key: cord-0040045-bc258x9i
authors: nan
title: ESGAR 2008 - Book of Abstracts
date: 2008-06-05
journal: nan
DOI: 10.1007/s10406-008-0008-8
sha: 1307dc59a124be89a7774e11eb778ac94a0e95d8
doc_id: 40045
cord_uid: bc258x9i

nan

DOI: 10.1007/s10406-008-0008-8 well as arterial structures. CT cholangiography (CTC) images using minimum intensity projection techniques can be best obtained at the hepatic venous phase because of highest liver-to-duct contrast. Venous anatomy is also most clearly depicted in this phase. Various postprocessing techniques, such as multiplanar or curved reformations, maximum and minimum intensity projections, and volume rendering, are useful for demonstration of the primary tumor and its relationship with the surrounding structures. CTC using oral or intravenous administration of a biliary excreting agent may play a role in the evaluation of nonobstructed bile duct anatomy or diagnosis of choledocholithiasis, but its role in the evaluation of biliary malignancy is doubtful. CTC via biliary drainage catheter may be useful in cases where biliary decompression is already done. MDCT cholangiography is useful to demonstrate extraductal pathology and missing ducts that are difficult to assess on direct cholangiography. PET-CT scan is useful to depict unsuspected metastases, but the sensitivity for the diagnosis of the primary lesion is not better than MDCT. MDCT may be better than MRI with MRCP for depiction of vascular anatomy for its higher spatial resolution; however, the assessment of vascular invasion also depends on the delineation of the tissue plane between the vascular anatomy and the tumor, which may be better appreciated on the MRI because of its higher tissue contrast. Both MDCT and MRI may have limitations for defining longitudinal spread, especially when the tumor spreads along the mucosal plane instead of the periductal plane. Multiphasic MDCT combined with useful postprocessing techniques is helpful in improving diagnostic accuracy for the detection and preoperative staging of biliary malignancies but a multimodality approach is necessary for the interpretation of subtle abnormalities that are occasionally difficult to define even using a combination of all available imaging studies.

pancreatic carcinoma: detection and resectability J. Heiken; St. Louis, MO/US Learning objectives: To summarise MDCT scanning protocols used in detection and pre-operative assessment of pancreatic adenocarcinoma. To discuss the value of post-processing and the role of MDCT vis-à-vis state-of-the-art MRI. To review the pitfalls of MDCT evaluation. abstract: Purpose: To: 1) review the MDCT scanning protocols for detection and staging of pancreatic adenocarcinoma, 2) assess the value of image postprocessing in staging pancreatic cancer, 3) evaluate the role of MDCT versus MRI in detecting and staging pancreatic carcinoma, and 4) review the pitfalls of MDCT evaluation. Materials and Methods: Review published studies evaluating the optimal MDCT technique for imaging pancreatic cancer, and review published studies assessing the diagnostic performance of MDCT and MRI for the detection and staging of pancreatic adenocarcinoma. Results: MDCT is the preferred imaging method for detecting and staging pancreatic adenocarcinoma at most institutions. MDCT studies for assessing pancreatic cancer should be performed with narrow detector collimation, rapid intravenous contrast medium administration (e.g., 4 mL/sec), and dual phase imaging including both the pancreatic parenchymal and portal venous phases. Although most radiologists use a fixed scan delay of 40-50 seconds, accurate timing of the pancreatic parenchymal phase is best achieved using bolus tracking, with a scan delay of aortic transit time plus 20-30 seconds, depending upon the type of MDCT scanner being used. Accuracy of MDCT for determining nonresectability is approximately 95%, whereas accuracy for determining resectability is approximately 70-80%. Overall accuracy of MDCT for staging pancreatic carcinoma is approximately 80-90%. Review of CT angiographic images and multiplanar reconstructions improves assessment of vascular involvement compared with evaluation of transaxial images alone. Comparative studies have shown contrast enhanced MRI to be equivalent or superior to helical CT for detecting pancreatic cancer. However, recent comparisons between MDCT and state-of-the-art MRI are lacking. Limitations of MDCT include: 1) approximately 10% of pancreatic adenocarcinomas are isoattenuating to normal pancreatic parenchyma and may be very difficult to identify, 2) a number of benign abnormalities can mimic pancreatic cancer including focal pancreatitis and focal lipomatosis, 3) pancreatic cancer can be difficult to identify in patients with chronic pancreatitis, and 4) MDCT is limited in its ability to demonstrate small liver and peritoneal metastases. Conclusion: Although MDCT has some limitations and potential pitfalls, it is the preferred initial imaging method for detecting and staging pancreatic adenocarcinoma at most institutions. Proper contrast medium administration and scan timing are critical for optimal results. CT angiographic images and multiplanar reconstructions can improve staging accuracy. MRI is comparable to CT for detecting and staging pancreatic cancer and can be used when contrast enhanced MDCT is contraindicated. MRI is also useful for problem solving when MDCT evaluation is indeterminate.

Learning objectives: To describe the basic principles of CAD and discuss its role in current radiology practice. To outline the different types of CAD software currently on the market. To review the literature on the the clinical utility of CAD and try to predict its future prospects. abstract: Computer-assisted-detection (CAD) for CTC is increasingly commercially available, especially in Europe where regulatory stipulations have been satisfied. The current role of CAD is necessarily limited because systems are only just beginning to penetrate the market. A variety of different software packages are available, but all essentially do the same thing -they aim to detect colonic polyps and then alert the reader to their presence via a visual prompt, just as it happens in mammographic practice where CAD is well established. While this sounds simple and straightforward, in reality the scenario is complex: CAD seems to have a different effect on the ultimate diagnosis ascribed to the patient depending on when it is initiated by the reader. For example, if CAD is activated from the outset (the "first-reader" paradigm), the human observer may pay undue attention to the prompts and neglect the apparently normal colon. Because no CAD system is 100% sensitive, this may result in missed lesions. At the same time, no CAD is 100% specific -all systems make false-positive diagnoses and the effect that these have on ultimate diagnosis is also uncertain. Perhaps the major difference between commercially available systems (apart from price!) is the individual balance adopted between sensitivity and specificity. These two parameters are inextricably linked -for any given system sensitivity can only increase at the expense of specificity, and vice-versa. The different reading paradigms (first-, second-, and concurrent-readers) will be discussed. A major barrier to our understanding of the real effects of CAD in clinical practice is the fact that most research studies have determined the performance characteristics of CAD in isolation, assuming that the observer will react accordingly to prompts. In reality, there is no guarantee that an observer will classify prompts appropriately. What is needed are studies whose outcome measures revolve around the effect that CAD exerts on patient classification by the reader. Thankfully, such studies are becoming more common and it is already clear that human observers often misclassify true-positive CAD prompts as false-positive and vice-versa, diminishing the expected performance metrics. More studies of increasing complexity are needed in order to provide data for clarification but sensible and appropriate statistical analysis of such studies is exceedingly complex and at the cutting-edge of statistical methodology. Inevitably, these problems will be overcome and it is highly likely that ultimately CAD will become integrated into everyday clinical practice.

Higher resolution with contrast-enhanced Us and volume imaging for pancreatic tumours M. D'Onofrio; Verona/IT Ultrasound (US) examination is a simple imaging method considered in the workup of pancreatic lesions in numerous reference institutions for abdominal pathologies. Very often, US examination is the first imaging method used. The main advantage of US is the real time examination and the high contrast and spatial resolution of the state of the art technology. Moreover, US examinations enable the possibility of accurate flow analysis of the peri-pancreatic vessels at Doppler studies. Contrast-enhanced ultrasound (CEUS) has been revolutionized by the development of micro bubble contrast agents. The study of the pancreas is a relatively new application of CEUS. CEUS is different from dynamic CT and MRI in terms of technology and contrast media. In particular, CEUS is the only imaging technique which allows a continuous observation of the contrastenhanced phases, making the identification of fast flow tumoral circulation easier. The high temporal resolution of CEUS is one of the most important characteristics of this new imaging modality. The enhancement of a pancreatic lesion can be followed up during the whole study. Contrast-specific harmonic softwares allow maximum contrast resolution during CEUS studies. Moreover, nowadays, the spatial resolution of US imaging is very high also once detailed contrastenhanced images are obtainable. These typical features of this imaging method make CEUS very accurate in perfusional studies. Microbubbles are "blood pool" contrast agents so that CEUS images of pancreatic tumoral vessels (macrocirculation and microcirculation) are reported to have a very good correlation with the pathologic mean vascular density. Volume ultrasound imaging (VUI) is a relatively new technique based on the acquisition of volume dataset of anatomical structures. VUI has been changed by the introduction of automated 3D sweep acquisitions. Automated VUI allows overcoming the low reproducibility of the previous volume freehand sweep acquisition. Automated VUI allows introducing in the field of US the extremely important concept of reproducibility thanks to the possibility of a standardised and objective acquisition during the study.

Implementation of computer-aided detection into clinical practice P.J. Pickhardt; Madison, WI/US Computer-aided detection (CAD) will likely play an important role in CT colonography (CTC) interpretation in clinical practice. However, there are a number of challenges and unanswered questions with regard to implementing CAD into a large-volume CTC screening practice. The main potential benefit of incorporating CAD is to increase the sensitivity for lesion detection among less inexperienced or less skilled readers. However, depending upon how CAD is actually employed in the screening setting, this increase in sensitivity may be offset by decreased specificity and increased interpretation time. Instead of simply trying to maximize lesion detection rates and limit the number of false positive "hits", CAD systems should go one step further by assigning priority scores or confidence levels for suspected abnormalities rather than an unsorted list of polyp candidates. Additional challenges for CAD in clinical practice that will be discussed include the ability to handle cases with oral contrast tagging, deriving automated polyp measurements (including volumetry), and issues related to cost and reimbursement.

Colon Cad in reduced laxative CtC: does it work? P. Lefere; Roeselare/BE The possibility to reduce cathartic cleansing in virtual CT Colonoscopy (CTC) is one of the major opportunities as well as challenges in CTC. Reduced laxative CTC applies fecal tagging to opacify residual materials (ftCTC). The presence of opacified materials complicates matters for radiologists performing the examination and for scientists struggling with the problems of CAD in ftCTC. Besides the difficulties in characterisation, radiologists are confronted with increased difficulties in detection. The presence of tagged fecal material may reduce the conspicuity of both sessile and pedunculated polyps. Flat lesions and constricting cancers may be covered by tagged material, possibly improving but sometimes reducing conspicuity. ftCTC introduces challenges to CAD. Polyps submerged in tagged materials can be CAD false-negative (FN), and partially tagged semi-solid stool can be CAD false-positive (FP). Polyps affected by pseudo-enhancement, due to the presence of adjacent tagged material, can be identified incorrectly as tagged materials and thus missed by CAD. The following questions will be addressed: For the CAD software: 1/ What is the influence of ftCTC on the number of CAD FPs and FNs? 2/ Can we improve the accuracy of CAD by changing the sphericity or applying the adaptive density correction and density mapping? For radiologists: 1/ How does CAD in ftCTC influence the reading time? 2/ Does ftCTC affect the optimal reader paradigm of CAD? The term "double contrast MRI" does not only refer to the contemporary use of two different contrast agents (intravenous paramagnetic and oral superparamagnetic) for bowel evaluation, this term is also used to outline the white-and-black (or "double contrast") effect that can be obtained, on both T1 and T2-weighted images, by using this specific contrast association. Superparamagnetic (SPIO) oral contrast agents produce -in other terms -a very dark lumen effect both on T1 and T2-weighted images. This effect, if properly associated with fat-suppressed sequences and Gadolinium i.v. injection, outlines the bowel wall oedema (on T2-weighted fat-suppressed images) and wall hypervascularity (on post-Gadolinium T1-weighted images) in inflammatory bowel diseases (IBD), more than any other contrast agent association. In particular, SPIO oral contrast agents, if associated with fat-suppressed T2weighted sequences, allow visualizing the intestinal wall oedema and perivisceral fluid in IBD, not otherwise detectable. Bowel wall oedema and wall hypervascularity are both sensitive parameters of disease activity. Moreover, the negative contrast produced by the superparamagnetic oral agent determines a very homogeneous dark lumen effect throughout the small and large intestines, since the intestinal air and the intestinal agent add their signal on both T1 and T2-weighted sequences, differently from biphasic contrast agents. This allows an accurate evaluation the main intestinal abnormalities of IBDs, including the diagnosis of lesion's site and length, of strictures, adhesions, abscesses and fistulas, particularly in Crohn's disease. The main MRI patterns of mural and transmural wall inflammation in Crohn's disease and ulcerative colitis, as well intestinal and extraintestinal complications, will be shown. The clinical impact of this MRI technique in the evaluation of IBD will be finally discussed.

dynamic mrI of the liver R. Hammerstingl; Frankfurt/DE Over the past few years, magnetic resonance imaging (MRI) of the liver has progressed significantly. Technical advances in hardware and software have allowed the acquisition of images with excellent anatomic detail, largely free of artifacts secondary to respiratory motion. Contrast-enhanced MRI has become an essential part of a liver examination in a number of circumstances. Extracellular fluid space contrast agents are safe compounds in handling and provide information on vascularization and perfusion of focal liver tumors. A dynamic contrast-enhanced study of the liver is performed with a timing scheme that enables selective imaging during the arterial phase, the portal venous-phase, and the delayed phase of enhancement, the equilibrium phase. Fast spoiled gradient echo technique allows thin-section imaging of the entire liver during a single breath-hold. New volumetric sequences have enabled 3D serial dynamic imaging of the liver with a very high spatial and temporal resolution. The key issue of contrast agents in hepatic imaging is to discriminate between tissues that cannot be adequately differentiated on unenhanced MRI. Excellent contrast is needed for two purposes: delineation of at least one malignant lesion or exclusion of malignancy in the liver as well as precise characterization of benign liver tumors. For the detection of focal liver lesions, MRI using breath-hold sequences has been shown to be equivalent or even better than dual-phase CT. Particularly, hypervascular liver tumors show high contrast uptake in the early B 13 postgraduate Course

Lunch symposia scientific sessions epos™ presentations authors' index DOI: 10 .1007/s10406-008-0008-8 dynamic imaging, the arterial phase, whereas the surrounding cirrhotic liver tissue remains free of contrast agent. Information on morphology is fundamental for accurate characterization of focal liver lesions. Different characteristic features of the intravascular and extracellular spaces of the various focal liver lesions are depicted by extracellular gadolinium contrast agents. Dynamic imaging has also been shown to improve not only the distinction of malignant lesions but also to achieve the specific diagnosis for most liver tumors and to identify benign disease precisely. In addition to identifying the presence, number and type of focal lesions and the possible involvement of vascular and biliary structures, it is necessary to provide as much useful information on morphology and functionality as possible for therapeutic planning. Permeability imaging using computer assisted software solutions provides information for visualizing morphological changes and shows efficient assessment of dynamic MRI in liver tumors. It enables an adequate review of patient studies over time. Moreover, it permits easy comparison of parametric angiogenesis maps over time. Perfusionweighted MRI allows detecting intranodular hemodynamic characteristics in different liver tumors. The time to peak, maximal relative signal enhancement, and the initial slope of signal intensity vs. time curves of the tumors and surrounding liver tissue are to be evaluated. In addition, perfusion parameters of the Gd-chelate are to be measured. Pretreatment imaging is an important and necessary step for the assessment and therapeutic planning of patients with liver disease. In this regard, dynamic contrast-enhanced MRI has an important role in diagnosing the nature of liver tumors.

The most important issues in pancreatic imaging are the assessment of pancreatitis, the detection and staging of pancreatic cancer and the characterization of cystic lesions. 1.5-3.0 T MR make breath-hold imaging possible, in order to avoid motion artifacts. Standard imaging sequences are T1w GRE with and without fat saturation (which offer a very high tumor-pancreas contrast). T2-weighted imaging axial single-shot TSE with fatsat allow delineation of the pancreatic duct and peripancreatic edema in pancreatitis. MRCP pulse sequences and dynamic gadolinium-enhanced T1-weighted GRE images (preferably with fatsat) are mandatory in pancreatic imaging. They are helpful to delineate vessel infiltration by cancer and to characterize cystic masses. In case of an equivocal pancreatic mass, the presence of the "duct penetrating sign" at MRCP (i.e., the duct traversing the mass) is suggestive of an inflammatory pseudotumor. Focal fatty infiltration may mimic a tumor at CT, but in-and opposed phased T1w GRE readily depicts the fat. MDCT imaging has gained increasing popularity for pancreatic imaging because of the 3D-visualization of the peripancreatic vessels. MRI is excellent in the delineation of small pancreatic tumors. Due to its superior soft tissue contrast, MRI is also the method of choice in patients with suspected cancer and equivocal CT or compromised renal function. MRI is the technique of choice to characterize cystic lesions.

Lunch Symposium 5 pre-and postoperative liver imaging -the essentials Sponsored by: AGFA

Liver anatomy: segments and perihepatic space R. Manfredi; Verona/IT The internal lobation and segmentation of the liver is defined by the branching pattern of the structures entering and leaving its porta, with the hepatic veins coursing in the interlobar and intersegmental planes. This subdivision subdivides the liver into two lobes and eight segments, according to the Couinaid classification. At the hepatic porta, the portal vein divides into right and left portal vein branches, the proper hepatic artery divides into right and left hepatic arteries, and the common hepatic duct is formed by the junction of the right and left hepatic ducts. The right lobe of the liver is supplied or drained by the right branches of each of these structures. Likewise, the left hepatic lobe is supplied or drained by the left branches of each of these structures. Because the portal veins are the largest and most easily imaged intrahepatic structures, they are used to identify the hepatic lobes, segments, and sub-segments. The hepatic segments are further subdivided by the intrahepatic branches of the left and right portal veins. The liver has unique peritoneal and mesenteric relationships, which cause the upper portion of the greater peritoneal sac to be subdivided into four perihepatic recesses or spaces such as the falciform ligament, the coronary ligament, the right and left subphrenic or suprahepatic recess, hepato-renal space (Morrison's pouch) , and the left subhepatic recess. The common hepatic artery, in the classical pattern, arises from the celiac artery; this configuration occurs in 55% of the population. The common hepatic artery gives off the gastroduodenal artery, which descends behind the first part of the duodenum. After the emergence of the gastro-duodenal artery, the common hepatic artery changes its name becoming the proper hepatic artery. The portal vein forms behind the pancreatic neck by the confluence of the splenic and superior mesenteric vein.

Liver volumetry: what the radiologist should know T. Frauenfelder, B. Marincek; Zurich/CH In order to overcome shortage of liver donors, living related liver donor transplantation as well as tissue sparing liver surgery have been established as alternative methods. For both surgical approaches, liver volumetry has become indispensable. Liver volumetry is used to estimate liver (-segment) and tumor size. This information provides a decision guidance regarding surgical strategies and preoperative interventions (chemoembolisation, occlusion of portal branch). The base of liver volumetry is a semiautomatic segmentation of liver contours on cross-section images using dedicated software. The resulting volume depends on a variety of factors, such as slice thickness, type of segmentation or imaging modality influence. In order to achieve an optimal patient outcome, liver volumetry has to be performed in close cooperation with the surgeon. The future development of preoperative 3D-simulation techniques for hepatic interventions including liver volumetry will facilitate the surgical strategy. Liver volumetry is an important preoperative planning tool for liver surgery, influencing surgical strategies and decisions. It therefore bears a great responsibility for the radiologist. The learning objectives are: (1) To describe the technique of liver volumetry;

(2) To define the role of liver volumetry in clinical context; (3) To learn the limitations; (4) To outline future perspectives.

Vascular and biliary complications after liver surgery: imaging spectrum P. Boraschi; Pisa/IT Hepatic resection for malignant liver disease and liver transplantation for endstage chronic liver disease, as well as for severe acute liver failure, offer the possibility of long-term cure. Imaging techniques used for post-operative workup of patients with hepato-biliary surgery and/or liver transplantation mainly aim to identify vascular and biliary complications. A review of the literature regarding the results of post-operative complications after hepato-biliary surgery and/or liver transplantation is shown. Furthermore, the own experience on postoperative diagnostic work-up of these patients is presented. Despite the improvement and refinement of surgical techniques, the advances in organ preservation and improved immunosuppressive therapy agents, there are still significant complications after hepatic resection and/or liver transplantation. The role of imaging methods and particularly of CT and MRI consists of identifying post-operative complications, mainly including biliary strictures, stones and leakage, arterial and venous stenosis and thrombosis. The early recognition and prompt treatment of such complications improves the long-term survival of the patient and graft. Vascular and biliary complications after hepato-biliary surgery and/or liver transplantation are serious and are associated with a significant risk of morbidity and mortality. Because the clinical presentation of these patients may be subtle, imaging is extremely important in assessing and managing such complications. Knowledge and early recognition of these complications with the most suitable imaging modality is crucial for the patient.

Purpose: Gd-EOB-DTPA (Primovist) is a new liver-specific contrast agent for detection and characterisation of focal liver disease. The aim of the lecture is to introduce the current status of knowledge about MRI with Gd-EOB-DTPA. Materials and Methods: Based on the literature and on the own experience, the value of Gd-EOB-DTPA-enhanced MRI is evaluated with special regard to the use of Gd-EOB-DTPA as a pre-operative "one-stop-shop" examination. Results: Due to the dual pathway of excretion and, therefore, the extracellular and hepatobiliary imaging properties, Gd-EOB-DTPA-enhanced MRI can answer the usual questions arising prior to liver surgery: Where? What? How many? Also, additional questions about the liver vasculature and biliary anatomy can be addressed. In the future, even issues like liver function and prediction of the functional capacity of the remaining liver prior to resection might be resolved with the help of Gd-EOB-DTPA-enhanced MRI. Conclusion: Gd-EOB-DTPA is a versatile and safe MR contrast agent. Its imaging properties make it an ideal contrast agent for the investigation of patients with focal liver lesions, especially when liver surgery or interventional therapies are planned. CT colonography (CTC) is rapidly disseminating into routine clinical practice and is generally regarded a safe, accurate and frequently cheaper alternative to conventional colonoscopy. Consequently, and in parallel with promotion of national bowel cancer screening programmes, demand for CTC is increasing. Although generally welcome, such demand exerts additional pressure on radiology departments already experiencing intense competition for finite CT resources. In addition, CTC requires considerable investment in training and reporting time, placing it beyond the scope of many general radiologists, and attracting non-radiologists with a subspecialty interest in the diagnosis of colorectal cancer; the American Gastroenterology Association has declared that CTC, being a technique for investigating the colon, should be controlled by gastroenterologists. This symposium tackles the controversial subject of whether non-radiologists (radiographers and gastroenterologists) should report CTC and whether this activity can be safely and accurately undertaken. In support, emerging data suggests non-radiologists can potentially report CTC as accurately as experienced radiologists but issues related to extra-colonic findings, IRMER regulations and medico-legal implications of misdiagnosis are worthy of vigorous debate. E-Z-EM have gathered together an eminent group of entertaining European speakers with a wealth of CTC experience to debate this topic, which promises to engage members of the audience by inviting their opinions and contributions to a final vote.

A US examination of the liver remains the first line investigation for patients with an abnormality attributable to the hepatobiliary system. US is cost-effective particularly if the examination precludes the need to proceed to further imaging with CT and MRI. With the advent of microbubble US contrast, the need to extend the investigative algorithm diminishes markedly with obvious cost benefits. This is particularly noticeable with characterization of the incidental benign focal liver lesion; the atypical haemangioma, areas of focal fatty sparing or focal steatosis where confidence in the findings is rapidly established. In the cirrhotic patient, microbubble contrast allows for the characterization of doubtful lesions; the typical HCC demonstrating intense enhancement in the early arterial phase allowing for differentiation from regenerative nodules. With the follow-up of patients with a known primary malignancy, any focal lesion identified may be accurately characterized; malignant lesions always demonstrate washout on the late portal-venous phase. Following detection of the metastatic liver lesion, percutaneous treatment is now widely available; instantaneous assessment of the success of treatment can be improved with the use of microbubble contrast to assess the extent of successful ablation. When liver transplantation is the only effective treatment for end-stage liver disease, the post-operative assessment of the vascular supply to the graft is markedly improved with the addition of microbubble contrast. "Doppler rescue" is particularly useful in the assessment of the patency of the hepatic artery, crucial to the viability of the transplant liver. The use of microbubble contrast in many areas of liver US is cost-effective but more importantly improves operator confidence immeasurably. The use of bowel preparation is relatively contraindicated in elderly patients with multiple co-morbidities. There are reports of fatalities secondary to electrolyte and renal dysfunction and this has prompted caution in the use of such bowel preparations. Our aim is to evaluate the metabolic safety of full mechanical bowel preparation in a subgroup of elderly patients undergoing elective CTC. material and methods: From a total of 613 CT Colonography (CTC) examinations performed at our centre between January 2005 and December 2006, a subgroup of 75 elderly patients (mean age=80.1) who were admitted electively for full bowel preparation and IV rehydration prior to CTC were evaluated. The bowel preparation administered was 40 mg of Sodium Picosulphate Magnesium Citrate (PSMC) over a 3 day period. Haematological and biochemical parameters were recorded 3 days prior and 1 day post CTC and patients' medical records reviewed to assess for post procedural complications. results: There were mild electrolyte disturbances among the group periexamination. The average change in serum Na was +0.2851 mmol\L (range -6 to +8mmol\L). Importantly, changes in serum Na did not exceed 2 mmol/day in any members of the group. Renal function tests deteriorated in 24 patients peri CTC. The average rise in serum urea and creatinine was also mild at 0.125 mmol\L and 10 umol\L, respectively. Renal function objectively improved in 23 patients. Conclusion: Full mechanical bowel preparation is metabolically safe in elderly patients who are electively admitted for electrolyte monitoring and IV rehydration prior to CTC.

Virtual colonoscopy: development and validation of a new patient questionnaire for assessment of experience and compliance for bowel preparation P. Das, P. Wylie, R. Ahmad, M. Marshall, D. Burling; Harrow/UK purpose: Superior patient experience related to reduced laxative regimens is frequently cited as a major benefit of virtual colonoscopy (VC) but most related questionnaires are not valid or designed for endoscopy. We aimed to validate a new questionnaire for VC. material and methods: A 34 item questionnaire was created using expert opinion (including 2 VC researchers with relevant questionnaire-based publications), literature review and patient interview. 25 consecutive patients undergoing VC in routine practice (21 (84%) had sodium picosulphate/4 had senna 26 g and 100 mls gastrografin) were interviewed before their examination 'face-to-face' using the questionnaire. A series of open and closed questions related to ethnicity/understanding/convenience/tolerability/discomfort/anxiety/ compliance were asked. Responses were evaluated for content validity (frequency of similar responses) and following statistical advice, reliability was assessed by Spearman's correlation (inter-item correlation) and Cronbach's alpha (test of overall questionnaire reliability/consistency). results: 25 patients (13 (52%) female; median age 70 years) undergoing VC completed the questionnaires. 22 patients (88%) were either very satisfied (32%) or fairly satisfied (56%) with the bowel preparation. 27 questions were deemed valid in content and frequency of endorsement. There was good inter-item correlation (Spearman's p=-0.395-0.795) with a high level of reliability (Cronbach's alpha=0.904) overall. Conclusion: This questionnaire, developed for comparing VC bowel preparation regimens, is both valid and reliable and will be made freely available for use by ESGAR members. sCIentIFIC sessIons / Wednesday, JUne 11, 2008 B 18 DOI: 10.1007/s10406-008-0008-8 experienced observers. Reference standard was colonoscopy with segmental unblinding. Per patient sensitivity and specificity were calculated for both observers ('double reading') with two cut-off points using CTC matching criteria: lesions ≥10 mm (category 1) and lesions ≥6 mm (category 2). Positive and negative predictive values (PPV and NPV) were calculated using the CTC measured size as cut-off for triage. results: 15 FOBT positive patients had a carcinoma; CTC sensitivity 93%. Of FOBT positives, 50% had a category 1 lesion and 70% a category 2 lesion. Per patient sensitivity for CTC was 96% (95% CI: 92-100%) and 94% (95% CI: 90-99%) in categories 1 and 2, respectively. The per patient specificity was 93% (95% CI: 88-98%) and 80% (95% CI: 72-88%) for categories 1 and 2, respectively. Regarding CTC as triage method, PPV was 88% (95% CI: 82-95%) and 88% (95% CI: 81-94%) and NPV 85% (95% CI: 78-92%) and 78% (95% CI: 70-86%) for categories 1 and 2, respectively. Conclusion: CTC with limited bowel preparation is an accurate technique for carcinoma and polyp detection in a FOBT positive population. The use of CTC as cost effective triage technique is questionable given the high true positive FOBT rate.

CtC in colorectal cancer screening P. Della Monica on behalf of the IMPACT Study Group; Candiolo/IT purpose: The aim of the study was to optimize CTC management for colorectal cancer (CRC) screening. material and methods: A collated archive of CTC findings in 934 subjects at high risk of CRC for personal or family history (mean age + SD 57.7+9 y; 422 F) was analysed. Data were part of IMPACT trial comparing CTC to OC (Regge et al, RSNA 2008) . Neoplasia (advanced adenoma ≥ 6 mm) was in 174 patients (disease prevalence 19%), in 132 cases lesion was ≥ 10 mm (advanced neoplasia). CTC output was considered to be the diameter of the biggest lesion as measured on 2D multi-planar images. The cut-off value discriminating positive and negative CTC results was progressively increased in steps of 1 mm. Positive and negative predictive values (PPV, NPV) were calculated at each step. results: For CTC, cut-off progressively increased from 6 to 10 mm, PPV varied from 39 to 78% (from 50 to 74% for advanced neoplasia), NPV from 96 to 91%. Referral rate to optical colonoscopy varied from 26 to 15%. Optimum scenario was at 8 mm cut-off: PPV was 71% (62% for advanced neoplasia), NPV 94%, referral rate 20%. Conclusion: CTC is a very promising test for CRC screening. CTC cut-off value to activate optical colonoscopy can be tailored to optimise the screening programme.

a randomised comparison of CtC versus colonoscopy or barium enema for detection of colorectal cancer in symptomatic patients: the UK sIGGar study S. Halligan on behalf of the UK SIGGAR investigators; London/UK purpose: The potential role of CT colonography (CTC) for colorectal screening has been stressed repeatedly but CTC also shows great promise for the diagnosis of established cancer in symptomatic patients, possibly preferable to standard alternatives. The SIGGAR trial is a randomised controlled study of CTC versus colonoscopy or barium enema via two parallel sub-trials and is the only randomised study of CTC. This presentation is the first international presentation of results. material and methods: Adult patients with symptoms suggesting colorectal cancer and judged clinically as needing a whole-colon examination by colonoscopy or barium enema (default) were subsequently randomised to default or CTC (ratio 2:1, default: CTC). Colonoscopy was performed by experienced practitioners and enema/CTC interpreted by trained radiologists. The primary outcome measures were detection rates for colorectal cancer and significant colorectal neoplasia, defined as colorectal polyps 1 cm or larger. Analysis was by multivariable logistic regression with randomised procedure as the primary explanatory variable. results: Interim analysis of the colonoscopy and enema sub-trials revealed a prevalence of abnormality of 12 and 4%, predicting respective sample sizes of 1,422 and 3,402 to achieve 80% power. 9,072 patients were registered and 5,438 ultimately randomised: 1,610 to the colonoscopy sub-trial (539 CTC; 1071 colonoscopy) and 3,828 to the enema sub-trial (1,283 CTC; 2,545 enema). Detection rates by each procedure for primary outcome measures will be presented orally. Conclusion: CTC may have utility for the diagnosis of symptomatic colorectal cancer.

small and diminutive polyps detected at screening CtC: a decision analysis for referral to colonoscopy F. Iafrate 1 , C. Hassan 1 , A. Stagnitti 1 , P.J. Pickhardt 2 , A. Pichi 1 , R. Ferrari 3 , A. Laghi 3 ; 1 Rome/IT, 2 Madison, WI/US, 3 Latina/IT purpose: To assess the clinical and economic impact of colonoscopic referral for small and diminutive polyps detected at CTC screening. material and methods: A decision analysis model was constructed incorporating the expected polyp distribution, advanced adenoma prevalence, colorectal cancer risk, CTC performance, and costs related to CRC screening and treatment. The model assumed that CRC risk was independent of advanced adenoma size. The number of diminutive (≤5 mm), small (6-9 mm), and large (≥10 mm) CTCdetected polyps needed to be removed to detect one advanced adenoma or prevent one CRC over a 10-year time horizon were calculated. results: The estimated 10-year CRC risk for unresected diminutive, small, and large polyps was 0.08, 0.7, and 15.8%. The number of diminutive, small, and large polyps needed to be removed to avoid leaving behind one advanced adenoma was 562, 71, and 2.5, respectively; 2,352, 297, and 10.7 polypectomies would be needed to prevent one CRC over 10 years. The incremental costeffectiveness ratio of removing all diminutive and small CTC-detected polyps was $464,407 and $59,015 per life-year gained. Conclusion: For diminutive polyps, the very low likelihood of advanced neoplasia and the high costs associated with polypectomy argue against colonoscopic referral, whereas removal of large CTC-detected polyps is highly effective. The yield of colonoscopic referral for small polyps is relatively low, and so CTC surveillance may be a reasonable management option.

