wall, which may lead to apparent reduction of uptake in area of stomach. In this study, we assessed whether gastric distention using water ingestion suppressed physiological FDG uptake in the stomach. Methods and Materials: Forty patients who had FDG whole-body PET imaging for cancer screening followed by gastric endoscopic examination were registered in this study. All patients took 400 mL of water for hydration and were administered 185 MBq of FDG intravenously. All patients were randomly divided into two groups with or without (additional) water. With water group, 20 patients had additional 400 mL of water immediately before PET imaging. The stomach regions were classifi ed into three areas: U (upper)-area, M (middle)-area, L (lower)-area. The degree of FDG uptakes in these three gastric regions were semi-quantitatively evaluated using SUV. Results: Without water group, the mean SUVs in the U-, M-, L-areas was 2.43±0.11, 2.31±0.11 and 2.13±0.13 respectively, while in water group, 1.94±0.16, 1.84±0.16 and 1.84±0.18, respectively. With water group, the SUV in the U-and M-area were signifi cantly lower than that of without water group (P <.05). A signifi cant difference in FDG uptake was not observed among the three gastric areas in water group (P <.05). Conclusion: Additional water-intake immediately before PET imaging suppressed the physiological gastric FDG uptake. Therefore, decrease of physiological stomach accumulation with this method has a possibility of improving diagnosing in this area. Learning Objectives: To be aware of the importance of fat stranding in locating the abdominal urgent pathology. To be familiar with the differential diagnoses depending of the fat stranding location. To differentiate the benign entities that resemble life-threatening diseases. Background: CT plays a crucial role in differentiating the underlying causes of the symptoms in acute abdomen. Fat stranding is a CT sign that helps in the evaluation of patients with acute abdominal pain in emergency radiology. It is no patognomonic though it warns us where to look at. Fat stranding may arise from many causes that should be considered in the differential diagnosis. Acute conditions that cause fat stranding include appendicitis, ischemia or perforation of the bowel, cholecystitis, trauma and surgery. Imaging Findings: We have made a pictorial review showing and describing the CT imaging features of the most common abdominal urgent pathology. We try to demonstrate how fat stranding on abdominal CT can help us to identify the crucial point of the acute abdominal at fi rst sight. Once localized it, we describe the specifi c imaging fi nding that will lead us to a fi nal diagnosis. Correct non-invasive diagnosis is important because treatment approaches for these conditions range from monitoring to surgery. We show some key-facts to help us to differentiate both groups. Conclusion: Fat stranding is a useful sign to localize the underlying pathology in acute abdomen. Knowledge of CT signs accompanying it helps us to reach a fi nal diagnosis, and therefore a more accurate clinical decision.

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Evaluation Background: Bowel and mesenteric injuries are detected in 5% of blunt abdominal trauma patients at laparotomy and rarely occur isolated. Early diagnosis and treatment are critical to decrease morbidity and mortality. CT has become the primary modality for the imaging of these patients. However, radiological signs can be subtle and should be regarded as complementary to meticulous clinical assessment. Imaging Findings: CT fi ndings in bowel and mesenteric injury include the following: a. direct fi ndings of bowel injury: bowel wall disruption and oral contrast extravasation. b. direct fi ndings of mesenteric injury: intravenous contrast extravasation from mesenteric vessels. c. indirect fi ndings of bowel injury: free intraperitoneal/retroperitoneal air or fl uid. d. indirect fi ndings of mesenteric injury: diffuse bowel wall thickening, diffuse bowel wall enhancement, mesenteric infi ltration or haematoma. When indirect fi ndings of bowel or mesenteric injury are the only CT fi ndings, the need for surgical intervention is highly dependent on clinical judgment and can be necessary reassessment with CT 6-8 hours after the initial evaluation to elucidate the signifi cance on such fi ndings. Conclusion: CT has been shown to be accurate for detecting bowel and mesenteric injury caused by trauma and is useful in predicting the need for either surgical repair or conservative management.

The target sign on multidetector-row CT: Spectrum of bowel diseases R. Cianci, A. Filippone, A. Gorgoglione, M.L. Storto; Chieti/ IT (r.cianci@rad.unich.it) Learning Objectives: To understand the signifi cance of target sign as seen on contrast-enhanced multidetector-row CT (MDCT) of the abdomen. To illustrate various bowel diseases in which target sign may be observed.

The target sign is a term used to indicate stratifi cation within a thickened bowel wall that consists of three layers: a inner and outer layer of high attenuation, respectively corresponding to contrast-enhanced mucosa and muscularis propria/serosa, and an intermediate layer of decreased attenuation corresponding to submucosa. The target sign is believed to represent hyperemia in the mucosa and the muscularis propria, serosa or both and edema or infl ammation in the submucosa.

The target sign is commonly observed in idiopathic infl ammatory bowel diseases (ulcerative colitis and mostly Crohn disease) and ischemic enterocolitis; it may be present in intramural intestinal hemorrhage, infectious enterocolitis, vasculitis (Henoch-Schönlein purpura, lupus erythematosus), radiation enterocolitis and bowel edema in cirrhosis. The fi nding of stratifi ed attenuation in a thickened segment, although non specifi c, most likely represents non neoplastic disease, with the exception of the rare occurrence of this sign in infi ltrating scirrhous carcinoma of the stomach and colon. Potential pitfalls in the diagnosis are residual fl uid and oral contrast material fi lling the bowel lumen or the deposition of submucosal fat.

The target sign may be seen on contrast-enhanced MDCT scans as a non specifi c feature of non neoplastic bowel diseases. Correlation with patient clinical history and associated CT fi ndings related to the bowel wall or mesentery may allow to narrow the differential diagnosis.

Multidetector Background: ISIGO is a rare benign and self-limiting disorder, presenting with aspecifi c clinical symptoms that may mimic other acute abdominal conditions. The cause of ISIGO has been not established; it has been postulated that precipitating factors resulting in displacement of the omentum, such as sudden increase in abdominal pressure after heavy meals, overexertion, a sudden change in body position, coughing or sneezing, may cause venous stasis and thrombosis leading to omental edema and congestion, with hemorrhagic necrosis and extravasation of serosanguineous peritoneal fl uid. Imaging Findings: All typical imaging features of ISIGO are well recognizable on unenhanced CT scans; they include a well circumscribed, oval or cake-like fatty mass with heterogeneous attenuation, containing strands of soft tissue attenuation probably corresponding to fi brous bands and/or dilated thrombosed veins. The mass is usually right sided and most often located deep to the rectus abdominis muscle and anterior to the colon. It appears adherent to infl amed, thickened parietal peritoneum. There is frequently a small to moderate amount of free peritoneal fl uid. Major differential diagnoses include appendicitis, cholecystitis, diverticulitis, epiploic appendagitis and, less frequently, primary benign or malignant neoplasms or metastatic peritoneal seeding. Conclusion: To recognize MDCT fi ndings of ISIGO is important in making the correct preoperative diagnosis in patients with acute abdominal pain. It may avoid unnecessary surgical explorative intervention.

Intestinal intussusception in adults: X-ray, US, CT, and MRI fi ndings F. Sandomenico, O. Catalano, A. Nunziata, V. De Rosa, A. Petrillo, A. Siani; Naples/IT (tonikus@libero.it)

Learning Objectives: To describe the imaging appearance of gastro-intestinal intussusception with a large range of diagnostic modalities in patients with a variety of intussusception locations (gastric, jejunal, ileal, ileo-colic, appendicular, colic, and rectal), presentations (acute, chronic, transient), and causes. To make the reader aware of the clues to a diagnosis and of the imaging features of complicated intussusception. Background: Intussusception is the herniation of one segment of the gastrointestinal tract into another (proximal to the former or, more frequently, distal). In adults, intussusception usually has a leading cause and may develop at different levels with a variety of clinical presentations. We illustrate all X-ray, US, colour-Doppler, CT, and MRI fi ndings in adult intussusception of the stomach, the small bowel, the appendix, and the large bowel. We report cases of obstructing, subacute, chronic, and even transient intussusception. We highlight the clues to a diagnosis and potential pitfalls. Background: Abdominal wall is a potential source of many pathologic processes.

Most of them are secondary to localized or systemic disorders, and primary lesion is uncommon. Thus, most of abdominal wall lesion can be clues to the diagnoses of unknown or recurred underlying diseases. Ultrasonography is a valuable tool in the initial screening and follow-up study after treatment. Therefore, the chances of facing those lesions in US and the importance of recognizing them with a consideration of underlying causes are increasing more and more. Imaging Findings: In this exhibit, US fi ndings of the spectrum of diseases which are classifi ed into: 1) lesion adjacent to umbilicus; metastatic lymph node, urachal cyst, umbilical hernia, collateral vessels, 2) lesion associated with surgical incision; incisional hernia, heterotopic ossifi cation of midline incision, metastasis, 3) infl ammatory lesion; actinomycosis, abscess, necrotizing fasciitis, 4) neoplastic lesion; benign and malignant tumors, 5) others will be illustrated with CT and/or pathologic correlations. Conclusion: To carefully evaluate abdominal wall lesions is sometimes a great diagnostic clue.

Gastrointestinal stromal tumours: Imaging fi ndings with histopathological correlation S.K. Lapsia, S. Ramachandra, V. Smith, S. Ghai, S. Ghai; Stoke-on-Trent/UK (jlapsia@hotmail.com)

Learning Objectives: 1. Recognise the spectrum of imaging features of primary GISTs with histopathological correlation. 2. Discuss the differential diagnosis of GISTs. 3. Review the imaging response to imatinib therapy. Background: Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal tract arising from the interstitial cells of Cajal. These cells express a tyrosine kinase growth factor receptor KIT (CD 117), which has resulted in the advent of targeted molecular drugs such as imatinib. Imaging Findings: Computed tomography (CT) is the imaging modality of choice for the assessment of GISTs. The majority of GISTs appears as large exophytic, heterogeneous enhancing masses on CT because of internal necrosis, haemorrhage or cystic degeneration. Although, defi nitive diagnosis relies on histopathology, imaging can be suggestive of the diagnosis, and plays an important role in the detection of complications and identifi cation of metastases. Differentiation from other primary gastrointestinal tumours can often be made on the basis of these specifi c fi ndings. This exhibit will demonstrate the spectrum of imaging features of GISTs, their differential diagnosis on imaging, and their behaviour following treatment with imatinib.

In this educational exhibit, the typical imaging fi ndings of GISTs with histopathological correlation are illustrated. Differential diagnosis and response to treatment are also reviewed. The importance of imaging in helping to make the diagnosis of GISTs and in their follow-up after treatment is of increasing importance because imatinib has dramatically improved the survival rates in patients with GISTs.

Normal sonographic anatomy of the inguinal canal G. Rajeswaran, J. Lee, J. Healy; London/UK (grajeswaran@hotmail.com)

Learning Objectives: The purpose of this exhibit is to describe the sonographic anatomy of the inguinal canal using ultra-high-frequency sonographic transducers, to aid accurate assessment of disorders involving this region. Background: Disorders involving the inguinal region can often be clinically diffi cult to assess. The advent of ultra-high-frequency probes has improved our ability to image the inguinal canal. However, a good understanding of the sonographic anatomy is fi rst required to prevent misdiagnosis. Imaging Findings: In this exhibit, we will document the required sonographic technique as well as common pitfalls encountered, followed by a detailed description and illustration of the sonographic anatomy of the inguinal canal. The structures described include the superfi cial and deep inguinal rings (and their boundaries), the walls of the inguinal canal, the inguinal ligament and the contents of the inguinal canal. Conclusion: We have described the ultrasound anatomy of the inguinal canal to enable sonography of this area as a dynamic, non-invasive and inexpensive method of evaluating disorders of this region. Retroperitoneal air was not uncommon in duodenal ulcer perforation (4 cases). Renal infection was also responsible for the presence of pneumoretroperitoneum (5 cases) with or without the formation of abscesses. Pancreatitis was responsible in 7 patients for the presence of air in the form of abscess or emphysematous pancreatitis. Conclusion: Trauma is by far the most common cause of retroperitoneal air collections, the second most frequent being perforation of a hollow organ such as duodenum, ascending or descending colon. Other conditions may also produce small amounts of retroperitoneal air and they have to be taken into account for a proper diagnosis, especially in diabetics or in immunocompromised patients.

Activity Methods and Materials: Thirty-four patients with beginning or relapsed IBD underwent US baseline exam and CEUS. Features of pathological bowel segment at baseline exam were: thickness of the wall more than 3 mm, loss of the echostratifi cation and increase of the vascularization at PwDoppler. After the dynamic study with SonoVue, the degree and the pattern of the wall enhancement were evaluated. On the base of these features, the activity degree of the illness has been defi ned as: active, subactive or remittent. The ultrasound data were compared with the clinical activity index: RCP level and clinical symptoms. All the patients were followed up with ultrasound examination (baseline and CEUS) in order to evaluate the response to the therapy correlated to the clinical features (40 examinations).

In the follow-up, reduction of the thickness wall of the vascularization and of the enhancement pattern was considered remission features. Learning Objectives: To present typical appearances of peritoneal, omental and mesenteric diseases and to narrow the differential diagnosis for each morphological pattern. Background: The causes of peritoneal, mesenteric and omental diseases could be divided into four major groups: infectious, infl ammatory, neoplastic, and vascular. The morphological changes in this anatomical region can be classifi ed into three basic patterns: solid well-defi ned masses (including cystic masses), ill-defi ned irregular masses and infi ltrative processes of the mesenteric and omental fat. Procedure Details: Abdominal and pelvic MDCT was performed with oral and/or intravenous administration of contrast material. The area between the diaphragmal dome and inguinal ligament was scanned. In each patient, the homogeneity of abdominal fat, the presence, attenuation and enhancement of the intraperitoneal mass, the surface and enhancement of parietal peritoneum, and the presence of mesenteric lymphadenopathy and ascites were analyzed. Conclusion: Peritoneum, omentum and mesentery can be affected either by primary pathologic conditions, or secondary by direct extension from adjacent organs, lymphatic and hematogenic dissemination, and peritoneal seeding. On the basis of clinical fi ndings and imaging appearance, the broad differential diagnosis of diseases in this region could be signifi cantly narrowed. The possible presence of mesenteric lymphadenopathy, peritoneal thickening and/or ascites can make the fi ndings more conspicuous. Learning Objectives: To illustrate radiological manifestations of the causes of obscure GI bleeding. To aid the differential diagnosis of GI bleeding. Background: Up to 5% of patients with recurrent gastrointestinal (GI) bleeding will remain undiagnosed by standard gastroscopy and colonoscopy. Gastrointestinal (GI) hemorrhage is considered obscure when conventional investigations (esophagogastroduodenoscopy and colonoscopy) fail to detect bleeding lesions. On average, 27% of patients with obscure GI bleeding have small intestinal lesions. The causes of obscure GI bleeding include Arterio-venous vascular malformation, angiodysplasia, ectopic varices (duodenal, jejuno-ileal, colonic, and peristoma varices), small bowel lipoma, small bowel stromal tumor, cholesterol crystal emboli, aortoenteric fi stula and radiation enteritis. Diagnosing these lesions is frequently diffi cult because they tend to be inaccessible to routine endoscopy. Imaging Findings: Using multidetector-row CT scanner, well-designed barium study, and angiography, we illustrate the various radiological fi ndings of obscure GI bleeding caused by splenic artery pseudoaneurysm, ectopic varices, arteriovenous malformation, and angiodysplasia.

The cause of obscure GI bleeding can be detected in many cases by using variable imaging modality such as multislice CT, barium studies, and angiography.

Imaging features of primary extra-nodal lymphoma: A pictorial review J. Quintero, P. Puyalto, A. Mariscal, C. Roqué, I. Guasch, A. Oriol; Badalona/ES (jcquintero.germanstrias@gencat.net)

Learning Objectives: The aim of this educational exhibit is to revisit the clinical presentation, classifi cation, distribution and radiological imaging fi ndings of the rare extra-nodal involvement of lymphoma. Background: Lymphomas are malignant disorders of lymphoid tissues which are subdivided into two broad groups: Hodgkin's disease and non-Hodgkin's lymphoma. Lymphoma classically presents in lymph node sites. Extra-nodal involvement may also be due to regional spread of nodal disease or haematogenous dissemination. The classifi cation of lymphoma is complex and still debated. The stage of the disease is classifi ed according to the Ann Arbor staging system. Imaging Findings: We reviewed all of radiological reports in the last fi ve years in our institution. We selected the cases with primary extra-nodal lymphoma and they were reviewed by two radiologists who were unaware of radiological fi ndings. We encountered 48 cases of primary extra-nodal lymphoma: Thoracic: lung (7) and pleural (2); Abdominal: gastrointestinal tract (10), abdominal viscera (6), urologic and genital tract (5), peritoneum (1); Musculoskeletal: bone (3), muscle (2), skin B D E F A G and subcutaneous tissue (1); Nervous system: brain (5) and spinal cord (1); Other: salivary glands (2), breast (2) and thyroid gland (1). Conclusion: Extra-nodal manifestations of lymphoma are greatly diverse and may mimic a variety of both neoplastic and non-neoplastic conditions, depending upon the site of involvement. Familiarity with the broad spectrum of primary extra-nodal lymphoma is important for enhancing lesion detection and improving diagnostic accuracy. Multimodality imaging plays a critical role in detecting, characterising and staging the disease.

CT fi ndings of chronic ambulatory peritoneal-dialysis-related conditions T. Ichikawa, T. Hashimoto, T. Yamashita, J. Koizumi, Y. Imai; Isehara/JP (tamaki-i@mars.sannet.ne.jp)

Learning Objectives: To illustrate the CT fi ndings of sclerosing peritonitis (SP) and other conditions related to chronic ambulatory peritoneal dialysis (CAPD) Background: Sclerosing peritonitis (SP) is a rare but serious complication of CAPD. SP is characterized by thickening of the peritoneum that encloses some or all of the small intestine, which could result in bowel obstruction and necrosis. Imaging Findings: This exhibit illustrates abdominal CT fi ndings of conditions related to CAPD focusing on SP. Other conditions associated with CAPD are also discussed. We retrospectively reviewed abdominal CT of 48 patients on CAPD for more than 7 years. Findings of SP were peritoneal thickening, peritoneal calcifi cation, located fl uid collections, and small bowel abnormalities. The most serious complication of SP was associated with bowel perforation in 1 case. Other conditions such metastatic calcifi cation of soft tissue and joints due to renal osteodystrophy and vascular abnormalities such as atherosclerosis were also well depicted. In addition to axial images, we utilized opitimal multiplanar sections to visualize the entire peritoneal cavity. Conclusion: CT is an important tool in the diagnosis of SP and other conditions associated with CAPD. Knowledge of specifi c CT fi ndings of SP will lead to identifi cation of this rare complication of CAPD, and is benefi cial for differential diagnosis of peritoneal disease. Other conditions associated with CAPD are also excellently depicted on CT.

Diseases of the mesentery, omentum and peritoneum G. Learning Objectives: To review the wide range of primary and secondary pathologic conditions that affect the mesentery, omentum and peritoneum. To describe the CT fi ndings of these conditions and to present some rare processes and their specifi c imaging fi ndings. Background: The peritoneum, mesentery and omentum are important sources of primary pathologic conditions as well as common sites of secondary involvement from various primary processes. Most of these conditions are common, but few others are very rare, and one should be aware of these. CT scan is an excellent tool in detecting disease in these anatomic regions and can be specifi c in diagnosing few of these entities. Radiologists should be also aware of very rare conditions affecting these areas. 

The Purpose: The aim of our study was determination of the infl uence of muscles' volume as well as all intraorbital structures' volume for the exophtalamos extend. Methods and Materials: Forty-fi ve patients (90 orbits) were the study subjects with the clinically proved exophthalmos in whom the quantity assessment of eye ball muscles, fat tissue and eye ball was carried out using NSI application. NSI, the numerical segmentation image technique, is a new computer software that nearly automatically counts the intraorbital structures volume on the base of MRI images. All patients underwent MRI examination in 1.5 T scanner using head coil.

The infl uence of the muscles' volume on the exophthalmos degree was statistically signifi cant: in a clinical method using Hertl`s exophtalmometer r=0.357, p=0.000552 in a radiological method in comparison to the interzygomaticus line r=0.511, p=2.59221E-07. The infl uence of all structures' volume on the exophthalmos degree was, respectively, 0.441, p = 1.34334E-05; 0.492, p = 8.47986E-07. Conclusion: NSI technique is a clinically useful application providing objective data calculated individually for each orbit. It is justifi ed to use the eye muscles' volume to estimate activity of the pathological processes Graves ophtalmopathy. Determination of the exophtalamos in a radiological way is more objective than clinically.

The , and x-plan radiography to visualize the correct position of the implant. Procedure Details: The DCT scan depicts vibrant site of implant better than x-plan radiography, with lower X-ray dose compared to CT. For cochlear implants, a single x-plan by Stenvers projection can directly visualize the electrodes in the cochlea. All patients with brainstem or inferior colliculus implants underwent postoperative CT scan (12 hours) to exclude complications, and to assess correct implantation. The follow-up of these implants can be done only by x-plan radiography. Conclusion: CT and DCT scan could provide a reliable and relatively fast method to precisely determine the location of middle ear implants; we prefer DCT in regards to CT because of the lesser X-ray dose administered; a single radiography is enough to visualize and follow-up brainstem or inferior colliculus implants. Learning Objectives: To outline the specifi c questions to the radiolgist with regard to cochlear implantation. Background: Cochlear implants are intended for patients with severe to profound sensorineural hearing loss (SNHL). Successful cochlear implantation depends on a variety of factors, including an intact cochlear nerve and a surgically accessible route for electrode placement. Therefore, imaging evaluation consists a major part of the preoperative assessement. Procedure Details: Twenty-eight patients, aged from 2 to 72 years who were candidates for cochlear implants were referred for imaging evaluation. All patients had severe SNHL of various causes. High-resolution computed tomography (HRCT) scans were performed most on single-detector CT scanner using the classic protocol. MRI scans were acquired from a 1.5 and 1 Tesla scanners with an axial high-resolution two-dimensional or three-dimensional (3D) fast spin echo T2-weighted sequence or 3D gradient echo (Ciss or True FISP). Non-enhanced and enhanced T1-weighted images through the temporal bone and axial fl air images through the brain were taken as well. Twenty-four patients had both CT and MR examinations. These were reviewed based on a detailed analysis of known anatomical landmarks and variants related to the procedure. Conclusion: CT is superior ino studying the bony structures of the inner ear and middle ear cavity and the course of the fallopian canal for surgical planning, whereas MRI is superior in analyzing the soft tissues of the inner ear and the vestibulocochlear nerve. Both modalities are equally effective in depicting labyrinth malformations. 

Closed In one patient, anterior chamber was shallow. Lens presented an irregular surface in 2 patients and was dislocated in one. Hemorrhage was seen in two patients (1 vitreous (< 50%), 1 retina). 5 CTs initially read negative were read positive in the retrospective review (lamellar lacerations (LL)); in all, a tiny air bubble was recognised in the cornea or at the sclerocorneal junction. In one of them, a foreign body was recognised. Prospectively 22 fractures were diagnosed at CT, retrospectively 1 fracture was not recognised, and 1 was seen only in retrospect. Nine patients with orbital fractures had intraorbital air (5 extraconal, 2 intraconal, 2 intra and extraconal). Conclusion: CT fi ndings in globe trauma are the effect of mechanical impact.

Radiologists training signifi cantly improved CT accuracy. 

Radiological Purpose: The endoscopic surgery of the frontal sinus is confronted with two diffi culties: the nearness of noble organs and the complexity of fronto-ethmoïdal anatomy. The purpose of this work is to clarify radiological anatomy and variants of the frontal sinus and its ways of drainage and to show the importance of imaging in the investigation of this region. Methods and Materials: 100 patients presenting a sino-nasal infl ammatory disease were investigated between 2004 and 2006 (complicated acute or chronic sinusitis, mucoceles, sino nasal polyposis). They benefi ted all of a sinus endoscopic exam and a scanning of the facial massif containing an axial study and coronal, sagittal and curvilinear reconstructions in the plan of the fronto-nasal tract. Results: Imaging in these patients confi rmed diagnoses evoked clinically, permitted the study of complications, notably frontal sinusitis and the exact study of the fronto-ethmoïdal complex anatomy and its ways of drainage. Anatomical detailed CT boards and various pathological correlations are presented. Conclusion: Imaging especially when realized according to a rigorous technique is an indispensable tool in the diagnosis of complications of the frontal sinusitis and in the anatomical study before surgery. Results: CT showed a solid unilateral tumour (n=19), or bilateral (n=1), developing with the nasal cavity or paranasal sinuses and extending to the maxillary sinus (n=14), and to sphénoïd and frontal sinuses (n=5). It is associated with bone erosion (n=12) and bone condensation (n=2). MRI showed a heterogeneous and lobulated tumour (n=16), and allowed categorizing patients according to the staging proposed by Krouse: 1 case of stage1, 6 cases of stage 2, 7 cases of stage 3, and 2 cases of stage 4. Association with epidermoïde carcinoma was noted in only 1 patient. Conclusion: Inverted papilloma is a rare benign tumour of nasal cavity and paranasal sinuses. It is locally aggressive. CT and MRI assessment can accurately predict the extent of the tumour. Preoperative staging by MRI may be useful for planning an appropriate surgical approach. Other lesions represented images traps for the radiologist gathering the whole of the anatomical structures which can wrongly lend with pathology like a canal confused to a fracture.

The anatomical alternatives of the temporal bone to announce to the surgeon are not rare. They are alternatives being able to constitute an embarrassment with the initial surgical way or to predispose to surgical incidents. Their knowledge is important for the radiologist and the surgeon to guide and adjust surgical procedure.

Visualization of ocular motor cranial nerves by 3D-FIESTA F. Man, Z. Wang, Y. Jiao; Beijing/CN (daman001@163.com)

Purpose: To display the oculomotor cranial nerves by MRI and to present an update on clinical applications of dominant congenital fi brosis of extraocular muscles (CFEOM). Methods and Materials: MRI was performed in 20 volunteers without strabismus and 3 CFEOMs on 1.5 T MR unit (Twinspeed, GE). A head coil was used. 0.6 mm thick slices without interslice gap were obtained in axial plane using three dimensional fast imaging employing steady state acquisition (FIESTA) sequence without enhancement. Oculomotor nerves were observed in oblique-axial and oblique-sagittal planes acquired with MPR. Results: Both oculomotor cranial nerves (CN3) were demonstrated well in oblique-axial and oblique-sagittal planes in 19 normal subjects (95%) except one. 32 abducens (CN6) of 40 nerves (80%) were displayed in oblique-sagittal planes. 25 trochlear nerves (CN4) of 40 (62%) were showed. Different degree hypoplasia of motor nerves, especially CN6, was exhibited in CFEOMs: all CN6s were very thin, in which 1 nerve could be seen normally coursing, 1 not found, and 4 traced superiorly among which 2 coursed to ipsilateral CN3. The 4 CN3s were strikingly small and 2 normal. The onsets of 4 CN4s were shown well and 2 not. Conclusion: All ocular motor nerves can be seen in the subarachnoid cisterns by using 3D-FIESTA. This is a precondition for exploiting the diagnostic potential of MR images in CFEOMs.

Magnetic resonance ( 

Fast Field Echo sequences from the resting position to the position of maximum oral opening. We evaluated signal intensity and morphology, disc position at various degrees of oral aperture, the morphology of the treated condyle, plate integrity, the onset of parotid complications, and the length of the treated mandibular branch in comparison with the healthy side.

The follow-up examinations revealed, on the treated side, fi ve cases of anterior dislocations of the disc (25%), one of disc degeneration (5%), one parotid fi stula (5%), and one case of degenerative condylar osteoarthritis (5%).

The surgical repositioning of the condyles does not always lead to morphological restoration without late skeletal anomalies. Both trauma and surgical intervention can damage the meniscal capsulo-ligamentous containing apparatus. MR allows the identifi cation of complications due to the trauma and/or treatment, and the comparative evaluation of the condyles and joint function.

Use 

Osteonecrosis and osteomyelitis of the jaws associated with i.v. bisphosphonate therapy for multiple myeloma and metastatic bone cancer: CT fi ndings A. Lo Casto, F. Ganguzza, G. La Tona, F. Sorrentino, R. Restivo, L. Solazzo; Palermo/IT (antoniolocasto@hotmail.com)

Purpose: The i.v. bisphosphonates are widely used in metastatic bone cancer but in some patients it lead to osteonecrosis and osteomyelitis of the jaws. Panoramic radiography and CT with dedicated dental software fi ndings of 8 patients treated with i.v. bisphosphonate therapy for metastatic bone cancer are described. Methods and Materials: 8 patients (5 women and 3 men, age range 66-86 years) affected by multiple myeloma (5/8 patients) or metastatic bone cancer (3/8 patients) and treated by i.v. bisphosphonate therapy for 3 months to 1 year were submitted to panoramic radiography and CT with dedicated dental software for dental pain and jaw swelling. In 2/8 patients, a fi stula in the skin surface of the chin with purulent drainage was also present. Results: CT fi ndings in the jaws were: osteolytic area, diffuse hyperdensity of trabecular bone, bone sequestrum, thinning and erosion of cortical bone, periosteal bone reaction. In 2/8 patients, a fi stulous tract draining in the skin surface of the chin was also observed in the mandible. In 1/8 patient, only the maxilla was involved, in 5/8 patients only the mandible was involved and in 2/8 patients both jaws were involved. Conclusion: CT with dedicated dental software is useful in the detection of osteonecrosis and osteomyelitis associated with i.v. bisphosphonate therapy, allowing a complete assessment of the diseases including the localization of eventual fi stulous tract.

The modern ultrasound diagnosis (US) in the combat injuries of eyes V. Troyan, K. Slobodin; Moscow/RU (carina-c@yandex.ru)

Purpose: The improvement of clinical-and-radiation diagnosis of structural changes in eyes and retrobulbar space after combat injuries. Methods and Materials: 284 cases of radiation examination for eye injuries occurred during conduct of military operations were analyzed. The ultrasound diagnosis with the help of high-frequency probes by transorbital approach was formed. During investigations, the possibilities of color Doppler were used and eye anterior section was examined with the help of water boluses in different modifi cations. Results: US method allowed developing the classifi cation groups of eye combat injuries, the US diagnostic syndromes and the radiation examination algorithm. The US high diagnostic informative capacity was noted in differentiation of retinal detachment; vascular tunic and vitreous body; in visualization and topical diagnosis of any intraocular foreign bodies more than 1 mm in size; in diagnosis of intraocular and retrobulbar hemorrhages and their sequelae. It also appeared effective in diagnosis and prognosis of development of infl ammatory posttraumatic changes in the eye based on the analysis of ratio blood fl ow velocity in retinal central artery/orbital artery; the degree of posttraumatic subatrophy and its development; in lens dislocation and change in its transparence. US is the method of choice in cases of "hydrodynamic" rupture of sclera and orbital osteal walls during eye severe contusion and in stab wounds. Conclusion: Complex US is a universal method for evaluation of structural changes in the eye after combat injuries that can be used for screening, pathologic process verifi cation under conditions of multi-purpose institution and for dynamic follow-up of treatment results. Purpose: Compare image quality of sinonasal cavities scans obtained with standard radiation dose and 50% reduced radiation dose with a 16-detector row CT scanner.

The study includes forty patients referred to multislice CT (MSCT) scan of the sinonasal cavities for suspected chronic sinusits. Twenty patients underwent MSCT examination at standard dose using the following protocol parameters: 16 x 0.625 mm detector confi guration, 0.562:1 pitch, 150 mAs, 120 kV and 1.25 mm slice thickness. CT scan were obtained in the other twenty patients with half radiation dose by using a pitch of 1.375:1. In all patients, 1.25 mm axial and coronal images were reconstructed from raw data. All CT scans were reviewed by a neuroradiologist who evaluated, with a three-point quality scale, several anatomical structures and infl ammatory mucosal changes. The graded differences between the two protocols were evaluated using a t test.

Results: Reduced dose scans were performed with a CTDIvol of 23 mGy. No signifi cant image quality differences were observed between the two groups of patients. Conclusion: Dose-reduced MSCT helical examinations of the sinonasal cavities can be obtained using 1.375:1 pitch and 23 mGy CTDIvol without signifi cant image quality loss. The presence of fi brovascularized area at the level of the equator of the partially wrapped porous PTFE sphere is revealed in 5 patients and was associated with the reduction of SI from this zone on T2-WI. Depth of germination was 1-8 mm.

Porous PTFE does not create any artifacts that allow to differentiate surrounding orbital structures − ocular muscles, optic nerve and orbital fat.

Magnetic resonance studies seem to be the best-suited imaging modality for assessing the fi brovascular tissue progression into porous PTFE spheres after enucleation and for identifying patients in whom vascularization has failed.

Preventing FESS from turning into a mess: Role of the radiologist D. Ganeshan 1 , C. Barwick 2 , N. Purpose: The usefulness of 123I-IMP for the diagnosis of orbital malignant melanoma is well recognized, but the estimation of the uptake is sometimes diffi cult because the images acquired 24 hours after injection may be so faint that the ROI we draw becomes arbitrary. We evaluated a new semiquantitative procedure to estimate more easily and objectively the uptake of 123I-IMP in patients with orbital malignant melanoma. Methods and Materials: First, we obtained the normal MRI image of the brain, standardized by the fusion software included in Neurostat. The standard ROIs were determined from the several slices for the orbit, and then they were adjusted to the standardized SPECT image of the 123I-IMP. The uptake was calculated by VOIClassic including the Neurostat system. Twenty patients with orbital tumor were assessed. We compared the uptake of the affected side of the orbit. Retention Index was calculated with decay correction. Retention Index= (delayed ratio-early ratio)/early ratio x 100 (%). Results: It was possible to distinguish the melanoma from the other orbital tumors without the fusion image of the co-registered MR and SPECT images. When we set the cut-off level at RI≥100, sensitivity was 85.0%, specifi city was 86.7%, and accuracy was 85.7%. Conclusion: Semiquantitative parameters calculated by VOIClassic including the Neurostat system are useful and provide an objective method for the diagnosis of orbital malignant melanoma. Learning Objectives: To establish the key radiologic fi ndings to enable the differential diagnosis between craniofacial involvement of Paget disease and of fi brous dysplasia. Background: Paget disease and fi brous dysplasia are 2 bone disorders, with frequent craniofacial involvement, in which imaging studies play a very important role in orienting the diagnosis and planning appropriate surgical treatment. Fibrous dysplasia is a skeletal developmental anomaly of the bone-forming mesenchyme that usually affects young people, with craniofacial involvement in up to one third of the cases. Paget disease is a bone formation/resorption disorder that normally affects people over 40 years of age, with craniofacial involvement in up to 60% of cases. Like fi brous dysplasia, Paget disease can present different radiologic patterns in function of the stage of the disease. Imaging Findings: We reviewed 10 cases of Paget disease and fi brous dysplasia with bone involvement on craniofacial CT seen in our hospital. The key features to consider in the differential diagnosis between craniofacial involvement due to Paget disease versus fi brous dysplasia are: a) whether or not bone involvement is symmetrical, b) whether or not it crosses sutures, c) the bone pattern, and d) the presence or absence of disease in the paranasal bones.

We determined the key imaging fi ndings to enable the differential diagnosis between Paget disease and fi brous dysplasia on the basis of density, involvement, and distribution of the lesions. Learning Objectives: To understand the pleomorphic presentation of retrobulbar hematomas, occurring after cranio-facial trauma, the radiologic techniques to investigate them, and the principal features useful to achieve the differential diagnosis. Background: Retrobulbar hemorrhagic lesions can be classifi ed in two groups: intraorbital hematoma and subperiosteal hematoma. Subperiosteal hematomas represent a rare but well-defi ned clinical entity; they are more frequently seen in children, due to the loose adhesion of periostium in these patients, which can be easily detached from orbital bones by a hemorrhagic mass, with resultant proptosis and compromise of the optic nerve. Infrequently, this kind of retrobulbar hemorrage can be associated to the presence of an extradural intracranial hematoma; and this condition is known as a real diagnostic and therapeutic emergency. Diagnosis relies on computed tomography (CT) and magnetic resonance (MR). Imaging Findings: Anatomy and radiologic anatomy; classifi cation; MR and CT features; cases series. Conclusion: CT and MR allow a correct classifi cation, and provide critical information to the surgeon for mandatory treatment.

Correlation between multiplanar reconstruction sections and threedimensional CT images of the normal temporal bone N. Fujii, Y. Inui, K. Katada; Toyoake/JP Learning Objectives: To demonstrate three-dimensional CT (3D-CT) images of the whole temporal bone, the mastoid cavity, the tympanic cavity, the auditory ossicles and the inner ear. To correlate multiplanar reconstruction (MPR) sections in various angles with 3D-CT images. To identify four specifi c sections of the ossicles, the images of which are reconstructed to allow viewing of the ossicular chain. Background: Recent advances in multislice CT (MSCT) have made it possible to obtain high-resolution isotropic volume data, allowing us to generate 3D-CT images of the temporal bone, in which small structures and intricately shaped ossicles are depicted clearly. Furthermore, we have been able to reconstruct two-dimensional (2D) sections of the temporal bone, even the ossicles, from any desired direction with MPR without diffi culty. Therefore, it has become possible to recognise an object that has small and complicated structures with 2D-3D correlation. Procedure Details: MPR and 3D-CT source data from a volunteer were acquired by a 0.5-mm, 4-row MSCT system, using a unique high-resolution image reconstruction algorithm. MPR sections showed conventional axial, coronal planes and four specifi c sections of the ossicles, which we have identifi ed for the purpose of viewing the ossicular chain. Each structure has been indicated on both MPR and 3D-CT images and correlated with each other. Conclusion: High-resolution MPR and 3D-CT images with MSCT depict the complicated anatomy of the temporal bone. 2D-3D image correlation and recognition helps to deepen understanding of conventional 2D sectional anatomy, and to identify the optimal section for observing a given object. On the lower compartment, the anterior was cochlea nerve foramen which had spiral shape, and the posterior was inferior vestibular nerve foramen. The position of single foramen is uncertain, usually located on in-posterior of IAC fundus. In abnormal group, 9 ears were shown as IAC fundus disorder and foramina absent, only 1 foramen was shown in 1 ear, 2 foramina in 4 ears, 3 foramina in 2 ears, 4 foramina in 2 ears; Abnormal shape of cochlear nerve foramen was seen in 4 ears, spiral shape disappeared completely in 2 ears, small round shape was shown in 2 ears. Conclusion: Three dimensional imaging can improve the understanding and comprehension of IAC fundus. CTVE is useful in showing the normal structures and pathological changes of IAC fundus.

Establishment of normal cochlea measurements on standard HRCT images to aid diagnosis of cochlea hypolasia G. Wuxian, G. Ruozhen, C. Baoting, W. Min; Jinan/CN (grz999@yahoo.com.cn)

Purpose: To establish normal measurements of cochlea on standard position images using MPR of HRCT to aid diagnosis of cochlea hypolasia. Methods and Materials: HRCT scanning of temporal bone was undergone in 50 volunteers (100 ears). The images of all cases were postprocessed using MPR. Two standard images (position I and II) were reconstructed and 9 structures of cochlea (named A-I) were measured. Statistical analysis was done on different age groups, male and female groups, left and right groups in SPSS program. Normative data of 9 measurements were established. 9 measurements of cochlea were also done in 42 cases (78 ears 

Echo-planar diffusion-weighted MR imaging in the detection of cholesteatomas T. Kodama, T. Yano, S. Tamura; Miyazaki/JP (tkodama@med.miyazaki-u.ac.jp)

Purpose: To evaluate a single-shot echo-planar diffusion-weighted magnetic resonance imaging (MRI) (EPI-DWI) in the diagnosis of cholesteatoma in comparison with a single-shot fast advanced spin-echo sequence (FASE-DWI).

Twenty-one patients with a primary or postoperative recurrent cholesteatoma were examined by EPI-DWI and FSE-DWI in addition to standard MRI such as T1-and T2-weighted imaging. EPI-DWI was performed by using parallel imaging with a reduction factor of two. Because of its higher signalto-noise ratio (SNR), EPI-DWI was obtained with a thinner slice thickness and a higher spatial resolution than that of FASE-DWI. Image quality of EPI-and FASE-DWI was judged from: 1) contrast of the lesion, 2) image distortion and abnormal signal secondary to susceptibility artifacts, and 3) anatomical correspondence with other images. Results: A cholesteatoma was correctly identifi ed as an area of obvious hyperintense signal on EPI-DWI and FASE-DWI in 15/21 (71%) and 18/21 (86%), respectively. Among the six lesions that were missed on EPI-DWI, fi ve lesions were smaller than 5 mm. In 15 patients whose cholesteatoma was correctly diagnosed on the EPI-and FASE DWI, SNR of the cholesteatoma and cerebellum, and contrastto-noise ratio of the cholesteatoma to the cerebellum was not signifi cantly different between the both sequences. Image quality of EPI-DWI was judged inferior to that of FASE-DWI in 12 patients mainly because of susceptibility artifacts. Conclusion: To use EPI-DWI sequences for evaluating middle ear cholesteatomas, susceptibility artifact is still the problem that should be resolved despite the application of parallel imaging.

High-resolution computed tomography evaluation of congenital anomalies of the external auditory canal and middle ear A. Skorokhoda; Kyiv/UA (rdcams@svitonline.com)

Purpose: Congenital anomalies of the external auditory canal are rather common. The degree of congenital deformities runs from total atresia to hypoplasia or stenosis of the EAC, to microtia. Embriological development of the EAC and middle ear is linked so dysplasias are usually combined.

We present the experience of 36 patients examination

with external auditory canal and middle ear dysplasias from 1 to 12 years. In all cases we used high-resolution CT on Somatom Plus 4 (Siemens, Germany) in axial and coronal planes.

The study included 6 cases of bilateral atresia (1-bony atresia, 1-membranous atresia, 4-atresia of external auditory canal with ossicular deformities and hypoplastic mastoids). Unilateral atresia was found in 30 cases: 1-bony EAC atresia; 5 -EAC atresia with normal sized middle ear; 10 cases had ossicular deformities but normal mastoids, 11 unilateral atresia cases had ossicular deformities and hypoplastic mastoids, thick atresic plate and no ossicles was found in 5 cases. Small tympanic cavities were in 14 cases. Mandibular condyles were displastic in 8 unilateral cases. Stenosis of EAC occurred in 1 unilateral and 1 bilateral cases. Combined inner ear Mondini deformity was found in 1 case. Anteriorly located descending facial nerve canal was noted in 12 cases. Conclusion: High-resolution computed tomography is the most important preoperative test in patients with congenital aural atresia and evaluation of the changes in middle ear, otic capsule, ossicles, mastoids, temporo-mandibular joint, facial nerve canal for providing reconstructive and cosmetic operations. Although it has been described as a "relatively common" benign neoplasm, study of the literature reveals that the incidence is not very high. It is a slow growing, vascular lesion seen more often in middle age females. Usually it is not detected until an imaging study is performed for other reasons. Although OCA is histologically benign, it can displace intraorbital structures, and cause optic nerve compression or increased IOP. Painless, gradually progressive proptosis and visual disturbance are the main clinical signs. Imaging Findings: Ultrasound when performed will reveal a smoothly marginated round or oval, hypoechoic lesion with presence of internal fl ow with color-Doppler. Computed tomography demonstrates a hyperdense intraconal lesion, with marked homogeneous contrast enhancement. Commonly orbital bone expansion is seen. Calcifi cation is rare. In Magnetic Resonance Imaging, the lesion appears isointense to muscle on T1W1 and hyperintense on T2W1. It displaces the optic nerve without infi ltrating it. The IV administration of contrast material causes enhancement of the lesion. Conclusion: Knowledge of the radiological appearance in cases of OCA is mandatory for its correct characterization, thus, facilitating optimal treatment.

Head and Neck Background: Diffusion-weighted imaging is a new imaging modality, which has signifi cant role in the brain and, recently, in the head and neck. Procedure Details: Diffusion-weighted MR imaging was done for 132 patients with head and neck tumor using single-shot echo-planar imaging with reconstruction of apparent diffusion coeffi cient (ADC) map. Diffusion-weighted MR imaging plays a role in differentiating benign from malignant head and neck tumors, and helps to select the site for biopsy. Also, it can be used for differentiating metastatic from reactive lymph nodes and characterization of thyroid nodules. The ADC value gives an idea about cellularity of the tumor that correlates with prognosis. After treatment, it can be used for differentiating recurrent tumors from post-treatment changes. Conclusion: Diffusion-weighted MR imaging can help in discriminating malignant head and neck tumor from benign lesions,and is used for characterization of cervical lymph nodes. Also, it has a role in follow-up of head and neck cancer patients after treatment and prediction of outcome. Purpose: To report change of diffusion-weighted imaging (DWI) of malignant melanoma in head and neck after carbon-ion radiotherapy.

Eighteen patients having malignant melanoma in the head and neck regions undertook carbon-ion radiotherapy at the National Institute of Radiological Sciences, Chiba, Japan. We examined the patients using the DWIBS (diffusion-weighted imaging with background body signal suppression) method before and after the treatment. ADC (apparent diffusion coeffi cient) value was measurable in 9 of 18 cases (mean age: 65 yrs, age range: 56-78, 5 males and 4 females). We compared the ADC value obtained before the treatment with the one obtained after the treatment. Intera Achieva 1.5 T Nova Dual system (Philips Medical) was used for the examination. The EPI-based diffusion-weighted imaging sequence with SPIR fat suppression was applied at the settings of 2 b-values, namely 0 and 1000 sec/mm 2 , respectively. Results: Average ADC value for all clinical cases were 0.897×10 -3 (S.D.: 0.142×10 -3 ) at pre-treatment and 1.355×10 -3 (S.D.: 0.573×10 -3 ) at post-treatment. ADC values increased in 8 of 9 cases and decreased in 1 case. There was a signifi cant difference in ADC value between pre-and post-treatment (P < 0.028). Conclusion: DWIBS examination for malignant melanoma in the head and neck showed signifi cant increase in ADC value after carbon-ion radiotherapy. The ADC value has the possibility of becoming a criteria when we judge the effect of the carbon-ion radiotherapy in malignant melanoma. Learning Objectives: To identify those patients who will benefi t a specifi c imaging study to rule out vascular lesions in the head and neck region. To describe the radiologic fi ndings and more frequent locations of these traumatic lesions. To establish which are the optimal imaging techniques to confi rm the presence of a vascular lesion and to characterize them.

Background: Vascular lesions of the head and neck region are a clinical emergency with important morbidity and mortality, and appear frequently in polytraumatized patients who are diffi cult to evaluate. A high suspicion index is required and prompt realization of modern imaging studies is critical for an accurate and rapid diagnosis. Imaging Findings: We review the radiologic appearance of the main traumatic vascular lesions: arteriovenous fi stula, occlusion, dissection, pseudoaneurysm, and transection. We point out the locations where one should search for these lesions. We analyze the results of the different imaging techniques. Conclusion: CT angiography (CTA) and MR angiography (MRA) allow prompt and accurate diagnosis of traumatic vascular lesions, which is crucial in the prognosis of these patients and ensures their correct management. Conventional angiography remains the gold standard for the confi rmation of these lesions and enables an endovascular treatment, but is costly and not optimal as a screening technique, and is not exempt of serious neurologic complications. The use of non-invasive techniques (CTA and MRA) for the initial assessment of vascular lesions is growing rapidly. These techniques offer several advantages: they are non-invasive, less resourcedependent, and allow simultaneous evaluation of extravascular structures. 

Effi ciency of ultrasonic elastography in the differential diagnosis (metastatic or reactive) of the enlarged cervical lymphnode F. Alam, K. Naito, T. Tachikake, J. Horiguchi, H. Fukuda, H. Yasutomi, N. Hirai, K. Marukawa, K. Ito; Hiroshima/JP (falam53@yahoo.com)

Purpose: Evaluation of ultrasonic elastographic appearance of enlarged cervical lymph nodes and exploration of the diagnostic reliability in differentiating between metastatic and reactive cervical lymphadenopathy. Methods and Materials: Realtime elastography of 60 enlarged cervical lymph nodes (28 metastatic, 32 reactive) from 25 patients (16 men, 9 women; age range: 11-85 years; 14 head-neck cancer, 11 having no malignancies) was performed. All the lymph nodes were evaluated for distribution and the percentage of stiff areas. Then they were classifi ed using a 5-pattern system (1-5). Pattern 1: Stiff areas occupying the whole or almost whole lymph node (LN) with or without a thin rim of peripheral relatively soft areas. Pattern 2: Same as pattern1 with central relatively soft areas. Pattern 3: Stiff areas occupying more than 50% of the LN. Pattern 4: Stiff areas occupying not more than 50% of the LN. Pattern 5: Small stiff areas scattered into relatively soft area of the LN. The cutoff line for metastatic lesions was set between 3 and 4. Patterns 1 to 3 were considered malignant and 4 and 5 were considered reactive. Histopathological results and clinical fi ndings (including CT fi ndings) were considered as reference standard for analysis of elastographic fi ndings. Results: Sensitivity, specifi city, positive predictive value, negative predictive value and accuracy were 78.6%, 100%, 100%, 84.2% and 90%, respectively. Conclusion: Ultrasonic elastography showed excellent performance in the diagnosis of metastatic cervical lymphadenopathy. Due to high specifi city of this method, invasive procedures might be reduced when ultrasonic elastographic result is positive for lymphnode metastasis.

Gnathic bones ( Odontogenic tumors are composed of cellular constituents whose primary purpose is to form teeth or toothrelated structures (odontogenesis). Numerous lesions can affect the gnathic bones, including odontoma (compound and complex), ameloblastic fi bro-odontoma, calcifying odontogenic tumor (Pindborg tumor), odontogenic myxoma, cementoblastoma (cementoma), ameloblastoma, odontogenic keratocyst, and dentigerous cyst. The diagnosis of these processes can be tricky because of non-specifi c imaging features, atypical clinical presentation, and lack of familiarity with certain abnormalities. Imaging Findings: Radiography, the modality most often used for initial evaluation, can be helpful for detecting cortical destruction. However, CT is more sensitive than radiography for detecting calcifi ed tumor matrix and cortical destruction. CT also provides delineation of the anatomic extent of the lesion, and can guide biopsy. In addition to imaging fi ndings, patient history, physical examination and histologic analysis are required to reach the correct diagnosis.

The morphologic characteristics of odontogenic tumors and other lesions of the gnathic bones provide key diagnostic clues regarding the aggressive or non-aggressive behavior of the disease process. Awareness of the radiologic presentations of abnormalities helps formulation of the most likely diagnostic choices.

Gnathic bones ( Background: Odontogenic tumor-mimicker lesions (non-odontogenic lesions masquerading as odontogenic lesions) may further complicate diagnosis. In the gnathic bones, a group of such lesions includes Paget's disease, brown tumor, infl ammatory disease, aggressive infantile fi bromatosis, cleidocranial dysplasia, fi brous dysplasia, leukemia, multiple myeloma, maxillary sinus carcinoma, juvenile angiofi broma, and metastatic disease. Although several of these conditions share some clinical, radiologic, and pathologic characteristics, they do have very different treatments and prognoses. Imaging Findings: Although the imaging features of many lesions mimicking odontogenic tumors are non-specifi c, knowledge of the typical radiologic manifestations of odontogenic tumor-mimicker lesions often enables their differentiation from odontogenic tumors, and occasionally allows a specifi c diagnosis to be suggested. Osseous expansion, an aggressive characteristic, may occur with non-malignant conditions, such as Paget's disease. Similarly, a rim of bone sclerosis around a lesion is a non-aggressive characteristic that, in rare circumstances, is present in malignant neoplasms. Furthermore, local infl ammation is frequently associated with poorly demarcated osteolysis and periostitis, fi ndings that resemble those of a malignant tumor. Conclusion: Although aggressive lesions are commonly malignant and benign tumors are commonly non-aggressive, this is not uniformly true. Consideration of certain imaging fi ndings of a lesion within the gnathic bones can narrow the broad differential diagnosis. 

Evaluation of radiation damage to the microstructure of the parotid gland using MR microscopy T. Kan, K. Kodani, S. Fujii, T. Ogawa; Yonagoshi/JP (jpfdt645@yahoo.co.jp)

Purpose: Radiotherapy for head and neck cancer traditionally includes large parts of the parotid gland in the radiation fi eld and often leads to distressing oral complaints. The aim of this study is to elucidate the radiation damage to the microstructure of the parotid gland using MR microscopy.

This study comprised 20 normal subjects without parotid disease and 20 patients treated with radiotherapy for head and neck cancer. Mean dose to the parotid glands included in the radiation fi eld was 11.1 to 38.6 Gy (median: 22.3Gy). MR imaging was performed using a 40 mm microscopy coil before and after radiotherapy. Axial fat-suppressed T2-TSE images were obtained with a 1.5 T scanner. We assessed the radiation damage to the parotid parenchyma and duct using ImageJ (version 1.36 software program).

The thickness of the parotid duct wall in the normal group was 0.31 to 0.62 mm (mean: 0.46 mm). In irradiated patients, thickening of the duct wall was observed (0.63-1.24 mm, mean: 0.93 mm) after radiotherapy. The difference of the wall thickness was statistically signifi cant (p < 0.001). In normal subjects, reticular pattern refl ecting the microstructure in the gland parenchyma could be clearly visualized, while thickening of the reticular pattern and atrophy of the gland parenchyma were observed in the radiotherapy group. Conclusion: MR microscopy allows us to evaluate not only the volume reduction and signal intensity changes of the parotid gland, but also the microstructure of the gland parenchyma, thereby refl ecting the histopathological changes following radiotherapy.

Multi Results: On both MCTA and color Duplex imaging, carotid body paraganglioma was characterized as highly hypervascular lesions, with anteromedial dislocation of the external carotid artery in 33 cases and posterolateral dislocation of the internal jugular vein in 7 cases. The duplex spectrum in the contributing external and internal carotid arteries showed a high fl ow and low-resistance pattern. In schwannomas and neurophibromas, vessel invasion had not been identifi ed, but close ring enhancement was revealed. On CDS, tumor was revealed as hypovascular lesion with high-resistance pattern. Neurogenic sarcomas were characterized as hypervascular tumors with invasion in internal jugular vein in four cases, while the distal part of the common carotid artery and its bifurcation could not been identifi ed in three cases. In all cases, Intralesional fl ow and tumor relationship with adjacent vessels detected by CDS and SCTA correlated well with the intraoperative fi ndings. Conclusion: MCTA and CDS are an accurate diagnostic method for the precise evaluation of neck tumors. The methods provide valuable preoperative information regarding tumor vascularity and neck vessel compression or invasion.

Gnathic bones ( Imaging Findings: Conventional (anteroposterior, lateral, and oblique), intraoral dental, and panoramic radiographs remain the mainstay in the assessment of osseous lesions involving the gnathic bones. CT and MR imaging provide further characterization of the intrinsic features of lesions affecting the ganthic bones and allow determination of the extent of involvement of the dentomaxillofacial complex and paranasal sinuses. Principles of imaging interpretation include evaluation of the lesion location within the maxilla or mandible, shape, size, and rate of growth, pattern of bone destruction, demarcation, tumor matrix, septation, osseous expansion, cortical erosion, periosteal reaction, relationship of lesion to the adjacent tooth structures and sinuses, associated soft tissue mass, and marrow edema. Conclusion: Recognition of the key imaging fi ndings of non-odontogenic tumors and tumor-like lesions affecting the maxilla and mandible, combined with clinical evaluation and results from histopathology suffi ce for correct diagnosis. Establishment of defi nitive diagnosis can help the surgeon avoid undue extensive or unnecessary surgery. were pathologically proven to be pleomorphic adenomas. The wide range of imaging fi ndings will be discussed. Conclusion: All palpable tumors in this series were greater than 10 mm on presentation and most of tumors were unilateral and involved the superfi cial lobe of the parotid (over 90%). Although pleomorphic adenomas had a wide range of size, heterogeneity, and enhancement characteristics, most tumors demonstrated a capsule with circumscribed borders. Recognizing the pleomorphic adenoma may avoid unnecessary surgery. Results: After administration of SonoVue ® , malignant nodules showed absent (4/13), faint dotted (4/13) and diffuse contrast-enhancement (5/13); in this latter case inhomogeneous (4/5 cases) or homogeneous (1/5). Benign nodules showed diffuse contrast-enhancement, both homogeneous (3/5) or heterogeneous (2/5). Quantitative data confi rmed subjective fi ndings but CEUS never modifi ed precontrast analysis. Conclusion: CEUS of thyroid gland is a feasible technique but overlapping fi ndings seem to limit the potential of this technique in the characterization of thyroid nodules.