Colorectal cancer screening by colonoscopy or CtC: qualitative data from semi-structured focus groups and thematic analysis C. Robinson, C. von Wagner, S. Halligan, W. Atkin, J. Wardle; London/UK purpose: It is widely believed by radiologists that CT colonography (CTC) is preferred by asymptomatic individuals for colorectal screening. We determined whether this is true by establishing the information needs and preferences of asymptomatic individuals via semistructured focus groups and thematic analysis. material and methods: 26 asymptomatic volunteers participated in one of 7 semi-structured focus groups, split by gender. Demographic information was collected. Structured topic-guide information about colorectal cancer, benefits of screening, physical characteristics of colonoscopy and CTC and their performance characteristics were introduced to participants in a step-wise fashion. Group discussion followed each section and participants noted their beliefs and preferences on a questionnaire before moving to the next topic. Transcripts of the interviews were made subsequently, questionnaire data collated, and a qualitative thematic analysis performed. results: On the basis of minimal initial information, most participants preferred CTC to colonoscopy (65 vs 11%), with 24% having no preference. However, by the end of the topic guide session, this finding was dramatically reversed, with 80% preferring colonoscopy and only 8% CTC. Thematic analysis revealed that this was due almost completely to participants' concerns about sensitivity, which was ranked the most desirable test attribute overall. Specificity and personal inconvenience/discomfort were rated less important by participants. Conclusion: Test sensitivity is rated highest by asymptomatic screens. The assumption that CTC dominates colonoscopy by virtue of its acceptability may be incorrect. Amsterdam/NL, 2 Nijmegen/NL purpose: To investigate if different methods of CT colonography (CTC) data analysis result in different outcomes on per patient sensitivity, specificity, positive and negative predictive value (PPV and NPV). material and methods: CTC examinations of 200 FOBT positive patients who had colonoscopy with segmental unblinding were evaluated. CTCs were examined by 2 experienced, independent observers and results were added ('double reading'). Per patient sensitivity, specificity, PPV and NPV for polyps ≥10 mm were calculated using 2 methods: 1. by using matching criteria (matching based on size (with 50% margin of error), morphology and segmental location) and 2. by using the CTC lesion size measurement as cut-off value for colonoscopy indication. Significant differences were calculated using the Chi square test. results: 136 polyps of ≥10 mm were found in 99 patients. The sensitivity was 96% for method 1 and 84% for method 2 (p<0.05). The specificity was 89 and 93% (p>0.05) for methods 1 and 2, respectively. PVV was 93 and 88% (p>0.05) and NPV was 96 and 85% (p<0.05) for methods 1 and 2, respectively. Conclusion: Performing CTC data analysis by using the matching criteria commonly used in literature results in significant different outcomes for sensitivity and NPV compared to using CTC lesion size as cut-off value. This last method however would be applied in lesion size based triage for colonoscopy.

Focal liver lesions -multimodality approach

Hypervascular liver lesions on contrast-enhanced Us: the importance of washout D. Bhayana, T.K. Kim, H. Jang, P.N. Burns, S.R. Wilson; Toronto, ON/CA purpose: To evaluate the value of presence and timing of negative enhancement (washout) in the differential diagnosis of hypervascular liver lesions on contrastenhanced ultrasound (CEUS). material and methods: One-hundred fifty-three hypervascular liver lesions (1.0-17.0 cm, mean 3.89 cm) were evaluated with CEUS over a 6-month period. 81 were benign (34 hemangiomas, 33 FNH, 7 adenomas, 7 other) and 72 malignant (41 HCC, 25 metastases, 6 other). Two independent, blinded reviewers retrospectively determined timing of washout in the portal-venous phase, up to at least 4 minutes after injection of microbubbles (Definity). Diagnoses were confirmed by histopathology or clinicoradiological follow-up. Timing of washout was compared between different types of lesions using Fisher's exact test. results: Washout occurred in both benign (28/81, 35%) and malignant lesions (70/72, 97%), but more frequently in malignancy (P <.001) (κ=.94). Metastases showed more rapid washout than HCC (P <.001); 20/25 metastases by 30 seconds, and 23/41 HCC later than 75 seconds. All malignant lesions without washout were HCC (2/41). Among benign lesions, all 5 inflammatory lesions showed rapid washout and 6/7 adenomas showed washout, mostly later than 75 seconds (5/6). Unexpected washout also occurred in hemangiomas (6/34) and FNH (10/33). Conclusion: Malignant lesions show washout, except infrequent cases of HCC. Rapid washout characterizes metastases whereas HCC show variable, often slow washout. However, washout is not unique for malignancy and may be seen in benign lesions.

Quantification of wash-out of malignant liver lesions at contrast enhanced Us: usefulness of a semi-quantitative index in the differential diagnosis E. Gavazzi, P. Cabassa, E. Orlando, R. Monesi, E. Fogari, R. Maroldi; Brescia/IT purpose: Determine the efficacy of a semi-quantitative index in differential diagnosis of focal liver lesions during portal phase with contrast enhanced ultrasonography (CEUS). material and methods: 58 consecutive histologically proven malignant lesions studied with CEUS were retrospectively analysed. CEUS was performed with 2.4 ml of SonoVue with dedicated software (contrast coherent imaging). One significant frame (in bitmap format) of portal phase was chosen for each lesion and analysed by software (AdobePhotoshop 7.0). Two circular defined regions of interest (ROI) for each image were drawn encompassing the lesion and the adjacent normal parenchyma. Sonography videotape intensity (VI) was measured in gray-scale levels (0-255) through histogram analysis for each ROI. Background VI was set at the same level for each image. A semi-quantitative index (VItumor-VIliver/VIliver) was calculated. Results were divided according to histologic type and also compared with 15 benign lesions. results: HCC showed a median index value of -0.42, colangiocarcinomas of -0.62, metastases of -0.61 and benign lesions of 0.15. Well differentiated HCC showed a median index value of -0.09. Metastases were divided according to classical vascularization in hypo and hypervascular, the former showing a median index value of -0.65, the latter of -0.52.

We quantified hypoechogenicity of different focal liver lesions by a semi-quantitative index which can be useful in characterisation. In our series, CEUS correlates with pathology.

11:00 -12:30 topkapi a

High-resolution mrI offers an accurate method for predicting operability in oesophageal cancer A.M. Riddell 1 , G. Brown 1 , A.C. Wotherspoon 2 , Y. Barbachano 1 , C. Richardson 2 , W.H. Allum 2 ; 1 Sutton/UK, 2 London/UK purpose: The presence of a positive circumferential resection margin (CRM) is considered to confer a poor prognosis in patients with oesophageal cancer. The aim of this study was to establish whether high resolution MRI can accurately predict operability, based on achieving a negative CRM, and thus improve patient selection for surgery. material and methods: In this prospective study, 60 patients with biopsy proven adenocarcinoma, median age 64 yrs (range 43-81), M:F -7.5:1 underwent MRI using an external surface coil in addition to CT and endoscopic ultrasound (EUS) staging. Two radiologists independently reviewed the MRI studies blinded to results of conventional staging, surgery and pathology. MRI operability was predicted based on achieving a negative CRM. MRI prediction was compared with histopathology as the gold standard to establish the accuracy of the technique. MRI prediction was compared with EUS (McNemar's test). A positive CRM was defined as tumour at or within 1 mm of the CRM. The level of agreement between radiologists was determined using a kappa score. results: CT and EUS considered all patients bar 1 ‚borderline' case, as operable.

All resections were performed with curative intent. At laparotomy, 5/60 (8.3%) patients were inoperable, all predicted by MRI. 16/60 (27%) had an R1 resection. There were 4 false positive and 7 false negative predictions with MRI, giving a sensitivity, specificity and accuracy for predicting margin status of 67, 90 and 82%, respectively. The MRI accuracy was higher than EUS 67% (p=0.078). There was a good agreement between the radiologists for margin prediction: kappa score 0.7 (CI 0.51-0.89). Conclusion: High resolution MRI using an external surface coil offers an accurate, non-invasive method for predicting operability in patients with oesophageal cancer. Its use could help refine patient selection for surgical resection. Among them, 46 patients were diagnosed with recurrence of stomach cancer after curative resection but 38 patients had available preoperative information. All recurred cases were clinicopathologically confirmed. Their mean age was 62.3 year-old (range, 33-81) and male to female ratio was 31 to 8. We analyzed and correlated the recurred cases about primary location in stomach, post-op staging and gross and microscopic pathologies. We also evaluated the MDCT findings and medical records when the tumor recurrence had been diagnosed results: Location: cardia/fundus (3), body (8), antrum (21), or both (6). EGC (2), AGC (36). Well -(4), moderately -(14), or poorly differentiated/signet ring cell/ mucinous (14) and combined neuroendocrine differentiation (2). Staging: IA (2), IIB (5), II (4), IIIA (13), IIIB (15). Pattern: local recurrence (3), lymphatic -(17), hematogenos -(24), and peritoneal metastasis (17), more than one (16). Conclusion: More recurrence was noted in advanced gastric cancer, initially young age, histology of poorly differentiated or signet-ring cell type, and there is no difference of recurrence rate between the primary locations. material and methods: Five healthy volunteers and 14 patients with functional dyspepsia underwent MRI before and after 2 hours -30 minutes from a standardized meal (350 ml of water, 250 ml, 600 ml total). MRI was performed at 1.5 Tesla, on axial-coronal planes using T2-weighted HASTE (Half-Fourier SnapShot Turbo Spin-Echo) sequences. The fundic and overall gastric volume, the fundus/overall gastric volume ratio, the amount of gastric air before and after meal, the initial gastric volume were calculated; the gastric emptying curves and entero-colic variations of air-fluid content were assessed. results: In healthy volunteers, the mean residual volume and mean final fundic volume were 213 and 62.6 ml, whereas in dyspeptic patients they were, respectively, 251.4 and 82.5 ml. In pathologic patients, the mean fundus/stomach ratio was 0.46 before and 0.38 after the meal. In healthy volunteers, it was 0.75 before and 0.41 after the meal. In pathological subjects, the mean amount of gastric air before was 1.9 ml; in pathological subjects, it was 11.26 ml. In dyspeptic patient, the gastric emptying time at 2.5 hours was delayed in 2 patients (21-37%); in 12 it was within normal limits (57-70%). MRI data were correlated with clinical findings. Conclusion: Preliminarily, MRI seems a promising modality to assess gastric dysfunctions in dyspeptic patients.

evaluation of bowel motility by cine-mrI to detect bowel stenosis, adhesions or disturbances of peristalsis T. Heye, W. Hosch, G.W. Kauffmann, H.U. Kauczor, B. Radeleff; Heidelberg/DE purpose: Implementation of a cine-MRI sequence to enhance diagnostic performance of hydro-MRI studies to identify relevant stenosis or adhesions of the small/large bowel. material and methods: In this ongoing study, a total of 37 patients (median 45 yrs, age range 0-76, 14 m,23 f) were examined in a 1.5 Tesla MRI scanner by trufisp cine-MRI (10-12 slices, 10 measurements/slice, 7-10 mm slice thickness) to display real time bowel movement after oral intake of water and rectal filling with methyl cellulose. A standard hydro-MRI of the bowel was then added. 23 patients were referred for adhesions, 12 patients for inflammatory bowel disease, 1 patient for evaluation of a bowel stenosis and 1 patient for evaluation of bowel motility. results: 9 patients underwent surgery: in 6 patients with adhesions by MRI and relevant bowel obstruction surgery confirmed the diagnosis. 2 patients without adhesions by MRI underwent surgery for other reasons which showed no adhesions. In one patient, a relevant bowel stenosis was found by MRI and confirmed by surgery. In one patient, stenosis of bowel anastomosis was diagnosed by MRI and confirmed by fluoroscopy. 27 patients without findings by MRI were followed up without signs of bowel impairment so far. Conclusion: Dynamic cine-MRI of the bowel is beneficial by directly visualizing bowel motility to assess the functional relevance of a suspected bowel stenosis or impairment of bowel peristalsis.

Ct enteroclysis: role in diagnosis and management of low grade small bowel obstruction J. Nair, D.U. Kakde, V. Rathi; Nagpur/IN purpose: To demonstrate clinical feasibility and combined advantages of enteral challenge, cross sectional imaging and MDCT in the diagnosis and management of low grade small bowel obstruction (SBO). material and methods: Thirty patients with clinical suspicion of SBO were subjected to CT enteroclysis from September 2006 to September 2007. With informed consent, a 12 CH/FR Frekatube 120 cm gastroduodenal tube was positioned into the duodeno-jejunal junction under fluoroscopic guidance. Methyl cellulose preparation was infused @ of 150-200 ml/min. In all patients, CT enteroclysis was performed with dual slice helical CT scanner. Using 2 x 5 mm collimation, 120 kvp, 165 mA and 12.5 mm table speed, images were obtained.

1-2 ml IV buscopan was administered to the patient. Non-ionic contrast media was injected @ 2.5 ml/sec. Plain, arterial phase and venous phase (60 sec delay) images are obtained using 2 x 3 mm collimation. Soft tissue windows (WW=360 HU, WL= 40 HU) for viewing and 3D MPR reformation was done with thin 3 mm sections in spiral protocol. results: CT enteroclysis was well tolerated in all patients. Out of 30 patients, the order of occurrence of causes of SBO were adhesions 43%, strictures 27%, neoplasm 10%, vascular 7%, and others 13%. Conclusion: The combination of multiplanar reformatting, volume challenges of enteroclysis provides accurate assessment of overlapping loops making CT enteroclysis an important tool in the diagnosis and management of low grade SBO.

mdCt evaluation of the small bowel pathologies using oral administration of hypodence isotonic solution S. Mazzeo, V. Battaglia, C. Cappelli, F. Forasassi, L. Novaria, A. Belcari, C. Bartolozzi; Pisa/IT purpose: To assess the role of MDCT in the evaluation of small bowel in different pathologic conditions. material and methods: CT examinations of 106 patients with suspected/certain small bowel diseases were retrospectively analysed. CT protocol included oral administration of 2 L of polyethylene glycol solution and scans before and 50" after i.v contrast medium administration. Patients were divided into four groups: suspected/certain chronic inflammatory disease (A), suspected neoplastic lesion (B), malabsorption (C), aspecific abdominal pain, and occult bleeding or fever of unknown origin (D). Wall thickening, parietal contrast enhancement, valvular distribution, extraparietal involvement and abnormalities of the abdominal organs were analysed. CT findings were compared to clinical/laboratory findings, results of barium follow-through, ileo-colonoscopy findings and surgery. results: CT examination allowed a correct diagnosis in 86/106 cases; 20 patients were not included in the study because of inadequate bowel distention. At histopathology, patients resulted to be affected by: Crohn's disease of the small bowel (38), duodenal Crohn (1), granulomatous colitis (3), malabsorption (8), neoplastic lesion (4), post-actinic conglomeration of ileal loops (1), lymphangiectasia (1) and ulceration of the last ileal loop (1). CT showed a sensitivity, specificity and diagnostic accuracy of 91, 93 and 92%, respectively. Conclusion: MDCT of the small bowel represents a valid alternative to conventional radiographic studies and to small bowel methylcellulose enteroclysis spiral CT examinations.

Influence of temporal resolution on tumour perfusion Ct measurements: implications for helical perfusion Ct techniques V. Goh 1 , J.V. Liaw 1 , D. Wellsted 2 , S. Halligan 2 ; 1 Northwood/UK, 2 London/UK purpose: Helical perfusion CT techniques are being developed to enable a greater tumour volume to be assessed, yet scan temporal resolution achievable currently may preclude accurate measurement. Our purpose was to determine how scan temporal resolution influences ultimate colorectal cancer vascular parameters. material and methods: Following institutional review board approval, 45 patients with colorectal adenocarcinoma underwent a 65-second CT perfusion study: blood flow, volume and permeability surface area product were determined using commercial software based on distributed parameter analysis for three different temporal intervals between acquisitions (1, 2, 3 seconds, respectively). Mean blood flow, volume, and permeability surface area product measurements obtained for these three different intervals were compared using analysis of variance; statistical significance was at 5%. results: Mean (SD) for blood flow, volume and permeability surface area product were 71.5 ml/min/100g tissue, 6.33 ml/100g tissue, and 14.9 ml/min/100g tissue; 86.6 ml/min/100g tissue, 6.30 ml/100g tissue and 14.5 ml/min/100g tissue; and 97.8 ml/min/100g tissue, 5.98 ml/100g tissue and 14.5 ml/min/100g tissue for 1, 2 and 3 second intervals, respectively. Blood flow rose significantly as the temporal interval increased (p=0.008). Conclusion: Increasing the interval between acquisitions overestimates tumour blood flow, but not blood volume or permeability surface. Unless a temporal resolution better than 3 seconds can be achieved, helical perfusion CT techniques will inaccurately estimate blood flow.

The aim of this study was to determine the value of MR-colonic (MR-C) transit time in comparison to MR-defecography (MR-D) in patients suffering from chronic constipation. material and methods: 10 patients suffering from chronic constipation following "Rome II criteria" were examined using MR-visible markers for the assessment of the colonic transit time. In all patients, a dynamic MR-D examination was performed as well. For comparison reasons, 10 healthy volunteers also underwent the MR-transit time examination. The centreline for 20 CTCs (10 male) with adequate colonic distension was determined for both prone and supine studies using a workstation and the colon divided into five segments. The spatial co-ordinates of each segment were related to the SMA origin by triangulation and the degree and direction of displacement between prone/supine studies determined. results: Mean displacement of centerline points within individual colonic segments was 3.6 (0.7), 3.1 (0.3), 3.5 (1.1), 4.6 (0.5) and 3.7 (SD 0.7 cm) cm for men and 2.9 (0.4), 3.2 (0.7), 3.1 (0.8), 4.1 (0.4) and 3.7 (SD 0.5 cm) cm for women for rectum, sigmoid, descending, transverse and ascending segments, respectively. On change from supine to prone position, overall colonic displacement reflected anterior abdominal wall compression. Rectum and sigmoid preferentially moved posteriorly and to the patient's right and ascending, descending and transverse colonic segments preferentially moved posteriorly. Furthermore, a caudal displacement was found for sigmoid, transverse and ascending colonic segments. There was no significant difference in total colonic length between the prone and supine position for men (p=0.98) or women (p=0.87). Conclusion: Our findings suggest that when distended, colonic configuration change is small and dictated primarily by changes in abdominal compression rather than gravity.

CtC: who should read it? Z. Tarján, L. Lukács, N. Mészáros, J. Koloszár; Budapest/HU purpose: To evaluate if medical students using a CAD system could effectively read CTC. material and methods: Fifty colonoscopy controlled CTC data (with high lesion prevalency) were evaluated by 5th year medical students and a radiologist skilled in CTC reading. Five reading strategies were used: a) 2D reading, b) 2D reading with CAD prompts, c) 3D virtual endoscopy based reading, d) 3D with CAD prompt, and e) CAD read alone using an academic CAD system. The reading time and diagnostic accuracies of the different strategies were compared statistically by a Yates corrected chi square test. results: In detecting polyps and masses >5 mm, the radiologist using CAD prompts reached 0.93 and 0.7, medical students 0.85-0.89 and 5.2-6.3, while the CAD system alone 0.87 and 4.8 (sensitivity, false positive finding/case) (p>0.05). 2D reading by the radiologist with CAD prompts proved to be the fastest reading strategy (average 52+34 sec SD), while the students needed 267+123 sec SD for the same. Using 3D virtual endoscopy, the reading time was significantly longer (p<0.05), and yielded higher sensitivity, but less specificity (p>0.05) for all readers compared to 2D+CAD. Conclusion: CAD prompts bring the sensitivity of medical students close to that of a skilled radiologist in reading CTC data, but the CAD or students with CAD could not rule out false positives effectively.

Validating . Twenty-seven inexperienced radiologists (no CTC performed before the course) were involved in the study. The used dataset included 26 cases with different kind of lesions: 12 diminutive lesions (<6 mm), 12 medium size polyps (6-9 mm), 9 large polyps (>10 mm) and 6 masses (>3 cm). Participants had 20 minutes to assess each CTC dataset without CAD and then with CAD. They were asked to recognize the lesion, determine the morphology, size and location. results: The overall sensitivity for the detection of polyps of all sizes increased from 35 without CAD to 42% when using CAD (p-value<0.05). In particular, the sensitivity for the detection of small polyps moved from 18 to 27%, for medium size polyps from 33 to 36% and for large polyps from 60 to 68%. Conclusion: CAD increases the performance of inexperienced radiologists in detecting colorectal lesions of all sizes. The readers judged the use of CAD helpful as a self-assessment tool.

Computer aided detection in CtC: evaluation of benefit to the readers in a second reader paradigm P. Braude 1 , M. Zalcman 2 , S. The presence or absence of recurrence was proved by biopsy or follow-up imaging and were correlated with FDG PET/CT findings (the presence or absence of FDG uptake) by calculating the diagnostic values. FDG PET/CT findings were also compared with initial CT findings and histologic grades of HCCs. results: FDG uptake was present inside the liver in 11 patients and outside the liver in 6 patients, and all these patients proved to have intra-or extrahepatic recurrences. FDG uptake was absent in the remaining 27 patients, but 15 of these patients were proved to have recurrences. The sensitivity, specificity, positive predictive value and negative predictive value of FDG uptake for detecting recurrence were 53, 100, 100 and 44%, respectively. FDG uptake had no significant correlation with initial CT findings and histologic grades of HCCs. Conclusion: FDG PET/CT is highly specific and predictive in detecting HCC which is occult at CT for post-procedural patients particularly when tumor markers are elevated. Moreover, FDG PET/CT may be helpful in detecting distant metastasis. We examined a total of 30 female and 10 male volunteers (mean age 53, range 26-80 years). All the volunteers were examined first with defecography and then with a functional cine-MRI. Defecography was performed using a remote controlled device (Siemens); the patients were in a sitting position, opacification of rectum and vagina (in the female) was achieved by filling them with barium paste. The rapid sequence radiographs were reordered on videotape. Functional cine-MRI was performed with a 0.22 T magnet unit open configuration (Siemens, Concerto). Static images with T2-w sequences and dynamic images with T2-Breath-hold sequences were obtained during relaxation, maximal sphincter contraction and straining. The patient rectum was filled with sonography gel and Gd-DTPA. The images thus obtained were assembled in cine-view. results: Cine-MRI findings were: 21 anterior rectoceles, 4 rectorectal intussusception, 2 rectal prolapse , 5 cystoceles, 7 enteroceles, and 2 cervical/ vaginal vault prolapse. Defecography detected 19 anterior rectoceles, 7 rectorectal intussusceptions, 8 rectal prolapse, and 4 cystoceles.

The use of the fast sequences of the cine-MRI allows the morphologic study of the pelvic floor together with the dynamic evaluation of the pelvic organs with a more diagnostic accuracy and sensibility than the defecography in order to detect the different types of pelvic organ prolapse. sequence was acquired at rest, contraction and straining on sagittal planes and repeated in dynamic modality on the mid-sagittal plane two times, with no evacuation phase, in supine and lateral position. We adopted specific MRI modified values for rectoceles and ano-rectal descents, obtained by a control group of healthy volunteers. Gold standard was conventional defecography and/or surgery. results: MRI identified with both techniques 18 rectoceles (100%), 15/17 (88%) ano-rectal junction descents, 15/19 (79%) rectal invaginations, 2 dyskinetic pubo-rectal syndromes, 4 uterine descents, 5 cystoceles, 3 enteroceles. In 18/23 patients, the same results were obtained with both techniques, for all parameters; in 3/18 patients with rectocele and 3/5 with cystoceles, a slightly higher evidence of the disease was obtained in lateral positions. In 1/23 patients, pathologic findings were observed in lateral position only. Conclusion: Both supine and lateral positions, although non physiologic, allow MRI assessment of the majority of posterior pelvic floor disorders. Lateral position, however, allowed better evidence of rectoceles and cystoceles in our experience. Transanal-stapler-resection for treating obstructive defecatory disorders presents an innovative operation-technique. The aim of this study was to prospectively evaluate morphological and functional results after stapled transanal rectal resection (STARR)-surgery using dynamic MR-defecography. material and methods: Patients with obstructive defecation-dysfunction were interviewed pre-and postoperatively, also undergoing rectal-manometry, procto/ rectoscopy and MR-defecography. Slow-transit-patients with a defecation rate >1/week and patients with concomitant pelvic-floor-dyssynergy were excluded. All patients underwent a STARR-operation in general anaesthesia. The mean follow-up was 20±6 months. results: 10 patients (10 f, 0 m; 62±12 years) were enrolled with successful performance of the STARR-operation. Preoperatively all patients reported a fractionated defecation, only 6 patients (p=0.02) postoperatively. A subjective defecatory improvement was observed in 6 patients (p=0.02), 9 patients showed a preoperative intussusception, compared to only 3 patients (p=0.02) postoperatively. In MRI, 9/10 patients showed preoperative intussusception versus 1/10 patient potoperatively (p=0.002). The rectozele-size was assessed on MRI preoperatively with 2.6±1.4 cm versus postoperatively with 1.4±1.2 cm (p=0.05). In patients with additional MR-findings as cystocele a significant extentreduction was found comparing pre-with postoperative findings. During rectal manometry, the active pinch-pressure and the pressure-at-rest showed no significant difference pre versus postoperatively. Conclusion: Whereas in almost all patients an anatomic correction of intussusception was performed, only a few report functional improvement, comparable to alternative operation-methods. Examinations such as MRdefecography are necessary to identify those patients possibly benefiting the most from the STARR-operation.

Contrast 

Comparison of a standard and a weighted linear regression analysis method for the calculation of the apparent diffusion coefficient of the liver and spleen T.G. Maris, S. Gourtsoyianni, N. Papanikolaou, K. Karolemeas, S.D. Yarmenitis, N. Gourtsoyiannis; Heraklion/GR purpose: To compare two mathematical techniques for the calculation of apparent diffusion coefficient (ADC) of normal liver, liver focal lesions and normal spleen. material and methods: Forty-five consecutive patients underwent MRI examination of the liver and spleen, utilizing a spin-echo echo planar imaging diffusion sequence with four b-values (0, 50, 500, 1000). ADC calculated colour image maps were post-proccessingly reconstructed using: (a) a standard and (b) a weighted linear regression fitting model with b-values of 50, 500 and 1000. The two analytical methods (a and b) were compared in terms of their precision in the ADC calculations. results: Differences amongst all ADC values were considered significant (ANOVA, p<0.01) using either methods. Post-hoc pair wise comparisons showed a better discrimination between normal liver and focal liver lesions when using method (b) (p<0.01). ADC measurements performed with method (b) showed a better precision (mean CV=3.5%) as compared with method (a) (mean CV=8.3%). Bland-Altman plot showed a 4% increment of the mean ADC values when method (b) was used and a random statistical variation within the 95% confidence intervals indicating that both methods could be used interchangeably. Conclusion: ADC quantification of the liver and spleen may be performed with both standard and weighted linear regression analysis methods. However, the precision is significantly improved when weighted regression analysis methods are utilized.

Can diffusion weighted imaging be used to grade the severity of liver fibrosis and cirrhosis? K. Sandrasegaran, F. Akisik, A.M. Aisen, C. Lin; Indianapolis, IN/US purpose: To determine the correlation between apparent diffusion coefficient (ADC) of liver parenchyma and the grade of liver fibrosis determined by liver histology in patients with chronic liver disease. material and methods: 78 patients who had diffusion weighted imaging (DWI) using 1.5 T MRI (Magnetom Avanto, Siemens, Erlangen, Germany) and pathological staging of liver fibrosis were included for this study. DWI was performed with b values of 0 and 500 s/mm 2 . Apparent diffusion coefficients (ADC) of liver were measured in the right and left lobes of the liver. results: The mean (standard deviation) ADC values of liver fibrosis graded as 0 (n=11), 1 (n=16), 2 (n=10), 3 (n=14) and 4 (n=27) were 118.5 (22.7), 101.1 (16.6), 102.4 (20.4), 102.3 (16.6) and 99.1 (12.0) x10 -5 mm 2 /s, respectively. The correlation between the ADC values and degree of liver fibrosis was good (r=-0.77). There was a significant difference in ADC values between those with normal liver and cirrhosis (p=0.001). No significant difference was seen in ADC values between grades 1 and 2 combined versus grades 3 and 4 combined (p=0.71). The etiology of liver disease did not affect ADC. Conclusion: ADC in cirrhotic livers is significantly lower than in normal liver. ADC values decrease with increasing hepatic fibrosis. However, we were unable to reliably classify patients as having low or high degree of fibrosis using ADC values.

diffusion-weighted mrI for the assessment of liver fibrosis is just a matter of perfusion: a study using two single-shot spin echo echo-planar diffusion-weighted mrI sequences with increasing b-values R. Girometti 2). Every nodule enhancing during arterial phase with wash out at portal or late phase was considered malignant and studied with MDCT or MR. The CEUS impact was classified into 5 categories: no effect (A), benign focal liver lesions discovered (B), indeterminate lesion (C), single HCC(D); and bilateral HCCs (E). Variables like pseudonodular appearance and raised alfafetoprotein (AFP) levels were also analysed. results: The outcome of CEUS was A in 14 (41.2%), B in 9 (26.5%), C in 2 (5.9%), D in 4 (11.8%), E in 5 (14.7%). Therefore, patient management significantly changed (C-E) in 11/34 patients (32.6%). HCC detection was significant superior in patients with raised levels of AFP and in patients with pseudonodular appearance of liver echotexture (p<0.05). Conclusion: One third of patients changed management (C-E) following CEUS. Therefore, CEUS, from these preliminary experiences, could be proposed as useful tool in these patients. results: Hepatic vascular problems were diagnosed in 15 recipients (15%). Their total number was 17 (9 hepatic artery, 6 portal vein, and 2 hepatic venous outflow problems). Twelve (70.6%) of the reported vascular complications occurred within the first 4 weeks post-transplantation and the remaining 5 (29.4%) occurred beyond 4 weeks post-transplantation. There was no statistical significance between the group which developed vascular complications and the group that did not in the overall mortality rate, rate of rejection, number of biliary problems, recurrence of HCV hepatitis, incidence of systemic or graft sepsis. The Doppler US findings obtained from the hepatic vasculature were reliable for diagnosing the various posttransplantation vascular problems but non-diagnostic nor specific in the patients who developed other hepatic parenchymal problems. Conclusion: Doppler US is a reliable method in the diagnosis of hepatic vascular problems occurring in the post-transplantation setting but is less sensitive in diagnosing or in follow-up of other medical or surgical complications. To determine the indications and the procedure, and to evaluate technical results and the safety of insertion of metallic markers in the liver before radiofrequency ablation (RFA) in poorly visible tumors on CT-fluoroscopy. material and methods: From January 2003 to June 2007, 30 radio-opaque markers were inserted in liver lesions of 24 patients. These vascular platinum coils were inserted through an 18-gauge needle based on prior imaging modalities (CT and/or MRI) before the RFA procedure. After contrast enhanced CT-scan, we used those radio-opaque markers for guidance of the RFA procedure during CTfluoroscopy. Thirty-one tumours (17 HCC, 14 metastases poorly visible on unenhanced CT-scan) with mean size 2.3 cm (SD 1.1) were ablated. The outcome and complications were analyzed. results: The markers guided the RFA electrodes in all cases. The median followup time was 11.3 months (range 2-32 months). The technique effectiveness rate was 77.8%. There were no direct complications after marker insertion. We noted 4 minor complications (subcapsular hematomas) after RFA.