The comparative diagnostic yield of freehand versus ultrasound guided fi ne needle aspiration of thyroid nodules R. Davis, M. Rogerson, I. Britton, J. Oxtoby; Stoke-on-Trent/UK (robmdavis@hotmail.com)

Purpose: Despite the risk stratifi cation provided by ultrasound and nuclear medicine, histology is the only discriminator of benign from malignant thyroid nodules. The method of obtaining cytology locally is hybrid, both freehand and ultrasound guided. The aim of this study was to determine which is the most successful at providing an early diagnosis. Methods and Materials: One hundred and ninety nine consecutive patients undergoing thyroid fi ne needle aspiration (FNA) during a two year period (July 2004-July 2006) were included in a retrospective review. Cytology was classifi ed as: (1) diagnostic or (2) non-diagnostic by a cytologist. Freehand accounted for 29% (58/199) of samples, whilst the remaining 71% (141/199) were obtained by ultrasound guidance. Results: Diagnostic samples were obtained in 77% (154/199) of patients. This corresponds to a diagnostic yield of 62% (36/58) in the freehand FNA group compared with 84% (118/141) in the ultrasound guided FNA group. Comparison of predicted versus observed events was performed with a chi-squared statistic of 9.78 (p < 0.001). Conclusion: Obtaining cytology by an ultrasound guided method is statistically signifi cantly more successful (p < 0.001) and should be the primary diagnostic technique in avoiding a delay in diagnosis. CT scans were obtained before and after the contrast medium administration (delay of 30 and 80 sec), with a thickness of 2.5 mm, and a reconstruction interval of 1.25 mm. CT fi ndings were compared to surgical results. Results: CT examination resulted positive in 35 cases, negative in 15 cases and doubtful in 10 cases. 40/60 patients underwent surgery: surgery identifi ed 39 lesions (37 adenomas, 2 primary hyperplasia); in 2 cases surgery was negative, while in 8 cases the lesions interested an ectopic parathyroid gland. Surgery confi rmed CT evaluation in 23/35 positive cases; in 8/10 doubtful cases, surgery confi rmed the location of the lesion in 5 cases, in 2 cases the lesions resulted to be ectopic, while in 1 case surgical exploration resulted to be negative. In 9/15 cases with negative CT fi ndings, surgery identifi ed the lesion in 8 cases, while 1 case resulted to be negative. The sensitivity and specifi city values results were 78% and 25%, respectively, with a diagnostic accuracy of 73%. Conclusion: Multidetector CT is an accurate second-level diagnostic technique in the detection of a parathyroid lesion, allowing the exploration of the entire cervical and mediastinal regions.

Radiologic 60.8% of patients showed benign cytologies and 10.8% malignant disease. 2 cases (4.3%) were indeterminate (follicular proliferation). On PET studies, 54% of the lesions showed positive uptake (Suv max: 1.7-19). Since there was an uptake overlap between benign and malignant lesions, all lesions with positive uptake underwent US-FNA. Three out of 7 cases with fi ne needle aspiration and biopsy proven malignancies had negative PET studies. Nineteen benign lesions showed positive uptake (highest value Suv max: 10). In our series, the incidence of primary thyroid cancer in patients with previous history of malignancy was 26% and for breast cancer patients it was 54%. Conclusion: US guided fi ne needle aspiration is a useful method for characterisation of thyroid lesions with a positive PET result. The absence of uptake does not exclude malignancy. Patients with previous malignancies, specially breast tumours, with positive PET results have greater incidence of thyroid malignancy.

Sonographic Purpose: To evaluate pretracheal, jugular and paratracheal lymph nodes enlargement at US in patients affected by occult or chronic thyroiditis in active phase.

We selected 154 patients who underwent neck high resolution sonography and color Doppler. Patients were divided into 3 groups: A group: 64 patients (42%) suspected of chronic thyroiditis in active phase; B group: 70 patients (45%) with clinical history of thyroiditis; C group: 20 patients (13%) with positive familiarity of thyroid pathology. In addiction, we considered the thyroid hormones and antibody titers, classifying four levels of gravity: normal (I°), low high (II°), high (III°), more high (IV°). Results: A group: 27% showed antibody titers (IV°) and sonographic characteristics of cronic thyroiditis in active phase, with pretracheal (70%), jugular (59%), and paratracheal (35%) lymph nodes reactive enlargement. 15% showed antibody titers (III°) and only pretracheal (13%) and jugular (2%) lymph nodes enlargement at US. B group: all patients had antibody titers (II°-III°) and sonographics chronic thyroiditis characteristics, with pretracheal (81%), jugular (63%) e paratracheal (25%) lymph nodes lipomatous enlargements. C group: 9% was negative from clinical-strumental point of view, while 4% had antibody titers (I°-II°) and and only pretracheal (13%) and jugular (2%) lymph nodes reactive enlargement at US.

The ultrasound evidence of neck lymph nodes enlargements, especially pretracheal, appears to be a very useful US sign of subacute or chronic thyroiditis.

Colour Background: Sonography is the main imaging tool in the assessment of patients with thyroid nodules. Malignant thyroid nodules show a variety of Doppler patterns that should be known in order to prompt further evaluation (cytology). Procedure Details: Malignant nodules usually appear hypervascular, although hypervascularity is not specifi c for malignancy. Conversely, absence of vascular signal is highly predictive of benign nature. A complete vascular halo around a nodule is highly predictive of its benign nature. Absent vascular halo and intranodular vascularity are not specifi c for malignancy, but a combination of absent halo, microcalcifi cations, and intense fl ow is signifi cantly specifi c for its malignant nature (although insensitive). Spectral analysis has a limited practical value. Lymph nodes, node-to-vessel relationship, and jugular vein thrombosis can be evaluated. Lymph nodes usually demonstrate peripheral vascularization with irregular signal distribution and alternated hypervascular and hypovascular intranodular areas. Conclusion: CD and PD imaging has a signifi cant additional role in the US assessment of thyroid cancer and of metastatic cervical lymph nodes.

Troisier sign (left-sided supraclavicular metastatic lymph node): An old but still possible presentation sign of chest and abdomen tumours F. All parotid gland tumors were histologocally confi rmed: 13 pleomorphic adenomas, 7 Warthin's tumors, 2 lymphoepithelial cysts, 1 schwannoma, 1 adenoid cystic carcinoma, 1 small cell carcinoma, 1 salivary duct carcinoma with pleomorphic adenoma, and 1 myoepitheial carcinoma. We obtained axial and coronal T1-weighted, T2-weighted and Gd-T1-weighted images. We tried to evaluate prospectively tissue characterization of the parotid gland tumors and also to analyze the relationship of the tumors to the facial nerve. After the surgical resection of the tumors, we performed MR-pathologic correlation and confi rmed the relationship of the tumors to the facial nerve. Results: From the MR-pathologic correlation, we could perform tissue characterization of the tumors. This information was useful for the differentiation of parotid tumors. In all cases, except for a few patients with large tumors, primary branches of intraparotid facial nerve were clearly identifi ed. Conclusion: High-resolution MR images obtained by MR microscopy using 3 Tesla MRI is quite useful for differentiating parotid gland tumors and preoperative planning of surgical approaches for parotid gland tumors.

Preoperative localization of hyperfunctioning parathyroid glands using C-11 methionine PET: A comparison with 18 F-FDG PET and 99m Tc-MIBI scintigraphy H. Wakamatsu 1 , S. Nagamachi 1 , S. Fujita 2 , K. Kamimura 2 , R. Nishii 1 , S. Futami 1 , S. Tamura 1 ; 1 Kiyotake-cho/JP, 2 Miyakonojo/JP Purpose: Preoperative localization of hyperfunctioning parathyroid glands in patients with hyperparathyroidism (HPT) is important. Previously, we reported a direct comparison study using 99m Tc-sestamibi (MIBI), 99m Tc-tetrofosmin, and 201 Tl. In our previous study, 99m Tc-MIBI and 99m Tc-tetrofosmin were equally useful and they were more useful than 201 Tl. Recent reports have shown the usefulness of 11 Cmethionine positron emission tomography (PET), but the role of 11 C-methionine is not well known. We directly compared the detectability for localization of abnormal parathyroid glands using 11 C-methionine PET, 18 F-fl uorodeoxyglucose (FDG) PET and dual-phase 99m Tc-sestamibi (MIBI) scintigraphy to clarify the usefulness of 11 C-methionine PET. Methods and Materials: Seven patients (3 men and 4 women), 6 primary HPT and 1 secondary HPT, were evaluated. We performed 11 C-methionine PET, 18 F-FDG PET, and dual-phase 99m Tc-MIBI scintigraphy on all patients and directly compared the detectability. They were operated and confi rmed histologically. Results: In 6 patients with primary HPT (6 adenomas), 5 patients (83.3%) were correctly localized by 11 C-methionine and dual-phase 99m Tc-MIBI scintigraphy. But 18 F-FDG PET could detect only 1 of the 6 patients (16.7%). In 1 patient with secondary HPT, 11 C-methionine PET and dual-phase 99m Tc-MIBI scintigraphy could detect 2 of the 4 abnormal hyperplastic parathyroid glands (50%), but 18 F-FDG PET could not detect abnormal parathyroid glands. Conclusion: In our preliminary study, 11 C-methionine PET and dual-phase 99m Tc-MIBI scintigraphy are equally useful for localization of hyperfunctioning parathyroid glands, but 18 F-FDG PET is not satisfactory for the localization of hyperfunctioning parathyroid glands. Purpose: We study peripheral lymph (cervical, axillary and inguinal) nodes features in order to differentiate malignant adenomegalies from hypertrophic-reactive nodes. Methods and Materials: We practised high resolution ultrasonography with 7.5-13 MHz lineal probes in 100 patients (56 women and 44 men). The ages ranged from 7-78 years (mean age 51.4 years). Results: 300 nodes were observed, with 181 benign and 119 malignant nodes. 130 benign nodes (71.8%) had oval shape (Vasallo index ≥1.8) and echogenic centre. 21 benign nodes (11.6%) were oval, without central refringence. 20 nodes (11%) had kidney-like shape with echogenic centre. 98 benign nodes (54.1%) showed central arterial signal associated with intranodal vascular branching. 67 nodes (37%) showed central vascular signal alone. In 139 nodes (76.8%) there was low resistance (IR< 0.75) arterial signals and 19 nodes (10.5%) showed high resistance Doppler signals (IR ≥or 0.75). 77 malignant lymph nodes (64.7%) appeared rounded (Vasallo index < 1.8) without central echoes, heterogeneous and hypoecoic. 12 nodes (10.1%) were kidney-shaped, hypoechoic. 27 nodes (22.7%) were rounded, with eccentric echoes. 82 malignant nodes (68.9%) showed lateral vascular signals without central vascular signals; in 16 nodes (13.4%) a central vascular signal was recorded. 67 malignant nodes (56.3%) showed high resistance vascular signals. In 28 adenopathies (23.5%) the arterial signals were of low resistance. There was no Doppler signal in 13 malignant nodes (10.9%). 10 neoplastic nodes (8.4%) showed vascular intranodal branching. Conclusion: We can combine morphologic and vascular nodal features to differentiate accurately between malignant lymph nodes and hypertrophic-reactive nodes.

US fi ndings in loco-regional metastasis from malignant melanoma A. Cuñat, E. Ponce, A. Julve, M. Pina, V. Perez, E. Belloch; Valencia/ES (acunat@telefonica.net) Purpose: We describe the US fi ndings in lesions secondary to malignant melanoma. The lesions were located near the place of excision of the primary melanoma or in the fi rst lymphatic region. Methods and Materials: 10 patients were included from March '05 to March '06. The ages ranged between 47-79 years (mean age 65 years). All the patients had their malignant melanoma resected 6-24 months before the US exam. We practised high-resolution US with 7.5-13 MHz probes.

We observed 18 rounded-oval, solid lesions and 2 fl uid-fi lled nodules. 17 lesions were hypoechoic and one had muscle-like refringence. 12 (60%) lesions were located inside subcutaneous fat over the surgical scar or at a distance 20-40 mm from the scar (8 nodes). The diameter of the lesions ranged from 3-13 mm for the non-palpable nodes (12 lesions, 60%), and 6.5-81 mm for the palpable ones (8 nodes, 40%). Four lesions (20%) showed irregular vascular Doppler signals, located in the periphery of the nodes, two with arterial low-resistance spectra, one with high resistance arterial spectra and one with venous fl ow. The remaining nodules did not showed vascular signals. Conclusion: US examination of the surgical scar and fi rst lymph node station should be included in the screening for metastasis in patients with malignant melanoma excised. The non-palpable lesions are easily detected.

Venous chest port implantation in pediatric patients E. Akgul, T. : 190) and ranged between 7 and 697 days. Six (12.8%) patients died while ports were still being used. In the follow-up period, complications were encountered in 4 (8.5%) patients. In 1 patient, port was extracted because of infection in the fourth month. In another patient, incision of port pocket was resawn because of separation. In 2 patients, the needles could not be inserted into ports because the port base was turned upside down. In these patients, the ports were rotated to normal position manually. Conclusion: In pediatric patients, implantation of subcutaneous venous chest ports should be preferably placed under imaging guidance by an experienced interventional radiologist because of the higher technical success and lower complication rates.

Transarterial embolization for the treatment of benign prostatic hyperplasia: A preliminary study on technical feasibility and safety in pigs 

Sixteen large white adult intact male pigs were randomized into 2 groups: embolization (n = 8), control (n = 8). Under general anesthesia, all animals underwent selective angiography on both sides. In animals of the group embolization, embosphere (500-700 µm) was used to embolize the prostatic branches. Three months later, the animals in both groups, except one from group embolization with lameness of a hind limb, were evaluated on sexual function by breeding with adult female pigs. Sexual function of the male pigs was subjectively evaluated by assigning 0-3 points. The animals were sacrifi ced following the sex test and the prostates were removed for pathological study. Results: Technical success was obtained in all animals that received embolization; no associated complication was observed. Compared with those in the group control, the prostate size was signifi cantly reduced after embolization (p < 0.01); no difference on sexual function was noticed between the 2 groups (p > 0.05). Pathological study suggested that particles of embosphere occluded arterioles inside the prostate; partial normal gland structure nearby the occluded arterioles disappeared with glandular atrophy and infi ltration of lymphocytes. Conclusion: Transarterial embolization of the prostate is technically feasible and safe in the healthy intact pigs. The embolization may reduce the size of the prostate without compromising the normal sexual function.

Analysis of factors related to restenosis after percutaneous angioplasty for native AVF stenosis in patients of hemodialysis J. Jang 1 , Y. Kim 1 , S. Yang 2 , D. or ≥5year) , 4)duration of AVF (< 5year or ≥5year), 5) hypertension, 6) smoking, 7)diabetes mellitus, 8) type of AVF, 9) location of stenosis, 10) degree of stenosis (< 90% or ≥90%), 11) length of stenosis (< 1 cm or ≥1 cm), 12)degree of dilatation (< 90% or≥90%), 13) thrombus, 14) use of stent, and 15) type of balloon (conventional balloon or cutting balloon). Results: There are fi ve factors related to restenosis after percutaneous angioplasty for native AVF stenosis in patients of hemodialysis patency, which are: 1) duration of AVF, 2) use of stent, 3) type of AVF, 4)location of stenosis, and 5) length of stenosis. Longer duration of AVF and use of stent in the treatment of native AVF stenosis demonstrated higher patency rate. Also, cephalic arch of AVF, brachio-cephalic stenosis, and longer length of stenosis were demonstrated higher patency rate. Conclusion: Factors related to restenosis after percutaneous angioplasty for native AVF stenosis in patients of hemodialysis were included duration of AVF, location of stenosis, use of stent, length of stenosis.

Budd ) ). Advantages/disadvantages of each will be outlined. Procedure Details: Based on a large experience of over 200 optional fi lter placements, technical issues with regard to placement of optional fi lters and complications encountered will be discussed. Issues with regard to anticoagulation will also be discussed. Conclusion: Optional fi lters are now the fi lters of choice for IVC fi ltration. Retrieval intervals differ between fi lter types, making the choice of fi lter important if retrieval is planned.

Continuous regional arterial infusion therapy for acute severe pancreatitis: Between cumulative dosage of intraarterial administrated drug for the early stage and outcomes of patients Purpose: To evaluate the correlation between cumulative dose of intraarterial administrated drug for the early stage of acute severe pancreatitis and outcomes of patients.

Thirty-fi ve patients with acute severe pancreatitis have undergone on initiation of continuous regional arterial infusion (CRAI) protease inhibitor, nafamostat mesilate, or gabexate mesilate, and antibiotics, IPM/CS, and intravenous administration of those. We retrospectively reviewed the day after disease onset, cumulative dose of intraarterial, and intravenous administrated these drugs at that time. Cumulative intraarterial administrated doses, intravenous administrated, and total administrated doses were calculated. These factors were compared with outcomes that included mortality rate, periods of admission of the hospital and the intensive care unit (ICU), periods that individual laboratory indexes indicated abnormal level. Spearman rank correlation was used for statistical analysis. Results: Each CRAI was started within 72 hours after the onset on thirty-three patients (91%). The mortality rate was 2.4%. Cumulative intraarterial administrated doses of nafamostat mesilate for the early stage had signifi cant correlation with normalization of CRP (p=.033) and periods of admission of ICU (p=.035). Cumulative intraarterial administrated doses of IPM/CS for the early stage had signifi cant correlation with normalization of CRP (p=.042). There was no correlation between other parameters and outcomes. Conclusion: These results suggest that increased dosage of intraarterial administration of nafamostat mesilate, and IPM/Cs at the early stage may reduce the period of high risked condition of acute severe pancreatitis. Purpose: TIPS with bare-stents in patients with Budd-Chiari syndrome (BCS) has a very high incidence of shunt dysfunction (stenosis and occlusion) and the placement of 10 mm stents have a high incidence (43% according to literature) of encephalopathy. We assessed the medium-term response after placement of 8 mm PTFE-covered stents.

In 2005, 9 patients (6 Child-Pugh B, 3 C) underwent TIPS with PTFE-covered stents (VIATORR, Gore, USA, 8 mm in diameter). Long-term anticoagulation therapy was promptly instituted. 5 patients had a myeloproliferative disorder, 1 genetic thrombophilia, 3 with unknown etiology. 7 patients had ascites, non-responding to diuretic therapy, 1 had bleeding due to portal hypertension, 1 had hepatorenal syndrome. HVPG before and after the procedure was measured. All patients underwent color-Doppler and laboratory exams after 48 hours and 1, 3, 6 months. After 6 months an angiography was performed. Results: In 9 procedures, 19 stents were placed. In 4 patients, a transcaval puncture was needed. HVPG reduced from 24+6 mmHg to 11+2 mmHg (p < 0.001). After a medium follow-up of 15 months, 8 patients are alive, 1 dead 3 days after the emergency TIPS procedure. 2/8 patients had an early occlusion, resolved with thrombolytic therapy. 7/8 shunts are still open at color-Doppler and angiographic study; all these patients had clinical and biochemical improvement. Only 2 patients (22%) developed a transitory encephalopathy. Conclusion: TIPS with 8 mm PTFE-covered stents obtained a good technical, clinical and hemodynamic success, at a medium term follow-up, with a lower incidence of transitory encephalopathy compared to 10 mm stents. There was no statistical difference in the clinical tumor response between the two groups. There was also no statistical difference in overall survival rates (P=.7770) between the two groups. Conclusion: Arterial infusion chemotherapy may be suitable for oral cancer and there was no different effi cacy between carboplatin and cisplatin regimens.

Bilateral vertebral artery aspiration to enhance retrieval of basilar artery embolism T.E. Mayer; Munich/ DE (t.e.mayer@med.uni-muenchen.de) Purpose: Intra-arterial fi brinolysis has lowered the death rate in patients with brobasilar thrombosis, but recanalisation failures, the time-consuming procedure itself, and haemorrhagic complications are still major limitations of this therapy. Therefore, a variety of retrievers are now under investigation, but still not satisfactory, since recanalizazion rates by the retrievers alone only reach 50%. Therefore, we evaluated a novel mechanical recanalisation technique -remote bilateral simultaneous vertebral thromboaspiration -to enhance the effect of retrievers in distal basilar artery embolism. Methods and Materials: Ten patients with acute basilar artery embolism were evaluated. They were treated with bilateral or in case of occlusion or hypoplasia of the contralateral vertebral artery (VA) unilateral proximal thromboaspiration during the use of different retrievers or even without the use of a retriever. Results: Complete recanalisation of the basilar artery was achieved in all cases.

No procedure-related complications were seen. Eight patients survived. The clinical outcome will be reported.

Conclusion: This small pilot study showed that remote thromboaspiration in distal basilar artery embolism is safe. It can be successful alone, and might be useful in combination with mechanical retriever devices. Larger and randomized studies are needed.

Percutaneous thrombin treatment of pseudoaneurysms in different arterial territories: Pictorial review A. Lüttich, J. Perendreu, J. Falco, J. Fortuño, J. Branera, P. Bermudez;

Learning Objectives: To review and illustrate percutaneous use of thrombin in the treatment of pseudoaneurysms in different arterial territories. Background and Procedure Details: We illustrate our experience in the percutaneous thrombin treatment of pseudoaneurysm with a review of all cases treated in our centre with this method. Most of the patients had pseudoaneurysms located in the femoral artery, humeral artery, tibial anterior artery, and splenic artery. We include also one case of an aortic endoleak post-endoluminal treatment treated with percutaneous thrombin injection. We show angiographic, ultrasonographic and CT images before, during, and post-procedure. Conclusion: Percutaneous thrombin injection to treat pseudoaneurysms is effective, fast and safe, and currently the treatment of choice in most of these cases.

Radiological treatment of venous stenoses after "piggy-back" technique liver transplantation ( Purpose: To describe a new approach to transjugular intrahepatic portal shunt (TIPS) using percutaneous transhepatic-transjugular technique in patients with portal hypertension, whose hepatic venous anatomy was unsuitable for the standard procedure. Methods and Materials: Portocaval shunts were created using a single percutaneous transhepatic needle pass in 5 patients. Under sonographic guidance, we identifi ed on a single plane the left or right portal vein or one of their fi rst branches and its correspondent aligned left or right hepatic vein. Both vessels were then punctured with a 20-gauge, 15-20 cm Chiba needle. A 0.021 inch guidewire was advanced through the needle into the inferior vena cava, then the needle was removed and a 5 Fr sheath was placed over the guidewire into the IVC. Subsequently, a 0.035 inch hydrophilic guidewire was snared into the superior vena cava and withdrawn through the transjugular sheath. The rest of the procedure was completed in the standard fashion.

The portocaval shunts were successful in all patients. There were no major complications during the procedures. One patient underwent OLT 1 month later. In 3 patients, the shunts were patent at 6-12 month follow-up. One patient died due to liver failure 1 month after the procedure. Conclusion: Direct portocaval shunt creation using sonographic single transhepatic needle pass is a good alternative when standard procedures are diffi cult or impossible due to inadequate venous anatomy or abnormal anatomic relationship between the portal vein branches and hepatic veins.

Early Purpose: Severe symptomatic lower limb swelling is a recognised complication of compression or invasion of the IVC by intra-abdominal malignancy. Symptomatic relief of symptoms by IVC stenting has been described as an effective means of palliation. However, there has been a reluctance to place stents across the origin of the renal veins due to the possibility of compromising renal function by a suggested reduction in renal blood fl ow. We analyse our experience with trans-renal IVC stenting and determine if there is a deleterious effect on renal function.

We review 6 patients with intra-abdominal malignancy and associated symptomatic lower limb oedema that had compression of the IVC by nodes or tumour mass. Diagnosis was made using contrast-enhanced CT or gadolinium-enhanced MRI. All 6 patients had disease involving the IVC adjacent to the renal veins. Using standard techniques, self-expanding stents were used to traverse the stenosis. All patients were monitored post-procedure with ultrasound to establish patency and regular serum creatinine levels to ensure the renal function did not deteriorate. Results: There was a signifi cant symptomatic improvement in leg swelling following stenting in all of the treated patients. Follow-up imaging demonstrated no delay in renal contrast enhancement. There was no signifi cant increase in serum creatinine levels. Conclusion: IVC stenting for the treatment of lower limb swelling due to malignancy is an effective palliative method of reducing symptomatic lower limb oedema due to intra-abdominal malignancy and can probably be safely carried out without concern for renal function compromise. Further studies are warranted. Results: Technical success was obtained in all 15 patients; in control group, technical success rate was 86%. Coil embolization of collaterals was needed in 4 (26%) of 15 patients, which were signifi cantly lower than that in control group (47%) (P < 0.05). Mean amount of sclerosant used was 15.0 ml, and was signifi cantly lesser than in control group (21.7 ml) (p < 0.05). One patient showed transient ascites for a few days after treatment, but no major complications were encountered.

The selective obliteration technique using a coaxial balloon catheter system would reduce the necessity of coil embolization procedure of abundant collateral veins, and can also reduce the amount of sclerosant. This catheter system can simplify the technique for the treatment of gastric varices.

The For the sclerosing therapy, used 3%-ed solution of thrombovar taken into account the calculations 10% from the volume of cystic content, which developed total contact with epithelial integument of cyst and caused an aseptic infl ammation of cyst walls. Some patients after interventional radiology treatment were prescribed slight forms of antihypertensional medicines according to individual. Results: Among 206 patients, recovery with stable course of arterial hypertension was reached in 115 cases (56%). Improvement has been observed in 85 cases (41.5%). In 6 (2.5%) cases, this treatment turned out to be ineffective.

Review of intra-arterial thrombolysis as a causative treatment of hyperacute cerebral ischemic stroke C. Iosif, M. Papathanasiou, A. Gouliamos; Athens/GR (christinaiosif@yahoo.gr)

Learning Objectives: To review the current imaging and interventional protocols, the indications and requirements for the performance of intra-arterial thrombolysis as a causative treatment of hyperacute ischemic stroke. To describe the methodology and results worldwide of the last 15 years. To discuss the conventions and ideal conditions of function of the stroke units in accordance with the international experience of stroke units of excellence on the fi eld. Background: Cerebral ischemic stroke is the 3 rd leading cause of death and the 1 st cause of disability in the developed countries (Europe 650.000 deaths/year, EUSI 2003) with a heavy fi nancial and social cost. The establishment of an effective treatment is a very important medical and social issue. Procedure Details: Intraarterial thrombolysis is effective when there is still viable brain tissue. Patient selection is based on the therapeutic window since the symptoms onset, on the lack of clinical and imaging exclusion criteria and on the imaging confi rmation of occlusion of cerebral artery. The imaging protocols with CT-CT perfusion mad MR diffusion-perfusion are discussed, as well as the modifi cation of the time window according to the imaging fi ndings. The therapeutic approach is either intraarterial, with the use of thrombolytic medicine, either combined with intravenous infusion (i.v. glucoprotein inhibitor ΙΙb/IIIa). The recanalisation rate is up to 70% considering the anterior circulation. Major complication is hemorrhagic transformation. Conclusion: Intraarterial thrombolysis when performed in specialized centers is an effective etiological treatment of ischemic stroke and has a low complication rate when the inclusion criteria are kept.

Effects of continuous regional arterial infusion therapy for acute severe pancreatitis: Correlation of pre-treatment disease severity and outcomes of patients Purpose: To assess the correlation between severity parameters on initiation of continuous regional arterial infusion (CRAI) and outcomes of patients. Methods and Materials: Thirty-fi ve patients with acute severe pancreatitis have undergone CRAI and intravenous administration of protease inhibitor and antibiotics. We reviewed severity parameters in these patients that included pre-treatment APACH-II score, CT severity index, laboratory indexes and the periods between disease onset and CRAI. These factors were compared with outcomes that included mortality rate, periods of admission of the hospital and the intensive care unit (ICU), periods that individual laboratory indexes indicated abnormal level. Spearman rank correlation was used for statistical analysis. Results: Thirty-three patients (91%) had undergone CRAI within 72 hours after the onset. Among all patients, APACH-II score was 10.4 ± 4.8 (mean ± SD), CT severity index was 5.4 ± 1.9. Despite disease severity, the mortality rate was extremely low (2.4%). There was no correlation between parameters of disease severity and other outcomes. Conclusion: These results suggest that disease severity may not directly refl ect outcomes of patients when CRAI is performed in early stage of acute pancreatitis.

Biomechanical infl uences for intravascular stent fractures R. Suri, E. Sprague, D. Marton; San Antonio, TX/US (suri@uthscsa.edu)

Learning Objectives: 1. To understand the signifi cance of stent fractures. 2. To evaluate the individual and synergistic role of vessel deformation, biological properties and biochemical factors that could play role in the disruption of the long term integrity of implanted intravascular stents. Background: Though percutaneous interventional treatment of stenotic vascular disease has been revolutionized with stent placement, SIROCCO trials and recent studies are reporting increasing incidence of stent fractures. The etiology and incidence of stent fractures is still unclear. Imaging Findings: 1. Incidence and clinical signifi cance of intravascular stent fractures. 2. Arterial deformation due to respiration and motion as an implicating factor for stent fractures. 3. Physical and chemical factors (including ion leaching) and biological factors (including infl ammation) at the stent surface which could precipitate stent corrosion. 4. Role of scanning electron microscopy (SEM), atomic force microscopy (AFM) and Secondary Ion mass spectroscopy (SIMS) in the in vitro evaluation of the stent surface. Conclusion: Various biological, chemical, physical and dynamic factors may play a potential role either alone or synergistically on the integrity of intravascular stents. This exhibit aims to evaluate these individual causative factors for stent fractures and to demonstrate the potential role of in vitro evaluation of the stent surface in predicting corrosion and stent fractures.

Acceleration of primary liver tumor growth rate in embolized hepatic lobe after portal vein embolization S. Hayashi, Y. Baba, R. Higashi, T. Yoneyama, M. Nakajo; Kagoshima-shi/JP (hayashi@m.kufm.kagoshima-u.ac.jp)

Purpose: Portal vein embolization (PVE) is now widely accepted as a useful preoperative procedure in selected patients undergoing major hepatic resection. The purpose of this study was to retrospectively evaluate the effects of PVE on the growth of liver tumors in the embolized lobe.

We studied 8 patients (aged 48-79 years, mean age 70 years), of whom 6 had hepatocellular carcinoma (HCC) and 2 had cholangiocellular carcinoma (CCC) primary liver tumors. PVE was performed for each segmental portal branch using fl uoroscopy. The growth rates of the tumors in the embolized lobe and non-embolized liver parenchyma were calculated using the CT volume values at the time of tumor identifi cation, and before and after PVE. Results: The mean tumor growth rate was 1.59±2.13 cm 3 /day before PVE and 3.11±3.06 cm 3 /day after PVE (p=0.011). The rate of tumor growth acceleration ranged from 1.50 to 7.62 (3.58±2.55) in the 6 HCCs and from 1.04 to 1.26 in the 2 CCCs. There was no apparent correlation between the tumor growth rate after PVE and the growth rate of non-embolized liver parenchyma (6.53±3.68 cm 3 /day).

These results suggest that the rate of liver tumor growth in an embolized lobe accelerates after PVE, especially in cases with HCCs; thus, caution

is required. Transcatheter arterial chemoembolization for an HCC before PVE may be a reasonable option to suppress the tumor growth.

Therapeutic Purpose: To study the role of therapeutic arterial embolization in the management of post-traumatic epistaxis. Methods and Materials: 16 patients with recurrent massive epistaxis (more than 100 ml) following trauma who were referred to our department are included in our study. All the patients did not respond to conventional therapy. Each patient had exploratory angiography, which included the study of the internal (ICA) and external carotid arteries (ECA) on both sides with selective injections in the branches of the ECA. The fi ndings were classifi ed as 1. Active bleeding 2. Pseudoaneurysm and 3. Others. The abnormal vessels were embolized. Results: 12 of the patients had abnormalities in the internal maxillary artery. Of these, three patients showed active bleeding into the ethmoidal sinuses. Other nine showed pseudoaneurysms in the distal branch closely related to a sinus. In all these cases, the vessel was embolized with PVA particles. One patient had active bleeding from the ophthalmic artery since the external carotid artery was ligated at an other center and could not be embolized. In another patient, bleeding was from a pseudoaneurysm arising from the internal carotid artery, which was embolized by occluding the ICA. In one patient, the angiogram was normal and both the internal maxillary arteries were embolized with Gelfoam. None of the embolized patients had recurrent epistaxis. Conclusion: Exploratory angiography and therapeutic embolization is an excellent modality in the control of post-traumatic epistaxis.

Infrapopliteal Purpose: To study the feasibility of infrapopliteal percutaneous transluminal angioplasty (PTA) and to review the outcome of 125 consecutive infrapopliteal PTA procedures and evolve guidelines for patient selection, procedure and post procedural care.

Patients with ulcer or gangrene were excluded from the study. The indication for PTA was rest pain in 105 and intermittent claudication in 20. All the patients were diabetics and 75 of them were smokers. The patients were selected for PTA when distal run off in at least one vessel was good. All the patients were on Ticlopidine 250 mg BD or Clopidogrel 75 mg OD for at least 48 hours prior to the procedure and it was continued for 6 months post procedure. Intravenous heparin was given for 24 hours post procedure. Results: There was no technical failure. All the limbs showed clinical improvement in pain by 24 hrs and this improvement was maintained at 6 months in 115 (92%). The actual limb salvage rate at 1 year for 105 patients with critical limb ischemia was 90%. Conclusion: Infrapopliteal PTA is feasible and safe. Appropriate patient selection, premedication and wound-care are important for good results. (n=37), gelfoam (n=2) and coil (n=1), but coil and gelfoam were not used alone. The number and name of each emoblized artery during BAE were recorded in addition to the number of BAEs for each patient. Cessation and recurrence of hemoptysis following BAE were also documented.

The causes for hemoptysis in 21 patients were: pulmonary tuberculosis (n=16), anthracofi brosis (n=2), bronchiectasis (n=2) and lung cancer (n=1). Embolized arteries included bronchial (n=55), intercostals (n=25), internal mammary (n=5), inferior phrenic (n=4), subscapular (n=1), lateral thoracic (n=2) arteries and costocervical trunk off the subclavian artery (n=2) in addition to some minor branches off the subclavian (n=7). Those arteries off the subclavian arteries were usually affected when there was pleural thickening in the apical area. Cessation of hemoptysis was achieved with a single BAE (n=24, 61.5%), whereas either continuing or recurring hemoptysis was observed after 15 BAEs. However, after repeated BAEs, all hemoptysis stopped. Conclusion: The cessation of hemoptysis was achieved by BAE in all cases, although some were achieved by repeated BAEs. For a successful BAE, it is important to understand the knowledge of various arteries causing hemoptysis. Purpose: To evaluate the effi cacy and safety of a hybrid treatment for severe deep-venous thrombosis by combining clot aspiration, mechanical thrombectomy, and local fi brinolytic therapy. Methods and Materials: Within a period of 5 years, 45 patients with severe deep venous thrombosis were treated with hybrid interventional procedures. After insertion of a temporary vena cava fi lter, thrombo-aspiration with a PTCA guiding catheter and/or mechanical thrombectomy with OASIS or modifi ed rotating pigtail catheter system were performed. Additionally, continuous local fi brinolytic therapy and balloon PTA/stenting were performed, if needed. The primary endpoint was venographic fi ndings of thrombus extraction. Systemic thrombolysis and anticoagulation therapy followed. Results: Trans-femoral interventional radiological therapy was achieved in 42 patients. The approach was ipsi-lateral in 22 cases and contra-lateral in 20 cases. Interventional techniques were as follows: manual clot aspiration 37,OASIS thrombectomy 13, mechanical thrombus fragmentation using a modifi ed pigtail catheter 3, balloon PTA 3, stenting 4, and continuous local catheter fi brinolytic therapy 16. Successful venographic recanalization was achieved in 37 of 42 patients. A temporary vena cava fi lter was easily removed 9.2 days after the insertion in 37 patients. Total dose of urokinase was 3,440,000I.U./6 days. Complications: haemo-thorax 1, retroperitoneal hematoma 1, and puncture site hematoma 3.

Hybrid interventional treatment appears to be a rapid and safe improvement in patients with deep-venous thrombosis. This hybrid treatment may be a therapeutic option in patients presenting severe deep-venous thrombosis.

Partial 

Background: For hypersplenism, portal hypertension, or hematologic disorders, PSE is often performed. However, severe complications such as splenic abscess, gastritis, or pancreatitis may limit the indication. In order to reduce these risks, two different methods of PSE were introduced using the MRXO. Procedure Details: Prior to PSE, diffusion-weighted images (DWI) including blood oxygenation level dependent (BOLD) images were performed for the splenic volumetry using a 1.5 Tesla MR machine. After the celiac and superior mesenteric arteriography, splenic arterio (SpA) CT was obtained to evaluate the splenic or pancreatic branches. Segmental PSE (s-PSE) using microcoils with gelfoam particles or Lp-NBCA, or peripheral PSE (p-PSE) using microspheres were performed following the exclusion of gastric and pancreatic branches. Splenic ischemic range was evaluated on BOLD images during the procedures and pursued up to 60-70%. Conclusion: A control splenic volumetry was semiautomatically obtained using a workstation based on DWI. SpA-CT allowed easy recognition of gastric and pancreatic branches and the exclusion before PSE. The ischemic foci shown on BOLD images immediately after the procedures corresponded well to the non-enhanced area on CT one week later. Although p-PSE produced multifocal infarctions and may theoretically disturb abscess formation, the volumetry of ischemic (infracted) tissue is better evaluated on s-PSE than p-PSE. The MRXO is useful for safe and effective PSE.

Carcinoids Background: Carcinoid tumours are one of the more frequently encountered endocrine tumours of the gastrointestinal tract, and can have a wide spectrum of presentations. The radiological appearance of carcinoids varies depending on their size, location, and on their variable biological behaviour, and can often be very diffi cult to diagnose. Imaging Findings: We retrospectively reviewed the imaging of histologically proven carcinoid tumours in our institutions for the last fi ve years. The clinical symptoms are varied and the diagnosis can be made biochemically or histologically. Imaging is playing an ever-increasing role not only just in the diagnosis, but also in the treatment using percutaneous techniques. Cases highlighted include carcinoids presenting as acute gastrointestinal bleeding and multifocal intra-abdominal masses. Endovascular treatment appearances such as transarterial chemoembolisation (TACE) with CT correlation pre-and post-procedure are also presented. Conclusion: Carcinoid tumours can have variable and unusual clinical and imaging presentations. Familiarity with their appearance on imaging can be helpful for radiologists to avoid misdiagnosis and for initiation of proper treatment. Interventional procedures have an increasing role in both diagnosis and treatment, leading not only to effective control of symptoms, but may also help prevent potentially dangerous complications.

Purpose: To assess the clinical effects of transcatheter arterial chemoembolization (TACE) under corresponding portal vein occlusion (TACE-PVO) for patients with hepatocellular carcinoma (HCC) and marked arterio-portal shunts (AP-shunts).

The study subjects were 14 patients with unresectable HCC and marked AP-shunts who underwent embolization of the AP-shunts with coils and/or gelatin sponge particles (group A: n=7) or TACE-PVO (group B: n=7). Our primary aim was to assess the effi cacy of TACE-PVO for patients with unresectable HCC and marked AP-shunts, and our secondary aim was to assess differences in therapeutic effects between groups A and B. Results: No major complication resulting directly from the procedures was seen in either group. There was also no inter-group difference in the effectiveness of treatment for the AP-shunts. Subsequent TACE therapy was possible in 2 patients of group A and 6 of group B after treatment of the AP-shunts. A favorable response in terms of tumor necrosis exceeding 50% was seen in 28.6% of patients in group A, and in 100% of patients in group B (including 4 cases of complete tumor necrosis). The 1-and 2-year survival rates in group A were 28.6% and 0%, respectively, whereas the 1-, 2-and 3-year survival rates in group B were 85.7%, 85.7% and 42.9%, respectively. There was signifi cant difference (p=.038) of survival rates between group A and B.

The TACE-PVO method may be a safe and useful therapy for selected patients with unresectable HCC and marked AP-shunts.

Exploratory Methods and Materials: Exploratory digital subtraction angiography was performed in 250 patients presenting with hemoptysis. The study included aortography, bronchial, intercostal, and subclavian angiography with selective injection into internal mammary arteries. Embolization of all abnormal vessels was performed with PVA sponge particles of 500-700 microns and 700-1000 microns. The recurrence of haemoptysis was assessed at 24 hrs, 1 month and 1 year. All the patients had chest radiograph prior to angiography. HRCT of the lungs was performed if the radiograph was normal. Bronchoscopy was performed when the radiograph did not show a defi nite evidence of tuberculosis. Results: Single vessel was abnormal in 53% and multiple vessels in 47%. On an average, 3.5 vessels were abnormal in the latter group with a range of 2-6 vessels. The commonest vessel to be involved was the bronchial artery (78%) followed by internal mammary (38%), the intercostal artery (27%) and the thyrocervical trunk (17%). 25 (10%) cases had recurrence of haemoptysis in the fi rst 24 hrs, 22 (8.8%) of these patients had an additional vessel, which was missed initially. 3% of the patients had normal arteriography and continued to have haemoptysis. An overall recurrence of 6% was seen at 1 year follow-up.

If an area of pathology has multi-vessel involvement, embolization of all the vessels with 500-700-1000 microns PVA particles gives good long term results.

Embolic Learning Objectives: 1. Compare and contrast various embolic protection devices. 2. Pictorially depict and classify procedural adverse events due to embolic protection devices during carotid interventions. 3. Understand techniques to avoid and appropriately manage these adverse events. Background: Outfl ow embolic protection devices are used during carotid interventions, though their role is still controversial. They enjoy the benefi t of preventing neuroembolic complications; however, the use of these devices increases procedural time with associated increased risk of adverse events. Imaging Findings: Procedural adverse events specifi c to embolic protection devices may be classifi ed into: (I) minor adverse events (resolve with appropriate management), and (II) major adverse events (persist despite appropriate management and cause morbidity). Minor adverse events may occur during device deployment (technical failure, or use of adjunctive procedures), stent/PTA (device migration, pseudo-occlusion, arterial spasm responsive to nitroglycerine, transient neurological defi cits), or device retrieval. Major adverse events maybe related to intraprocedural events (proximal device migration, arterial spasm refractory to nitroglycerine, fl ow-limiting dissection, persistent neurological defi cits) or device retrieval. Knowledge of techniques to avoid and appropriately manage these adverse events is essential.

The aim of this exhibit is to compare and contrast embolic protection devices, clarify their role with evidence based literature, classify device related adverse events, and present a pictorial essay of these potential complications with their appropriate management. Preoperative diagnosis was performed through spiral computed tomography and in some cases digital subtraction angiography. Results: All patients underwent endovascular repair using straight-tube commercial stentgrafts -Talent (64), Zenith (17) and Gore (1). Mean follow-up was 34 months (8-84 months). Technically successful implantation was achieved in 81 patients. On patient with a type III dissection required a hybrid procedure because of the continued growth of his aneurysm. Two late migrations were observed on follow-up, which required additional intervention. Seventeen endoleaks (20.7%) were observed of which 12 (46.2%) were present in dissections on the base of retrograde fl ow into the false lumen. Conclusion: There is much enthusiasm for the use of endovascular devices, especially for the treatment of thoracic aneurysms; for it may indeed hold the potential for the greatest patient benefi t as conventional open surgical repair continues to offer serious morbidity and mortality rates.

Preliminary Recently, some percutaneous devices have been developed to treat mitral valve insuffi ciency. The design of these devices is undergoing and will be based on non invasive imaging (i.e. CT and/or MRI). 64-slice CT offers extremely high spatial resolution in cardiac imaging and can be platform both for the design of these devices and for the pre-interventional assessment of the individual patient. Imaging Findings: This exhibit will provide a anatomical and pathophysiological overview of mitral valve insuffi ciency as well as a pictorial essay of mitral valve disease as seen on CT. The percutaneous devices and the technique used for the treatment will be shown and described. The role of CT in the geometrical assessment of mitral valve and in the the planning of the percutaneous procedure will be exploited. Conclusion: Percutaneous mitral valve repair is becoming a new experimental fi eld in cardiology and new devices are under development. CT can provide anatomical information extremely useful for the planning of the procedure. This information is the benchmark for the design and the sizing of the devices for the individual patients. 

We anticipated that TearLeader stent placement is more comfortable and this stent has a more favourable long-term patency rate for 2 years, but more episodes of dacryocystitis and stent migration have been demonstrated. Purpose: Percutaneous RFA of liver tumors has been extensively described and is considered safe and effective. Targeted CO 2 insuffl ation has been described by Raman et al. as a way to manipulate intraabominal organs to gain safe access routes. However, these authors stressed several drawbacks to this technique, including possible increased bleeding, limited role of ultrasound guidance, and inherent risks in CO 2 insuffl ation. We offer a new approach in using a balloon catheter as a diaphragmatic protective device. Methods and Materials: A balloon catheter was placed above the level of the hepatic dome in eight pigs under general anesthesia. Approximately 50-70 ablations were performed with the balloon as a protective device. Fourteen control lesions were performed without the balloon. Thermal injury to the adjacent diaphragm was examined to determine depth of injury.

The balloon catheter provides a protective barrier that is more stable in position than with saline infusion or CO 2 insuffl ation. The risk of bleeding was not increased because the point of probe entry into the liver remained closely apposed to the abdominal wall. Potential acidosis associated with CO 2 insuffl ation was also never a concern. Conclusion: Our model of using a balloon catheter as a protective device has several advantages over the CO 2 insuffl ation model, and provides a safe and effective way of expanding the use of percutaneous radiofrequency ablation of liver tumors that are in the undersurface of the diaphragm. Additionally, this novel method may be used in the protection of other organs adjacent to areas being ablated. 

Results were classifi ed as primary success when complete pain relief was obtained after a single ablation session, secondary success when two or three sessions were performed and failure when persistence of pain required another therapy. Complications were also recorded. Results: Osteoid osteomas located in nearly every part of the skeleton including the spine were managed with this technique. Primary success was obtained in 145 cases (94%), secondary success in 8 cases (5%), and failure in 2 cases (1%). In 2 cases, the procedure was complicated by secondary algodystrophy. Conclusion: Laser ablation is a safe and effective technique which could represent the mainstay therapy for osteoid osteoma.

An investigation of brightness changes in ultrasound images due to variations of temperature in liver tissue during ex vivo and in vivo radiofrequency ablation A. Montaseri, M. Mokhtari Dizaji, S. Akhlaghpour, M. Alinaghizadeh; Tehran/IR (atmostellae@yahoo.com)

Purpose: A minimally invasive method for the treatment of liver malignancies is radiofrequency ablation, after which disease recurrence is probable, partially due to inadequate capability of temperature monitoring of the target tissue. The goal of this work was to study the possibility of real-time temperature monitoring of liver tissue undergoing RFA. For this purpose, variations of brightness in ultrasonic images acquired from ex vivo and in vivo experiments were investigated.

In our ex vivo experiments, pieces of fresh bovine liver underwent RFA using active and passive needle electrodes and a microthermometer, which were inserted into the tissue using ultrasonography guidance. Tissue samples were heated up to 70 °C and corresponding to each centigrade of temperature increase, ultrasonic images were acquired and delivered to a PC. Variations of image brightness were investigated. In our in vivo experiments, the changes of brightness were studied in the ultrasonic images acquired during the RFA of liver malignancies of three patients. Temperature increase was monitored using thermocouples at the tip of the RF electrode prongs.

The ex vivo study showed that during tissue warm-up from 22 °C to 50 °C, brightness in ultrasound images increases linearly. As temperature rises from 50 °C to 70 °C, variation of brightness shows a non-linear behavior due to microbubble formation. The in vivo investigations showed good consistency with ex vivo results in the 40-60 °C interval.

Conclusion: It appears that changes of brightness in ultrasound images can be used for real-time thermal monitoring during RFA.

FDG-microPET and diffusion-weighted MR image evaluation of early therapeutic effects of radiofrequency ablation on implanted VX2 rabbit tumor in the back muscle T. Ohira, T. Matsuoka, T. Okuma, Y. Wada, K. Koyama, K. Nakamura, Y. Watanabe, Y. Inoue; Osaka/JP Purpose: To evaluate the early therapeutic effects of radiofrequency ablation (RFA) on implanted VX2 rabbit tumor in the back muscle using FDG-microPET and MR image.

The bilateral back muscles of 7 rabbits were implanted with VX2. A week after tumor implantation, a LeVeen needle electrode was percutaneously inserted under CT guidance and radiofrequency was applied until maximum impedance. The other side of the VX2 remained as the control tumor. MR imaging was performed with a clinical 1.5 T instrument using a knee coil 2 days after RFA. Spin-echo T1-weighted images (T1WI), fast-spin-echo T2-weighted images (T2WI), Gd-enhanced T1-weighted images (CE-T1WI) and echo-planar-imaging-diffusion-weighted images (DWI) (b=50, 500, 1000 sec/mm 2 ) were obtained. Apparent diffusion coeffi cients (ADC) of ablated lesions and VX2 were measured. FDG-microPET was obtained 3 days after RFA. Emission data were acquired 40-60 min after intravenous 18 F-FDG injection. RFA lesion-to-muscle (RF/M) and tumor-to-muscle (T/M) ratios were calculated. Results: VX2 without RFA showed ring-shaped FDG accumulation and hyperintensity on T1WI, T2WI, CE-T1WI, and DWI, while ablated lesions showed less accumulation and hypointensity on all sequences. ADC values and T/M ratios of VX2 without RFA were 1.69±0.35 × 10 -3 mm 2 /sec and 11.6±3.2, respectively. After RFA, ADC values and RF/M ratios were 1.30±0.27 × 10 -3 mm 2 /sec and 0.5±0.3, respectively. ADC values and RF/M ratios were signifi cantly lower than the VX2 without ablation (P < 0.05). Histology showed coagulative necrosis and no viable on ablated lesions. Conclusion: Both FDG-microPET and MR images may be useful for evaluating early therapeutic effects of RFA.

A new challenge for radiologists: Ultrasound guidance in regional anesthesia L. Learning Objectives: To review the equipment and practical use of ultrasound relevant to the practice of regional anesthesia. To show the sonographic anatomy of the areas most frequently involved in regional anesthesia, and to become familiar with the imaging appearance of nervous structures. To describe and illustrate the sonographic appearance of peripheral nerves. To discuss the advantages of ultrasound-guided plexus and nerve blocks. Background: The ultrasound guidance for nerve block was fi rst reported by La Grange et al in 1978, but the interest has increased in the last 10 years due to the technological advances experienced in ultrasound and regional anesthesia. An optimal distribution of local anesthetic around the nerve structures is the key requirement for successful regional blocks, and ultrasound allows direct visualization in real time. Ultrasound-guided regional blocks improve the quality (faster onset and duration), reduce the performance time and complications, and minimize the amount of local anaesthetic used. Procedure Details: It is essential to know the specifi c anatomy and the sonographic correlation of the areas usually involved in the regional blocks of the upper (interscalene, infraclavicular, axillar, and peripheral blocks) and lower extremities (femoral, sciatic, popliteal blocks). We describe and illustrate the technique used in our hospital by the department of anesthesia in collaboration with the radiology department. Conclusion: Utilization of ultrasound guidance for regional blocks is on the rise and has demonstrated to be an alternative to traditional methods of regional anesthesia. It enables quality nerve blocks, avoiding complications by optimal needle positioning.

Radiological Purpose: To describe the technique and to evaluate the results of a radiologicalendoscopic combined approach in patients with biliary ducts iatrogenic damage.

Eighteen patients with complete biliary ducts transection underwent a radiological-endoscopic rendez-vous. The damage of the biliary ducts was due to trauma in 1 case and to videolaparoscopic colecistectomy in 17 cases. The procedure consists in re-establishing the continuity of the biliary ducts with a combined radiological-endoscopic approach, dilation, and placement of two percutaneous biliary drainages. After 4-6 weeks, the drainages are replaced with 3-6 endoscopic plastic endoprosthesis that are left for 12-14 months.

The rendez-vous technique was performed successfully in all cases with fast resolution of the symptoms. Two patients underwent surgery, while in 16 patients the biliary drainages were substituted with plastic endoprosthesis. After the removal of the endoprosthesis, 9 patients are asymptomatic after 3-18 months. Seven patients are still in treatment with biliary endoprosthesis and are asymptomatic after 3-18 months follow-up.

The radiological-endoscopic combined approach represents the only approach in patients with complete biliary duct transaction to delay or avoid the surgery. Slice concept-the needle must remain in the plane of the ultrasound beam slice; Angle of needle -poor refl ection at steep angles, good refl ection and therefore visualisation at shallow angles. This can be achieved by "heel toeing" the probe and choosing point of entry carefully; Machine settings-Adjusting depth, focus and gain plus using an appropriate frequency probe. Conclusion: For ultrasound guided procedures to be carried out successfully and safely require visualisation of the needle. This diffi cult task can be simplifi ed by considering some applied physics and following some simple tips.

Percutaneous parapedicular access to the thoracic and lumbar vertebral bodies D.P. Beall; Oklahoma City, OK/US (dpb@okss.com)

Learning Objectives: To demonstrate a technique for parapedicular access to the vertebral body. To present the anatomy of the spine as it relates to a safe and reproducible method of percutaneously accessing the vertebral body. Background: The thoracic and lumbar vertebral bodies and pedicles differ in size and shape according to level. The method of accessing the vertebral bodies for percutaneous management of vertebral compression fractures and for biopsy has typically been via the parapedicular approach in the thoracic spine and the transpedicular approach in the lumbar spine. While the transpedicular approach is safe and effective, the ability to redirect the needle is limited, and there is a risk of fracturing the pedicle itself. Procedure Details: The parapedicular approach does not have the risk of pedicular fracture and the needle is more easily redirected with this approach, but the neurovascular structures are important to identify and avoid. The needle is placed in at the pedicle-body junction along the superior half of the pedicle and is directed toward the contralateral inferior vertebral endplate. The medial wall of the pedicle must not be transgressed prior to entering the posterior portion of the vertebral body.

We present a technique for parapedicular access to the vertebral body that will provide a relatively avascular and aneural approach to vertebral body, is reproducible in the thoracic and lumbar spine, and will allow a consistent unilateral approach to the center of the vertebral body.

CT Step-to-step insertion of the needle and application of drugs after suffi cient contrast media application are performed. Conclusion: CT guidance helps in avoiding puncture of vessels by direct visualization, thus enhancing safety. A multidisciplinary patient management improves results concerning pain and quality of life. A "how-to-do approach" will introduce the reader to CT-guided interventional pain management of the cervical spine.

Sedation Learning Objectives: 1. To present an overview of pharmacokinetics and pharmacodynamics of most widely used drugs for sedation. 2. To be acquainted with their principal indications and contraindications. 3. To explain the basic safety regulations to follow during a sedation procedure. Background: Nowadays, there are a high number of diagnostic and therapeutic procedures conducted under sedation, analgesia or immobilisation. Because of this, radiologists often carry out the sedation procedures by themselves. It is the responsibility of the radiology and anaesthesia departments of every hospital to implement a working pattern based on collaboration among their staff, so that every radiologist becomes profi cient enough to guarantee high levels of safety and quality during a sedation procedure. Procedure Details: We present the basic pharmacokinetics and pharmacodynamics of the drugs most widely used (propofol, midazolam, etomidate, ketamine and fentanile), and their adverse reactions and treatment as well as their indications and contraindications. The basic notions necessary to recognise and verify (BIS ® and entropy) the different consciousness levels are exposed. Finally, the main safety rules of the American Society of Anesthesiologists about this issue are detailed.

In order for radiologists to perform sedation procedures, it is of utmost importance for them to be acquainted with the basic pharmacology of the drugs employed, their indications and different options available for each procedure. Similarly, it is necessary to become familiar with the management of the airway, the safety devices and basic and advanced cardiopulmonary resuscitation. 

CT-guided percutaneous radiofrequency ablation of the pulmonary and mediastinal unresectable tumors adjacent to the heart and large vessels C. Pusceddu 1 , G. Podda 1 , C. Urigo 2 , F. Meloni 2 , S. Profi li 3 , G. Meloni 2 ; 1 Cagliari/IT, 2 Sassari/IT, 3 Tempio Pausania/IT (curigo@sirm.org)

Purpose: To verify the feasibility and safety of radiofrequency thermal ablation (RFA) under CT guidance in the treatment of malignant neoplasm adjacent to the heart and large vessels. Methods and Materials: Twelve patients (mean age of 64 years) with unresectable primary and secondary pulmonary and mediastinal tumors (3 NSCLC, 1 invasive thymoma, 1 mesothelial sarcoma and 7 metastases) were treated by CT-guided RFA. The tumors, 3 of the mediastinum and 9 of the lung, were adjacent to the aorta (7 cases), pulmonary artery (4 cases) or heart (3 cases) with potential thermal damage of these structures. All ablations were performed with a multitined expandable electrode under conscious sedation and local anesthesia. Vital signs of the patients 446 B D E F A G were non-invasively monitored continuously. The therapeutic outcomes were evaluated by contrast-enhanced CT after 1 month; the absence of tumor enhancement CT image was considered to indicate complete tumor necrosis. Two patients were re-treated. In a patient, an electrode is penetrated in the pericardium. Results: In all cases, the procedure was technically successful. No intraprocedural arrhythmia occurred. Morbidity existed in 3 cases of pneumothorax and 1 case of asymptomatic thickening of the pericardium. In the control CT after 1 month, there was complete necrosis in 7 cases and partial (from 70 to 90%) in the remaining 5 cases. Conclusion: RFA of mediastinal and lung tumors adjacent to the heart and large vessels is feasible and safe because the blood fl ow causes a "heat-sink" effect adjacent to such structures and prevents undesired thermal damage.

New needle guidance system to reduce ultrasound-guided biopsy operator dependence A. Shaikh, N. Bluvol, A. Kornecki, A. Fenster; London, ON/CA (allisoncanada@hotmail.com) Purpose: The speed of accurate ultrasound (US) guided biopsy is dependent on operator experience. We developed a needle guidance system (NGS) to increase the speed and accuracy of biopsy procedures using US. This system is composed of a passive articulated mechanical arm attached to an US transducer, providing real-time projected needle pathway overlay guidance. This NGS coupled to a CNB needle will result in accurate biopsy with shorter procedure time than those of freehand technique, thus potentially limiting the US biopsy operator dependence. Methods and Materials: Biopsy targets composed of 2.5 mm blue PVAC lesions were implanted within chicken tissue test phantoms. Two radiologists experienced with US-guided biopsy and 3 inexperienced radiology residents performed biopsy of these lesions using both the free-hand technique and NGS (45 lesions per technique per participant). Participants were alternately assigned to start with 1 of the 2 biopsy methods, which were video recorded and analyzed for procedure time. Biopsy samples were examined for the presence of blue color, which was indicative of a successful biopsy. Results: Biopsy procedure time using the NGS was signifi cantly lower than the free-hand technique (p < 0.001). The average procedure time was shorter among experienced participants than among inexperienced participants when using the free-hand technique (p=0.037). Equivalence in procedure time was found when physicians, both experienced and inexperienced with free-hand US biopsy, performed biopsy using the NGS (p=0.734). Conclusion: Our needle guidance system is increasing procedural effi ciency by improving the rates of successful biopsy and reducing the required physician experience to perform biopsy.

Complications of percutaneous RF ablation of primary and secondary liver tumours: Report of a single center study P. The magnet-insertion procedure was performed under endoscopic and fl uoroscopic guidance. Two coated rare-earth-metal (NdFeBr) magnets (Br = 1200 Gauss, d = 10 mm, central hole d = 6 mm) were inserted by guide-wire and duodenal probe into the model. The fi rst magnet was pushed into the fi rst jejunal loop, the second one was placed into the stomach inversely. After reaching the adequate positions, the magnets were pushed down from the guide-wire to let them cohere. Results: The exact positioning was possible; the magnets cohered across the gastric and jejunal walls successfully. Expectedly, the pressure between the magnets leads to ischaemia and necrosis of the cohered gastric and jejunal walls, while reparing the granulation process along the magnets' edges yields adhesion between them, and fi nally an anastomosis will develop. Conclusion: The experiment was executable even with common tools in a short period of time in an exact way. Further developments are necessary regarding size, material and form of the magnets. With some slight technical corrections, the method seems to be suitable for animal experiments.

Percutaneous alcohol ablation and catheter drainage for the treatment of large hydatid cysts in liver S.K. Puri, A. Dev, S. Ghuman, A. Agarwal, A.S. Puri, P.K. Mishra, S.K. Sarin; New Delhi/ IN (skpurigbph@yahoo.co.in) Purpose: To evaluate the safety and effi cacy of percutaneous alcohol ablation using a catheter and subsequent drainage of the cavity in large, > 8 cm hydatid cysts in liver.

Sixteen patients (6 men and 10 women, aged 22 to 52 years) with 18 hydatid cysts were subjected to alcohol ablation and catheter drainage. All cysts were of Gharbi type I and II and the size ranged from 8 to 14 cm. The procedure was performed under US guidance (n=12) or CT guidance (n=4) using light sedation and local anesthesia. Initial needle puncture and aspiration of fl uid were done to examine scoleces and rule out any biliary communication. 

To differentiate angiogenic profi le in tumors using α ν β 3 -specifi c USPIO C. Purpose: Angiogenesis is essential for tumor growth and spread. In this study, α ν β 3specifi c ultrasmall superparamagnetic iron oxide (USPIO) was generated and its potential to distinguish tumors with different angiogenic profi le was investigated. Methods and Materials: APTMS-coated USPIO with diameters of 10±3 nm were conjugated with RGD-peptides. RGD-USPIO or plain particles were injected into nude mice bearing HaCaT-ras-A-5RT3 and A431-tumor xenografts. T 2 -and T 2 *weighted MR imaging and T 2 -relaxometry were performed 6 h after injection. Tumor tissues were immunostained against CD61 and counterstained against CD31. Area fractions of CD31 and α ν β 3 integrin positive vessels were determined. Results: On T 2 *-weighted images, a strong heterogeneous decrease in signal intensity was found in HaCaT-ras-A-5RT3 tumors, while signal changes in A431 tumors were more homogeneous and less pronounced. Both in HaCaT-ras-A-5RT3 and in A431 tumors, T 2 -relaxation times decreased signifi cantly (p < 0.05) more after the injection of RGD-USPIO than after the injection of plain particles. In addition, the decrease in T 2 -relaxation time in HaCaT-ras-A-5RT3 tumors (28 ± 41 ms) was stronger than in A431 tumors (14 ± 8 ms). In line with the MR results, histological evaluation shows in HaCaT-ras-A-5RT3 tumors a heterogeneous vascularization with areas of high vessel density and large mature vessels. Contrarily, in A431 tumors, the vessels were small and homogeneously distributed. Furthermore, in HaCaT-ras-A-5RT3 tumors, signifi cantly (p < 0.01) higher area fractions of CD31 (1.9±1.1%) and α ν β 3 integrin positive vessels (1.0±0.5%) were found than in the A431 tumors (CD31/α ν β 3 integrin area fraction: 0.9±0.4%/0.3±0.1%). Conclusion: Molecular MRI of angiogenesis using α ν β 3 -specifi c USPIO can distinguish tumors with different angiogenic profi les in vivo.

Whole body diffusion weighted magnetic resonance in tumor imaging: Technical improvement and preliminary results S. Li, F. Sun, H.D. Xue, Z.Y. Jin; Beijing/ CN (lishuo_lee@yahoo.com.cn) Purpose: To optimize the free breathing whole body diffusion weighted imaging (WB-DWI) protocol by using short TI inversion recovery diffusion weighted echo planar imaging (STIR-DWEPI) sequence and build in body coil. High resolution three-dimensional (3D) maximum intensity projection (MIP) images were obtained and the feasibility in tumor patient screening was evaluated. Methods and Materials: 1) Prescan procedure of STIR-DWEPI was modifi ed under the data from thirty volunteers scan. During each exam, an optimized center frequency was used to minimize the slice offsets in the consecutive scan station.

Prescan time was also reduced from 50 seconds to 20 seconds with even better station profi le. Total scan time is 30 minutes for 5 stations 1.2m coverage; 2) Thirty patients with histological proven malignant disease were scanned under the fi nal protocol by build in body coil for feasibility evaluation. The image quality and the degree of background body signal suppression were also assessed. Results: Free breathing WB-DWI is 100% successfully performed in this patients' group, without slice misregistration, fat contamination, signifi cant distortion or nonuniformity. The acquired 3D-MIP images were adequate in depicting the malignant lesions on the total 30 patients with high sensitivity and accuracy, compared with PET or SPECT results. Conclusion: High resolution images of WB-DWI can be obtained with these technical improvements. WB-DWI has a great clinical application value in the detection of primary and metastasis lesions of malignancies in the whole body. It has great potential in diagnosis and therapeutic assessment of tumors.

Changes Purpose: To prospectively compare the agreement between low-dose unenhanced PET/CT and full-dose enhanced PET/CT in lesion detection and staging of Hodgkin disease and non-Hodgkin lymphoma. Methods and Materials: Seventy-two biopsy-proved lymphoma patients underwent 18 FDG PET/CT that included a low dose unenhanced CT and a full-dose enhanced CT for initial staging. Every patient had both PET/CT studies, and each one was evaluated by one pair of experienced physicians, a radiologist and a nuclear physician. Both pairs were blinded to the other technique. Lesion detection, number of sites affected in each anatomical region, and disease stage were assessed with both imaging modalities. Agreement among techniques was determined by kappa statistics, and discordances studied by McNemar's test. Clinical, analytical, histopathologic, diagnostic enhanced-CT, PET, and follow-up data constituted the reference standard. Results: For region-based analysis, no signifi cant differences were found between low-dose PET/CT and full-dose PET/CT, although full-dose PET/CT showed fewer indeterminate fi ndings and higher number of extranodal sites affected. Agreement between both modalities of PET/CT was almost perfect for disease stage (k =0.92, p < 0.001).

No statistically signifi cant differences were found between both modalities of PET/CT in the initial staging of patients with lymphoma, although full-dose enhanced PET/CT detected a larger number of anatomic sites affected, especially in extranodal regions, and provided fewer indeterminate fi ndings than low-dose unenhanced PET/CT.

Conjugation of single-chain antibody against human γ-seminoprotein to iron oxide and its in vitro identifi cation Y.D. Han 1 , Y.G. Zhang 1 , Y. Ji 1 , D.X. Cui 2 , J.Q. Xu 1 , Y.L. Liu 1 ; 1 Xi'an/CN, 2 Shanghai/ CN (Hanyuedong@ 126.com) Purpose: To synthesize the conjugate of single-chain Fv (scFv) iron oxide against human γ-seminoprotein, and identify its biological activity in vitro. Methods and Materials: E4B7 scFv gene was amplifi ed by PCR and then expressed by the rapid translation system. The product was studied by immunoprecipitation, western blotting, and immunofl uorescent staining, and subsequently conjugated with magnetic nanoparticles (MNP) 8 nm in diameter, which were further coated with aminosilane and PAMAM dendrimer. The conjugated and the unconjugated MNP were separately incubated with the prostate cancer LNCaP cells and then observed via transmission electrical microscopy (TEM). Results: The E4B7 scFv gene was successfully amplifi ed and expressed. The result of immunoprecipitation and western blotting showed that the expressed peptide was completely absorbed by the soluble cytoplasmic fraction and cell membrane of LNCaP cells, which is highly consistent with the result of immunofl uorescent staining. TEM showed that the conjugate entered into the cytoplasm within 15 min, and the amount increased over time, unlike unconjugated MNP in the control group, in which the amount inside the cells was markedly less than that of the conjugate at the same time point, although they also entered into the cytoplasm.

The scFv peptide against human γ-seminoprotein, and the conjugate of scFv-MNP were successfully fabricated, with the latter being uptaken by LNCaP cells. Our studies indicate that this targeted probe can be developed for further molecular MR imaging. 

(b= 50, 500, 1000 sec/mm 2 ). Results: Tumor size at 1 and 2 weeks after implantation was 1.6±0.2 cm and 1.9±0.2 cm (±SD), respectively. The FDG-microPET image shows ring-shaped accumulation in the tumors. The T/M ratios of the tumor rim at 1 and 2 weeks, and tumor core were 11.6±3.7, 7.6±2.7, 3.3±2.6, and 4.0±2.9, respectively. The T/M ratio of the rim at 1 week was signifi cantly higher than at 2 weeks (P < 0.05). MR imaging shows a slightly hyperintense tumor on T1WI, hyperintense on T2WI and DWI, and ring-like enhancement on Gd-T1WI. The ADC values of the rim at 1 and 2 weeks, and the core were 1.60±0.4x10 -3 , 1.90±0.4x10 -3 , 1.51±0.5x10 -3 and 1.58±0.5x10 -3 (mm 2 /s), respectively. The ADC values of the rim at 1 week were signifi cantly lower than those at 2 weeks (P < 0.05). Conclusion: Our preliminary study suggests that FDG-microPET and MR image can be used to characterize the VX2 tumor.

In Purpose: To develop a method for labelling human cytotoxic T-lymphocytes with superparamagnetic iron oxide particles (SPIOs) for subsequent depiction with a conventional 1.5 T MR scanner.

A CMV-specifi c CD8 + cytotoxic T-lymphocyte (CTL) clone was expanded in the presence of feeder cells, Interleukin (IL)-2 and IL-15 and stimulated unspecifi cally with anti-CD3. After three days, CTLs were labelled either by incubation with Resovist or with Resovist and Lipofectin (20µg/ml) at 100 or 200µg Fe/ml with an incubation time of 4 hours. Cells (2x10 6 ) were imaged at 1.5 T (Philips Intera) 0, 2, 7 and 14 days after labelling using a fast multi-echo readout sequence to determine T2 * -relaxivity. Resovist-uptake was confi rmed by immunofl uorescence using an antibody specifi c for the dextran-coating of Resovist. Specifi ty of CTLs was determined by staining with a CD8-antibody and CMV-multimers. Specifi c cytotoxicity was quantifi ed by a 51 Cr-release-assay. Iron uptake was measured by atomic emission spectrometry (AES).

Results: Resovist-labelling of CTLs was most effi cient using Resovist (100µg Fe/ml) and Lipofectin. On days 0 and 2 after labelling, pronounced shortening of T2-and T2 * -relaxation times was observed which diminished substantially after 7 and 14 days. The mean iron concentration per cell was 0.9 and 0.8pg at 0 and 2 days after incubation and 0.1pg at 7 days. Specifi ty and specifi c cytotoxicity of the cells was not altered by the labelling procedure. Conclusion: Labelling of human CTLs can be achieved by incubation with Resovist and Lipofectin. A possible future application could be the monitoring of CTLs after an adoptive cell transfer.

Molecular imaging of axillary lymph node by equivalent cross relaxation rate S. Matsushima 1 , H. Nishiofuku 2 , F. Sasaki 2 , S. Era 1 , Y. Kinosada 1 ; 1 Gifu/JP, 2 Nagoya/JP (smts@cc.gifu-u.ac.jp) Purpose: Equivalent cross-relaxation rate (ECR) imaging (ECRI) is a measurement method that can be used to quantitatively evaluate a change in the structural organization of lymph nodes by MRI. The aim of this study was to evaluate the utility of ECRI as molecular imaging. Methods and Material: Fifteen patients with histologically confi rmed invasive ductal carcinomas of the breast were studied. We adopted the off-resonance technique for preferential saturation of the immobile protons to evaluate the ECR values. The single saturation transfer pulse frequency was employed at the frequency 5 ppm downfi eld from the water resonance. The ECR value was defi ned as the percentage of signal loss between the unsaturated and saturated images. The ECRI was constructed on the basis of the percentage of ECR. The 50 ROIs had a rectangle-sampling area of 0.3 mm 2 . The Winroof software was used to analyze the number of cells.

The normal organization showed that there were many cells and a higher ECR value. The lymph nodes with metastases showed that there were few cells and a lower ECR value. In the adipose tissue there were very few cells and the lowest ECR value. A statistically signifi cant difference was obtained in the ECR values of each tissue (p < 0.001). Both numerical values are present on the fi rst correlation line (correlation coeffi cient = 0.92).

In the axillary lymph node, ECR value related to the number of cells. Therefore, ECRI is a potentially useful method for molecular imaging in the lymph node.

Pathological animal models in the experimental evaluation of tumor microvasculature with magnetic resonance N. Faccioli, P. Marzola, F. Boschi, M. D'Onofrio, R. Pozzi Mucelli; Verona/IT (nfaccioli@sirm.org)

Purpose: To evaluate the applications of Magnetic Resonance and in particular of Dynamic Contrast Enhancement Magnetic Resonance Imaging (DCE MRI) in the study of tumoral microcirculation by means of animal tumoral models, evaluated before and after antiangiogenic treatment. Methods and Materials: Forty-two MR exams were executed with intravascular contrast media in 21 rats: in 7 rats, tumors were induced by the subcutaneous injection of colon carcinoma cells, and in 14 rats by mammary adenocarcinoma cells. Perfusional and permeability parameters of the implanted tumors were evaluated with two contrast media (B22956/1 and Gd-DTPA37-albumin) to depict better the tumoral response after administration of two different antiangiogenic drugs (Tamoxifen and SU6668). By means of these parameters and histological examination, it was possible to obtain a map of the microcirculation. Results: In all the examined animal models, the DCE-MRI shows that the enhancement is greater in the peripheral area than in the central area. After the antiangiogenic drug administration, the mean values of permeability and perfusion were decreased to 51% and 59%, respectively. The response to the treatment is different for each antiangiogenic drug. Different contrast media allow a different capability to visualize the microcircle. Conclusion: DCE-MRI permits the non-invasive evaluation of tumoral microcirculation, and in particular, of its size, dynamic characteristics and vascular grade before and after antiangiogenic treatment.

Eosinophilic granuloma B. Graca, J. Brito, A. Canelas, P. Belo-Oliveira, C. Marques, F. Caseiro-Alves; Coimbra/ PT (pombas@gmail.com) Learning Objectives: To provide an educational and pictorial review of the radiological imaging features (plain radiography/ bone scintigraphy/CT/MRI) and distribution of eosinophilic granuloma (EG). To illustrate the clinical features and peculiar radiological appearances of eosinophilic granuloma. To discuss differential diagnoses, in particular in differentiating eosinophilic granuloma from other primary bone tumours, metastases or osteomyelitis. Background: Langerhans cell histiocytosis is a pathological entity characterized predominantly by proliferation of a specifi c histiocyte (Langerhans cells). The etiology and pathogenesis is still unknown. Eosinophilic granuloma is the unifocal unisystem form of Langerhans cell histiocytosis, typically characterized by bone involvement, usually in a monostotic pattern. Nonetheless, it is important to be able to recognize this lesion and exclude diffuse involvement, particulary of the bone marrow, lungs, heart, liver, kidney and gastrointestinal tract, conferring an adverse prognosis. EG must be differentiated from neoplastic, infl ammatory and metabolic lesions, which have variable approaches in terms of prognosis and treatment. Eosinophilic granuloma may resolve spontaneously. There are good results with intralesional injection of methylprednisolone. Surgery, chemotherapy and radiotherapy are reserved for disseminated or complicated cases, which is rarely the case of EG. Imaging Findings: We divide our presentation by anatomical location, showing lesions of the calvarium, mandible, ribs, vertebra, and long bones, emphasizing the most important aspects in differential diagnosis, in different imaging modalities. Conclusion: Awareness and early identifi cation of eosinophilic granuloma allow appropriate management. We provide a review of the background, clinical presentation and radiological feature of eosinophilic granuloma. Purpose: MRI, radionuclide imaging and bone densitometry have been used for quantifying skeletal involvement in patients with Gaucher disease (GD). In this study, we compared different quantitative/semiquantitative methods for assessing skeletal involvement in patients with GD based on MRI, scintigraphy or dual-energy X-ray adsorptiometry (DEXA).

Thirty-one patients with type-1 GD underwent MRI, 99mTc-sestamibi scintigraphy and DEXA. MRI was performed with 1.5 T scanner; protocol included T1 and T2w TSE sequences of lumbar spine and femora. All images were analysed by 2 radiologists and bone marrow changes were classifi ed on a 16-point semi-quantitative scoring system. 99mTc-sestamibi scintigraphy was semiquantitatively scored; DEXA of the lumbar spine and femoral neck yielded the Z-and T-scores. The relationship between MRI, scintigraphic and DEXA scores and different disease parameters (bone pain, skeletal complications, hepatomegaly, splenomegaly, platelet count, haemoglobin level, and plasma chitrotriosidase) was evaluated by the Spearman's rank correlation test. Results: A statistically signifi cant correlation was found between MRI and scintigraphic scores (r = 0.694; P = 0.0001). Moreover, both imaging scores were statistically signifi cantly correlated with several clinical parameters including platelet count, hepatomegaly, splenomegaly, haemoglobin level and presence of skeletal complications. On the contrary, the DEXA-derived parameters were not correlated with any clinical and/or imaging scores. Conclusion: Our preliminary data indicate that both MRI and 99mTc-sestamibi scintigraphy are reliable tools for assessing the severity of bone marrow involvement in patients with GD. Learning Objectives: To describe the clinical, pathological and radiological features of osseus tumours that contain osteoclast-like giant cells. To understand the pathologic basis of the radiologic features of these lesions. To realize the problems and pitfalls in the pathology assessment and discuss the clinical and radiological features that may allow differential diagnosis. Background: Differential diagnosis of bone lesions that contain giant cells requires the pathologist to consider an important number of possibilities. Each lesion should be analyzed as a clinicopathologic entity and, therefore, the pathologist should be aware of the relevant clinical information and the radiologic evaluation of the lesions. Procedure Details: We have divided these lesions into two groups. The fi rst one includes lesions that can be mistaken for a benign giant cell tumor (BGCT) because of its histologic similarity or its location in long bones extremities (chondroblastoma, giant cell reparative granuloma, cherubism, brown tumor of hyperparathyroidism and intraosseus nodular synovitis). The other group consists of lesions that also contain giant multinucleated cells but are histopathologically very different from BGCT (osteosarcoma, osteoblastoma, osteoid osteoma, fi brous dysplasia, condromixoid fi broma, cemento-ossifying fi broma, aneurysmal bone cyst, fi brous histiocytoma, eosinophilic granuloma and Paget disease) Conclusion: The radiologist's role is essential to diagnose and treat osseus tumours that contain osteoclast-like giant cells, because it allows differentiation between them and informs about its biologic potential. Periostic reaction, borders, soft tissue mass and calcifi ed matrix are the best radiological features that are helpful in differential diagnosis. Location and patient age are the best clinical clues.

Interobserver reliability of a CT classifi cation system in the calcaneus fracture P. Jiménez Villares 1 , F. Ruiz Santiago 2 , A. Peralta Silva 1 ; 1 Cádiz/ES, 2

Purpose: This study was designed to determine the interobserver reliability of a calcaneus fracture classifi cation scheme. For a fracture classifi cation to be useful, it must provide prognostic signifi cance and intraobserver reproducibility. Most studies have found reliability and reproducibility to be poor for fracture classifi cation schemes. Methods and Materials: Eighty-nine cases were selected that had an appropriate study of CT image from a trauma hospital center. Two radiologists from the musculoeskeletar department reviewed all these studies. On each viewing, observers were asked to classify the fractures according to both the Sanders and Crosby-Fitzgibbons and Zwipp systems. Interobserver reliability and reproducibility were assessed with computer-generated kappa statistics. Results: Sander classifi cation: The mean kappa value for interobserver reliability for fracture types I-IV was 0.852. Crosby classifi cation: The mean kappa value for interobserver reliability for fracture types was 0.903. Zwipp classifi cation: The mean kappa value for interobserver reliability for fracture types I-VI was 0.833. Duparc

classifi cation: The mean kappa value for interobserver reliability for fracture types I-V was 0.63. Conclusion: Although intraobserver kappa values reached substantial levels and the Crosby-Fitzgibbons system generally showed greater agreement, we were unable to demonstrate excellent interobserver reliability with either classifi cation scheme. The results indicate that in a carefully controlled paradigm, the interobserver reliability with a classifi cation system based on interpretation of a single carefully defi ned CT image was good in all the systems and better in the Crosby classifi cation.

Spinal 

We studied 90 healthy adults with d-MRI of the lumbar spine. ROIs were placed on each lumbar vertebral body, and mean signal intensity to time (SIT) curves were generated for upper (L 1 -L 2 ), lower (L 3 -L 5 ) and all fi ve (L 1 -L 5 ) vertebrae and wash-in and wash-out rates, time to maximum slope and time to peak values were obtained. Patient population was stratifi ed into men and women younger or older than 50 years, and SIT curves were compared among these subgroups. Multiple regression analysis of data was performed to investigate the effect of age and sex. Results: Perfusion of the upper lumbar spine was signifi cantly higher compared to the lower level (p < 0.05). Individuals younger than 50 years showed signifi cantly higher perfusion compared to older ones for both spinal levels. Women demonstrated signifi cantly increased perfusion compared to men of the same age in the upper lumbar spine only. All parameters except time to peak showed a moderate linear correlation with age (0.22<r< 0.32, p < 0.05). Multiple regression analysis revealed age as the most signifi cant factor (p < 0.05) as compared with sex. To understand the pathologic basis of the radiologic features of these lesions. To highlight that anatomopathological fi ndings and radiological features are essential to reach a correct diagnosis. Background: Some vascular lesions of bone are relatively commonly encountered by radiologists, but are uncommonly seen by pathologists. Patients can present with different symptoms and signs and while some tumours manifest as clearly benign, others have non-specifi c imaging features that may simulate malign neoplasms. In addition, sometimes pathology cannot easily differentiate between benign and malign lesions. Imaging Findings: Among a wide sample of vascular bone tumours from our pathologic and radiologic database, the most representative examples have been selected to illustrate their main radiological and pathological characteristics. Each tumour has been described and assigned to one of the two groups: benign or malignant. The most illustrative diagnostic images have been chosen from various imaging techniques (in particular, X-ray, CT and MR) and their subsequent anatomopathological images. The benign tumours that have been reviewed are: hemangioma, cystic angiomatosis, glomus tumor and Gorham's disease. The malignant tumours that have been analyzed are: hemangioendotelioma, ephitheloid hemangioendothelioma and angiosarcoma. Conclusion: After interacting with this exhibit, the radiologist will have an enhanced understanding of vascular bone tumors, including the histopathologic and radiologic features. Both diagnostic tools are crucial to distinguish these lesions and to allow their proper management. 

Osteoid osteoma: Typical imaging patterns in various skeletal parts T. Moser, X. Buy, A. Gangi; Strasbourg/FR (gangi@rad6.u-strasbg.fr)

Purpose: To analyze imaging features of osteoid osteoma in a large series of cases involving the whole skeleton and to defi ne typical patterns for each location.

A search in our database was performed to identify all cases of osteoid osteomas. Diagnosis of osteoid osteoma was based on typical clinical and imaging fi ndings. Additionally most cases underwent image guided ablation in our department and therefore biopsy results and long term follow-up were also accessible. Cases were included in our analysis when at least CT scan images were available for review. For each case, we precised the exact distribution within the skeleton, and within the bone both longitudinally (e.g. epiphyseal, metaphyseal, diaphyseal) and transversally (e.g. cortical, cancellous, subperiosteal). A typical imaging pattern was defi ned for each location. Results: A total of 158 osteoid osteomas were included in our analysis. Distribution in the skeleton was as follows: upper limb (21 cases), spine (21 cases), femur (63 cases), tibia (28 cases), and remaining of the lower limb (25 cases). We were able to defi ne at least one typical imaging pattern in all major bones. Conclusion: Recognition of typical imaging patterns in most bones allows a more confi dent diagnosis of osteoid osteoma with CT scan. Conclusion: WBLD-MDCT represents a reliable diagnostic tool for the assessment of multiple myeloma, allowing not only the detection of typical lytic bone lesions, but also of both medullary and extra-medullary myeloma involvement. Medullary involvement was encountered in all stages of the disease, including patients without osteolysis, and was associated with signifi cantly elevated levels of ß2-microglobulin, a prospective prognostic marker. Therefore, we suggest the inclusion of WBMD-CT into the diagnostic workup of MM patients.

Whole Conclusion: Evaluation of the course of medullary lesions at follow-up was essential, proving to be even more accurate than a combined evaluation of laboratory parameters and osteolytic lesions.

Bone 

Fifty-four patients with clinically suspected bone marrow pathology underwent both conventional and DW MR imaging of the spine with ADC maps generation and quantitative ADC analysis. Of these, 15 suffered from multiple myeloma, 14 had a known primary tumor, 2 suffered from lymphoma and 23 presented with acute back pain without medical history. Results: In patients with multiple myeloma, quantitative analysis was able to differentiate between active disease (mean ADC 0.62) and response to therapy (1.25). In 4 patients without medical history, the evaluation of the ADC maps led to an investigation for a primary tumor. In 10 patients with a known primary tumor, the ADC fi ndings were attributed to metastases (mean ADC 0.61), while in 4 of them an osteoporotic fracture was found (1.65). In 10 patients out of 54, quantitative analysis added critical information that changed the therapeutic strategy. ADC values were not signifi cantly lower in tumor infi ltration (0.62±0.21) than in normal bone marrow (0.77±0.35). Conclusion: DWI with ADC calculation, a method that studies bone marrow pathology on the basis of altered water-proton mobility, has been proved to be a useful tool (in adjunction to the other available conventional sequences) for differentiating between benign and malignant processes of the spine, and may increase the diagnostic potential of MR imaging in the assessment of spinal lesions.

The skeletal manifestations of sickle cell anaemia U. Shaikh, R. Yaddavali, S. Kumar, H. Aniq; Liverpool/UK (usmansh8kh@googlemail.com)

Learning Objectives: To describe the various skeletal presentations of sickle cell anaemia, highlighting imaging fi ndings on conventional radiography and on MRI. Background: Sickle cell anaemia (SCA) is the most common inherited haemoglobinopathy. This haemolytic anaemia is characterized by abnormally shaped red blood cells (RBCs), which are removed from the circulation and destroyed by the reticuloendothelial system, leading to anaemia. However, more signifi cantly, the sickled RBCs cause vascular occlusion, leading to tissue ischaemia and infarction. Patients with SCA are at an increased risk of infection due to abnormalities in host defences and functional asplenia. SCA affects multiple organs, with the clinical manifestations of SCA being predominantly due to anaemia, vaso-occlusion and infection. Imaging Findings: The fundamental skeletal abnormalities consist of marrow hyperplasia, which leads to osteopaenia with a coarse trabecular pattern. In severe cases, medullary cavities are obliterated giving the appearance of generalized increased bone density. Bone infarction secondary to vaso-occlusion is the hallmark of SCA. In adults, it affects the ends of long bones, the central portions of vertebral bodies with typical 'H' shaped vertebrae and the femoral and humeral heads, resulting in avascular necrosis. In older children, the diaphyses of long bones are the site of predilection. Areas of bone necrosis are susceptible to superadded infection, especially from salmonella.

Radiologists play a pivotal role in the clinical management of these patients and they should familiarize themselves with the various skeletal manifestations and complications of sickle cell anaemia, which we present in this pictorial review. Purpose: To verify the bone mineral density in children and adolescents having fractures of the forearm and hand compared to children and adolescents without a fracture after similar adequate traumatic injuries. Methods and Materials: 100 X-ray examinations of the hand or forearm proving a fracture of children and adolescents after adequate trauma underwent a BMD calculation using digital radiogrammetry. All children and adolescents had to fi ll in a questionnaire regarding potential infl uencing factors of bone mineral density (drug intake, diseases, sportive activity, nutrition). BMD-Z-score calculation used regional normative data of children and adolescents, which were obtained from images performed to exclude a fracture after adequate trauma. Results: 80/100 images could be analyzed by DXR technology. 34/80 patients with fractures had a Z-score of -1 (20/34 with a Z-score of less than -2SD). Mean BMD was -0.7 for both males and females. Analysis was possible starting with 6 years of age. Similar results were obtained for MCI values. Main reasons of BMD loss according to the questionnaire were defi cit of sportive activity and false nutritional intake (fast food). Diseases and drug intake were without relevance

Conclusion: Bone mineralization in childhood and adolescence is disturbed in a signifi cant number of children due to wrong nutritional intake and lack of sportive activity. This causes a higher fracture rate, even during growth. Effects on peak bone mass are not yet verifi ed, but can be expected from the defi cit of BMD during growth.

Cartilaginous tumors in the hand: Plain radiographic and MR imaging fi ndings Y. An, J. Kim; Suwon/ KR (jeeykim@catholic.ac.kr) Learning Objectives: To review the radiographic appearances in various cartilaginous tumors occurring in the hand. Background: Cartilaginous tumor is the most common bone tumor in the hand. However, occasionally unusual imaging fi ndings or unusual location of tumors make it diffi cult to diagnose these cartilaginous tumors. Procedure Details: The cases presented include enchondroma, enchondroma protuberans, intracortical chondroma, Ollier's disease, extraskeletal chondroma, osteochondroma with chondrosarcoma, and synovial chondrosarcoma. Conclusion: Examples of each entity as seen as plain fi lms and MR imaging will be presented. Differential diagnosis in patients with chondroid tumors will be discussed. 

Techniques 

Sagittal proton-density-weighted and coronal T2*-weighted MR images with 1024×1024 matrix, 3 mm section-thickness, and 150 mm fi eldof-view were obtained by using a dedicated 8-channel knee coil on a 1.5 T scanner. For comparison, 512-matrix images were also obtained with identical sequences. Focusing on the above-mentioned structures, paired images with 1024-and 512matrix were magnifi ed in a same scale on viewers. Qualitative image analysis was performed using a four- 

Analysis of errors in the MR imaging evaluation of menisci of the knee P. Van Dyck; Antwerp/BE (pieter.van.dyck@uza.be)

Purpose: To determine MR accuracy for diagnosing meniscal tears and to discuss various causes of discrepancy between MR and arthroscopy. Methods and Materials: Medical records of 100 consecutive patients who underwent MR and arthroscopy of the knee at our institution were retrospectively reviewed. Twelve patients underwent prior meniscal surgery. Twenty-three patients had 27 discrepancies between MR and surgical fi ndings. These were independently reviewed by two additional musculoskeletal radiologists in a double blinded fashion.

Original incorrect diagnoses were categorized as either unavoidable, interpretation error or equivocal for meniscal tear. Results: MR accuracy was 88% for the medial and 85% for the lateral meniscus. Of 27 incorrect MR diagnoses, 12 (44%) were unavoidable, 10 (37%) were equivocal B D E F A G and 5 (19%) were interpretation errors. Of the 67 medial meniscal tears, 12 (18%) were missed. Eight (67%) of these 12 were categorized as equivocal, including 3 postoperative menisci. Of the 30 lateral tears, 12 (40%) were missed, 7 (58%) of which were categorized as unavoidable. Of these 12, 11 (92%) showed fraying of the inner edge, which led to minimal resection (n=7) or had minimal tear treated conservatively (n=4). There were 3 false-positive diagnoses, all occuring in the lateral meniscus, 2 of which were unavoidable and 1was an interpretation error. Conclusion: Of all missed lateral meniscal tears, most are unavoidable and related to confusion between what represents fraying and what represents a tear. Unavoidable false-positive diagnoses are infrequent and may be related to incomplete arthroscopic evaluation. Subtle equivocal fi ndings still make MR diagnosis diffi cult, even for experienced radiologists. Learning Objectives: Evaluate the imaging contribution in total hip replacement (THR) management. Background: Digital or plain fi lm imaging permits the diagnosis of a majority of THR complications. CT scan and MRI, usually less useful, are becoming better adapted due to the performance of the latest machines and specialized software. Imaging Findings: Main local complications are acute, consisting of implant fractures, joint dislocation and neighbouring bone fatigue fracture. Chronic complications include soft tissue new bone formation, periarticular tendonitis, bursitis, recurent dislocation and, above all, device loosening without infection due to granulomatous reaction or with intercurrent infection. In case of recurrent dislocation, X-ray or CT scan can be used to evaluate the actual position of the devices and the possible wear. Conclusion: Hip replacement surgery has been one of the most common elective and semi-elective orthopedic operations for the past 25 years. Radiography remains the mainstay of imaging evaluation of hip replacements. The various types of hip replacements can be recognized on radiographs, and many complications have specifi c appearances that the radiologist should be familiar with.

Pitfalls in post-surgical shoulder MRI evaluations P. Pastore, D. Volpe, N. Volpe, F. Murgante, A. Stecco, A. Carriero; Novara/IT (dvolpe@sirm.org)

Learning Objectives: To describe and recognize magnetic resonance imaging (MRI) fi ndings that can be confused with pathological abnormalities in post-operative shoulder; to maximize the accuracy of MRI imaging by providing the most appropriate pulse sequences. Background: Imaging post-operative shoulders has always been a matter of debate, the main controversy being whether MRI or MR arthrography is the best means of answering diagnostic questions. Published data and clinical experience show that conventional MRI is effective in assessing full-thickness lesions, but less capable of differentiating partial lesions and normal fi ndings after surgery. Procedure Details: A number of factors may decrease the accuracy of MRI in evaluating post-operative shoulders, including iatrogenic artefacts, surgical distortions of native anatomy, changes in the signal intensity of tissues, and image degradation caused by metallic artefacts. We show the key points for optimizing post-operative shoulder MRI protocols and try to identify the best technical parameter among the most widely used pulse sequences. Conclusion: When interpreting post-operative shoulder MR images, radiologists must be familiar with all possible pitfalls in order to avoid diagnostic errors.

Dynamic gadolinium-enhanced MR imaging in characterization of growth cartilage perfusion with epiphyseal vascular occlusion X. Li, L. Xia, H. Zheng; Wuhan/ CN (lilyboston2002@163.com) Purpose: To determine the contribution of metaphyseal vascularity to epiphyseal and physeal perfusion with epiphyseal vascular occlusion by using dynamic Gdenhanced MR imaging.

Twelve 2-week-old piglets were randomly assigned into either control or abduction group (12 proximal femurs in each group of 6 piglets). Proximal femoral epiphyseal vascular occlusion was induced by maximal bilateral hip abduction for 2 hours. Dynamic Gd-enhanced MR imaging was performed in normal and abduction hips. For dynamic Gd-enhanced imaging, spoiled gradientrecalled echo images with a temporal resolution of 3.0s were performed, and a total of 96 images were obtained. The enhancement ratios (ER) in various regions of femoral heads were evaluated and correlated with histological fi ndings. Results: In normal hips, we found no signifi cant differences in the ER and the timing of enhancement between physeal cartilage and metaphyseal spongiosa (P> 0.1). However, in abduction hips, the ER of physeal cartilage was lower than that of metaphyseal spongiosa and enhanced more slowly than metaphyseal spongiosa (P < 0.05). Meanwhile, the ER of epiphyseal cartilage remained lower and enhanced more slowly than physeal cartilage (P < 0.001). The ER of physeal and epiphyseal cartilage in abduction was lower and enhanced more slowly than those in the normal (P < 0.001). More transphyseal vessels in abduction were found histologically than those in the normal (P < 0.005). Conclusion: With epiphyseal vascular occlusion, enhancement seems to advance from the metaphysis into the physis and epiphysis, the metaphyseal vascularity might contribute to epiphyseal and physeal perfusion. This research is supported by NSFC (30370430).

Imaging the complications of total hip replacement J.M. Moriarty, J. Kerr, C. Shortt, J. O'Byrne, S. Eustace; Dublin/IE Learning Objectives: The objectives of this exhibit are to describe the anatomic basis behind the complications of total hip replacement, the radiologic features that describe these complications and the new innovations in diagnostic imaging of these features. Background: Of the 600,000 total hip replacements performed worldwide each year, it is estimated that 5% fail at some stage. The type of surgical approach used, prosthesis inserted and method of fi xation employed all have a role in the prevalence and form of complication that can ensue. The role of radiography, arthrography, CT, and MRI in the diagnosis of these complications is rapidly evolving, particularly the use of metal artefact reduction techniques in MRI. Imaging Findings: This exhibit presents a pictorial review of components, methods of fi xation and complications of total hip replacement. The exhibit reviews the role of radiography, scintigraphy, computed tomography, ultrasound, arthrography and MRI in the assessment of common complications including loosening, infection, heterotrophic bone formation, muscular avulsions, and prosthesis impingement. Furthermore, a detailed review of the use of MRI with artefact reduction techniques in the evaluation of deep seated infection, iliopsoas bursitis and abductor avulsion will be presented.

The diverse imaging modalities that may be employed in the evaluation of the myriad complications of total hip replacement is being constantly updated, re-evaluated and added to. In particular, the increasing sensitivity of certain MRI sequences in the setting of metallic prostheses has led to the routine use of MRI as a problem solving tool. To analyze the discordant fi ndings of anterior cruciate ligament (ACL) on sagittal and oblique coronal MR images of the knee, and correlate with arthroscopic fi ndings as the standard. Methods and Materials: One hundred thirty-eight MR images of the knee in patients with suspected internal derangement who subsequently underwent arthroscopic surgery were included. Two radiologists, unaware of clinical details, jointly evaluated ACL on sagittal T2, proton density-weighted images initially and then on oblique coronal images. Reviewers determined the status of ACL as intact (I), partial (P), or complete tear (C) respectively. When interpretation of ACL status was different between both imaging planes, cases were categorized as discordant and correlated with arthroscopic results. Results: A discordant MR fi nding of ACL was seen in 9 of 138 knees (6.5%). Correlation of ACL status on sagittal, oblique coronal images with arthroscopic fi nding was the following: C-P-P in 3, P-I-I in 2, C-I-I in one, C-P-C in 2, and I-P-C in one case. At arthroscopy, total rupture of ant-med bundle with partly intact post-lat bundle was observed in 3 C-P-P; displaced ACL by fat tissue in intercondylar notch and torn meniscal fragment, deformed course by ligamentum mucosum adhesion in 2 P-I-I and one C-I-I; fi brous scar in 2 C-P-C and one I-P-C.

A discordant fi nding of ACL on sagittal and oblique coronal MR images was not frequent, and attributed to remained post-lat bundle, displaced course, and presence of scar. Interpertation of ACL on oblique coronal image seems more accurate than on sagittal images.

Osseous criteria for ankle instability O. Magerkurth, A. Frigg, B. Hintermann, H. Ledermann; Basle/CH Purpose: Some patients suffer from recurrent ankle sprains even after operative ligament reconstruction. One reason could be a disadvantageous joint confi guration. The purpose was to evaluate those parameters of the osseous confi guration of the ankle joint that could determine stability. 

A larger radius of the talus and a smaller tibio-talar sector contribute to osseous instability. These fi ndings are of importance, showing that ankle instability may depend not only on competence of collateral ligaments but also on osseous joint confi guration.

Magnetic resonance imaging evaluation of articular cartilage after autologous osteochondral grafting I. Herrera, S. Fernández-Zapardiel, Y. Herrero, M. Céspedes, P. Calvo, E. Fandiño; Toledo/ES (babel10100@hotmail.com)

Learning Objectives: To illustrate the appearance and outcome of the articular cartilage after treatment of osteochondral patology with multiple autologous osteochondral plugs (mosaicplasty) using magnetic resonance imaging (MRI). Background: Articular cartilage damage is extremely common in today's society. Osteochondral autotransplantation is a surgical technique that is being used increasingly in the treatment of symptomatic focal chondral or osteochondral defect. With more new surgical procedures being used to repair chondral defects, such mosaicplasty, there is an increasing demand for radiologists to evaluate these procedures. Procedure Details: There were 22 patients with focal chondral lesion (19 of the knee and 3 of the ankle) treated with mosaicplasty. Clinical examination, X-ray and MRI were performed on each patient before surgery. The mosaicplasties were normally done with arthoscopic and transferred autologous bone from the donor site to the recipient site into the cartilage defect. After the surgery, for the assessment of a cartilage repair procedure, we used MRI General Electric Signa Horizon LX 1.5 T with axial, coronal and sagittal planes with cartilage-sensitive sequences, such as fat-suppressed T2-weighted fast spin-echo/proton densityweighted or 3D gradient echo sequences. We evaluated the number of plugs, the graft integration to the adjacent hyaline cartilage and bone, congruence of the articular surface, the adjacent bone marrow, the status of the graft donor site as well as associated complications. Conclusion: With its direct multiplanar imaging capabilities, excellent soft tissue contrast and spatial resolution, MRI could be the method of choice for non-invasive follow-up of patients after mosaicplasty.

Shoulder virtual arthroscopy in glenohumeral instability: Image gallery correlation with arthroscopy D. Volpe, N. Volpe, N. Masiello, P. Fornara, A. Stecco, A. Carriero; Novara/IT (dvolpe@sirm.org)

Learning Objectives: Our intent is to correlate virtual arthroscopy images with arthroscopic fi ndings, and to show an image gallery by means of virtual arthroscopic images of main shoulder pathologies. Background: Shoulder MR arthrography (MRA) is now a well-assessed technique based on the injection of contrast medium solution, which fi lls the articular space and fi nds its way between the rotator cuff (RC) and the gleno-humeral ligaments. In case of gleno-labral pathology or partial RC tears, we use an additional sequence that allows obtaining virtual arthroscopy post-processed views to complete the MR evaluation of shoulder pathology. Procedure Details: MR arthrographic sequences (SE T1w and GRE T1 FAT SAT) are provided with a GE 0.5 T Signa and the supplemental sequence is a 3D Spoiled GE T1w positioned in coronal plane. Virtual arthroscopy is performed by means of a dedicated software loaded on a work-station. Conclusion: Shoulder virtual arthroscopy may be useful in diagnostic accuracy, both as an adjunct to clinical and surgical planning, as well as an interactive tool for learning arthroscopic anatomy and pathology. Purpose: To assess the value of virtual arthroscopy of the shoulder. Methods and Materials: Forty patients with shoulder dislocation-translation and/or clinical signs of instability underwent 64 slices MDCT arthrography and virtual arthroscopic reconstruction. All scans were performed using 64-detector row helical CT scanners with following parameters: 200 Kv; 40 mA; thickness 0.6 mm; collimation 0.6; reconstruction increment 0.6 mm; matrix 512 x 512; preparation and acquisition time 10 min. The patients were examined in supine positions with the shoulder in neutral position; intra-articular injection was performed posteriorly, without fl uoroscopic control, administering 20 cc of room air. The data were downloaded to a workstation and virtual arthroscopy performed using a PC-based 3D reconstruction program. A surface rendering algorithm was employed for producing virtual arthroscopic images. Prior to applying the surface rendering algorithm, a threshold value was specifi ed, corresponding to the center of the different density between bony tissue (the brightest pixel) and soft tissue. Surface models then were calculated and displayed employing an imaginary light source Results: MDCT arthrography diagnosed 20 Bankart lesions, 5 Bankart osseous lesions, 5 cuff-rotator tears, 15 Hill-Sachs lesions and 2 SLAP lesions. Virtual arthroscopy detected and visualized all lesions above-mentioned; it provides a further point of view of shoulder joint which is useful for orthopaedic surgeons planning arthroscopy or arthrotomy; it may also serve as a simulation in the teaching of orthopaedic trainees. Conclusion: Virtual arthroscopy is a new technique that has the potential to enhance the diagnostic performance of CT arthrography.

The scapho-lunate joint and the scapho-lunate ligament: Study by ultrasonography A.R. Michaelides, A. Foteinos, G. Setakis, M. Kastania, T. Giannopoulos, S. Chalkias; Chios/GR Purpose: The ultrasound (US) study of scapho-lunate ligament and scapholunate distance.

We studied using US 100 wrist joints (50 healthy persons), with a superfi cial linear US transducer of high resolution (10 MHz). We measured 456 B D E F A G the distance between the scaphoid and lunate bones in (a) neutral position, (b) radial deviation, (c) ulnar deviation; and characterized the visualization of the scapho-lunate ligament in the palmar and dorsal surfaces. The visualization of the scapho-lunate ligament was characterized as completely visualized, partially visualized and non-visualized. Results: The scapho-lunate distance was measured between 2.0 mm and 6.6 mm, with a mean diameter of 4.5 mm. The difference in this distance between left and right arm did not exceed 2.4 mm. There was no signifi cant change in the scapholunate distance during ulnar and radial deviation. The scapho-lunate ligament was completely visualized in 52/100 cases, and partially visualized in 23/100 cases, all being studied dorsally. The scapho-lunate ligament was better visualized by ultrasound in the dorsal surface compared to the palmar one.

The scapho-lunate ligament is partially or completely visualized in 75% of wrist joints studied and this fi nding could help exclude scapho-lunate dislocation or subluxation.

Imaging patellar complications after knee arthroplasty P. Melloni, R. Valls, M. Veintemillas, S. Pérez, I. Delgado, M. Prieto; Sabadell/ES Learning Objectives: To illustrate and describe complications affecting the patella in patients with total or partial knee arthroplasty. Background: We retrospectively reviewed 937 consecutive patients treated with total or partial knee arthroplasty in the last two years; 34 (1.42%) patients (22 women and 12 men) presented patellar complications. Mean patient age was 74 years (range: 59-90 years). All underwent plain-fi lm radiography periodically. In determinate cases according to the clinical symptoms, patients underwent US. Imaging Findings: The most common patellar complications after total or partial knee arthroplasty were: fracture (n=9), instability (n=13), dislocation or luxation (n=4), osteonecrosis (n=5), infection (n=2), erosion (n=2), impingement on the prosthesis (n=3), patellar or quadriceps tendon tear (n=3), and loosening or rupture of the patellar prosthetic button (n=5). The mean interval from total knee replacement to patellar complication was 5 years and 7 months (range: 5 months-14 years). Conclusion: Patellar complications following knee arthroplasties are generally uncommon but often of potential clinical signifi cance. Plain fi lms are essential for the evaluation of patellar complications after surgery and should be the initial imaging study performed. Careful attention to initial prosthesis placement and comparison of follow-up images will allow subtle abnormalities to be detected in patellar complications. US may have a special role in the evaluation of soft-tissue structures around the patella.

Superfi Purpose: Fat-suppressed three-dimensional (3D) spoiled gradient-echo (SPGR) MR imaging has been described to be accurate for detecting 50% or greater cartilage defects. The purpose of this study was to determine the accuracy of sagittal fat-suppressed 3D SPGR imaging for detecting superfi cial cartilage defects of the medial femoral condyle. Methods and Materials: Fifty patients who had arthroscopically confi rmed cartilage defects by an arthroscopist and had MR imaging were included in this study. Sagittal fat-suppressed 3D SPGR MR images were retrospectively reviewed by a radiologist. Cartilage thickness was graded: Grade 0, normal; grade 1, abnormal signal without a contour defect; grade 2, less than 50% reduction of cartilage thickness; grade 3, 50% or greater reduction of cartilage thickness; and grade 4, full-thickness cartilage defect. Results: After arthroscopy, there were 68 cartilage defects in the medial femoral condyles: grade 2 (n = 21), grade 3 (n = 37), and grade 4 (n = 10). After fat-suppressed 3D SPGR imaging, cartilage defects in the medial femoral condyles were graded as follows: grade 2 (n = 26), grade 3 (n = 33), and grade 4 (n = 9). Sensitivity, specifi city, and accuracy for grade 2 cartilage defects were 90% (19/21), 85% (40/47), and 87% (59/68), respectively. Cartilage grading showed a signifi cant correlation between fat-suppressed 3D SPGR imaging and arthroscopy (r =.80, P <. 001, Spearman's correlation). Conclusion: Sagittal fat-suppressed 3D SPGR MR imaging is accurate for diagnosing superfi cial cartilage defects. Thus, it is helpful for planning treatment that could be different between early and advanced cartilage defects.

Direct and indirect MR arthrography: Advantages and disadvantages T.A.A. Macedo 1 , L.P. Souza 2 , L. Farage 2 ; 1 São Paulo/BR, 2 Uberlândia/BR (tamacedo@hotmail.com)

Learning Objectives: To demonstrate the pros and cons of direct and indirect magnetic resonance arthrography (MRA). Background: Direct MRA (dMRA) with injection of gadolinium (Gd) diluted in saline solution can be useful for evaluating certain pathologic conditions in the joints. It is most helpful in the shoulder; especially for outlining labral-ligamentous abnormalities and distinguishing partial-thickness from full-thickness tears in the rotator cuff; but it can be also useful in other joints, demonstrating labral tears in the hip, showing tears of the collateral ligament of the elbow, identifying residual or recurrent tears in the knee following meniscectomy, and assessing the stability of osteochondral lesions in the articular surface of joints. Indirect MRA (iMRA) can be done when dMRA is inconvenient, or not logistically feasible. In this case, the MR images are acquired after an intravenous administration of Gd-contrast media. Between April 2005 and August 2006, we performed 29 dMRA and 44 iMRA in our institution. Procedure Details: The direct arthrographies were perfomed using fl uoroscopy and ultrasound guidance and about 12-15 ml Gd-diluted solution was injected in the shoulder. Indirect MRA was done after 10 ml (0.5 mmol/mL) intravenous injection of Gd-contrast media (Dotaren ® ,Guerbet Laboratories). All the examinations were performed in patients with rotator cuff, labral or SLAP lesions. Conclusion: Although iMRA is unable to fi ll the joint cavity, it does not require direct Gd-contrast media injection and it is superior to conventional MR imaging when there is minimal joint fl uid. In addition, intravenous injection allows demonstrating vascularized or infl amed tissue.

Evaluation of anterior cruciate ligament (ACL) autografts and allografts with magnetic resonance imaging (MRI) I. Tsifountoudis, I. Kalaitzoglou, A. Haritandi, I. Economou, A.S. Dimitriadis; Thessaloniki/GR (jtsif@mycosmos.gr)

Learning Objectives: Arthroscopic reconstruction of ACL is being performed with increasing frequency. Although the procedure is performed with good success rates, early and late complications have been documented. Our purpose is to demonstrate the normal appearance of the reconstructed ACL with MRI and to illustrate the diagnostic pitfalls and the postoperative complications. Background: Sixty-fi ve patients (58 males and 7 females; age range: 17-59) who had undergone ACL reconstruction using either autografts or allografts were referred to knee MRI (1.5 T) for ACL graft control, between July 2004 and September 2006. The imaging protocol included T1-weighted, proton density-weighted and T2-weighted fast spin-echo images and STIR images in all planes. If the graft was not optimally visualized, oblique sagittal T2-weighted images were obtained along the course of the graft. Finally, gadolinium was administered intravenously in 7 cases. Imaging Findings: Intact graft was depicted in 37 patients with continuous, homogeneous and low signal intensity. Signs of roof impingement were found in 10 patients. The graft fi bers were absent due to rupture in 18 cases. Localized arthrofi brosis (Cyclops lesion) was detected in 8 patients. Postoperative infection was diagnosed in 3 patients, migration of the interference screws in 3 cases and cystic degeneration of the graft was depicted in 2 patients. Thickening of the harvested patellar tendon was seen in 3 patients and "regeneration" of the hamstring tendons in 18 patients.

The knowledge of the normal MR appearance of ACL grafts and the recognition of their complications are crucial for the appropriate management of symptomatic patients.

Magnetic resonance imaging in chronic ulnar-sided wrist pain: Pictorial review J.S. Sawhney, A. Bajaj, R. Bhatt, K. Jeyapalan; Leicester/UK (jasdevsawhney@yahoo.com)

Purpose: Chronic ulnar-sided wrist pain management can be intimidating and confusing because of its vague and intermittent nature, complex anatomy and pathology and frustration that it induces in the patient and the doctor. This pictorial review attempts to present a spectrum of cases illustrating the anatomy and pathologies of this complex region as seen on MRI. Methods and Materials: MRI was done for 71 patients over a period of 3 years with chronic pain on ulnar side of wrist. 1.5 T scanner was used. Sequences used were T1 axial and coronal, PD Fat Sat axial and coronal, T2 sagittal and STIR sagittal. The abnormalities are categorised into osseous (bony and degenerative),

ligamentous, tendinous, infl ammatory neurologic and miscellaneous. Results: Fracture non-unions of the hook of Hamate (1), ulnar styloid process (1), Hamate contusion (1), Lunate AVN (2). Degenerative processes at pisotriquetral joint (4), midcarpal (triquetrohamate) articulation (2), distal radioulnar joint {instability (4) and synovitis (2)}. Ulnar impaction syndrome (7). Ligamentous injuries included Scapholunate (6). TFCC, Triangular fi brocartilage complex {tear (9) and degeneration (3)}. Tendinopathies and tensosynovitis noted in E4-E6 compartment (5), FCU (1) and Diffuse (3). Infl ammation and erosions (3) related to Rheumatoid disease. Neurologic processes such as entrapment of the ulnar nerve in Guyon's canal (1). Miscellaneous group includes Ganglia (4) and Neuroma (1). No abnormality was found in 13 patients. Conclusion: MRI extends the possibilities of evaluating chronic ulnar wrist pain. Its signifi cance lies in the non-invasive examination of various intraosseous as well as soft tissue abnormalities.