The described technique is easy to perform and safe. This technique enables accurate guidance of RFA in poorly visible lesions on CT-fluoroscopy.

percutaneous Ct-guided cryoablation of liver tumors: experience in 32 tumors S. Tatli, P.R. Morrison, K. Tuncali, S.G. Silverman; Boston, MA/US purpose: To report our experience with CT-guided percutaneous cryoablation of liver tumors. material and methods: Thirty-two tumors (range: 0.7-5.6 cm, mean diameter 2.7 cm) in 22 patients (12 F, 10 M; mean age 63 years, range 44-88) were treated (26 procedures; 33 total cryoablations). Of 32 tumors, 9 were hepatocellular carcinoma, and the remaining were metastases from various primaries. Using CT fluoroscopy, multiple (mean 3, range 1-7) cryoprobes were placed and intermittent CT monitoring was used to depict the growth of iceball and nearby organs. Procedures were performed under general (n=10) or monitored assisted (n=16) anesthesia. Adjacent structures were displaced away with percutaneously injected saline (n=3). All but two tumors were evaluated next day with enhanced MRI (n=29) or CT (n=1). Thirty tumors have been followed for 3 months or more (mean 6, range 3-12). Tumors were considered successfully ablated if they demonstrated no enhancement. results: Thirty-one (97%) of 32 tumors were successfully ablated. 31 (97%) tumors required only one treatment session. All patients but two were discharged the next day without complication. One patient developed pulmonary edema but recovered fully. An 88-year-old man experienced renal and respiratory failure the day after the procedure and died. Conclusion: Cryoablation can be used to treat liver tumors successfully. CT scan can be used to visualize the iceball and tumor to maximize the changes of treating the tumor completely, while avoiding complications.

analysis of the use of multiple, sequentially-activated, internally-cooled electrodes for radiofrequency ablation of hepatic metastases J. Taylor, W.R. Lees, A. Gillams; London/UK purpose: To report on the use of multiple, sequentially-activated, internallycooled radio-frequency electrodes in the treatment of hepatic metastases (HM). material and methods: Forty-five metastases in 26 patients, 17 male, mean age 62 years (39-82) were treated with 2 or 3 internally cooled electrodes sequentially and alternatingly activated via a switching controller (Covidien, Boulder, CO). Twenty-one patients had colorectal liver metastases, 2 breast, 2 neuroendocrine and 1 adrenal. The lesion size, location, number of electrodes, ablation zone size, completeness, complications, local recurrence, tract seeding and follow up imaging were recorded. results: Two electrodes were used in 26 lesions, mean diameter 2.8 cm, and 3 electrodes were used in 19 lesions, mean diameter 5.0 cm (p < 0.05). The mean ablation zone with 2 electrodes was 4.6 x 3.8 x 4 cm and with 3 electrodes was To evaluate liver primary and metastatic tumors radioembolization with yttrium (Y-90) in patients not responsive to chemotherapy. material and methods: In the last two years, we treated 110 patients suffering from liver primary or metastatic tumor. All patients arrived to our observation with disease progression, despite undergoing different major/minor surgical or microinvasive percutaneous procedures (RFA, PEI, etc.). Patients underwent a preliminary abdominal CT and a body PET. On treatment planning, we performed a gastro-duodenal artery coiling. At the end of procedure, we injected technetium (Tc-99m) aggregated albumin through the hepatic artery. We excluded from the treatment patients with bilirubin level greater than 1.8 mg and patients with pulmonary shunt over 20% but not patients with extra-hepatic metastases. On the day of treatment, under fluoroscopy guidance, we implanted a dose of Y-90 microspheres calculated on the basis of liver tumoral involvement and BSA formula. The patients were kept under observation for 18-24 hours and discharged the day after treatment. results: In all cases, we obtained a reduction and/or a normalization of tumoral markers in a period of between 4 and 8 weeks. PET showed a partial and/or total remission of liver metastases. A patient with bilirubin levels of 1.7 mg died of hepatic failure, 30 days after treatment. Two patients with hepatic involvement of over 60% died during follow-up. Conclusion: Y-90 spheres radioembolization is an effective and safe method for treating liver metastases with acceptable levels of complications and very high response rates.

analysis of the factors that impact 5-year survival following radiofrequency ablation of colorectal liver metastases A. Gillams, W.R. Lees; London/UK purpose: Radiofrequency ablation is increasingly accepted as a treatment option in patients with colorectal liver metastases (LM). We analysed the factors that impact 5-yr survival. material and methods: There were 309 patients, 198 male, mean age 64 years (24-92) treated at 617 treatment sessions. The standard protocol was treatment under general anaesthesia with internally water-cooled electrodes (Covidien, Boulder, CO) introduced percutaneously using US and CT guidance/monitoring. The number and size of metastases, presence and location of extra-hepatic disease, primary resection, clinical and follow-up data were recorded. Survival was calculated from the diagnosis of LM and from ablation. Univariate and multivariate analysis were performed using SPSS v.10. results: The mean number of LM was 4 (1-27) and the mean maximum diameter 3.7 cm (0.9-12 To assess with MRI the main morphological changes and complications of Crohn's disease in paediatric patients. material and methods: 40 patients, mean age 15 years (range 6-18), underwent MRI scan following the administration of super-paramagnetic oral contrast agent at variable doses, according to patient weight and compliance, using T2-weighted HASTE (half Fourier snapshot turbo spin echo), and T1-weighted FLASH (fast low angle shot) sequences, both with or without fat saturation (FS), before and after contrast agent (gadolinium) iv injection. Two radiologists independently evaluated localization and length of the lesions, complications (stenoses, abscesses and fistulas), and peri-anal localization of Crohn's disease. MRI results were compared with ileo-colonoscopy, barium upper GI series and intestinal US examinations. Sensitivity and accuracy were estimated. Results were also compared with data obtained from an adult population sample.

results: MRI accuracy in lesions localization in the small and large bowels was, respectively, 93 and 97%. MRI revealed 83% of stenoses, 100% of entero-enteric and peri-anal fistulas. The percentage of ileal localization was the same in children and adults, while colonic localization was more frequent in children (D: 40% To assess the accuracy of T2-weighted sequences in the evaluation of Crohn's disease. material and methods: Sixty-five patients with Crohn's disease underwent MRI, using T2-weighted HASTE (Half-Fourier SnapShot Turbo spin-Echo) sequences, with or without fat-saturation after oral administration of a superparamagnetic contrast agent, to optimize T2 bowel wall signal. For comparison, FLASH (Fast Low Angle Shot) T1-weighted sequences, with or without fat-suppression, before and after gadolinium injection were obtained. References examinations were: barium studies, ileocolonscopy, US and CT, and endoscopic index of severity (CDEIS). The data obtained with T2-sequences were evaluated independently from those obtained with T1-sequences, as for: -disease localization and length of lesions, from jejunum to rectum -presence of wall fibrosis, strictures and fistulas. results: T2 weighted MRI was 98% sensitive and 92% specific for detection of ileal lesions; 80% sensitive ,78% specific for jejunal lesions; 67 to 88% sensitive and 96 to 100% specific for colonic lesions, at different levels. Accuracy in detecting entero-enteric fistulas was 88%, non enteric fistulas 98%; all abscesses and phlegmons were diagnosed. T2-wall signal and T2-signal of the perivisceral fat were significantly related (p<0.001) to CDEIS and biological activity. Similar results were obtained for T1-weighted post-Gadolinium sequences. Conclusion: T2-weighted MRI can be used alone for the assessment of Crohn's disease.

assessment and clinical validation of colon motility using functional cine-mrI S. Kirchhoff, M. Nicolaus, J. Schirra, C. Kirchhoff, B. Göke, M.F. Reiser, A. Lienemann; Munich/DE purpose: GI functional disorders (constipation, stool-outlet-obstruction) are common symptoms. The diagnosis of functional motility-disorders especially of the colon is difficult due to non-existing adequate examination-techniques. Barostat and manometry are rarely used in routine due to duration and invasiveness. Colon-transit-time-, double-contrast-enema-examination provide only static information. Due to great soft-tissue contrast, missing ionizing radiation, MRI seems to be appropriate to depict morphology and function of the large bowel. Therefore, the aim of our study was to cholinergically stimulate the phasic colon motility under manometric control and to simultaneously identify the morphology with Cine-MRI. material and methods: During colonoscopy, a water-perfused-multi-luminalprobe is placed in the descending-colon, and intraluminal pressure-changes were marked over-time. After a 90-minute-equilibration-phase, an MR-exam-atrest (HASTE-sequence, 1.5 Tesla-Avanto®, Siemens-Medical-Solutions, Erlangen) was performed. Consecutively, bisacodyl (3 ml-and-10 ml-saline 0.9%) were instilled via the probe. Cine-MRI and manometry were performed simultaneously over 24 minutes. Manometry-data were analysed for high amplitude propagated contractions using PC-based software, and MRI-data were primarily analysed visually. results: 18 healthy volunteers (age: 19-62 years, 8 f, 10 m) were enrolled. In correlating MRI with manometry-data, manometry showed 13 HAPCs, 12 were identified in MRI. In addition, MRI showed 7 negative-colonic-peristaltic-waves (relaxation) without correlate in manometry.

In this feasibility study, we could show that Cine-MRI allows for a visualisation and quantification of HAPCs using an adequate stimulus. However, our first visual evaluation of MR-data needs to be supported by the results of semi-automatic software being the focus of current investigations. . material and methods: 20 patients who underwent liver surgery were preoperatively imaged with either a 64-slice MDCT-(n=10) or a 1.5 T MR-scanner (n=10). MDCT-and 3D-GRE MR-images were reconstructed with different ST (2, 4, 6 and 8 mm). The total liver volumes (TLV) were measured by two independent readers based on different ST using semiautomatic software. Results were compared to the TLVs obtained at 2 mm ST which served as standard of reference (SOR). The time needed for each volumetry was recorded. results: When using MDCT, a statistical difference was seen only between the volumes based on 2 vs 8 mm ST for both readers (p=.012/.002). When MRimaging was used for volumetry, there was no statistical difference between the volume of the SOR and the volumes based on thicker slices (4, 6 and 8 mm).

Regarding the time to perform volumetry, there was a significant gain of time for both readers when volumetry was performed on 6 and 8 mm MDCT-and on 4, 6 and 8 mm MR-slices (p<.0167) compared to the SOR. Conclusion: Accuracy of LV based on either MDCT-or MR-images is dependent on ST. With respect to accuracy of the calculated volume and the significant gain of time, 6 mm ST is preferable for CT-imaging and 8 mm ST for MR-imaging.

anatomic variations of the hepatic arteries in 250 patients studied with 64-row mdCt angiography C.N. de Cecco 1 , R. Ferrari 2 , P. Paolantonio 2 , M. Rengo 1 , F. Vecchietti 2 , A. Laghi 2 ; 1 Rome/IT, 2 Latina/IT purpose: To present the findings of 250 consecutive CT angiographies of the hepatic arteries and to compare them with data from literature obtained in other large 4-16 row CT series. material and methods: A total of 250 consecutive 64-row CT angiographies (CTA) obtained using a high resolution protocol were retrospectively evaluated. Arterial phase images were analyzed by two radiologists in consensus using different reconstruction algorithms and the anatomic findings were grouped according to Michels classification. Arterial variants not included in Michels classification were separately recorded. results: A normal arterial pattern was observed in 64.8% of the cases. The most common anomaly was Michels type III (9.6%), followed by types V and II (6.0 and 4.8%), type VI (3.6%), type VII (2.0%), types IV and IX (1.6%), and type VIII (1.2%). No cases of Michels type X were detected. Additional, previously unclassified variations were observed in 4.8% of the cases. Conclusion: 64-row CTA compared to previous work with 4-16 detectors permits to depict an higher number of accessory hepatic arteries, thanks to isotropic voxel, high resolution protocols and optimization of contrast administration. The visualization of these abnormalities may be a crucial point in programming operative procedures like liver transplantation, hepatic resections and chemoembolizations. This approach could probably permit a reduction in iatrogenic lesion.

Contrast enhancement with iomeprol-400 and iodixanol-320 in patients undergoing contrast-enhanced mdCt of the liver L. Grazioli 1 , C. Catalano 2 , L. Bonomo 2 , J. Xu 3 , K. Chen 3 , L. Romano 4 ; 1 Brescia/IT, 2 Rome/IT, 3 Shanghai/CN, 4 Naples/IT purpose: To compare contrast enhancement with iomeprol (400 mgI/mL) vs iodixanol (320 mgI/mL) in patients undergoing contrast-enhanced liver multidetector CT (MDCT). material and methods: 183 patients received equi-iodine doses (40 gI) of iomeprol-400 or iodixanol-320 IV at 4 mL/sec. Liver MDCT was performed using scanners with at least 4 detector rows. Two off-site, independent, blinded readers assessed images at the abdominal aorta, inferior vena cava (IVC), portal vein, and liver parenchyma. Descriptive statistics were used to summarize the contrast density (HU) measurements for the two study groups. The mean contrast densities achieved in each of the four regions of interest were compared and 95% confidence intervals estimated. results: 91 patients received iomeprol-400 while 92 received iodixanol-320. The two study groups were comparable with regard to sex, age, weight, and race. Iomeprol-400 resulted in significantly greater arterial phase enhancement of the abdominal aorta compared to iodixanol-320 ( In different experimental studies, hepatic damages were shown histopathologically in acute pancreatitis but there are a few studies about perfusion disorders that accompany these histopathologic changes. Perfusion CT (pCT) provides the ability to detect regional and global alterations in organ blood flow. The purpose of the study was to describe hepatic perfusion changes in experimental acute pancreatitis model with pCT. material and methods: Forty Sprague-Dawley rats of both genders with average weight of 250 grams were used. Rats were randomized into two groups. pCT was perfomed. Perfusion maps were formed by processing the obtained images with perfusion CT software. Blood flow (BF) and blood volume (BV) values were obtained from these maps. All pancreatic and liver tissues were taken off with laparotomy and histopathologic investigation was performed. Student T test was used for statistical analyses.

B 42 DOI: 10.1007/s10406-008-0008-8 results: Our study showed the development of histopathologically changes like hepatic portal inflammation, sinusoidal dilatation and hepatocytes degeneration. In pCT, we found statistically significant increase in blood volume in both lobes of liver and in blood flow in right lobe of the liver (p<0.01). Although blood flow in left lobe of the liver increased, it did not reach statistical significance.

The quantitative analysis of liver parenchyma with pCT showed that acute pancreatitis causes a significant perfusion changes in the hepatic tissue.

Vascular enhancement in Gd-eoB-dtpa and Gd-dtpa enhanced dynamic liver mrI in an animal model: Oxaliplatin therapy for the treatment of colorectal metastases may induce sinusoidal obstructive syndrome (SOS). SOS causes the liver to become friable and haemorrhagic and so pre-operative diagnosis is important. This study investigated the diagnosis of SOS using superparamagnetic iron oxide (SPIO)enhanced T2w GRE imaging. material and methods: 126 patients with treated colorectal metastases underwent unenhanced MRI followed by T2w GRE sequences after SPIO. The images were reviewed by two experienced observers in consensus who determined the presence and severity of linear and reticular hyperintensities, indicating SOS-type liver injury. In 60 patients with histological verification of the MR findings, sensitivity, specificity, PPV and NPV, for the detection of moderate to severe SOS, were calculated. results: 28/64 surgical and 21/62 non-surgical patients had moderate to severe SOS on post-SPIO MR; unenhanced images were unhelpful for diagnosis. 26/28 and 20/21 were treated with an oxaliplatin based chemotherapy regime. MR achieved a sensitivity of 87% (95% CI's: 66-97%), a specificity of 89% (95% CI's: 75-97%), PPV of 83% (95% CI's: 63-95%), and NPV of 92% (95% CI's: 77-98%). SOS was never found at surgery or histology in patients whose background liver parenchyma was normal on SPIO-enhanced MR. Conclusion: SOS is present in a significant proportion of patients with treated colorectal metastases and is effectively detected on SPIO-enhanced T2-w GRE images. 1±15 years) with diagnosed HHT or first degree relatives underwent screening MRI to ascertain cerebral, abdominal and pulmonary involvement. Of these patients, 38 presented with arteriovenous malformations (AVMs) of the liver and were further investigated before and after Gd-BOPTA administration at 0.05 mmol/kg bodyweight. Both dynamic and hepatobiliary phase imaging was performed. results: Patients with liver AVMs fell into two broad groups. In 19 patients, a prominent celiac trunk/hepatic artery and multiple regenerative hepatic lesions were present and the overall liver size was increased. The remaining 19 patients had hepatic AVMs, a prominent celiac trunk/hepatic artery and tortuous intrahepatic vessels but no regenerative nodules. In this group, the liver size was normal or decreased and 9 patients presented with RV-insufficiency. Conclusion: Two distinct pathophysiologic mechanisms seem to occur: 1) if regenerative nodules are present, these seem to result from arterio-portal shunts with local overgrowth of hepatic tissue reflecting increased arterial supply.

Lesions on MRI after Gd-BOPTA demonstrate similar enhancement to FNH suggesting a similar developmental mechanism; 2) in HHT patients without regenerative nodules, the blood-flow bypasses the liver through direct arteriovenous shunts. Thus, the liver size remains unchanged although an increased RV-volume load results in RV-insufficiency. cirrhotic patients (50-63 years old). All patients underwent imaging examinations, including contrast enhanced ultrasound (CEUS), multidetector computed tomography (MDCT) and magnetic resonance (MR), followed by core biopsy. results: All lesions were located in the right hepatic lobe and were homogeneously hypoechoic at baseline US. At CEUS, the lesions appeared hypoechoic, without bubbles perfusion. At dynamic triple-phase MDCT, all lesions appeared hypodense both in pre-contrast and after contrast injections, without any significant contrast uptake. RM showed hypointensity in T1-w images in all lesions; in T2-w images, 10 lesions were iso-hypointense and 2 were hyperintense at the periphery, with hypointense central area. After Gadolinium-BOPTA administration, lesions were hypointense both in dynamic and hepatobiliary acquisitions. All patients underwent percutaneous US-guided core biopsy. At histopathology, all lesions consisted of a fibrotic capsule with inflammatory chronic cells and a central core of amorphous necrotic material. All specimens, analyzed with Ziehl-Neelsen, Gram and periodic acid schiff, were negative for bacteria, fungi or parasitic infection. In the absence of definitive evidence, The Association of Surgeons of Great Britain recommends a single CT scan of the abdomen and thorax during the first two years. The aim of this study was to determine the benefit from more intensive imaging surveillance in identifying resectable liver metastases and the effect on survival outcome. material and methods: A prospective analysis of 125 patients, who underwent curative resection of CRC, was entered into an intensive imaging surveillance programme. Patients underwent a CT abdomen and thorax at 3-6 monthly intervals for two years and then annually for a further three years. results: Duke's stage was recorded at presentation (Duke's A 19%; B 43%; C1 34%; C2 4%). CT identified metastases in 18 patients (A 1; B 3; C1 12; C2 2). Twelve were diagnosed on the first CT, four on the second, two on the third and none on subsequent follow-up (liver: 16; liver and lung: 2). Five patients underwent hepatic resection and three are alive at two years. All resectable liver metastases were reported in the first year. Conclusion: Patients with advanced stage CRC are at greatest risk of liver metastases and most present in the first post-operative year. Early intensive imaging surveillance increases the detection of resectable liver metastases and improves survival.

Ct perfusion of rectal carcinoma monitoring response to neoadjuvant treatment: initial results P. Paolantonio 1 , R. Ferrari 2 , P. Lucchesi 2 , F. Vecchietti 2 , M. Rengo 2 , A. Laghi 2 ; 1 Rome/IT, 2 Latina/IT purpose: To prospectively monitor changes in rectal cancer perfusion after combined neoadjuvant chemotherapy and radiation therapy with perfusion computed tomography (CT). material and methods: Eleven patients with rectal adenocarcinoma (7 men, 4 women) underwent perfusion CT on a 64-MDCT scanner; all of them underwent neoadjuvant chemotherapy and radiation therapy. In all patients, perfusion CT was repeated neoadjuvant therapy. Dynamic perfusion CT was performed for 50 seconds after intravenous injection of contrast medium. Blood flow (BF), blood volume (BV), mean transit time, and permeability-surface area product (PS) were calculated in the tumor and in normal rectal wall. Wilcoxon signed-rank was used for data comparison. results: BF, BV, and PS were significantly higher in rectal cancer than in normal rectal wall (P<0.001). BF, BV, and PS significantly decreased after combined chemotherapy and radiation therapy (P<0.01). To determine diagnostic performance of MRI for predicting T-stage and N-stage with and without lymph node specific contrast in primary non-locally advanced rectal cancer in three regional centers and one expert center. material and methods: From February 2003 till October 2007, 327 rectal cancer patients were enrolled and received an USPIO MRI (Sinerem®). The local radiologists (non-experts) and an expert MR radiologist prospectively predicted the T-stage and the N-status first on T2WTSE images (USPIO-), then on the combined T2WTSE and 3DT2*(USPIO+), blinded for each other's results. The expert prospectively double read each MR of the regional patients. Reference standard was histology. results: 130/327 were non-locally advanced patients and used for analysis (42/130 were regional inclusions). 42 out of these 130 had pN+. T1 and T2W images were reviewed by two radiologists in consensus. Pelvic nodal size (<5 mm; 5.1-10 mm, 10.1-15 mm, 15.1-20 mm, >20 mm), signal intensity (hypo-, iso-or hyper-intensity), appearances and distribution (inguinal, external iliac (anterior, medial, lateral groups), internal iliac, common iliac, obturator, presacral) were recorded for each patient. Follow up imaging (MRI or CT) allowed assessment of outcome; mean patient follow up was 14 months. results: 521 nodes were identified in the following distributions: inguinal (388 (74%)), external iliac (51(10%)), internal iliac (14 (3%)), common iliac (15 (3%)), obturator (16 (3%)), and presacral (37 (7%)). 103/521 (20%) nodes were greater than 1 cm in size; the majority were inguinal (79/103 (77%)) or external iliac (16/103 (16%)), of homogenous high signal intensity on T2W. No nodal relapse following chemoradiation was identified where nodes were <1 cm. Conclusion: Nodal disease in squamous anal cancer most commonly involves inguinal, external iliac and obturator groups; these areas must be encompassed in radiotherapy.

Intra and inter observer agreement for remote 3d anal endosonography reporting P. Wylie, R. Ahmad, S. Ghosh, M. Marshall, D. Burling; Harrow/UK purpose: To assess inter and intra-observer variability for anal endosonography (AES) using remote 3D volume review. material and methods: 50 consecutive AES examinations from patients with symptoms of anal incontinence (excluding fistula-in-ano) referred to our centre were accrued by a study coordinator and reviewed independently on remote workstations using commercially available 3D review software by two experienced radiologists (observers A and B; >1000 cases each), blinded to clinical history (no time constraint). The dataset was read twice to assess intra-observer agreement (temporal separation 4 weeks to reduce recall bias). Classification of internal and external sphincter disruption/degeneration was recorded by each observer and, following statistical advice, the resulting data (inter/intra-observer) was compared using weighted Kappa statistic. results: Dataset comprised 13 normal/37 abnormal examinations from 42 females/8 males (Median 57 yrs). For internal sphincter classification, observers A and B agreed with their initial read on 49 (98%) Kappa 0.95 (very good: standard error 0.14); and 41 (82%) Kappa 0.63 (good; SE 0.14) occasions, respectively. Corresponding data for external sphincter were 47 (94%) Kappa 0.79 (good; SE 0.14); and 37 (74%) Kappa 0.37 (fair; SE 0.13) for observers A/B. Inter-observer agreement was very good to moderate for both reads for internal sphincter classification (Kappa 0.91/0.50; SE 0.14/0.13) but varied between good/fair for external sphincter classification (Kappa 0.65/0.31; SE 0.14/0.12). Conclusion: Intra and inter-observer agreement for remote AES reporting by highly experienced radiologists is variable but can be very good.

spectrum of mr-defecography findings in patients with anismus C.S. Reiner, A. Solopova, R. Tutuian, B. Marincek, D. Weishaupt; Zurich/CH purpose: To determine the frequency of MRI findings in patients with anismus and to compare these findings to a control group with constipation. material and methods: Forty eight patients (34 females, 14 males; mean age, 48 years) with clinically suspected anismus referred for anorectal manometry and MR-defecography were included. According to the final diagnosis, based on the Rome II criteria, patients were divided into two groups: patients with anismus (n=18) and constipated patients without anismus (control group, n=30). MRimages were retrospectively reviewed by two independent radiologists with regard to the time of evacuation, number of attempts to evacuate, changes in the anorectal angle on straining, paradoxical sphincter contraction, and the presence of additional pelvic floor abnormalities. Interobserver variability was analyzed by calculating kappa statistics. results: In patients with anismus, MR-defecography revealed evacuation inability in 9 patients (50%), increased time of evacuation compared to the patients with constipation (191 vs 113 sec, p<0.001), increased number of attempts to evacuate (mean 6.1 vs 3.5, p<0.05), higher frequency of abnormal anorectal angle changes on straining (9 (50%) vs 1 (3.3%)). Paradoxical sphincter contraction was observed solely in 15 (83.3%) patients with anismus. Interobserver agreement was good to excellent.

Using MR-defecography the detection of impaired evacuation (including the evacuation inability), increased number of attempts to evacuate and the presence of paradoxical sphincter contraction are highly suggestive for anismus.

11:00 -12:30 topkapi B

Bile ducts: diagnosis and intervention

Hepatobiliary kinetics of a liver-specific contrast agent (Gd-eoB-dtpa) in patients with diffuse liver disease at 1.5 t and 3 t A. Bethke 1 , K. Engellandt 1 , G. Gaffke 2 , M. Laniado 1 , C. Stroszczynski 1 ; 1 Dresden/DE, 2 Magdeburg/DE purpose: Primary or metastatic liver tumors often arise in patients with preexisting diffuse liver disease; therefore, it is imperative to evaluate contrast agent performance under these conditions. The aim of the study was to investigate the hepatobiliary kinetics of a liver-specific contrast agent in patients with diffuse liver disease. material and methods: Eighty patients were divided in 4 groups: 1. no diffuse liver disease/control group (n=28), 2. cirrhosis (n=16), 3. chemotherapy-induced steatosis (n=20), and 4. cholestasis (n=16). Standard MRI-protocol was used in various scanners at 1.5-3.0 T. Manually defined regions of interest were used to measure signal intensity of the liver and the bile duct before and after contrast material administration (20 seconds, 60 seconds, 10 minutes and 20 minutes). Percentage increase of enhancement was evaluated. results: Percentage increase of enhancement (control group 114%) was significantly reduced in patients with liver cirrhosis (84%) or cholestasis (55%) but not in steatosis. Biliary excretion was significantly reduced in patients with cholestasis (145%) compared to groups 1-3 (1793%, 1409%, 1393%). Conclusion: Hepatic enhancement with Gd-EOB-DTPA can be impaired by the presence of cholestasis and liver cirrhosis. However, enhancement was sufficient for diagnostic purposes. While T1-w imaging of the bile duct in patients with cholestasis is hampered by reduced enhancement, biliary excretion may be characterized.

safety and efficacy of Ct cholangiography K.P. Lim 1 , N. Grunshaw 2 ; 1 Yarm/UK, 2 Darlington/UK purpose: CT cholangiography (CTC) is an alternative technique for biliary investigation in patients unable to undergo MRCP. Concerns regarding adverse reactions and image quality in the presence of impaired hepatic function have resulted in its relative underutilisation. The purpose of this study is to assess the diagnostic efficacy and safety profile of CTC with iotroxate infusion and to assess its success rate in the presence of abnormal liver function tests (LFTs (n=5) guidance. An 18G biopsy needle was used for biopsy sample. Sample notch size was selected from 9 to 24 mm. One to 15 samples (median, 5 samples) were obtained per nodule and fixed. In 16 cases with elevated risk of haemorrhage, biopsy tract was embolised. Post-procedural imaging was performed to search for immediate complication. The medical charts, pathology reports and radiology files were retrospectively reviewed. results: Multisampling NCB was successfully completed in 102 of 104 procedures (98%), while two biopsies were discontinued due to vasovagal syncope. Tissue specimens were satisfactory for histologic diagnosis in 97 of 102 biopsies (95%). In five cases, samples were considered inadequate for specific diagnosis. There were 23 primary and 57 secondary malignant tumours, 17 benign tumours and 6 inflammatory lesions. According to SIR classification, no procedure-related complication was observed. Four minimal asymptomatic perihepatic collections were observed but not treated. (21) with a mean weight loss of 12 kg (range, 2-30 kg), and gastroparesis (3). All patients had visceral occlusive disease with significant stenoses in one (11), two (20) or three (2) mesenteric vessels. Follow-up parameters included maintained patency on Doppler sonography and sustained clinical benefit. results: Balloon angioplasty alone was performed in only one of the arteries in 29 patients (superior mesenteric artery or SMA, 20; celiac artery or CA, 9) and in two arteries in 3 patients (SMA and CA). Stenting was required in 17 patients (SMA, 14; CA, 3). All procedures but one were technically successful (97%). Three major puncture-site complications required surgery (2 hematomas, 1 pseudoaneurysm). Immediate clinical success was achieved in 27 patients (93%). At a mean follow-up of 35 months (range, 3-108 months), 20 patients were symptom free, 7 had recurrent pain with angiographic restenosis successfully revascularized percutaneously (4) , 15 patients underwent elective endovascular procedures for 10 splenic, 2 hepatic, and 3 renal artery aneurysms. Eight balloon expandable and 2 self-expandable stent-grafts were used in ten patients affected by 3-6 cm aneurysms. AVP was used to occlude the necks whereas cut up Teflon guidewire sheaths were employed to fill up the aneurysm sac in three patients with 9-13 cm Giant Splenic Aneurysms (GSA). CTangiography was performed before patient discharge, at 6 and 12 months thereafter. results: Successful angiographic exclusion was obtained in all cases. Segmental splenic infarction occurred in all patients treated with embolization and in one treated with stent-graft. Post procedure CT showed complete aneurysms thrombosis and patency of the stent-grafts in all cases. At mean FU of 24 months, occlusion of the graft occurred in one case.

The endovascular treatment of VAAs with stent-graft and AVP represents a valid therapeutic option. The former are fully respective of the vascular anatomy while the latter reduce the risk distal migration during embolization of GSA with short and large proximal necks. Late FU confirms the durability of the aneurysm exclusion and the low clinical relevance of late stent graft occlusion.

Initial experience with reconstruction of aortic pathologies based on 3d prototyping models generated Background: Cholangiocarcinoma (CAC) is the most common primary malignancy of the biliary tree and is classified as either intra or extra hepatic, and their typical growth pattern can be classified as mass-forming, periductal-infiltrating, or intraductal-growing type. CAC is further classified according to its anatomic location and longitudinal extension along the bile ducts into four types which has therapeutic and prognostic implications. Imaging findings or procedure details: CAC demonstrates a wide spectrum of radiological appearances and is characterised using US, CT and MRI. MRI and MRCP due to their intrinsic high tissue contrast and multiplanar capability are more effective in detecting, preoperatively assessing, and predicting involvement of bile ducts, vessels and hepatic parenchyma. CAC appear hypointense on T1W and hyperintense on T2W images. On dynamic imaging, CACs show moderate peripheral enhancement followed by progressive and concentric contrast enhancement. Using gadolinium contrast with biliary excretory properties can accurately locate the exact site of biliary obstruction.

Conclusion: Good quality gadolinium-enhanced MR is the optimal, non-invasive imaging examination for staging and determining resectability of suspected CAC.

atypical mrCp appearances of the operated biliary system: a pictorial review X. Merino-Casabiel, R. Dominguez-Oronoz, S. Gispert-Herrero, V. Pineda-Sanchez, I. Miranda; Barcelona/ES Learning objectives: To describe the common and non-common features and principal complications of the operated biliary system by means of MRCP. Background: MRCP is a fast, non-invasive, effective technique for imaging the biliary-pancreatic duct. The increasing use of laparoscopic biliary surgery, creation of biliary-enteral anastomoses, and progressive increase in liver transplantations requires a technique that allows early accurate diagnosis of postoperative complications and provides information for their management. Imaging findings or procedure details: We reviewed MRCP examinations performed in our center since August 1996, selecting postoperative studies of the biliary duct. Several types of atypical MRCP appearances of the operated biliary system are shown: (1) complications related to biliary anatomic malformations (e.g., low insertion of the cystic duct, abberant right hepatic duct, etc.); (2) 

Gallbladder carcinoma: pre-and post-treatment imaging evaluation A. Furlan 1 , J.V. Ferris 2 , K. Hosseinzadeh 2 , A.A. Borhani 2 , T.C. Gamblin 3 , D.A. Geller 2 ; 1 Udine/IT, 2 Pittsburgh, PA/US Learning objectives: To describe the appearance of gallbladder carcinoma (GBC) at US, CT, PET-CT, MRI, MRCP, and ERCP and to review the ability of each modality to diagnose and stage tumor extent. To discuss triage to available treatments according to tumor stage. To illustrate sequelae of different therapies. Background: GBC is the most common biliary tract malignancy, yet often eludes early diagnosis because symptoms tend to manifest at later stages when prognosis is grim. Surgery may be curative for early stages or palliative for later stages with a modest improvement in 5-year survival curves. As only one-third of patients are surgical candidates, chemo-and radiotherapy have been used with varying results. Imaging findings or procedure details: US, CT and MR are the imaging modalities most used in cases of suspected GBC. Usual appearances include diffuse asymmetric or focal gallbladder wall thickening, intraluminal polypoid mass, or a mass replacing the gallbladder lumen, with variable enhancement patterns after intravenous contrast administration. CT, MR and increasingly PET-CT are used to assess direct extension to the liver and adjacent organs, as well as spread to lymph nodes and distant sites. Background: PI techniques use the spatial sensitivity information inherent in an array of multiple receiver surface coils to partially replace time-consuming spatial encoding usually performed by switching magnetic field gradients. The reduction of the number of phase-encoding steps allows decreasing the acquisition time and, in single-shot sequences, the length of the echo train (ETL) and thus the duration of the readout period. Imaging findings or procedure details: Standard MRCP sequences described will include the following T2-weighted sequences: 1) projection technique, 2D thick slab half-Fourier-acquired single-shot turbo-spin echo (HASTE); 2) 2D multi-slice HASTE; and 3) 3D turbo-spin-echo (TSE). The distinct effects of PI on standard MRCP sequences will be described in detail: When applied to HASTE sequences, PI technique shortens the ETL and thus reduces the blurring of the image. When applied to 3D TSE sequence, PI reduces the acquisition time and allows obtaining of high resolution imaging with isotropic voxel size. Conclusion: PI increases quality and performance of MRCP sequences. Ultimately, these improvements in image quality may manifest better diagnostic accuracy. Imaging findings or procedure details: Imaging is frequently utilised in these patients to exclude more sinister pathology including bowel carcinoma, inflammatory bowel disease and ovarian lesions. This educational exhibit will review the literature using evidence-based techniques and draw on local experience to discuss the appropriateness of imaging modalities employed in IBS including plain radiography, ultrasonography, computed tomography, barium studies and MRI. The diagnostic yields, limitations and disadvantages (such as radiation dose) of these imaging modalities will be discussed. The perspectives of gastroenterologists will also be included in these discussions. Conclusion: Imaging is frequently employed in the evaluation of patients with IBS. Appropriate imaging algorithm will be proposed based on the review of local experience and a thorough review of the literature. 

Key learning objective: to illustrate the radiological presentation of Crohn's disease in the elderly S. Ghosh, N. Power; London/UK Learning objectives: To illustrate the radiological appearance of Crohn's disease in the elderly. Background: Crohn's disease typically presents at 2 peaks, commonly in the younger age group and less so in the older age group. However, with the use of cross sectional imaging, Crohn's disease has become increasingly recognized in the older age group where the radiological presentation may be difficult to distinguish from other common disorders. Imaging appearances can easily be confused with diverticulitis, ischaemia and carcinoma. Imaging findings or procedure details: This poster illustrates the difficulty and dilemmas of diagnosing Crohn's disease on imaging.

Conclusion: This pictorial review will illustrate the radiological manifestations of Crohn's disease as a mimic of other potential differential diagnosis. Background: Colorectal cancer is the second most common malignancy in Western societies. Recurrence has been reported to occur in up to 50% of patients following surgery with curative intent. Early detection of recurrence through intensive follow-up has been shown to significantly improve long-term survival. Imaging has an important role in follow-up, with CT imaging often being performed for the detection of recurrences and MR imaging performed in selected cases for problem solving or restaging. Imaging findings or procedure details: We have reviewed images of colorectal cancer patients followed up at our centre between January 2004 and January 2008. Relevant colorectal anatomy including vascular supply and lymphatic drainage will be reviewed. We will present CT and MR images of local and distant recurrences. Some examples include recurrences involving the vaginal vault, seminal vesicles, pelvic wall and retroperitoneum. We will also describe and illustrate subtle, early recurrences and progression over time.

Conclusion: Early detection of recurrence following curative colorectal cancer surgery is important as it can enable more effective treatment and improve patient survival. An appreciation of patterns of spread and appearances of early recurrence is important for the radiologist.

Ct examination for diagnosing appendicitis: clinical, pathological and Ct correlations Y. Kobashi 1 , H. Okamoto 2 , R. Kodama 2 , Y. Nakajima 2 , K. Shimoyama 1 ; 1 Fujisawa/JP, 2 Kawasaki/JP purpose: To categorize acute appendicitis using CT examination and correlate with clinical and pathological findings. material and methods: We investigated 32 patients (male 17, female 15, mean age 31.1 years and ranging from age 13 to 80) who were diagnosed with acute appendicitis on both of CT and operation. The acute appendicitis was classified into following three CT findings considering pathological findings before operation; 1) Appendiceal wall thickening and enhancement without periappendiceal enhancement which were suspected with catarrhal appendicitis by pathology, 2) Appendiceal wall thickening and enhancement with periappendiceal enhancement which were suspected with phlegmonous appendicitis by pathology and 3) Periappendiceal enhancement with/without abscess formation, cecal edema without appendiceal enhancement which were suspected with gangrenous appendicitis by pathology. We correlated these findings with operative findings and pathological diagnosis. results: Ten patients were categorized with catarrhal appendicitis, fourteen patients with phlegmonous appendicitis and three patients with gangrenous appendicitis. We misdiagnosed four patients of appendicitis. Three patients had no obvious findings for acute appendicitis on CT but were operated and diagnosed catarrhal appendicitis. One patient was diagnosed with enterocolitis on CT but operated. He was diagnosed with gangrenous appendicitis with perforation by pathology. Background: The sigmoid colon and its mesentery are commonly involved by inflammation and neoplastic processes. Differentiating between these two entities is a frequent challenge to the radiologist and often requires endoscopic correlation. The location of the sigmoid colon adjacent to the pelvic organs creates a recognizable pattern of local spread of disease and fistula formation. The attachment of the sigmoid mesocolon predisposes to volvulus and creates a potential space for internal hernias. Imaging findings or procedure details: A range of disease involving the sigmoid colon and mesentery will be illustrated using US, CT and MRI with pathological correlation. The examples include diverticular disease, infective colitis, neoplastic strictures, endometriosis, fistulas and sigmoid mesenteric cyst.

The awareness of the cross sectional imaging appearances of the different disease processes affecting the sigmoid colon and diagnostic limitations is important to reach the correct diagnosis.

Contrast 

Ct patterns of bowel wall thickening as a diagnostic tool in patients with acute abdomen E.M. Dieguez Costa, S.M. Novo, M. Barxias, B. Gonzalez, P. Borrego; Madrid/ES purpose: CT has been proven a useful method to evaluate those patients with acute abdomen because of its ability to display both mural and extraluminal abnormalities. The purpose of this study was to assess the capability of CT to categorize the major differential diagnosis in those cases of acute abdomen that course with bowel wall thickening (BWT). material and methods: The CT scans of 320 patients who were admitted to the emergency room in our institution over a period of two years were retrospectively reviewed. results: We found 220 cases with BWT. Among them, the following diagnoses were obtained: Neoplastic disease 40, ischemic colitis 11, infectious colitis 14, bowel inflammatory disease 30, diverticulitis 80, apendicitis 39, intramural hemorrhage 2, hypoalbuminemia related conditions and miscellaneous 4. Conclusion: BWT is a valuable CT sign in patients with acute abdominal pain. By analyzing symmetry and degree of wall thickness, wall attenuation, distribution and length of extent, contrast enhancing pattern, and perienteric change it was possible to substantially narrow the broad spectrum of differential diagnosis. Background: Laparoscopic surgery in colorectal cancer has been generally accepted because the technique is less invasive than open surgery. However, in this procedure, it is difficult to obtain images of the entire operative field under laparoscopy. Therefore, it takes a long time to identify the proper vessels where there might be major variations in each patient. Moreover, vessels and organs could be injured during lymph nodes dissection and vessel ligation under laparoscopic guidance. Therefore, it is quite important to perform a preoperative assessment of the vascular anatomy using a 3D-CTA before surgery. Imaging findings or procedure details: We performed multiphase contrast-enhanced examinations using a 64-channel MDCT. A total of 100 ml of nonionic contrast material was injected intravenously at a rate of 4 ml/s. Timing for arterial phase scanning was determined using bolus tracking technique. Portal phase imaging was performed 70 s after the start of bolus injection. 3D-CTA was reconstructed from CT images of 0.625-mm thickness on computer workstations by using volume rendering and maximum intensity projection techniques. Conclusion: A 3D-CTA is useful for the preoperative visualization of laparoscopic colorectal surgery.

Interposition of the left colon S. Uysal Ramadan, D. Gokharman, M. Kacar, I. Tuncbilek, P. Kosar, U. Kosar; Ankara/TR Learning objectives: To investigate the prevalence of ILC by CT and to discuss the significance of ILC. Background: The interposition of left colon (ILC) has been documented recently and reported more rarely than right colon variations. ILC was classified as retrogastric and retrosplenic types. Imaging findings or procedure details: The abdomen or chest CT examinations were performed by 64 slices CT scanner in 200 patients who suffered from different clinical symptoms. Among them, the ILC was identified in 3 (1.5%) patients. The upper part of the descending colon was located between the spleen and the left kidney, and extended up to the hemidiaphragm (retrogastric type) in two patients. In the third patient, the splenic flexure was seen in front of the left kidney, between the hemidiaphragm and spleen. The last ILC was a variant of the retrosplenic interposition because his spleen was located more caudally than normal position. For this reason, to the best of our knowledge, this type of ILC has been described for the first time in our study. Conclusion: ILC is a benign anatomical variation and can be easily diagnosed on CT images. Radiological recognition of ILC is important to prevent misdiagnosis of the colon such as abscess and to avoid unnecessary colon perforation during percutaneous nephrostomy or biopsy. Colonic diverticulosis is the most frequent cause of severe rectal bleeding. Complications of colonic diverticulitis include hemorrhage, perforation, fistulization, panperitonitis, abscess formation, and others. The latter occurs in more than 8% of patients with acute deiverticulitis. Imaging findings or procedure details: We reviewed abdominal CT of patients of acute abdomen with colonic diverticulosis. Colonic perforation with intraperitoneal free air, fistulization and spread of inflammation well depicted axial and optimal multiplanner reformatted images using MDCT with 0.6-1 mm of collimation. A rare perforation of sigmoid colon was caused by the impact of ingested foreign body in diverticulum. The hemorrhage from diverticula was diagnosed by pre-and post contrast-enhanced CT, and interventional treatment was done. Serious complications of colonic diverticulitis were thrombosis and gas formation of portal venous system, and perforation with venous intravasation of barium. One case was seen with splenic infarction due to thorombosis of portal and splenic vein secondary cholecystitis because of ascending colonic diverticulitis. , an emergent condition, is usually idiopathic in infants five to nine months of age. However neonates, older children and adults commonly have lead points. The purpose of this report is to describe CT findings of two cases with IS due to unusual pathologic lead points. material and methods: Abdominal CT scan of two patients was performed with a preliminary diagnosis of chronic intestinal obstruction. results: Case 1: A four-year-old boy had asymmetrical prominent wall thickening in the terminal ileum and right-sided colonic segments, and a metallic foreign body in cecum. Besides, there was an intracolonic soft tissue mass representing ileocolic IS in the right hemicolon. Laparotomy revealed ileocolic IS due to ileocecal mass along with a coin. Burkitt lymphoma was determined at histological examination. Case 2: A twelve-year-old girl had small bowel dilatation on CT.

There was wall thickening at the ileocecal region, and a small soft tissue mass that was suspicious of IS was observed in cecum. At endoscopic evaluation of the colon, cecal ulcerated mass and ileocolic IS were determined. Histological examination of the biopsy material revealed mucinous adenocarcinoma of cecum. Conclusion: CT can help predict pathological lead points of IS in older children with atypical presentation of intestinal obstruction. Although it is extremely rare in childhood, colon carcinoma and lymphoma along with a foreign body can act as lead points.

prediction of locally advanced colon cancer using high resolution t2-weighted mrI E. Rollvén, L. Blomqvist, T. Holm, J. Lindholm; Stockholm/SE purpose: To investigate the potential of high-resolution magnetic resonance imaging (MRI) for local tumour staging of colon cancer. material and methods: Twenty-four patients with colonic tumours were included and examined on a 1.5 T unit using a five-element phased-array coil. T2-weighted turbo spin-echo sequences (voxel size 3 x 0.5 x 0.5 mm) in the coronal and transverse as well as perpendicular to the long axis of the intestine at the tumour level were performed. The tumours were assessed with respect to localisation, relation to the peritoneum, retroperitoneal structures and adjacent organs. Surgical specimen were examined by a GI pathologist being the reference standard together with surgical findings. results: Five patients were excluded due to not satisfactory MRI quality (n=3), not verified cancer diagnosis after surgery (n=1), no surgery (n=1). Of the remaining 19 patients, according to histopathology, one patient had a T1-tumour, six T2, seven T3 and five T4 tumours, respectively. T-stage agreement between histopathology and MRI was achieved in 15 of 19 patients with MRI overstaging in three and understaging in one. In 80%, locally advanced disease was predicted by MRI. Conclusion: Selection of patients with locally advanced colon cancer for neoadjuvant treatment is needed, but there is yet no established imaging technique. In our study, 80% was correctly classified with preoperative high-resolution MRI. These data are promising for MRI to be the technique of choice.

Withdrawn material and methods: Patients with potentially resectable LM from colorectal cancer were evaluated using liver CT in combination with chest CT. Postoperatively, all patients were monitored for the development of pulmonary metastases. Chest CT was performed with a slice thickness of 3 mm. Patients with highly suspicious pulmonary lesions on the chest CT and limited to ≤3 in number underwent a metastasectomy. results: Forty-eight colorectal cancer patients with LM were evaluated. All patients underwent a liver resection and/or radiofrequency ablation. Of these, preoperative chest CT showed no lesions in 16 patients, while chest CT was positive in 32 patients (67%): 25 patients with lesions 1-5 mm and 7 patients with lesions 6-10 mm. Twelve patients (25%) developed pulmonary metastases during follow-up: one patient in the initial group without lesions (6%), 5 patients in the group with 1-5 mm lesions (20%) and 6 patients in the group of 6-10 mm lesions (86%). Three patients underwent a metastasectomy of pulmonary metastases. Conclusion: Chest CT appears valuable in determining the extent of pulmonary lesions and importantly in discriminating lesions > 5 mm suspicious for pulmonary metastases. Conclusion: Evaluation of the ratio between length and thickness of the involved colon segment can be used as a precise indicator to differentiate between neoplastic and inflammatory processes.

CtC in the diagnosis of large colonic lipomas I.G. Crespo, D. Cano, I. Vivas, M. Arraiza; Pamplona/ES Learning objectives: CTC has a role in the evaluation of the colon, especially when due to the lesion a complete colonoscopic examination may not be possible. Using 3D endoluminal images with different endoluminal rendering presets and 2D images, we can navigate through the entire colon to look for the lesion and we can not only see the fatty texture of the lesion but also localize the lesion more precisely. Surgical resection seems to be the ideal treatment. If the preoperative diagnosis and location can be made correctly, extent of surgery may be appropriately limited.

Background: Colonic lipomas are the third most common benign colonic tumor, after hyperplastic polyps and adenomatous polyps. They are relatively rare with and incidence reported between 0.03 and 4.4% . Most of them are small and asymptomatic and are found incidentally. About 20-25% of patients with a large lipoma more than 2 cm have related symptoms. The differential diagnosis is sometimes difficult, often misinterpreted with malignant tumors. Imaging findings or procedure details: We describe two cases of symptomatic giant lipoma of the colon, diagnosed by virtual colonoscopy following incomplete colonoscopy. Conclusion: Virtual colonocopy is an excellent method not only to diagnose the colonic lipomas and to examine the rest of the colon in case of incomplete colonoscopy but also to provide surgeons a more precisely anatomic location of the lesion.

CtC in acromegaly L. Bacigalupo 

Withdrawn by authors

Bowel preparation for multidetector row CtC: comparison of three different cleansing preparations M. Slattery, E. Thornton, M. Morrin; Dublin/IE purpose: Sodium phosphate has been the main colonic cleansing agent utilised prior to CT colonography (CTC). However, concerns regarding safety have led to restriction in its use. This study prospectively compares three bowel cleansing preparations. material and methods: Group 1 (n=20) received single dose Sodium phosphate; Group 2 (n=20) received sodium picosulphate (Picolax) and senna; and Group 3 (n=20) received a combination of Picolax and 1L 2% oral diatrizoate meglumine (gastrograffin). Overall preparation quality and diagnostic confidence between groups was analysed using the Kruskall-Wallis test and Dunn's post hoc analysis. Colonic distension scored similarly in all 3 groups (p>0.05). There was significantly less retained fluid (p<0.05) and significantly more residual faeces (p<0.05) in subjects prepared using sodium phosphate. No significant difference in terms of residual fluid or faeces was observed between Groups 2 and 3 (p>0.05) and overall study quality was superior in subjects prepared with Picolax and senna (Groups 2 and 3) (p<0.05). Overall confidence in diagnosis was significantly higher where oral labelling with gastrograffin was performed (Group 3) (p<0.05). results: Picolax preparations are superior to sodium phospate preparation prior to CTC. The increased overall confidence in diagnosis observed in subjects who received a combination of Picolax and oral gastrograffin is attributable to the quality of labelling of residual fluid and faeces. Conclusion: Picolax preparations are superior to sodium phospate preparation prior to CTC.

CtC: which are the right scanner parameters to use? P. Paolantonio 1 , R. Ferrari 2 , P. Lucchesi 2 , F. Vecchietti 2 , C.N. de Cecco 1 , A. Laghi 2 ; 1 Rome/IT, 2 Latina/IT Learning objectives: To describe acquisition parameters of CTC protocols using different scanners generations moving to 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 among scan width, image noise, patient dose, image artefacts, breathhold times, and the number of reconstructed images to be viewed and archived. Imaging findings or procedure details: We will discuss the relationship among collimation, tube current settings, patient dose exposure and accuracy in polyp detection of various CTC protocols valid for different scanner generation. We will offer some practical guidelines for CTC technique based on evidences of literature and 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 to do 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 64-slice MDCT, sub-millimeter collimation will be mandatory, although clinical benefits are still unclear. 

optimization of oral labelling in CtC: two hours versus twenty-four hours of oral labelling prior to CtC E. Thornton, M. Slattery, J. Bracken, M. Morrin; Dublin/IE purpose: Despite bowel cleansing for CT colonography (CTC), residual fluid/stool may be problematic. Oral labelling of fluid/stool helps distinguish true polyps from fluid/stool. We compared CTCs of those who consumed oral diatrizoate meglumine (Gastrograffin) for 2 hours before CTC with those who consumed Gastrograffin for 24 hours before CTC. material and methods: This was a prospective study of 40 patients, who received full bowel preparation with sodium picosulphate and oral labelling with 1000 cc 2% Gastrograffin. Group 1 (n=20) consumed 1000 cc Gastrograffin over 2 hours before CTC. Group 2 (n=20) consumed 1000 cc Gastrograffin over 24 hours before CTC. Using axial images, the colon was evaluated by segment and analysed regarding colonic distension, residual fluid/stool, and quality of labelling of fluid/stool using 5-point scales. Overall examination quality and overall diagnostic confidence for each group was also analysed. Statistical analysis included Mann Whitney U test. p<0.05 was taken as statistically significant. results: 100% cases had good/excellent colonic distension. Residual fluid/stool was similar in both groups (p<0.05). Labelling of fluid and stool was significantly better in Group 2 (p<0.01 and p<0.05, respectively). Overall quality and overall confidence in diagnosis was significantly better in Group 2 (p<0.05 and p<0.01, respectively).

This study demonstrated that oral labelling over 24 hours before CTC results is significantly better in overall quality and overall confidence in diagnosis, when compared with oral labelling over 2 hours before CTC. weeks. An experienced radiologist reported the CTC data, also recording confidence a large polyp or cancer could be excluded from each of 6 colonic segments (from 1 to 4 (high)). Combined PET-CTC data was then reviewed in consensus with a nuclear-medicine physician and the incremental benefit of PET on sensitivity/specificity (in comparison to a full colonoscopic reference) and diagnostic confidence (Fisher exact test) calculated on statistical advice. results: 6/22 patients harboured 7 polyps. CTC sensitivity for polpys 1-5 mm, and >10 mm was 1/5 (20%, 95% CI 0 to 55) and 2/2 (100%), respectively with no incremental benefit with PET. Polyps>1 cm were PET avid. However, three PET non-avid CTC false positives (9, 12, 6 mm) were correctly dismissed after combined review improving specificity from 0.82 (95% CI 0.62 to 1.0) to 1.0.

Diagnostic confidence was ≤2 in 9/132 colonic segments on CTC, improving to a score of 4 in all 9 after combined PET-CTC review (p=0.002). Conclusion: Simultaneous PET acquisition with non-laxative CTC helps improve specificity and diagnostic confidence, but not sensitivity. Recruitment continues and full data will be presented. The objective of the current study was to determine the value of Magnetic Resonance Colonography (MRC) for the assessment of colonic Crohn's Disease (CD). material and methods: 36 patients with CD underwent colonoscopy and MRC using a 3.0 T unit. T2-weighted and pre-and post-contrast-enhanced T1weighted sequences were acquired. Endoscopic lesions were graded as inactive, mild/moderate and severe. The MRC parameters evaluated in each colonic segment were: wall thickness, pre-and post-contrast wall signal intensity, relative contrast enhancement, edema, ulcers, pseudopolyps, and adenopathies. results: A total of 121 colonic segments were available for evaluation (inactive n: 71, mild/moderate n: 29, severe n: 21). Significant differences were found between inactive and mild/moderate disease, and between the latter and severe disease for wall thickness, post-contrast wall enhancement, relative enhancement, edema and ulcers. Linear logistic regression analysis demonstrated that the variables with independent predictive value for determining disease activity and severity were wall thickness, signal intensity after contrast, % enhancement and presence of ulcers. Applying the corresponding coefficients, the sensitivity and specificity for detecting disease activity were 0.83 and 0.84, and for detection of severe lesions 0.96 and 0.93, respectively.

The high sensitivity and specificity of MRC for detection of disease activity and for assessment of lesion severity bring about the possibility of using MRC as an alternative to endoscopy for the evaluation of colonic CD.

Imaging in pregnancy. To illustrate typical imaging findings of range of conditions which result in AP in pregnancy on various modalities and potential pitfalls that can lead to mis-diagnosis. To discuss limitations and specific safety issues in imaging of abdomen in pregnancy. Background: Imaging of abdomen for suspected GI and hepatic disease during pregnancy is assuming greater importance. Like clinical evaluation, imaging of the abdomen and pelvis is challenging but is vitally important to prevent delayed diagnosis or unnecessary interventions. Choice of imaging modality is impacted by factors which impact fetal safety such as ionizing radiation and MRI. Imaging findings or procedure details: The most common indication, excluding fetal assessment, for abdominal imaging during pregnancy, is abdominal pain. There is a broad differential diagnosis for abdominal pain (AP) including conditions which are not related to pregnancy and pregnancy-related conditions. This educational exhibit will discuss issues in abdominal imaging in pregnancy, including safety issues and difficulties in interpretation in three trimesters. Conclusion: Imaging of the acute abdomen for AP in pregnancy is increasingly requested by clinicians. Appropriate utilisation and interpretation of imaging is vital to allow accurate diagnosis, expeditious management and avoid potential risks to mother and fetus. 

does the second mrI scan post neo-adjuvant longcourse treatment for rectal cancer alter management? A.J. Sambrook, A. Lowe, A. Thrower, C. Kay; Bradford/UK purpose: In our institution, in accordance with Regional Cancer Network Guidelines, patients who receive neo-adjuvant long-course chemoradiotherapy for rectal cancer undergo a post-treatment scan to determine tumour response before surgery. This study examines whether this scan alters patient management. material and methods: A retrospective audit was performed of 65 patients who had undergone long-course chemoradiotherapy (2004) (2005) (2006) (2007) . The surgery planned following the initial multidisciplinary meeting was recorded. A copy of the operative notes was then reviewed, and the actual surgery performed recorded. results: 65 patients underwent chemoradiotherapy. Five did not proceed to surgery (patient choice/unsuitability for anaesthesia). Of the remaining 60 patients, 56 underwent a standard abdomino-pelvic resection. The other four patients had pelvic clearance surgery, which was predicted as necessary on the initial scan. The post treatment MRI did not change the surgical approach in any of the 60 cases.

The post treatment scan did not affect the surgery in any of the patients. At a cost of €775 per scan (in our institution), the potential cost saving of not performing the second scan in these patients is €15,500 per annum. Furthermore, the results of this study indicate, at the very least, the need for a more extensive review of the requirement for this costly and potentially unnecessary examination. (5), muscular (1), others (5)). MRC was able to define the presence and localization of all fistulas (100% sensitivity). 19 patients showed no fistula that was verified by surgery (5) 

Improving 

Crohn's disease and dark-lumen-mr: whole intestinal distension with oral administration of polietilenglicole in "2 steps" I. Sansoni, R. del Vescovo, G. Della Longa, E. Piccione, B. Beomonte Zobel; Rome/IT purpose: Crohn's Disease (CD) contemporary affects small and large bowels. We propose an alternative method to distend and evaluate the whole unprepared bowel: dark-lumen-MR technique with oral administration of polietilenglicole (PEG) in 2 stages. material and methods: 45 patients with suspected CD have been examined, with no previous intestinal cleansing. They were asked to drink twice 1.5 liters of a polietilenglicole solution: 2-4 hours and 45 minutes before MR examination. A darklumen-MR protocol has been acquired on a 1.5 Tesla magnet: T2-weighted and True-FISP sequences on axial and coronal planes and T1-weighted sequences, in basal condition and after paramagnetic contrast e.v. administration on axial plane. Grading of bowel distension, cleansing and parietal inflammation (active, inactive, negative) was defined for each segment using conventional colonoscopy, postbiopsy histopathology results and serological tests findings as gold standard. results: Only 9% of bowel segments were not correctly distended (mainly the jejunum), and 7% of colonic segments where hindered by feces (especially distal colon). In 26 pathologic segments, a complete correlation of presence and location of flogosis has been evidenced, but in 6 segments (all in the same patient) the grading of flogosis was not correct. Conclusion: Whole bowel assessment with "2 steps" distension is feasible, satisfying, does not need for particular colonic preparation and does not present the discomfort of direct retrograde colonic water distension, especially when perianal complications are present. The aim of our study is to assess the capability of dark-lumen MR-Colonography (MRC) in detecting the number, localization and complication of colorectal diverticula (CD) obviating colonic cleansing and manual colon retrograde distension. material and methods: A total of 29 symptomatic patients, referred for conventional colonography and/or CTC underwent MRC without any previous bowel cleansing and manual distension. MRC protocol was acquired on a 1.5 T scanner with high-performing gradients on axial and coronal planes using T2weighted (TSE and HASTE), unspoiled (true-FISP) and spoiled (FLASH) GRE T1weighted sequences. Spoiled GRE was acquired before and 75 seconds after intravenous administration of paramagnetic contrast agent. MR examinations were analysed on per-patient basis and on a per-segment basis (ascending, transverse and descending colon and rectum) that were stratified per number of diverticula (0, 1, 2, 3, 4, 5-10, >10). results: The "per-patient" analysis demonstrated a good diagnostic accuracy subordinated to patient compliance (93%), whereas the "per-segment" defines a higher representation of diverticula in sigmoid tract (65% of patients) than in cecum and rectum (0% of patients). Conclusion: Dark-lumen MRC is a promising modality with high accuracy for detecting CD. This technique, moreover, overcomes the risk of diverticulum perforation, inherent in retrograde bowel distension and that of ionising radiation. Belfast/UK, 2 Craigavon/UK purpose: With the advent of 'conservative' therapies including photodynamic therapy and endoscopic mucosal resection for Barrett's oesophagitis and high grade dysplasia, accurate staging has become increasingly important. We report our experience in these patients with EUS. material and methods: Retrospective review of 25 consecutive patients referred for EUS for assessment of Barrett's with high grade dysplasia and/or stricture or polyp. The findings were compared with subsequent oesophagectomy histology or endoscopy and biopsy follow up. results: 9 patients were found to have invasive tumour on EUS and this was confirmed in all 9 either by oesophagectomy, OGD and oncology follow up, or by endoscopic mucosal resection. 8 patients underwent oesophagectomy, 6 for invasive tumour and 2 for dysplasia only, with pathological agreement with EUS findings in 7/8. The one discrepancy was a EUS case of thickening only with no invasion, but pathology showed a T1 lesion. 13 patients with no evidence of invasion were followed up with OGD and biopsy, with or without photodynamic therapy, for an average of 15.8 months, with no cases of 'missed' invasion occurring. Therefore, in our experience, the sensitivity, specificity and positive predictive value of EUS in complex Barrett's was 90, 100 and 100%, respectively. Conclusion: EUS is valuable in the assessment of Barrett's oesophagitis and high grade dysplasia where conservative therapy is increasingly being used.

the utility of mdCt perfusion examination in detection of metastatic lymph nodes of esophageal cancer G. Tóth, L. Tóth, E.C. Turupoli, V. Bérczi; Budapest/HU purpose: Assessment of the role of computed tomography perfusion (CTP) study for differentiation between malignant and benign mediastinal and retroiperitoneal lymph nodes in oesophageal cancer. material and methods: A prospective study was conducted on 14 consecutive patients (9 M, 5 F aged 37-62) with histologically proven esophageal cancer. Perfusion study was done after contrast-enhanced conventional chest and abdominal MDCT study. Perfusion values were calculated by using a modified deconvolution-based analysis, with the application of CT perfusion software. Region of interest placed over the biggest lymph node was found in a previous CT study. Postprocessing-generated maps showed perfusion (P), peak enhancement intensity, time to peak (TTP), blood flow (BF), blood volume ml/ 100ml (BV). Data were statistically analyzed with Wilcoxon sign test, and results were compared with histopathological findings. results: Histologically proven malignant lymph nodes perfusion values were significantly different from those in benign lymph nodes. The mean values of BF were 11.7 (± 3.1), BV was 2.7 (± 0.26) and TTP was 22 sec (± 3.9 sec). Compared to non-malignant nodes, the malignant ones showed significantly lower BF and BV values (p<0.009). The accuracy of detecting malignant nodes was 87%, sensitivity 92%, specificity 84%, positive predictive value 91.5%, and negative predictive value 75.9%. Conclusion: CTP can be a good tool in distinguishing benign and malignant lymph nodes in esophageal cancer and can increase the diagnostic accuracy.

oesophageal resection: postoperative anatomy and complications on Ct O. Bashir, K. Latief; Nottingham/UK Learning objectives: To illustrate postoperative anatomy and complications of oesophageal resection surgery as demonstrated by CT. Correlation with conventional imaging findings is also described to improve the understanding of common complications of oeophageal resection. Background: Oesophageal resection is performed for both benign and malignant oesophageal conditions. This procedure is associated with significant morbidity and CT is frequently undertaken to diagnose complications and disease recurrence. Imaging findings or procedure details: Routine assessment with water soluble contrast swallow is carried out seven days after oesophageal resection surgery at our institution. This allows for the early detection of anastomotic leaks. Additionally, certain complications of major thoracic surgery such as atelactasis and pneumonia can be seen on plain chest radiographs. However, several complications of oesophageal resection including ARDS, empyema, diaphragmatic hernia and disease recurrence are best demonstrated on crossectional imaging. CT is a frequently performed investigation for the diagnosis of complications of oesophageal resection. Conclusion: Oesophagectomy is associated with a significant morbidity. CT is frequently carried out to evaluate post oesphagectomy patients. CT findings of various post oesophagectomy complications are described. An understanding of postoperative anatomy and pathology is crucial for the accurate diagnosis of complications and helpful in guiding patient management. 