Evaluation of patellofemoral joint cartilage at high-resolution MR imaging using a microscopy coil: Comparison with conventional MR imaging S. Takao 1 , H. Nishitani 1 , T. Yamaguchi 2 , M. Uetani 2 ; 1 Tokushima/JP, 2 Nagasaki/JP (takaos@mue.biglobe.ne.jp)

Purpose: MR imaging using a microscopy coil provides high-resolution images, which can be useful in demonstrating early cartilage abnormalities. The purpose of this study is to evaluate its diagnostic accuracy in evaluation of patellofemoral joint cartilage abnormalities. Methods and Materials:We evaluated 44 patellofemoral joints (43 patients) with MR imaging using a conventional knee coil and a microscopy coil; T2-weighted images and fat-saturated proton-density-weighted images were acquired respectively. Retropatellar cartilage was divided into 9 parts and femoral cartilage into 3 parts, where the status of cartilage was graded into 0 (normal) to 4 (full thickness injury). The diagnostic accuracy was analyzed using surgical or arthroscopic fi ndings as a standard of reference. Results: In 528 parts of cartilage, accuracy of MR grading using a microscopy coil and a conventional knee coil were 0.924 and 0.915, respectively, when grade 1-4 was considered to be positive, and 0.990 and 0.994, respectively, when grade 2-4 was considered to be positive. In 31 parts with grade-1 surgically confi rmed cartilage lesion (superfi cial lesions, soft indentation and/or superfi cial fi ssures and cracks), MR grading were correct in 9 with a microscopy coil and in 3 with a conventional coil. However, no signifi cant difference was seen statistically in the accuracy of both techniques. Conclusion: This preliminary study indicated that high-resolution MR imaging using a microscopy coil could be useful in detecting early cartilage abnormalities. Further study is required to obtain a statistically signifi cant result. Learning Objectives: 1) To describe the MR imaging fi ndings in the patellar tendon-lateral femoral condyle friction syndrome. 2) To consider the patellar tendonlateral femoral condyle friction syndrome in the differential diagnosis of patients with anterior knee pain. 3) To identify the patellar tendon-lateral femoral condyle friction syndrome in order to make a correct treatment. Background: Patellar tendon-lateral femoral condyle friction syndrome is a rare cause of anterior knee pain related to the clinical entity of fat pad impingement. MR imaging can reliable identify this entity, showing the soft tissue edema in the infrapatellar fat body in the anterolateral aspect of the patellofemoral joint. Imaging Findings: Retrospective review of MR images in 51 knees (48 patients) with antero-lateral knee pain and a focal area of abnormal signal intensity in the inferolateral aspect of the patellofemoral joint was performed. Patients with a meniscal tear or ligamentous injury were retrieved to exclude these facts as the cause of knee pain. Abnormal patellar alignment was demonstrated in 28 knees. Patellar tendinitis was noted in 8 cases. Patellar confi guration type III of Wiberg was found in 22 knees. Conclusion: MR imaging allows identifi cation of changes in patients with patellar tendon-lateral femoral condyle friction syndrome that should be distinguished from other causes of anterior or lateral knee pain.

Utility of four-dimensional arthrography of the acetabular labrum applying motion-gated multislice computed tomography: Comparison with arthroscopy and Harris hip score N. Funabashi, S. Kishida, Y. Harada, H. Moriya, I. Komuro; Chiba/JP Purpose: To analyze the kinesis and morphology of the acetabular labrum (AL) non-invasively, we applied four-dimensional (4D) arthrography with motion-gated MSCT and compared the results with arthoscopy and Harris hip score (HHS). Methods and Materials: Forty-nine symptomatic patients (52 hips) underwent MSCT. Before CT acquisition, contrast material was injected into the hip joint. The subject performed reciprocating hip fl exion-extension at the same rhythm as a pulsation simulator. Then we performed mimic retrospective ECG-gating, that is "motion-gated", acquisition and were reconstructed to divide one movement into 10 segments. The kinematics and morphology of AL were evaluated on 4D fi lms and the fi ndings were classifi ed into three groups: stabilized, irregular, and eccentric motion. Hip arthroscopy was performed in 34 hips. Labral lesions were classifi ed into four groups according to morphologic features (intact, fray, tear, and detached). HHS was also calculated depend upon patient state at the examination. Results: Of 46 hips with adequate images, 15, 11, and 20 revealed stabilized, irregular, and eccentric motion, respectively. Of 16 without adhesive AL on arthroscopy, 6 had irregular (average 48 HHS) and 4 had eccentric motion (average 58 HHS) and HHS tend to be higher in the eccentric group than in the irregular groups on 4D CT. Conclusion: 4D arthrography of the AL applying motion-gated MSCT can reveal both kinetic and morphological changes of AL and can perform further stratifi cation in subjects with the American Academy of Orthopaedic Surgeons class 0, or 1 or without "detached" morphological fi ndings by arthroscopy.

Impact of whole-body MR in the assesment of extension and follow-up of hemophilic artropathy R. Domínguez, C. Altisent, S. Gispert, X. Merino, V. Pineda; Barcelona/ES (16966rdo@comb.es)

Purpose: The hemophilic artropathy (HA) is a progressive osteoarticular disease presumed to result from intra-articular and periarticular hemorrhage. The aim of this study is to defi ne the role of the Whole-Body MR (WB-MR) in the assessment of extension, degree of joint involvement, and follow-up of the HA.

In this prospective study, we performed a WB-MR performed in 35 patients with HA and prophylactic treatment. MR protocol included T1-SE, STIR, and GRE-T2 in the coronal and axial planes using several coils. The parameters evaluated were: 1) involvement of the important joints (shoulders, elbows, hips, knees, ankles), 2) bone or muscle-tendinous involvement (muscular atrophy, muscular haematoma, pseudotumor), and 3) other osteoarticular lesions not related to HA. The extension and degree of HE were classifi ed according to the European Score. Results: In one third of the patients, the WB-MR detected HA in other joints not detected clinically, as synovitis, hemosiderin deposits or early artropathy. One third of the patients with clinical history of hemarthrosis of repetition did not show articular involvement or hemosiderin deposits by MR. Other musculoskeletal pathologies not related to HA were identifi ed in 50% of the patients (meniscopathy, femoroacetabular impingement, labrum disease, avascular necrosis, fi brous defects), being important in order to stablish differential diagnoses.

The WB-MR is a new useful imaging technique for the estadifi cation and follow-up of HA. It allows the evaluation of the response to the prophilaxis and treatment of the disease. It is also helpful for the differential diagnosis with intercurrent osteoarticular pathologies.

MDCT Background: Functional imaging might increase the role of imaging in muscular diseases, since sole assessment of muscle morphology reveals non-disease-specifi c results. Intact sodium homeostasis is crucial for tissue viability. Pathological changes of sodium homeostasis can be found in various clinical diseases, such as infarction, infl ammation, neoplasia, and muscular channelopathies. The implemented three-dimensional radial 23 Na MRI technique detected validly the tissue's sodium content. The acquisition time of 10 minutes and direct reconstruction of images and archiving them in PACS enabled a clinically feasible examination protocol. Imaging Findings: 23 Na MRI delivers reproducible data on sodium content within skeletal muscles. In various sodium channelopathies, 23 Na MRI detects intracellular sodium accumulation that is associated with muscle weakness and stiffness. Also, the benefi cial effects of blocking the pathologic sodium channels by a dedicated medication can be quantifi ed. Results of 23 Na MRI in vivo correlate signifi cantly to both electrophysiological in-vitro data of muscle fi bers derived from biopsies and muscle weakness in patients with sodium channelopathies. Furthermore, 23 Na MRI detects altered myocellular sodium content in other ion channelopathies and dystrophic myopathies, as well as altered muscular sodium signal in acute autoimmune myositis. Conclusion: 23 Na MRI can quantify skeletal muscle sodium homeostasis and is a promising functional imaging method, especially for muscular channelopathies.

The correlation between sonography and disease severity in carpal tunnel syndrome E. Alimoglu, H. Ozcanli, S. Dogan Bayraktar, A. Apaydin, S. Tuzuner, E. Luleci; Antalya/TR (ealimoglu@akdeniz.edu.tr) Purpose: To investigate the correlation between sonographic fi ndings and severity of carpal tunnel syndrome (CTS). Methods and Materials: 118 wrists of patients with CTS symptoms were included in our study. After clinical examination and electrodiagnostic study (ENMG), sonography was performed in patients by a radiologist unaware of the physical examination and ENMG results. The wrists showing both positive clinical fi ndings and ENMG results were diagnosed as CTS. The cross-sectional area of median nerve was measured at the level of the psiforme bone in sonography and the measurements over 10 mm² were accepted in favor of CTS. The disease was categorized into three groups according to ENMG Results: mild, moderate and severe. The difference between the mean sonographic area values of the three severity groups was investigated to estimate disease severity. Results: Fifty-four wrists had positive clinical examination and ENMG results. The mean area was 14.9±5.7 in these cases. The median nerve area was measured under 10 mm² in 7 cases. The sensitivity of sonography in the diagnosis of CTS was 87%. The mean area of the median nerves was 11.1±3.4 mm², 14.4±4.5 mm², and 19.2±5.9 mm² in mild, moderate and severe groups, respectively, and the difference between them was statistically signifi cant (p=0.000, Kruskal-Wallis analysis). Conclusion: The diagnostic usefulness of sonography in CTS has been clearly shown previously. However, little attention has been paid to the correlation between sonographic fi ndings and severity of disease. In addition to its high sensitivity in the diagnosis of CTS, sonography may also be helpful in estimating disease severity.

The aim of this study is to analyze and correlate the size and MR imaging signal features of aggressive fi bromatosis with its behaviour. March 1985 and December 2005, 27 patients with at least two consecutive MRI examinations and no surgery or radiation therapy in between were recorded. They underwent 107 MRI examinations of 47 lesions, of which 29 were medically treated, while the remaining 18 did not receive any drug administration. Each lesion was studied by size and signal changes in time on T2-injected and/or T1-weighted sequences. For size, we used the RECIST criteria. We classifi ed the signal in six increasing classes, and then we established the related variations in the time.

Results: Seventy-nine per cent of lesions in the treated group and 82% in the not-treated group maintained size stability. The initial signal of stable or increase in size of lesions was most frequently high. There was a high rate of signal stability in time, whatever the initial signal and size changes were. The size changes were not correlated with the initial MR signal. Only in the treated group, 3 decreases in size associated with signal decrease were observed. Conclusion: Fibromatoses are a group of soft-tissue tumors with variable characteristics on MRI, but it is not possible to predict their behaviour from MRI signal.

Assessment Background: Functional imaging might increase the role of imaging in muscular diseases, since sole assessment of muscle morphology reveals non-disease-specifi c results. Perfusion, i.e. the blood fl ow per tissue and time unit including capillary fl ow, is an important functional parameter. Pathological changes of skeletal muscle perfusion can be found in various clinical diseases, such as degenerative or infl ammatory myopathies. Contrast-enhanced ultrasound allows for a sensitive detection of microvascularity in real-time. Quantifi cation of perfusion is achieved by analyzing replenishment kinetics of the contrast agent. Also, the effects of training schemes on muscle microcirculation can be assessed for separate muscle groups. Imaging Findings: Contrast-enhanced ultrasound delivers reproducible perfusion data in volunteers. CEUS visualizes exercise-induced hyperperfusion and can separate well-trained subjects from un-trained subjects. CEUS-derived perfusion results in vivo correlate signifi cantly to capillarization in biopsies from these muscles. Furthermore, CEUS detects increased microcirculation in histologically proven acute autoimmune myositis with comparable accuracy as MRI and additionally increases specifi city in diagnosis of myositis when a muscle edema -as such a non-specifi c fi nding -is evidenced by MRI. Moreover, the effects of muscle degeneration on microcirculation can be assessed. Conclusion: Contrast-enhanced ultrasound allows valid quantifi cation of skeletal muscle perfusion and is a promising functional imaging method for various myopathies.

Gas Learning Objectives: To illustrate the wide spectrum of causes of subcutaneous emphysema in the emergency room. To show the key fi ndings on CT and plain radiograph. To discuss the differential diagnoses. Background: Gas in soft tissue is a relatively common sign at the emergency room. It has a great importance due to its broad casualty, some of them totally benign, but others potentially lethal. We retrospectively reviewed the imaging fi ndings of patients with subcutaneous emphysema from our database of emergency pathology. We analysed the origins and the associated features. Imaging Findings: Gas in soft tissue was found associated to traumatic, iatrogenic (surgical procedures, injection), or infectious causes (necrotizing fasciitis, Fournier gangrene). It also was found associated with thoracic pathology causing pneumothorax and pneumomediastinum, and abdominal pathology related to intraperitoneal and retroperitoneal gas. Diagnostic diffi culties and differential diagnoses are emphasized.

Radiologists must be aware of anomalous gas in soft tissue, because it may be the main or even unique sign to lead us to search the underlying pathology, which can be lethal.

Multi-detector-row CT of the muscles by using volume rendering techniques L. Saba, G. Caddeo, M. Atzeni, F. Corrias, D. Ribuffo, G. Mallarini; Cagliari/IT Learning Objectives: To analyze the mathematical concept to obtain VR images to defi ne the muscles. To learn the CT technical parameter to be used, as well as the slice thickness, increment, mAs and kVs. To understand the current indications for performing multi-detector-row CT study of the muscles underlining radiation exposure, cost and diagnostic effi cacy Background: Multi-detector-row CT, by using fast scanning and thin collimation can obtain near-isotropic voxels, producing an excellent image detail. Moreover, with the use of post-processing procedures it is possible to obtain volumetric images with an impressive visual impact (dissection-like images). With the use of correct techniques, by using in particular Volume Rendering (VR) reconstruction, it is possible to defi ne body musculature and to identify pathological alterations. The aim of this education exhibit is to describe how it is possible to obtain a correct visualization of the body muscles and to show volume rendered images that are possible to obtain. Procedure Details: We studied 12 patients by using a multi-detector-row CT (MDCT). Data obtained were re-processed and we obtained Volume Rendered Images. For each patient, we generated multiple VR reconstructed images in order to defi ne the better strategies to evaluate different types of muscles. Conclusion: MDCT can obtain excellent visualization of the superfi cial musculature; in particular, it defi nes with accuracy normal anatomy.

Hibernoma: Review the MRI imaging in eleven patients M. de Albert 1 , S. Martínez 2 , J. Narváez 1 , R. Mast 1 , E. Carreño 1 ;

Learning Objectives: Hibernoma is a rare benign soft-tissue tumour of brown fat cells. We describe the MR imaging fi ndings of eleven patients. Background: Cases were retrospectively identifi ed from the pathology database of two tertiary referral hospitals. Patient age, sex and duration of symptoms were recorded. We retrospectively reviewed the MRI of eleven patients with histologically proven hibernoma. Imaging Findings: Patient group consisted of seven females and four males, with an average age of 35 years (range 25-63 years). Six lesions were located in the thigh, one in the chest and four in the upper limb. Six of the lesions were intramuscular, three were intermuscular and two were located in the subcutaneous fat. The majority of the cases demonstrated MR fi ndings of a well-defi ned, heterogeneous mass, slightly or clearly hypointense to subcutaneous fat, with prominent thin low signal bands on T1 W SE images. The lesions failed to suppress fully on STIR or fat-saturated T2-weighted images. Six of the seven post-contrast studies evidenced signifi cant enhancement within the lesion.

The MR fi ndings described should lead to consider this rare diagnosis in the assessment of an atypical fatty mass on MRI.

Radiologic-pathologic correlation in fat tissue tumours of the extremities F. Sandomenico, O. Catalano, F. Fazioli, A.R. De Chiara, A. Nunziata, A. Siani;

Learning Objectives: To give a comprehensive accurate guide of US, CT and MRI fi ndings in various types of soft tissue lipomatous tumours of the extremity, with pathologic correlations during and after surgery. Background: Soft tissue tumours with prevailing fat tissue areas are lipomas, lipoblastoma, hibernoma and liposarcoma. Liposarcoma is the second most common type of soft tissue sarcoma (10-35%). Its histological subtypes are categorised as: well differentiated, dedifferentiated, myxoid, allomorphic and mixed type. Procedure Details: The lesions illustrated are identifi ed with relative ease on CT and MRI, due to the typical density/signal of the fat. Lipomas, however, can reveal small non-fat density/signal areas; in these cases vigilance is necessary. In malignant lesions, one can usually detect fatty areas that allow the diagnosis. In these cases, the non-fat areas, on which the biopsy is to be directed, are picked up with imaging. Special attention should be focused on the density/signal intensity in tumour nodules and septation. Myxoid liposarcomas have some particularity such as intramuscular position, pseudocystic aspect with peripheral enhancement, small solid nodules, or septa containing fat.

The knowledge of the pathological and surgical substrate of the lipomatous tumours of the extremity soft tissues constitutes the base for the diagnostic imaging assessment and is fundamental for optimal patient management.

The role of ultrasonography in patients with radial nerve pathology: Comparison with magnetic resonance and surgery C. Bertocchi, S. Colopi, R. Adani, P. Torricelli; Modena/IT (clatommy@fastwebnet.it)

Purpose: To evaluate Ultrasonography (US) accuracy in identifying radial nerve (RN) morphology and related pathologies compared to Magnetic Resonance (MR). Methods and Materials: Fifteen patients with NR paralysis (6 had expansive and 9 traumatic pathology) were examined with radiography, electromyography, US (Siemens-Sequoia; linear probe 10-15 MHz) and MR (Philips Intera 1.5 Tesla). Surgical evaluation was performed in 10 patients. US and MR parameters evaluated were: identifi cation, thickness, integrity and structure of the RN. Results: Five patients had a spontaneous recovery of RN paralysis. In the remaining 10, US identifi ed correctly RN morphology, thickness, structure and anatomical relationship, compared to surgical evaluation. RM was unable to identify the RN in 5 cases because of the metallic material artefacts. In traumatic and expansive pathologies, mean RN thickness was 4.4 mm and 1.4 mm, respectively; the ecographic structure was ipoechoic with loss of the fascicolated normal pattern in traumatic lesions while normal in expansive ones. Conclusion: US and MR are both useful for the diagnosis of RN pathologies. US is a dynamic, comparative and brief examination, useful when metallic material obstacles are used in MR evaluation. US, therefore, is also useful in planning surgery and in the follow-up.

Radiological Background: GCTTS is part of a group of benign proliferative lesions of the sinovium of the joint, bursa and tendon sheath. It represents the most common of this group of lesions, both in its localized and its diffuse form. Procedure Details: We studied retrospectively 24 patients with GCTTS localized in hands (23 had a single tumor and the remaining patient had a multifocal involvement). Diagnosis was made by means of excisional biopsy. In all cases, plain fi lms and MRI were performed. Size, shape, localization and osseus involvement were analysed, as well as MRI characteristics such as signal intensity and contrast enhancement. Cases of relapse after surgery were also recorded. Regarding MRI, in T1 weighted images all tumors were homogeneous and isointense, but they were more heterogeneous and predominantly hipointense in T2. After intravenous paramagnetic contrast administration, a homogeneous enhancement was demonstrated. In all cases, gradient echo sequences showed very low intensity areas. Surgery was performed in every patient. In 6 of them, local relapse was detected. Conclusion: GCTTS is one of the most frequent soft tissue masses of the hand, second in frequency only to ganglion. We are obliged to suspect it in every case of hand tumor, specially if it is localized in the fi ngers. MRI is useful in the diagnosis due to the characteristic fi ndings of the tumor.

Benign peripheral nerve sheath tumors in the pelvis: CT and MR fi ndings Z. Jiang, W. Peng, T. Yang; Shanghai/CN (issyjiang@yahoo.com.cn)

Purpose: Benign peripheral nerve sheath tumors (BPNSTs), which include neurilemomas and neurofi bromas, arise in the pelvic space are relatively uncommon. The purpose of our study was to characterize the CT and MR fi ndings of pelvic BPNSTs. Methods and Materials: CT and MR images of 16 patients with a pathologically proven pelvic BPNST (11 neurilemomas and 5 neurofi bromas) were retrospectively reviewed. The following morphologic characteristics were evaluated according to tumor shape, size, position, margin, homogeneity and invasion into adjacent structures. When MRI had been performed, signal intensity and the pattern of enhancement were also assessed. Results: All 16 pelvic BPNSTs were round in shape, with well-defi ned margins; the mean diameter was 8.2 cm (4-13 cm); they were usually located in the presacral region (12/16). Tumors were typically heterogeneous with cystic change (11/16), but centrally massive cystic attenuation was more common in neurilemomas than in neurofi bromas (8/11 vs 0/5). In 2 cases, there was smooth expansion of a sacral foramen with marginal sclerosis (1 in each group). 7 patients underwent MRI, T2WI showed hyperintense cystic areas and solid areas of mixed intensity. On CT or MRI contrast-enhanced images, peripheral enhancement was apparent in 7 of 11 neurilemomas, whereas irregular enhancement was evident in 4 of 5 neurofi bromas. Conclusion: Both pelvic neurilemomas and neurofi bromas are typically round, large, well-circumscribed, heterogeneous tumors that are located in the presacral space. They can occasionally cause bony changes in the sacrum, but do not invade adjacent structures. Centrally massive necrosis or peripheral enhancement favors the diagnosis of a neurilemoma. Learning Objectives: To illustrate the spectrum of typical imaging fi ndings of Charcot's spine and to discuss the main differential diagnoses such as infectious spondylodiscitis.

Background: Neuropathic arthropathy of the spine is a rare destructive condition of the spine, which is secondary to the loss of the protective proprioceptive refl exes. Infection must be considered as a possible differential diagnosis in case of a Charcot's spine with destructive lesions. Imaging Findings: Plain fi lms, CT and MRI with gadolinium injection are useful. This destructive process involves the disc space, the vertebral bodies and the facet joints. The thoracolumbar junction and lumbar spine are most frequently affected, and one or more vertebral segments may be involved. Sclerosis or osteolysis may predominate, and the spinal changes are often initially thought to be due to vertebral osteomyelitis or metastasis. Osseous fragments typically extend beyond the confi nes of the vertebral body margins into the musculature and the spinal canal. Bone debris and effusion may result in a paraspinous mass containing calcifi cations. However, solid epidural masses are typically lacking. The presence of vertebral body sclerosis and osseous fragmentation are further imaging fi ndings that help differentiate neuropathic spine from other processes. Conclusion: Background and imaging are suggestive of the diagnosis. Closed needle and even open surgical biopsies are often necessary to fi nally confi rm the Charcot's spine and exclude infection.

Spontaneous vertebral fracture -investigation with conventional and diffusion MR imaging T. Gerukis, M. Tsoukala, A. Fotiadou, E. Vafeiadis, V. Kalpakidis, P. Palladas; Thessaloniki/GR Purpose: The spine is the most common location of bone metastases in patients with primary malignancy, and also of benign osteoporotic fractures, especially in the elderly and in those who receive long-term steroid therapy. Conventional imaging techniques cannot always differentiate benign from malignant lesions. Those can be better distinguished with the addition of tissue-apparent diffusion coeffi cient (ADC) measurements.

A total of 51 acute vertebral body compression fractures were found in 35 patients. Twenty-eight fractures in 19 patients were due to osteoporosis (due to age or therapy), whereas 23 fractures in 16 patients were histologically proven to be due to malignancy. Signal intensities on T1-weighted, short tau inversion recovery (STIR) and diffusion-weighted images were compared. ADC values of normal and abnormal vertebral bodies were calculated. Results: Benign acute vertebral fractures were hypointense and malignant acute vertebral fractures were hyperintense with respect to normal bone marrow on diffusion-weighted images. Mean ADC value was 0.51 (±0.23) x 10 -3 mm 2 sec -1 in metastatic acute vertebral fractures and 1.33 (±0.47) x 10-3 mm 2 sec -1 in osteoporotic acute vertebral fractures. These values were signifi cantly different. Conclusion: Diffusion-weighted MR imaging with quantitative evaluation of ADC values allows the distinction of benign from metastatic vertebral compression fractures. It is a procedure that provides valuable additional information, and we believe that it must take its place in everyday clinical practice.

MRI presents no immediate impact on lumbar spine degeneration in adolescent elite athletes versus non-athletes H. Hoff, I. Platzek, U. Reuter, K.-P. Günther, M. Laniado, P. Aikele; Dresden/ DE (hansjoerg.hoff@uniklinikum-dresden.de) Purpose: Degenerative spine abnormalities start developing early in life and are frequent even among adolescents. The effects of sports on lumbar degeneration in adolescents have not been comprehensively evaluated yet. The aim of this prospective study was to compare the degree of spine degeneration in adolescent athletes and non-athletes.

The lumbar spines of 111 adolescent elite athletes (56m, 55f; mean age: 15.4 years) and 20 non-athletes (10m, 10f; mean age:15.0 years) were examined using MRI. The lumbar spine examination was performed with a 1.5 T MRI scanner (Somatom Sonata, Siemens, Germany). Sagittal PD, T1, T2 and TIRM images and transverse T2 images were obtained. Two radiologists evaluated the images using a previously designed checklist.

Results: The prevalence of pathologic fi ndings varied widely in both groups. 73% of the athletes and 70% of the comparison group were affected by protrusions. 27.9% of the athletes showed spondylarthrosis (non-athletes: 20%). Decreased signal intensity of vertebral discs on TIRM images was found in 30.6% of the athletes (non-athletes: 30%). There were no cases of nerve root or spinal compression. The chi-square test was used for statistical evaluation. There were no signifi cant differences concerning the most common degeneration signs (protrusions, disc degeneration and spondylarthrosis).

The authors conclude that active participation in sports does not have a signifi cant immediate impact on spine degeneration in adolescents. However, in order to evaluate the long-time effect of sports on the spine, further follow-up studies are necessary.

Multi-slice CT of spinal metal implants: Pictorial essay H.R. Cairns, J.M. Elliott, P. Archbold, R.J. Winder; Belfast/UK (heathercairns@greenpark.n-i.nhs.uk) Learning Objectives: To recognise the difference in beam hardening artefact, produced by steel and titanium spinal implants, on multi-detector spiral computed tomography (MDCT). To appreciate the effect of data acquisition parameters on the degree of artefact. To appreciate the effect of 3 different reconstruction kernels on the appearance of titanium metal artefact. To learn how to reduce the degree of artefact by altering MDCT scanning and reconstruction parameters. Background: Steel and titanium metals are commonly used in spinal surgery with signifi cant impact on post-operative CT image quality. The artefact is due to beam hardening and it appears as streaking with signifi cant change in local CT number values. The streaking artefact can seriously detract our ability to visualise pathology in proximity to the implant, for instance, nerve root irritation, remaining bone/disc protrusion. Procedure Details: Steel and titanium pedicle screws were positioned in a "dry bone" lumbar spine model. This was immersed in water. The model was scanned in a Siemens (Erlangen) 16-slice MDCT scanner. Twelve data sets were obtained using combinations of slice thickness (1.5, 0.75, 0.75 head protocol, and 0.6 mm) and reconstruction kernels (smooth, medium and sharp). Artefact in each data set was assessed at the CT workstation and personalised workstation, using identical window settings, CT numbers and a line profi le technique. Conclusion: A signifi cant difference was measured between steel and titanium pedicle screw artefact. The images presented have demonstrated that beam-hardening artefact can be reduced depending on the combination of slice collimation and kernel setting.

Biomechanical model to assess the fl exion/extension mobility of the lumbar spine: Consideration of soft tissue artifacts A. Curti, F. Perona, G.L. Ciavarro, G.C. Santambrogio, G. Andreoni, G. Castellazzi, G. Cornalba; Milan/IT Purpose: Skin-based measures obtained through optoelectronic system maybe a good technique to assess the functionality of the lumbar spine. However, soft tissue artifacts (STA) may be a signifi cant and relevant problem to accurately measure the mobility of the spine and so they had to be considered. Methods and Materials: 10 healthy people participated in the experimental setup. Twenty-four markers (pills of oil E vitamin) were attached onto the skin in correspondence to vertebral reference points. Six static fl exion/extension postures were acquired through a vertical MRI (vMRI). Then a fl exion/extension movement of the lumbar spine was acquired through an optoelectronic system. The estimation of the position of vertebral Center of Rotation (CoR) together with the knowledge of STA (obtained from previous studies) allowed the development of a new biomechanical model to assess the mobility of the lumbar spine. Finally these data were validated comparing the results of the biomechanical model with a gold standard (vertebral mobility through vMRI).

Results: This biomechanical model shows a metameric error of 2.7° ± 0.6° and global error of 9.1° ± 3.5°. These data are very good with respect to the traditional methods assessing the lumbar spine mobility with a mean error reduction of about 50%.

Conclusion: This biomechanical model estimates well the lumbar fl exion/extension mobility starting from 3D kinematic data acquired through an optoelectronic system, some anthropometrical characteristics, the relations of STA (previously found) and the CoR (here estimated). So it may be a useful instrumentation to assess the functionality of the lumbar spine. B D E F A G 

Ultrasound-guided interventional procedures in the foot and ankle M. Vlychou, J. Teh; Oxford/UK (mvlychou@doctors.org.uk) Learning Objectives: This pictorial illustration of ultrasound-guided interventional procedures of the foot and ankle will review the indications, technique and possible complications. Background: Foot and ankle pain, both acute and chronic, are common indications for clinical investigation due to degenerative, infl ammatory or osseous pathology and sport injuries. Ultrasound is an imaging modality that can be applied not only for the detection of the underlying cause of the problem, but also more importantly as a means of therapeutic and diagnostic intervention. 

Misinterpretation of radiographs by emergency physicians: How big is the problem? Y. Thian, M. Mateo, S. Tay; Singapore/SG (ylthian@gmail.com)

Purpose: To evaluate the rate of discrepancies in radiographic interpretation between emergency physicians and radiologists. The pattern of commonly missed radiographs and the nature of clinically signifi cant interpretation discrepancies leading to a change in management or adverse outcome were also studied. Methods and Materials: All radiographs obtained in our emergency department from January through February 2006 were fi rst interpreted by ED physicians and compared with the formal radiology reports. Discrepant interpretations were marked for further study and classifi ed into one of four categories: false-negative interpretation by ED physicians, false-positive interpretation by ED physicians, false-negative interpretation by radiologists and false-positive interpretation by radiologists. Discrepancies that necessitated intervention and adverse outcomes were also recorded from the clinical summaries. Results: Of the 7309 radiographic examinations generated during the study period, there were 152 (2.1%) false-negative misreads by the ED physicians and 115 (1.6%) overreads. Only 22 examinations (0.3%) necessitated an alteration in clinical management as a result of the misreads. Three adverse events were recorded during the study period as a result of radiographic misinterpretation, all of which were cervical spine radiographs. The most frequent type of false-negative interpretation was the chest radiograph. Conclusion: Only a small portion of radiographic misinterpretations by ED physicians necessitated a change in management.

Ultrasonography In this exhibit, we show the topographic anatomy of the brachial plexus and its distal branches, with special attention to its anatomical relationships and its ultrasonographic appearance. There are three anatomical regions to approach the brachial plexus: a) supraclavicular region, b) infraclavicular or anterior region of the shoulder and c) axilar region or root of the arm. We show the topographic anatomy of each of these three regions, and the different puncture techniques recommended for each area. Conclusion: Brachial plexus punctures allow the locoregional blockade of several regions of the upper limb. US enables to guide the puncture with great safety, diminishing complication rates and undesired side effects, such as nerve lesion or the intravascular injection of local anesthetic drugs. Lesions were classifi ed as hypointense, isointense or hyperintense. Results were compared with fi nal diagnosis established by pathologic examination (n= 5). Statistical analysis was performed with Student's t-test. Results: Benign bone tumours and soft tissue lesions were iso-to hypointense to adjacent normal bone marrow. Malign bone and soft tissue tumours and benign bone lesions including infection and aseptic necrosis were hyperintense to normal bone marrow. Malign tumours and infectious processes had positive contrast ratios, whereas benign musculoskeletal tumours had negative values (p < 0.001). Conclusion: PSIF sequence may allow differentiation of malign and benign musculoskeletal lesions. Malign tumours show hyperintensity, probably owing to altered water proton mobility in neoplastic tissue. Benign lesions, except infection and aseptic necrosis of the bone, show hypointensity, refl ecting free water proton mobility. In infectious processes, hyperintensity may be attributed to infl ammatory cells, mucoid and proteineous matrix decreasing free water fraction in the interstitial space.

Normal sonographic anatomy of the foot with MRI correlation G. Ansede, J.C. Healy, J.C. Lee; London/UK (gonzaloansede@yahoo.com)

Learning Objectives: To demonstrate normal sonographic anatomy of the foot with emphasis on short foot ligaments using schematic drawings and MR imaging for correlation. Background: The oblique orientation of the foot ligaments and tendons can result in diffi culty identifying them on MR imaging. However, many of these structures can be identifi ed using high frequency sonography transducers. The four muscle layers of the sole of the foot. Conclusion: Sonography offers high resolution imaging of the tendons and ligaments of the foot. In addition, sonography is quick, relatively inexpensive, widely available and allows for dynamic evaluation of structures which can be easily clinically correlated at the time of scanning. However, sonography is operator dependent and optimal assessment can only be made with intimate comprehension of the normal sonographic anatomy.

Do radiologists need to report A&E trauma extremity fi lms? S. Hussain, J. Heron, L. Farrell, A. Ahmed; Birmingham/UK (drsh9@hotmail.com)

Purpose: Plain fi lm reporting still makes up a signifi cant proportion of the reporting work in radiology departments. Trauma extremity fi lms on patients admitted via the accident and emergency department constitute the signifi cant majority. With these fi lms being looked at by radiographers (red dotting fi lms), trauma juniors and/or senior doctors, is there still a necessity for reporting of these fi lms by radiologists? Previous published studies have shown that junior doctors reported as few as 32% of fi lms correctly. Methods and Materials: Retrospective analysis was made of all patients who presented through the accident and emergency department at Sandwell Hospital, Birmingham over two separate one-week periods. Extremity fi lms were identifi ed and the report in the notes made by the clinician was compared with the consultant radiologist report. Discrepancies were identifi ed and any fi lms where there was discord were double reported by another consultant radiologist to provide a "gold standard" report. Results: Sixty-four percent of the radiographs were agreed to be normal, 18% were agreed to be abnormal but 18% were abnormal, which were identifi ed by only one department. After double reporting, A&E had an error rate of 12%, with a false positive rate (identifying a fracture where none was present) of 23% and a false negative rate (missing a fracture where one was radiologically present) of 5%. Errors were greatest with the shoulders, elbows and ankle X-rays. Radiology had an error rate of 5%. Conclusion: Although A&E doctors have a high standard of reporting, with a low false negative rate, there is still a need for radiology to report all trauma fi lms.

Sonography of the musculoskeletal system: A how-to-do DVD Rom-based audiovisual guide G. Delimpasis, K. Chatzimihail, A. Michailidis, S. Faitaki, I. Bechrakis, A. Plagou, G. Adamakis, K. Pahou, P.S. Zoumpoulis; Athens/GR (echo@hol.gr)

Learning Objectives: 1. To outline basic US physics and US technology. 2. To present the examination technique of the musculoskeletal system. 3. To illustrate the main indications and limitations of the modality. 4. To present normal echoanatomy and correlate abnormal sonographic fi ndings with specifi c musculoskeletal disease. Background: Modern high-resolution sonography is increasingly employed in the diagnosis of musculoskeletal injury and disease. The present DVD Rom is based on a series of lectures focused on facilitating training and incorporates technical aspects of proper US examination with features of normal and diseased echostructure of the joints. Procedure Details: Individual topics include the fundamentals of US physics and technology, study of the shoulder (with particular focus on rotator cuff pathology), elbow, wrist and carpal tunnel syndrome, knee, as well as examination of the pediatric patient and US applications in non-traumatic musculoskeletal disease. Normal sonographic appearances are identifi ed and juxtaposed to abnormal features associated with specifi c joint pathology. Relevant Doppler fi ndings, aberrations during dynamic scanning and common artifacts are also discussed. Emphasis has been placed on delineating the signifi cance of appropriate transducer manipulation and selection of machine settings so as to optimize diagnostic results. "Real-time" video fi les are used to demonstrate the correct technique through the simultaneous screen display of transducer positioning and obtained US images. Furthermore, these "hands-on" sessions elucidate the merits of dynamic scanning. A bilingual approach has been carried out by complementing the main Greek text with English subtitles. Conclusion: Sonography is a valuable modality for musculoskeletal imaging, provided it is implemented meticulously.

Ultrasound suspicion and add useful additional information. Direct imaging of peripheral nerves is possible using cross-sectional modalities, such as ultrasound (US), computed tomography and magnetic resonance imaging (MRI). In experienced hands, US provides an economic, fast, noninvasive and accurate evaluation of the MN from the axilla to the distal branches. Imaging Findings: In this article, we will fi rst present the normal anatomy of the MN through schematic drawing and selected images from cadaveric dissections. Then, the technique of US examination and the normal US appearance will be illustrated. In the last part, representative US images with MRI correlations and schematic drawings will be presented to illustrate a wide spectrum of the pathologic conditions. Conclusion: US can effi ciently assess the normal MN and diagnose a wide variety of disorders. Accurate knowledge of the US anatomy and scanning technique is an essential prerequisite.

Tumors Conclusion: The incidence of scapular tumors is low. Bone tumors involving the scapula as the sole site constitute an uncommon fi nding, with few cases reported. Both benign and malignant neoplasms can be found. Since early diagnosis is crucial for prompt therapy, imaging plays an essential role. Plain radiograph is the primary modality in the diagnosis approach. However, computed tomography (CT) and magnetic resonance (MR) play a major role in establishing diagnosis and staging.

Extended fi eld-of-view sonography: Does this technique provide additional information to conventional B-mode images? F. Eksert, C. Yucel, S. Ozhan Oktar, N. Kadioglu, H. Ozdemir; Ankara/TR (cyucel@gazi.edu.tr)

Purpose: To compare the imaging fi ndings of lesions examined with B-mode and extended fi eld-of-view (EFOV) sonography and to demonstrate if EFOV technique provides additional information. Methods and Materials: Sixty patients (32 males, 28 females) (age range:1-83 years, mean age: 47±18.3 years) with 61 lesions were involved in the study. 21/61 (34%) of the lesions were localized in the musculoskeletal system, 19/61 (31%) were in the neck area, 15/61 (26%) were in the anterior abdominal wall, 2/61 (3%) were in the peritoneal cavity, 1/61 (2%) was in the scrotum and 1/61 (2%) originated from the brachial artery. All lesions were examined with both the conventional B-mode and EFOV sonography. The fi ndings were evaluated independently by two radiologists. Sonographic images obtained with each technique were scored for lesion characterization, and for simultaneous demonstration of the lesions and their relationships with surrounding tissues. Wilcoxon signed rank test was used for statistical analysis. Kappa scores were calculated to assess inter-observer agreement. Results: Wilcoxon test revealed that EFOV sonography was superior to B-mode imaging for both lesion characterization and for the determination of its relationships with neighboring structures (p=0.000). Kappa scores refl ected moderate to good inter-observer correlation (0.186-0.454). Conclusion: EFOV sonography is a practical and easily applied technique. This technique overcomes the problem of limited fi eld-of-view, which is one of the most important disadvantages of B-mode sonography. The simultaneous visualization of the lesions and surrounding structures in larger fi eld-of-views makes EFOV images more apprehensible compared with conventional B-mode images.

Is it necessary to review all casualty radiographs? S. Nayak, M. Chandramohan, C. Groves; Leeds, West Yorkshire/UK (sanjeevnayak@hotmail.com)

Purpose: To check for any discrepancies in the plain fi lm reporting by the A&E doctors when rechecked by a radiologist. To look into the incidence of signifi cant misses that altered the patient management.

The duration of the study was 30 days. A retrospective study was conducted at the Bradford Teaching Hospitals, looking at all the casualty radiographs that were double reported by the radiologists. Results: A total of 1122 A&E fi lms were reviewed by the radiologists. 1002 (89%) of them were agreed upon by the radiologists in correlation to the A&E diagnosis. 120 (11%) of the total were disagreed by the radiologists. 36 (3.2%) of these were considered as signifi cant misses. Out of 120 disagreed fi lms, 60 letters were sent by A&E to the GP. Of these, 18 needed further investigations 18 were recalled to the fracture clinic. The radiologists' reports on radiographs of the chest, face, skull, and wrist had the greatest effect on patient management. Reports on the radiographs of fi ngers, hands, shoulders, long bones, and toes seldom altered treatment. Purpose: Thrombolysis has been shown to improve the 3-month outcome of patients with ischemic stroke, but knowledge of the long-term effect of thrombolysis is limited.

The present study compares the long-term outcome of stroke patients who were treated with intra-arterial thrombolysis (IAT) using urokinase with the outcome of patients treated with aspirin. The modifi ed Rankin scale (mRS) was used to assess the outcome. One hundred seventy-three patients treated with IAT and 261 patients treated with aspirin from the Bernese Stroke Data Bank were eligible for the study. A matching algorithm taking into account the patients' age and stroke severity on admission (as measured by the National Institute of Health Stroke Scale, NIHSS) was used to assemble an IAT and an aspirin group. Results: One hundred forty-four patients treated with IAT and 147 patients treated with aspirin could be matched and included in the comparative analysis. The median NIHSS score was 14 in each group. At 2 years, 56% of the patients treated with IAT and 42% of the patients treated with aspirin achieved functional independence (mRS 0 to 2; P = 0.037). Clinical outcome was excellent (mRS 0 to 1) in 40% of the IAT and in 24% of the aspirin patients (P = 0.008). Mortality was 23% and 24%, respectively.

The present study provides evidence for a sustained effect of IAT when assessed 2 years after the stroke.

The Purpose: The aim of our work was to localize cortical areas involved in the processing of the visual stimuli with different complexities using fMRI.

In eight healthy volunteers (18-30 years old), conventional anatomical and fMRI were performed on 1.5 T MR scanner. We used echo-planar imaging. For visual stimulation, we used matrix from 10x10 Gabor elements. Gabor element is a sinusoid fading under Gauss law, which corresponds to receptive fi elds of primary visual cortex cells. In "simple" stimulus, most elements have preferred orientation. In case of "complex" stimulus, only a part of the elements have preferred horizontal or vertical orientation. The size, brightness and contrast of the stimuli were identical for chaotic and ordered patterns. Post-processing includes: (1) calculating statistical map with t-student criterion of more than 4, where hypothesis H 0 assumes that MR-signal intensity in rest is equal to activation intensity; (2) for the identifi cation of anatomical structures, the resulting maps were fused with the anatomical image and then both images were transformed to space of atlas Talairach. Results: "Complex" stimuli in comparison with "simple" stimuli caused activation on Brodmann fi elds number 7, 9 and 37. When a patient must choose the preferred orientation of elements, click the left or right button of the mouse to discriminate between "complex" and "simple" stimuli; "simple" stimulus causes activation in the middle frontal gyros (Brodmann fi elds number 9/10). Conclusion: Thus, "complex" stimulus causes additional activation in the parietal lobes. Cases of active observation demonstrate an additional activation locus in the prefrontal cortex, which presumably, refl ects the work of the "central executive mechanism".

Anatomy of the normal and pathological visual pathways: A DTI-fi ber tracking study A. Paniagua Bravo, L. Muñoz Almazán, J. Guzmán de Villoria Lebiedziejewski, G. Medrano Seoane, J. Crespo San José; Madrid/ES (alvpaniagua@yahoo.es)

Learning Objectives: MRI Diffusion Tensor Imaging (DTI) was performed in 7 patients and 3 healthy individuals in order to study the visual pathway (VP). Our purpose was to show its normal anatomy as well as the pathological changes in some diseases that involve it. Background: Diffusion Weighted Imaging (DWI) is a useful technique to obtain brain maps from the white matter tracts. Our study is focused on the assessment of the VP after performing DWI maps to visualize the different parts of the VP. When compared to the results in normal subjects, the pathological features in patients can be classifi ed into 3 items: 1) Diseases that lead to atrophy of the VP (ocular globe enucleation, multiple sclerosis, hypovitaminosis); 2) Displacement of the fi bers caused by entities with associated mass effect (tumors); 3) Infi ltrating lesions of the VP (neoplasms, pseudodotumoral demyelinitation plaques). Procedure Details: All the studies were performed on a 1.5 T MR unit by using a single-shot echo-planar imaging sequence (fl ip angle: 90º, TR: 2020, TE:68, NSA:6) with b =800 mm 2 /sec. This protocol was modifi ed in 3 patients in order to obtain a better visualization of the pathology (TR: 8474, TE: 68, NSA: 6). We also acquired an anatomical imaging 3D/DTI. Post-processing was made in a workstation using the Philips PRIDE software. We get 2D and 3D color maps from the VP. Conclusion: DTI is a useful technique to study the normal and pathological visual pathway. Post-thalamic fi bers are easy to map, whereas the visualization of prethalamic fi bers is possible with a specifi c DTI acquisition protocol.

B D E F A G unavoidable effect of brain radiation. We reviewed fi ndings of routine MRI in 41 cases of pathologically proven CRN. Background: It is imperative to distinguish CRN from recurrent tumor in order to avoid unnecessary antineoplastic therapy and to administer therapy appropriate for the CRN. There is no defi nitive imaging method to distinguish these conditions. We retrospectively reviewed all clinical cases of CRN identifi ed histologically at surgery from HFH in the past 15 years. Imaging Findings: Treated tumors included 34 gliomas, 5 metastases, 1 PNET and 1 ependymoma. Central necrosis (37) and cysts (24) were common. T1 hyperintensity without contrast administration was seen in 17 cases. The most common pattern of enhancement seen in 35 patients included ill-defi ned borders, lack of a nodular component, and a central "swiss cheese" appearance. Subependymal enhancement was present in 25 cases and corpus callosum enhancement was seen in 16. A pattern of enhancement in two adjacent lobes separated by the dura was seen in three cases. Brain atrophy was present in 29 and leukoencephalopathy in 19 patients.

: A "swiss-cheese" and ill-defi ned, non-nodular pattern of enhancement was most common. The high frequency of involvement of the corpus callosum and subependyma was unexpected, as these fi ndings are traditionally reported with tumor infi ltration. A pattern of enhancement in adjacent lobes separated by the dura is uncommon, but may be pathognomonic of CRN when the imaging changes are consistent with the radiation fi eld dosimetry.

Dural lesions mimicking meningiomas: A pictorial review D. Chourmouzi, G. Boulogianni, K. Manolakaki, K. Drevelegas, T. Zaraboukas, A. Drevelegas; Thessaloniki/GR (dchourm@hol.gr)

Learning Objectives: To describe a number of neoplastic and nonneoplastic entities that radiographically and clinically mimic meningiomas. To outline the pathological and imaging characteristics of these entities. Background: Intracranial dural-based lesions can be due to benign or malignant processes. Imaging characteristics cannot always discern between different pathologic conditions. A thorough clinical evaluation may reveal likely diagnostic possibilities. Procedure Details: An overview of the MRI characteristics of dural lesions is presented. There is also presentation of some pathologically proven lesions including solitary fi brous tumor, gliosarcoma, hemangiopericytoma, melanocytoma, Hodgkin's disease, plasmacytoma, infl ammatory pseudotumor, plasma cell granuloma, Rosai-Dorfman disease as well as metastatic carcinoma. The role of the advanced magnetic resonance techniques such as spectroscopy, diffusion and perfusion MR imaging is discussed. Conclusion: The differential diagnosis of dural-based lesions in the brain varies from incidental and benign to symptomatic and malignant. Careful vigilance in patient's history is essential. Awareness that such lesions involve the dura may facilitate preoperative recognition and, in some cases, preclude unnecessary surgery. Learning Objectives: 1. To review pathophysiology and diagnostic criteria of mitochondrial disorder. 2. To investigate various neuroradiologic fi ndings in children with mitochondrial disorder and, particularly, unspecifi ed mitochondrial encephalomyopathies. Background: Mitochondrial disorders are a heterogeneous group of clinical syndromes associated with abnormalities of mitochondrial energy metabolism. The impaired energy production results from the overall dysfunction of mitochondrial respiratory chain, composed of 5 enzymatic complexes embedded in the inner mitochondrial membrane. We investigated the various neuroradiologic fi ndings in 40 children with mitochondrial disorder, and correlated them with the biochemical defect in the mitochondrial respiratory chain complex. Imaging Findings: Children with mitochondrial disorder showed different patterns of brain MR imaging abnormalities. Rapid progression of atrophy involving all structures of the brain with variable involvement of white matter were found in 29 patients, and the patients with complex I defi ciency showed more severe changes in serial scans; T2 prolongation of basal ganglia, thalami, brain stem and cerebellum in 18 patients with complex I or IV defi ciency; predominant cerebellar volume loss in 3 patients with complex I or IV defi ciency; and encephalomalacia of globi pallidi in 2 patients with complex I defi ciency. Conclusion: Children with mitochondrial disorder showed different features on brain MR imaging from a combination of various defects of mitochondrial respiratory chain complex. Defects of different parts of the mitochondrial enzyme could result in the same abnormality on brain MR imaging, whereas identical biochemical defects could cause different imaging manifestations. Learning Objectives: 1. To illustrate the wide spectrum of intracranial lesions with ring enhancement on MRI. 2. To categorize these lesions according to imaging fi ndings on DWI and calculated ADC values. 3. To provide an easy-to-follow algorithm for the differential diagnosis of intracranial ring-enhancing lesions. Background: Ring enhancement is an unspecifi c MR fi nding occurring with a variety of aetiologies. It is most frequently encountered in neoplastic and infectious disorders, such as metastases, gliomas, and abscesses, but is also observed in vascular pathologies, such as resolving haematomas and infarcts. Because of the variable clinical course and prognosis of these diseases, an early and correct diagnosis is necessary for choosing the appropriate therapy. Procedure Details: We present the broad spectrum of intracranial lesions with ring enhancement on MRI with emphasis on the diagnostic impact of diffusion-weighted sequences and ADC values. Additionally, MR features that could be possibly helpful in distinguishing ring-enhancing brain lesions are discussed. Conclusion: DWI has recently shown promise in differentiating ring-enhancing lesions such as brain abscesses and malignant neoplasms. Combining the information of conventional MRI and DWI with ADC calculations, the correct diagnosis of ring-enhancing lesions can be achieved in a majority of cases.

The dynamic study of CSF circulation in hydrocephalic patients by means of magnetic resonance (MR): Semeiotic technique and case gallery L. Fortunelli 1 , V. Annibale 1 , F. Favano 1 , P. Car 1 , P. Spagnolo 2 , A. Stecco 1 , A. Carriero 1 ; 1 Novara/IT, 2 Monza/IT (lorenzofortunelli@virgilio.it)

Learning Objectives: To describe the methodological aspects and advances of the CINE PC technique for studying CSF. To present a case gallery for each type of hydrocephalus. To describe the MR semeiotics of this technique. Background: CSF fl ow was previously studied by means of CT, a lumbar puncture (tap test) or ventriculocisternography. Dynamic MR investigations are based on phase contrast sequence that provides quantitative and qualitative measurements of fl ow velocity and direction. The automatic planning of acquisition planes has recently become available. The indications for this examination are to characterise normotensive hydrocephalus and treated hydrocephalus. Imaging Findings: Thirty-fi ve examinations were carried out using 1.5 Tesla MR with an eight-channel phased array coil and cardiac trigger, and post-processing

software for quantitative analyses. Axial FLAIR and sagittal CSF DRIVE sequences were used to localise the aqueduct of Silvius, and axial CSF QF (fast spin-echo 2D) for the quantitative analyses. CSF PCA is a sagittal PC angiography used to visualise CSF fl ow. The post-processing analyses included the quantitative and qualitative data, with the creation of a CINE-RM that visualises the CSF circulation. The technique is optimised using "smartbrain".

The technique was feasible in 100% of cases, all of which showed concordance between the CINE PC images and clinical symptoms. The automatic planning method makes the technique easier to perform.

Virtual MR ventriculoscopy of the brain H. Sherif, A.E. Mahfouz; Doha/QA (sherifhanan@yahoo.com)

Learning Objectives: To introduce the technique of virtual magnetic resonance (MR) ventriculoscopy of the brain and to illustrate the ventriculoscopic appearance of the cerebral ventricles in normal persons and in patients with different diseases of the brain, which involve the cerebral ventricles. Background: The recent advances in three-dimensionally acquired and displayed MR images and the use of virtual endoscopic technique in image processing have enabled virtual endoscopic examination of the cerebral ventricles. The present exhibit illustrates the appearance of the normal anatomy of the lateral, third, and fourth ventricles and the appearance of lesions related to the cerebral ventricles from an endoscopic viewpoint. Procedure Details: Three-dimensionally acquired images of the brain have been performed by 3D fat-saturated T1-weighted turbo-FLASH (fast-low-angle shot) sequence covering the whole brain. Images have been reconstructed by virtual endoscopic technique (Colon, Wizard, Siemens, Erlangen, Germany). Conclusion: Virtual MR ventriculoscopy of the brain is a new technique of imaging of the cerebral ventricles, which may be useful in three dimensional evaluation of congenital and acquired abnormalities as well as abnormal masses related to the cerebral ventricles.

Continuously monitoring of the brain during severe insulin-induced hypoglycemia by diffusion-weightened MR imaging P. Purpose: Severe cerebral hypoglycemia with onset of neurological symptoms is frequently associated with reversible diffusion disturbances, which could be visualized as hyperintense lesions by diffusion weightened brain imaging particular in the splenium and the corona radiata region. This study is focused on the evaluation of hypoglycemic pathogenesis, especially with regard to the severity of insulin-induced reversible hypoglycemia. Methods and Materials: Seven volunteers received an i.v. bolus of 0.15 U per kg body weight short acting insulin inducing hypoglycemia, while the individuals were continuously evaluated by a 1.5 T scanner (Siemens Sonata). Diffusion-weightened echo planar sequences (4500/107 TR/TE) were obtained without interruption. Additionally, serum blood glucose levels were also continuously monitored using Glucostix test strips; further more serum blood specimen were sampled for later laboratory measurements. Examination was stopped as soon as serum glucose level was diminished to < 2.0 mmol/l or the subject wished to abandon the trial due to vegetative symptoms. Images were independently analyzed by two radiologist. Results: All subjects revealed a hypocglycemia < 3.0 mmol/l for at least 10 min, mean serum glucose level decreased down to 1.94 ± 0.4 mmol/l and one patient stopped examination at 2.6 mmol/l due to vegetative symtpoms. In the MRI diffusion images, no alterations pointing at an infl uence of cerebral diffusion could be observed in all individuals. Conclusion: Short-time severe hypoglycemia (< 10 min) does not induce visible changes in MRI diffusion imaging, suggesting long-time hypoglycemia maybe the relevant cause for observed reversible diffusion disturbance in MR imaging.

Primary Learning Objectives: To illustrate the spectrum of MR and proton spectroscopy fi ndings in primary lactic acidosis related to mitochondrial diseases in brain. To describe the advantages of proton MR spectroscopy evaluation. Background: Mitochondrial diseases constitute a complex and heterogeneous group of metabolic disorders caused by heritable abnormalities of the respiratory electron transport cascade. Although mitochondrial dysfunction manifests over a wide range of clinical expressions, it most often affects the muscle and brain, where dependence on oxidative energy metabolism is highest. The most common clinical features are muscle weakness, lactic acidosis and a broad range of neurologic defi cits. In this exhibit, we will analyse MR and proton spectroscopy fi ndings of primary lactic acidosis related to mitochondrial disease. Between January 1996 and January 2006, we analyzed MR and proton spectroscopy of 11 patients with lactic acidodsis and clinically suspected of mitochondrial disease. Procedure Details: Nine patients had lesions bilateral and simetrics, hyperintense on Flair and T2-weighted images and hypointense on T1-weighted images in brain stem and basal ganglia. Three of them had thalamic involvement too. Proton spectroscopy revealed elevated lactate and a N-acetylaspartate reduction, both in areas that appeared damaged. In 2 of 11 patients, MR was normal but proton spectroscopy showed similar fi ndings. Conclusion: Proton spectroscopy is a useful investigational tool in the study of mitochondrial diseases as it supplies additional information to that of conventional imaging, because it documents metabolic anormalies even in areas of the brain that appeared to be normal.

Observation of metabolic changes in tumour bed with proton MR spectroscopy in patients with primary gliomas during radiation therapy L. Zarudzki, B. Bobek-Billewicz, W. Senczenko, A. Idasiak; Gliwice/PL (lzarudzki@op.pl)

Purpose: To observe the time course of the proton magnetic resonance spectroscopy ( 1 H-MRS) changes in tumor bed, during radiation therapy, in patients with primary gliomas.

We followed 19 patients who received an external radiation therapy for primary gliomas for 6-9 weeks (mean: 51 days; median: 49.5 days). All patients underwent brain surgery prior to the radiotherapy. The patients received fractioned doses of 54 or 60 Gy in the lesion area. Each patient underwent single voxel spectroscopy (SVS TE=135; TE=30) before and just after the completion of the radiation therapy. The voxels of interest were chosen in the tumour bed, overlying the planning target volume (PTV). The following metabolite concentrations, normalized concentrations and their ratios were evaluated by the areas of the peaks after peak fi tting: Naa, Cho, Cr, Lac, Lip0.9/1.3, Glu+Gln, Ins. The spectra were verifi ed with LCModel. Results: After the completion of radiotherapy, we observed the increase in the normalized NAA concentrations and Naa/Cr ratio and the decrease in the normalized Cho, Glu+Gln, Lip[0.9] concentrations and Cho/Naa ratio.

The 1 H-MR spectroscopy has the capability of detecting early metabolic changes in the irradiated tumour bed after the completion of radiotherapy. The increase of Naa and decrease of Cho and Glu+Gln concentrations can be the result of the residual neoplasmatic infi ltrate's regression. The changes in other metabolite concentrations occurred, but were not signifi cant.