Upper gastrointestinal tract due to foreign bodies perforations: diagnostic pathway P. Giusti, S. Giusti, V. Morigoni, C. Bartolozzi; Pisa/IT Learning objectives: To show the pathognomonic oesophagogastric digital fluoroscopic findings detected in case of oesophageal perforations in order to early diagnose them and to plan the proper and resolutive therapy. Background: We reviewed the radiological findings from 14 patients who have accidentally ingested foreign bodies causing oesophageal perforation. Different agents may be responsible for these rare but severe conditions. In our experience, we studied very singular ingestions as chickenbone, fishbone, small toys and perforations due to iatrogenic injuries. Imaging findings or procedure details: All cases have been approached with a conventional radiography of the chest, followed by an oesophagogastric digital fluoroscopic study performed in emergency with high frame velocity (3/sec), during oral administration of iodinated contrast medium. When necessary, we completed our conventional examination with MDCT scans useful for identifying more exactly contrast medium spreadings. Radiological findings identified with conventional techinque were: irregularity of oesophageal wall, fat stranding, contrast spreadings, pneumomediastinum, and broncho-oesophageal fistulas. The clinical features of OP are often non-specific and radiological imaging is essential to achieve early diagnosis and reduce mortality. Knowledge of the usefulness of various imaging modalities, the radiological features of OP, and of management options is crucial to achieve accurate diagnosis, interpret follow-up studies, and guide management. Imaging findings or procedure details: Recognition of the features of OP on an initial chest X-ray guides the use of specific imaging techniques, including luminal contrast studies, computed tomography (CT), and CT esophagography in the initial diagnosis and follow-up of this condition. We discuss the advantages and limitations of these imaging modalities and the radiological features of OP and its complications. We discuss the surgical and interventional radiology management options and illustrate their appearances on follow-up imaging studies. Conclusion: OP is a life-threatening condition. Knowledge of the radiological features of OP and its complications, the advantages and limitations of various imaging modalities, and the treatment options is crucial to achieve accurate diagnosis, interpret follow-up studies and guide management. To highlight the importance of using the correct nomenclature for disease staging and treatment planning. Background: The combination of PET-CT and MDCT has revolutionised the staging and management of upper GI tumours. These tumours commonly spread to lymph nodes. The precise location of the involved lymph node is essential for the correct stage. For example, in lower oesophageal cancer, a gastrohepatic ligament node is considered a local N1 node. However, a coeliac axis lymph node is upstaged as M1a disease. Imaging findings or procedure details: The lymph node stations will be demonstrated using illustrations and cross sectional images. The potential pitfalls that can incorrectly stage the patient will be highlighted.

A common understanding of the precise anatomic position and terminology used by the radiologist and the surgeon is important for correct staging and surgical treatment planning. Imaging findings or procedure details: We illustrate a spectrum of direct and indirect signs of mesenteric and bowel wall injury and associated findings in the trauma setting. The direct signs include bowel wall defect, extraluminal air and extravasation of oral contrast material. The indirect signs are non-specific but their presence is suspicious for BI and include diffuse or isolated wall thickening, intramural air, abnormal bowel wall enhancement, free fluid and adjacent mesenteric hematoma. MDCT imaging patterns were correlated with surgical findings on a patient-by-patient basis. Conclusion: Knowledge and recognition of trauma-related mesenteric and BIs on CT is essential for the correct management of haemodynamically stable patients to avoid mortality and morbidity of delayed diagnosis. Imaging findings or procedure details: The role of MR and MDCT in defining mesenteric disease will be discussed. Explanations of normal anatomy will be given with the aid of diagrams and cross-sectional imaging. Pathologies illustrated include inflammatory processes such as sclerosing mesenteritis, primary neoplasms (e.g. desmoid tumours and mesothelioma), secondary tumours, infective processes and ischemia. Pathologies can also be subdivided according to their imaging appearances, which include ill defined/infiltrative processes, cystic masses and solid lesions. Conclusion: It is important for abdominal radiologists to have a thorough understanding of mesenteric anatomy and pathology. The imaging appearances on cross-sectional imaging aid in forming a diagnosis, especially when knowledge of the various patterns of disease are applied. unusual manifestation. We describe the imaging findings of a wide spectrum of GISTs with an emphasis on unusual findings and pathologic correlation. Imaging findings or procedure details: CT imaging of small GISTs typically show round and homogeneous low-density intramural mass with intact overlying mucosa, but necrosis, cavity formation and exophytic growing pattern are commonly noted in large GISTs. Calcification, cystic necrosis in small GIST, circumferential mural thickening pattern mimic lymphoma, extra-gastrointestinal GISTs, and atypical findings of hepatic metastasis are unusual radiologic findings of GISTs. Conclusion: Radiologic findings of GISTs are various, so it is important that radiologists are familiar with these findings. An awareness of the various radiologic manifestations in GISTs can help ensure a correct diagnosis and proper management. Classically upper GI series were the method of choice, but CT has an increasing role in the evaluation of these cases. Imaging findings or procedure details: In acute setting, chest and abdominal radiographs are performed looking for signs of perforation. Acute-subacute lesions can be seen as atony, dilatation, sloughing and irregular contours, thickened and irregular folds and ulceration in upper GI series. CT can depict more accurately the extension of mural lesions and extradigestive findings. These radiographic findings reflect mucosal destruction and intramural edema and/or hemorrhage. Chronic lesions are mainly single or multiple stenosis associated with various degrees of obstruction. Rigidity and lack of mucosal relief are other signs which correlate with fibrotic changes and cicatrisation of the lesions.

Radiological studies may provide valuable information during both the acute and the chronic stages of caustic GI injuries.

Withdrawn Imaging findings or procedure details: Abdominal manifestations affect multiple organ systems. Nearly the entire digestive tract is affected in patients with CF and GI complications include gastroesophageal reflux and peptic ulceration, meconium ileus with associated complications during the neonatal period, distal intestinal obstruction syndrome, intussusception, appendicitis, fibrosing colonopathy, pneumatosis intestinalis, rectal mucosal prolapse, pseudomembranous colitis and malignancy. Hepatobiliary complications include gallbladder disease, fatty infiltration of the liver, bile duct abnormalities, focal biliary fibrosis and multinodular cirrhosis and associated portal hypertension. Pancreas involvement may result in acute pancreatitis, fatty replacement, calcification, cysts, duct abnormalities and carcinoma. We provide a pictorial review of the imaging findings. Thessaloniki/GR, 2 Ankara/TR Learning objectives: MP is a chronic, tumor-like, aseptic inflammatory process of the adipose tissue of the mesentery. Although MP is a rather rare condition, the use of abdominal CT as well as the awareness of modern radiologists about this pathology and its specific signs has made the diagnosis more frequent. The objective of our study was to describe the specific signs of MP with CT. Background: We retrospectively evaluated 1500 abdominal CTs of adult patients (between ages 51 and 85) that were performed over a period of 5 years in our department. Patients with ascites, abdominal trauma, malignant tumors of the pancreas and pathology of the lymphatic system were excluded. Imaging findings or procedure details: In our study, 45 of the abdominal CTs showed signs of mesenteric panniculitis (MP) (3%). The characteristic CT signs of MP are: hyperattenuation of the mesenteric adipose tissue was observed in 100%, "fat-halo" sign in 60%, nodules (diameter <10 mm) in 84.4%, and pseudocapsule in 18%. The exact etiology of the disease is not known. Yet studies have suggested that MP consists of a paraneoplasmatic response. Conclusion: Abdominal CT is the radiologic method of choice for the diagnosis of MP. Although MP is usually asymptomatic and does not require therapy, its early diagnosis is necessary because according to recent literature it is regarded as a paraneoplasmatic condition. Background: Abdominal lymphoma has a wide variety of imaging appearances and definitive diagnosis relies on histopathologic analysis. CT has been shown to be useful to define the extent of disease, assist in treatment planning, evaluate the response to therapy and monitor patient progress and possible relapse. Imaging findings or procedure details: In this exhibit, we describe and illustrate: 1. The CT technique, appearance and implications of imaging findings for disease management in patients with lymphomatous involvement of the: 1. It also provides adequate evaluation of intra-abdominal organs, frequently leading to a specific diagnosis. Additionally, it establishes gas extension and precise anatomic location, aiding in therapeutic decision making. Imaging findings or procedure details: We describe CT imaging spectrum of extraluminal gas on the abdomen, often with correlative abdominal radiographs or CT topograms. The radiological diagnoses were confirmed by reviewing clinical, pathological and surgical records. We illustrate spurious, iatrogenic, traumatic, infectious, isquemic and neoplastic conditions that are depicted by pneumoperitoneum, emphysema, pneumatosis, portomesenteric venous gas, pneumobilia and abscesses, valuing its pathologic and clinical correlation. Helpful hints for differential diagnosis and features with therapeutic relevance are also stressed out. Conclusion: CT is the most accurate technique for imaging extraluminal abdominal gas and has diagnostic and therapeutic impact. Imaging findings or procedure details: Imaging features of GI tract diverticular disease listed in the Learning objectives: will be discussed. The role of conventional GI studies and CT for the diagnosis of sympatomatic diverticular disease will be highlighted. Acute and chronic complications associated with various common and uncommon diverticula will be outlined. Conclusion: Apart from colon, diverticula may arise from any segment of the GI tract. Symptomatic diverticular disease warrants imaging with contrast GI studies or CT. Imaging allows for definitive diagnosis of symptomatic diverticular disease and can further characterize complications, thereby directing management. Learning objectives: a) To discuss the use of diagnostic imaging in the diagnosis of acute and chronic diaphragmatic injuries. b) To discus some more subtle signs of diaphragmatic injuries which require careful analysis of CT images and examination with MRI in specific situations. Background: Traumatic rupture of the diaphragm may result from blunt or penetrating injuries. Unilateral hemi diaphragm injury is more common with injuries to the left hemi diaphragm occurring three times more frequently than the right. Various imaging modalities including chest radiography, CT and abdominal US may be used for diagnosis of diaphragmatic injury. Imaging findings or procedure details: This poster will utilise a number of interesting examples which illustrate imaging findings of traumatic diaphragm rupture/herniation in the acute and chronic settings. We will focus on the role of CT and advantages of multiplanar reconstruction. We will also illustrate common and unusual complications of acute and chronic diaphragm rupture. Conclusion: Various radiological modalities are necessary to make an accurate diagnosis of diaphragmatic injury and CT currently is the modality of choice. A high index of suspicion within the appropriate clinical setting should be maintained to allow correct diagnosis. Early diagnosis and repair prevent potentially devastating complications that result from visceral herniation through the post-traumatic diaphragm defect.

mdCt in the acute abdomen from small bowel obstruction: criteria for diagnosis of ischemia with correlative surgical findings S. Romano, P. Lombardo, T. Cinque, G. Bartone, L. Romano; Naples/IT Learning objectives: To attest the essential role of MDCT in small bowel obstruction imaging, regarding the evaluation of the site of obstruction versus the various stages of disease, especially concerning the irreversible ischemic complications. Background: Small bowel complicated obstruction with ischemia is an important event reporting high mortality rate if the diagnosis is too late, that is when infarction of the intestine is confirmed. The usefulness of MDCT in diagnosis of site and cause of an intestinal obstruction is already known in the scientific literature; however, less has been described regarding criteria for specific diagnosis of an ischemia caused by advanced degree of intestinal obstruction. Imaging findings or procedure details: Our work is based on a retrospective evaluation of the emergency MDCT imaging findings of a large adult patient population with proven small bowel obstruction. All examinations were performed after i.v. contrast material administration, without endoluminal opacification. Correlation between the surgical results and the imaging findings (small bowel dilatation, transition point evidence, suggestive or evident cause of obstruction, presence and extension of alterations in bowel wall enhancement) was made in all cases. Conclusion: Various degrees of wall thickening and mural enhancement were listed and correlated with the definitive diagnosis of complicated small bowel obstruction by intestinal ischemia. Advanced ischemia and infarction have been mostly observed in patients with volvolus.

multi-detector-row Ct of mesenteric ischemia: a metaanalysis of the literature L. Saba, G. Mallarini; Cagliari/IT purpose: The aim of this work was to evaluate the diagnostic efficacy of multidetector-row CT (MDCT) in the study of mesenteric ischemia and to identify the radiological signs that allow for making diagnosis. We performed a meta-analysis of the literature by evaluating sensitivity, specificity and diagnostic efficacy of MDCT. We evaluated also the impact produced by the newest CT scanner in the bowel ischemia diagnosis. material and methods: A comprehensive analysis of the literature was performed by using the medical literature database of PubMed and Cochrane as data sources. We searched for articles published in English language from January 1998 to October 2007. results: Our search results detected 24 studies that met the inclusion criteria of the 112 overall analyzed. We observed that MDCT sensitivity increased by using postprocessing procedures such as MPR and MIP. The most frequent pathological signs described were intramural pneumatosis, bowel wall thickening, mesenteric arterial or venous thromboembolism, halo sign and mesenteric or portal venous gas. Conclusion: Results of our study suggests that MDCT is an optimal technique to study patients with suspected mesenteric ischemia because it offers high sensitivity in detecting radiological v signs of mesenteric ischemia. In particular, the use of MDCT angiography is very effective in the evaluation of abdominal vessels, giving the opportunity of a better definition of vascular map and its complications. Four scans revealed dilated small bowel loops containing faeces in keeping with distal intestinal obstruction syndrome. Thickening of small and large bowel wall was observed in four cases. In two of these, there were associated peri-enteric fibro-fatty proliferation and lymphadenopathy, a pattern mimicking Crohn's disease, but not histologically proven in either case. Of the remaining, there were four cases of intussusception and one case of chronic pancreatitis with peripancreatic collection. Conclusion: A spectrum of CF related gastrointestinal causes requiring different management strategies was observed on CT. An appreciation of these causes is important for the radiologic assessment and management of adult CF patients presenting with abdominal pain.

High density enteral contrast for Ct demonstration of site of post-operative leaks G. Alluvada, A. Razack; Hull/UK Learning objectives: HDC is better for demonstration of post-operative leaks and should be used in the first instance to avoid repeat examinations. Background: Oral contrast at dilutions of 2 to 5% is traditionally used to outline bowel in abdominal CT scans. This, however, is not dense enough to confidently identify the site of enteral leaks. Presence of free air is used to assess for leaks; however, this is fraught with difficulties of interpretation in post-operative patients. Imaging findings or procedure details: We used high density contrast (HDC) at concentrations of 20-25% to identify the presence and site of post-operative leaks. We present imaging findings of six cases of post-operative enteral leaks. We performed CT scans for suspected enteral leaks with HDC (Iopamidol 300 mgI/ml, 100 ml diluted in 400 ml of water) as opposed to 3% (Urograffin 150 mgI/ml, 30 ml in 800 ml of water) contrast used in our hospital. Four patients had previously undergone CT with 3% urograffin and the presence and site of leak could not be demonstrated which was essential for their management. CT with HDC demonstrated the presence and site of leaks which was confirmed at surgery. Conclusion: HDC is very useful in demonstrating the actual site of the postoperative leaks. This does not cause streak artefacts in MDCT scanners and in our experience has no disadvantages. We recommend the use of HDC for patients with suspicion of post operative leaks.

abdominal X-rays and outcomes N. Jagirdar 1 , M.H. Thoufeeq 2 , A. Haroon 1 , R. Jones 3 ; 1 Leicester/UK, 2 Hull/UK, 3 Boston/UK purpose: We wanted to assess if Royal College of Radiologists (RCR) UK guidelines on requesting abdominal X-rays were followed at our hospital. material and methods: A retrospective study looking at patients who had abdominal X-rays done in late 2006 looking at their clinical notes, X-ray requests, final outcomes and reports. results: 96 patients had abdominal X-rays done during this period. The patients' ages were between 18 and 94, median being 58. Their presenting complaints were abdominal pain in 74%, vomiting 9%, loin pain 5%, and collapse 4%. Haematemesis, rectal bleeding, constipation, chest pain, urinary retention, confusion and drowsiness formed 1% each. On looking at the clinical notes, we found constipation in 10%, ureteric colic 10%, possible abdominal aortic aneurysm rupture in 10%, biliary colic 4%, appendicitis 4%, haematemesis 3%, and possible perforation 3%. 9% had non-perforation type abdominal pain, urinary retention 2%, retroperitoneal abscess and strangulated hernia 1% each. 35% had other medical conditions. 76% were admitted, 22% discharged and 2% patients died. 85% were reported normal, 5% as faecal loading, ureteric stones and pheleboliths as 3% each, 2% as calcified abdominal aortic aneurysm and 1% as subacute intestinal obstruction.

We noted that RCR guidelines were not followed. Abdominal X-rays did not change patient management in majority (95%) of our cases and expose patients to unnecessary radiation.

Very rare cases of variable foreign bodies in the GI tract or abdomino-pelvic cavity J. Chung, J. Yu, J.H. Kim; Seoul/KR Learning objectives: 1. To know the plain radiological findings of the very rare foreign bodies introduced into the gastrointestinal tract or abdomino-pelvic cavity. 2. To understand the plain radiographic and CT findings according to the materials of foreign bodies, such as glass bottle, plastic bottle, and metal. Background: On daily practice, we have met the very rare cases of variable foreign bodies in the gastrointestinal tract (GIT) or abdomino-pelvic cavity. However, if it was the first time to meet the very rare foreign bodies, it was not easy to interpret those cases. Those foreign bodies can be introduced by accident, surgery, iatrogenic procedure or prank. Imaging findings or procedure details: There are 12 patients with variable foreign bodies in GIT or abdomino-pelvic cavity. Some of foreign bodies were removed by surgery, endoscopic procedure or natural defecation. Twelve cases with foreign bodies were composed as follows: 1) rectum: a plastic bottle for hair spray, a glass bottle for juice, a masturbation unit, a broken metallic stent; 2) stomach: a tooth brush, a gold tooth; 3) small bowel: a gold tooth; 4) appendix: a metallic material; 5) abdomen: an acupuncture needle traversing the abdomen, a few acupuncture needles in the peritoneal cavity, a cloth pin and 6) pelvic cavity: a thumbtack in right pelvic wall for hemostasis during operation for rectal cancer.

Conclusion: This exhibition shows 12 cases of very rare, variable foreign bodies in the GI tract or abdomino-pelvic cavity.

Cisterna The abdominal confluence of lymph trunks, the so called cisterna chyli, is a dilated lymphatic sac in the retrocrual space and is located at the origin of the thoracic duct. It receives the lymph mainly from bilateral lumbar trunks and the intestinal trunks. The cisterna chyli can be involved in various diseases, such as heart failure, liver cirrhosis, and gastrointestinal tumors. Knowledge of the CT imaging of normal and pathological conditions is clinically important. Recently, thin-slice images using multi-detector row CT (MDCT) allow the CT anatomy of the cisterna chyli, but there are no reports evaluating the cisterna chyli using MDCT. Imaging findings or procedure details: In this education exhibit, we will demonstrate the normal CT anatomy of the cisterna chyli obtained by imaging reconstruction every 1 mm with multiplanar reformation using MDCT. Furthermore, we will review the CT imaging of the cisterna chyli in pathological conditions. Conclusion: Thin-slice images using MDCT can clearly depict the cisterna chyli in normal and pathological conditions. 

mdCt imaging findings in peritoneal carcinomatosis L. Saba, G. Mallarini; Cagliari/IT Learning objectives: The purpose of this work is to understand the pathogenesis of peritoneal carcinomatosis according to the primitive causes and to review clinical, pathologic and radiological manifestations of peritoneal carcinomatosis. Background: Peritoneal carcinomatosis refers to a wide variety of tumors that present with extensive peritoneal involvement with or without parenchymal involvement of solid organs such as the liver, spleen and lymph nodes. It is a common evolution of cancers of the digestive tract such as stomach, small bowel, colon rectum, appendix and pancreas. Other tumors that may lead to these conditions include ovarian, mesothelioma, sarcoma and pseudomyxoma peritonei. In the last decade, CT has significantly altered the diagnostic approach to peritoneal carcinomatosis influencing also the therapeutic approach in the current practice. Imaging findings or procedure details: In this work, we describe and show several MDCT imaging findings of peritoneal carcinomatosis including parietal peritoneal thickening, tumor involvement of the omentum (soft tissue permeation of the fat, enhancing nodules, and omental cake) and ascites. We include several examples by using MDCT source axial images and post-processing techniques as Multi-planar Reconstruction (MPR), Maximum Intensity Projection (MIP) and Volume Rendering (VR). Conclusion: Peritoneal carcinomatosis shows a broad spectrum of radiological manifestations and sometimes may simulate other neoplastic and inflammatory conditions and so it is mandatory for a tight integration between radiological, anamnestical and clinical signs. Imaging findings or procedure details: Anatomical imaging, dual phase contrast CT and MRI including post gadolinium determines site and size, whereas functional imaging with In111-Octreoscan enables receptor density of somatostatin receptor type 2 and 5 to be determined. We present illustrative cases with characteristic images from different imaging modalities to reveal the advantages and necessity of multidisciplinary approach for diagnosis and management of carcinoids. Conclusion: MDT approach improves results in appropriate management of patients with carcinoid tumours. The combination of anatomical imaging with functional imaging is recommended in making crucial management decisions.

Variation material and methods: A study was made of 159 persons whose abdominal CT was taken before surgery (90 stomach cancers, 69 colon cancers). Body fat volume was automatically extracted using a Philips EBW2. Body fat was classified into total abdominal fat (TAF) and visceral fat (VF). The average ratio of fat change between the two cancer groups was compared using a t-test. The stomach cancer group was divided into subtotal gasrectormy (SG) and total gastrectomy (TG), and the average ratio of fat between SG and TG were also compared. results: The TAF and VF ratios of post-surgeries against pre-surgeries regarding stomach cancer were 0.94±0.48 and 0.77±0.37, respectively, and those for the colon cancer group were 1.32±0.6 and 1.29±0.76, respectively. There was a noticeable statistical difference between stomach and colon cancers (p=0.000). 60 of stomach cancer patients had SG, and 30 had TG. The TAF and VF ratios for SG were 1.03±0.48 and 0.85±0.38, respectively, and those of TG were 0.77±0.43 and 0.62±0.31, respectively. There was a noticeable difference between SG and TG (p<0.01).

The stomach cancer surgery group showed a significant reduction of body fat when compared with colon cancer. The TG in particular showed a significant reduction of body fat. Therefore, great caution should be taken when making node evaluations on CT after stomach cancer surgery due to reduced visceral fat. 

Withdrawn by authors

Ct findings of lymphma with peritoneal, omental and mesenteric involvement: pertioneal lymphomatosis D. Karaosmanoglu, M. Karcaaltincaba, D. Akata, M.N. Ozmen, O. Akhan; Ankara/TR purpose: We investigated CT findings in patients with peritoneal, omental and mesenteric lymphoma involvement. material and methods: We searched our archive retrospectively to find out patients with peritoneal, omental and mesenteric lymphoma involvement. We found 16 patients with non-Hodgkin lymphoma meeting these criteria. CT studies of these patients were reevaluated for presence of peritoneal involvement, ascites, omental mass, organomegaly, retroperitoneal lymphadenopathy, bowel wall thickening and other associated findings. results: There were 14 males and 2 females with peritoneal and/or mesenteric and omental lymphoma involvement. Mean age was 39 (range 4-76). Subgroups of non-Hodgkin lymphoma were diffuse large B-cell lymphoma (n=11), small cell lymphocytic lymphoma (n=2), small cleaved cell lymphoma (n=1), T-cell lymphoma (n=1) and Burkitt`s lymphoma (n=1). Peritoneal involvement was seen in 15 (94%) patients in the form of linear (n=12) and nodular (n=3) thickening. Ascites was seen in 12 (75%) patients. Omental and mesenteric masses were present in 10 (66.6%) and 10 (66.6%) patients, respectively. Bowel wall thickening, retroperitoneal lymphadenopathy and hepatosplenomeagly were also common and observed in 10, 10 and 11 patients, respectively. Solid organ involvement in form of liver and splenic lesions was seen in 9 (56%) patients. Conclusion: Peritoneal involvement can be seen in many subtypes of lymphoma and most frequently in diffuse large B-cell lymphoma. Peritoneal lymphomatosis can mimic peritoneal carcinomatosis and should be included in differential diagnosis list in patients with ascites, hepatosplenic lesions and unidentified cause of peritoneal thickening on CT in a male patient.

Withdrawn year-old patient with suspected NEC in the mesentery was referred for CT evaluation. A 320-slice dynamic volume CT was performed using a dynamic scanning protocol involving 17 low-dose acquisitions spread over a total of 40 seconds. Images were registered centered on the tumour for motion correction, and perfusion maps were generated based on the multiple acquisitions. Bowel motion was visualized by means of a movie generation. results: The tumour in the mesentery showed a clearly different perfusion pattern compared to the surrounding tissue. The extent of bowel infiltration was diagnosed by means direct morphologic visualization and through demonstration of motion restriction of the infiltrated small bowel loops. Based on the perfusion findings, surgical resection was performed confirming the extent of infiltration. Conclusion: Perfusion imaging of the mesentery may provide valuable information and carries the potential to direct patients to tumour surgery. Image registration appears mandatory for calculation of perfusion maps.

multidetector-row Ct: how to avoid the misdiagnosis of appendicitis? A. Filippone, R. Cianci, S. Valeriano, M.L. Storto; Chieti/IT purpose: To establish potential causes of misdiagnosis in patients with surgically proven appendicitis not detected on multidetector-row CT (MDCT). material and methods: CT scans of 21 patients with surgically proven acute appendicitis incorrectly diagnosed on the preoperative MDCT were reviewed in consensus by two experienced abdominal radiologists who had knowledge only of a possible diagnosis of acute appendicitis. Readers were asked to record the following: visualization of the entire appendix, the maximal appendiceal diameter greater than 7 mm, thickening of the appendiceal walls, periappendiceal inflammatory changes, presence and location of fluid collection and/or gas bubbles. Any other abnormal CT finding was recorded including small bowel obstruction and diverticulosis. The degree of intraabdominal fat content according to a subjective scale (1-minimal; 2-moderate; 3-marked) as well as technical factors potentially responsible of misdiagnosis were also considered. results: Only 7/21 patients presented marked amount of intraperitoneal fat. Intravenous contrast material was administered in 9/21 patients. In 3/21 patients, most of the appendix appeared normal since only a small portion of the distal appendix was involved. Appendiceal inflammation resulted in small bowel obstruction in 5/21 patients and was confused with gynaecological disease or complicated diverticulitis, expecially when perforation was present.

Conclusion: Suboptimal CT studies, tip appendicitis, atypical presentation of appendiceal inflammation may lead to misdiagnosis of appendicitis at MDCT. Knowledge of these pitfalls enables us to improve our diagnostic accuracy.

Withdrawn by authors Histopathologic staging was considered as gold standard. All the initial T staging mentioned in the radiology reports were recorded and accuracy was calculated. All the MRI scans were then restaged by two gastrointestinal radiologists who were blinded to the initial staging and final histopathologic staging. Accuracy was calculated for double reporting. results: Of the 46 patients who had MRI surgery, the initial staging accuracy for T staging was 54%. Ten patients were overstaged and 8 were understaged. The staging was equivocal in three patients. Twenty five patients were correctly staged. Double reporting in consensus improved the staging accuracy to 92%. Conclusion: Double reporting of MRI scans for staging of rectal cancer significantly improves the accuracy of staging. 

severe constipation and pelvic floor disorders: evaluation with colon transit time and dynamic digital colpo-cystodefecography P. Giusti, S. Giusti, F. Cerri, V. Morigoni, G. Naldini, C. Bartolozzi; Pisa/IT Learning objectives: To show the accuracy of CTT and ddCCD in pts with severe constipation and clinically suspected pelvic floor dysfunction. Background: We reviewed the findings from dynamic digital colpo-cystodefecography (ddCCD) and colon transit time (CCT) in 134 women examined within a 4-years time period. Each patient was given 400 mL of 60% density barium to opacify the small bowel; the bladder was filled with 200 mL of an iodinated contrast medium; the vagina was opacified with a tampon soaked in an iodinated contrast agent; and the rectum was filled with 200 mL of a high density barium suspension. CTT was documented with an abdominal plain, since patients have ingested 24 markers up to 5 days. Imaging findings or procedure details: Abnormal findings revealed by CTT (CTT+) were present in 92 pts (68.6%), while in 42 pts (31%) all markers were evacuated within 5 days (CTT-). Comparing these different groups with ddCCD, we detected: anterior rectoceles (34 pts with CTT-; 68 pts with CTT+), intussusception (36 pts with CTT-; 88 pts with CTT+), pubo-rectal muscle hypertone (6 pts with CTT-; 6 pts with CTT+); reduction of ano-rectal angle (11 pts with CTT-; 15 pts with CTT+). In 45/134 pts ddCCD revealed an enterocele, in 23/134 a cystocele. Conclusion: Constipation is often associated with compartment defects in pelvic floor and moreover this chronic syndrome is due to anomalies of anorectal region rather than an impairment of colonic motility. To opacify the small bowel patients (pts) were ingested 400 mL of 60% density barium suspension; the bladder was then opacified by the administration of 300 mL of an iodinate contrast medium, and the rectum was filled with 200 mL of a high density barium suspension. Imaging findings or procedure details: The dynamic digital colpo-cystodefecography (ddCCD) examination revealed the presenece of an anterior rectoceles associated with a severe intussusception in 52/55 pts, enterocele in 22/55 pts, sigmoidocele in 8/55 pts, rectal prolapse in 19/55 pts, and cystocele in 4/55 pts. All pts underwent surgery to resolve the above mentioned pelvic floor dysfunctions. The presence of enterocele, sigmoidocele and/or cystocele required a different surgical approach respect to those pts who presented only with anorectal disorders.

The ddCCD examination allows determining the presence of associated urinary, genital and anorectal abnormalities in women with pelvic floor dysfunctions in order to preoperatively plan and optimize the proper surgical repair. Background: Rectal carcinoma is a common cause of cancer death in Europe and the United States. Its prognosis is related to the extent of extramural spread into the mesorectum at the time of diagnosis, and to the ability to achieve surgical clearance at the circumferential resection margins. We describe the phasedarray MR TNM features of rectal cancer, before and after neoadjuvant chemoradiation therapy showing the corresponding histopathological slices. Imaging findings or procedure details: All patients underwent MR staging at time of diagnosis and again prior to surgery for restaging of disease. We acquired axial and sagittal T2wi. Sagittal images were used to plan large FOV axial sections useful to evaluate the whole pelvis, from the iliac crest to the symphisis pubis, and again to plan high-resolution 3-mm-section axial images, acquired perpendicularly to the long-axis of the rectal tumour and performed by using a smaller FOV. Conclusion: Phased array MRI is an excellent technique to preoperative local stage rectal carcinoma allowing to: evaluate mesorectum and pelvis; plan surgery, optimizing a complete excision; decide about the use of neoadjuvant therapy in order to downstage lesions and to perform a sphincter-preserving surgery in those pts who otherwise would require colostomy. it provides information about cell organization and density, microstructure, and microcirculation of tissue. In the intracellular area, diffusion is relatively slow, whereas diffusion is relatively fast in the extracellular area. Tissue diffusion variations can be assessed by the construction of diffusion maps and quantitative estimations that reflect by the apparent diffusion coefficients (ADCs). Diffusion maps provide images with improved signal-to-noise ratios; reversal of the contrast of these images resulted in black-and-white images. Diffusion maps have substantial implications for diagnosis, targeting of focal treatments and measuring treatment responses. Low ADC values may indicate malignancies or hypercellularity. Therefore, quantitative DW-MRI may allow the cellularity of tumors to be graded noninvasively and assessment of early tumour's therapy response.

Conclusion: DW-MRI appears to have great promise for increasing our understanding of rectal tumors and the effects of therapy.

the utility of mdCt perfusion examination in detection of metastatic lymph nodes of rectal cancer L. Tóth, G. Tóth, E.C. Turupoli, Z. Vígváry; Budapest/HU purpose: Assessment of the role of computed tomography perfusion (CTP) study for the differentiation between malignant and benign enlarged perirectal, pelvical, and retroperitoneal lymph nodes. material and methods: A prospective study was conducted on a 21 consecutive patients (12 M, 9 F aged 45-72) with a histologically proven rectal cancer. The perfusion study was done after contrast-enhanced conventional abdomonal MDCT study. A dynamic acquisition (8x3 mm slices) was performed and the perfusion values were calculated using a modified deconvolution-based analysis, with the application of CT perfusion software. Region of interest placed over the biggest lymph node was found in a previous CT study. Postprocessing-generated maps showed perfusion (P), peak enhancement intensity (PEI), time to peak (TTP), blood flow (BF), blood volume ml/100ml (BV 

Ct CT features of these uncommon tumors of the rectum may overlap with rectal carcinoma. However, with recent advances of helical CT or MDCT, the CT features with pathologic correlation of various uncommon or rare tumors of the rectum may help narrow differential diagnosis. Imaging findings or procedure details: We retrospectively reviewed the CT features with pathologic correlation in 20 patients with surgically or pathologically proven uncommon tumors of the rectum. Helical CT or 16-MDCT imaging was obtained during the arterial and portal venous phases. Uncommon or rare tumors of the rectum were GIST (n=5), neuroendocrine tumors (n=4), metastasis of linitis plastica pattern from gastric cancers (n=3), lymphomas (n=2), melanomas (n=2), cloacogenic cancers (n=2), papillary cystadenocarcinoma of the mesorectum (n=1), and malignant fibrous histiocytoma (n=1). Conclusion: Familiarity with the CT features and pathologic correlation of various uncommon or rare rectal tumors can help ensure differential diagnosis and proper management. 44 .2% had impaired defecation; 9.6% showed incontinence; the remaining had normal defecation duration and efficacy but with associated dynamic and morphologic changes. Results are discussed, including prevalence of defecation disorders: significant perineum descent (76.9%); rectocele (67.3%); rectal intussusception (61.5%); non-relaxing pubo-rectalis (50%); anal dysfunction (34.6%); and rectal prolapse (7.7%). Challenging examinations are also exhibited. Conclusion: Defecography is a well-tolerated, easily feasible, valuable method with great cost-benefit ratio in the evaluation of defecation disorders. It is important that radiologists and clinicians understand this dynamic procedure, which is becoming increasingly requested and is central in the management of defecation disorders. 

Comparison of preoperative mdCt and mrI for the assessment of circumferential margin infiltration in rectal cancer: preliminary data J.R. Ayuso To provide an overview of the diagnostic imaging modalities of OGIB including double balloon enteroscopy, wireless capsule endoscopy, MDCT, angiography, and bleeding scanning with labeled red blood cells. Background: Obscure gastrointestinal bleeding (OGIB) is defined as an intermittent or continuous loss of blood in which the source has not been identified after upper endoscopy and colonoscopy. Whether an obscure site of bleeding is clinically evident by obvious symptoms or signs, or silent and manifest only as refractory iron deficiency anemia, it constitutes a diagnostic and therapeutic challenge for the clinician. Gastroenterology and radiology provide the essential diagnostic imaging modalities in OGIB, each one with its strengths and weaknesses. Imaging findings or procedure details: Through case illustration, the authors will discuss the role, indications, advantages and limitations of double balloon enteroscopy, wireless capsule endoscopy, MDCT, angiography and bleeding scanning with technetium 99m-labeled RBC in the evaluation of the patient with OGIB. Conclusion: Recognition of the cause and site of GI bleeding is instrumental to guide treatment planning. Gastroenterological and radiological imaging approaches should be tailored according to the clinical scenario.

Comparison of perfusion mdCt results with Crohn's disease activity index G. Tóth, L. Tóth, E.C. Turupoli, V. Bérczi; Budapest/HU purpose: The purpose of this study was to evaluate the utility of perfusion MDCT in predicting the activity of Crohn's disease. material and methods: We examined 48 patients with known Crohn's disease. These patients had thickened wall small or large bowel segment. 32 patients had clinically suspected exacerbation of Crohn's disease. Methycellulose solution was administered for small bowel distension. Region of interest were placed over the most thickened segment of small or large bowel. In this level, we measured the perfusion of the wall and adjacent mesentery. We administered 1.5 ml/kg i.v. contrast material. The flow was 3.5 ml/s. Acquisition started after 20 sec of administration of the contrast material and lasted for 45 sec at a rate of one image per 1.5 sec. Collimation was 8x3 mm. The slope of enhancement, perfusion (P) ml/100ml/min, peak enhancement intensity (PEI), time to peak enhancement (TTP), and blood volume (BV) ml/100g were determined. These results were compared with CDAI. Statistical analysis was performed using the Wilcoxon rank sum test. results: The signal intensities of the perfusion scans were measured and displayed in a graph. The graphs showed a typical enhancement pattern in patients with CDAI higher than 350. A good correlation was found between CDAI and P, TTE and BV (0.902, 0.932, 0.954), p<0.008. Conclusion: Perfusion CT can be valuable tool in assessing Crohn's disease activity.

setting up a Ct enteroclysis service: a practical guide A.J. Phillips, G. Whitmarsh; Bath/UK Learning objectives: To highlight the practical issues involved in setting up and maintaining a successful and efficient CTE service. Background: In recent years, CT Enteroclysis (CTE) has emerged as a promising technique for the investigation of small bowel disease. However, the widespread use of CTE has been limited by concerns over the acceptability of the technique to patients, radiologists and radiographic staff. The main issues are the invasiveness of the technique, ease of achieving consistent technical success, time constraints of pressurized CT lists and demand on radiologist's time. A number of simple practical steps can improve the acceptability and efficiency of this valuable means of imaging the small bowel. Imaging findings or procedure details: We discuss the practical issues involved in setting up and maintaining a successful and efficient CTE service. These include: 1) Careful patient selection, patient information and preparation, choice of enteroclysis catheter and use of conscious sedation to improve patient acceptability; 2) Choice of enteral contrast media, infusion techniques and CT parameters to achieve optimal small bowel visualization and 3) Organization of examinations to maximize workflow efficiency. Conclusion: CTE is a valuable tool for the investigation of small bowel disease. Attention to a number of simple practical steps may improve the acceptability and efficiency of this technique, and result in a successful CTE service. The aim of this study is to present the contributions of the TUS and MS-CT on the diagnosis and differential diagnosis of the ileocecal area pathologies based on clinical cases. Background: Ileocecal area includes the cecum, terminal ileum, ileocecal valve, and appendix. The diagnosis of the diseases in the ileocecal area is still difficult despite technological advances. The assessment of the whole segments of the GI system cannot be carried out correctly sometimes. Hence, the radiological imaging modalities gain importance in the diagnosis of the diseases in the ileocecal area. In this study, the transabdominal ultrasonography (TUS) and multi-slice CT (MS-CT) findings of the pathologies in the ileocecal area are compared and discussed with their clinical findings. Imaging findings or procedure details: Inflammatory and infectious diseases that are involved in the ileocecal area, benign-malign neoplasias, ischemic pathologies, various radiological findings such as postoperative and/or the secondary changes in the radiotherapy, important characteristic properties in the diagnosis and differential diagnosis are discussed along with clinical, histopathological information and related literature. Conclusion: Being a non-invasive technique, TUS can easily and rapidly be used in the ileocecal pathologies. It also enables the assessment of the outer-colon pathologies and their complications. 

Utility of mdCt enterography with neutral enteral and IV contrast enhancement in detection of a-V malformation E.C. Turupoli, G. Tóth, L. Tóth, V. Bérczi; Budapest/HU Learning objectives: To show the usefulness of MDCT enteroclysis in the diagnosis of A-V malformation causing GI bleeding. To show the typical CT signs of A-V malformation. Background: MDCT enteroclysis has proven to be useful for evaluating minimal bowel wall thickening and pathological dilatations of arteries and veins in bowel wall and mesentery. Our goal was to localise the focus of GI bleeding if gastroscopy and colonoscopy were negative. We present the typical imaging findings of our experience of MDCT enteroclysis. We demonstrate some of our cases. Imaging findings or procedure details: From December 2005 to January 2007, 220 CT enteroclysis were performed to investigate unexplained anaemia or GI bleeding. Positive findings were demonstrated in 35 of 220 patients. We found 6 A-V malformations, confirmed by surgery or interventional procedure. CT enteroclysis were performed using the following parameters: slice 1mm, with overlap scans, reconstruction interval 1mm, after administration of methylcellulose by nasojejunal tube, before and after infusion of 120 ml iv. contrast agent, at a rate of 4 ml/s with a scan delay of 35 seconds. In all cases, multiplanar and curved planer reformatted images were performed. Collimation was 16x0.75 mm. We studied normal appearances and pathological changes (wall thickening, pathological vessels, enhancement, extavasation, and mesenterial changes). Conclusion: MDCT enteroclysis with neutral enteral and IV contrast can be a good tool in detecting A-V malformation in small bowel.

small bowel obstruction on multidetector-row Ct: a to z J.K. Lee, S.Y. Baek; Seoul/KR 

Usefulness of the multidetector peG-Ct and enteroclysis Ct in the evaluation of the small bowel neoplasms L.M. Minordi, A. Vecchioli, P. Mirk, G. Poloni, L. Bonomo; Rome/IT purpose: To evaluate the reliability of multidetector CT (MDCT) in evaluation of small bowel neoplasms (SBN). material and methods: 120 patients with suspected small bowel disease were studied by 16 MDCT after administration of oral polyethylene glycol solution (n=56) or after administration of methylcellulose by nasojejunal tube (n=64). Unenhanced and contrast-enhanced CT were performed. Contrast-enhanced CT images were acquired 40 seconds after i.v. injection of 130 mL contrast agent at a rate of 3 mL/sec. Post-processing and multiplanar reformatting and interpretation were performed at the end of the exams. results: 15 SBN were found (6 patients with non-Hodgkin lymphoma, 3 with carcinoid tumour, 2 with Peutz Jeghers syndrome, 2 with adenocarcinoma, 2 with metastasis from melanoma, and 1 with lipoma); in the remaining cases, 58 cases of Crohn's disease and 7 other abnormalities were detected. All findings were confirmed by barium studies, surgery or endoscopy. Conclusion: MDCT with neutral intestinal contrast and IV contrast seems to be a reliable method in the diagnosis of SBNs. To write an optimal report to answer clinicians' questions.

Background: Crohn's disease is a chronic inflammatory disease involving young people. Indications and monitoring of new treatments require a more precise evaluation of disease extent, severity and activity. We propose an educational study including all imaging modalities in CD (US, MDCT, MRI, videocapsule) involving bowel, liver, and pelvic floor. Imaging findings or procedure details: Early detection relies on endoscopy and videocapsule if not contraindicated by stenosis. MDCT and MRI help in defining disease extent. MRI has a marked advantage in pelvic floor evaluation, searching for abscesses and fistulas. Whatever the imaging modality is, description has to be optimal, assessing inflammatory activity, combining morphologic abnormalities and enhancement patterns, localization and length of disease including stenosis and complications. Optimal protocols and reports will be presented in order to answer clinicians' questions for therapy and illustrated. Conclusion: The role of imaging has changed dramatically over the recent years due to technical improvement and new therapies. Acute complications seem to be best evaluated with MDCT, while MRI is a major tool for activity evaluation and pelvic examination. Disease characteristics, treatment challenges, imaging modalities advantages and limits have to be known by radiologists. 6%) and was diagnosed in the period of 12-60 months post-surgery. Plain abdominal film, GI-series, CT scans and endoscopy were used during the diagnostic process. results: Clinical findings included epigastric abdominal pain, an increase in body mass, vomiting, access port infection and gastrocutaneous fistula. However, some patients were asymptomatic and their diagnosis was established through GI-series. The pathognomonic sign of band erosion in GI-series is a flow of contrast outside the band. This sign is commonly associated with an unlikely position of the band, which appeared partially or completely inside the gastric lumen. Extraluminal air near the band is a sign of gastric wall perforation, and a fistula may be present. Conclusion: Following the initial tear, the band will slowly grow through the gastric wall and may penetrate into the lumen of stomach. The radiographic appearance of this condition is pathognomonic, and the condition will usually require a prompt surgical intervention. To understand the radiologic findings of these lesions on the basis of endoscopic and pathologic findings. 3. To describe key imaging features for the differential diagnosis of various lesions. Background: Multidetector computed tomography (MDCT) offers near-isotropic imaging of the stomach and allows more detailed evaluation of gastric morphology by high-quality multiplanar reformation and three-dimensional reconstruction of gastric images. Imaging findings or procedure details: We retrospectively reviewed the imaging findings of the various gastric non-epithelial tumors and various lesions that may mimic gastric submucosal tumors. Diagnostic pitfalls, diagnostic difficulties, and differential diagnoses are emphasized. Other imaging modalities such as EUS and endoscopic or gross pathologic findings were compared. Gastric non-epithelial tumors include leiomyoma, schwannoma, granular cell tumor, inflammatory fibroid tumor, glomus tumor, leiomyosarcoma, GIST (gastrointestinal stromal tumor), Kaposi sarcoma, malignant lymphoma, and lipoma. Other lesions that may mimic gastric submucosal tumors include carcinoid, gastric varix, ectopic pancreas, and duplication cyst. Conclusion: With this exhibit, the radiologist will have an enhanced understanding of various gastric submucosal tumors including histopathology and radiologic features. Familiarity with radiologic findings of these various lesions will make correct diagnosis possible and help the endoscopist and surgeon.

there is more to it than what meets the eye: subtle but important Ct findings in Bouveret's syndrome S. Gan, S. Roy-Choudhury, S. Agrawal, A. Pallan; Birmingham/UK Learning objectives: We aim to alert the physician to some previously undescribed signs that can help in the diagnosis of an uncommon condition. Background: Gallstones are a rare cause of duodenal or gastric outlet obstruction. It is usually diagnosed radiologically, while investigating insidious and non-specific symptoms. Rigler's triad of pneumobilia, bowel distension and an ectopic gallstone, however, is seen in very few cases of such high obstructions. Even with CT scans, 25% of cases are still misdiagnosed -often because the size of the offending gallstone is underestimated. If the size of the stone is more accurately assessed, then it is likely that fewer cases would be missed. Imaging findings or procedure details: We describe some subtle but nonetheless important CT findings that will help to better assess the size of an intra-duodenal gallstone. These include compressed air in dependant areas within the duodenal lumen, an area of soft tissue density surrounding the calcified rim of the stone, a faint lucency within or beyond this soft tissue area which could represent laminations of fat or air within the stone, and a focal distension of the duodenum proximal to the point of obstruction, indicative of an intra-luminal mass. Conclusion: It is highly unlikely that any one sign will be seen in all patients with Bouveret's syndrome, but a combination of findings should increase the likelihood of making the correct diagnosis.

the evidence base for staging gastric cancer B.G. Rock 1 , D. Buckley 2 , M. Puckett 2 ; 1 Plymouth/UK, 2 Torquay/UK purpose: Accurate staging of gastric adenocarcinoma is essential to identify patients who will benefit from radical curative surgery, spare those without prospect of cure from invasive procedures, and plan appropriate oncological/ palliative approaches. Following technological advances in diagnostic staging modalities over the past ten years, ongoing appraisal of evidence for the most appropriate staging technique is required in light of the ever-growing literature body. To illustrate the principal gastric surgery protocols, recognizing the important role of radiology in the follow-up of these patients. Background: Gastric surgery may have a place in the therapeutic approach of tumors and peptic disease, but also for morbidly obese patients. Knowledge of the surgical protocols and postoperative anatomy is essential for radiologists to be proficient in the specific evaluation of this frequent clinical condition. Imaging findings or procedure details: Bilroth I and II, gastric bypass, sleeve gastrectomy, adjustable gastric banding and biliopancreatic diversion (duodenal switch) are some of the surgical protocols presented and illustrated. Upper GI series still remain the primary radiological tool, because of a better anatomic depiction. Conclusion: Radiology plays a crucial role in the postoperative evaluation of gastric surgical procedures, both in the immediate as well as late follow-up periods. For that, the radiologist must be aware of the various techniqual approaches in gastric surgery.

Giant paraesophageal hernia with intrathoracic chronic gastric volvulus B. Baysal, C. Cimsit, H. Baysal, A. Hayirlioglu, I. Kuru, R. Yigitbasi; Istanbul/TR purpose: We report a giant hiatal hernia with intrathoracic organoaxial chronic gastric volvulus, which is an uncommon entity and describe the imaging findings through chest X-ray, upper gastrointestinal barium studies, and multidetector computerized tomography (MDCT). material and methods: A 70-year-old female was admitted to the hospital with a two month history of retrosternal pain and epigastric distention. Chest radiograms and plain abdominal radiograms were followed by upper gastrointestinal barium studies, MDCT, and endoscopy. results: The chest X-ray revealed a retrocardiac lesion with air-fluid interface. On MDCT scans, the entire stomach was displaced into the thoracic cavity and was rotated 180º along the longitudinal axis. The large diaphragmatic defect was seen on the multiplanar reconstruction CT images. The patient underwent laparoscopic repair.

The most common cause of gastric volvulus is hiatal hernias, but the principal predisposing factor is ligamentous laxity. Gastric volvulus can be classified according to its location with reference to the diaphragm and on the basis of the axis of rotation as organoaxial and mesenteroaxial volvulus. The diagnosis is radiologically suspected if air-fluid interface is seen in the chest Xray. CT provides a comprehensive intrathoracic lesion description with respect to the anatomic landmarks by means of the multiplanar imaging features. Intrathoracic organoaxial gastric volvulus may end up with complications leading to surgical emergency or may get elective treatment because of non-specific chronic symptoms.

Comparison results: Forty-five gastric cancers were found in surgical and EMR specimens. Detection rates of gastric cancer on blinded and partially blinded transverse CT and MPR images were 62% (28/45), 64% (29/45), 64% (29/45), and 71% (32/45), respectively. False detection rates on blinded and partially blinded transverse CT and MPR images were 7% (3/45), 7% (3/45), 13% (6/45), and 11% (5/45), respectively. Non-detection rates on blinded and partially blinded transverse CT and MPR images were 31% (14/45), 29% (13/45), 22% (10/45), and 18% (8/45), respectively. There is no statistical significance in comparison between blinded and partially blinded evaluation in detection rate, false detection rate, and nondetection rate of gastric cancer.

The detection rates of gastric cancer using MDCT show no specific difference between blinded and partially blinded evaluation.

Follow up Ct findings of various types of recurrence after endoscopic resection of early gastric cancer S.S. Hong, J.H. Kim; Seoul/KR Learning objectives: To review the cases of recurrence after endoscopic treatment of EGC. To analyze the missing cause on routine follow up CT. Background: When performed in carefully selected cases, the endoscopic treatment of early gastric cancer (EGC) yields results which are comparable to the conventional surgical treatment, but with lower morbidity and mortality and better quality of life. In spite of early detection and curative treatment, local or systemic recurrence can develop in various locations of the abdomen and pelvic through the several routes. In this exhibit, we will present the recurrence pattern and site, which demonstrated on follow up CT after endoscopic treatment of EGC. Emphasis lay on analysis of missed lesion which was not identified on routine preoperative CT or follow up CT, especially lymph node metastasis. Imaging findings or procedure details: The main pattern of tumor recurrence after endoscopic treatment of EGC which was presented on follow up CT was as follows: local recurrence of stomach, lymph nodes, peritoneal seeding, hematogeneous metastasis including the liver, lung, or bone, and rare unusual metastasis. Conclusion: Follow up CT plays an important role in identification of tumor recurrence after endoscopic treatment of EGC. Because early identification may allow patients to respond better to chemotherapy or radiation therapy, familiarity with the CT findings of tumor recurrence after endoscopic treatment of EGC is important.

Intragastric hematoma mimicking a gastric neoplasm: clinical and imaging findings D. Emlik, D. Aydogdu Kiresi, S. Gumus, K. Odev; Konya/TR purpose: To present the radiological findings of a large gastric hematoma secondary to duodenal peptic ulcer disease. material and methods: 68 years-old male with severely having epigastric pain accompanied by melena and hypotension found to have a focal mass in the epigastric region. There was no vomiting or hematemesis. The patient refused the barium study because of his clinical and hematological deterioration. Ultrasonography, spiral CT and T1 and T2 MRI were performed. results: Ultrasonography showed a large heterogeneous hypoechoic mass with having multiple acustic posterior shadowing areas within the stomach. Spiral CT scan revealed a marked dilatation of the stomach and a huge, moveable hypodense mass inside the stomach and duodenum. Precontrast and postcontrast CT scan revealed that intragastric mass had the same density in both studies. MRI confirmed the CT findings. At surgery, there was a duodenal ulcer and huge hematoma within the lumen of the stomach and duodenum that caused complete obstruction of the passage. During the operation, active bleeding was not controlled and unfortunately the patient died in a few hours. Conclusion: Although endoscopy and barium studies are still very important for the diagnosis of upper GI bleeding, CT scan may also be a useful method in determining of complications that occur due to ulcer bleeding. To provide a comprehensive overview of the videofluoroscopic swallowing study in modern radiological practice, focussing on the importance of clinicoradiological correlation in identifying abnormalities and their impact on patients' lives. Background: Swallowing abnormalities are a diverse group of disorders affecting patients of every age. The videofluoroscopic swallowing study (VFSS) is a technique commonly used to investigate this problem. It requires an excellent understanding of the anatomy, physiology and pathology of swallowing. Most importantly, VFSS is a dynamic study requiring real-time correlation of clinical and radiological findings if it is to be used to full advantage. Imaging findings or procedure details: We describe the comprehensive VFSS service provided in our centre. We outline the technique itself, highlighting tips for best practice and potential pitfalls. We then review the range of disorders encountered, stressing the importance of clinicoradiological correlation by presenting video clips of patients with various disorders performing the study alongside the imaging findings themselves. Conclusion: VFSS is a dynamic technique demanding excellent clinical and radiological skills. We review the art and science of this important aspect of modern radiological practice.

monitoring therapeutic response of liver metastases from colorectal cancer treated with percutaneous radiofrequency ablation by diffusion-weighted mrI E. Szurowska, J.M. Pieńkowska, D. Zadrozny, E. Iżycka-Świeszewska, W. Adamonis, M. Studniarek; Gdansk/PL purpose: The purpose of our study was to evaluate the usefulness of quantitative diffusion-weighted MRI in monitoring therapeutic response of liver metastases from colorectal cancer treated with percutaneous radiofrequency ablation (RFA). material and methods: 40 patients (15 women and 25 men) with 72 hepatic metastases from colorectal cancer were prospectively evaluated with diffusionweighted imaging (DWI) one day before and 6 weeks after RFA using 1.5 T MR system. Apparent diffusion coefficients (ADCs) were measured in all lesions before and after treatment for different b factors (b= 0-15; 0-30; 0-300; 0-500; 0-2000 s/mm 2 ) and the relative posttreatment change in the ADC value for each tumor was calculated. All lesions were divided into two groups based on their treatment response using multislices CT scans performed 6-and 24-weeks after therapy: complete response (group A) was defined as avascular liver lesion in CT scans and incomplete response (group B) when residual tumor was observed in CT images. Changes in ADC value were compared between two groups. results: In 54 metastatic foci, complete responses for RFA therapy were observed (group A) and in the rest of lesions (18 metastases) active neoplastis processes were noted. Change in the ADC value and in relative post-treatment ADC value was statistically greater in group A. The mean post-treatment ADCs and relative post-treatment ADCs of completely responding metastases increased significantly 6 weeks after RFA compared to mean pretreatment and relative pretreatment ADCs (Wilcoxon-test, p=0.006 and 0.001).

The ADC value on DWI is a promising tool for monitoring the therapeutic response of liver metastases treated with percutaneous RFA. Background: Combined hepatocellular and cholangiocarcinoma (HCC-CC) is a rare tumor showing histological evidence of both hepatocellular and biliary epithelial differentiation. Because of its rarity, there have been few reports about the imaging findings of this tumor. Imaging findings or procedure details: We retrospectively reviewed MR findings of pathologically confirmed combined HCC-CC in 11 patients (all men; mean age, 50.9 years). The tumors were divided into three groups by gross pathologic examination: HCC type (n=2), CC type (n=8), and collision type (n=1). The images and pathologic findings were retrospectively compared. All patients showed high signal on T2 weighted images. Three tumors revealed focal high signal intensity on T1 weighted image due to necrosis. The CC types demonstrated peripheral rim-like enhancement (n=8) and irregular margin (n=7) with cirrhotic feature (n=8). The HCC types were well enhanced in the arterial phase and low signal intensity in the delayed phase. Lymph node enlargement and bile duct invasion were observed in two and one patients, respectively. (n=7), choledocholithiais (n=4), pancreatitis (n=2), diverticulitis (n=1), cholecystitis (n=1), hepatitis (n=1), inflammatory bowel disease (n=1), APN (n=1), phlebitis (n=1), postoperative state (n=1)), 13 malignancy (gastrointestinal (n=9), hepatobiliary (n=2), and gynecological (n=2)), and 8 other diseases. HCE pattern of focal or diffuse was not significantly different between inflammation and malignancy (p=0.246). Conclusion: HCE is not a unique finding in FHCS, and it could be presented in broad disease spectra of inflammation, malignancy, and the other diseases in the abdomen and pelvis. HCE may be one of the important findings that represent any kinds of inflammation or malignancy in the abdomen and pelvis.

morphologic changes of the liver: how to recognize and analyze at Ct and mrI O. Bruno 1 , G. Brancatelli 2 , A. Galluzzo 2 , M. Giraud 1 , M.P. Vullierme 1 , V. Vilgrain 1 ; 1 Clichy/FR, 2 Palermo/IT Learning objectives: To review the CT and MRI findings of liver morphology changes occurring in different conditions. Background: Knowledge of anatomic landmarks is crucial to recognize morphologic changes of the liver. Imaging findings or procedure details: Morphologic changes of the liver may be lobar or segmental and are mostly related to biliary strictures or vascular obstruction. We will review the most helpful hepatic anatomic landmarks in order to recognize liver morphology changes at imaging. We will review the morphologic changes occurring in liver cirrhosis and in those diffuse liver diseases that could be mistaken for cirrhosis, such as chronic Budd-Chiari syndrome, congenital hepatic fibrosis, pseudocirrhosis secondary to metastatic breast adenocarcinoma, and atrophy-hypertrophy complex secondary to cavernomatous transformation of the portal vein among others. 

The goals of this exhibit are to increase the radiologists' ability to: differentiate cirrhosis from diffuse liver disease mimicking cirrhosis; generate a differential diagnosis among those conditions causing liver morphology changes; and understand what type of vascular and biliary changes are more often associated with focal and diffuse morphologic changes of the liver.

diffusion-weighted mrI in the evaluation of liver hydatid cysts S. Bayramoglu, O. Kilickesmez, F. Palabiyik, E. Ozbalci, A. Kayhan, T. Cimilli; Istanbul/TR purpose: The purpose of our study was to evaluate the signal intensities of hydatid cysts on diffusion-weighted MRI (DWI-MRI) and the value of DWI in the differential diagnosis of simple and hydatid cysts of the liver. material and methods: Thirty-four simple and 73 hydatid cysts were included in this study. All hydatid cysts were examined by sonography and classified according to the World Health Organization. The diagnosis of hydatid cysts was confirmed by biopsy or positive serology. DWI were acquired using the following b values: 0,500 and 1000 s/mm². ADC maps were reconstructed from these images. On DW trace images, signal intensity of cysts were visually compared with the signal intensity of the liver using a 5 point scale. The signal intensity of the cysts, cyst to liver signal intensity ratios, ADC of the cysts and cyst walls, cyst to liver and wall to liver ADC ratios were compared between the groups quantitatively. results: All ADC values and ratios were shown to gradually decrease parallel to the maturation of cysts. In visual scoring with a b factor of 1000, the signal intensities were different between simple cysts and complete liquid type hydatid cysts (p=0.032). Background: Contrarily to the most frequently seen MRI pattern, liver nodules may show total or partial hypointensity on T2-w images. T2-w hypointensity can be absolute or relative depending on the native signal intensity of the normal parenchyma and/or sequence used. Causes for absolute hypointensity include haemorrhage, iron (native or exogenous from contrast agents), calcium, copper or melanin deposition, and also abundant fibrous or smooth muscle stroma. Relative hypointensity is seen in lesions with a fatty component. Imaging findings or procedure details: Despite rare, low signal intensity regarding the surrounding liver on T2-w images may be found in a wide spectrum of lesions. Examples shown include focal nodular hyperplasia, hepatocellular adenoma (HCA), hepatocellular carcinoma (HCC), metastases (including metastatic melanoma), leiomyoma, nodular regenerative hyperplasia/regenerative nodules, dysplastic nodules, siderotic nodules, nodules in Wilson's disease, granulomas and inactive hydatid cysts. Lipoma, angiomyolipoma, HCA and HCC may also display T2-w hypointensity depending on the technique used to achieve fat-suppression. Conclusion: T2-w hypointensity, although a less common presentation of focal liver lesions, has a variety of causes. Their knowledge is helpful to derive the correct diagnosis, integrated in the clinical context. In some cases, however, radiological-pathological correlation is necessary to understand the full-blown picture for the hypointense appearance.

Imaging Imaging findings or procedure details: We searched our archive for portal vein (PV) pathology. A wide array of several acquired and congenital disorders of the PV and its branches are presented in this educational exhibit with CT and MRI findings. Among these are acute and chronic thrombosis of the PV and cavernomatous transformation, agenesis of the PV, gas in the PV due to mesenteric ischemia, bland and tumor thrombus of the PV in the setting of HCC, invasion of the PV secondary to extrahepatic malignancies and a very rare case of agenesis of the PV in a pediatric patient with biliary agenesis. Also, imaging findings of patent ductus venosus and anomalous pulmonary venous return to PV are included. Conclusion: Prompt and precise diagnosis of PV pathology may dramatically affect the treatment work-up of the patients. Therefore, we think that the in-depth knowledge of these processes is the sine qua non of a successful practice in both abdominal and general radiology. Magnetic resonance imaging (MRI) has been used in the surveillance of these patients due to exquisite soft tissue contrast capability without ionizing radiation. As more patients undergo liver tumor ablation procedures, it will become increasingly important that radiologists be able to recognize typical postablation MRI findings. In our department, more than 200 liver tumors (130 cryoablations, 99 RF ablations, and 16 alcohol injections) have been ablated, a majority of which has been followed up with MR imaging. In this presentation, we reviewed post ablation MR imaging features of liver tumors with illustrated examples. Imaging findings or procedure details: After successful ablation, liver tumors typically show no enhancement. Although a thin peripheral rim of enhancement may be seen in completely ablated tumors and may last several months, areas of nodular enhancement at the site or vicinity of an ablation zone is suggestive of residual/recurrence tumor. Conclusion: MRI is a useful modality in surveillance of liver tumor following percutaneous ablation. Subtraction is helpful to demonstrate unenhanced ablation zone and detect abnormal enhancement.

the value of the multi-detector-row Ct angiography in the study of hepatic arterial variants L. Saba, R. Sanfilippo, R. Montisci, G. Mallarini; Cagliari/IT Learning objectives: 1) To review hepatic arterial vascular anatomy. 2) To learn, according to Michels' classification, the types of hepatic arteries anomalies and its frequencies.

3) To analyze the MDCT technical parameters to be used: volume and concentration of contrast material, mAs and kVs, and the correct delay time. 4) To understand the indications for performing hepatic CT angiography underlining radiation exposure, cost and diagnostic efficacy. 5) To show which postprocessing techniques can be used including multi-planar reconstruction (MPR), maximum intensity projection (MIP) and volume rendering (VR). Background: The study of hepatic arteries results is extremely important in several pathological conditions, in particular in pre-surgical planning for patients undergoing hepatic surgery or in patients undergoing selective chemotherapic infusion. Multi-detector-row CT angiography (MDCTA) can produce excellent image quality and detail of hepatic arteries by correctly identifying anatomical variants. Imaging findings or procedure details: In this educational exhibition, we describe MDCTA technical parameters for the study of hepatic arteries. We present also examples both of normal hepatic arteries and hepatic variants by using axial images and reconstruction methods (MIP, MPR and VR). We present and discuss some relevant cases in order to underline benefits and pitfalls of MDCTA. Accurate delineation of the tumor extent poses a great challenge to modern imaging methods and MDCT as a single modality has the potential to comprehensively evaluate each patient for all the criteria of unresectability. It also has the potential of obviating the need for preoperative angiography in most cases. Magnetic resonance imaging (MRI) along with magnetic resonance cholangiopancreatography (MRCP) is ideally suited to evaluate the bile ducts and also identifies intrahepatic mass lesions. Imaging findings or procedure details: We will review HCC and intrahepatic colangiocarcioma separately. Current staging system will be presented and illustrated in a multimodality approach, focusing of the criteria of resectability. MDCT 3D reconstructions and corresponding evaluation of the potential extent of resection required in operable candidates is discussed.

The role of imaging, particularly volumetric MDCT, is crucial in preoperative staging and determining resectability of primary hepatic cancer. Adequate preoperative staging affects the therapeutic management and outcome of patients.