Atypical Imaging Findings: Unusual imaging features of meningiomas are shown, such as infrequent locations (intraventricular, intraosseu); cystic or fatty degeneration; large edema; ring enhancement; low-ADC values and increased permeability. We will also show cases that may be diffi cult to differentiate from meningiomas, not only tumoral (mesenchymal tumors, hemangiopericytoma, melanocytic lesions, shwannomas, dural metastases), but also non-tumoral lesions (aneurysms; dermoid and epidermoid cyst) Conclusion: Meningiomas account for 14-20% of intracranial tumors. The diagnosis is relatively easy when the tumor has characteristic radiological fi ndings. However, the radiologist must be aware of the less frequent imaging features in order to suggest the diagnosis in cases that meningiomas are atypical. Most meningiomas are benign (90%), but there are also atypical (5-7%) and malignant (1-3%) variants that

have specifi c histopathological characteristics. These meningiomas show unusual imaging fi ndings more frequently. The distinction between atypical and typical meningiomas is clinically relevant, because benign tumors recur in about 7-20% of cases, where as atypical variants recur in 29-41%. Furthermore, the treatment is different in both cases.

Epileptogenic structural disorders in pediatric patients: MR imaging characteristics A. Mallouhi, T. Gotwald, E. Haberlandt, G. Feuchtner, E. Trinka, S. Felber, D. Zur Nedden; Innsbruck/AT (Ammar.Mallouhi@uibk.ac.at)

Learning Objectives: 1. To provide an MR imaging overview of epileptogenic structural disorders in pediatric patients. 2. To familiarize with the key MR fi ndings necessary to assist in rendering a diagnosis. Background: Epilepsy is a chronic condition that results from abnormal excessive activity of a population of cerebral neurons. Several brain structural disorders have been implicated in epilepsy in pediatric patients. Imaging Findings: In this exhibit, we illustrate a spectrum of brain structural disorders encountered in MR imaging of pediatric patients with intractable epilepsy and their implications on treatment planning including cortical development abnormalities (focal cortical dysplasia, schizencephaly, heterotopia, polymicrogyria), hippocampal sclerosis, vascular malformations, post-traumatic lesions, infections, tumors, neurocutaneous disorders (neurofi bromatosis I, tuberous sclerosis), and mitochondrial disorders. Conclusion: Magnetic resonance imaging is the radiological method of choice for the detection and characterization of parenchymal abnormalities that provoke epileptic seizures. Conventional and high-resolution MR signal characteristics assist in determining a specifi c diagnosis.

Diffusion tensor imaging in the early stages of stroke can predict dysphage outcome X. Wei, J. Dai, H. Shen, J. Ma, L. Ai, S. Li, X. Zhang; Beijing/CN (weixinhua2007@163.com)

Purpose: To determine whether the degree of impairment of diffusion tensor imaging in the early stages of a stroke can predict the dysphage outcome. Methods and Materials: Twenty-fi ve unilateral hemispheric stroke patients were enrolled to this study. Diffusion anisotropy was measured by determining fractional anisotropy (FA) in the ROIs (region of interests) placed in the bilateral posterior limb of internal capsule (IC) during the early stages of stoke (average 7.3 days after stroke onset) and compared with dysphage outcome 3 months after stroke onset. Results: Seventeen patients with complete recovery were assigned to group one and 8 patients with persistent dysphage were assigned to group two. No signifi cant difference in FA between the bilateral posterior limb of IC in group one (p> 0.05). However, FA of the bilateral posterior limb of IC in effect side was lower than that of the intact side in group two (p < 0.05).

The degree of impairment in diffusion anisotropy during the early stages of stroke appears to have the potential to predict dysphage outcome.

Flow-pattern on superselective middle cerebral artery (MCA) angiography can predict tissue recovery after local recanalization treatment for hyperacute MCA occlusion Y. Hori, H. Kiyosue, H. Mori, J. Kashiwagi, H. Nagatomi, Y. Sagara, S. Tanoue, M. Okahara, T. Asano, R. Shimada; Oita/JP (horiyuzo@med.oita-u.ac.jp) Purpose: In hyperacute middle cerebral artery (MCA) occlusion, viability of brain tissue depends on the residual blood fl ow which could affect the outcome after local recanalization treatment (LRT). The purpose of this study is to investigate whether superselective MCA angiography obtained prior to LRT could predict the recovery of ischemic brain tissue. Methods and Materials: Thirty-six patients having hyperacute MCA occlusion (32 patients of M1 occlusion, 4 patients of M2 occlusion) without signs of cerebral infarction on early CT underwent LRT. Pretreatment superselective MCA angiography via the microcatheter placed just distal to the occlusion site was executed to evaluate the fl ow-pattern in 60 (31 anterior trunks, 29 posterior trunks) of 68 trunks. The fl ow-patterns were classifi ed into three types: antegrade (n=28), retrograde (n=26), or stasis (n=6). The relationship between the degree of recanalization and follow-up CT fi ndings in each fl ow-pattern was investigated. Results: Cortical infarction occurred in 28 of 60 trunk territories. In antegrade type, 3 (21%), 8 (73%), and 3 (100%) territories had cortical infarctions in complete, partial, and failed recanalization, respectively. In retrograde type, 1 (14%), 2 (40%), and 5 (36%) territories had cortical infarctions in complete, partial, and failed, respectively. In stasis type, 6 (100%) territories had cortical infarctions regardless of degree of recanalization. The degree of recanalization is signifi cantly correlated with follow-up CT fi ndings in only antegrade type. Conclusion: Flow-pattern on superselective MCA angiography has signifi cant relationship with brain tissue recovery. Cases with antegrade fl ow-pattern would be a good indication for LRT. 

Intraventricular brain tumors: A pictorial review J. Sanchez 1 , P. Puyalto 2 , C. Majos 1 , C. Aguilera 1 , L. Aja 1 , J. Acebes 1 ;

Learning Objectives: To describe the characteristic radiological features of intraventricular tumours that may allow their appropriate recognition and precise diagnosis. Background: Intraventricular neoplasms are uncommon; they represent only the 10% of all intracranial tumours. Due to their deep location within the brain, they usually have diffi cult surgical access and consequently more potential risks of complications and consequently imaging assessment previous to surgery is essential to evaluate the extension and location of these tumours. Imaging Findings: Imaging features of 173 patients with intraventricular tumours were retrospectively reviewed. They showed a wide spectrum of radiological appearances that were non-specifi c, in many cases, making its differentiation diffi cult. The location of the mass within the ventricular system and the patient's age provided the most useful information, but other radiological features (calcifi cations, cysts, bleeding or enhancement) were helpful too. MR is the best technique to assess location and extent of the disease but in certain cases CT provides complementary evaluation of aspects such as calcifi cations or bleeding. Conclusion: Based on patient's age, location of the tumour within the ventricles and specifi c radiological features on MR, an accurate diagnosis can be made.

Regional gray and white matter volume abnormality in obsessive- (OCD) . No studies were found that showed white matter (WM) abnormality. The purpose of this study was to assess both GM and WM volume abnormality in OCD patients using voxel-based morphometry (VBM). In addition, it provides a very important functional information that can be very useful in the differential diagnosis of several lesions including cerebral abscess or herpetic encephalitis. Imaging Findings: We have reviewed 27 studies performed at our department for evaluation of patients with suspected CNS infection. 21 patients for brain abscess, including Toxoplasma in AIDS patients, and pyogenic abscess. CTP showed ring enhancing lesions with vasogenic oedema in contrast enhanced CT with reduced cerebral blood volume (CBV) in the lesion in CTP. Tumors have increased CBV. In addition, CTP permits a better depiction of residual enhancement of partially calcifi ed lesions. Three patients of Herpes Simplex virus encephalitis showed regional hyperperfusion in the acute phase and hypoperfusion in the chronic phase. Also, other 3 cases of other CNS infections including fungal infections are described in our series. Conclusion: CT perfusion could be included as a complimentary technique in brain CT studies because it provides useful funcional information, especially useful when MRI is not available or for noncollaborative patients.

Metabolic changes observed with proton MR spectroscopy in normal human brain tissue during radiation therapy L. Zarudzki, B. Bobek-Billewicz, W. Senczenko, A. Idasiak; Gliwice/PL (lzarudzki@op.pl) Purpose: To observe the time course of changes in the proton magnetic resonance spectroscopy (1H-MRS) values during radiation therapy in normal human brain tissue. Methods and Materials: We followed 18 patients receiving an external radiation therapy for primary gliomas for 2 months. All of the patients underwent brain surgery prior to the radiotherapy. The patients received 54 or 60 Gy in tumour bed and 20-50 Gy in the contralateral normal brain hemisphere. Each patient underwent single voxel spectroscopy (SVS, TE=135; TE=30) before and just after the completion of the radiation therapy. The voxels of interest were chosen in the contralateral normal brain hemisphere to meet an area between 30% and 50% isodose lines in the radiotherapy plan. The metabolite concentrations: N-acetylaspartate (NAA), choline compounds (Cho), creatine (Cr), lactate (Lac), lipids (Lip), inositol (Ins), glutamate and glutamine (Glu+Gln), their ratios and normalized concentrations were calculated. The spectra were verifi ed with LCModel.

Results: There was a statiscally signifi cant decrease of total choline and inositol concentrations, their normalized concentrations and Cho/Cr, Ins/Cr ratios. The changes in the other metabolite concentrations were not signifi cant. Conclusion: It is possible to detect and to evaluate in vivo early metabolic effects of radiation therapy in the normal human brain tissue with the proton magnetic resonance spectroscopy. The cause of the observed changes is unclear and might be due to the alterations of membrane composition related to the radiotherapy.

Cerebral organization of language processing for different input modalities in Chinese: An fMRI study Y. Yang, K. Li, Y. Xu, H. Shu; Beijing/ CN (yyh_wj@sohu.com) Purpose: The processing of Chinese may be different from alphabetic languages such as English not only in the behavior but also in the neural mechanism. In this study, functional magnetic resonance imaging (fMRI) was used to investigate the neural mechanism of semantic information processing. Methods and Materials: Twelve normal subjects were scanned with a 1.5 T MR scanner. According to different modalities, there were auditory semantic judgment (ASJ), picture semantic judgment (PSJ), and word semantic judgment (WSJ) involved in our experiment. When subjects heard a word or saw a white-black drawing picture/word, they must decide whether it is dangerous or not and press the corresponding button. A block design was employed and the baseline task was passively listening to a pure tone or viewing a cross. The fMRI data were analyzed using the SPM2. Results: Bilateral superior temporal gyrus, left inferior and middle frontal gyrus were activated during the auditory task. Bilateral occipital regions, left inferior and middle frontal gyrus, and left parietal regions were associated with the processing of all the visual stimuli. However, the word task produced no more activation than the picture task in the prefrontal area or the temporoparietal region, which were reported in similar studies on English.

The inferior and middle frontal gyrus may be related with semantic processing of Chinese word regardless of the input modalities. It is showed that Chinese words are to some extent more similar to pictures and the neural mechanism of Chinese words processing is similar to that of pictures.

Whole brain real-time fMRI of language and hand motor areas with prospective acquisition correction for movements (PACE) C. Zimmermann, S. Langner, J. Kuehn, M. Domin, N. Hosten; Greifswald/DE (christian.zimmermann.hgw@web.de) Purpose: Mapping of language and hand motor brain areas has become an important clinical application of fMRI in neurology and neurosurgery. We assessed the feasibility of real-time fMRI with prospective acquisition correction for movements (PACE) in routine clinical examinations. Methods and Materials: Twenty normal subjects and 11 patients with temporal lobe epilepsy or intracerebral tumors were examined at 1.5 T (Siemens Symphony). An 8-channel head coil was used for acquisition of anatomical T1 GRE, T2 TSE and an EPI BOLD sequence. A semantic decision and letter-matching task alternated every 24 s. The motor paradigm was an alternating fi nger-tapping task of ten 30-s periods of activation. A z-score of 4 was chosen as cut-off. Results: Table time was under 20 min for language and 13 min for motor fMRI. B D E F A G

In 19/20 subjects language lateralization and in 20/20 the hand motor area were identifi ed. Imaging was diagnostic in all patients. In all 17 right-handed subjects, speech areas were mainly located in the left hemisphere. Two left-handed subjects showed different activation: one in the left and the other mainly in the right hemisphere. For the speech paradigm, 10 of the right-handed subjects showed right hemispheric activation of the cerebellum. One of the left-handed subjects had left and the other right hemispheric cerebellar activation. Conclusion: Real-time fMRI is a feasible technique for noninvasive mapping of language and hand motor areas in clinical routine, providing reliable feedback of activation after 60 s of paradigm runtime.

Susceptibility weighted ( Learning Objectives: To demonstrate magnetic susceptibility as a means of contrast in MRI. To describe data-acquisition and post-processing of susceptibilityweighted (phase) images (SWI). To recognize artifacts. To demonstrate the technique in clinical cases and to compare it with standard MR imaging methods. Background: Magnetic susceptibility is a physical property of tissue that infl uences the MR-signal via the local precession frequency. Different blood-oxygenation levels, cerebral iron concentrations and many pathologies produce contrast in both magnitude and phase of gradient echo images. Procedure Details: High resolution 3D fl ow compensated gradient-echo data are acquired at long TE. Matrix=512x256x36, TE/TR/alpha=40/60/25 at 1.5 T, TE/TR/ alpha=30/40/20 at 3 T. Phase images are unwrapped with either a homodyne fi lter or a region-growing algorithm. The latter produces better results in magnetically inhomogeneous areas. The susceptibility-weighted MR phase images show a unique contrast independent of T1 and can be directly assessed and compared to the corresponding T1/T2*-weighted magnitude images from the same scan. Multiplying masks computed from the phase with the magnitude produces susceptibility-weighted images, which allow assessment of vascular architecture and function (if acquired during hypercapnia and normoxia). SWI of Sturge-Weber syndrome, tuberous sclerosis, tumors, arteriovenous malformations etc. provides additional information that is not accessible by conventional imaging. Conclusion: Susceptibility-weighted MR (phase) imaging of the brain provides valuable information at high spatial resolution. It facilitates detection of small lesions which may be missed by conventional methods. At 3 T acquisition time is reduced to 4-5 minutes due to shorter TE and the option to use parallel imaging because of increased SNR.

The effi cacy of fusion three-dimensional-computed tomography (3D-CT) for following treated cerebral aneurysms by coil embolization M. Ishifuro, J. Horiguchi, Y. Kiura, K. Ito, T. Furukawa; Hiroshima/JP (ishifuro@hiroshima-u.ac.jp) Purpose: Owing to metallic artifacts, vessels and coils cannot be observed in patients after coil embolization (CE) by CTA. Thus, the purpose of this study was to examine whether fusion CT could overcome this problem. Methods and Materials: Ten patients underwent CE for cerebral aneurysm. CTA was performed before CE, and plain CT was performed after CE. Two sets of 3D images were constructed with 3D image analyses software (Virtual Place, AZE). Postoperative 3D coil images were fused with preoperative CTA images in order to reduce artifacts due to the coils. We compared the coil locations on these fusion CT images to those on postoperative DSA. Results: All 3D fusion images with CTA and coils were successfully constructed. Fusion CT could reveal postoperative fi ndings as accurately as DSA. Also, we could evaluate the cases whose results were classifi ed as neck remnants. Conclusion: Fusion CT furnished as accurate information for postoperative fi ndings as did DSA; hence, it may be useful in predicting whether coil compaction will occur.

Brain MRI of Guadeloupean patients suffering from progressive supranuclear palsy L. Giré 1 , A. Lannuzel 2 , D. Ben Salem 1 , P. Giré 1 , F. Ricolfi 1 ; 1 Dijon/FR, 2 Pointe-à-Pitre/FR (laurentpaulinegire@yahoo.fr)

Purpose: To describe brain MRI features of Guadeloupean progressive supranuclear palsy (Gd-PSP). In Guadeloupe, a french territory in West-indies, a cluster of progressive supranuclear palsy-like taupathy has been reported with an unusual high frequency, maybe linked to the consumption of specifi c fruit and derived tea from the annonaceae family. Methods and Materials: Thirty-four clinical Gd-PSP underwent prospective brain MRI studies, from December 2004 to September 2005. MRI evaluation was performed with a 1.5 T MR imaging (Philips intera), in the University Hospital Radiology Department of Pointe-à-Pitre, Guadeloupe (France). The standard protocol included 6 sequences: sagittal T1-weighted Turbo Spin-Echo, axial T2w TSE (3 mm slices), Coronal T2w TSE (3 mm slices), Axial T2 * FFE, axial T2w FLAIR, axial protondensity. On each MRI, brain atrophy (cortical, subcortical, posterior fossa) and signals abnormalities (hypo or hyper signals on T2w images) of midbrain, pons and basal ganglia were respectively measured and evaluated. Each MRI was reviewed independently by two neuroradiologists. Results: Eight of 34 Gd-PSP MRI were not reviewable (motion artefacts). On the 26 exploitable cases, interobserver concordance of atrophy was good (p < 0.001). 80% had midbrain atrophy of which 32% presented a "hummingbird sign" on midsagittal T1w images. 75% had frontal atrophy. 19.2% presented an "état criblé" in the basal ganglia, without "hummingbird sign". Two patients presented an unusual tegmental T2 hyperintensity. Conclusion: Gd-PSP present a comparable or higher rate of midbrain atrophy than other PSP described in literature. The "état criblé" presented by some of these atypical Parkinson's syndromes may have an associated vascular origin.

Correlation of auditory simple reaction time ( Studies propose that inter-individual differences in reaction time are due to physiological white matter differences, especially myelination; however, a proof is still missing. Therefore, we aimed to fi nd a correlation between inter-individual reaction time differences and fractional anisotropy (FA), which is known to show white matter differences. Methods and Materials: Twenty-two healthy students (right-handed, age: 23.1 ± 0.7 years) underwent an auditory simple reaction task based on the classic Poffenberger paradigm. 8 blocks of 36 trials were conducted, preceded by 2 blocks of 36 practice trials with an inter-block pause of 30-60 s. Whole head DTI was performed using TRSE-EPI sequence with an isotropic spatial resolution of 2 mm 3 . Voxel-based regression analysis was conducted between fractional anisotropy and inter-individual aSRT results. Results: Signifi cant negative correlation [pFWE (family wise error probability) = 0.032] was found in the right-central cerebellum. Potent signifi cance was detected with right-sided stimulus presentation and response. No signifi cant correlation was observed, neither for left handed response nor left ear stimuli. Discussion: Our results imply an association between fractional anisotropy in the right-central cerebellum and aSRT measures. Presumably, the reason for this correlation is an infl uence of handedness on FA and aSRT. Since FA does not characterize specifi c tissue properties but represents an index of WM integrity, the micro-structural/physiological basis of these fi ndings requires further research from which important insights into the mechanisms of behavioral performance may be obtained.

Axonal damage and infl ammation relationship by 1H-MRSI and T2weighted MRI in early relapsing remitting multiple sclerosis: The effects of subcutaneously interferon beta-1a treatment M.C. Purpose: To examine the relationship between axonal damage in NAWM in brainstem and infl ammatory activity in patients with early relapsing remitting multiple sclerosis (RRMS) and to assess the effects of interferon beta-1a (IFNB1a) on metabolic brainstem changes and parameters of infl ammation. Methods and Materials: Sixteen RRMS patients treated with IFNB1a, twenty RRMS patients untreated and ten healthy subjects were prospectively studied for two years. Relapse rate (RR) was calculated annually. T2-weighted MR and 1H-MRSI were acquired at recruitment and at two years follow-up. T2-weighted lesion volume (T2LV) was measured. NAA, Cr and Cho resonances ratios were calculated for the sum of the volume elements that represented the brainstem. Disability was rated with EDSS and MSFC.

Results: Basal NAA/Cho ratio at brainstem was decreased in RRMS compared with controls. After follow-up, there was a decrease in NAA/Cho (-9%) and NAA/Cr (-15%) while T2LV increased (18%) in RRMS, without changes in controls. Patients with more than one relapse showed lower NAA/Cho at follow-up. NAA/Cho correlated with EDSS. At follow-up, an inverse correlation was found between NAA/Cho and T2LV (p=0.008). IFNB1a was effective in reducing disease activity (annual RR and T2LV) but ineffective in delaying axonal damage (all RRMS suffered metabolic decrements). Conclusion: Axonal damage begins and progresses from early stages of MS and has been related with clinical and radiological evidence of infl ammation. However, the stabilising effect of IFNB1a on infl ammatory activity appears not suffi cient in reducing neuroaxonal damage in a short-term study. Longer periods of observations are needed to confi rm these preliminary fi ndings. In the analysis of 1 H MRSI one voxel in each hemisphere including the inferior colliculus was selected for quantitative analysis. jMRUI program was used to analyze multivoxel. Relations among peak areas of NAA, Cr and Cho in the inferior colliculus were compared among groups in each region. SPSS 12.0 program was used for statistical analysis.

Results: Colliculus showed signifi cant reduction of the ratio NAA/Cr in both hemispheres in schizophrenic patients compared with control subjects. In the comparation among groups hallucinators showed the smallest value of NAA/Cr followed by not hallucinators and controls. The comparison of the two types of schizophrenic patients did not show signifi cant differences in this localtion.

The biochemistry of inferior colliculus, involved with auditory pathway, could be altered in schizophrenic patient with auditory hallucinations. In this study, MRS has shown metabolic differences between control and schizophrenic patients in these areas, without any signifi cant differences among hallucinators and no hallucinators.

The functional connectivity study of acupuncture analgesia effect in human brain H. Chen, J. Dai, J. Tian, W. Qin, P. Chen, Z. Zhen, L. Ai, L. Yang; Beijing/ CN (hyc221@yahoo.com.cn) Purpose: Functional connectivity provides the functionally related and connected information among interdependence of brain regions. We used functional connectivity MRI analysis to detect if there is a functional network associated with the effect of endogenous analgesia. Methods and Materials: Fourteen right-handed Chinese healthy college students [7 male and 7 female in the age of 22-26 years] were performed two functional MRI examinations using 3 T Siemens Trio scanner. One was a resting state lasting for 15 minutes and the other was performed during a 3 minute acupuncture needle manipulation on the ST36 followed by 15 minutes steady states scan. These two runs had an interval of 30 minutes. All data were preprocessed using SPM2. The left side amygdala area was chosen as the ROI. The seed timecourse was crosscorrelated with all other low-pass fi ltered voxels to form functional connectivity maps for each subject. Finally to compare the difference of resting state connectivity and the resting state connectivity after acupuncture, a paired Student t-test was implemented across subjects.

The compelling similarity existed in the network of resting state before and after acupuncture. The main difference between the two networks was found in the limbic system, brainstem and cerebellum. Conclusion: We conclude that the default endogenous analgesia functional network exists in human brain at a low level, and it could be increased to a higher level by acupuncture modulation.

The association between the cavernous carotid artery calcifi cation (CCAC) on CT and fractional anisotropy (FA) of the brain white matter using 3 T MRI A. Seko 1 , K. Maeda 1 , Y. Nakano 1 , S. Kitahara 2 , K. Learning Objectives: The aim of this exhibit is to illustrate a wide spectrum of usual and unusual manifestations of primary central nervous system lymphoma (PCNSL) and to highlight the role of CT and different MR sequences in the accurate diagnosis of this entity. Background: PCNSL is an uncommon aggressive form of extranodal non-Hodgkin lymphoma that originates in the CNS without evidence of lymphoma in any other localization at the moment of diagnosis. It represents 0.5-2.0% of primary malignant lesions of the CNS and affects brain, eye, meninges, cranial, spinal, and peripheral nerves. Incidence during the last three decades has increased both in immunocom-

promised and immunocompetent hosts between 45-60 years old and has become the fi rst brain tumour in patients with the acquired immunodefi ciency syndrome. Imaging Findings: CT and MR show, mostly, an isolated mass involving deep grey matter, periventricuar regions and corpus callosum with or without surrounding edema. After contrast injection, the tumour may enhance diffusely and densely or in its periphery (ring enhancement) if central necrosis is present. If perivascular spaces or meninges enhance as well, the diagnosis of PCNSL should be strongly considerated. Calcifi cations or bleeding are rarely seen. Surrounding edema and multifocal lesions are more frequently seen in immunocompromised patients. Conclusion: Due to new therapeutical strategies, the outcome for patients with PCNSL is rapidly improving in recent years; although the fi nal diagnosis relies on stereotactic biopsy demonstrating lymphomatous cells, the radiologist plays an important role in the noninvasive diagnosis of PCNSL thanks to the imaging fi ndings provided by CT and the combination of different MR sequences.

Prospective Results: Group 1 included 38 males, 21-92 y, and 12 females, 41-80 y, with clinical onset 2-8 h before CCT; mNIHSS was 0-28. Group 2 also included 38 males, 27-81 y, and 12 females, 25-78 y. Onset of symptoms was 3-8 h before CCT, mNIHSS was 0-28. Sensitivity in group 1 was 58.3%. Detection of small ischemias in the basal ganglia was particularly poor. Multimodality CCT in group 2 showed true positive results in 32 of 50 cases, and false negative in 6 of 50 cases, with a sensitivity of 84.2%. CT angiography was helpful in selected cases for detection of intracranial stenoses/occlusions, but limited by motion artifacts. Nine occlusions/stenoses of the intracranial arteries were diagnosed. Conclusion: Multimodality CCT is superior to unenhanced early CCT for detection of acute cerebral ischemia, and should serve as a basic diagnostic tool for establishing local stroke units.

Imaging of the central skull base: Anatomic study I. Pérez 1 , M. Aperribay 1 , G. Benito 1 , I. Terreros 2 , A. Dolado 2 , J. Mendiola 2 ; 1 Mondragón/ES, 2 Baracaldo/ES (irunepe@hotmail.com) Learning Objectives: To review the anatomy of the skull base including the skullbase foramina and their content, the osseus anatomy of the pterygopalatine fossa, and the sutures and boundaries of the skull base. After reading this exhibit, the reader will be able to understand the complex anatomy of the skull base, to accurately delineate phatologic processes, and to understand the spread pathways of different lesions involving this complex region. Background: The radiologist requires a thorough knowledge of the normal anatomy and the pathologic spectrum of the skull base. Imaging plays a central role in the management of skull-base disease, because this region is, in general, inaccessible to clinical evaluation. CT is ideal for outlining the bone architecture, whereas MR imaging provides soft tissue details. The pterygopalatine fossa represents a major pathway of spread of malignancy and infection from the head and neck into the skull base. Imaging Findings: A pictorial review of the skull base with foramina and their content (foramen ovale, rotundum, spinosum, lacerum, yugular foramen, and carotid canal), the pterygopalatine fossa and its boundaries, and the sutures of the skull base (occipitomastoid, sphenosquamous, petrosphenoid fi ssure, petrooccipital fi ssure, pterygomaxillary fi ssure) is provided. Conclusion: Familiarity with the complex anatomy of the skull base is a prerequisite for the correct diagnosis and accurate delineation of skull-base lesions. CT and MR imaging are complementary modalities and are often used together to demonstrate the full disease extent. 

The The aim of this study was to determine whether the anatomy of the CoW infl uenced the incidence, severity and location of these lesions. Methods and Materials: Thirty term neonates with HIE underwent MRI with standard structural sequences and high-resolution 3D time-of-fl ight MR angiography. The CoW was examined for completeness and anatomical variations. The presence and distribution of WM and BGT lesions were noted and the lesions were graded according to predefi ned criteria.

The CoW was complete in 50% of infants. BGT or WM lesions occurred in 21 infants, with severe changes in 7, moderate in 9 and mild in 5 infants. In those with severe changes, 6 had incomplete CoW and 5 of these had an absent anterior communicating artery (A-Com). The only 2 infants in the study with absence of both anterior and posterior communicating arteries had severe changes. The anatomy of CoW did not infl uence the location of the lesions.

The presence of specifi c anatomic variations in CoW may infl uence the severity of ischaemic WM or BGT lesions in infants with HIE. Infants with incomplete CoW may have limited ability to adequately perfuse the brain following a hypoxic-ischemic insult and therefore present with more severe lesions.

Imaging spectrum of cerebral amyloid angiopathy J. Kim, K. Ahn, S. Jung, B.-S. Kim; Seoul/KR (jeeyoungkim@catholic.ac.kr) Learning Objectives: To demonstrate the various CT and MR imaging fi ndings and pathogenesis of cerebral amyloid angiopathy. Background: Recently, cerebral amyloid angiopathy (CAA) has attracted attention for its close relationship to cerebral hemorrhage (ICH), ischemic lesions, Alzeheimer's disease (AD), and other types of dementia in the elderly. Most common presentation of CAA is massive isolated or multi-compartmental intracranial hemorrhage, but it is also found in association with subacute or chronic edematous lesion of the white matter with or without CAA-related hemorrhage. Procedure Details: The CT and MR images of histologically proven or clinically diagnosed CAA were described with regard to type (lobar or petechial hemorrhage), location, and relapse of cerebral hemorrhage and presence or absence of white matter change (leukoencephalopathy) with pathogenesis of these lesions.

The usual presentation of cerebral amyloid angiopathy is spontaneous lobar hemorrhage in the elderly patients, especially in those patients more than 70 years of age. However, cerebral amyloid angiopathy presents various imaging fi ndings such as cortical petechial hemorrhage and subcortical or deep white matter change with or without cerebral hemorrhage.

Whole-brain three-dimensional CT perfusion K. Yuba, K. Ono, K. Suzuki, Y. Yoshimoto, K. Wada, D. Yamana; Meguro-ku,Tokyo/JP (mishuku-CT@mishuku.gr.jp) Purpose: CT perfusion functional evaluation is a promising method for evaluating blood fl ow in patients with cerebral ischemia. The conventional method suffers from the limitation that the area that can be evaluated is restricted. The present study was conducted to assess a new display method for evaluating the distribution of blood fl ow in the brain by combining whole-brain imaging and multiplanar reconstruction.

To cover the entire brain, scanning was performed several times with the scan slice thickness reduced from 8 mm to 2 mm, and the number of scan slices increased from 4 to 16. Saline solution was used in combination to reduce the volume of contrast medium, and a quantum denoising fi lter was used to minimize the exposure dose. For image processing, several data series were bundled into a single series. This technique permits multiplanar display of wholebrain blood fl ow, which is not possible with the conventional method. Results: Evaluation of this new display method for CT perfusion studies showed that three-dimensional display permits the cerebral blood fl ow distribution to be observed from any desired direction. This method makes it easier to visualize ischemic areas and is expected to prove useful as a new CT perfusion display method. Conclusion: Three-dimensional CT perfusion permits blood fl ow in the entire brain to be evaluated stereoscopically. This method fully exploits the advantages of a larger number of CT detector rows and is expected to gain widespread acceptance as a useful new CT perfusion imaging technique and display method.

Evaluation of cerebral metabolite patterns with proton MR spectroscopy in chronic renal failure patients: Correlation with duration of hemodialysis S.E. Kim, H. Baik, H. Yu, Y. Lee, G. Kim; Seoul/KR (tlwodc@hanmail.net) Purpose: To evaluate cerebral metabolite patterns with proton MR spectroscopy (MRS) in chronic renal failure (CRF) undergoing hemodialysis (HD) and to clarify if these fi ndings correlate with duration of HD. Methods and Materials: Subjects comprised 15 CRF patients undergoing HD and 15 healthy volunteers. Short TE (=32 ms) single voxel proton MRS and laboratory data were acquired in CRF patients before HD and one day after HD. Spectra were obtained from two voxels of interest positioned in the gray and white matter of parietal lobe. Changes in N-acetylaspartate (NAA), choline (Cho), myoinositol (Myo), glutamine/glutamate complex (Glx) and creatine (Cr) were analyzed and the results presented as ratios, with Cr as the reference. Metabolic ratios and laboratory data before and after HD were compared. Correlations between each metabolite ratio and laboratory data, and between each metabolic ratio and duration of HD were evaluated. Results: In CRF patients, the Cho/Cr ratio and Myo/Cr ratio were signifi cantly elevated in gray matter and the Myo/Cr ratio was signifi cantly elevated in white matter compared with controls (p <.05). After HD, the Cho/Cr ratio was significantly reduced in white matter of CRF patients (p <.05). There were no signifi cant correlation between each metabolic ratio and laboratory data, and between each metabolite ratio and duration of HD.

The signifi cant elevation of the Cho/Cr ratio in gray matter and the B D E F A G Myo/Cr ratio in gray and white matter was found in CRF patients compared with controls. There was no signifi cant correlation between cerebral metabolite ratios and overall time of HD.

Imaging Learning Objectives: 1. To describe and depict CNS infections within the different compartments of the brain. 2. To illustrate characteristic imaging fi ndings attributable to specifi c pathogens. 3. To demonstrate infectious etiologies specifi c to immunocomprised and HIV patients. Background: Localizing a lesion within the intracranial compartment is the fi rst critical step in constructing a differential diagnosis. Furthermore, certain types of infections have certain propensities for different anatomical regions within the brain and can possess certain imaging characteristics. Of course, the imaging fi ndings must be placed in the context of the clinical setting particularly in immunocomprised and HIV patients. Imaging Findings: We present a pictorial review of infections within different compartments of the brain. Pathology proven infectious cases will be presented in both immunocompetent and immunocompromised patients with discussion of the characteristic fi ndings of each pathogen and differential diagnosis.

The radiologist plays a crucial role in identifying and narrowing the differential diagnosis of CNS infections. A thorough understanding of the intracranial compartment anatomy and characteristic imaging fi ndings of specifi c pathogens as well incorporating the clinical information is essential to arrive at the correct diagnosis. histologic diagnosis of meningioma were studied in our center, 23 (9.3%) were atypical and 6 (2.4%) malignant. We reviewed the CT and MRI fi ndings of these 29 patients with pathologically confi rmed atypical and malignant meningioma diagnosed. We illustrate different appearences of atypical and malignant meningioma. Pitfalls, diagnostic diffi culties and differential diagnoses are emphasized. Conclusion: After interacting with this exhibit the radiologist will improve his or her knowledge of atypical and malignant meningioma, including histopathology and radiologic features.

11C-sodium butyrate-PET in neurooncology N.A. Kostenikov, L.A. Tyutin, N.P. Fadeev; St. Petersburg/RU (crirr@peterlink.ru) Purpose: The aim of the study was to determine the potential in diagnosis of pathological volume brain formations (PVBF) by PET with 11C-Sodium Butyrate (11C-SB). Methods and Materials: PET was performed in 143 patients (74 men and 69 women, at the age of 18-79 y.o). to identify tumors or to exclude an advance growth of tumors. According to the results of histological data, malignant tumors were revealed in 77/143 patients, benign tumors in 28, arterial venous malformations (AVM) in 12, stroke diseases (SD) in 4, and cysts in 22. 2D-PET scans of the brain with attenuation correction («Ecat Exact 47 HR+», Siemens) were performed in a dynamic mode immediately after intravenous administration of 550-650 MBq 11C-SB. We used tumor/normal tissue ratio (T/NT) as an index for semiquantitative data analysis, as well as analysis of activity/time curves. Results: Results of the studies showed PET with 11C-SB proved to be a highly sensitive (94.8%) technique in revealing brain tumors and it allowed to visualize clearly malignant and hypervascular benign tumors and to differentiate them from non-tumor masses of the brain. Dynamic 11C-SB-PET allows to assess the grade of vascularity, the level of metabolism, the rate of uptake and utilization of fatty acids (FA), and to estimate indirectly the state of tumors oxygenation.

The performed studies showed that dynamic PET with 11C-SB allows to visualize precisely malignant brain tumors and estimate their morphological state; the latter is of prognostic value in order to plan conservative therapy for brain tumors.

Susceptibility-weighted imaging ( Purpose: To assess the fi ndings of susceptibility-weighted imaging (SWI) with 3-Tesla in acute ischemic stroke. Methods and Materials: Twenty patients underwent CT and MR imaging with SWI, diffusion-weighted imaging (DWI), and 3D-TOF MRA within the fi rst 5 days after the onset of acute ischemic stroke. The SWI sequence is a high-resolution threedimensional (3D) imaging technique with 3-Tesla. The susceptibility changes by the intraarterial clots or emboli, hemorrhage, and the enhancement of the regional vein in the abnormal perfusion area of the brain were assessed on SWI. Results: The intraarterial susceptibility changes by the fresh clots or emboli were visible on SWI in 8 cases. SWI showed distal clots or emboli that were invisible on both of MRA and fl uid attenuated inversion recovery (FLAIR) images in 6 cases. The hemorrhagic infarction occurred in 5 cases. The hemorrhage was shown on SWI earlier than on CT image in each case. The enhancement of the regional vein in the abnormal perfusion area of the brain was shown in 6 cases on SWI. All of them were within 2 days after the onset of acute ischemic stroke. Five of the 6 cases were embolic infarction cases of the MCA territory. Conclusion: SWI is an effective means that can provide additional information about the fresh intraarterial clots, hemorrhage, and the perfusion anomaly in the brain in acute ischemic stroke. 

BOLD fMRI response in the motor cortex is strongly linked with vasoreactivity in patients with carotid artery disease C. Ojango, S. Goode, D.P. Auer; Nottingham/UK (msxco@nottingham.ac.uk) Purpose: Blood oxygenated level-dependent (BOLD) functional MRI (fMRI) has become a widely used technique to investigate brain activation. The method is based on haemdynamic changes and any alteration in neurovascular coupling, baseline blood fl ow or volume is likely to affect results. It has been shown that stroke and carotid artery disease reduce cerebrovascular reactivity (CVR) and this factor infl uences the response to motor tasks. We explored further the interrelation between the motor task induced signal change and the CVR in patients with carotid artery disease. Methods and Materials: Six patients (age 55-80) with internal carotid artery stenosis (> 60%) were investigated with motor task and co 2 stimulation. The data analysis was performed with FSL software. The mean percentage of signal intensity change during the motor task and co 2 challenge was calculated separately for both motor cortices.

Results: There was a signifi cant correlation between the BOLD responses to the motor task and co 2 stimulation (Pearson test 0.69, p=0.01). We did not fi nd differences in motor BOLD responses between the side of the maximum stenosis and the contralateral hemisphere. Conclusion: These results confi rm the effect of vasoreactivity on BOLD response in patients with carotid artery disease and show that neurovascular coupling is linearly and strongly correlated with CVR. In the small sample, no difference emerged between hemispheres suggesting that the degree of stenosis may be less relevant for the BOLD response than CVR. The observed relationship is important for designing clinical fMRI studies to avoid confounding effects from altered vasoreactivity.

The value of perfusion MR to differentiate between low and high grade brain gliomas R. Rodríguez-Romero, J. Vivancos-García, P. Piñero Gonzalez de la Peña, C. Monreal-Rodríguez; Sevilla/ES (raroro@terra.es)

Purpose: To determine the value of Magnetic Resonance perfusion imaging to differentiate between low and high grade brain glioma. Methods and Materials: Forty-seven patients with brain glioma were studied with conventional MRI followed by dynamic susceptibility-weighted gadoliniumenhanced perfusion-MRI. 14 were Low Grade gliomas (I-II WHO) and 34 were High Grade gliomas (III-IV WHO). Studies were performed with a 1.5T Philips MR system. Region of Interest was measured in the 5-6 most vascularized areas of the tumor. The maximum Cerebral Blood Volume (CBV) value was recorded for each area and divided by CBV of the contralateral periatrial white matter to obtain the relative CBV (CBVr Purpose: Endovascular stenting is evolving as the primary treatment option for cervical arterial dissections in symptomatic patients refractory to medical management. The tractability of balloon-or self-expandable stents into the tortuous intracranial vasculature is often diffi cult. Six patients at our institution have been treated using the fl exible intracranial Neuroform stent in tortuous dissected segments of the distal carotid and vertebrao-basilar arteries. We studied this population to evaluate this treatment approach. Methods and Materials: Six patients with distal internal carotid or vertebralbasilar dissections were treated using intracranial Neuroform stent. A total of 10 stents were utilized in 6 procedures. Dissecting aneurysms were treated via stent assisted coil embolization. Patients were followed with imaging and clinical assessment for a mean of 6.2 months. Long-term integrity, technical and clinical outcomes were assessed. Results: All patients were symptomatic from their dissections. Presenting symptoms included TIAs, persistent pain, hemispheric infarcts, and SAH. Spontaneous (3), traumatic (2), and iatrogenic (1) etiologies were responsible for dissections. Dissections were treated with single (n=5) or overlapping (n=1) Neuroform stents. One patient required 3 tandem stents to reconstruct a long segment dissection. Technical success was achieved in all patients (100%) with no residual fl ow limitation. Dissection related mean stenosis improved from 84% pre-procedure to 26% and 9% on post-procedure and follow-up imaging respectively. There were no recurrent TIAs, infarcts, or subarachnoid hemorrhages. There were no long term complications.

In certain cases of dissections affecting tortuous and redundant vasculature, Neuroform stent appears to be a safe option for the endovascular management. Background: Gioblastoma multiforme is the most common primary malignant brain tumor in adults. Accurate diagnosis is important for the establishment of therapy and prognosis. However, diagnosis is often diffi cult as this entity can display various imaging characteristics depending upon its histological structure and growth pattern. Imaging Findings: We exemplify atypical imaging fi ndings in six cases of histologically confi rmed glioblastoma. Imaging features include lack of enhancement after contrast administration, primarily cystic or intraventricular growth pattern, subependymal and subarachnoidal spread as well as negative PET fi ndings. We correlate imaging fi ndings and histological structure to explain the displayed atypical MR morphology and signal properties. We illustrate how to improve diagnosic accuracy with the help of advanced imaging techniques such as MR spectroscopy, diffusion weighted imaging and perfusion weighted imaging. Conclusion: Atypical glioblastoma should be considered as a differential diagnosis in cerebral space occupying lesions with equivocal clinical and imaging fi ndings. Diagnosis of atypical glioblastoma can be improved by the use of advanced MR imaging techniques.

Imaging in tropical infections of the brain J. Singh, R. Kulkarni; Pune/ IN (joshitasingh@hotmail.com) Learning Objectives: To depict the various infective brain pathologies commonly encountered in the tropical settings in India. To illustrate the various imaging features of these infections. Background: Tackling neuro-infections constitute an ever growing challenge to the radiologist and the physician alike. They continue to be a major cause of morbidity and mortality with evolving clinical and imaging profi les as the infective organisms adapt to more and more drug regimes. B D E F A G Procedure Details: We reviewed and compiled the imaging features of various commonly encountered brain infections in India. Patients with tuberculosis, neurocysticercosis, chickungunya fever, dengue fever, Japanese B encephalitis, Herpes simplex encephalitis, neurobrucellosis and fungal infections were included in the study group. Opportunistic infections in immunocompromised patients were also included in the study group. In this exhibit, we discuss the imaging features and the differential diagnosis of each of these conditions. Areas of restricted diffusion not confi rming to any vascular territory in patients of chickungunya fever and demyelinating lesions in dengue fever were some uncommon characteristic imaging features seen in our study group. Conclusion: Imaging plays a crucial role in management of neuro-infections.

Characteristic clinical and imaging features may obviate the need for further investigations in the cost constrained or epidemic settings. Background: Central nervous system involvement with malignant lymphoma, whether primary or secondary is an uncommon disease, which is increasingly seen in immunocompromised individuals, particularly secondary to HIV or other haematological malignancies. There is high morbidity and mortality associated with cerebral lymphomas. Imaging is important in diagnosing lymphomas and differentiating it from other mimics. CT is often the fi rst imaging modality, but MRI is the most useful modality. Imaging Findings: The pictorial review illustrates the spectrum of imaging fi ndings seen in primary and secondary cerebral lymphomas seen in different imaging modalities, with particular emphasis in MRI. CT scan shows hyperdense lesion, predominantly in the subspendymal region. MRI shows solid, enhancing lesions in subspendymal region. Ring enhancement is a feature of lymphomas arising in immunocompromised individuals. Differential diagnosis of lymphomas include other solid tumours, toxoplasmosis, abscesses. The review discusses the salient features of each of these differential diagnosis. Conclusion: Primary and secondary central nervous system lymphomas have characteristic appearances in CT and MRI scans. B lymphomas are the commonest to affect the brain. Lymphomas are commonly seen in the subspendymal region. Primary and secondary lymphomas have different features in imaging. Intense enhancement is a feature of Ring enhancement.

Radiological spectrum of lesions involving the hippocampus A. Rovira-Cañellas 1 , A. Rovira-Gols 2 , C. Auger 1 , N. Bargalló 1 , J. Alvarez-Linera 3 ;

1 Barcelona/ES, 2 Sabadell/ES, Learning Objectives: To illustrate the radiological fi ndings of several lesions that predominantly affect the hippocampus. Background: The hippocampus, which forms a part of the limbic system, has a crucial role in cognition and memory, particularly in the formation of long-term memory. In vivo visualization of the hippocampus became possible with the advent of MR imaging, which has allowed the identifi cation of a variety of lesions that mainly affects this formation. Imaging Findings: Many of the MR imaging examinations performed to identify structural abnormalities of the hippocampus are obtained in patients with temporal lobe epilepsy (medial temporal lobe sclerosis) and several forms of primary neurodegenerative dementia, particularly those of the Alzheimer type (hippocampus atrophy). However, hippocampal changes can occur in a broad spectrum of disorders beyond dementia and epilepsy, including ischemic lesions (infarction within the posterior cerebral artery territory), primary brain tumours, infl ammatory and infectious diseases (viral and paraneoplastic encephalitis, demyelinating lesions), vascular malformations (cavernoma, arterio-venous malformation), and focal cortical dysplasia, as well as several neuropsychiatric disorders (schizophrenia, post-traumatic depression). The hippocampus may also be selectively affected in patients with neurofi bromatosis type I, and in the acute phase of transient global amnesia and status epilepticus.

The hippocampus can be affected by a variety of processes that may present similar clinical fi ndings. MR imaging establishes the proper differential diagnosis with a relatively high specifi city when a suitable imaging protocol is used.

The correlation between the fractional anisotropy (FA) value and the pathologic change at different stages of spinal cord injury in rats N. Chen, K. Li; Beijing/ CN (cnddcndd@yahoo.com) Purpose: To evaluate the correlation between the fractional anisotropy (FA) value and the pathologic change at different stages of spinal cord injury in rats.

A total of 32 SD rats were medially divided into 4 groups. Each group (n=8) received a completely transverse injury at the lever of T6. On each group, diffusion tensor imaging was performed by using a 1. 

necessary. The images were analyzed for patterns of involvement, frequencies and differential diagnosis entertained. Results: The dorsolumbar region was commonly affected. In 45 patients, more than two regions were involved. Contiguous involvement of adjacent regions was more common than skip lesions. There were three patterns of involvement: disk-vertebral lesion, those confi ned to the body and posterior arch lesion. Lesions sparing disks (40%) were nearly as common as those involving both body and disc (47%). Nearly 90% of disk-vertebral lesions were associated with paraspinal/epidural abscesses or cord compression, especially at the dorsolumbar junction. Body lesions were also associated a high incidence (70%) of abscesses and cord compression. One-third of these lesions were confi ned to the body (thus mimicking secondaries, lymphoma). Isolated posteriro arch involvement occurred in 13 patients. Conclusion: Spinal tuberculosis has a varied presentation and can mimic any disease of the vertebral column. Isolated pedicle involvement and multifocal body involvement can closely mimic malignancy. Purpose: MRI has become a critical diagnostic imaging modality for spinal disorders. Spine arthrodesis and arthroplasty devices are known to result in signifi cant artifacts on MRI. We assessed and compared the artifact resulting from four different biomaterials utilized in clinical arthroplasty devices when encountered in the same shape. Methods and Materials: Sheep lumbar spinal segments were harvested and the lower lumbar discs excised. Circular discs of the various materials were then used to fi ll the spaces. Polyethylene, Medical Ceramic, Titanium, and Chrome cobalt (CoCr) alloy discs were used. Images were obtained with a General Electric 1.5 T MRI unit in both sagital and axial sequences. The scans were reviewed by the authors (neuroradiologist and orthopedist) and the distortion graded between the various materials. The area of fi eld distortion and the device dimensions were also compared. Results: The distortion from polyethylene was the least severe and CoCr was the most severe on both sagital and axial MRI scans. Ceramic alone was mild with Titanium causing an intermediate fi eld artifact. The CoCr disc resulted in severe artifact on the MRI image, resulting in artifact which was twice the dimension of the disc.

The choice of biomaterial for spinal implants for arthrodesis and arthroplasty, in addition to design shape, will have a profound effect on the magnitude of MRI artifact and on whether MRI images are of any clinical utility after spinal surgical reconstruction.

Magnetic 

Evaluation of spinal vessels with CE angioMR in suspicion of vertebral canal AVM K. Gruszczynska 1 , J. Baron 1 , W. Brojacz 2 , P. There is a degree of overlap between the imaging fi ndings in these conditions. However, certain fi ndings are helpful pointers towards the diagnosis of specifi c connective tissue diseases and conditions associated with vasculitis. Examples of spinal cord compression, focal cerebral infarcts, multifocal white matter lesions, venous sinus thrombosis, intracerebral and subarachnoid haemorrhage, aneurysm, cerebral abscess, cytotoxic and vasogenic oedema in such cases are shown on CT and MR images.

The purpose of this exhibit is to illustrate the spectrum of neuroradiological imaging fi ndings in connective tissue diseases and vasculitides, and to show features that allow the radiologist to distinguish between the differential diagnoses.

Neuroimaging manifestations in Von Hippel Lindau disease: Emphasis on unusual fi ndings A. Patsalides 1 , E. Tzatha 2 , N. Patronas 2 ; 1 Washington, DC/US, 2 Bethesda, MD/US (apatsalides@cc.nih.gov) Learning Objectives: In this exhibit, we present the neuroimaging manifestations of VHL disease, emphasizing on the unusual fi ndings. Background: Von-Hippel Lindau (VHL) disease is an autosomal dominant disorder with incomplete penetrance. Neuroimaging manifestations include the presence of hemangioblastomas in the retina, brain and spine as well as endolymphatic sac tumors (ELST). Imaging Findings: Common and unusual imaging features of hemangioblastomas in the cerebellum, brainstem and spinal cord are presented and evolution in time is assessed. We show hemangioblastomas in uncommon locations such as the suprasellar area, cerebral hemispheres, internal auditory canals, cauda equina and leptomeninges, mimicking other tumors. We present the imaging abnormalities of ELST and the range of involvement of the petrous bone as well as a variety of retinal hemangioblastomas and their complications.

The spectrum of neuroimaging manifestations in patients with VHL disease is wide. Awareness of the variety of imaging fi ndings and evolution in time is important for the complete understanding of this entity.

Lipomas, dermoids and epidermoids of the brain and spine: A pictorial review S.B. Lachanis, A.N. Chalazonitis, J. Pontikis, G. Tsimitselis, N. Ptohis, I. Tzovara; Athens/GR (red-rad@ath.forthnet.gr)

Learning Objectives: 1. To pictorially review the MR imaging features of CNS lipomas, epidermoids and dermoids with various sequences. 2. To describe their distinguishing imaging features aiding their differential diagnostic approach. 3. To underline potential pitfalls in their differential diagnosis. Background: Lipomas, dermoids and epidermoids of the brain and spine, although rarely encountered, enter in the differential diagnosis of many other CNS tumors. Although their embryology is different, these lesions share a common feature: they represent "tissues at a false place", as mesencymal and cutaneous ectoderm tis-

sues within CNS structures. Imaging Findings: In this exhibit, we present a great number of cases of CNS lipomas, dermoids and epidermoids. All cases have been drawn up from our teaching fi les. Imaging characteristics (with all conventional and newer MR sequences), together with their differential diagnosis are pictorially presented. Potential pitfalls in their differential diagnosis will also be discussed. Conclusion: Lipomas, dermoids, and epidermoids of the CNS have distinguishing radiological appearance concerning especially their MRI imaging characteristics. By appreciating these, together with their site of predilection and affected age spectrum, any radiologist can reach the specifi c diagnosis in a majority of cases. Purpose: Central and/or peripheral nervous system involvement (neuroborreliosis) is frequent in Lyme disease and is often the fi rst presentation. Aspecifi c white matter lesions on T2-weighted images (WI) in neuroborreliosis have been published in the literature. Cranial nerve enhancement was frequently observed in our series. We present the magnetic resonance (MR) imaging fi ndings in 9 patients with proven neuroborreliosis. Methods and Materials: Nine patients with positive serology for Lyme were included in this retrospective study. 8 MR studies of the brain, 1 of the lumbar spine and 1 of the cervical spine were performed. MR imaging of the brain consisted of T1-WI, T2-WI, fl uid-attenuated inversion recovery (FLAIR) and contrast enhanced T1-WI. Spinal studies included T2-WI, as well as T1-WI before and after gadolinium injection. Results: One brain study and the MR examination of the cervical spine showed no abnormalities. Five brain studies displayed aspecifi c white matter lesions. In four patients, cranial nerve enhancement (3 vestibulocochlear nerve, 2 oculomotor nerve, 2 trigeminal nerve, 1 facial nerve, and 1 glossopharyngeal nerve) was observed. In one patient, right hemispheric cerebellitis and leptomeningeal enhancement was described. MR of the lumbar spine showed polyradiculitis of the cauda equina. Conclusion: Aspecifi c white matter abnormalities are frequently observed in patients suspected for neuroborreliosis. Cranial nerve enhancement, cerebellitis, and polyradiculitis may narrow the differential diagnosis in these patients and neuroborreliosis must be considered when these fi ndings are encoutered, especially in endemic regions.

Contrast 

High-resolution ultrasound of infl ammatory bowel diseases in children U. Zaleska-Dorobisz, A. Stawarski, D. Sokolowska, B. Iwańczak, K. Moroń; Wrocław/PL (atd@vassurg.am.wroc.pl) Purpose: To present the usefulness of high-frequency standard and Doppler ultrasound in the diagnosis and therapy monitoring of infl ammatory bowel diseases (IBD) in children.

We studied 95 children, with mean age 13.5 years, with infl ammatory bowel diseases: thirty-fi ve with Crohn Disease (CD), 41 with colitis ulcerosa (CU), 19 with other IBD. We performed high-resolution 2D sonography to evaluate the bowel-wall thickness. Intraparietal vascularisation was assessed with color Doppler. Superior or inferior mesenteric arteries fl ow, mean velocity, RI (resistance index) were measured in all patients. We compared clinical active disease, ultrasounds and colonoscopy. Results: CD predominantly involved the small intestine. The bowel wall was greatly thickened more than 8-10 mm. Mucosal ulcerations penetrated into the wall in 25 children; in 13 we found fi stulas and peritoneal abscesses. The mesentery and fat around the bowel was thickened in all children. UC was limited to the left colon. The colon wall was thickened more than 5-11 mm. Mural infl ammation was located in the mucosal surface with superfi cial ulcerations and pseudo polyps (50%). Color Doppler revealed hyperemia with increased vascular supply of the involved bowel wall. The RI was signifi cantly lower in active disease. After treatment, RI values increased signifi cantly (p < 0.005). Conclusion: High-resolution and Doppler sonography can detect bowel-wall abnormalities in most IBD in children. Doppler fl ow parameters in mesenteric arteries correlated strongly with disease activity. Doppler US could be used for monitoring the treatment effi ciency.

Single-shot MRCP in the evaluation of pancreaticobiliary disease in children S. Fitoz, A. Erden, S. Boruban; Ankara/TR 

Balloon dilatation of oesophageal strictures following surgical repair of oesophageal atresia F.A. Kazmi, D. Roebuck; London/UK (drfkazmi@doctors.net.uk) Learning Objectives: We describe and illustrate the technique, indications and complications of balloon dilatation of oesophageal strictures following surgical repair of oesophageal atresia based on a series of 30 patients.

Background: Balloon dilatation of oesophageal strictures is well described in the adult literature. However, its role in the paediatric population after repair of oesophageal anomalies is less well established. Post operative stricture occurs in 30-50% of patients with oesophageal atresia. This carries a high risk of malnutrition and aspiration to the lungs. It is the most common post surgical complication and typically occurs at the primary site of anastomosis. At our institute, we have one of the largest case series of patients undergoing balloon dilatation of strictures after surgical repair of oesophageal atresia. Procedure Details: All procedures were carried out under general anaesthetic. The oesophageal lumen was opacifi ed with water soluble contrast to correctly identify the location of the stricture. A 4 F catheter and hydrophilic guidewire were passed through the mouth and manipulated under fl uoroscopic guidance across the stricture and into the stomach. A balloon catheter (15-20 mm in diameter) and 3-6 cm long was passed over the guidewire and positioned across the stricture. The balloon was slowly infl ated with diluted water soluble contrast under fl uoroscopy until the waist on the balloon was obliterated. A post procedure oesophagram was then performed to check for oesophageal rupture. Conclusion: Balloon dilatation of strictures following surgical repair of oesophageal atresia is clinically effective, safe, relatively atraumatic and is without high risk of complications.