Hepatic enhancement in multiphasic mdCt: analysis of the different concentration and same iodine total dose with the same iodine flux administration in the same chronic liver disease patients N. Takeyama 1 , Y. Ohgiya 2 , T. Hayashi 1 , Y. Kinebuchi 1 , H. Shinjyo 3 , T. Kitahara 1 , T. Gokan 2 ; 1 Yokohama/JP, 2 Tokyo/JP, 3 Fukushima/JP purpose: To evaluate the hepatic enhancement and image quality in patients who underwent contrast-enhanced dynamic imaging on MDCT twice using 80 ml of 370 mg I/ml contrast material (CM) and 100 ml of 300 mg I/ml CM with the same iodine flux administration during follow-up periods. material and methods: Twenty-four patients weighing 50-65 kg with cirrhosis or chronic hepatitis were the subjects of the study. MDCT examinations using 100 ml of 300 mg I/ml at a flow rate of 4.0 ml/sec (1.2 g/sec) in protocol A, and 80 ml of 370 mg I/ml at a flow rate of 3.2 ml/sec (1.184 g/sec) in protocol B were performed in the same patients. After unenhanced scans, multiphasic scanning at 25, 40, 70, 180 sec was started after CM injection. Bolus tracking and saline flushing were not used. The CT values of hepatic parenchyma, abdominal aorta, and portal vein were measured. Their mean enhancement value was quantitatively analyzed. Hepatic enhancement and vascular enhancement were assessed qualitatively using a 4-point scale. results: There were no significant differences between the two groups in the mean enhancement of hepatic parenchyma, abdominal aorta, and portal vein. Quantitative assessment for the segmental branch of hepatic artery, intrahepatic portal vein, and hepatic parenchyma show no significant difference between two groups. Conclusion: We conclude that MDCT using 80 ml of 370 mg I/ml CM can decrease flow rate, while maintaining the same qualitative and quantitative performance.

segmental high intensity on t1-weighted hepatic mr images M. Hashimoto, J. Heianna, K. Yasuda, J. Watarai; Akita/JP purpose: We evaluated the diagnostic importance of segmental high-intensity (SHI) areas not corresponding to mass lesions on T1-weighted MR images. material and methods: We conducted a retrospective investigation of hepatic MR images obtained from patients during a 4-year period at our institution. There were 16 patients (2.5%) with SHI areas not corresponding to a mass lesion. We compared MR images with plain computed tomographic (CT) scans (n=16), angiograms (n=12), and histologic findings (n=10). results: The segments with intrahepatic bile duct dilatation showed hyperintensity on T1-weighted images. In six of 16 patients, the biliary duct was more dilated in the area of hyperintensity than in areas without hyperintensity. The SHI areas appeared as areas of low attenuation (n=13), high attenuation (n=1), or isoattenuation (n=2) on plain CT sans. Histologically, these areas showed ductular proliferation and deposition of bile pigment within the hepatocytes. Conclusion: Segmental areas of increased hyperintensity on T1-weighted images were probably due to intrahepatic cholestasis.

Incidence . To review the current indications for performing a study of hepatic veins by using multi-detector-row CT, underlining radiation exposure and diagnostic efficacy. Background: A correct assessment of the hepatic vasculature and, in particular, precise delineation of hepatic venous architecture, is important in several conditions: in particular pre-surgical planning for patients undergoing hepatic surgery (tumor resection, transplants). Multi-Detector-Row CT Angiography (MDCTA), by using fast patient scanning and thin collimation, can obtain nearisotropic voxels, producing excellent image quality and detail. Imaging findings or procedure details: In this work, we will present several imaging findings examples of normal anatomy of hepatic veins and their variants by using source axial images and post-processed methods. We present also relevant case studies. Conclusion: MDCTA allows to obtain optimal image quality in the study of hepatic veins in order to correctly plan a liver resection. To prospectively describe parameters of CT perfusion for evaluation of tumor vascularity in different aspects of liver metastases from endocrine tumor. material and methods: Prospective analysis of CT perfusion was performed in 16 patients with 30 liver metastases which were classified in 3 groups: hyperdense, hypodense on arterial phase and necrotic. Sequential acquisition of the liver was performed before and during 2 min after intravenous injection at 4cc/sec, 0.5 mg/kg of contrast medium. Data were analyzed using deconvolution analysis to calculate blood flow (BF), blood volume (BV), mean transit time (MTT), Arterial hepatic index (AHI) and bi-compartmental analysis to obtain vascular surface permeability (SP). Post treatment was performed by a radiologist and ROI were plotted on metastases, normal liver, aorta and portal vein. results: In case of necrotic metastases, none of the CT perfusion parameters was changed. Compared to normal liver, significant difference was found for all CT perfusion parameters in case of hyperdense metastases and only for AHI and MTT in case of hypodense metastases. No significant difference was found for MTT and AHI between hypo and hyperdense metastases; otherwise, we describe significant decrease of SP in hyperdense lesion and significant decrease of BV and BF in hypodense lesions. Conclusion: Results suggest that CT perfusion allows differentiating tumor vascularity in case of liver metastases from endocrine tumor.

Usefulness of multiplanar reconstruction with multislice Ct to assess HCC response after transcatheter arterial chemoembolization T.V. Bartolotta . material and methods: Fifty-seven patients (mean age: 68.3 years) with unresectable HCC (mean size: 3.4 cm) treated with TACE underwent multiphase MSCT one month after treatment. To evaluate the necrosis rate on MSCT, the following formula: (unhenancing area)+(iodized oil retaining areas)/(total tumoral area) x 100 was calculated on three planes (axial, coronal, and sagittal), choosing the slice in which the tumor showed the largest diameter and the mean value was obtained. As complete necrosis was considered the absence of enhancing portion within or at the margin of the nodule during the arterial phase, with homogeneus deposition of Lipiodol within the lesion whereas as residual tumoral an irregular peripheral-enhancing focus in the arterial phase with irregular or incomplete Lipiodol retention. Responders were patients with a necrosis rate >50%, whereas non-responders were patients with a necrosis rate <50%. 

esophagogastric veins: can their calibration changes be used as a diagnostic sign for portal hypertensive gastropathy?

A. Erden, R. İdilman, I. Erden, A. Özden; Ankara/TR purpose: We analyze whether esophagogastric venous caliber changes can be accepted as an indirect diagnostic evidence for the presence of portal hypertensive gastropathy (PHG). material and methods: The images of 57 patients with portal hypertension in whom MR portography has been performed were evaluated retrospectively. The diameters of the left gastric, esophagial mural and paraesophageal veins as well as azygos veins were measured. The mean diameters of the above-mentioned veins in patients with and without PHG were compared with Mann-Whitney U test. In addition, the diametral relationship between the left gastric and azygos veins (largeness or smallness of the left gastric vein compared to the azygos vein)

were assessed with Fisher's Exact test with respect to the formation of PHG. results: PHG was detected in 15 (26.3%) patients at endoscopy. In patients with PHG, the mean diameters of the left gastric, esophagial mural, paraesophageal, and azygos veins were not statistically different from those in patients without PHG (p>0.05). There was no significant difference in diametral relationship between the left gastric and azygos veins in patients with and without PHG. Conclusion: Interpretation about the presence of the PHG cannot be made by considering the esophagogastric venous calibrations. Largeness or smallness of the left gastric vein with respect to the azygos vein is not a factor that effects the formation of PHG.

arterial analysis of the medial segment of the left hepatic lobe using mdCt L. Saba, G. Caddeo, G. Mallarini; Cagliari/IT purpose: Evaluating the arterial map of the medial segment of the left hepatic lobe (segment IV) is extremely important in pre-hepatic surgical planning. The purpose of this study was to assess multi-detector-row CT angiography (MDCTA) potentiality in detecting segment IV arteries and to compare the diagnostic efficacy of Maximum Intensity Projection (MIP) post-processing method and source axial images. material and methods: Sixty-seven patients (43 male, 24 female, mean age 64 years, age range 39-78 years) were retrospectively analyzed. Each exam was performed with a multi-detector-row CT scanner using a 110-140 ml of non-ionic B 82 DOI: 10.1007/s10406-008-0008-8 (370 mg\ml) contrast material with a flow rate of 3-5 ml\sec. Two observers evaluated independently axial images and MIP images. results: By analyzing axial images, reader 1 detected 69 arteries in 60 patients (89.5% sensitivity) and reader 2 detected 69 arteries in 62 patients (92.5% sensitivity) with a kappa value of 0.782 (good agreement). By analyzing MIP images, reader 1 detected 75 arteries in 64 patients (95.5% sensitivity) and reader 2 detected 75 arteries in 65 patients (97% sensitivity) with a kappa value of 0.813 (very good agreement).

The results of this study suggest that MDCTA is an effective method to study segment IV arteries. The use of MIP produces excellent results with an optimal inter-observer agreement. Review key imaging findings helpful to the diagnosis. Comment on differential diagnosis and potential pitfalls. Background: Lymphoma is a type of cancer that originates in lymphocytes or, more rarely, of histiocytes. Infiltration of the liver at time of presentation is frequent. CT has many roles in the evaluation of Hodgkin and non-Hodgkin lymphoma. It is used to define the full extent of the disease, allow accurate staging, assist in treatment planning, and monitor patient progress and possible relapse. Radiology is important in diagnosing and following-up this form of cancer. Imaging findings or procedure details: Diffusely distributed, uniformly small nodules, larger masses, or a combination of the two, may be identified. Hepatomegaly is almost invariably present. Conclusion: CT is the study of choice for the detection and staging of Hodgkin and non-Hodgkin lymphoma. CT enables accurate measurement of both tumor extent and volume and provides information that can be used to plan an appropriate therapeutic regimen as well as follow the patient response to therapy.

Withdrawn by authors

Comparing volumetry to reCIst in multi-slice Ct followup of untreated liver metastases S.M. Berggruen, A. Korutz, R. Salem, V. Yaghmai; Chicago, IL/US purpose: The purpose of our study was to evaluate volumetry versus RECIST measurements of hepatic metastases for the purpose of estimating change in tumor bulk. material and methods: Thirty-nine non treated solid hepatic metastases (27 left and 12 right lobe lesions) on baseline or follow up contrast-enhanced multislice CT in twelve patients undergoing selective transcatheter arterial radioembolization were evaluated. The average time interval between CT exams was 6.2 weeks (range 3-18 weeks). Two radiologists evaluated the metastases by using automated software (Siemens Medical Solutions, Forchheim, GER) to obtain RECIST, volume and density measurements for each lesion. Paired T test was used to evaluate mean percentage change of volume, RECIST and density measurements. P<0.05 was considered significant. results: The mean RECIST measurement increased from 28.7 to 30.8 mm (11.03%, P<0.0018) while the mean volume for the same lesions increased from 13.5 to 17.0 mL (55.0%, P<0.014). The mean HU change was minus 4.51. Conclusion: Our results suggest that RECIST criteria underestimate change in tumor bulk. Automated volumetry of solid liver masses may be a more accurate method of measuring tumors, allowing for better approximation of tumor progression.

a simple method for estimation of liver volume using multidetector Ct and mr T. Frauenfelder, M.A. Müller Zurich/CH purpose: To prospectively assess whether an approximative calculation of the liver volume is possible with a simple formula with the usage of three diameters. material and methods: In 50 MR and 50 CT examinations of 100 patients with no free fluid, no liver lesion >1 cm in diameter and no respiratory or motion artifacts, two readers measured the largest ventrodorsal (a) and lateral (b) diameter in the axial plane and the largest craniocaudal (c) diameter in the coronal plane. The total liver volume was approximated using the formula a x b x c x 0.3. As reference standard for comparison, the total liver volume was determined by volumetry by a third reader. results: There was no significant disagreement between readers 1 and 2 regarding the approximated liver volumes (p=0.87). The correlation between the liver volume estimation of readers 1 and 2 and the volumetric data was significant for CT and MR data (r=0.9, p<0.0001). In 80% of the formula-based estimations of the liver volume, the error of the approximated volume was <10%. The maximal error that occurred was 22%. Conclusion: An approximative calculation of the liver volume is possible with the formula a x b x c x 0.3. The standard error with such a calculation is in most cases <10% and about 160-170 ml.

mr and mdCt based liver volumetry: is there a need for a conversion factor? C. Karlo, C.S. Reiner, S. Breitenstein, D. Weishaupt, B.

Marincek, T. Frauenfelder; Zurich/CH purpose: To correlate the virtually measured volume of resected liver specimen based on MDCT-or MR-imaging to the intraoperatively measured weight and volume with and without the use of a conversion factor. material and methods: 20 patients underwent partial liver surgery and were examined by 64s-MDCT (n=10) or 1.5T-MRI (n=10) before and by 1.5T-MRI (n=20) 8 days after surgery. The resected volume was measured on the preoperative scan by two readers with dedicated software using the postoperative MR images as visual aid. All volumes were multiplied by conversion factors known from literature. The converted virtually measured volumes were compared to the intraoperatively measured weight and volume. Wilcoxon signed-rank test, Pearson correlation coefficient and Bland-Altman plot were used for statistical analyses. results: There was a strong positive correlation between the virtually measured volumes and the intraoperative measured volumes. Using no conversion factor, significant differences were seen between the volumetry and the intraoperative assessed weight and volume of the liver specimen. With correction factors of 0.8 and 0.75, no significant differences were found (Wilcoxon signed-rank test). A Bland-Altman plot showed a slightly better result using a conversion factor of 0.8 for CT-group and 0.75 for the MR-group. Conclusion: The use of a conversion factor (0.8 for CT and 0.75 for MR) is highly recommended if absolute weights and volumes of liver segments are demanded. included in the study. These patients were subdivided into a liver cirrhosis group (LCG) and a non-liver cirrhosis group (non-LCG). We measured the RNHFI (mean standard deviation of hepatic signal intensity (SD), noise-corrected coefficient of variation (CV)) of three ROIs in the liver parenchyma on SPIO MRI. The LNHFI (AST-platelet ratio index (APRI)) of all patients was also calculated. We compared the RNHFI and APRI of the LCG with those of the non-LCG using the Student's t-test. A bivariate correlation was performed to investigate the relationship between the RNHFI and APRI in the LCG. results: For the LCG, the mean values of SD and CV on SPIO-enhanced MRI were 10.3±3.7 and 0.19±0.08, respectively. For the non-LCG, the mean values of SD and CV were 6.5±1.6 and 0.08±0.05, respectively. The mean APRI of the LCG and the non-LCG were 2.04±1.7 and 0.32±0.32, respectively. The SD, CV and APRI were significantly different between the LCG and non-LCG (p<0.05). In all patients, there were significant correlations between CV and APRI (r=0.438, p<0.001), and between SD and APRI (r=0.633, p<0.001).

The RNHFI and APRI were significantly different between the LCG and non-LCG. The RNHFI was significantly correlated with APRI. The aim of this exhibit is to review the imaging and histological findings of the pathological changes that can occur in liver during pregnancy. Three categories are considered: 1) Liver dysfunction specific to pregnancy, 2) Pre-existing disorders that may be aggravated by pregnancy and 3) Liver disease coincident with pregnancy. Background: The liver is subject to changes in pregnancy, some physiological and others pathological. In some patients, this is life threatening and requires urgent management. Knowledge of these and of their imaging appearances is essential for the radiologist to ensure appropriate treatment. Imaging findings or procedure details: 1) Physiological changes in the liver in pregnancy. 2) Imaging features with histological correlation of liver diseases specific to pregnancy: -Acute fatty liver of pregnancy -Intrahepatic cholestasis -Hypertension-associated liver disease -pre-eclampsia-hepatic infarction and rupture-HELLP syndrome. 3) Pregnancy and pre-existing liver disease: -Liver tumours -Portal hypertension -Congenital hyperbilirubinemia. 4) Liver disease coincident with pregnancy: -Biliary disease -Budd-Chiari syndrome. Conclusion: This review has shown the physiological and pathological changes that may occur in the liver during pregnancy with the spectrum of hepatic diseases and their characteristic imaging findings.

non-invasive assessment of hepatic fibrosis with mr elastography and spectroscopy: initial results E.M. Godfrey, I. Joubert, A. Priest, N. Griffin, G.J. Alexander, A.E. Gimson, M. Allison, S. Davies, A. Shaw, D.J. Lomas; Cambridge/UK purpose: Early and moderate stages of hepatic fibrosis are difficult to diagnose accurately using most imaging techniques making invasive liver biopsy necessary and serial studies difficult to undertake. Several MR techniques have recently been shown to improve on standard imaging. This work describes our initial experience with: Liver stiffness measurement using MR elastography (MRE), 31Phosphorus hepatic spectroscopy and T2w morphological imaging. material and methods: 10 consecutive patients with clinically suspected hepatic fibrosis referred for liver biopsy were recruited. Each patient underwent MR examination including: Multishot T2w RARE, MRE and 31P spectroscopy. The patients underwent a liver biopsy the same day as the MR examination. Each sequence was independently evaluated for: liver stiffness (KPa), PME/PDE ratio and morphological evidence of fibrosis. The liver biopsy was graded independently by a pathologist using the Ishak Fibrosis Score. results: A broad range (1-6) of Ishak fibrosis scores were found at histology. These correlated well (0.86 Pearson rank) with MRE stiffness values which ranged from 2.7 to 12.7 KPa. The correlation was poor (-0.15) with PME/PDE ratio which ranged from 17.9 to 46.2%. All except one examination was graded as normal morphologically on T2w imaging.

Although involving a small group of patients, the initial results suggest that MRE measurements of liver stiffness correlate well with histological fibrosis score in suspected liver fibrosis and appear to perform better than either morphological imaging or 31P spectroscopy.

apparent diffusion coefficient measurements with diffusion-weighted mrI for evaluation of hepatic cirrhosis E. Szurowska, J.M. Pienkowska, E. Iżycka-Świeszewska, R. Rzepko, D. Zadrozny, W. Adamonis, M. Studniarek; Gdansk/PL purpose: The purpose of this study was the evaluation of the apparent diffusion coefficients' value (ADCs) of diffusion-weighted MRI for the assessment of liver cirrhosis. material and methods: A total of 75 patients were prospectively evaluated with diffusion-weighted MRI using 1.5 T system. T1 and T2-weighted SE, FSE sequences and echo-planar diffusion-weighted MR study with different b factor (b= 0-15; 0-30; 0-300; 0-500; 0-2000 s/mm 2 ) were performed. Region of interests (ROIs) were set on ADC map in each hepatic segment and mean ADC for the liver of each patient was calculated. The patients were divided into two groups: group A -33 patients with clinical signs of cirrhosis (Child-Pugh stage A) confirmed by liver biopsy and group B -42 patients with normal liver function. The mean ADC for cirrhotic (group A) and non-cirrhotic liver for different b factor were compared. results: The ADCs value was lower in group A than in group B, but statistical differences were observed for low b factor: b= 0-15 and 0-30 s/mm 2 (retrospectively p=0.001 and p=0.002). Conclusion: ADCs measurements for low b factor are potentially useful for the evaluation of cirrhotic liver. material and methods: 1H-MRS was performed in twelve subjects on a 3.0 T Philips scanner. Each subject underwent four 1H-MRS scans: two in fasting condition on the same day, and two one week later, before and after a high fat breakfast. From the spectra, a ratio representing hepatic fat content (mg fat per gram liver tissue) was calculated and used to compare the 1H-MRS scans to assess reproducibility (Wilcoxon signed rank test and intra class correlation coefficient). results: Mean hepatic fat content in scan one and two was 37.1 and 37.0 mg/g, for scan three and four 40.1 and 42.4 mg/g. We found no significant difference in hepatic fat content between scan 1 and 2 (p=0.62), scan 1 and 3 (p=0.20) and scan 3 and 4 (p=0.11). The intra class correlation coefficient between all four 1H-MRS scans was 0.98 (p<0.001). 

Withdrawn by authors P-180 size variation in focal nodular hyperplasia assessed by mrI C. Ramírez Fuentes, P. Bartumeus, L. Marti-Bonmati, D. Frota Barroso, A. del Val Montañana; Valencia/ES purpose: To evaluate the variations in size in a series of focal nodular hyperplasia (FNH) lesions as assessed by MRI. material and methods: The medical records of patients with a final diagnosis of FNH with at least two MRI examinations were reviewed. All the patients were examined with a dynamic contrast-enhanced MR T1W sequence. Finally, 17 patients were included with a total of 28 FNH lesions. Lesions size in its greater diameter was measured in millimeters, at each contrast-enhanced MR examination. The percentage of variation was calculated (difference in maximal diameter normalized to the initial size). A significant variation was considered when there was a size changed greater than 15%. results: The mean time interval between the two imaging examinations for the whole group was 925 days (±521). Six out of 28 lesions (21%) showed a significant variation at its largest diameter. Four of them decreased in size while two increased, changes being modified as much as 48%. The other 22 lesions remained stable during the follow-up period. Change in size could not be related to any predisposing factor. Conclusion: FNH can vary significantly in its diameter during follow-up examination. As many as 21% of these lesions either enlarge or decrease in size. No relationship could be found between size variation and predisposing factors.

Quantitative diffusion-weighted mrI of focal hepatic lesions using parallel imaging techniques O. Kilickesmez, S. Bayramoglu, E. Inci, S. Aksoy, G. Yirik, S. Aydin, E. Hocaoglu, S. Dogan, T. Cimilli; Istanbul/TR purpose: The purpose of this study was to investigate the value of diffusionweighted magnetic resonance imaging (DW-MRI) in the discrimination of mass lesions of the liver using parallel imaging technique. material and methods: A total of 77 patients (mean age, 59), and 65 healthy controls (mean age, 37.6) were enrolled in the study. SS SE EPI DW-MRI was performed with b factors of 0, 500 and 1000 s/mm². ADC values of the normal liver and the lesions were calculated. results: There was statistically significant difference among ADCs of four liver segments. The mean ADC value of the liver lesions was as follows: simple cysts (3.16±0.18x10-3 mm²/s), hydatid cysts (2.58±0.53x10-3 mm²/s), metastases (1.14±0.41x10-3mm²/s) and hepatocellular carcinomas (HCC) were (1.15±0.36x10-3mm²/s). The mean ADC values of all of the lesion groups were statistically significant when compared with mean ADC value of the normal liver (1.56±0.14 x10-3 mm²/s), (p<0.01). There was also statistically significant difference among the ADC values of hemangiomas and HCCs-metastases, simple and hydatid cysts. However there was no statistically significant difference between HCCs and metastases.

The present study showed that ADC measurement has a potential ability to differentiate focal hepatic lesions. We propose to add the DW sequence in the abdominal MR protocol for the detection and discrimination of hepatic lesions and particularly in the differentiation of benign and malignant ones.

the role of diffusion weighted mrI to the differantial diagnosis of hepatic masses I. Guvenc, M. Kocaoglu, I. Karademir, N. Bulakbasi, C. Tayfun; Ankara/TR purpose: The purpose of this study was to evaluate the diagnostic role of diffusion weighted MRI using apparent diffusion coefficient (ADC) values and in the characterization of hepatic mass lesions. material and methods: 96 patients who had 129 lesions were examined and underwent abdominal MRI at 1.5 T, including T1-, T2-weighted, and dynamic gadolinium-enhanced imaging. Axial diffusion weighted images was performed before contrasts administration with a single-shot spin-echo echo-planar imaging sequence using b-values of 50,400, and 800 seconds/mm 2 . ADC maps were obtained automatically by the device and all ADC values of the lesions were measured. Statistical analyses were performed using the T test and Mann-Whitney U test in a computer software (SPSS Inc., Chicago, Illinois, USA). The differences were considered significant when p values were less than 0.05. results: The lowest ADC values among the malignant masses belonged to metastases. Hepatocelluler carcinomas ADC values were slightly higher than metastases. All malignant liver lesions characterized by high signal intensity (SI) in b=800 images and low SI in ADC map images. The highest ADC value was for simple cysts. All benign lesions had high SI in ADC map images. The difference between the mean ADC values of benign and malignant lesions was statistically significant (p<0.01). Conclusion: Diffusion weighted images with ADC measurement can differentiate benign from malignant lesions.

multiple hyperechoic liver lesions: an early indicator of haemochromatosis? S.J. Amonkar 1 , L. Tandon 2 , C.K. Liew 1 , S. Sukumar 1 ; 1 Manchester/UK, 2 Blackpool/UK Learning objectives: To consider HC in the differential diagnosis of multiple HLL in the adult patient with deranged liver function tests (LFTS). Background: Haemochromatosis (HC) is characterised by a gradual increase in body iron, and can be hereditary or secondary. Both types cause abnormal iron deposition in multiple organs, most commonly the liver. If untreated, the subsequent cirrhosis significantly increases the risk of HCC. Current radiological evaluation is principally centred around MRI, and to a lesser degree, CT. Although often a first line investigation, limited literature exists relating to the role of US in the diagnosis of HC. B 86 DOI: 10.1007/s10406-008-0008-8 Imaging findings or procedure details: We consider 4 cases that initially presented with abnormal LFTS and were later proven to have HC. In these cases, the initial US showed multiple hyperechoic liver lesions (HLL) where the differential diagnosis included haemangiomas, focal fatty infiltration, metastases and hepatic adenomas. We will illustrate these findings with correlation to MRI and CT images where available. Histological correlation will also be illustrated with a review of the literature. Although these lesions had imaging characteristics of fat containing lesions, it is interesting that this particular pattern was noticed in the presence of underlying HC. Conclusion: Early diagnosis of HC could prevent the development of fatal complications, and although non-specific, it should be considered in the differential diagnosis of multiple HLL.

Gamut of focal fatty liver masses: value of cross-sectional imaging in diagnosis with emphasis on mrI N. Fasih, S. Thipphavong; Ottawa, ON/CA Learning objectives: To present a series of well documented cases of benign and malignant liver lesions that may typically or occasionally contain fat. Benign fat-containing liver lesions include: Focal nodular hepatic steatosis, Giant hepatic echinococcal cyst, Focal nodular hyperplasia (FNH), Hepatic angiomyolipoma, and Hepatic adenoma. Malignant fat-containing liver lesions include: Hepatocellular carcinoma (HCC) and metastatic liposarcoma. To demonstrate and discuss the role of multimodality imaging in the diagnosis of fat-containing liver lesions. Background: When fat is seen within a liver mass, a spectrum of lesions needs to be considered. Although some lesions are benign and uncomplicated, others may be malignant. Cross-sectional imaging including CT, MRI and even US can diagnose intra-lesional fat with high accuracy. Characterization of these lesions on imaging can allow for a specific diagnosis or can help narrow the differential diagnosis. By combining the radiological findings and patient characteristics, the nature of the lesion can often be determined. Often, this may obviate the need for biopsy. Imaging findings or procedure details: Clinical and imaging features of benign and malignant fat-containing lesions mentioned in the Learning objectives: will be discussed. Utilization of CT Hounsfield units for macroscopic fat determination, combined with additional imaging features and patient factors, to determine a diagnosis or generate a differential diagnosis. Emphasis on MRI fat-saturation and chemical shift sequences for the determination of macroscopic and intracellular lipid-containing lesions, respectively. Conclusion: A variety of fat containing lesions may be encountered within the hepatic parenchyma. Cross-sectional imaging, especially MRI, can make a specific diagnosis or narrow the differential diagnosis, thereby facilitating correct management.

Withdrawn by authors P-186 pure bile ductular carcinoma: imaging pathologic correlation in comparison with ordinal type of cholagiocellular carcinoma K. Kozaka, O. Matsui, S. Kobayashi, Y. Nakanuma, Y. Zen; Kanazawa/JP purpose: To assess CT findings of bile ductular carcinoma with correlation to pathologic findings in comparison with ordinary cholangiocarcinoma. material and methods: 21 surgically resected peripheral cholangiocaricnomas were divided into three types: adenocaricnomas resembling proliferating reactive bile ductules (bile ductular carcinoma, pure type), variably sized tubular, solid or micropapillary adenocarcinomas (ordinary type) and mixed type. Tumor growth patterns were classified pathologically as replacing growth pattern and compressive growth pattern. The tumor and peritumoral enhancement patterns of these three types were examined. results: All pure type showed replacing growth pattern. All pure type showed diffuse stain and 3 of 6 pure type showed peritumoral wedge shaped stain. None of 6 accompanied intrahepatic bile duct dilatation. 6 of 8 mixed type showed replacing growth and the remaining 2 showed compressive growth. 7 of 8 mixed type showed peripheral rimlike enhancement. 6 of 8 mixed type showed peritumoral wedge shaped stain and 3 accompanied intrahepatic bile duct dilatation. 4 of 7 ordinary type showed replacing growth and the remaining 3 showed compressive growth. 4 of 7 ordinary type showed diffuse stain and the remaining 3 showed peripheral rimlike stain. 6 of 7 showed peritumoral wedge shaped stain and 4 accompanied intrahepatic bile duct dilatation. Conclusion: The CT findings of pure type may be characterized by diffuse stained tumor without intrahepatic bile duct dilatation.

Imaging findings of hepatic tumors that can contain large amount of fat J.Y. Woo, I. Yang, S.Y. Chung; Seoul/KR Learning objectives: To illustrate characteristic appearance and discuss differentials of hepatic tumors that can contain a large amount of fat. To emphasize on early diagnosis of well-differentiated liposarcoma of the liver. Background: Hepatic tumors that can contain large amount of fat are lipoma ,angiomyolipoma,and well-differentiated liposarcoma. Hepatic lipomas are rarer than angiomyolipomas and can occur sporadically. Hepatic angiomyolipoma is a rare benign mesenchymal tumor. Well-differentiated liposarcoma is a rare malignant tumor. Because of their rarity and similar imaging findings, we often consider masses containing large amount of fat as benign lesions. So early diagnosis of well-differentiated liposarcoma is not easy. According to the clinical course, liposarcoma of the liver has a high rate of recurrence. Generally, the prognosis is poor without treatment. The well-differentiated type is considered to have low-grade malignancy. Other types are regarded as intermediate or highly malignant tumors. It is possible to differentiate the well-differentiated liposarcoma from an angiomyolipoma or lipoma on MDCT and MR imaging. Imaging findings or procedure details: An angiomyolipoma presents with central vessels within the lesion as a characteristic feature and lipoma appears as a pure fat-containing lesion on CT and MR. Well-differentiated liposarcomas show an almost fatty, lobulated mass with a few, random distributed vascular structures and small areas of nodular enhancement. Conclusion: Well-differentiated liposarcoma of the liver should be included in the differential diagnosis of hepatic masses containing large amount of fat when imaging findings show an almost fatty, lobulated mass with a few, random distributed vascular structures and small areas of nodular enhancement.

Contrast enhanced Us in the characterization of small liver lesions (≤1 cm), indeterminate on mdCt in neoplastic patients: a preliminary study E. Gatti, P. Cabassa, F. Pittiani, P. Narbone, E. Fogari, R. Maroldi; Brescia/IT purpose: To assess the efficacy of contrast enhanced US (CEUS) in the characterization of hepatic lesions (<1 cm), defined too small to be characterized at MDCT, in neoplastic patients. material and methods: 33 consecutive indeterminate lesions <1 cm in 16 neoplastic patients were depicted on 16 rows MDCT. All lesions underwent B mode baseline US and CEUS. CEUS was performed with the standard dose of 2,4 ml Sonovue using real time continuous scanning during arterial, portal and late phase with specific contrast setting (contrast coherent imaging: CCI) at low MI (0.1-0.2). The gold standard was clinical follow-up of at least 6 months with adequate imaging findings (MR, US, MDCT). results: Final diagnoses were: 13 cysts, 3 hemangiomas, 2 metastasis, 4 benign lesions, not characterized, but unmodified during follow up. 11 lesions were undetected both at baseline US and CEUS. Imaging follow-up shows no lesions within the liver in these patients. 9 lesions in 4 patients were cysts, detected with B-mode US without contrast administration. In 12 patients, CEUS correctly characterized 21/24 lesions (87.5%). Overall US (B-mode and CEUS) has correctly characterized 30/33 lesions (90.1%). Learning objectives: 1. Overall view of different modalities of imaging used to diagnose and characterize FLL. 2. Define radiographic appearances of these lesions on different imaging modalities. Background: Focal liver lesions (FLL) can be benign or malignant. Commonly seen benign lesions are cysts, haemangiomas, focal nodal hyperplasia, hepatic adenomas and biliary cyst adenomas. Malignant lesions can be primary or secondary. It is important to differentiate between the two to optimize treatment and to avoid unnecessary interventions. Various radiological imaging modalities are employed for the diagnosis and characterization of FLL. The enhancement pattern of a lesion constitutes the mainstay of its characterization with contrastenhanced CT or MRI. Imaging findings or procedure details: Based on our experience, we present a spectrum of appearances of FLL seen on USS, CT scan and MRI. CT images were obtained pre and post intravenous contrast. Liver specific contrast agents and gadolinium were used for MRI scan. The characteristic appearances of the mentioned lesions are described here in a pictorial review. Conclusion: Different modalities contribute to the diagnostic assessment and have their own advantages and disadvantages. USS is highly sensitive in the diagnosis, but less specific in characterizing these lesions. However, MRI with newer liver specific contrast agents is more sensitive and specific in the diagnosis of FLL compared to multislice spiral CT.