Infl 

A total of 84 children were enrolled: 56 with Crohn's disease (CD) and ulcerative colitis (UC) and 28 healthy siblings as controls. Lumbar spine BMD was measured by DXA and Z-scores were obtained by comparison with age-and sex-matched normal values. Bone age was measured in each patient by the method of Greulich and Pyle and aBMD was calculated again using bone age instead of chronological age. Multiple regression analysis was used to evaluate the relationship between IBD and potential risk factors. Results: Children with CD and UC differed for corticosteroid exposure. Total duration of therapy (p=0.009), cumulative (p=0.03) and daily dose (p=0.004) of prednisone were signifi cantly higher in patient with UC. No signifi cant difference was found between CD and UC aBMD. Prevalence of low BMD (Z score<-2) was higher for IBD patients respect to controls (p=0.026). aBMD Z scores were then calculated using bone age instead of chronological age and aBMD was found signifi cantly low in UC patients (p < 0.01).

Conclusion: Children with IBD should be evaluated for BMD and a corret interpretation of DXA results is important for identifying children at real risk for osteoporosis. Low BMD has a high prevalence in children with IBD, but it has to be assessed using bone age instead of chronological age to avoid overestimation. Purpose: To present an MR imaging protocol for the evaluation of IIB disease and to assess its effi cacy in evaluating disease activity. Methods and Materials: MR imaging of the small bowel was prospectively performed in 15 patients (aged 9-15 years) with known or suspected IIB disease. 2.5 lt of water solution with herbal fi bers was administered over 4hours through a nasogastric tube prior to MR examination. Patients were scanned in the prone position using coronal and axial thin-slice (1.5 mm) 3D T1-weighted GE and T2-weighted bFFE fat-suppressed sequences followed by dynamic study after contrast administration. Quality of imaging, including small bowel distention, wall conspicuity, motion and susceptibility artifacts, was evaluated by two observers in consensus. Disease activity was evaluated by presence and degree of mural enhancement and edema.

The procedure was well tolerated by all patients. Quality of imaging was considered excellent (n=10 patients), satisfactory (n=5) and non-satisfactory (n=0). Imaging fi ndings included: wall thickening (> 4 mm) of the terminal ileum (n=11), jejunum loops (n=5), large bowel (n=3) and stomach (n=1), and luminal narrowing (n=2). Seven patients showed early increased wall enhancement, implying active infl ammation, whereas four patients exhibited delayed mild enhancement of bowel

wall consistent with inactive disease. Extraluminal manifestations included mesenteric adenopathy (n=6), perienteric fi brofatty proliferation (n=6), ascites (n=2) and patulous ileocecal valve (n=2). Conclusion: MRI of the small bowel, using the current imaging protocol, is a welltolerable, non-ionising method for evaluating the presence, extent, activity and extraluminal manifestations of IIB disease in pediatric patients.

Detection of tree-in-bud sign in cystic fi brosis by volumetric thin-section low-dose MDCT: Incidence, natural history and correlation to morphologic score and spirometry K.M. Unsinn, H. Ellemunter, J. Eder, W.R. Jaschke, M.C. Freund; Innsbruck/AT Purpose: To determine the incidence of tree-in-bud sign (indicating involvement of the peripheral bronchioles by infection and infl ammation) in patients with cystic fi brosis by volumetric thin-section low-dose MDCT. To evaluate the natural history (i.e. reversibility) of tree-in-bud sign in patients with cystic fi brosis. To correlate the tree-in-bud sign to CT-morphology measured by Bhalla score and to spirometry. Methods and Materials: All patients had proven cystic fi brosis (CF). Volumetric low-dose multidetector (4, 16, or 64) row spiral CT (MDCT) of the chest was performed in 40 patients (5-50 years) every second year without contrast administration in supine position at end-inspiration during single breath-hold with following scan parameters: contiguous 1.25 mm slice thickness/intervall, 120 kV, 10 mA, 0.8 sec rotation time/360°, standard and lung reconstuction algorithm. Dose-length product (DLP) (mGy•cm) was recorded. Two radiologists reviewed all images and arrived at consensus opinion regarding incidence and natural history (i.e. reversibility) of tree-in-bud sign with correlation to CT-morphology measured by Bhalla score and to spirometry.

The tree-in-bud sign was seen in 8/40 patients (20%) and occured at higher age (p < 0.05), at higher level of CT-morphological involvement as measured by Bhalla score and at higher level of functional pulmonary impairment measured by spirometry (p < 0.05). In this patient population, the tree-in-bud sign was never reversible. Conversion of recorded DLP (range) 08.50-22.52 (mGy•cm) resulted an effective dose (range) 0.12-0.33 (mSv).

The tree-in-bud sign represents a non-reversible sign in patients with CF occuring in later stage of disease and presumably indicating involvement of bronchioles.

Apneac oxygenation using CPAP to perform computed tomography of the thorax in paediatric patients B. Tagliaferri, U. Sonvico, E. Battaglia, M. Del Sante, F. Boioli; Milan/IT (btagliafer@sirm.org)

Purpose: Evaluation of the diagnostic accuracy of multi-slice spiral CT (MSCT) high-resolution computed tomography (HRCT) in paediatric patients for the examination of the pulmonary parenchyma, maintaining continuous expansion of the lung (apneac oxygenation) through the use of CPAP. Methods and Materials: An evaluation of 35 patients between the ages of 15 days and 2 years was conducted using MSCT-HRCT. Patients were examined with the Siemens Somaton Sensation 16-CT scanner, using technical parameters enabling exposure to low doses, and ventilation was ensured manually using an Ayres "T" tube for the time necessary for the preparation of the child until the end of the period of apnea. The examinations were carried out with and without PEEP, with a mean duration of 1 minute. Results: In all the patients examined, the thorax was kept immobile and continually extended, enabling the avoidance of interpretative errors, facilitating the differentiation of pulmonary pathology with extreme precision, distinguishing the types of bronchial obstruction associated with air trapping and facilitating the evaluation of the lower segments of the lung parenchyma, where collapse often occurs. The modifi cation of some of the technical parameters (kV and mAs) enabled us, furthermore, to carry out examinations at low doses in compliance with the European radioprotection standards.

The pulmonary hyper-expansion obtained with this method enables the MSCT-HRCT to be performed in paediatric patients, giving a correct evaluation of the pulmonary parenchyma without the use of artifi cial respirators. 

Overview of paediatric orbital pathology: A pictorial review S. Nayak, D. Nayak; Leeds, West Yorkshire/UK (sanjeevnayak@hotmail.com)

The spectrum of ocular and orbital pathology in the paediatric age group is quite different from that of adults. Imaging studies serve an important role in the diagnosis and management of many of these abnormalities. Systemic approach is required to understand the classifi cation and imaging features of orbital pathology. We have described them according to the three orbital compartments, namely, the globe/optic nerve sheath, intraconal and extraconal lesions. This extensive pictorial review outlines the various abnormalities of the paediatric eye and orbit for which imaging studies are often required, including infection, neoplasm, infl ammation and infi ltration, developmental anomalies, and trauma. Imaging included in this review includes the relevant plain radiography, CT, ultrasound and MRI features of various pathologies. Additionally, the pertinent fi ndings are correlated with pictorial description of the relevant histopathology, fundoscopy features and relevant clinical ocular photographs. Correlation of the results of imaging studies with pertinent clinical information allows the determination of specifi c diagnoses in most instances of paediatric orbital pathology. Control children were neurologically and developmentally normal and also showed normal MRI. MRI was performed from 0 to 5 years of corrected age in both groups. We measured the AP diameter of the pons, the tegmentum and basis pontis, and corpus callosum length using T1-weighted midsagittal image. Results: Pontine diameters in all regions were signifi cantly smaller in the PVL group than in the control group. Pontine diameters in the PVL group and control group were 1.66±0.21 (SD) and 1.87±0.23 mm (P < 0.001), respectively; tegmentum diameters were 1.23±0.20 and 1.36±0.19 (P < 0.001), respectively; basis diameters were 0.42±0.10 and 0.51±0.14 (P < 0.001), respectively; and the corpus callosum lengths were 5.02±0.90 and 5.51±0.76, (P < 0.001), respectively. When the agerelated pontine diameter differences were examined, there was signifi cant difference in pontine diameters after 12 months of age.

We proved that pontine diameter in patients suffering PVL is significantly smaller than normal control. Purpose: Methylmalonic acidemia (MMA) often presents with nonspecifi c neurological symptoms that leads to different imaging work-ups. Better recognition of fi ndings of brain imaging (CT/MRI) helps physicians suspect to MMA diagnosis in earlier reversible stages of the disease. Methods and Materials: Fifty-two brain images of the patients with confi rmed diagnosis of MMA including 47 MR and 5 CT images were reviewed. The clinical data were also registered for each patient. The frequency of different radiological fi ndings were compared according to age,gender,clinical presenting symptom and duration of treatment. Results: Fourteen patients (26.9%) had normal brain images.The most common fi ndings of the images were (in order of frequency): ventricular dilation (32.7%), diffuse cortical atrophy (sulci dilation)(28.8%), periventricular white matter change (23.1%), corpus callosum thinning (15.4%), subcortical white matter lesions (11.5%), local cortical atrophy (7.7%) and cerebellar atrophy (7.7%). Basal ganglia calcifi cation was seen in 2 patients both of whom presented clinically in neonacy. Treatment duration seems to have an improving effect on the severity of ventricular dilation (less severity in those who have received the classic treatment for more than one year). Children who presented with psychomotor delay had usually multiple radiological fi ndings while few fi ndings were seen among those presented with loss of consciousness and those detected by neonatal screening. Conclusion: In addition to ventricular and sulci widening, myelination abnormality and basal ganglia changes, some other fi ndings are expected and rise the suspicion to MMA including corpus callosum thinning, brain stem thinning, signal change due to focal infarct, bright signal in centrum semioval and putamen calcification. Treatment with adequate duration may improve or prevent some structural changes in CNS. Learning Objectives: To describe the principal location of facial fractures in pediatric patients and their radiologic appearance. To discuss the optimal imaging work-up for detection of these fractures in children, with emphasis on the important role of CT. To describe our experience in this fi eld in the last 10 years: epidemiology and main mechanisms of trauma. Background: Trauma is one of the main causes of morbidity and mortality in the pediatric age group, craniofacial fractures being accountable in a signifi cant part. There is great disparity in the available epidemiologic data and scant radiologic literature on this important subject. Interpretation of facial radiographs is specially challenging in children, and CT is required in many cases; therefore, we must be familiarized with the unique characteristics of these fractures. We retrospectively reviewed facial fractures attended in our institution in the last 10 years. The total amounted to 320 diagnosed fractures in 282 patients < 16 years. We analyzed the mechanism of trauma, patient age and sex, fracture location, and radiologic features. We fulfi lled a bibliographic revision and compared our results to those in the literature. Imaging Findings: The most common were nasal fractures, succeeded by mandibular and orbital fractures. Zygomatic, nasoetmoidal, frontal and panfacial fractures were found to be infrequent. The sex ratio was 1.7:1 (male/female). The main causes were accidental falls, followed by aggressions, motor-vehicle crashes, and sports accidents. Conclusion: Facial fractures in the pediatric age group have special characteristics, and therefore require subject-specifi c knowledge of the diagnosis, management, and follow-up. For the follow-up, 4 groups were defi ned: newborns with (1) lethal postnatal course (2) intensive respiratory care > 6 days and/or pulmonary hypertension (3) intensive respiratory care < 6 days, and (4) no need for additional respiratory support.

In fetuses with oligohydramnios, fetal lung volumes were signifi cantly reduced (p < 0.01). The mean defi cit of lung volumes was 31% compared to normals. Fetuses with a modal defi cit of 58.7% of lung volume deceased postnatally. Reduced signal intensity of lung tissue was associated with lethal outcome in 6 of 8 newborns. Differences of lung volumes and signal intensities between the groups 2-4 were less pronounced. Fetuses with a high risk of pulmonary hypoplasia (group 2) showed signifi cantly reduced amniotic fl uid volumes, early onset and a long persistence of oligohydramnios. Conclusion: Fetal MR can reveal the degree of pulmonary hypoplasia in fetuses with oligohydramnios. Reduction of fetal lung volumes over 50% of the expected value together with pronounced darkness of lung tissue on T2-weighted MR sequences is highly conspicuous for lethal outcome.

Magnetic resonance and computed tomography fi ndings in childhood Background: TB still ranks as one of the most important communicable diseases and represents a major global health problem. Although pulmonary TB tends to be the most common form of tuberculosis, the highest mortality and morbidity occurs with TB of central nervous system (CNS TB), which develops in 4% of children with tuberculosis and has an high fatality rate and causes serious sequelae, especially during childhood. Imaging Findings: Available imaging CT and MR studies of 18 patients (11 females, 7 males; mean age: 45.72 months) were retrospectively reviewed. All patients showed a basilar enhancement. Other fi ndings were hydrocephalus (61%), intracranial tuberculomas (17%), and other nodular (11%) and ischemic lesions (11%). Edema, either perilesional or diffuse, was found in 7/18 patients. Severe ventricular dilatation was observed in 9/18 cases. Two patients, with fatal involvement, showed severe hydrocephalus associated, respectively, with extended ischemic areas and intraventricular haemorrhage. Conclusion: Cross-sectional imaging, along with clinical data, may provide useful clues in the early diagnosis of CNS-TB, and may helpful in preventing unnecessary morbidity and mortality.

Head and neck tumors in the pediatric age group -more than lymph nodes to be found G.K. Schneider, K. Altmeyer, P. Fries, A. Massmann, T. Krenn, N. Graf; Homburg a.d. Saar/DE (ragsne@med-rz.uni-sb.de) Learning Objectives: This exhibit will present the wide spectrum of head and neck masses in children. Special consideration will be given to describe the lesions DDX according to their anatomic localization. Background: Masses of the head and neck area are a commonly encountered problem in daily practice. The aim of this exhibit is to review DDX of head and neck tumors in children with special regard to their anatomic localization. MRI and CT images will demonstrate the range of lesions from infl ammation to lymphoma, soft tissue tumors, and vascular abnormalities. Imaging Findings: The exhibit will review the different anatomic spaces to enable the reader to properly allocate a mass to its compartment. DDX will be explained with regards to their typical localization, imaging fi ndings and their clinical appearance. MRI and when it is useful for DDX CT images will be demonstrated in case presentations. A special emphasis will be laid on pitfalls such as vessel abnormalities or pseudotumors. Finally, readers will have the opportunity to test their knowledge in some quiz cases. Conclusion: DDX of masses in the head and neck region of children goes far beyond simple lymph node enlargement versus lymphoma. Depending on its localization, cervical cysts or tumors of neural origin may come into focus. Soft tissue or bone tumors, pseudotumors, and abscess formations or vessel abnormalities all may present as circumscribed lesions. MRI allows for exact tumor localization, and together with CT and ceMRA may identify lesions that need to undergo biopsy.

Fetal MRI evaluation of anomalies of the neural tube and spine C. Martín, A. Lüttich, C. Escofet, A. Martín, I. Delgado, S. Perez, C. Durán;

Purpose: To analyze the neural tube and spinal column anomalies detected prenatally at our centre over the last 10 years and evaluate the impact of fetal MRI in the diagnosis. Methods and Materials: Thirty fetuses with anomalies of the neural tube and spine were studied. All patients underwent obstetric US examination. Intrauterine MRI was performed in 22 cases; in the remaining 8, MRI was not performed because indications went unobserved at US or further examination was considered unnecessary. MRI was performed on a 1.5 Tesla unit using ultrafast half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequences. Images were analyzed by a pediatric radiologist and the fi ndings were compared to those of US. All anomalies were confi rmed after birth or at autopsy. Results: The anomalies observed were acrania (n=3), encephalocele (n=3), iniencephaly (n=1), spina bifi da (n=8), diastomatomyelia (n=1), hemivertebra (n=3), kyphoscoliosis (n=2), amniotic band syndrome (n=1), osseous dysplasia with spinal involvement (n=3), caudal regression syndrome (n=1), sacrococcygeal teratoma (n=3), and conjoined twins (n=1). Neural tube and spinal column anomalies were associated to anomalies in other organs in 17 cases. Fetal MR provided additional information in 10 (45%) cases, and changed the therapeutic approach in 6 (27%). Conclusion: Prenatal diagnosis of neural tube and spinal column anomalies can predict fetal viability, orient the prognosis and management of the newborn, and has implications for genetic counseling. MR is a noninvasive method of fetal examination that provides additional information to US. in a factor of 5-10 if appropriate procedure protocol is used, with optimised setting for the X-ray system. Purpose: To assess Magnetic Resonance Urography (MRU) in the morphologic evaluation of suspected urinary tract obstruction in infants and children. To try to evaluate the correlation between functional fi ndings in MRU and nuclear medicine. Methods and Materials: 15 patients with sonographicallly suspected urinary tract obstruction were studied with MRU (1.5 T), intravenous urography and nuclear medicine. Procedure Details: saline solution (NaCl 9%, 10 mL/kg) and low-dose furosemide (1 mg/kg) were administered before beginning unenhanced MRU (heavily T2-W sequences). After 15 minutes, 0.1 mmol/kg Gd-DTPA was administrated to coincide with the maximal diuretic effect, and dynamic enhanced MRU (coronal 3D FRGE sequences) was performed.

The obstruction site and cause were detected in all cases by MR examination. Diagnosis of the 30 kidneys includes: normal system (12), duplex system (4), pyeloureteral junction stenosis (9), ureterocele (3), ureteric ectopia (2), multicystic dysplastic kidney (1), megaureter (2), ureteral kinking (2), horseshoe kidney (2). Time difference of 180 seconds in the excretion of normal and pathologic kidneys showed good correlation with the diagnosis of obstruction in nuclear medicine. Conclusion: MRU provides very high quality images. Additional benefi ts include renal arteries evaluation and preprocedural planning for surgery. MRU is a nonionizing imaging technique that allows both functional and morphologic evaluation in the same procedure and could replace other imaging modalities.

The whole spectrum of sonographic patterns of normal and abnormal renal pyramids in infancy and childhood M. Vakaki, P. Papadoniou, A. Simopoulos, K. Tavernaraki, G. Pitsoulakis, C. Koumanidou; Athens/GR (geop@hol.gr)

Learning Objectives: To present the wide spectrum of sonographic patterns of renal pyramids in physiologic, as well as pathologic conditions that affect the renal medulla of pediatric patients. To emphasize the role of sonography, correlating the imaging fi ndings with etiology, which should be the basis for the appropriate differential diagnosis. Background: It is well-known that the sonographic appearance of the developing 486 B D E F A G kidney differs from that in adults and changes from birth to adolescence. One of the characteristic unique features of the pediatric kidney is the hypoechoic appearance of its prominent medullary pyramids. Various conditions modify this normal appearance. Furthermore, the disease processes that affect the renal medulla in children differ from those in adults. Imaging Findings: The various sonographic patterns of normal and abnormal renal pyramids are illustrated. Anatomic details, histopathology and suggested pathophysiologic mechanisms of the different causative pathologic entities are presented. These conditions represent a heterogeneous group of disorders and include the normal transient neonatal renal medullary hyperechogenicity, the severe obstructive urinary stasis and intratubular refl ux, polycystic kidney diseases (mainly autosomal recessive polycystic disease), renal candidiasis, sickle cell anemia, the various common and rare causes and types of nephrocalcinosis, etc. Conclusion: Renal sonography with state-of-the-art US equipment is very sensitive in the imaging study of renal medullary pyramids in childhood. Knowledge of the specifi c sonographic features of the different pathologies affecting the renal pyramids supplemented by the necessary clinical information allows the narrowing of the differential diagnosis directing further diagnostic investigation, when necessary.

The role of MR imaging in the pre-surgical evaluation of pre-sinusoidal hypertension secondary to portal cavernomatous transformation in children F. Guerra-Gutiérrez, J. Fernández-Cuadrado, J. Gomez-Patiño, A. Alonso-Torres, M. López-Santamaría, N. Leal; Madrid/ES (fl aguers@hotmail.com)

Learning Objectives: To demonstrate the utility of Magnetic Resonance Angiography (MRA) in the pre-surgical evaluation of pre-sinusoidal hypertension due to portal cavernomatous transformation (PHPCT) in children.

Background: Children with PHPCT may be treated by means of programmed surgery, and a pre-surgical imaging evaluation is crucial to defi ne the venous obstructive pattern, and, subsequently, to choose an appropriate surgical strategy.

In that purpose, commonly, these children underwent a conventional angiography, which is an invasive technique. Imaging Findings: Twenty-two children with PHPCT were evaluated. They all underwent a MRA previous to programmed surgery in the past 10 years. We describe four major venous patterns: 1) principal portal vein (PPV) obstruction with patent and connected to each other superior mesenteric vein (SMV) and splenic vein (SV) (n=14); 2) PPV obstruction with thrombosis of SMV and patent SV (n=7); 3) generalized hypoplasia of the splachnic venous system (n=1); 4) any of the previous patterns with normal intrahepatic portal vein (n=5). The surgical procedure was chosen as follows: mesenteric-caval shunt with autologous jugular vein graft (n=11) in the case of the fi rst pattern; distal splenorenal shunt (n=5) and proximal splenorenal shunt, both indicated for the second pattern; mesenteric-left portal vein shunt (Rex) for the fi rst pattern in association with the fourth pattern; non-derivative surgery (n=1) in the case of the third pattern. Conclusion: MRA is a useful tool in the pre-surgical evaluation of children with HPCPT. It gives accurate information that helps the surgeon to choose the most suitable surgical procedure.

Subcarinal left pulmonary artery sling in fi ve patients: Assessing anatomical relationship between air-way and left subcarinal pulmonary artery sling and associated with tracheobronchial anomaly K. Choo 1 , Y. Kim 2 , M. Lee 1 ; 1 Pusan/KR, 2 Pucheon, Kyunggi-do/KR Purpose: The purpose of our study is to assess anatomical relationship between air-way and subcarinal left pulmonary artery sling and associated with tracheobronchial anomaly.

We present chest radiography, CT and echocardiographic fi ndings of subcarinal left pulmonary sling in 5 patients (2 male, 3 female, mean age: 14.8 months). All patients had respiratory symptoms. Echocardiography showed intracardiac anomaly such as VSD, ASD, pulmonary atresia in 4 patients and abnormal coursing left pulmonary artery in all patients. Single, 4-slice and 16 slice MDCT were performed and axial images with 3 dimensional reconstructions were used for evaluation of anatomical relationships of tracheobronchial anomaly associated with subcarinal left pulmonary artery sling in all patients. Results: One of the 5 patients had severe obstruction of left main bronchus by subcarinal left pulmonary sling, resulting in total atelectasis of Lt. lung, with basically normal bronchial branch pattern. Four of the 5 patients had about 50% obstruction of left main bronchus by subcarinal left pulmonary sling with associated bridging bronchus.

The subcarinal pulmonary sling could cause obstruction of left main bronchus and be often associated with tracheobronchial anomaly, including bridging bronchus. In addition, the CT scan using axial images and 3 dimensional reconstructions could help to assess anatomical relationship between air-way and subcarinal left pulmonary artery sling and associated with tracheobronchial anomaly. (n=15), and cystic lymphangiomas (n=8). The sonographic fi ndings are illustrated and differential diagnosis is discussed. All cases were confi rmed surgically, or with clinical/sonographic follow-up. Conclusion: Sonography has been shown to be particularly helpful in confi dently evaluating abnormalities of the thoracic and abdominal wall and optimal treatment planning. Pediatric radiologists, therefore, should be familiar with the embryology and anatomy, as well as with the sonographic features of various congenital and acquired pathologic disorders involving the thoracic and abdominal wall of children.

Imaging pediatric pseudo-malignancies: A retrospective review of 29 cases G. Castellazzi, D. Vanel, D. Couanet, C. Dufour, R.C. Sigal, C. Dromain; Villejuif/FR Purpose: Two per cent of the children referred to our cancer center have pseudomalignancy. The aim of this study was to analyze and correlate their clinical and radiological fi ndings. Methods and Materials: From 1990 to 2006, 98 patients with "pseudo" cancers, referred by well-trained clinicians, were seen. Twenty-nine had complete imaging and clinical history records and the fi nal diagnosis of proven non-malignant disease. There were 19 males and 10 females, between 1 and 17 years of age. The fi nal diagnoses were made through pathology (17), follow-up (12), and serologic analysis (1). Results: Frequent symptoms, variously combined and most frequently associated at the beginning, were: pain (17), fever (5), a mass (5), adenopathies (5), and walking diffi culties (3). One patient had two pseudo-malignancies. Thus, 30 lesions were studied with the following diagnoses: malignant bone tumor (9), lymphoma (5), nephroblastoma (3), neuroblastoma (3), soft tissue tumor (4), nervous tissue tumor (4), small bowell neuroendocrine (1), and undifferentiated nasopharyngeal carcinoma (1). 138 various radiological examinations were performed. There were in fact 15 infections, 7 traumatic lesions, 3 chronic diseases, 3 congenital lesions, and in 2 cases no disease corresponding to the clinically suspicious symptoms was found. Conclusion: Pseudo-malignancies are rare and diffi cult to diagnose, even by welltrained teams. The aim of the poster is to propose a review of images of pediatric pseudo-malignancies referred to an oncologic hospital, to make the reader more familiar with those possible problems, allow an easier and faster diagnosis, and avoid unnecessary and sometimes dangerous treatments. Learning Objectives: To provide a free program for handheld devices as a reference database in Pediatric Plain Film Radiography which serves the well and less experienced pediatric radiologist to differentiate between physiological age-specifi c and pathological fi ndings. Background: It is especially diffi cult for the inexperienced radiologist or the resident on-call to differentiate between physiological age-specifi c and pathological fi ndings due to developmental variations in the growing child. The suitable book is often unavailable. To solve this problem, an easy accessible format like handhelds would help in this situation. Procedure Details: Over 450 images in pediatric skeletal radiography can be displayed in radiographic standard settings on a handheld device. All images are categorized by body regions, age and gender. The database can be queried through selection of all three criteria or by choosing each criterion separately. The latter offers itself mostly for determination of bone age using the left hand. Each mode provides the user with at least one reference image according to each body region, age and gender. Conclusion: This program is a free reference database for almost all standard images in plain fi lm radiography, from infancy to adulthood. The database serves the radiologist on-call and the less experienced pediatric radiologist to differentiate between physiological age-specifi c and pathological fi ndings. Learning Objectives: To illustrate the spectrum of ultrasound image fi ndings after wrist and distal forearm trauma in children with no fractures detected on plain fi lms. Background: Wrist and forearm injuries are common in adolescent and become more and more common in younger group of children, mostly due to decreasing age of starting the recreational or professional sport activity. The interpretation of clinical examination in a child is often more challenging than in adults; thus, in the presence of different clinical symptoms (wrist pain, oedema, limited movement) together with normal radiographic examination, the question arises about the nature of the wrist/distal forearm tissue injury. Procedure Details: In 64 children who attended our paediatric admission unit because of wrist/distal forearm trauma and in whom the standard plain fi lms did not reveal any fracture, a wrist ultrasound examination, according to actual ESSR guidelines, was performed. We focused on tendons evaluation (continuity, tears), joint effusion or occult fractures depiction and precise assessment of the extent of soft tissue oedema. We tried to discuss the correlation between the most common ultrasound fi ndings and the patient age, as well as the injury mechanism and clinical symptoms. Conclusion: Wrist ultrasound is a valuable imaging method in children after wrist/distal forearm trauma. It is particularly helpful in cases of an equivocal clinical examination and in the presence of normal radiographic results helps to assess the character of the tissue injury. Learning Objectives: The purpose of this educational exhibit is to emphasise the role of diagnostic and/or therapeutic ultrasonography (US) in diverse congenital and acquired musculoskeletal diseases in children and adolescents. Background: US is a powerful diagnostic tool for the evaluation of musculoskeletal disorders owing to low cost, availability, non-invasiveness, multiplanar capability and real-time studies, which allow dynamic imaging. The absence of ionizing radiation is particularly valuable in children, but experience and proper training is required in the pediatric musculoskeletal pathologies. Procedure Details: A total of 120 patients who underwent sonographic evaluation in our tertiary center during the last 5 years were retrospectively evaluated. US examination was carried out with a Sequoia 512 or an Aspen (Siemens-Acuson), using high resolution technique, dynamic manouvres, contralateral comparison, Color and power Doppler, extended FOV function and interventional procedures.

Other imaging techniques such as MRI, CT or bone scintigraphy were also performed when diagnosis was unconclusive. Congenital (DHD), traumatic, infl ammatory, infectious-toxic (transitory sinovitis, arthritis, pyomyositis, infectious bursitis, cat-scratch disease, subperiosteal abscess, infectious lymphadenitis, osteomyelitis), neoplastic (benign and malignant tumors of bones or soft tissues), foreign bodies, and vascular malformations will be presented with a selection of the most representative cases. Conclusion: US is a rapid, nonionising and very sensitive technique for imaging musculoskeletal disorders in children and adolescents. It also offers the possibility of performing aspiration or biopsy procedures with diagnostic and therapeutic relevance.

Fine-streak artifact quantifi cation and removal in reconstructed CT images O.S. Pianykh, P.M. Boiselle, D. Litmanovich, V. Raptopoulos; Boston, MA/US (opiany@gmail.com)

Purpose: Streak artifacts in CT images can originate from a broad range of factors, and often may be controlled with improved scanning protocol parameters and patient positioning. Therefore, a reliable method is needed to quantify the streak presence in the images, guiding the improvements in the scanning protocols and settings. Streak-quantifi cation methods can also lead to better streak-removal algorithms. Methods and Materials: Fine streaks, typically originating from the noise and photon starvation, can still be detected numerically in reconstructed CT images.

Our approach is primarily based on exploring streak-shape linearity, leading to the following image processing steps: ;inear image fi ltering to enhance streak-affected pixels; streak-searching methods, locating straight lines of pixels either raised or lowered compared to the surrounding pixel background; weighting detected streak lines proportionally to their length and severity; building streak "signature" of the image, showing streak presence by streak severity. Results: Our method provided high accuracy in locating and measuring streak artifacts. This quantifi cation method naturally extended to a streak-removal algorithm, which would "raise" or "lower" image streak pixels to eliminate the streaks.

The proposed streak quantifi cation and removal algorithm can be successfully used to: (1) quantify fi ne streaks in reconstructed CT data. The quantity of image "streakeness" can then be used to improve image scanning parameters and to achieve higher image quality;

(2) remove streak artifacts from the reconstructed CT images without any need for the raw data (generally unavailable).

Performance characterisitics of Dyna-CT acquired by the threedimensional angiography system with fl at panel detector E. Minota; Kobe/JP (minota@fbri.org)

Purpose: The three-dimensional angiograph equipped with fl at panel detector (FPD) acquires a complete volume set during a single rotation, which can be used to reconstruct tomographic images similar to ordinary CT. We evaluated the performance characteristics of images acquired thus, including image noise, spatial resolution in the axial plane, section sensitivity profi le in z-plane (SSPz), contrast noise ratio (CNR), distortion of an acrylic ball, and clinical images.

We used a biplane C-arm angiograph with 30×40 cm amorphous silicon FPD (AXIOM Artis dBA, Siemens Medical Solutions, Germany). The SSPz and axial spatial resolution were measured with miniature iron balls of 0.18-1.0 mm. The CNR was measured with a phantom containing agar cylinders of various diameter and contrast media density. The distortion was evaluated for an acrylic ball of 1 cm diameter at various distances from the center. Data acquisition times were 5 sec (133 projections), 10 sec (248 projections), and 20 sec (495 projections). Results: The image quality degraded as the object was away from the center or when the data acquisition time was short, probably due to the nature of cone-beam 3D reconstruction and the reduced number of views. Correction fi lters improved the image artifacts. The distortion was considered clinically acceptable.

Although the image quality was lower than the ordinary CT, especially for low-contrast objects, it was considered clinically useful if appropriate data acquisition protocol and fi lters were used. This system is very valuable not only for brain angiography, but also for orthopedics and other fi elds where tomographic images are helpful.

Variation of the optimal reconstruction phase for cardiac CT imaging: Analysis by a rawdata-based kymogram approach D. Ertel, T. Pfl ederer, S. Achenbach, M. Kachelrieß, W.A. Kalender; Erlangen/ DE (dirk.ertel@imp.uni-erlangen.de) Purpose: To analyze the dependence of the optimal reconstruction phase for cardiac CT imaging on the patient's heart rate by using a rawdata-based approach and to prove a patient-specifi c dependence.

The rawdata-based synchronization signal (kymogram) is generated by a center-of-mass tracking [Med.Phys., 29 (7)] and provides directly a motion function of the heart. We identify the phase in the cardiac cycle with the lowest variation of the center-of-mass as representing the phase with the lowest velocity of the heart, assuming to be the optimal reconstruction phase for providing motion-free images. Rawdata of 50 patients were used, scanned with a standard cardiac protocol, 64 slices of 0.6 mm, 0.33 s rotation time and concurrent ECG recording (Sensation 64, Siemens, Forchheim). We correlated the identifi ed optimal reconstruction phase derived from our approach with the patient's heart rate to analyze the dependence of the optimal reconstruction phase on the heart rate.

The probability to obtain the best achievable image quality in the systolic phase instead of the diastolic phase increased from 0% to 30% with increasing heart rate. However, individual analysis showed that the optimal reconstruction phase is more patient-specifi c than dependent on the heart rate. Also, the optimal reconstruction phase in the diastolic phase shows a high variation of 20% over all patients. Conclusion: A high patient-specifi c dependence of the optimal reconstruction phase for cardiac imaging was shown. Only a slight correlation with the heart rate was observed. Algorithms detecting the optimal reconstruction phase seem to be promising and essential.

CT scan protocol optimization by the study of focal spot size infl uence on image quality W. Qi, X. Du, J. Li, S. Zhang; Beijing/ CN (jianying.li@med.ge.com) Purpose: To optimize CT scan protocols in various applications by analyzing the infl uence of focal spot size on image quality. Methods and Materials: A Catphan500 CT phantom was scanned with large and small focal spots with the same dose by adjusting scan time. Images were reconstructed using both standard and bone-plus kernels. Modulation transfer function (MTF) and slice sensitivity profi le (SSP) were used to evaluate in-plane and Z-axis resolutions, respectively. Two radiologists evaluated and scored inner-ear images of 15 volunteers with large and small spots without knowing the scan techniques.

The MTF values and FWHM values of SSP with small spots were always 5-10% better than those of large spots. With standard algorithm, the 10% MTF values were 6.94 LP/cm and 7.45 LP/cm for the large and small focal spots, respectively. For patient inner-ear images reconstructed with bone-plus kernel and 10 cm DFOV, small spots outperformed large spots by 29 to 1. However, the visual advantage of using small spots decreased when the images were reconstructed by standard kernel and 25 cm DFOV.

The use of small spots improved both in-plane and Z-axis spatial resolutions by 5-10% compared to large spots. The improved resolution translated into clinical diagnostic advantage for small DFOV, high-resolution applications. However, this advantage decreased when large DFOV and standard reconstruction algorithm were used, which suggested that one could have balanced usage of focal spots in these applications.

Image reconstruction using a combined algorithm for a translating and rotating volume CT ( Purpose: We describe a new system, TRVCT (Translating and Rotating Volume Computed Tomography), developed for a computed tomography image of a large object. It is a simple method and offers a low price. The key point of this new method is that it handles the movement of an object that is translating and rotating simultaneously. Methods and Materials: Using a vertical linear array detector, one tomogram image can be acquired when the object is translating and rotating simultaneously. This method is completely different from that of a normal X-ray CT. We used a fan-beam X-ray. The direction axis for the detector and rotating axis are parallel. Because a hundred or thousand tomograms with Z-axis are from just one scanning, this system has excellent Z-axis resolution and has the advantage that this technique can improve the resolution in the X-Y plane with changing translating speed and frequency of data acquisition. The image reconstruction algorithm is composed of a modifi ed con-beam CT algorithm and parallel beam CT algorithm. 

Radiation dose and risk from fl uoroscopically guided percutaneous transluminal angioplasty and stenting in the abdominal region J. Stratakis, J. Damilakis, D.K. Tsetis, N. Gourtsoyiannis; Iraklion/GR (jstratak@med.uoc.gr) Purpose: To estimate radiation dose and associated risks resulting from fl uoroscopically guided percutaneous transluminal angioplasty and stenting in the abdominal region. Methods and Materials: Examination parameters for renal and aortoiliac procedures were derived using data from 80 consecutive procedures performed in our institute. Organ and effective doses were estimated for endovascular procedures using the Monte Carlo (MC) transport code and an adult mathematical phantom. Thermoluminescent dosimeters were used in an anthropomorphic phantom to verify the MC calculations. Radiation-induced cancer and genetic risks were estimated using appropriate coeffi cients. Results: Results are presented as doses normalized to dose area product, so that the patient dose from any technique and X-ray unit can be easily calculated for iliac and renal PTA/stenting sessions. The average effective dose varied from 15 to 24.5 mSv depending on procedure scheme and the sex of the patient. Differences of up to 17% were observed between MC-calculated data and data derived from thermoluminescent dosimetry. Conclusion: Male patients up to 59 years old are subjected to a signifi cantly fatal cancer risk. Radiation-induced cancer risk may be considerable for younger individuals undergoing transluminal angioplasty with stent placement. 

Application of a radiation therapy planning system for measurement of organ-absorbed doses inside the body during whole-body CT acquisition using homogeneous and heterogeneous phantoms and 30 clinical cases N. Funabashi, T. Fujibuchi, N. Tanabe, M. Uehara, I. Komuro; Chiba/JP (toshifujio@ybb.ne.jp)

Purpose: Absorbed radiation doses on the body surface and inside phantoms can be measured using dosimeters during CT examinations, but measurements inside the body are diffi cult. Therefore, simulation-based methods are often applied to estimate the latter, but this is rather time-consuming. We investigated a new method that uses a radiation therapy planning system (RTPS).

We used tough water and Rando phantoms as homogeneous and heterogeneous phantoms, respectively, and measured absorbed radiation doses by ionization chamber and Photoluminescence Dosimeter (PLD) compared to RTPS estimates. Furthermore, in 30 clinical cases acquired by multislice 120 kV CT (Aquilion, Toshiba), calculated the absorbed dose using an arc beam calculation system. Results: In a homogeneous phantom, the difference between values measured by ionization chamber and those estimated by RTP were 0.13±7.66% at Y axis, -1.09±17.64% at Z axis, and 1.00±3.76% in the total irradiation fi eld. In a heterogeneous phantom, the difference between PLD and RTP values was 4.97±20.48% for the body and -7.05±17.92% for the lung. Conclusion: The RTP system may be a simple and useful tool for estimation of absorbed radiation doses inside the human body even during whole-body CT acquisition. (13) and vascular surgery (4) centres participated in this multi-centre study. Individual extremity doses were monitored per procedure with highly sensitive detectors at fi ve positions: the forehead, both hands and both legs. Doses to up to three staff members (physician, assistant, nurse) were simultaneously measured during a procedure and relevant exposure data (position, patient-DAP-dose, protection) were registered. Results: Data was collected from a total of 280 procedures. The median dose per procedure to the physician's eyes (62 µSv) was signifi cantly lower than the doses to the legs (181 µSv) and hands (193 µSv) as most centres used an under table X-ray tube exposure geometry. A moderate to strong correlation between patient-DAP-dose and dose to the physician was observed. At vascular surgery centres, DAP-normalised staff doses were about three times higher than in angiography centres. In centres with a low workload, elevated normalised doses were observed. Extrapolated data showed that two physicians may likely exceed both annual dose limits of the eyes (150 mSv) and the skin of the legs (500 mSv). About one third of the physicians removed themselves consistently from the patient during image acquisition. This proved to be a very dose effi cient working procedure. Procedure Details: First, CT numbers from CT images were converted into mass density and elemental weights of tissues required as input for dose calculations with GEANT4, which is a toolkit for the simulation of the passage of particles through matter. They were set by x-y coordinate, slice location, and slice thickness. They were exposed to X-ray from the X-ray tube simulator developed by us in GEANT4. The simulator exposes X-ray of any energy spectrum (tube volt: 60 kV-150 kV), any expose fi eld, etc. The absorbed doses at skin and at other organs were calculated. The fusion images of CT dose can be displayed by the viewer developed by us.

The patient's absorbed dose at skin can be found correctly using Monte Carlo algorism without TLDs. Doses at skin and at other organs can both be estimated by the software developed by us. Patients and medical staff can calculate the patient's exposure dose distribution by 2D fusion images of CT dose. 3D fusion images help them for the explanation of side effects from exposure and for obtaining informed consent from patients.

A low-density board placed on the couch reduces a patient's skin doses in interventional procedures A. Kawabe, Y. Nakagiri, Y. Takeda; Okayama-city/JP (akawabe@md.okayama-u.ac.jp) Purpose: In interventional procedures, scattered radiation generated on the interventional couch increases a patient's skin doses. Here, we assumed that this low-energy scattered radiation is removed by air gaps between the couch and patient. However, it is physically impossible to produce air gaps between the couch and patient. To solve this problem, we have devised a new process. This process involves the use of a low-density polystyrene board, which acts as an air-gap substitute. The purpose of this study was to investigate the air-gap-reproducing effect of the low-density polystyrene board.

The entrance skin dose (ESD) was measured without interspaces between the couch and phantom (25 cm acrylic block), which was defi ned as a reference ESD. Low-density polystyrene boards (1 to 10 cm) were inserted between the couch and phantom, and ESDs were measured, respectively. These ESDs were compared with the reference ESD.

The low-density polystyrene boards with a 6 cm thickness, inserted between the couch and phantom, led to an ESD reduction of about 10%. Conclusion: The low-density polystyrene board simulated air gaps. In interventional procedures, these boards can be implemented easily and inexpensively in a clinical setting, resulting in reductions in a patient's skin exposure by as much as 10%, without affecting image quality.

Measurement of occupational exposure in a mobile PET unit M. De Marco, S. Maggi; Ancona/IT (black_dragon@libero.it)

Purpose: The routine handling of unsealed 18 F-FDG in a mobile PET unit, that is usually not provided with a hot cell, may result in the production of airborne radioactivity. The aim of our study was to quantify the occupational radiation exposure for a technologist working in a mobile PET unit, evaluating both internal contamination and external irradiation. Methods and Materials: Internal exposure: each technologist was issued with a Personal Air Sampler that collects the air that the worker is really breathing. External exposure: personal dose equivalent Hp (10) has been quantifi ed using electronic dosimeters. Occupational radiation exposures have been evaluated twice a week for six months based upon an operating PET effi ciency of 9 procedures/day. Learning Objectives: To describe the acceptance of radiation proctection courses for health care professionals in Germany by an anonymous survey. Background: Maintaining safe utilization of ionizing radiation and radiation protection of staff, public and environment requires high levels of competencies. In 2002, the German Radiation Protection and X-ray Ordinance put health care professionals employing ionizing radiation under an obligation to recertify theoretical and practical knowledge. Personnel, i.e. physicians, physicists, radiographers, nurse-practioners and specialist staff, have to enrol for an offi cially approved radiation protection course every 5 years. 8 or 12 hour classes with a multiple choice tests are held by lecturers, radiation protection offi cers and experts in the fi eld. However, a preconceived opinion across all levels of professionalism declares radiation protection education and training redundant and costly. Procedure Details: Course participants were asked to fi ll in an anonymous questionnaire [n=599, radiographers (45%), physicians 44%, including 25% consultants and 10% medical directors]. The survey itemized age, vocational training, professional group, fi eld of practice, course content, stimulus, practicality and course costs. 80% estimated the theory-practice-performance ratio as balanced. Stimulus (great many 20%, many 57%, some 20%). The courses came to participants' expectations (fully 62%, for the most part 33%, partly 4%. Full coverage of the expenses (120-150 Euros) by the employer was reported by 65% of the participants. Conclusion: Although radiation protection is widely considered as a stepchild in health care delivery, professionals are aware of adequate education needs and training.

C 493 B D E F A G

Principles of k-space sampling P. Paolantonio 1 , R. Ferrari 1 , F. Iafrate 1 , M. Rengo 2 , C. De Cecco 1 , A. Laghi 1 ; 1 Latina/IT, 2 Rome/IT (paolantoniopasquale@hotmail.com)

Learning Objectives: To describe principles of k-space sampling. To offer an easy explanation of k-space physics for radiologist. To describe properties of k-space and to illustrate different k-space sampling strategies. To show how different portions of k-space contribute to the fi nal image appearance. To illustrate the rationale for centric, elliptic, spiral and partial k-space sampling strategies. Background: K-space sampling represents a crucial step in MR image acquisition.

The easy way to sample k-space is represented by a sequential mode that is also a time consuming procedure. K-space sampling strategy may be modifi ed in order to reduce acquisition time. A central or elliptic sampling of k-space is recommended for contrast-enhanced-MR-angiography in order to collect central line of k-space during the peak of vessel enhancement. Procedure Details: We show in a step by step form the image generation process focusing our attention on k-space sampling. We will describe how k-space is sampled in several pulse sequences commercially available.

Using graphic examples, we will describe different k-space sampling strategies.

The knowledge of k-space sampling strategies is crucial for understanding MR image acquisition process. Several k-space sampling strategies are available. Using the appropriate k-space sampling strategy is useful in reducing acquisition times and in order to optimise image acquisition for the clinical purpose of MR-studies like happens in centric or elliptic sampling of k-space and contrastenhanced MR-angiography. Background: An increased risk for MRI-associated skin burns has been described for pictorial tattoos using iron coloured pigments. Not until recently, permanent Make-up, a new and rapidly spreading cosmetic technique, has been recognized for putting the patients at risk of burns by MR imaging. Procedure Details: Neither iron pigments nor larger tattoo areas are required to induce burns in these patients. To gain a special colour effect cosmetic tattoos contain metals such as iron, copper and zinc. Locally, electric current can be induced by any of these metals in a high-frequency magnetic fi eld, even if only subtle eye lining has been performed. This mechanism of locally induced electric current is responsible for possible dysesthesia and burns in patient's skin containing a cosmetic tattoo, e.g. permanent make-up during MRI examination. A clinical example, review of the literature and recommendations for addressing this problem in the daily MR practice will be given. Conclusion: Permanent Make-up, for medical purposes better adressed as cosmetic tattoo, can cause severe local damage to the skin during MRI studies even if it is free of iron oxides. Every MR radiologist should be aware of these risks and direct patient's management and staff training accordingly. combining a body coil for radio frequency transmission and an endorectal coil to receive signal. Three-dimensional MRI and MRSI data were collected with magnetic fi eld homogeneity in the selected volume obtained by shimming water with lipid suppression accomplished with selective inversion of lipid resonances. Peripheral voxels were saturated to suppress periprostatic fat and air. We will review how data is then processed and how to interpret a prostate spectrum. Conclusion: In summary, this poster serves to demonstrate the technical aspects of 3D MRSI including practical aspects of implementation and technical considerations. Hopefully, radiologists will understand the basic principles of prostate MRS imaging, and by realising the feasibility and clinical possibility of providing MRSI will be encouraged to initiate prostate spectroscopy. Conclusion: Understanding the magnetic resonance imaging susceptibility effects and their infl uence on imaging appearance allows the clinical radiologist to make a wise selection among the broad range of imaging sequences available to minimize artefacts, enhance pathology detection as well as limit the differential diagnosis.

Liver imaging at 3.0 T: Potential of diffusion-weighted black-blood echoplanar-imaging sequences for large-coverage volumetric imaging I.C. Van Purpose: To evaluate breath-hold diffusion-weighted black-blood echo-planarimaging (BBEPI) as potential alternative for SAR-intensive spin-echo sequences for liver imaging at 3.0 T. Methods and Materials: After institutional review board approval and informed consent were obtained, 14 healthy volunteers were scanned at 3.0 T, using an ASSET compatible 8-channel cardiac coil. Parameters were set to cover the entire liver (25 cm z-axis) in one 25-sec breath-hold, and were varied interactively with regard to TE, TR, diffusion b-value, slice thickness and voxel size. Images were evaluated and compared to fat-suppressed T2w fast-spin-echo (FS-T2w-FSE) for image quality, liver delineation, blurring, geometric distortions, fat-suppression, suppression of the blood signal, CNR and SNR. Results: The optimized short-(25 ms) and long-echo (80 ms) BBEPI provided 2 mm and 4 mm slice thickness with full anatomic, single breath-hold liver coverage (100 and 50 slices, respectively), resulting in voxel size 3.1x2.6x2.0 mm 3 and 3.1x2.6x4.0 mm 3 . TR was 6600 ms. B-values > 20 s/mm 2 showed better suppressed blood signal, but b=10 s/mm 2 provided improved volume coverage and signal consistency. Compared to FS-T2w-FSE, BBEPI provided: (1) comparable image quality, liver delineation and blurring; (2) acceptable geometric distortions;

(3) improved suppression of fat-and blood-signal (p < 0.05); and (4) higher CNR and SNR (p < 0.05). Conclusion: Our study shows that BBEPI can be used for ultrafast, low SAR, thin-slice morphologic imaging of the entire liver in a single breath-hold at 3.0 T, providing near-isotropic data with multiplanar reformatting capability.

Flair 

Absolute Purpose: To estimate absolute concentrations from MR spectroscopic measurements reference concentrations are required. Commonly, either tissue water concentration or separate phantom solutions with known concentration are used. The purpose of the study was to acquire brain spectra in volunteers and to compare the variability of both methods.

Overall twelve volunteers were investigated by 1 H-2D-CSI (STEAM; TE=20 ms, TR=5000 ms) on a 1.5 T whole-body scanner (Magnetom Sonata, Siemens) using the standard head coil. For three volunteers measurements were performed twice with identical sequence parameters except for the water suppression pulse which was switched on only during the fi rst measurement. Spectra were evaluated by the LCmodel. Results: Comparison of absolute concentrations of the metabolites NAA, Cho and Cr obtained with both methods showed stronger differences for voxels located in border areas of the selected volume. The differences between concentrations estimated by using NAA and water as a reference were clearly more pronounced in the parietal region (NAA: 5.4 vs. 7.0 mmol/L; Cr: 3.2 vs. 5.4 mmol/L; Cho1: 0.7 vs. 1.4 mmol/L) compared to the frontal region (NAA: 6.4 vs. 7.2 mmol/L; Cr: 3.9 vs. 4.6 mmol/L; Cho: 1.1 vs. 1.2 mmol/L). This refl ects the spatial variations of the coil sensitivity. Conclusion: As technical parameters like coil-sensitivity and load-factor affect measurements with and without water suppression in the same way, corresponding errors in the estimated absolute intensities can be avoided. Therefore, if time allows an internal reference should be preferred compared to estimation by a reference solution without correction of the sensitivity profi le of the coil. 

Assessment of a fast, 3D MRI pulse sequence for use in polymer gel dosimetry I. Seimenis 1 , P. Baras 2 , P. Papagiannis 2 , P. Karaiskos 2 , A. Angelopoulos 2 , P. Sandilos 2 , L. Vlachos 2 , B. Pantelis 2 ; 1 Nicosia/CY, 2 Athens/GR (yseimen@phys.uoa.gr)

Purpose: The use of MRI as a readout method for polymer gel dosimetry commonly involves long imaging sessions and, therefore, the technique has not been yet established in the clinical setting. This work evaluates the effi ciency and accuracy of a fast, 3D, dual-echo, k-space segmented Turbo Spin Echo (TSE) imaging pulse sequence. Methods and Materials: PABIG polymer gel dosimeters were irradiated with an 192 Ir High Dose Rate brachytherapy source, the 4 mm and 8 mm collimator helmets of a gamma knife unit and a custom made x-knife collimator of 1 cm diameter. Profi le and dose distribution measurements derived from TSE data were benchmarked against corresponding fi ndings obtained with the commonly used and optimised Carr-Purcell-Meiboom-Gill (CPMG) multi-echo CPMG sequence, as well as treatment planning calculations, Monte Carlo simulations, and fi lm and Pinpoint ion ionization chamber measurements. Results: The TSE sequence was found to provide dosimetric results of comparable accuracy with those obtained from CPMG multi-echo acquisitions (within one pixel in the MRI gel readout session, i.e. < 1 mm), and to accurately predict treatments planning calculations and conventional dosimeter measurements in a range of radiotherapy applications that involve very steep dose gradients and stringent dose delivery requirements and which require high spatial resolution in all three dimensions. Conclusion: The signifi cant scan time reduction (64-fold) achieved with the proposed imaging sequence implies that the polymer gel-MRI readout method could prove to be a useful and practical tool in modern clinical radiation therapy applications involving high doses and steep dose gradients. 

Scientific and Educational Exhibits

Procedure Details: We analysed with high resolution skin disorders in all cases. Dermis and subcutaneous fat, and epidermis in such cases, changes were studied. MRI gave useful informations about thickness, localization, signal changes, extension and relationship with surrounding structures of the lesions. In such cases, as phototherapy of sclerodermia, MRI allowed evaluation of the effects of therapy. We obtained substantial informations for differential diagnosis in infl ammatory skin disorders. Conclusion: MR imaging provides global analysis with high resolution of the various skin layers down to the hypodermis and the muscular facia. Characterization of lesions and evolution with treatment are permitted. Skin tumoral lesions are well analysed, MRI is useful to reduce the number of skin biopsies on certain indications.

"Glare" LCD panel improves resolution performance of softcopy display for digital mammography T. Yoneda, N. Hashimoto; Hakusan, Ishikawa/JP (yoneda@nanao.co.jp)

Learning Objectives: To improve understanding of the following points about monochrome LCD monitors which have been getting more popular for digital mammography: 1. Surface coating of LCD panel can affect resolution performance of softcopy display. 2. "Glare" panel has better resolution performance than "Anti-Glare" panel which is currently used for the majority of medical LCD monitors. Background: As digital mammography has been getting more popular, monochrome LCD monitors have also been spreading among radiologists. However, higher resolution and contrast performances are required in order to achieve the accurate diagnosis of mammograms, for example detecting microcalcifi cations. We have developed new 5M-pixel monochrome LCD monitor with "Glare" panel which improves resolution performance. Imaging Findings: Established "Anti-Glare" panel has waffl ed surface to diffuse the refl ection of ambient light. But it also diffuses the light from the monitor's backlight. As a result, the displayed image is blurred especially on outlines compared to the original image. On the other hand, "Glare" panel has fl at surface so that there is no blur with the displayed image. It means that there is no degradation of resolution performance with surface coating. Conclusion: Resolution performances of both panels were compared by measuring MTF (Modulation Transfer Function). "Glare" panel showed higher MTF than "Anti-Glare" panel, which proves the higher resolution performance of "Glare" panel.

Of course, the ambient light in reading room has to be controlled to decrease the specular refl ection, but this higher resolution performance can contribute to the accurate diagnosis of mammograms. Purpose: DNA double-strand breaks (DSBs) are among the most signifi cant genetic lesions introduced by ionising radiation. During angiography, patients are exposed to X-rays for a long time with changing tube position, pulsing rate and fi eld of view. The biological effect of ionising radiation was examined in patients undergoing angiography using a method which was previously applied only in vitro and in computed tomography. Methods and Materials: Individual DSBs were visualised by using immuno fl uorescence microscopy. The method is based on the phosphorylation of the histone H2 AX after formation of DSBs. Blood was taken from twelve patients undergoing different angiographic procedures before, during and after the examination. Additional in vitro irradiation of blood samples was performed (50 mGy) to evaluate the individual repair capacity.

The dose area product (DAP) ranged from 769 to 17587 microGy*m 2 , fl uoroscopy time ranged from 1:20 to 35:09 minutes. In all patients, the irradiation increased the number of DSBs. Maximum of DSBs was found 15 minutes after the end of fl uoroscopy and ranged from 0.03 to 1.36 foci/cell. The number of DSBs showed a linear correlation to DAP and fl uoroscopy time (R 2 =0.87 and R 2 =0.96, respectively). Most of DSBs were repaired within 5 hours in vitro and in vivo. Conclusion: Gamma-H2 AX immuno fl uorescence microscopy is a reliable method to measure the induction and repair of DNA damages caused by ionising radiation during angiography even if very small doses were applied.

Needle-based versus conventional storage-phosphor radiography in paediatric radiology J.M. Fernandez, E. Vano, C. Prieto, J.M. Ordiales; Madrid/ES (eliseov@med.ucm.es) Purpose: To compare exposure requirements for similar image quality with needle-based and conventional computed radiography (CR) systems in paediatric radiography. Methods and Materials: Image quality has been evaluated for both CR systems with a contrast-detail test object covered with varying thicknesses of acrylic to simulate clinical conditions. Four series of images were obtained with two thick-496 B D E F A G nesses: 10 and 20 cm, and increasing tube voltages (60, 81, 102 and 125 kVp). Images were acquired at 7 exposure levels. An image evaluation software was used to determine the threshold contrast of 15 circular holes with diameters ranging from 0.3 to 8.0 mm. Statistical signifi cance of differences between the two digital systems was assessed. Phantom and detector surface air kerma were measured, and correlated with CR exposure levels.

Results: A linear relationship was found between the number of detected holes and the logarithm of exposure. On average, the structured phosphor system required 55% less phantom entrance air kerma than the conventional phosphor plate. Differences in exposure requirements were smaller with decreasing thicknesses of simulated tissue thickness and lower tube voltages (74% at 20 cm and 102 kVp, and 36% at 10 cm and 60 kVp). All differences were statistically signifi cant. Conclusion: Structured CR provides improved low contrast detectability and a potential for dose reduction compared with conventional CR. The best performance was achieved with conditions comparable to those for adult radiography (102 kVp and 20 cm of PMMA). Learning Objectives: To provide insight into current practices of clinical applications of Multi-slice Computed Tomography (MSCT) using the new generation of CT systems able to acquire simultaneously at least 16 sections, and to identify specifi c applications that justify the radiation exposure. Background: Rapid technical developments in CT have had a substantial impact on the applications of this technology. Since CT is already associated with a relatively high (collective) patient dose, a review of current practices was performed. Procedure Details: Administrative patient data on diagnostic applications corresponding to one contiguous year, and CT reports corresponding to 10% of the annual data have been retrieved from the information systems and referral forms of six radiology departments in different European countries. Data pre-processing included coding the medical specialties, the age groups, anatomic regions, and most important coding of the diagnoses from medical details mentioned in the reports. The resulting database includes 70041 CT examinations, of which 54127 were referred by medical specialties concerning 33149 patients. To learn from these data, descriptive analyses have been performed. Conclusion: CT examinations are predominantly performed on patients in the mid-and higher age categories. The highest referrals are by oncology; followed by surgery, internal medicine, neurology and neurosurgery. A substantial number of patients received more than 6 CT examinations in 1-year, mostly for oncology. Most frequent diagnostic categories are neoplasms; followed by diseases of the musculoskeletal system, vascular system, respiratory system, digestive system, urinary tract, and nervous system.

MTF and NPS measurements including X-ray scatter -application in a digital mammography system H. Perez-Ponce 1 , P. Monnin 2 , F.R. Verdun 2 , A. Noel 1 ; 1 Vandoeuvre-lès-Nancy/FR, 2 Lausanne/CH (hpponce@softhome.net)

Purpose: Detector characterization with modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum effi ciency (DQE) inadequately predicts image quality when the imaging system includes patient scatter. This contribution investigates the effect of X-ray scatter on the MTF and NPS in mammography for characterizing the system in clinical situations.

A full-fi eld digital mammography unit was characterized at 28 kV Mo/Mo at two beam qualities with and without X-ray scatter. Pre-sampling MTF and NPS without scatter were measured according to the IEC 62220-2 standard. The same imaging parameters were measured again with a mammography test object that simulates X-ray scatter due to the breast. Results: X-ray scatter causes a falloff of MTF [6% at very low spatial frequency (0.1 mm-1) and 9.5% for the rest of the spectra] and adds a constant amount of noise (3% from 0.5 to 2 pl/mm, 6% from 2.5 to 4 pl/mm and 8% from 4.5 pl/mm to the Nyquist frequency). This increase in image noise is related to the amount of scatter integrated by the detector. The reduction of MTF and the increment of noise implies the drop of the DQE at all frequencies.

The properties of an image receptor are properly characterized with a scatter-free beam. In clinical situations, detectors are used with X-ray scatter from the patient. The use of a test object including scatter to measure MTF and NPS describes the resolution and noise properties of the imaging system with regard to scatter from the patient.

The impact of Nikola Tesla on X-rays discovery M. Hrabak, R. Stern Padovan, M. Prutki, K. Potocki; Zagreb/HR (maja.hrabak@zg.t-com.hr) Learning Objectives: To present the role of Nikola Tesla's (1856 Tesla's ( -1943 research in X-rays discovery and invention of modern imaging technologies. Background: Discoveries of Nikola Tesla represent basics of traditional, but also modern imaging techniques. Tesla's work is present in every radiological department, including fl uorescent lights in viewboxes, alternating current (AC) supplying the equipment, Tesla-Knott generator used for X-ray equipment, etc. One of Tesla's never completed work was experiments with what would later be called X-rays. Procedure Details: Tesla's articles published on the topic of X-rays and their biological hazards in The New York Electrical Review in the years 1896 and 1897, Tesla's biography, as well as medical papers mentioning Nikola Tesla were analyzed. Conclusion: Since April 1887, Tesla began investigations using Crookes tubes, and his own vacuum tube which was a special single-electrode X-ray tube without target electrode. It seems that by 1892, he became aware of what Roentgen identifi ed as X-rays effects three years later. He didn't publicly declare his fi ndings nor make them widely known, and much of his research was lost in a fi re in his laboratory in New York in 1895. He was also among the fi rst to comment on the biological hazards of working with X-rays with the conclusion that distance was a useful safety factor.

Count-rate analysis in PET with LSO detectors F. Bonutti, R. Padovani, O. Geatti; Udine/IT (bonutti.faustino@aoud.sanita.fvg.it)

Purpose: The optimisation of the acquisition parameters in PET has the purpose to improve the quality of the diagnostic images. Optimisation can be done by maximizing the NECR that in turn depends on the coincidences rate. Methods and Materials: For each bed, the scanner (Biograph Duo, Siemens) records the coincidences and the singles rates in a log-fi le. For each patient, we fi gure out the functions Trues=T (s), Randoms=R (s), Scatters=S (s) (where s = single count rates) by fi tting the NEMA 70 cm phantom count rate curves on the measured clinical points, in order to analytically calculate the personalized PseudoNECR (s) curve linked to the NECR curve. Results: For central beds, we estimate a missing activity of ~70% to get the PNECR_max, but the improvement in terms of SNR that we could get is around 15%. We also estimated the correlation between the patient weight and the PNECR_max, in order to fi gure out which should be the scan duration of a single bed in function of the patient weight to acquire the same PNEC. If we normalize the counts at the PNECR_max for the 70 Kg patient, the bed duration for a 90 kg patient should be 230s, which is ~30 % longer. Conclusion: Although the analysis indicates that the fast electronics implemented in the scanner allows the use of higher administered activities, we found that this would involve a poor improvement in terms of NECR. The attention can be instead addressed on the usefulness of higher bed duration for heavier patients.

Radiology Learning Objectives: To describe our experience in development of 'joint ventures' between a Radiology Department and a Basic Research Physics department. To analyze pros and cons of this collaboration from little initial projects to participation in large EU projects. Background: Clinical Radiologic departments and basic research Physics groups live frequently far away in work and mind from each other. However, to create a collaboration group between a Radiology department and a Basic Physics research group provides great benefi ts for both institutions. Procedure Details: We describe our experience, projects and lessons learned about how to begin a 'joint venture'. We analyze possible benefi ts for a Radiology Department from a Physics group including: a) experience from informatics management providing different solutions for several problems of our departe-C 497 B D E F A G ment: advice for PACS and workfl ow, creation of an online database of radiologic cases, teleradiology; b) experience with management of european public money sources of money; c) performing basic research: in our case, with CAD. Possible benefi ts for a Physics group from a Radiology group: a) lessons from a different point of view b) application of basic research developed in practical applications more easy for marketing in the EU. In addition, basic research scientists have frequently a sensation of null practical application of their work, just the opposite of our daily clinical work. Conclusion: Creation of joint ventures between basic Physics research groups and Clinical radiologic departments can provide great benefi ts for both groups in scientifi c, economic and open-mind views.

Comparative evaluation of LCD with anti-glare panel and glare panel for digital mammography K. Oda 1 , M. Sawada 1 , A. Ishikawa 1 , H. Imai 1 , K. Ichikawa 2 ; 1 Anjo, Aichi/JP, 2 Nagoya, Aichi/JP (oda@kosei.anjo.aichi.jp)

Purpose: Many current LCDs use anti-glare panels, which have a waffl ed surface to diffuse the refl ection of ambient light. However, this also diffuses the light from the LCD's backlight. The aim of this study was to compare the spatial resolution (modulation transfer function: MTF) and the noise (noise power spectrum: NPS) of high-resolution LCDs with anti-glare and glare panel for digital mammography. Methods and Materials: 21" LCDs (2560 x 2048) with a anti-glare panel and a glare panel were evaluated. A uniform image and a bar-pattern image displayed on an LCD were measured with a high-resolution single-lens refl ex type digital camera (D70, Nikon) equipped with a close-up lens. In order to avoid signifi cant errors caused by periodic components of the pixel structures, noise profi le data was processed by the hanning window.

The LCD with a glare panel had better MTF characteristics and displays a sharper image outline. Furthermore, the LCD with a glare panel had better NPS characteristics than the LCD with an anti-glare panel.

The LCD with a glare panel was excellent in physical characteristics by comparison with the LCD with an anti-glare panel for digital mammography. The glare panel was effective in a dark environment with no refl ections of surrounding light.

Visualization Purpose: In certain cases, a coloration occurs under ultrasound investigation with color Doppler, which is regarded as an artifact of a pseudo-fl ow. A fi ne-dispersive suspension moving in the direction opposite from the probe can be seen. The reasons and properties behind this phenomenon require further investigation.

The experimental research was carried out. The highfrequency probe was submerged into a container fi lled with a suspension of talc in degassed water, and ultrasound scanning was performed. Results: In the B-mode, displacement of talc elements to a direction opposite from the probe was visualized. In the color Doppler mode with low PRF values, this displacement was registered as coloration corresponding to movement from the probe. Increase in intensity of the displacement was marked under the following conditions: Focus shift to distant zones; implementation of Doppler modes, especially power mode; increase of Doppler frequencies. Reduction of movement intensity was registered in the following cases: Reduction of acoustic power level (at 40% quite stopped), increase of liquid viscosity (the suspension of talc in glycerin practically did not move). Conclusion: Visualization of streams in liquid accumulations is a refl ection of real liquid untwist, which can be explained by the well-known physical phenomenon -acoustic current. Correct understanding of this occurrence enables us to interpret some phenomena that are found in pathological cystic formations.

Evaluation of patient entrance skin dose with an online measurement system in interventional neuroradiology Y. Takei 

The ESD were different among interventional procedures greatly. The ESD was fi ve times greater with TAE than with TAI procedure. In 4 patients with TAE, the ESD exceeded 2 Gy, and they underwent transient loss of hair. The ESD in TAE for vascular diseases counted higher than in other procedures. It could be due to the fact that fl uoroscopy and angiography were performed more to understand the complex vascular structure such as arterovenus malformation (AVM). Conclusion: Simultaneous ESD monitoring was useful as an alarm so that doctors can reconsider their treatment strategy on the spot and radiological technologists the X-ray tube load to reduce the total patient dose.

Dose-reduction experiment during a cervical vertebrae examination R. Pedersen, O. Muharemovic, M. Nielsen; Copenhagen/DK (radiograf@privat.dk)

Purpose: The purpose of this experiment is to examine the possibility of dose reduction during a cervical vertebrae examination by adjusting predetermined parameters, and still maintaining acceptable image quality. Methods and Materials: Data collected from 21 Danish X-ray departments show a wide variation in parameter settings prior to a cervical examination. To assess the absorbed dose in the thyroid gland, TLD (tablet lithium fl uoride) are used. The tablets are placed in the area of the phantom, which corresponds to the thyroid gland´s anatomical position. Image quality is assessed using images of a specially designed plexiglass phantom, which is equivalent to a human phantom in density and overall composition. The plexiglass phantom has a built-in linear phantom and density holes that enable one to measure and assess the contrast in the images. Results: Signifi cant dose reduction was achieved by using PA instead of AP exposure, resulting in minimal image quality deterioration. By using AEC in AP, PA exposure with 66 kV, one can reduce the dose signifi cantly. The best image quality is achieved under AP/PA exposure using grid ratio 12:1. However, with the ratio 8:1, we were able to observe a signifi cant dose reduction of up to 74%, but at the same time there was a slight deterioration of image quality. Conclusion: This experiment shows that with a certain predetermined parameter regulation, a signifi cant dose reduction of 60-74 % is achieved in the thyroid gland. At the same time, a slight image resolution reduction is observed that does not affect the diagnostic quality of the image.

Increased aluminium fi ltration as a dose reducing tool in AP and lateral lumbar spine images of a phantom E. Kelliher, C. D'Helft, J. Thompson, P. Brennan; Dublin/IE Purpose: The CEC guidelines (1996) recommend a minimum total fi ltration level of 3.0 mm aluminium equivalent for lumbar spine radiography. This phantom based study examined the effects of increasing aluminium fi ltration up to 7.0 mm on radiation dose and image quality. Dose optimization is of added importance when lumbar spine radiography is performed on females of childbearing age, due to increased risk of cancer induction in young patients and the risk of irradiating an undiagnosed foetus. Methods and Materials: Serial AP and lateral lumbar spine radiographs were taken of a tissue equivalent phantom, beginning at a total fi ltration level of 2.5 mm, and increasing in increments of 0.5 mm, up to 7.0 mm. Three exposures were taken for each projection at each fi ltration level. TLDs were used to measure entrance surface dose, reproductive organ dose and fetal dose. Image quality assessment was performed using anatomical criteria based analysis. Results: For the AP lumbar spine exposures, the optimal level of total aluminium fi ltration was 6.5 mm. This provided 34%, 18%, 27% and 19% reductions in entrance C 499 B D E F A G of the colon was carried out with two different methods, depending on which part of the intestinal tract was meant to be examined. Method I: To achieve isolated distension of the colon, 5-10 ml of air was infl ated 30-60 times, then about 20 ml of air was pumped 10-15 times. If tension around the coecum was felt, scout view was done. Method II: To achieve distension of the colon and small bowel simultaneously, infl ation was started by pumping 20 ml of air 25-40 times, then about 15-20 ml of air was pumped 10-15 times. With this method, air can pass easily through the Bauchim valve. Results: Distension of the colon was appropriate with both methods. In 140 cases, we wanted to produce isolated colon distension. It was succesful in 127 cases. In 50 cases, we wanted to examine small bowel too. It was successful in 47 cases. Conclusion: With these two methods, a higher percentage of cases could be successfully examined. Virtual colonoscopy of the colon and small bowel becomes more effective and the patient's unnecessary feeling of discomfort could be lessened.

Evaluation of optimal cardiac phase determination method using cardiac phase image subtraction in coronary CT studies T. Yamaguchi, N. Honma, K. Satoh, K. Urasawa; Cyuo-ku,Sapporo/JP (yamataka@eagle.ocn.ne.jp)

Learning Objectives: To easily determine the optimal cardiac phases in coronary CT studies. To quantitatively evaluate the "elements of cardiac motion" in each cardiac phase. To compare this optimal cardiac phase determination method against conventional visual evaluation. To automatically determine the optimal cardiac phases. Background: In current coronary CT studies, determining the optimal cardiac phases for depicting the coronary arteries is a time-consuming process that is based on visual evaluation. A quantitative evaluation method is therefore eagerly awaited. Procedure Details: The subjects were 40 patients who underwent cardiac CT studies. Using data acquired by ECG-gated reconstruction, images of cardiac phases in the range from 0% to 99% were generated for three planes near LAD #6 to #7, RCA #1, and RCA #2 using the relative delay method, and subtraction was performed repeatedly for images in consecutive cardiac phases. The in-plane SD values of the subtraction images were measured, and the mean SD value in each cardiac phase was plotted on a graph. The agreement rate between the phase with the minimum SD value and the optimal cardiac phase determined by visual evaluation was 83% within the range of 5% of the cardiac phase. Excluding patients with atrial fi brillation, the agreement rate was 93%.

The optimal cardiac phases for depicting the coronary arteries can be determined with good accuracy using this cardiac phase image subtraction method. Not only can the optimal cardiac phase be determined automatically without visual evaluation, but the time required for coronary CT studies is substantially reduced.

"How to" CT-enteroclysis: A guided step-by-step approach A. La Fata 1 , L. Damiani 1 , E. Maffei 1 , A.A. Palumbo 1 , T.V. Bartolotta 2 , M. Midiri 2 , F. Cademartiri 1 ; 1 Parma/IT, 2 Palermo/IT (lafatalaura@virgilio.it)

Learning Objectives: 1. To describe the various methods of CT-Enteroclysis (CT-E) of the small bowel. 2. To give an overview of the different experiences worldwide (Italy, Germany and American). 3. To compare the different techniques for CT-E describing advantages and pitfalls. 4. To provide a pictorial assay of different diseases as they appear on CT-E. Background: Computed Tomography Enteroclysis (CT-E) is a technique for the assessment of the small bowel. It is performed after small bowel distension by administration of a high volume of contrast medium via a nasojejunal catheter followed by CT acquisition. CT-E combines the inherent advantages of conventional barium enteroclysis (i.e. homogeneous luminal distension resulting from volume challenge) with those of cross-sectional imaging (i.e. simultaneous detection of intraluminal, mural and extraintestinal abnormalities). However, it is a challenging technique with several steps that have to be optimised. Imaging Findings: The main variability observed between different protocols regards the choice contrast medium. German investigators use positive contrast agent (i.e. diluted barium sulphate suspension or water iodinated contrast material), American and Italian investigators use neutral intraluminal contrast agents (i.e. water or 0.5% methylcellulose). Differences are also reported in the choice of nasojejunal catheter (i.e. Maglinte or Rollandi techniques), in the use of sedation and in the preparation of patients. The optimised protocol for each indication will be provided in the exhibit.

CT-E is a novel modality for the assessment of small bowel that may completely vicariate previously used modalities.

Information helpful for students in understanding isotropic resolution K. Tsujioka, Y. Uebayashi, M. Anzui, T. Goto, T. Sekitani, K. Asano; Toyoake-city Aichi/JP (tsujioka@fujita-hu.ac.jp) Learning Objectives: This report illustrates a scanning method used to achieve isotropic resolution and a display method that allows for the effi cient use of isotropic resolution in image diagnosis. Background: Traditionally, we understand that CT scan images come from tomography. However, due to recent developments in helical scanning and multi slice CT technologies, CT scanning equipment has advanced from two-dimensional to three-dimensional data collection, and, similarly, CT images have shifted largely to three-dimensional observation of a section from a two-dimensional one. Isotropic resolution is an essential factor in meeting current needs in CT technology. Isotropic resolution means that the elements composing CT images hold equal, three-dimensional resolutions. Imaging Findings: For evaluating spatial resolution, a micro globe 0.18 mm in diameter made of tungsten was used. For evaluating contrast resolution, we used a dual glove phantom having a small difference in CT value. We also evaluated artifact.

The results of the experiment found that change occurs in the X-Y direction and the Y axis direction depending on how parameters are set for scanning. In the actual clinical environment, we must consider such characteristics for parameter setting and also be aware of the optimization of isotropic resolution for CT image display. As this report serves to provide a description of parameter setting for CT scan, which has grown more complicated in recent years, we fi nd it helpful for students who are unfamiliar with CT operation.

Optimal scanning parameters for CT perfusion in patients with esophageal cancer H. Sato, N. Yanagawa, K. Syutou, T. Kazama, K. Fukuchi, S. Okazumi, T. Ochiai; Chiba/JP (hirotaka-sato0908@excite.co.jp)

Purpose: To determine optimal scanning parameters for CT perfusion in patients with cancer of the esophagus. Methods and Materials: Forty-fi ve esophageal cancer patients underwent CT perfusion. Scans were performed using a multi-detector row helical CT. The imageacquisition factors were the following: 4x5 mm collimation, 1.0sec/rotation, 120kv. Forty ml of intravenous contrast was injected at a rate of 5 ml/sec followed by 20 ml saline. The delay between the start of injection and scanning was 5 sec in 33 cases and 10 sec in 14 cases. The tube current was set 40, 60, 80, 100, and 120 mA in esophageal cancer patients. All the data were reconstructed with 2.5 mm, 5 mm, and 10 mm. The shape of time density curve (TDC) was visually evaluated and the association of prognosis and blood fl ow was evaluated. Results: The prognosis and blood fl ow was best correlated when the slice thickness was 5 mm. The shape of TDC was bad scanned at 60 mAs in esophageal cancer patients. In one out of 3 esophageal cancer patients with delay time of 10 seconds, arterial enhancement started before the scanning. Conclusion: In esophageal cancer patients, scan may be obtained at 5 mm-thickness, more than 60 mAs, and delay time of 5 sec.

To determine the optimal SD setting level in abdominal CT examinations N. Yagi 1 , Y. Muramatsu 2 , R. Sekiguchi 2 , H. Sato 1 , S. Tsukagoshi 1 , K. Takahashi 2 , I. Aizawa 2 , K. Yokohama 2 ; 1 Tochugi/JP, 2 Chiba/JP (y_c_h_o_k_u@yahoo.co.jp)

Purpose: In CT-AEC based on image quality (SD) setting, the SD level selected strongly affects the balance between exposure dose and image quality. The purpose of the present study was to determine the optimal SD setting level in abdominal CT examinations. Methods and Materials: Unenhanced and enhanced (arterial-phase and latephase) helical CT images of 24 patients (17 men and 7 women) with hepatocellular carcinoma were acquired for follow-up without CT-AEC. Using this CT raw data, simulated images with 3 different SD levels (SD10, SD12, SD15) with CT-AEC were reconstructed using a computer simulation program (Raw-NASu, Toshiba, Nasu, Japan). The images were reviewed by 5 radiologists who were blinded to the SD levels to evaluate the degree of diagnostic accuracy using the continuous confi dence judgment method (0 to 100). Statistical analysis was conducted for the evaluation values of 3 of the radiologists, which showed normality.

The mean evaluation values ± standard deviation were 44.0±24.8 (n=14) for SD10, 57.1±31.8 (n=15) for SD12, and 33.8±29.0 (n=15) for SD15. ANOVA did not show a signifi cant difference among the 3 groups (p=0.096). However, the paired t-test showed a signifi cant difference between SD12 and SD15 (p=0.045).

Paleoradiology: Methods and possibilities A. Laki 1 , E. Riedl 1 , L.A. Kristóf 2 , I. Szikossy 1 , I. Pap 1 , G. Forrai 1 ; 1 Budapest/HU, 2 Györ/HU Purpose: Radiology is a very useful method in paleopathology, in the diagnosis of pathological changes of ancient human remains. There is not enough reference data about technical parameters of paleoradiological examinations. The aim of our study was to develop and describe the methods of paloradiological examinations and the radiological study of mummies and ancient human bones. Methods and Materials: Sixteen naturally mummifi ed human individuals and 30 bone remains were examined. The bones were at least thousand years old and originated from different places in Hungary. The mummies were discovered in the crypts of Dominican Church, Vác, Hungary, from burials between 1731 and 1841. Conventional radiographs on phosphor plates (at least two views), spiral CT and 1 mm HRCT examinations were performed. From spiral CT data, 3D reconstructions were also made. Results: In the cases of mummies, the conventional radiography parameters had to be reduced by about 75% because of the body's lost water content. Summation was often unavoidable. Obtaining and displaying CT scans also required special settings. The examinations of the bones most frequently revealed traumas and trepanation of the skull. Many degenerative changes of the spine and the joint surfaces were detected. Signs of rheumatoid arthritis, Paget disease, facies leprosa and vertebral tuberculosis could be discovered. In the mummies, vertebral changes, pulmonary tuberculosis, fractures and other traumatic lesions were diagnosed. Conclusion: Radiological examination of ancient bones and mummies can help to diagnose pathological changes in these human remains. New methods for X-ray and CT examinations are necessary due to the special features.

First postgraduate program in medical ultrasound for radiographers in Norway I. Aabel, R. Stokke; Gjøvik/ NO (ingunn.aabel@hig.no) Learning Objectives: Gjøvik University College, in collaboration with Innlandet Hospital Trust, has developed a postgraduate programmeq in medical ultrasound for radiographers in Norway (60 ects). The aim of the course is to educate sonographers with an understanding of the scientifi c principles and the practical applications. Understanding and knowledge of the scientifi c principles will help radiographers in acquiring the skills necessary to apply this knowledge in practice. Clinical competency is an important integral part of the programme. Background: Norway experiences a shortage of radiologists, especially in rural areas. The purpose of this education is to qualify radiographers to perform selected abdominal ultrasound examinations. Procedure Details: This course will be a part time study within 2 years and is organized in 4 modules as follows: Module 1: physics of ultrasound, levels and sophistication of equipment image recording, and artefacts. Module 2: topographic anatomy of abdomen, pathology. Module 3: clinical practice, gained under guidance and supervision of radiologist. Module 4: clinical practice and a written project on a set subject. The course is based on the guidelines developed by the European Federation of Societies for Ultrasound in Medicine and Biology. Structured theoretical and practical training are followed by competency assessment. Conclusion: Through this postgraduate programme in medical ultrasound, Gjøvik University College is the fi rst educational institution in Norway, providing a qualifi cation of radiographers as sonographers.

Clinical science of radiography and radiotherapy: A conceptual analytical study on the research focus of a new academic fi eld S. Sorppanen; Oulu/FI (sanna.sorppanen@oulu.fi )

Purpose: The master's programme in radiography has been running in Finland since 1999, and development of this new academic fi eld has been active. Especially, the relationship with nursing science has been under discussion. This dissertation was purposed to clarify the research focus of this developing academic fi eld, especially in comparison to nursing science.

The study was conducted according to the three-phase hybrid method of concept analysis, combining the theoretical and empirical approach. Concepts of "nursing", "environment", "health" and "human being" were used as the starting point, because they are commonly applied but not clearly defi ned in radiography. Data were collected in forms of literature, expert interviews and written material, and analysed with qualitative content analysis. Results: Concepts defi ning the research focus were found to be "clinical radiography and radiotherapy" (substitute for "nursing"), "environment", "health and illness" (substitute for "health"), and "human being". These concepts were also found to be connected to each other in several ways. Each concept was provided with a theoretical defi nition, and a model was formulated to describe the research focus of this new academic fi eld, which was named as "the clinical science of radiography and radiotherapy". Conclusion: Results suggest that this new academic fi eld may be profi led by a distinctive research focus, diverging from that of nursing science. Results also suggest that this new fi eld must be named as the clinical science of radiography and radiotherapy. Results may be exploited in further academic development, theory development and education within radiography and radiotherapy. B D E F A G

Aortic intramural hematoma: Prognostic CT fi ndings in the acute onset and follow-up C. Sebastia, S. Quiroga, H. Cuellar, A. Miranda, R. Boye, A. Alvarez; Barcelona/ES (mcsebastia@vhebron.net)

Purpose: The aim of this exhibit is to review the CT fi ndings of acute type B aortic intramural hematoma and to assess the prognostic value of these fi ndings.

We evaluated 34 patients with type B (Stanford) aortic intramural hematoma (IMH) by helical CT at the acute onset and yearly thereafter. The series included 33 men and 1 woman, with a mean age of 67 years (range: 49-87). Patients were followed-up for a mean of 5.6 years (range: 2-13 years). The initial aortic diameter (≥40 mm), IMH thickness (≥10 mm) of the affected areas, IMH length, and presence of tiny ulcers at the acute onset were statistically assessed and correlated with poor evolution. Results: Evolution was to healing in 56% of cases and to focal aneurysm formation in 44% of cases. There was no correlation between poor evolution and initial aortic diameter (≥40 mm), IMH thickness (≥10 mm), or IMH length. Ten patients had small ulcers at the acute onset, and there was a correlation between the presence of these ulcers and aneurysm formation. No differences were found in the outcome (healing or aneurysm formation) between the fi rst and the last yearly control.

The only CT fi ndings in the acute onset of aortic IMH with prognostic value were the presence of tiny ulcers in the affected aorta. In addition, the fi rst-year evolution was predictive of the long-term evolution of this entity.

Emergency Learning Objectives: To check CT fi ndings of the most frequent causes of abdominal venous system emergency pathology. Background: Abdominal venous pathology cases presentation, by CT diagnostication, in the radiology department of our hospital in the last two years. Imaging Findings: We show several cases of: abdominal venous system traumatic pathology; aorta-inferior cava vein fi stula, aorta-gonadal vein fi stula; abdominal venous system primary and metastatic disease; septic thrombosis of the splenic vein, porta, superior and inferior mesenteric veins; acute venous thrombosis of a renal graft; thrombosis of the inferior cava vein and renal veins after pregnancy.

The emergency radiologist should consider the abdominal venous system pathology in the differential diagnosis of the acute abdomen in order to achieve a premature diagnostic to reduce morbi-mortality.

Flat-panel CT as a new perinterventional imaging modality in aortic stentgraft procedures: Work in progress E. Rabitsch, H. Illiasch, W. Wandschneider, K.A. Hausegger; Klagenfurt/AT (egonrabitsch@gmx.at)

Learning Objectives: To evaluate the value of fl at-panel CT during aortic stentgraft procedures. Background: Flat-panel CT was performed in 12 patients immediately after endovascular treatment of aortic aneurysms (5 TAA, 7 AAA) on the angiographic table. Images were acquired with a rotating C-arm (Axiom Artis; Siemens), acquisition time was 20 seconds. During a rotation of 200 degree, 538 projections were acquired. Images were displayed in MIP and VRT mode. Eight patients got intraarterial contrast medium (CM). Imaging Findings: In all patients, the entire stentgraft was exactly shown and alignment of the prothesis along the landing zones was well displayed. The aneurismal sack was well shown in 11 patients (1 patient had traumatic rupture). 1 x an endoleak II was detected, 2 x an angiographically verifi ed endoleak I was not detected (1x suboptimal CM timing, 1x no CM administered). Aortic side branches were well shown in all contrast enhanced studies except 1 (suboptimal CM timing). In one patient, distal extension was considered due to suspected short stent-graft at the distal neck. Flat-panel CT showed suffi cient neck coverage and no extension was inserted. Conclusion: Flat-panel CT is a promising imaging tool during stent-graft procedures and may be helpful especially in problematic procedures.

Renal . Isotropic data sets of 0.5 mm slices were available for review and suitable reconstructions using a dedicated graphic workstation (Vitrea 2, Vital Images Inc, USA). Six of these patients were excluded because of aortic stent placement, aortic dissection or surgery, renal atrophy. The fi nal study group for review consisted of 152 patients (97 men, 55 women). Results: Thirty-eight of the 152 patients (25%) had renal artery variants. There were 7 right and 6 left superior polar arteries; 15 right and 6 left inferior polar arteries. 33 accessory renal arteries arose from the aorta, 1 from the right common iliac artery. Six accessory right arteries passed anterior to the inferior vena cava. Two patients had double renal artery, 1 right, 1 left. Two patients had precaval dominant right renal artery. The overall prevalence of precaval arteries was 5%. Conclusion: Renal artery variants are commonly observed during routine MDCT examinations of the abdomen; 64-slice MDCT scanners allow excellent depiction of these variants along all their course, and evaluation of relationships with adjacent structures.

What is the advantage of angio-CT system equipped with 16-channel MDCT? Detection of feeding artery during transcatheter arterial chemoembolisation for hepatocellular carcinomas using 3D-CT angiography generated from the data set of CT hepatic arteriography M. Hirata, T. Kajiwara, T. Tsuda, T. Mochizuki; Toon Ehime/JP (masaaki@m.ehime-u.ac.jp) Learning Objectives: To demonstrate the usefulness of 3D-CT angiography (3D-CTA) reconstructed from thin-slice data set of CT hepatic arteriography (CTHA) obtained from 16-channel angio-CT system for detection of the feeding artery of hepatocellular carcinomas (HCCs) in comparison with digital subtraction angiography (DSA). Background: Selective catheter placement into the feeding artery is important for effective treatment of HCCs and avoidance of hepatic damage after transcatheter arterial chemoembolization (TACE). However, it is sometimes diffi cult to recognize three-dimensional vascular anatomies on two-dimensional DSA alone. 3D-CTA generated from CTHA enables us to identify the exact feeding artery, which is sometimes diffi cult to depict by intravenous CTA, because direct opacifi cation of hepatic artery allows us to produce very precise 3D-CTA. Information of the detailed vascular anatomy and bifurcation point of feeding artery is simultaneously available when we perform TACE. Procedure Details: Patients were injected with 15 mL of nonionic iodinated contrast material at 1.5 mL/sec via a 2.3 or 4 F catheter placed in the common hepatic artery. CTHA was performed at 10 seconds after the start of injection. 3D-CTA was rapidly generated on the imaging workstation equipped for angio-CT system. The vascular anatomies and the target artery for chemoembolization could be recognized easily, especially on the movie display of the 3D-CTA, which gave hints of suitable selection of devices and helped us to make the effi cient strategy for selective TACE. Conclusion: 3D-CTA generated from CTHA is useful for the detection of feeding artery of HCCs during TACE.

Effi ciency of via dorsum pedis 3D-CT venography for varicose veins of lower extremities M. Ishifuro, J. Horiguchi, K. Ito, T. Sueda, K. Sato, M. Kiguchi, T. Furukawa, C. Fujioka; Hiroshima/JP (ishifuro@hiroshima-u.ac.jp) Purpose: The opacifi cation of lower extremities in CT venography (CTV) by intravenous injection of contrast media (CM) via an upper extremity vein is often poor for three-dimensional (3D) display. We assessed whether 3D CTV obtained via dorsum pedis, using the same scanning protocol as for CT arteriography, was useful for understanding the complicated structures of the venous system. Methods and Materials: In 10 cases, diluted CM (6:1 ratio of water and 300 mgI/ mL CM) of a total amount of 140 ml was injected into the dorsum pedis at a rate of 3.5 ml/sec. Scanning was performed from foot to head after a delay of 35 sec.

The total volume of CM was intended to acquire enough enhancement levels in the entire lower extremities. It was tested whether CT values of 500 HU or higher were obtained in the venous systems. Results: Both varicous and deep veins were enhanced over 500 HU in all cases. Superfi cial veins sometimes did not reach 500 HU; however, they were well demonstrated on 3D CT. The 3D CTV helped surgeons in the ligation therapy of the saphenous vein. Conclusion: Three-dimensional CTV via dorsum pedis for lower extremities is a useful tool for the delineation of the venous systems, and helps surgeons as a navigator for ligation therapy.

Effect 

A prospective parallel-group randomized study of the abdominal aorta and splancnic arteries was performed with a MDCT (GE Lightspeed VCT) in 40 patients divided in 4 groups. A non-ionic c.m. was injected with an iodine concentration of 300 mg/ml in group 1-2: (130 ml; injection rate 3 or 4 ml/sec) and of 370 mg/ml in group 3-4 (100 ml; injection rate 3 or 4 ml/sec). Arterial enhancement of the aorta at 3 levels (celiac trunk, SMA, renal arteries) and of iliac arteries was measured, mean values were calculated and statistical signifi cance was assessed. Results: Concentration of 370 mg/ml (injection rate 4 ml/sec) led to a signifi cantly higher enhancement of the aorta in comparison with 300 mg/ml at the level of celiac trunk (329 vs 236, p < 0.01), SMA (325 vs 222 p < 0.01), renal arteries (301 vs 206 p < 0.01) and iliac arteries (169 vs 113 p=0.01; 167 vs 112 p=0.01). 3 ml/sec patients showed a lower enhancement but differences were not statistically signifi cant at the same levels.

Conclusion: An iodine concentration of 370 mg/ml leads to an higher enhancement and better delineation of abdominal aorta and smaller arteries compared to 300 mg/ml. Difference between injection rates of 3 and 4 ml/sec is non statistically signifi cant.

Early postoperative bleeding following living donor liver transplantation: CT fi ndings compared with angiography S. Hong, A. Kim; Seoul/KR (hongses@paran.com)

Purpose: The purpose of this exhibit is to discuss the clinical impacts of early postoperative bleedings after LDLT and CT fi ndings or CT angiographic fi ndings compared with angiography according to the various bleeding causes. Emphasis is laid on evaluation of the possible bleeding arteries according location of hematoma and contrast leakage on CT scan. Methods and Materials: Between March 2000 and Oct 2003, 63 early postoperative bleeding in 50 transplants among 478 adult liver transplants were confi rmed by conventional angiography. All patients underwent twophase multidetector row CT scan before conventional angiography.

The early postoperative bleedings after LDLT were caused by Inferior phrenic artery bleeding (23.8%), jenunal branch bleeding (12.7%), rupture of a hepatic artery pseudoaneurysm (9.5%), right renal capsular artery bleeding (9.5%), intercostal and lateral thoracic artery bleeding after chest tube insertion site (9.5%), Inferior epigastric and superior epigastric artery bleeding (6.3/1.6%), anastomotic site leakage (6.3%), liver surface oozing (4.8%), biopsy site bleeding (4.8%), gastroduodenal and pancreatoduodenal arcades bleeding (1.6%/3.2%), circumfl ex iliac artery (3.2%), and dissection of common hepatic artery (1.6%). Conclusion: Sudden developed hematoma as well as extravasation of contrast material in the same region on CT scan is thought to be predictive CT fi nding of early postoperative bleeding in posttransplant patients. Careful consideration for these fi ndings can prevent the progression into catastrophic status that requires surgical management. B D E F A G aortas and 3 intramural hematomas of the ascending aorta) with a 16-row MSCT unit. In all cases, we performed a retrospective ECG-gated technique, followed by conventional MSCT study of the thoracic aorta. All cases were reconstructed in multiplanar, MIP and VR reformations. Dynamic cine-mode imaging of the aortic valves and thoracic aorta was also done in all cases. Imaging Findings: Images of ascending aorta diseases and postoperative changes are depicted without cardiac motion artifacts; the coronary arteries and their relationship with aortic disease and surgery are assessed. Dynamic studies of the aortic valves and thoracic aorta are presented. Artifacts due to a loss of cardiac synchronization, breath motion and insuffi cient aortic coverage are shown. Conclusion: ECG-gated MSCT allows precise evaluation of diseases and surgery of the ascending aorta and coronary arteries. Dynamic studies allow evaluation of the aortic valve, movement of the intimal fl ap, detection of intimal tears and visualization of patent ductus arteriosus.

Thirty-two-detector row CT angiography of carotid and cerebral arteries: Comparison of 40 ml and 60 ml of contrast material with a bolus chaser H. Shinjyo 1 , N. Takeyama 2 , Y. Ohgiya 1 , Y. Takahashi 2 , M. Obuchi 2 , T. Kitahara 2 , S. Matsui 2 , Y. Kinebuchi 2 , T. Gokan 1 , M. Ishikawa 2 ; 1 Tokyo/JP, 2 Yokohama/JP (momiji@mtc.biglobe.ne.jp)

Purpose: To compare the diagnostic performance of MDCT angiography (CTA) of the brain and neck, using 40 ml and 60 ml of contrast material (CM). Methods and Materials: CTA was performed using 32-MDCT from the aortic arch (AA) to the parietal region. Seventy patients were divided into 2 groups on the basis of CM (300 mg/ml) administration protocol: Group1 (n=35) received 40 ml of CM with 25 ml of saline fl ushing at 4 ml/sec; group 2 (n=35) received 60 ml of CM in the same fashion. First, time to peak enhancement (Ti) of the internal carotid artery (ICA) at circle of Willis (cW) was calculated by test bolus method. Next, scan duration (sd) between AA and cW was calculated (collimation 1.25 mm; pitch 0.969; rotation time 0.4 sec). Scan was started at [(Ti+4)-sd] (sec) in group1, and [(Ti+9)-sd] (sec) in group 2. Thirteen ROIs were placed from AA to above the cW. Mean attenuation of carotid arteries (CaAs) and cerebral arteries (CeAs) were quantitatively analyzed. Venous contamination (VC), and VR and MIP images were also visually analyzed. Results: Although there was a statistically signifi cant difference (p < 0.05) in mean attenuation of each artery between both groups, the attenuation of all arteries in group 1 was over 200 HU, and analysis of VC in group 1 was better than that in group 2. Visual analysis of CaAs showed no difference, and that of CeAs in group 2 was better than group 1. Conclusion: A 40 ml CM CTA of the brain and neck may provide suffi cient attenuation and diagnostic performance.

A vascular tree is known by MDCT before gastrointestinal surgery H. Funatsu, H. Takano; Chiba/JP Learning Objectives: In this exhibit, we illustrate the normal branching pattern of visceral arteries and their variants in the abdomen with use of volume rendering technique. Background: Multidetector-row computed tomography (MDCT) has come to be recognized as a useful diagnostic tool for preoperative evaluation. For example, angiographic images can be easily acquired after administration of IV contrast media. There is a certain kind of vascular variant that can be a potential source of complication during laparoscopic-assisted surgery for its inherent property (e.g. limited view of the fi eld, loss of three-dimensional depth perception, limited surgical manipulation). Therefore, preoperative vascular mapping in each anatomic site would help your colleague. Imaging Findings: Replaced left hepatic artery arising from left gastric artery, common trunk of left gastric artery and common hepatic artery, tortuous course of splenic artery were all depicted and relevant to procedures of or complications after laparoscopic partial gastrectomy. Resection of left gastric artery from which left hepatic artery branches can lead to liver dysfunction. Whether ileocecal artery runs anterior to vein or not determines an approaching method for exposure of superior mesenteric vein during right hemicolectomy. Delineating root of left colic artery would facilitate left colic artery preserving lymph node dissection during laparoscopic low anterior resection. Conclusion: With recent widespread use of laparoscopic procedures, more detailed information about relevant anatomy is required. MDCT providing 3D images could be an imaging method of choice for the purpose.

The effect of cardiac function on aortic peak time and peak enhancement during CT angiography: A retrospective study S. Sakai, T. Okafuji, A. Chishaki, H. Yabuuchi, Y. Matsuo, T. Kamitani, H. Honda; Fukuoka/JP (sakai@shs.kyushu-u.ac.jp) Purpose: To investigate how cardiac function affects the magnitude and timing of aortic contrast enhancement during CT angiography (CTA). Methods and Materials: Twenty-nine patients (21 men, 8 women; mean age: 64.4±13.4 years; mean weight: 59.4±10.3 kg) underwent measurement of cardiac output within 2 weeks of coronary CTA. During coronary CTA, after a test injection, 90 mL of contrast medium was injected at 3 mL/sec and scanning was initiated after a delay based on the previously determined contrast transit time. The cardiac output of each patient was measured by the thermodilution technique, and the cardiac index was calculated. Attenuation of the descending aorta was measured at the workstation every 3 sec with reference to the image acquisition time shown by DICOM header information. Then the aortic peak time and aortic peak enhancement of each patient were calculated. Pearson's correlation coeffi cient analysis was used to investigate the relationships between the cardiac index and aortic peak time or aortic peak enhancement.

The ranges of cardiac index, aortic peak time, and aortic peak enhancement were 1.11 to 5.30 (mean: 3.28±1.08) L/min/m 2 , 25 to 51 (mean: 38.3±7.5) sec, and 273.1 to 598.1 (mean: 390.4±72.1) HU, respectively. With an increase of the cardiac index, the aortic peak time decreased (r=-0.698, p < 0.0001) and aortic peak enhancement also decreased (r=-0.573, p=0.0009). Conclusion: The aortic peak time and peak enhancement during CTA are closely related to cardiac function.

The role of advanced vessel analysis software to evaluate aortic diameter in patients with ascending aorta dilation A. Ferraris, F. Caraffo, M. Oggero, S. Rossetti, A. Secinaro, C. Venturi, M. Martina, G. Gandini; Torino/IT (francesca.caraffo@libero.it) Purpose: To evaluate the "vessel analysis" software accuracy and usefulness versus direct axial slice measurements to estimate preoperative maximum aortic diameter in patients with ascending aorta dilation.

We performed preoperative Angio-CT with 16-row MDCT GE LightSpeed in 39 patients with ascending aorta dilation. Four radiologists with different experience (1-10 yrs) revaluated ascending aorta maximum diameter with "advanced vessel analysis," an automatic system that is able to generate view true oblique cross sectional vascular images perpendicular to the vessel axis, and then evaluated the same patients with simple direct axial measures. Then, we compared the results so obtained to test the interobserver variability with these 2 measurement methods. Results: The mean of the maximum aortic diameters obtained by advanced vessel analysis was 51.19 mm. The mean of the maximum aortic diameters obtained with direct axial measures was 49.68 mm. Interobserver difference was 0.08 mm with the use of "vessel analysis" software and 2.47 mm with direct axial measure. The maximum difference between the 2 radiologists with respect to the direct axial measurements was 21.01 mm, and while using vessel analysis it was 1.12 mm. Conclusion: The routine use of "vessel analysis" software allows minimization of the interobserver bias, and increases the accuracy in the preoperative evaluation of ascending aorta dilatation.

Carotid artery wall thickness and stroke: Evaluation by using multidetector-row CT angiography L. Saba, G. Caddeo, R. Sanfi lippo, R. Montisci, G. Mallarini; Cagliari/IT Purpose: The aim of this work is to determine if carotid artery wall thickness (CAWT) evaluated by using multi-detector-row CT angiography (MDCTA) is an effective parameter to consider as predictive of increased risk of stroke.

In this retrospective study, we analyzed 154 patients by using a multi-detector-row CT scanner. In each patient, we measured CAWT and measurements were made with an internal digital caliper. We divided patients into 2 groups: the fi rst group (group A) included patients without stroke (n = 98) and the second group (group B) included patients with stroke (n = 56), and we made a statistical analysis by using t-student test to asses the CAWT difference in the 2 groups. Results: Measurements of the distal common CAWT varied from 0.1 to 2.2 mm. In group A, average CAWT was 0.8082 mm (0.279 SD) and in group B it was 1.107 mm (0.2 SD). CAWT in group A patients showed statistical difference (p < 0.01) com-C 505 B D E F A G pared to group B. By using 1 mm as the threshold, we observed another statistical correlation (p < 0.0001) for stroke: in fact, patients with ≥ 1 mm CAWT had stroke with an odds ratio 9.8. in comparison with patients with CAWT < 1 mm. Conclusion: Results of our study suggest that an increased CAWT is an indicator for risk stroke and this parameter can be used as risk factors besides other wellknown ones like diabetes, hypertension, smoking, dyslipidemia. Purpose: To prospectively determine the feasibility of two different protocols in patients with peripheral arterial occlusive disease (PAOD) using the current generation of 64-detector row CT scanners. Methods and Materials: Twenty patients with known PAOD underwent 64-CTA (Sensation Cardiac, Siemens). Patients were randomly divided into two different groups (A, B) regardless of age or severity symptoms. Group A was studied using a regular CT scan following the base rule of scan time=contrast material (cm) administration duration; thus, 10 patients received 80 mL of highly iodinated cm (400 mgI/mL) at 4 mL/s; scan time was 20 s and a bolus trigger technique was employed at the level of the proximal abdominal aorta and the acquisition started soon after the attenuation reached 150 HU. Group B received 110 mL of the same cm (independently of scan duration or patient characteristics) with bolus tracking positioned at the level of the infrarenal abdominal aorta; scanning started 13 s after attenuation reached 150 HU. Peripheral arterial tree was divided into 18 segments. Quantitative and qualitative analysis was performed.

Results: In patients with Fontaine II or III, analysis of attenuation values was signifi cantly (p < 0.05) different for the two groups. Higher mean HU values and highest quality images were obtained with group B acquisition strategy. For Group A, attenuation of distal arteries was weak in heavily diseased patients, resulting in poor image quality even for diagnosis. Conclusion: 64-detector row CT angiography allows high spatial resolution angiographic assessment of patients with PAOD; cm administration strategy and scan acquisition protocol require fi ne adaptation to avoid run out the bolus.

Pitfalls in diagnosis of pulmonary embolism with CT angiography E. Protopapa, A. Gyftopoulos, P. Filis; Athens/GR Learning Objectives: 1. To demonstrate the causes of pulmonary embolism (PE) misdiagnosis with the use of CT angiography. 2. To become familiar with a range of pitfalls. 3. To highlight the radiologist's need to determine the quality of a CT pulmonary angiographic study. Background: Computed tomographic pulmonary angiography (CTA) is the modality of choice at our institution for the evaluation of patients with suspected pulmonary embolism because of its high sensitivity. Despite the high accuracy of this method, there are several pitfalls that cause indeterminate CT pulmonary angiography. These pitfalls may be a consequence of patient-related factors such as respiratory motion artifact, image noise and presence of pulmonary artery catheter. Technical factors include mostly inappropriate window settings, partial volume artifact and stair-step artifact. Furthermore, various anatomic and pathologic factors are responsible for the poor quality of the examination. The anatomic factors include partial volume averaging effect in lymph nodes and vascular bifurcation. Finally, coexisting pathology can decrease the value of diagnosis such as mucus plug and tumor emboli. Procedure Details: The patients were examined using 8-detector row CT (GE). The examinations were performed with 4 ml/sec injection rate of 150 ml contrast agent and collimation 16x 0.75 mm with a pitch of 1.2 mm. Conclusion: Although CTA is the standard at many institutions for pulmonary embolism diagnosis, there are several factors that reduce this ability. The radiologist is requested to evaluate the quality of the study and, if it is poor, he should identify which pulmonary vessels are rendered indeterminate and whether additional imaging is necessary.

Factors associated with vessel enhancement in CT pulmonary angiography and indirect CT venography H. Arakawa, T. Kohno, Y. Kaji, T. Hiki; Tochigi/JP (arakawa@dokkyomed.ac.jp)

Purpose: To determine the factors associated with contrast enhancement of pulmonary CT angiography (CTA) and indirect CT venography (CTV). Methods and Materials: 242 patients underwent CTA using bolus-tracking technique, of which 189 patients underwent subsequent CTV. We administered two different amounts of nonionic iodine contrast medium depending on the body weight of the patient: patients with body weight > 50 kg undergoing both CTA and CTV received 450 mg I (group B), while other patients received 300 mg I (group A). The enhancement of vessels was subjectively estimated by the four-point scale and densities were measured at the predetermined levels. Multiple regression analyses were performed with density as the dependent variable, and age, sex, weight, contrast medium, scan delay and presence of embolism as independent variables. Results: The mean scan delay of CTA was 19 seconds (SD: 3.3; range: 10-31). Subjective estimate of enhancement quality in CTA did not differ between the two groups (p = 0.778), while it was signifi cantly better in group B than in group A (p < 0.001) in CTV. Multiple regression analyses revealed that body weight and age were the only signifi cant and consistent independent variables associated with enhancement of the pulmonary arteries. On the other hand, contrast medium, body weight and scan delay were the independent variables consistently associated with the enhancement of deep veins. Conclusion: Bolus-tracking technique showed relatively small variation in the scan delay time. Age, body weight and contrast medium were the important factors associated with vessel enhancement in combined CTA and CTV. Purpose: To evaluate whether low-volume contrast material (CM) MDCT angiography (CTA) utilizing aortofemoral bolus transit time (Taf) can provide suffi cient contrast enhancement. Methods and Materials: CTA was performed using 32-MDCT with 1.25 mm collimation. After surgical bypass graft of abdominal aortic aneurysms, 40 patients were divided into two groups. In group 1 (n=20), Taf was acquired from time to peak aortic enhancement (Ta) at L1 vertebra and time to arterial enhancement at femoral heads by twice-test bolus method. Scan duration was arranged according to individual Taf, and scan delay was 4 sec after Ta. A 40 ml CM (300 mgI/ml) with 25 ml saline fl ush at 4.0 ml/sec was used for CTA. In group 2 (n=20), Ta was calculated only at L1 vertebra. Scan delay was 9 sec after Ta, and table speed was 38 mm/sec. An 80 ml CM was used for CTA in the same fashion. Mean aortofemoral attenuation and mean differentiation between maximum and minimum attenuation were quantitatively analyzed, and also cross-sectional, MIP, and VR images were visually analyzed. Results: Although there was statistically signifi cant difference in mean aortofemoral attenuations (309.4 ± 41.8 HU in group 1 vs. 331.8 ± 64.1 HU in group 2), visual analysis showed no difference between both groups. It is interesting to note that mean differentiation between maximum and minimum attenuation was signifi cantly smaller in group 1 than that in group 2 (26.2 ± 14.1 HU vs. 61.8 ± 45.1 HU, p < 0.01). Conclusion: Low-volume CM CTA can provide suffi cient aortofemoral contrast enhancement.

Visualization of the posterior gastric artery with CT angiography K. Miyatake, K. Nakatani, T. Yamanishi, N. Hamada, T. Okabayashi, Y. Ogawa; Nankoku/JP (jm-kanakana@kochi-u.ac.jp) Purpose: The posterior artery (PGA) is one of the important feeder arteries of the stomach. Although the PGA is unfamiliar with computed tomography (CT) imaging, lymphonode dissection in gastric surgery depends on how the PGA branch and/or run. We evaluated the detectability of the PGA with the 16-scanner multi-detector row CT angiography (CTA). Methods and Materials: A total of 97 preoperative patients [60 men and 37 women, 29-94 years (mean 69.0 years)] underwent CT angiography. The presence and feature of the PGA was assessed by 2 experienced readers using multi-planar reconstruction (MPR).

The PGA was detected in 84 patients (86.6%). In 83 of the 84, the PGA had branched from the splenic artery. In one of the 84, the PGA had branched from the celiac artery. No signifi cant differences were seen between age or sex, and visualization of the PGA. Conclusion: CTA depicts the PGA in a high percentage in this study. Preoperative information of anatomical feature of the PGA can be helpful for planning the surgical strategy. B D E F A G

Intraindividual comparison among source images, MIP and VRI algorithms in Willis' circle anatomy and diseases assessment. Case series and literature review F. Favano, A. Saponaro, L. Fortunelli, F. Travaglini, D. Volpe, A. Stecco, A. Carriero; Novara/IT (chiccait@hotmail.com)

Learning Objectives: To compare the anatomic visualisation and disease assessment of Willis' circle offered by source images (SIs), volume-rendered images (VRIs) and maximum intensity projections (MIPs), and to describe the advantages and disadvantages of each algorithm by means of a case gallery and review of the literature. Background: Although the assessment of source images provides precise local information concerning vessel diameter, source and area, it is often diffi cult to appreciate their spatial relationships and mentally reconstruct their global morphology. MIPs and VRIs are based on post-processing algorithms developed in order to improve the rendering of the overall morphology and/or spatial relationships of anatomic structures, but in addition to their strengths, they have weaknesses that can lead to artefacts and misinterpretations. Procedure Details: MIPs and VRIs are the most widely used means of showing MR angiography data; 3D image displays of vascular anatomy frequently provide excellent information. But both types of reconstruction are associated with disadvantages, such as the misrepresentation of spatial relationships and failure to detect eccentrically located stenoses. A case series is shown to illustrate these aspects. Conclusion: Vessels with low-signal intensities that may be partially or completely imperceptible on post-processing images can be seen on individual source images. In order to improve detection, it is essential to integrate the information coming from SIs, VRIs and MIPs.

Normal The aim of this study is to evaluate the accuracy of MDCTA in the detection of endoleaks aetiology in patients who have undergone endovascular repair (EVAR) of abdominal aortic aneurysm (AAA). Methods and Materials: 212 patients undergone EVAR for AAA. Follow-up was performed using MDCTA after 1, 6 and 12 months after the procedure and every 12 months. 32 patients with endoleaks detected at MDCTA underwent to DSA to determine endoleaks aetiology. The results of the CTA-based endoleak calssifi cation were compared to DSA. Results: Agreement between MDCTA and DSA was observed in 28 patients (87%). In 2 patients MDCTA classifi ed endoleaks as type 2 while DSA as type 1; in 1 patient classifi ed as type 1 at MDCTA, DSA revealed type 2 endoleak; One patient with type 1 endoleak at DSA was incorrectly classifi ed as type 3 at MDCTA.

Conclusion: MDCTA seems to be a feasible technique in the evaluation of endoleaks aetiology. However, selective angiogram with DSA remains the goldstandard to manage endoleaks.

Atherosclerotic carotid plaque quantifi cation with multidetector computed tomography angiography T. Background: Besides carotid stenosis degree, atherosclerotic carotid plaque morphology has shown to be predictive for stroke. Therefore imaging modalities are challenged to provide not only the severity of stenosis but also information on plaque morphology. State-of-the-art multidetector computed tomography angiography (MDCTA) can accurately grade stenosis degree. With a custom made software program, we are now able to assess plaque volume and plaque component volumes. Procedure Details: It will be shown how to perform MDCTA of the carotid arteries with good image quality, low use of contrast material and reduced perivenous artifacts. It will be shown how plaque and plaque component volumes can be assessed. It will be shown how these plaque volumes can be used to assess stroke risk, and what future developments can be awaited.

In vivo assessment of atherosclerotic plaque and plaque component volumes in carotid arteries is feasible. Prospective longitudinal studies which examine the relationship between plaque volume, plaque component volumes, and outcome have the potential to establish MDCTA-based plaque quantifi cation as a stroke risk predictor.

Demonstration The scanning parameters included a detector row confi guration of 16x1.25 mm or 16x5 mm with retroreconstruction of 1.25 mm.

After bolus injection of contrast medial materiel, arterial phase scans were obtained. Multiplanar and curved planar reformation, parallel to the spinal cord, were evaluated and the detectability of the ASA and the AKA were analyzed. Results: The ASA was visualized on the scans of all the patients. The AKA was visualized on the scans of 16 patients (80%), its segmental origin ranged from T8 to T12. 

Analysis of hemodynamics in patient-specifi c stenotic carotid bifurcation using computational fl uid dynamics and MR angiography Y.-J. Xue, P.-Y. Gao, Y. Lin; Beijing/CN (xueyunjing@126.com)

Purpose: To analyze fl ow pattern and hemodynamic variables in stenotic carotid bifurcation in vivo by combining computational fl uid dynamics (CFD) and MR angiography imaging. Methods and Materials: Seven patients with carotid atherosclerosis underwent contrast-enhanced MR angiography of carotid bifurcation by SIEMENS 3.0 T MR scanner. Hemodynamic variables and fl ow patterns of the stenotic carotid bifurcation were calculated and visualized by combining vascular imaging postprocessing and CFD. Results: As the extent of stenosis were commencing and aggravating, the stronger jets formed at the portion of narrowing and more prominent fl ow separation in the ICA with regions of slow retrograde fl uid eddies in the lee of the stenosis. Regions of elevated wall shear stress (WSS) were predicted at the portion of stenosis and at the path of the downstream jet. Areas of low WSS were predicted on the leeward side of the stenosis, corresponding with the location of slowly recirculation turbulent fl ow. Conclusion: CFD combined with MRI can be used to simulate fl ow patterns and calculate hemodynamic variables in the stenotic carotid bifurcation as well as normal carotid bifurcation. The abnormal high WSS may be relative to the rupture of vulnerable plaque. The secondary turbulent, recirculation fl ow associated with low WSS regions on the downward of stenosis are likely to favor plaque development and thrombogenesis.

A protocol for magnetic resonance renal angiography in suspected renovascular disease I. Ahmad, P.S. Lewis, A.H. Choudhri; Stockport/UK (abdul.choudhri@stockport-tr.nwest.nhs.uk) Purpose: Magnetic Resonance Renal Angiography (MRRA) is now thought the best non-invasive technique for assessing Renovascular Disease, with increasing demand putting pressure on our MR service, a limited resource. There being no consensus on indications for MRRA, this study was performed to identify which patients would best benefi t from the procedure. Methods and Materials: Provisional guidelines for requesting MRRA were formulated, including: diastolic BP > 105 at any age; peripheral vascular disease; abdominal bruit; sudden increase in BP; high serum urea and creatinine and/or low serum potassium; BP not adequately controlled despite 3 medications. 100 consecutive patients referred for MRRA were reviewed retrospectively, and the results correlated with the indications and patient management. Renin and aldosterone measurements and renal ultrasound scans were also considered, where available. Results: There was 92% compliance with the provisional guidelines. 92% of studies were diagnostic, 44% being abnormal, with a change in management in 88%. The results correlated well with clinical suspicion and ultrasound fi ndings, but not with serum urea, creatinine or renin measurements. Conclusion: A written referral protocol for MRRA can achieve good compliance and best use of a limited resource, reducing unnecessary requests and aiding non-specialists in selecting appropriate patients. These indications are proposed: i. high BP and age < 40 and ii. high BP and/or chronic renal failure (CRF) with any of the following: audible vascular bruit; > 1.5 cm difference in bipolar renal length on ultrasound; unexplained pulmonary oedema; unexplained CRF with other vascular disease; worsening of renal failure with ACE inhibitor.

Hemodynamics Hemodynamic variables at these carotid bifurcations were calculated and visualized by combining vascular imaging post-processing and CFD. Results: A largest contiguous region of low velocity occurred at the carotid bulb. The eddy current and back fl ow was observed at bifurcation and outer part of proximal internal carotid and external carotid artery and the shapes of them changed with phase of cardiac cycle. The eddy current and back fl ow were signifi cant at middle of systolic phase and faded out quickly along downstream of internal carotid artery and external carotid artery. The wall shear stress map revealed a large region of low wall shear stress (WSS) at carotid bulb and extended to the outer wall in the proximal end of internal carotid artery, the lowest value was below 0.5 Pa. Also there was a small region of low WSS at the outer wall in the proximal end of external carotid artery. Conclusion: CFD combined with vascular imaging can calculate and visualize the hemodynamic variables at carotid bifurcation in vivo. It is an interdisciplinary science of computer, radiology and hemodynamics and provides a new method of investigating the relationship of vascular geometry and fl ow condition with atherosclerotic pathological changes.

Bloodpool-enhanced MR angiography: Optimization of scan protocols, evaluation and combination of conventional fi rst-pass with steady-state ultra-high spatial resolution imaging T. Leiner, R.N. Planken, M.W. de Haan, J.M.A. van Engelshoven; Maastricht/NL (leiner@rad.unimaas.nl) Learning Objectives: To provide practical guidelines on how to perform blood poolenhanced high-quality fi rst-pass and ultra-high spatial resolution steady state MR angiography of abdominal and peripheral arteries using the latest technological developments, and how to evaluate such studies in order to maximize diagnostic yield. Background: The recent introduction of the clinically approved blood pool agent Vasovist enables steady state imaging of vasculature in addition to conventional fi rst-pass imaging. Because of the increased distribution volume of the agent, there are major differences with regards to choice of optimal imaging parameters. Procedure Details: Despite the much lower dose (0.03 mmol/kg vs. 0.3 mmol/ kg) and injection volume (9.0 vs 45.0 mL for a 75 kg person), fi rst-pass imaging yields equivalent image quality at identical imaging parameters. Ultra-high spatial resolution equilibrium-phase imaging on the other hand demands increase of TR, decrease of bandwidth and fl ip angle to maximize vessel-to-background contrast. Images are best evaluated in the transverse plane as well as with curved multiplanar reformations.

The major teaching points of this exhibit are: 1) Ultra-high spatial resolution steady state MR angiography of abdominal and run-off arteries is feasible in several minutes with voxel sizes in the order of 100-500 microns. 2) When using ultra-high spatial resolution, acquisitions venous enhancement will no longer interfere with image evaluation and assessment of disease. 3) Because of the much longer intra-vascular residence time, blood pool agents enable imaging of additional arterial territories. Learning Objectives: 1. To illustrate the MR angiographic appearance of the different recanalization procedures used to treat ischemia of the lower extremities. 2.

To review the complications following surgery including obstruction, stenosis and pseudoaneurysm formation. Background: Three-dimensional contrast-enhanced MR angiography represents a good alternative to catheter digital subtraction angiography (DSA) to assess peripheral artery graft patency. MR angiography is safer, faster, and less costly than DSA. Postoperative graft surveillance is of particular importance, because fl ow impairment is the major cause of graft failure. It is important to detect early graft stenosis to improve the bypass patency rate. Venous and expanded polytetrafl uoroethylene grafts are used to treat peripheral artery occlusion. Autologous venous grafts have a primary and secondary graft patency superior to that of expanded polytetrafl uoroethylene grafts. Imaging Findings: MR angiography can identify accurately graft stenosis involving the proximal and distal anastomosis as well as the midportion of the graft course. Aneurismal ectatic changes can also be assessed on MR angiography. Metallic clip presence can represent a limitation on MR angiography; the susceptibility artifact produced by the clips can produce a misinterpretation of the images. Source images should be evaluated to avoid misinterpretation of clip-induced susceptibility artifacts as stenosis.

We present our experience with MR contrast-enhanced angiography for the evaluation of different types of vascular grafts used to treat peripheral arterial stenosis. We show the normal fi ndings, the complications and limitations we have found on MR images, using the DSA as a gold standard technique.

Color Doppler sonography before, during and after endovenous saphenous laser ablation A. Cina, S. Venturino, C. Di Stasi, A. Fiorentino, G. Cina, L. Bonomo; Rome/IT (acina@sirm.org)

Learning Objectives: To describe the principles and technique of endovenous laser treatment of saphenous vein refl ux. To illustrate the color Doppler US (CDS) criteria for selecting patients suitable for the procedure. To teach how to perform CDS during the procedure. To show CDS fi ndings during follow-up and how to evaluate the outcome of the procedure. Background: The procedure of endovenous laser ablation of the saphenous vein is simple and effective, with minimal side effects. CDS is fundamental in selecting patients for the procedure, during the procedure and to verify the outcome of the treatment at the follow-up. Procedure Details: Advantages and limits of the procedure. CDS criteria for selecting and excluding patients. CDS data required for the treatment. Echo-guided puncture of the saphenous vein. Checking the correct positioning of the laser probe. CDS guide for the tumescent local anaesthesia. Ruling out complications on the deep venous system. Follow-up: How to evaluate the effectiveness of the treatment. Tips and tricks of the procedure. Conclusion: This exhibit will provide the knowledge necessary to perform CDS before, during and after the endovenous treatment. The exhibit will also review anatomy, technique, CDS inclusion and exclusion criteria for the treatment.

Temporal arteritis: Avoidance of unnecessarily performed biopsies after color Doppler US evaluation E. Antypa, A. Baltouka, A. Parlamenti, M. Skilakaki, D. Ziaka, T. Kratimenos, P. Piperopoulos; Athens/GR (baltoukamina@yahoo.com)

Purpose: The management of temporal arthritis is crucial, and the purpose of this study is to demonstrate the value of Color Doppler US (CDUS) in the diagnosis of temporal arthritis and to permit the reduction of unnecessarily performed biopsies. Methods and Materials: CDUS was performed in 32 patients, mean age 72 years, with clinical suggestion of active temporal arthritis. None of the patients was treated with cortical steroids previously. Linear high-frequency transducers, 10-15 MHz, were used. The common temporal artery and its branches, frontal and parietal, were examined in all patients. The main sonographic criterion for a positive diagnosis was visualization of a periluminar hypoechoic halo and the suspicious areas were marked. Biopsy was performed in all patients. Additionally, in patients with positive CDUS fi ndings of temporal arthritis, the biopsy was guided at the indicated suspicious sites. Results: CDUS fi ndings suspicious of temporal arthritis were reported in 14 patients. In all of them, the biopsy results were positive for temporal arteritis.The biopsy results in the remaining 18 patients were negative, as were the CDUS fi ndings.

The method of CDUS evaluation of temporal arthritis, using a linear high-frequency transducer and assessing the characteristic sign of periluminal hypoechoic halo, leads to the direct diagnosis of temporal arthritis, and allows a proper medical approach to the disease. Moreover, CDUS guides the biopsy at the indicated areas and, additionally, contributes to avoid surgical biopsy in selected patients with typical sonographic fi ndings.

The use of contrast-enhanced ultrasound in detecting type-II endoleaks after endovascular abdominal aortic aneurysms repair (EVAR) A. Drelich-Zbroja, T. Jargiello, A. Drop, E. Czekajska-Chebab, M. Szczerbo-Trojanowska; Lublin/PL (zbroanna@interia.pl)

Purpose: To assess the effi cacy of contrast-enhanced ultrasound in detecting type-II endoleaks in the aneurysmal sac after EVAR. Methods and Materials: During the period 2005-2006, standard and contrastenhanced ultrasound with the use of SonoVue were performed in 86 patients who underwent EVAR. Ultrasound examinations and spiral CT were done 12 months after EVAR. The evidence of endoleak type II was evaluated.

Results: In conventional Doppler study, type-II endoleaks were diagnosed in 3 patients, 2 from lumbar arteries (LA) and 1 from inferior mesenteric artery (IMA). Contrast-enhanced ultrasound examinations revealed type-II endoleaks in 9 patients, 6 from LA and 3 from IMA, and showed different mechanisms of C 509 B D E F A G endoleaks: 2 complex type-II endoleaks and 7 simple endoleaks. All endoleaks were characterized by slow velocities with Vmax from 11 cm/s to 18 cm/s. CT examinations detected type-II endoleaks from IMA in 4 patients and confi rmed 3 endoleaks from IMA diagnosed with the use of SonoVue and indicated 1 additional endoleak from IMA. CT examinations showed only 5 type-II endoleaks from LA. There was 1 more endoleak from LA diagnosed with the use of SonoVue, which was not detected during CT. Conclusion: The use of ultrasound contrast agents increased the diagnostic effi cacy of Doppler examinations for detecting type-II endoleaks. This examination is comparable to CT value in detecting type-II endoleaks, but contrast-enhanced ultrasound examinations additionally show the mechanism of endoleak and the direction and velocities of blood fl ow. Purpose: Insulinoma is a rare functional pancreatic neuroendocrine tumor, usually localized in the body and tail of the pancreas. Diagnosis is highly diffi cult, and performed by computed tomography, magnetic resonance and selective angiography of the pancreatic arteries by digital subtraction angiography (DSA).

The purpose of the study was to analyze the diagnostic assessment of pancreatic DSA, computed tomography and magnetic resonance in 28 patients (21 females, 11 males; 41+8 years) with insulinoma. The tumors were localized in the pancreatic body in 17/28 patients (60.71%), in the pancreatic tail in10/28 patients (35.71%) and in 1/28 patient (3.57%) in the head of the pancreas. The diagnosis was confi rmed by pathohistology after the surgical treatment in all patients. The tumors were 12-49 mm in diameter and well vascularized. Results: DSA detected insulinoma in 21/28 patients (sensitivity 75%). Computed tomography detected insulinoma in 11/28 patients (sensitivity 39.28%, p < 0.05 vs. DSA), whereas magnetic resonance detected tumors in 15/28 patients (53.57%, p < 0.05 vs. DSA). In 7 patients in whom DSA failed to detect insulinoma, the diagnosis was achieved by computed tomography or magnetic resonance. The potential causes for DSA's failure to detect insulinoma are poor vascularization of the tumor and presence of extra gasses in the bowel. Conclusion: Digital subtraction angiography has better sensitivity than computed tomography and magnetic resonance imaging. So, it has a major role in the detection of insulinoma.

Lower limb venography: The forgotten "gold standard" A. Saini, N. Fotiadis, P. Goutzios, R. Dourado, F. Kazmi, R. Salter, C. Sandhu, T. Sabharwal, A. Adam; London/UK Learning Objectives: Over the last ten years, dulpex ultrasound has become the primary modality used to assess lower limb venous disease. As a result, the use of contrast venography has declined and in some institutions is rarely performed. This pictorial review is based on the authors' experience and aims to review the indications, techniques, venous anatomy and pathology as demonstrated by lower limb contrast venography. Background: Contrast venography has long been considered the 'gold standard' in the assessment of lower limb veno-occlusive disease and can effectively demonstrate thrombus within the below knee veins. Since duplex ultrasound has the advantages of being non-invasive and does not use ionising radiation, it is favoured by both clinicians and patients as the initial diagnostic test for deep vein thrombosis. Radiologists in training no longer have the exposure previously available and may not be familiar with the techniques or the appearances of common pathology. Procedure Details: The indications, technique and radiological appearances of lower limb venography are illustrated. Emphasis is placed on common anatomical variants that are often poorly recognised by routine duplex ultrasound. The use of venography in the assessment of venous malformations, venous tumour encasement and in the post-phlebitic limb are also discussed. Conclusion: Venography remains the 'gold standard' in the assessment of lower limb venous disease. However, since this method is no longer in frequent use, it is imperative that radiologists remain familiar with the current indications, technique and interpretation of the test.

A novel delivery system for hand injection of carbon dioxide in digital subtraction angiography M. Cherian, P. Mehta, P. Gupta, B. Madhavram, S.R. Jayesh, T. Kalyanpur, V. Ilayaraja, N. Sekhar, S. Hedgire, D. Raja; Coimbatore/ IN (drprashg@gmail.com) Learning Objectives: To demonstrate the feasibility of a plastic bag injection system for a hand injection of carbon dioxide in digital subtraction angiography. Background: Iodinated contrast agents are routinely used in procedures to diagnose and treat peripheral vascular disease. These agents are associated with contrast-induced nephropathy and allergic reactions in some individuals. To overcome these problems, carbon dioxide angiography has been developed as an alternative to standard iodinated contrast angiography. Conventionally available CO 2 injectors are expensive and require specialized cylinders which are not currently available in India. We developed a simple plastic bag delivery system to perform CO 2 angiography at our hospital. Procedure Details: The problems associated with carbon dioxide: (1) CO 2 comes in large cylinders under high pressure and thus the pressure has to be reduced close to atmospheric pressure before it is injected.

(2) CO 2 is colorless and requires closed circuit to prevent contamination with air. A blood bag was used in the circuit to reduce the pressure equal to that of the atmosphere and CO 2 was aspirated through a three way stop cork into a 50 ml syringe. Angiography was then performed in the lower limb arteries of 10 patients. Digital subtraction angiography performed with a hand injection of carbon dioxide depicted the vessels in adequate detail in all the patients.

We demonstrate a simple, safe and inexpensive system that delivers a known volume of CO 2 at atmospheric pressure and effectively prevents contamination with room air. Mallard, and so on) were studied and systemized in chronological order. We describe the works of the authors who were pioneers in vascular imaging, and whose works were historical landmarks.

We display the progress that has been made in vascular imaging from conventional angiography to modern MRI angiography.

C 513 B D E F A G aneurysms in 14 patients. This study included 13 men and 1 woman (mean age: 70 years). One radiologist reviewed 13 computed tomographic (CT) studies, 5 arteriograms, 3 magnetic resonance (MR) studies and one Doppler sonography. Features evaluated included aneurysm size, shape, and location; branch involvement; arterial wall calcifi cation; gas; and periaortic and associated fi ndings. Results: Aneurysms were located in the thoracic aorta (n=5.5%), thoracoabdominal aorta (n=11%), infrarenal aorta (n=27.7%), iliac artery (n=27.7%), femoral artery (n=5.5%), tibial-peroneal arterial trunk (n=5.5%), and peripheral middle cerebral artery (n=16.6%). Four patients had 2 infected aortic aneurysms.CT revealed 17 saccular (n=94.5%) and 1 fusiform (n=5.5%) aneurysms. Paraarterial soft-tissue mass, stranding, and/or fl uid were present in 10 (n=55.5%) of 18 aneurysms, and early periarterial edema with rapid aneurysm progression and development was present in 2 (100%) patients with sequential studies. Other fi ndings included psoas muscle abscess (n=5.5%), absence of calcifi cation in the aortic wall (n=44%), and periaortic gas (n=11%). Angiography showed 5 saccular aneurysms with lobulated contour in 2 (40%). MR imaging showed 3 saccular aneurysms. Conclusion: Saccular aneurysms with rapid expansion and adjacent mass, stranding, and/or fl uid in an unusual location are highly suspicious for an infected aneurysm.

Chronic mesenteric ischemia: Imaging fi ndings S. Jiménez, A.B. Delgado, A. Sánchez, Y. Revilla, A. Martínez, E. García;

Learning Objectives: To describe the imaging fi ndings of chronic mesenteric ischemia (CMI) on duplex ultrasonography (DUS), and their correlation with computed tomography angiography (CTA), magnetic resonance angiography (MRA) and angiography. Background: CMI is an unusual but important cause of abdominal pain and weight loss, resulting from occlusion or severe stenosis of at least two of the three main splachnic vessels. Understanding abdominal visceral circulation, its variants and collateral pathways that develop in patients with visceral artery stenosis is key to recognize CMI. Atherosclerosis is the main cause of CMI (95% cases), usually involving the ostium of celiac artery (CA), superior or inferior mesenteric artery (SMA or IMA). Other rarer causes are nonatheromatous lesions (dysplastic lesions, thromboangitis obliterans, radiation-induced lesions, Takayasu arteritis…). Imaging Findings: Evidence of visceral artery occlusion with noninvasive imaging such as DUS, CTA or MRA could suggest CMI, if other causes of abdominal pain have been confi dently ruled out. In DUS a peak systolic velocity greater than 275 cm/sec or end-diastolic velocity greater than 45 cm/sec seems highly specifi c for signifi cant SMA stenosis. Vascular obstructions, stenosis, collateral pathways and changes in the bowel wall can be depicted on both CTA and MRA. If endovascular treatment is proposed, angiography remains the diagnostic gold standard. Conclusion: DUS, as the preferred noninvasive screening test for SMA and CA stenosis, followed by CTA, MRA or angiography allow us to make the diagnosis of CMI, as well as a valuation of extension, severity and number of affected arteries.

Takayasu's arteritis: A multi-modality pictorial essay J.P. Banerjee, V. Prabhudesai; Hamilton, ON/CA (pjbanerjee@hotmail.com) Learning Objectives: To better appreciate the imaging characteristics of Takayasu's Arteritis based on various modalities and thereby improve detection and surveillance of disease activity. Background: Imaging characteristics play a critical role in the diagnosis of Takayasu's Arteritis given that both clinical presentation and serological markers are non specifi c. Traditionally, angiographic studies have primarily been used to demonstrate the vascular effects of this disease. However, employing additional and/or alternative modalities provide a more complete understanding of Takayasu's Arteritis. Our institution serves as a local referral base for rheumatologic conditions and the Department of Medical Imaging is routinely consulted in cases of suspected vascultitis. We have selected a group of patients whose imaging best illustrates the salient features of this clinical entity. The benefi ts and shortfalls of angiography, ultrasonography, contrast enhanced CT and MRI are reviewed and a pictorial essay is offered to illustrate various fi ndings using these modalities. Imaging Findings: While angiography is the traditional gold standard for investigation of vasculitides, ultrasonography provides a non invasive alternative with fewer side effects, albeit at the expense of lower predictive value and operator dependance. Cross sectional imaging by means of CT and MRI also offer non invasive visualization of luminal pathology with the additional benefi t of demonstrating changes within the wall. Conclusion: Although knowledge of angiographic fi ndings of Takayasu's Arteritis aid in the evaluation of this disease, familiarity with imaging characteristics of other modalities allow the radiologist to better assess patients and offer additional and less invasive imaging options.

Current radiological approach for the diagnosis and follow-up of Takayasu arteritis A.Y. Goktay, A. Gulcu, T. Celik; Izmir/TR (yigit.goktay@deu.edu.tr)

Learning Objectives: To evaluate the combined use of Doppler US, MRI, MR Angiography and DSA for the diagnosis and follow-up of Takayasu arteritis. Background: Takayasu arteritis is characterized by granulomatous infl ammation of the arterial wall which eventually leads to stenosis, occlusion and sometimes aneurysm formation. Classical diagnosis has been based on characteristic fi ndings of the aorta and its major branches at conventional angiography or DSA. However, current developments in the fi eld of cross-sectional imaging have increased the diagnostic capacity of radiological methods even in the early systemic phase without any luminal abnormality. We present the combined radiological approach for the patients with Takayasu arteritis. Procedure Details: Cervical, renal, abdominal and extremity arterial Doppler US examinations were performed for obtaining direct and indirect information about arterial fl ow and vessel wall. Thoracoabdominal MRI and MR Angiography studies were performed on a 1.5 T scanner with body coil. Multiplanar T2-weighted fat-suppressed, T1-weighted black blood inversion recovery before and after administration of Gd-DTPA and contrast enhanced 3D MR angiography sequences were obtained. Image interpretations were performed after post-processing studies. All luminal fi ndings were compared with DSA results. During the follow-up, US and MRI fi ndings about vessel wall thickening and contrast enhancement of arterial wall were also evaluated. If necessary, endovascular treatments were performed according to the activity of the disease. Background: DVT is a common vascular disease requiring prompt diagnosis and treatment but clinical assessment is often unreliable. D-dimer testing and pre-test probability scoring are used as guides for selection of the most appropriate investigation. Vascular imaging remains essential for diagnosis and B-mode and Doppler US, MDCT and MRI play an important role in the work-up of the disease. Procedure Details: The authors discuss advantages and limitations of each method in the evaluation of DVT, illustrating thoroughly the spectrum of fi ndings at US, MDCT and MRI. Technical principles are outlined as fundamental tools to optimise disease detection and avoid potential pitfalls. Conclusion: B-mode and Doppler US is a cost-effi cient and widely available technique for initial evaluation of suspected extremity DVT. MDCT and MRI allow visualisation of affected areas non-accessible to US imaging. MDCT with shorter acquisition times, greater coverage and reduced scan width provides excellent resolution in depiction of the disease, and detection of eventual complications as pulmonary thromboembolism.

Imaging features of the congenital and acquired abnormalities of the SVC and the pulmonary vasculature K. Burney 1 , H. Young 2 , P. McCoubrie 2 , S. Barnard 2 , M. Darby 2 ; 1 Southampton/UK, 2 Bristol/UK (kburney@doctors.org.uk)

Learning Objectives: To illustrate the spectrum of congenital and acquired abnormalities of the superior vena cava (SVC). To present the congenital anomalies of the pulmonary veins and the associated anomalous drainage patterns seen. Background: A wide range of clinical conditions can affect the SVC. These include both congenital and acquired abnormalities. Similarly, the pulmonary veins can be affected by a number of congenital anomalies, which can occasionally mimic other disorders and be associated with congenital heart disease. Imaging Findings: We retrospectively reviewed the imaging of patients with SVC or pulmonary venous abnormalities treated in our hospital, and present a review of abnormalities as seen on various radiological investigations including CT, MRI and plain fi lms. The congenital abnormalities of the SVC highlighted include left-sided and double SVC. Acquired abnormalities including intra luminal defects caused by line-associated thrombus, SVC stenosis secondary to multiple central line insertions or tumour invasion, extra luminal compression caused by mediastinal tumour and vascular aneurysms are demonstrated. Partial anomalous pulmonary venous return (PAPVR) is a congenital abnormality in which one or more of the pulmonary veins are connected directly to the right atrium or to a systemic vein. We also present various patterns of PAPVR as seen on contrast-enhanced CT, as they may be associated with congenital heart disease.

The development of the central systemic veins including the SVC and pulmonary veins is a complex process subject to a number of variations. Knowledge of some of the resulting variations can be of clinical importance.

Flow spectra were evaluated with Doppler scan mode and fl ow parameters were calculated for the femoral, popliteal and calf arteries and veins. Results: HIT was proven by a positive platelet aggregation test in 20 patients (36%), 11 females and 9 male, who suffered lower extremities thromboembolic complications. Fifteen patients (75%) had arterial thrombosis, most prominent of the common femoral, superfi cial femoral and posterior/anterior tibial artery. Six subjects (30%) had deep venous thrombosis, most prominent of the common femoral and superfi cial femoral vein. Conclusion: Our study confi rmed the remarkably high incidence of thromboembolic complications, mostly arterial, in critically ill patients with HIT. The routine CDUS is appropriate in these patients since if silent arterial or venous thrombosis is identi

Developmental dysplasia of the hip in children: Can MRI features predict the need for surgical oseotomy? N. Chew, P. Mitchell, I. Goutos, S. Evans, A. Hulme, J. Lee, J. Healy; London/UK (drchew@doctors.net.uk) Purpose: Open or closed reduction is undertaken to facilitate normal hip growth in children with DDH. However, a proportion of children who undergo hip reduction fail to develop deep well-formed acetabuli. These children will need to undergo pelvic osteotomy to improve cover of the femoral head and thereby reduce risk of premature osteoarthritis. We ascertain if the presence of abnormalities on MRI immediately after hip reduction can predict long term hip dysplasia, therefore, aiding surgical fore-planning and reducing need for follow-up radiographs. Methods and Materials: Nineteen hips with DDH were followed up over 4 years. All had initial reduction and post-reduction MRI. MRI fi ndings of 13 hips where acetabular dysplasia resolved by age four were compared with the 6 hips that underwent pelvic osteotomy for unresolving dysplasia. Cartilage anlage shape, bony acetabular index, acetabular anteversion, lateral displacement due to panniculus, ligamentum teres and transverse ligament thickness, and whether the acetabular labrum was in a normal position or folded into the joint were were analysed and compared. The scans were analysed by two consultant musculoskeletal radiologists who were blinded to the outcome of each child. Results: Statistical analysis found none of the abnormalities on MRI were predictive of persisting acetabular dysplasia in the older child. Conclusion: Although post reduction MRI demonstrates anatomical abnormalities secondary to DDH, none of these were predictive of long term acetabular dysplasia. This suggests that the factors determining long term outcome are not visible on MRI, but perhaps due to poor muscle dynamics or a biomolecular abnormality.

Radiological fi ndings in patients with Stuewe-Wiedemann syndrome surviving infancy R.D. Langer, L. Al-Gazali, P. Raupp; Al Ain/Abu Dhabi/ AE (rlanger@uaeu.ac.ae) Learning Objectives: To illustrate radiological fi ndings in the subgroup of patients with Stuewe-Wiedemann syndrome (SWS), surviving the second year. Background: SWS is a rare skeletal dysplasia. Mutations responsible have been recently identifi ed. The prevalence is high in the UAE (0.5/10,000 birth). Most SWS patients die before the age of 2. Out of 24 SWS patients, 6 survived the second year. All came for regular orthopedic and pediatric checkups, or were admitted due to respiratory distress. Patients received follow-up bone and chest radiographs; 1 underwent CCT. Our fi ndings have been compared to few published data. Imaging Findings: All children showed congenital dwarfi sm with progressive bowing of the extremities and demineralization. Three had metaphyseal enlargements with coarse trabeculae. Three developed progressive (kypho)-scoliosis and one spontaneous fracture. Three children showed fragmented epiphyses. Epiphyseal fl attening occurred in 4 patients. Metacarpals and metatarsals were shortened and undertubulated. One patient developed an osteonecrosis of the talus. Rips were broadened and osteoporotic with old fractures. All survivors repeatedly received chest radiographs due to aspirations, pulmonary infections, and pneumonias. Two patients expired subsequently; they died from respiratory insuffi ciency. One girl developed a neurological defi cit due to left frontal infarction, which was caused by hypoxia. Conclusion: While Maroteaux reported a mean survival time of 2 months, several cases surviving infancy have been published, and are under surveillance. SWS survivors after the second year show progressive bowing of the extremities with osteoporosis, a tendency to fractures, metaphyseal abnormalities, and severe (kypho)-scoliosis. Pulmonary infections are less frequent after the second year. Conclusion: The image plates will tested more with the phantom and after that the results will be tested with clinical use. The experienced radiology will analyse the image quality. The results will be introduced. These fi rst tests showed that it is possible to optimise the radiation dose and image quality easily according to the DIMONDIII process.

Optimization of patient exposure dose in low-dose scanning for CT colonography by adjusting dose according to patient weight Y. Hirano, K. Sasaki, H. Matsuya, S. Katsuki, K. Sasaki; Otaru city, Purpose: Reducing patient exposure dose is important in CT colonography. In a previous study (ECR 2005) , we studied laboratory models and found that scanning with an air SD value (standard deviation value in the acrylic part) of approximately 35 or more results in poor visualization. Air SD values vary according to patient size. In the present study, we investigated optimization of the patient exposure dose by adjusting the dose according to patient weight. Methods and Materials: Patients were examined using a 16-row multidetector CT scanner and a 3D workstation. Patient weight was measured before CT colonography. Scanning was performed with an extremely low dose of 5 mAs (70 patients) or 15 mAs (37 patients), and the air SD values in the colon were determined in the upper abdomen and in the pelvic cavity. Scan conditions were 120 kV, 1.0-mm scan slice thickness, and 1.0-mm reconstruction slice thickness. Results: A positive correlation was observed between patient weight and air SD values in the colon. The correlation coeffi cients were 0.74 and 0.73 in the upper abdomen and 0.69 and 0.72 in the pelvic cavity for extremely low-dose scanning at 5 mAs and 15 mAs, respectively. Conclusion: Our previous study (ECR 2005) showed that air SD values of approximately 35 or more result in poor visualization, making it diffi cult to observe the tissue surface. The present study has shown that adjusting the dose according to patient weight is useful for optimizing the patient exposure dose in low-dose scanning while maintaining good visualization.

How versatile is CT-AEC? Radiographic technique considering performance characteristics K.O. Oosawa 1 , Y.M. Muramatsu 2 , S.T. Terakawa 3 , T.M. Mito 3 , S.N. Nakahira 3 , Y.H. Hamada 3 , Y.U. Ueda 3 , I.F. Fujimura 3 ; 1 Sakurai Nara/JP, 2 Chiba/JP, 3 Osaka/JP (alfa-k155@t-kadomatsu.net) Purpose: CT automatic exposure control (CT-AEC) is a new technique to optimize increasing exposure during CT examination. Because different CT-AEC systems use different operational principles, CT-AEC cannot be expected to be effective when used thoughtlessly. The purpose of this study is to develop a radiographic technique that considers performance characteristics of different CT-AEC systems, pursuing maximum dose reduction while ensuring image quality. Methods and Materials: Two CT-AEC systems from one manufacturer were investigated: (1) SOMATOM Volume Zoom with CARE Dose, and (2) Sensation 64 with CARE Dose4D (Siemens, Germany). The phantoms for evaluation are cone, elliptical, variable-XY and step phantoms (Kyoto Kagaku, Tokyo). Data was collected by changing abdominal CT scan parameters as appropriate. The data was converted to DICOM images; image noise, tube current and absorbed dose (CTDIw) were obtained using a dedicated software program (BioArts, Fukuoka).

The relationship between tube current and image noise was compared for CARE Dose and CARE Dose4D. Dose reductions from 10% to 30% were obtained in both AEC systems compared with doses obtained without AEC. While dose reduction depends on phantom size in both systems, the dependence changes with dose correction curves in CARE Dose4D. The dependence of image noise on phantom shape is observed in CARE Dose, but is not conspicuous in CARE Dose4D. Conclusion: A tube current correction table considering phantom size and shape was developed from the results, allowing dose reduction and comparable image quality from the two systems.

Can the isolated distension of the colon be infl uenced by adequate preparation during virtual colonoscopy, or, if needed, can adequate small intestine distension also be achieved? E. Turupoli, K. Szeidl, L. Fehér, Á. Szilvássyné Takács; Budapest/HU (turupoli@freemail.hu) Purpose: To develop a method by which the isolated distension of the colon can be achieved, or if the status of the small bowel is also questionable, to produce the distension of small bowel too. Methods and Materials: We performed 190 virtual colonoscopies. The infl ation Conclusion: SD12 is the appropriate SD setting level for CT-AEC in abdominal CT examinations.

Usefulness and optimal noise (SD) of auto-mA: Survey among radiology technologists using16-slice MDCT and esophageal cancer phantom study N. Yanagawa, H. Satou, T. Kazama, T. Iimori, K. Shutou, S. Okazumi, T. Ochiai; Chiba/JP (yanagawa@ho.chiba-u.ac.jp) Purpose: Image quality and radiation exposure are confl icting factors. Recently, automatic determination of radiation dose (auto-mA) in CT scans has been developed. The purpose of this study was to determine optimal noise level at auto-mA. Methods and Materials: Questionnaire was mailed to 99 institutions that have 16-slice MDCT. The questions were usage of auto-mA, and the setting of noise level when it was used. A basic study was performed with small and large phantoms. The small (S)-phantom was a low-contrast phantom and 20 cm in diameter. The large (L)-phantom was made of the low-contrast phantom rolled with water-polymer absorber material. This was 35 cm in diameter. The largest diameter of the lesions demonstrating more than two-third of their profi le was searched. Results: Fifty-one institutions answered the survey. In 76% institutions, auto-mA was used and the standard deviation (SD) of auto-mA set between 6 and 15, but it was set constant in each institution. On phantom study when SD was set at 8, the largest profi le of lesions in L-phantom was 10 mm, while that in S-phantom was 12.5 mm. When SD was set at 10, the largest profi le of lesions in L-phantom was 12.5 mm, while that in S-phantom was 15.0 mm. Conclusion: Although SD of auto-mA was set constant in many institutions, phantom study suggested different optimal SDs depending on patients' body habitus.

Manual labeling of brain tissues on MR images -a method to assess the quality of brain tissue volumes by automatic segmentation in a large population based study: The age, gene/environment susceptibility (AGES)-Reykjavik study B. Oskarsdottir 1 , S. Sigurdsson 1 , L. Purpose: Automated segmentation of brain tissue on MR images is critical to accomplishing analyses of MR scans acquired in large population-based studies, but manually labeled tissue is needed to check the accuracy of the algorithms. Here we describe a method for manual labeling of brain tissues on MR images and assess the reproducibility of the method. Methods and Materials: The brain tissues on the MR images were labeled using "BorderLine", a software drawing tool specially designed for the AGES-Reykjavik study. BorderLine uses a Wacom pen tablet as a human interface device for drawing and labeling anatomical landmarks. The tablet comes with a computerized pen interface and a drawing board, allowing the user to label multiple ROIs or tissue classes based on a multi-modal set of registered brain images. Intra-rater variability was assessed based on 2 repeated measures from one observer on 5 pre-defi ned slices of the brain for cerebrospinal fl uid (CSF), gray matter (GM), white matter (WM) and white matter lesions (WML), based on the 4 following MR sequences: 3D SPGR T1, FSE PD/T2, and FLAIR T2. The intra-rater variability was calculated for each tissue class and each slice location individually using kappa statistics describing spatial agreement (Dice Similarity Coeffi cient). Results: Kappa agreement for all tissue classes and all slice locations was excellent (mean k=0.856±0.088 and mean k=0.899±0.009, respectively). Conclusion: A robust, highly reproducible method has been developed for manual labeling of brain tissues.

An evaluation of computer-aided instruction courseware for MRI physics D. Koumarianos, E. Mihalopoulou, L. Costaridou, G. Panayiotakis; Patras/GR (dikoum@panafonet.gr) Purpose: The evaluation of a computer-based instructional package designed to interactively teach MRI concepts using media-rich animations. Methods and Materials: Eighteen postgraduate students were prospectively, randomly assigned to receive instruction on the same MRI topic from a textbook and a computer module. Participants were evaluated by a multiple choice test 2 weeks before the lectures, at the end of the lectures and by a retention test after 1 month. They also completed questionnaires to rank their attitudes quantitatively and qualitatively toward the two instructional methods. Mean test scores of the textbook and computer groups were compared by means of analysis of variance. Results: The percentage of correct answers increased from 36.7% on the pretest to 70.3% on the posttest, and then decreased to 49.6% on the retention test administered 1 month after completion of the MRI course. Computer group students scored signifi cantly higher on their posttest (M=80.5, SD=9.4) when compared with the textbook group (M=61.3, SD=12.5, p=.003), while they seem to appreciate multimedia modules more when compared to textbook students (p=.003). The textbook learning group was equally satisfi ed with their method of instruction in comparison to the computer group (p=.230). Students' rationale for expanding the use of multimedia in physics education seemed to focus on issues concerning motivation, instructional capabilities and content. Conclusion: Interactive animations are a useful and effective aid for teaching MRI principles. The study demonstrated that the inclusion of properly designed multimedia modules enhances conceptual understanding far more than traditional methods do.

Atlas of normal and variant abdominal arteries. 3D anatomy with 64 channel multidetector-CT P. Sedati, G. Pelle, M. Telesca, F. Macrì, A. Napoli, C. Catalano, R. Passariello; Rome/IT (psedati@hotmail.com) Learning Objectives: 1. To illustrate basic liver and renal vascular anatomy and its variation with multiplanar and 3D imaging using 64 detector row CT. 2. To provide an atlas of normal and variant vascular 3D anatomy. 3. To illustrate the basic principle of multiplanar and 3D imaging using 3D workstation and to explain how to optimize image quality. Background: Multi-detector CT (MDCT) is now a standard type of clinical CT scanner. Appropriate post-processing of MDCT images enables the effi cient gathering of much more information than by just evaluating thin source images. Post-processing techniques are useful both in clinical situations and for educational purposes. However, incorrect use of these techniques may hide important information. Procedure Details: 1) Major vascular anomalies that involve the systemic arterial system of the abdomen are reviewed with emphasis on key imaging fi ndings and differential diagnostic features that allow for differentiation from other abnormalities. 2) Review most important post processing technique and how to avoid important error. 3) Understand which of such anatomical variants are related with specifi c clinical symptoms, syndromes or are important for a correct surgical planning. Conclusion: Recognition of abdominal vascular anomalies on imaging is important because several such variants may be associated with specifi c clinical symptoms, syndromes and other pathologic processes. Major vascular anomalies that involve the systemic arterial systems of the abdomen are reviewed with emphasis on key imaging fi ndings and differential diagnostic features that allow for differentiation from other abnormalities. Images were acquired in a multi-phase fashion: the arterial phase using bolus tracking technique (Smart-Prep), and the venous phase after a 70 second delay, at 2.5 mm of collimation, 2.5 mm of reconstruction interval, and 6 of pitch. The active bleeding sign (AB) was detected with mean attenuation values. Images were reconstructed and rendered with MIP and MPR algorithms. Image evaluation was carried out by two experienced abdominal radiologists in a blinded-end fashion, and inter-observer agreement (Cohen-Test) was obtained. Results: Attenuation values ranged from 100 to 180 H.U. Eighteen out of 20 patients had abdominal hemorrhage, whereas the AB sign was detected in 10 out of 20 patients. It was secondary to spontaneous bleeding from an intrahepatic pseudoaneurysm (n=1), rupture of a splenic artery pseudoaneurym (n=1), rupture of a giant renal angiomiolypoma (n=1), bleeding from an aorto-duodenal fi stula (n=2), bleeding from gastric ulcer (n=2), and rupture of a hepatic hemangioma (n=2). Almost perfect agreement was obtained between the two readers in the detection of the AB sign (k=0.82, CI=95%). Conclusion: MDCT angiography and MPR reconstructions allowed satisfactory detection of active hemorrhage. The AB sign precisely localized the bleeding site, and therefore should be considered before therapeutic planning.

Advantages and disadvantages of ECG-gated multislice spiral CT (MSCT) in the study of the thoracic aorta C. Sebastia, H. Cuellar, S. Quiroga, A. Evangelista, R. Boyé, A. Alvarez;

Learning Objectives: 1. To describe our protocol for studying the thoracic aorta with ECG-gated MSCT. 2.To demonstrate, with images and videos, the advantages of this technique for studying several thoracic aorta diseases. 3. To depict the pitfalls, artifacts and disadvantages of the ECG-gated technique for imaging the thoracic aorta. Background: Since January 2004, we have performed an ECG-gated MSCT technique in 27 patients with thoracic aortic disease (9 aneurysms-pseudoaneurysms of the ascending aorta, 3 type A acute aortic dissections, 6 chronic aortic dissections, 2 aortic coarctations, 1 patent ductus arteriosus, 3 postoperative ascending

Color Doppler sonography before and after AV haemodialysis fi stulas preparation A. Cina, C. Di Stasi, S. Venturino, E. Muto, L. Tazza, L. Bonomo; Rome/IT (acina@sirm.org)Learning Objectives: Purposes of this exhibit are: to describe how to perform a color Doppler sonography (CDS) examination before the creation of AV fi stulas for hemodialysis and to show normal CDS fi ndings and complications of AV hemodialysis fi stulas. Background: Surgically created Brescia-Cimino arteriovenous fistulas and prosthetic loop grafts are common vascular accesses for hemodialysis. Although angiography has been the traditional method of imaging, CDS is now the standard technique employed before the fi stula creation and for evaluating dysfunctional hemodialysis access. Procedure Details: Anatomy and surgical techniques -(1) CDS methodology of study; (2) CDS qualitative and quantitative data necessary before the fi stula preparation; (A) Normal fi ndings after fi stula preparation; (B) Complications: feeding artery occlusion; anasthomotic stenosis; venous stenosis; venous/graft thrombosis; anasthomotic pseudoaneurisms; infections; radial steal. Conclusion: In this exhibit, we describe the role of CDS in selecting arteries and veins for the preparation of AV fi stulas for hemodialysis and the sonographic fi ndings of the more frequent complications. A detailed description of CDS examination protocol before and after the fi stula creation is reviewed. Purpose: The renal resistive index (RI) measured by Doppler US has a well known prognostic signifi cation in vascular nephropathies and an elevated RI is currently associated with the diagnosis of nephroangiosclerosis. Its value is more controversed in parenchymal nephropathies or in renal transplanted patients. Our study correlated the RI with renal intraparenchymal parameters: endarterial sclerosis (ESc) and interstitial fi brosis (IF). Methods and Materials: The RI of 81 consecutive patients were measured by Doppler US, just before renal biopsy. RI results were given as mean of 3 measurements performed at upper, lower and middle poles. The biopsy was made for the diagnosis of nephropathy (n=31) or for decline of renal function of kidney allograft (n=50). A histomorphological analysis was performed, using an automated methodology to determine the IF and ESc index. These parameters were correlated with the calculated RI for each patient (Mann-Whitney test). Other parameters were evaluated especially creatininemia (Cr) and Cockroft Glomerular fi ltration rate (CGFR). Results: For patients having a native kidney biopsy, an independent positive qualitative and quantitative correlation statistically signifi cant, could be made between RI and Cr, decline in CGFR, and ESc index. No relation was noted with the IF index. Correlations were not signifi cant for transplanted patients. Conclusion: RI is an exclusive non invasive index to diagnose the vascular sclerosis in native kidney and an elevated RI is a marker of poor prognosis renal function evolution in patients having nephropathy and chronic renal failure.

Colour Background: Celiac-mesenteric insuffi ciency is characterised by a hyper-affl ux to the celiaco-mesenteric district that may manifest itself asymptomatically, by means of aspecifi c pictures characterised by post-prandial pain (angina abdominis), or by means of dramatic conditions such as intestinal infarction. The risk factors are obesity, dyslipidemia, cigarette smoking, and antomical malformations such as fi bromuscular dysplasia, a high origin of the celiac tripod or hypertrophy of the arcuate ligament. Procedure Details: The fi rst diagnostic step when evaluating non-acute celiacmesenteric insuffi ciency is colour Doppler US, which allows us to localize the site of the stenoses and measure their severity (expressed as% stenosis). We show the technique of performing such an examination and describe the semeiotic principles underlying it and B-mode echography: the evaluation of the presence of plaque, post-stenotic dilatation, and the quantifi cation of the degree of stenosis by means of the assessment of direct and indirect signs; and the colour Doppler effects and fl ow acceleration. Conclusion: The exhibit will review the indications and techniques, and provide the tips and tricks, and a complete case gallery.

Helical Background: B-fl ow sonography is a relatively new sonographic technique that directly depicts blood echoes in a gray-scale presentation. This technique utilizes digitally encoded US technology and allows simultaneous imaging of blood fl ow, vessel walls and neighbouring tissues. The main imaging parameters are few (sensitivity, background control, gain control, focus number and location) and easy to use. Imaging Findings: B-fl ow sonography has several advantages over color and power Doppler sonography: The information from both tissue and blood fl ow is identifi ed in higher resolution and higher frame rates. Angle dependency, overwriting of the vessel walls by the color overlay, aliasing and perivascular color artifacts are eliminated. Major indications for B-fl ow and areas of research are as follows: evaluation of carotid artery lesions and stenoses; follow-up of carotid artery stents; evaluation of hemodialysis fi stula patency and complications; evaluation of pseudoaneurysms and guidance for therapy; lymph node characterization; and abdominal applications like the investigation of portal vein thrombosis, cavernous transformation of the portal vein and Budd-Chiari syndrome. The technique has also some limitations such as decreased sensitivity with increasing depth and inability to obtain signals from a structure located deep to a calcifi ed plaque. Also, fl ow directions are more easily recognized by color Doppler than by B-fl ow. Conclusion: B-fl ow technique provides higher resolution and higher sensitivity to fl ow without Doppler artifacts. Further improvements in the technique may overcome limitations and expand its clinical applications. Learning Objectives: 1. Give an overview of the anatomy of the jugular, subclavian and axillary veins. 2. Explain the techniques of cannulation of these veins, based upon anatomical landmarks, and correlate them with ultrasound (US)-guided approaches. Background: Central line catheterization is a clinically useful tool, performed for invasive monitoring the hemodynamic, respiratory, and fl uid status of patients, as well as for delivery of drugs and nutritive solutions. Classically, techniques based upon anatomical landmarks have been used, but that may fail if any vascular anatomic variant exists. Moreover, these techniques may cause complications as pneumothorax and hemorrhage after arterial injury. Procedure Details: After giving an overview of the anatomy of neck and shoulder, with special attention on anatomical relationships of veins, we expose the different catheterization techniques based upon anatomical landmarks. Jugular vein can be catheterized by anterior, medium or posterior approaches, and subclavian vein by infra or supraclavicular approaches. US-guided cannulation technique is correlated with each of these approaches. Finally, advantages and disadvantages of both techniques are summarized. Conclusion: Based on current literature, US can play an important role in the guidance of cannulation of central lines, as it can detect anatomical variations and venous thrombosis prior to the catheterization. Nevertheless, it may reduce complication rates and number of attempts during catheterization.

Morphologic and hemodynamic study of gastrocnemius medial vein with color duplex ultrasonography in chronic venous insuffi ciency S. Jiménez, A.B. Delgado, A. Sánchez, P. Martín, S. Zubicoa, J. Leal; Madrid/ES (sarajimenezarranz@gmail.com) Purpose: To describe the morphologic changes and hemodynamics of the gastrocnemius vein (GV) in patients with chronic venous insuffi ciency (CVI) with color duplex ultrasound (CDUS).

The study was performed in 222 lower limbs of 111 patients. 149 lower limbs presented clinical signs of CVI according CEAP classifi cation and 73 lower limbs were normal. We carried out an anatomical study of the GV and muscle, and provided hemodynamic information about the incompetent veins by demonstrating the presence of refl ux. Results: In 30% of limbs, the GV showed no refl ux and connections with superfi cial varicose veins through May's perforating veins (Re-entry veins). 14% had GV refl ux associated with superfi cial varicose veins, in 2% the refl ux was due to post-thrombosis syndrome, and in 6% the refl ux was interpreted due to primary incompetence (no superfi cial varicose veins and no evidence of deep venous thrombus). 14% presented mainly GV stasis (enlargement, slow fl ow and symptoms of pain), and 10% displayed asymptomatic dilatation. In 22%, the study was normal (no enlargement and no refl ux), and the remaining 2% showed gastrocnemius muscle atrophy with dysfunction of muscular pump. The GV mean diameters in the CVI group were larger than those of the non-CVI group (0.82 cm vs. 0.53 cm). We also measured the venous fl ow velocities and fl ow-volume after muscular systole in the different groups. Conclusion: CDUS is a non-invasive technique that allows anatomical and functional studies of the GV in patients with CVI. It is also useful for physiopathological classifi cation and pre-therapeutic evaluation.

Arterial and venous thromboembolic complications in heparin-induced thrombocytopenia (HIT) patients: Color Doppler sonography evaluation A. Balanika, M. Theodorakopoulou, M. Lignos, C. Baltas, E. Melissari, A. Gouliamos, A. Armaganidis; Athens/GR (mpaltas@hotmail.com) Purpose: Heparin-induced Thrombocytopenia (HIT) is estimated to occur in 1-5% of all patients receiving heparin. The purpose of this study was to investigate by color Doppler ultrasonography (CDUS) the incidence of thromboembolic complications in medically critical patients with HIT. Methods and Materials: Over a period of eighteen months, 55 Intensive Care Unit (ICU) patients (aged 39-89) presented with thrombocytopenia were investigated for HIT and underwent arterial and venous CDUS examination of lower limbs. Orthopedic, surgical and cardiosurgical patients were not included in the study. We evaluated

Advanced multi-modality imaging of therapeutic angiogenesis and arteriogenesis: Experimental in-vivo applications K. Katsanos, D. Karnabatidis, A. Diamantopoulos, G.C. Kagadis, P. Kraniotis, D. Siablis; Patras/ GR (katsanos@med.upatras.gr) Learning Objectives: To familiarise radiologists and research scientists with advanced cross-sectional and angiographic in-vivo imaging modalities for the study of experimentally induced therapeutic angiogenesis and arteriogenesis. Background: Therapeutic angiogenesis (new vessel growth) and arteriogenesis (collateral vessel enlargement) constitute the frontiers of cardiovascular research in the reversal of ischemic myocardial and peripheral arterial diseases. In-vivo vascular imaging allows the quantifi cation of the angiogenic process and is necessary for the reproducible morphological and functional investigation of novel proangiogenic agents. Imaging Findings: Experimental models of hindlimb or myocardial ischemia generally involve surgical or endovascular occlusion of the femoral or coronary arteries in animals. After the endogenous angiogenic response comes at rest, exogenous proangiogenic growth factors are administered and the evolution of therapeutic angiogenesis and collateralization is followed-up. Non-contrast and contrast-enhanced cross-sectional studies with computed tomography (CT) and magnetic resonance (MR) may depict variations in tissue vascularity and enhancement after administration of contrast media. Multiplanar reformatting along with volume-rendered CTA and/or MRA images may accurately display the morphology and bridging points of collateral vessels with diameter > 250 µm. Moreover, dynamic image acquisitions during contrast administration and corresponding perfusion studies permit the functional assessment of the newly developed collateral vessels. Finally, intra-arterial digital subtraction angiography delineates the newly formed vessels with great anatomic detail. Recently developed post-processing computerised algorithms provide the capacity of segmentation, visualisation and quantifi cation of microvessels with diameters down to 50-100 µm. Conclusion: Modern applications of cross-sectional and angiographic vascular imaging with advanced post-processing and reformatting algorithms enable in-vivo morphological and functional experimental studies of therapeutic angiogenesis and arteriogenesis.

Imaging spectrum of the infectious and infl ammatory etiologies of aortitis R. Suri, C.S. Restrepo, K.N. Chintapalli, S.R. Prasad, D.W. Postoak, B. Toursakissian; San Antonio, TX/US (suri@uthscsa.edu) Learning Objectives: 1. Review the clinical spectrum of infectious and infl ammatory conditions of the aorta. 2. Highlight the role of cross sectional imaging in the diagnosis and assessment of the extent of aortitis, thus helping in the management of these patients.Background: Infl ammatory/infectious conditions of the aorta and its major branches may present with nonspecifi c symptoms and are often missed clinically in the workup for fever of unknown origin (FUO). Increased awareness of aortitis would facilitate appropriate management. Imaging Findings: 1. Clinical signifi cance of aortic and major arterial infl ammatory conditions. 2. CT/MR/angiographic techniques and the role of image post-processing for dedicated evaluation of the aorta. 3. Pictoral review of cross sectional imaging of a wide spectrum of aortitis due to vasculitidis (Takayashu's arteritis, giant cell arteritis) and infection (granulomatous and other bacterial) involving the native aorta or after endograft or surgical repair. Conclusion: Increased awareness of aortitis and knowledge of the cross sectional imaging appearances helps to establish accurate diagnosis, which facilitates appropriate medical or surgical management. Early diagnosis with CT and MR avoids life-threatening complications, thus, decreasing morbidity and mortality.

A comprehensive pictorial review of anomalies of the superior and inferior vena cava E. Sueyoshi, I. Sakamoto, M. Uetani; Nagasaki/JP Learning Objectives: To provide a pictorial review of the embryology and anatomy of the superior and inferior vena cava. To show a detailed overview of cogenital and acquired diseases demonstrated by CT, MR, and/or angiography. To discuss the importance of careful analysis during the imaging interpretation. To discuss the prognosis of patients with these abnormalities. Background: Anomalies of superior and inferior vena cava are not rare. These abnormalities include congenital and acquired abnormalities associated with abnormal development, thrombosis, tumor, infl ammation, etc. Procedure Details: We provide a pictorial review of the embryology and anatomy of the superior and inferior vena cava. We show a detailed overview of congenital and acquired diseases demonstrated by CT, MR, and/or conventional angiography. We also discuss the importance of careful analysis during the imaging interpretation and the prognosis of patients with these abnormalities. Conclusion: Knowledge of this exhibit may be useful for the diagnosis and prediction of prognosis of patients with abnormality of the superior and inferior vena cava.

Interruption or congenital stenosis of the inferior vena cava Z. Koc, L. Oguzkurt, S. Ulusan; Adana/TR (zaferkoc@superonline.com) Purpose: To present the prevalence, clinical, and imaging fi ndings of interruption or congenital stenotic lesions of the inferior vena cava (IVC), associated malformations, and their clinical relevance. Methods and Materials: Between March 2004 and March 2006, 7972 patients who had undergone consecutive routine abdominal multidetector row computed tomography were analysed for interruption or stenotic lesion of the IVC. Results: Prevalence of interruption (n = 8) or congenital stenosis (n = 4) of the IVC occurred in 12 (0.15%) of 7972 patients. Four patients with interruption and 4 patients with congenital stenosis of the IVC were symptomatic with DVT (n = 4), leg swelling (n = 4), leg pain (n = 2), lower extremity varices (n = 2), hepatic vein thrombosis (n = 1), and hematochezia (n = 1). All four of the asymptomatic patients were from the interruption group, and these patients had interrupted IVC with well-developed azygos/hemiazygos continuation. Eight symptomatic patients did not have a well-developed azygos/hemiazygos continuation, and drainage of lower extremity was mainly from collateral veins. Additional fi ndings in 8 symptomatic patients were abdominal venous collaterals (n = 8), venous aneurysm (n = 2), lower extremity varices (n = 2), varicocele (n = 2), and pelvic varices (n=1). Conclusion: Interruption or stenosis of the IVC are rare on routine abdominal CT examinations and may cause different clinical fi ndings depending on the variant drainage patterns or collaterals. Interrupted IVC is commonly asymptomatic if associated with well-developed azygos/hemiazygos continuation, whereas commonly symptomatic if well-developed azygos/hemiazygos continuation is not present.