Focal nodular hyperplasia or hepatic adenoma? How mrI can help us using liver-specific contrast agents P. Paolantonio 1 , R. Ferrari 2 , P. Lucchesi 2 , F. Vecchietti 2 , M. Rengo 2 , A. Laghi 2 ; 1 Rome/IT, 2 Latina/IT Learning objectives: To illustrate pharmacodynamic and pharmacokinetic properties of Gd-BOPTA, Gd-EOB-DTPA and ferucarbutran. To show pathological features of FNH and HA with imaging correlation. To show typical and atypical features of FNH and hepatic adenoma at MRI using different classes of hepatospecific contrast agents. Background: Differential diagnosis between Focal Nodular Hyperplasia (FNH) and Hepatic Adenoma (HA) is crucial for patient management. An accurate and non-invasive differential diagnosis using MRI is possible based on both dynamic imaging and functional information of liver-specific contrast-agents. Imaging findings or procedure details: The identification and characterization of FNH and HA requires an accurate dynamic study of the liver for the assessment of lesion vascularity. Unfortunately, a definite differential diagnosis on the basis of morphology and lesion vascularity is not always possible. Functional information offered by liver specific contrast agent may help us in this diagnostic challenge. Conclusion: The use of liver specific contrast agents offers functional information on lesion cellularity that is extremely useful in differentiating FNH by HA. Information on lesion bile ducts offered by hepatobiliary agents represents an accurate marker of FNH nodule respect to HA.

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Inhomogeneity is frequently encountered in focal nodular hyperplasia on delayed with Gd-eoB R.H.C. Bisschops, M.S. van Leeuwen; Utrecht/NL purpose: Dynamic MRI with Gd-EOB can be used to characterize focal nodular hyperplasia (FNH). However, the optimal time window for delayed enhancement is not yet defined and atypical enhancement patterns are reported. We prospectively evaluated 10 probably FNHs with dynamic MRI using Gd-EOB, using multiple time delays. material and methods: T1w, T2w and THRIVE unenhanced, arterial (20 sec), portal (50 sec), equilibrium (3 min) and delayed phase (10, 20 and 30 min after injection of Gd-EOB) were obtained. Lesion signal intensity and homogeneity were graded for each sequence and time window. Presence of a central scar and time of biliary excretion was noted. results: Nine FNHs showed typical homogeneous enhancement during arterial, portal and equilibrium phases, seven with a scar and two without a scar. One atypical FHN was iso-intense on portal phase and slightly hypo-intense in the equilibrium phase with no central scar. On delayed imaging, two FNHs were isoand slightly hypointense. Five FNHs showed marked inhomogeneity, four only during delayed enhancement, one during all time windows. No significant difference was observed between 10, 20 or 30 minutes images. Biliary excretion was seen from 10 minutes onward in nine patients. Conclusion: Using Gd-EOB, inhomogeneity is frequently encountered in FNHs on delayed imaging. A delay of 10 minutes may be sufficient for the hepatobiliary phase.

Fat-containing lesions of the liver: a common diagnostic challenge C.K. Liew, T.C. Oh, F.M. Grieve, J.K. Bell, B. Rajashanker; Manchester/UK Learning objectives: To identify and describe a wide spectrum of fat-containing lesions in the liver and the imaging characteristics that distinguish them. To review current MRI techniques used in characterisation of these lesions. Background: A fat-containing lesion within the liver is frequently encountered in clinical practice. The causes are diverse and can range from benign lesions to malignant neoplasm. The benign entities include hepatic steatosis, hepatic adenoma, focal nodular hyperplasia, angiomyolipoma, lipoma, teratoma, adrenal rest tumour and Langerhans cell histiocytosis. Malignant lesions include HCC, liposarcoma and metastatic liver lesions. Imaging findings or procedure details: Both US and CT can be useful to demonstrate the presence of fat. However, MRI is the most sensitive modality in the characterisation of these liver lesions. Several MRI sequences including inand-opposed phase gradient echo T1W sequence, spin echo T2W sequence, dynamic post contrast images and the use of liver specific contrast agents help to differentiate these lesions and aid in achieving an accurate diagnosis. In this pictorial review, we illustrate the radiographic features of various entities of focal and diffuse fat-containing lesions of the liver, with focus on MRI. A detailed understanding of these lesions is essential for further appropriate management. Conclusion: This presentation will help the readers to provide clinicians with the diagnosis or relevant differential diagnoses when confronted with a fat containing lesion of the liver.

a pictorial review of patterns of vascular involvement by HCC D. Lewis, P. Peddu;, A. Quaglia, P.A. Kane, J. Karani; London/UK Learning objectives: To demonstrate the breadth of liver vascular abnormalities associated with HCC. Background: HCC is a common, potentially curable primary liver malignancy but the presence of macrovascular tumour invasion alters both clinical presentation and subsequent treatment. Recognition of the patterns of arterial and venous tumour infiltration in HCC is an essential radiological skill which forms the basis of diagnosis and management. Imaging findings or procedure details: Multimodality techniques are used to demonstrate intrahepatic tumour stage, arterial venous and caval tumour/ thrombus infiltration and arterio-venous shunting. This exhibit will present a pictorial essay of these vascular complications, including hepatocyte specific contrast enhanced MRI, MDCT and angiography. Conclusion: Staging and determination of management of HCC requires accurate radiological depiction of macrovascular tumour invasion. This presentation uses case example to demonstrate the breadth of radiological appearances in this regard.

the relationship between hepatic mrI for fat quantification and hepatic vein waveform in patients with nonalcoholic steatohepatitis S. Ulusan, T. Yakar, Z. Koc; Adana/TR purpose: To investigate the relationship between hepatic vein waveform (HVW) and hepatic fat fraction was evaluated in patients with nonalcoholic steatohepatitis (NASH) using spectral Doppler US recordings and phase contrast MRI. B 88 DOI: 10.1007/s10406-008-0008-8 material and methods: A total of 52 patients, ages 26 to 70 years old with NASH underwent hepatic MRI for fat quantification. The degree of hepatic steatosis was assessed by MRI through chemical shift imaging using a modification of Dixon method. The Doppler US examination of middle hepatic vein was performed in all patients. The Doppler US pattern was classified in to two groups according to Doppler signal characteristics: abnormal (monophasic and biphasic) and normal (triphasic). The degree of correlation between the Doppler signal characteristics and hepatic fat fractions was assessed using a linear regression test. results: In 23 patients (44%) with NASH, the Doppler US spectrum of the middle HVW was monophasic-biphasic. Triphasic HVWs (normal waveform) were found in 29 (56%) patients. The results of Doppler US were correlated with the hepatic fat fraction (p<0.0001). Conclusion: On duplex Doppler sonography, the abnormal (monophasic and biphasic) flow pattern in the middle hepatic vein is mainly caused by the level of hepatic fat fraction in patients with NASH.

the role of imaging techniques in acute bleeding liver: a rational approach J.C. Quintero, S. Mourelo, C. Roqué, J. Sampere, J.A. Jiménez, E. Barluenga; Badalona/ES Learning objectives: 1) Recognize the imaging radiology manifestation of hemoperitoneum originate in the liver and identify key CT features that may help direct management. 2) Establish the differential diagnosis of hemorrhagic hepatic conditions, traumatic and no traumatic. Background: Spontaneous hepatic bleeding is a rare condition. In the absence of trauma or anticoagulant therapy, hepatic hemorrhage may be due to underlying liver disease. The most common causes of no traumatic hepatic hemorrhage are HCC and hepatocellular adenoma. Such hemorrhage can also occur in patients with other liver tumors, and other conditions. Imaging findings or procedure details: We reviewed retrospectively 29 patients with acute bleeding liver diagnosed in our institution. We present a comprehensive algorithmic approach to diagnose in acute bleeding liver. 1) Traumatic conditions (11); 2) HCC (6); 3) Hepatocellular adenoma (2); 4) Other liver neoplasms: focal nodular hyperplasia (1), hepatic hemangioma (1), hepatic metastasis (3) hepatic hamartoma (1) and primary hepatic lymphoma (1); and 5) Other conditions associated with spontaneous hepatic haemorrhage: HELLP syndrome (2), amyloidosis, peliosis, connective tissue diseases, infectious diseases, and parasitic diseases (1). Conclusion: Hemoperitoneum may occur in various emergent conditions. In the trauma setting, evidence of intraperitoneal blood depicted at CT should lead the radiologist to conduct a careful search of images for the injured visceral organ. Imaging plays a significant role in the diagnosis and management of this potentially lethal entity.

Hepatic fascioliasis: imaging characteristics with a new finding Z. Koc, S. Ulusan, N. Tokmak; Adana/TR purpose: To present the imaging characteristics of four patients with hepatic fascioliasis (HF) showing a new finding. material and methods: Imaging and clinical findings of four patients diagnosed with HF were evaluated retrospectively. All patients were examined by abdominal US and MDCT, and two of them additionally evaluated by abdominal MRI, MRCP and ERCP. Diagnosis was confirmed by serological and parasitological tests in all patients. results: Presenting complaints were abdominal pain and fever in all patients. All patients also had eosinophilia and abnormal liver fuction tests. In all patients, US examinations showed irregular marginated hypoechoic areas, and MDCT examinations showed branching irregular linear and nodular nonenhancing hypodense areas in the liver. Apart from these findings, hyperdense materials identified in the dilated bile ducts in one patient were revealed as a new finding. MRI showed hypo (T1) and hyperintense (T2) areas of liver parenchyma in two patients, with peripheral enhancement in one of them. Filling defects and dilation of the intraextrahepatic bile ducts were identified by US and MRCP in two patients. In these two patients, fasciola flukes were removed by ERCP. Medical treatment (triclabendazole) was successful in all patients. Conclusion: HF is a rare disease that may have typical imaging findings in the liver and bile ducts. Imaging characteristics with clinical findings may have a diagnostic clue especially in endemic areas.

Frequency of asymptomatic intrahepatic spontaneous portosystemic venous shunts on abdominal mdCt S. Senturk, A.T. Ilica, A. Bilici; Diyarbakir/TR purpose: The portosystemic venous shunts within the hepatic parenchyma are considered to be rare and their cause is controversial. With recent advances in diagnostic imaging techniques, the number of reports of intrahepatic portosystemic venous shunts identified incidentally in asymptomatic patients is increasing. The purpose of this study is to determine the frequency of asymptomatic intrahepatic portosystemic venous shunts on MDCT of the liver. material and methods: We retrospectively reviewed 196 dynamic CT examinations of the liver, which were performed using a 64-detector unit between April 2006 and December 2007. The study included 196 patients, aged 22-77 years (mean 52 years). All patients were administrated 120 mL of intravenous contrast material at an injection rate of 4 mL/sec. The images acquired at arterial and portal venous phases were reviewed using multiplanar reconstructions and maximum-intensity-projection. The clinical data of patients with intrahepatic portosystemic venous shunts was obtained from hospital records. results: We determined 3 patients with intrahepatic spontaneous portosystemic venous shunts. Although portosystemic venous shunts could lead to hepatic encephalopathy, all of the patients we studied were asymptomatic. One of the patients had a small shunt related to portal hypertension. The other two patients had no additional abdominal pathologies. Conclusion: MDCT can be used to identify asymptomatic small intrahepatic portosystemic venous shunts, which are probably more common than they are considered to be.

portal venous gas: is sonography a better technique than Ct? P.A. Santos, R. Maia, M. Gomes, J. Pires, F. Reis, M. Ribeiro; Porto/PT Learning objectives: To understand the major causes and mechanisms leading to the presence of gas in hepatic portal system and the role of US and CT studies in this setting based on imaging findings in 6 cases. Background: Presence of gas in the portal vein is a rare entity. Once detected, it should be considered a life-threatening event until proven otherwise, depending, above all, on the underlying aetiology. Intestinal necrosis is the leading cause of portal venous gas (PVG) and is associated with higher mortality rates. First reports of PVG were based on plain film findings, which have a poor sensitivity. The advent of sonography and CT allowed the detection of smaller amounts of gas in the portal system. Imaging findings or procedure details: PVG was considered present when sonography showed multiple high-amplitude echoes moving within the lumen of portal vein in the direction of blood flow. At CT, portal vein gas appears as tubular areas of decreased attenuation in the liver, predominantly in the left lobe. In the study group, US proved to be more sensitive than CT in the detection of PVG, which was reported and explained in some previous papers. Conclusion: Recognition of PVG indicates, generally, a life-threatening acute abdominal process. However, this finding is no more than a radiological clue and not a diagnosis. In our experience, sonography proved to be the most sensitive method in the detection of PVG. However, the goal of radiologic techniques, besides PVG confirmation, is to establish the underlying pathological process, which is best carried out by CT.

the significance of the right hepatic artery originating from the superior mesenteric artery in patients with portal vein thrombosis A. Erden, E. Düşünceli, E. Üstüner; Ankara/TR purpose: Dilatation of the hepatic artery in response to the decrease in portal vein flow is known as "hepatic arterial buffer response" (HABR). In this study, the effect of HABR on variant hepatic arterial anatomy is investigated by analyzing the frequency of right hepatic artery originating from superior mesenteric artery (variant artery) and by searching dimensional relationship exists between variant artery and common hepatic artery (CHA) in patients with portal vein thrombosis (PVT). (group I, n=24), with recanalized PVT (group II, n=11), and without PVT (group III, n=55). results: The mean diameter of the CHA and variant artery in group 1 was significantly (p<0.01) larger than that of the control group. The mean diameter of the CHA in subjects with the variant artery was significantly smaller (p<0.05) than that of the subjects without variant artery when all groups were taken into account. The area under the ROC curve (0.906±0.075) indicated that the variant artery was a significant parameter (p<0.01) at separating the patients with and without PVT. Conclusion: In conclusion, HABR is effectual on variant artery in patients with PVT.

evaluation of portal venous velocity with doppler Us in patients with nonalcoholic steatohepatitis S. Ulusan, T. Yakar, Z. Koc; Adana/TR purpose: The aim of our study was to determine the relationship between portal venous velocity and hepatic-abdominal fat evaluated in patients with nonalcoholic steatohepatitis (NASH) using spectral Doppler US recordings and MRI. material and methods: In this prospective study, 35 patients with NASH and 29 normal healthy adults who served as control group underwent portal Doppler US. The severity of hepatic steatosis in patients with NASH was assessed by MRI through chemical shift imaging using a modification of Dixon Method. Abdominal (intra-abdominal and subcutaneous) fat was measured using MRI. results: The difference in the portal venous velocity between the patients with NASH and the control group was significant (p<0, 0001). There was not any correlation between the degree of abdominal or hepatic fat and the portal venous velocity (p>0, 05). Conclusion: Patients with NASH have a lower portal venous velocity than normal subjects.

Contrast-induced nephropathy following the intravenous injection of iso-osmolar and low-osmolar contrast media: a pooled analysis H.S. Thomsen 1 , S.K. Morcos 2 , C.M. Erley 3 , L. Romano 4 , D. Sahani 5 ; 1 Herlev/DK, 2 Sheffield/UK, 3 Berlin/DE, 4 Naples/IT, 5 Boston, MA/US purpose: To compare the incidence of contrast-induced nephropathy (CIN) after administration of low-osmolar contrast media (iomeprol-400 or iopamidol-370) or iso-osmolar iodixanol-320 in patients with chronic kidney disease undergoing MDCT. material and methods: 301 patients with CrCl < 60 mL/min received LOCM (n=153), or IOCM (n=148) in two double-blind studies. A subset of patients (n=67; LOCM, n=52; IOCM) had CrCl <40 mL/min and SCr >2.0 mg/dL. All patients received a similar CM dose (40 gI) IV at 4 mL/s. Blood samples were collected predose and at 2-3 days postdose for SCr determinations in the same central laboratory. CIN endpoint was an increase in SCr >0.5 mg/dL from baseline. Baseline patient characteristics were compared using a chi-square test or the unpaired t-test, as appropriate. CIN rates were compared using a chi-square test. results: The two groups were comparable at baseline for all the variables tested. A significantly greater change in SCr from baseline was seen in patients receiving IOCM compared with patients receiving LOCM (0.05±0.25 vs. -0.02±0.18 mg/dL, p=0.008). The rate of postdose SCr increases >0.5 mg/dL was 4.7% (7/148) after IOCM and 0/153 after LOCM (p=0.007). In patients with CrCl <40 mL/min and SCr >2.0 mg/dL, the rate of CIN was 11.5% (6/52) after IOCM, 0/67 after LOCM (p=0.006). Conclusion: In high-risk patients receiving IV contrast, the rate of CIN may be higher following the IOCM than the LOCM.

radiological characteristics of HCC in children: a 16 year experience in a tertiary paediatric hepatology centre D. Lewis, P.A. Kane;, B. Portmann, M. Sellars, M. Samyn;, N. D. Heaton, J. Karani; London/UK purpose: Hepatocellular carcinoma [HCC] is an extremely rare and commonly fatal malignancy in childhood. Early recognition allows opportunity for surgical cure. We have reviewed our experience in order to define the radiological characteristics of HCC in this population in association with pathological subtype. material and methods: We undertook a retrospective review of clinical, radiological and pathological and surgical data of all children with HCC referred to our unit between 1991 and 2007. The relevant demographics, clinical, pathological and radiological features were documented. results: 30 patients with a mean age of 9.3 yrs and M:F ratio of 13:17 were identified. Pre-operative imaging, including a variable combination of USS, CT and MRI, was available in 26 patients. Lesion size ranged from 7 to 205 mm; mean 82 mm. The tumour was multifocal in 9 and a solitary nodule in 17. In 19 children, arterialisation was a dominant feature, venous or caval thrombosis recognised in 11 and calcification in 8. Lymphadenopathy and distant metastases were a feature in 9 and 6 cases, respectively. CT was the imaging modality most reliably associated with correct diagnosis and pathological sub-type of HCC. Full analysis of results will be presented. Conclusion: Our experience represents the largest series of paediatric HCC in recent times. This presentation illustrates the radiological characterisation of this rare but important tumour.

early postoperative bleeding following living donor liver transplantation: clinical impacts and Ct findings compared with angiography S.S. Hong, A.Y. Kim; Seoul/KR Learning objectives: To illustrate various CT findings of the early postoperative bleeding following LDLT confirmed by angiography. To discuss the clinical impacts of these early postoperative bleedings following LDLT and CT findings or CT angiographic findings compared with angiography according to the various bleeding causes. To evaluate the possible bleeding arteries according to the location of hematoma and contrast leakage on CT scan. Background: Delayed detection of postoperative arterial bleeding following living donor liver transplantation (LDLT) can be fatal because of most of arterial bleeding becomes suddenly descent in hematocrit and hypotensive. As a result, in most of the cases open surgical revision or interventional embolization is needed. Imaging findings or procedure details: The early postoperative bleeding following LDLT can be caused by problems with vascular anastomosis, rupture of a hepatic artery pseudoaneurysm, inferior phrenic artery bleeding, right renal capsular artery bleeding, intercostals artery bleeding after chest tube insertion site, pancreatoduodenal arcades and jejunal branch bleeding, right adrenal hemorrhage, and abdominal wall hemorrhage. In this exhibit, we will discuss the clinical impacts of these early postoperative bleedings following LDLT and CT findings or CT angiographic findings compared with angiography according to the various bleeding causes. Emphasis is laid on evaluation of the possible bleeding arteries according to location of hematoma and contrast leakage on CT scan. Conclusion: On serial follow-up CT images, if there are active bleeding findings including increased in size of loculated hematoma, dilated vascular structure, or the extravasation of contrast media, it should be managed surgically or by transcatheter embolization without delay.

A. Németh, E. Hartmann, L. Kóbori, Z. Gerlei, V. Weszelits, A. Doros; Budapest/HU purpose: The splenic artery aneurysm (SAA) incidence is higher in patients with portal hypertension and cirrhosis than in the average population. The aim of this study is to analyze the results of the clinical and radiological follow up of our liver transplant patients with preoperatively diagnosed SAA. material and methods: From 1995 to 2008, a total of 352 orthotopic liver transplantations were performed in 335 patients at our institute. Pre-and 1-year postoperative CT-angiograms of 306 liver transplant patients, age 12.7-63.1 y (mean: 46.1), female-male ratio 16/9 were reviewed for number, size, location and morphology of SAAs. Underlying liver diseases: postviral cirrhosis (17), primary biliary cirrhosis (3), autoimmune (2) ALD, and congenital fibrosis and B 90 DOI: 10.1007/s10406-008-0008-8

Wilson disease 1 case each. results: Twenty-five patients had 66 saccular aneurysms (size range: 3-35 mm), in 13 patients multiple. Overall incidence was 8.2%. Sixty aneurysms (91%) located in the distal, 6 in the middle third of the splenic artery. The number of large SAA (>2 cm) was 4. One concomitant renal artery aneurysm was found. Radiological or surgical action for rupture prevention happened in 5 patients. With surgical and radiological intervention of SAA we had no rupture. The control angiographies showed no changes in size and number of the untreated aneurysms. Conclusion: Large SAA requires surgical or interventional treatment, although, untreated aneurysms showed no progression, and the patients remained free of symptoms. proposed as diagnostic procedures in order to establish metastatic hepatic disease in patients with treated colorectal carcinoma. The purpose of this study project is to evaluate the use of both procedures in the management of these patients referred to diagnostic accuracy. material and methods: Thirty-two patients (mean age: 62 y; 21 male) under follow-up for colorectal carcinoma with suspicion of metastatic hepatic disease have been sequentially explored in blinded conditions using CEUS and FDG-PET (mean interval: 17.2 d). Standard reference used was: lesion pathology (19/32); intraoperatory US (5/25); follow up (8/25). results: Five patients were free of tumour activity >22 months since initial treatment (true negatives). In three patients, FDG-PET showed systemic dissemination and contraindicated surgery for lesions. In twenty-four patients, CEUS and FDG-PET showed lesions as potentially resectables. Referred to individual lesions (n=68), no tests showed false positives; diagnostic accuracy for lesions was: CEUS: 58 true positive, 10 false negatives (sensitivity: 85%); FDG-PET: 37 true positives, 31 false negatives (sensitivity: 54%), mainly due to the high number of lesions smaller than 10 mm (n=17). Conclusion: Although both methods are quite useful in determining the treatment decision based on a per patient analysis, the preliminary results in this short cohort shows that CEUS helps the surgeons in their surgical attitude, obtaining much more better results than FDG-PET in order to establish the number, size and localization of liver metastasis in patients with treated colorectal carcinoma, which is determinant in surgical assessment.

pattern of enhancement of hepatic metastases on contrast enhanced Us: is the classification in hypovascular and hypervascular still valid? P. Cabassa ). Inclusion criteria were: hystologic (biopsy or surgery) proof of malignancy; no previous treatments with thermal ablation or chemoembolization. When more than one lesion was present, a target lesion was chosen for evaluation. CEUS was performed during continuous real time scanning with second generation contrast media (Sonovue) at the standard dose of 2.4 ml with specific contrast settings at low mechanical index (0.1-0.2). Data were recorded prospectively and analyzed retrospectively. Patterns of enhancement were assessed lesion by lesion during arterial, portal and late phases. results: 57/71 (80.3%) lesions showed enhancement during arterial phase. In 42/57 nodules, the enhancement was homogeneous and in 15/57 inhomogeneous. In 41/55 lesions, the enhancement was particularly strong in the early arterial phase (within 20 sec) compared to the late arterial phase. Arterial phase enhancement was present also in well known hypovascular metastasis (i.e. colorectal). All lesions had wash-out during portal and late phases becoming hypoechoic to the surrounding liver. Conclusion: Most of metastases showed arterial enhancement. Contrary to MDCT and MR, the classification in hypovascular and hypervascular on CEUS is therefore debatable.

Characterization of focal liver lesions: contrast-enhanced Us versus mdCt and mr T.V. Bartolotta Boston, Policlinico Umberto I, University La Sapienza, Rome, and Policlinico San Matteo, Pavia) were reviewed to evaluate the imaging findings of patients with histological proven hepatic adenoma studied with CEUS at low-MI (0.06-0.2). CEUS multiparametric behaviour was analyzed. Conclusion: 24/25 (96%; 95% CI=80.5-99.3%) showed high intensity of enhancement as scored as 3, while only one (4%; 95% CI=0.7-19.5%) was classified as score 2. The time of contrast arrival ranged between 10 and 19 sec (average 13). All but one of the 25 lesions (96%; 95% CI=80.5-99.3%) showed early homogeneous enhancement during hepatic arterial phase. Nor portal venous phase enhancement was observed in any lesions as all showed rapid washout (100%; 95% CI=86.7-100%). Twenty lesions (80%; 95% CI=60.9-91.1%) were found to be iso to slightly hypoechogenic in the portal phase and 19 were (76%; 95% CI=56.6-88.5%) iso to mildly hypoechogenic whereas 6 lesions (24%; 95% CI=11.5-43.4%) were hypoechogenic during the later phases. 

Hepatocellular cancer response to radiofrequency tumor ablation: contrast-enhanced Us T.V. Bartolotta, A. Taibbi, M. Galia, G. Malizia, G. Lo Re, M. Midiri, R. Lagalla; Palermo/IT Learning objectives: To illustrate the spectrum of CEUS findings in the assessment of RFA therapeutic response of HCC. Background: Radiofrequency ablation (RFA) is increasingly being used as percutaneous treatment of choice for patients with early-stage hepatocellular carcinoma (HCC). An accurate assessment RFA therapeutic response is fundamental, since a complete tumor ablation significantly increases patient survival, whereas residual unablated tumor needs an additional treatment. Recently, contrast enhanced ultrasound (CEUS) has become available for RFA assessment. Advantages and limitations of CEUS are described on the basis of a series of 337 RFA treated HCC. Imaging findings or procedure details: At CEUS, a complete response is the absence of enhancing portion within or at the margin of the ablation zone during the hepatic arterial phase (HAP). Residual unablated tumor is the persistence of an irregular hypervascular area within the treated HCC in the HAP, either located within the edge (ingrowth) or around a treated nodule, and in continuity with its border (outgrowth). A uniform and thin peripheral rim of contrast enhancement surrounding the ablated zone in a rindlike fashion should be regarded as benign reactive hyperaemia, whereas a transient hyperechoic area in the HAP may be an arteriovenous shunting. Conclusion: Awareness of CEUS findings make the radiologist to confidently detect residual disease after RFA of HCC, thus allowing retreatment even in the same RFA session and resulting in a better patient management.

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Withdrawn by authors diagnostic / other / acute and post-traumatic abdomen P-213 plain abdominal radiograph: still useful in the era of mdCt E. Kelliher, G. Albuquerque, A. Alzahrani, H. Khosa, P. Mc Carthy; Galway/IE Learning objectives: To provide a pictorial review of GI and abdominal conditions that may be diagnosed from the PFA (plain abdominal radiograph). To describe and explain the relevant radiological signs. To highlight the value of continuing to perform this simple quick non-invasive non-contrast inexpensive low dose examination, which may, in some cases, render CT unnecessary. Background: Because of the superior diagnostic sensitivity and specificity of MDCT and its increasing accessibility, patients presenting with an acute abdomen often proceed directly to CT without first having a plain abdominal radiograph (PFA). It is worth remembering that CT has disadvantages, specifically: radiation dose, contrast and cost. Many causes of acute abdominal pain can be ascertained by examining the PFA. Imaging findings or procedure details: Pictorial review of PFAs with CT correlation demonstrating causes of abdominal pain suggested/diagnosed from a PFA through analysis of bowel gas pattern (small/large bowel obstruction, gallstone ileus, gastric/caecal/sigmoid volvulus, congenital malrotation, hernias, intussusception, Hirschsprungs), abnormal gas shadows (aerobilia/portal venous air/intramural air), abnormally located soft tissue (masses/abcesses), abnormal bowel wall (inflammatory bowel disease, ischaemic/pseudomembraneous colitis), abnormal calcific densities (appendicolith, biliary calculi, pancreatic calcification, hepatic hydatid disease) and foreign bodies. Conclusion: Radiologists should promote awareness among clinicians of the continued value of requesting and examining the PFA and radiologists themselves should do so when accepting requests for other modalities as the diagnosis may be apparent from the PFA.

the imaging approach to right sided abdominal pain A. Tokala, D. Kasir, S. Sukumar, V. Rudralingam; Manchester/UK Learning objectives: 1. To discuss the value of cross sectional imaging in the work up of RSAP. 2. To demonstrate the imaging features of common and unusual alternative diagnosis encountered. 3. To describe the potential imaging pitfalls seen on US and CT. Background: The management of patients with right sided abdominal pain (RSAP) is increasingly dependant on the imaging findings. The inappropriate choice of imaging modality can lead to misinterpretation. US is the established first line imaging modality in suspected cases of acute cholecystitis and appendicitis. In the appropriate clinical setting, further cross sectional imaging with CT should be performed. Imaging findings or procedure details: 1. The spectrum of imaging findings and pitfalls in common causes of RSAP such as acute appendicitis and acute cholecystitis will be presented. 2. An emphasis will also be placed on the unusual causes of RSAP, for example, acute right sided adrenal hemorrhage, omental infarction, acute appendigitis and right sided diverticulitis. Conclusion: The appropriate use of US and CT ensure the clinical triage of patients into the correct treatment pathway. This enables the accurate differentiation between surgical and non surgical candidates.

torsion of spleen: a Ct diagnosis A. Ben Ely, S. Strauss, G. Gayer; Zerifin/IL purpose: The purpose of this presentation is to report the CT features of splenic torsion, a rare condition which presents as an acute abdomen. material and methods: The US and CT studies of five patients with surgically proven torsion of the spleen were reviewed. All patients presented with severe abdominal pain. US was the initial study performed in all patients, followed by CT within the next 24 hours. results: US showed a mildly enlarged spleen in three patients. Diminished blood flow on Doppler examination was noted in one case. The spleen was thought to be in its usual location and the diagnosis of torsion of the spleen was not suggested. On CT, a more caudal location of the spleen in the left midabdomen was detected in four patients. Postcontrast CT showed complete lack of enhancement of the splenic parenchyma in three patients, patchy enhancement in one, and very poor, but homogeneous, enhancement in one, indicating partial or complete infarction. A "whirl" appearance representing the twisted splenic pedicle was seen in four patients. Emergency surgery in the five patients confirmed the diagnosis of splenic infarction caused by torsion. Four patients underwent splenectomy and the one of them underwent detorsion with splenopexy. Conclusion: Imaging plays an essential role in the diagnosis of torsion of the spleen and prompt diagnosis is crucial in order to preserve the spleen.

acute abdomen in non-traumatic patients: spectrum of mdCt findings and clinical correlation according to the causes of inflammation and neoplasm and localization of solid and hollow viscera K.N. Jee, K.H. Lee, Y. Kim; Cheonan/KR Learning objectives: To understand the characteristic CT findings and pitfalls of AA in non-traumatic patients according to the inflammatory, neoplastic, vascular causes and localization of solid and hollow viscera 2. To evaluate the correlation of CT findings and clinical severities or medical and surgical conditions in nontraumatic AA. Background: Acute abdomen (AA) is needed to recognize and understand characteristic CT findings and pitfalls of AA in non-traumatic patients according to the various causes and localization of solid and hollow viscera and to evaluate the correlation of MDCT findings and clinical severities or medical and surgical conditions in non-traumatic AA. Imaging findings or procedure details: 1. Cause and localization; acute (infectious/vascular) inflammation, calculous/tumorous/mechanical obstruction, exacerbation or relapse of chronic inflammation and vascular accidents due to underlying conditions in solid organs of liver, pancreatobiliary and genitourinary systems, hollow viscera and mesentery, etc. 2. Correlation of imaging and clinical severity; medical condition of acute inflammation, emergent interventional B 92 DOI: 10.1007/s10406-008-0008-8 conditions of obstruction of viscus with vascular accident, etc. Conclusion: MDCT is very helpful to localize and differentiate causes such as calculous/tumorous/mechanical obstruction, exacerbation or relapse of chronic inflammation and vascular accidents due to underlying conditions in solid organs of liver, pancreatobiliary and genitourinary systems, hollow viscera and mesentery, etc. CT findings should be considered combined with clinical findings when we decide the treatment option because clinical and radiological severities are relatively well correlated.

air in strange places on the plain abdominal radiograph E. Kelliher, H. Khosa, T. Ramadan, M. Browne, P. Mc Carthy; Galway/IE Learning objectives: To highlight the importance of identifying abnormal gas shadows on the PFA. To outline the features of such abnormal gas shadows to facilitate recognition and accurate reporting. To demonstrate the variety of pathology that can cause such appearances. Background: Prompt recognition of abnormal gas patterns on the plain abdominal radiograph (PFA) is vital to minimise morbidity/mortality. Serious abdominal pathology such as intestinal perforation may be silent when the patient is elderly, on steroids, or unconscious/critically ill/post trauma and so the appreciation of abnormal gas patterns becomes even more important. Imaging findings or procedure details: Air on the PFA is normally confined to the lumen of the GI tract. In a variety of serious pathological conditions, air may occur within solid viscera or within the walls of a viscus (eg. emphysematous choecystitis or pyelonephritis, abscesses, necrotizing enterocolitis), it may escape into the peritoneal cavity (pneumoperitoneum), or it may occur within the biliary system (aerobilia), portal venous system, abdominal wall (abscesses, hernias) or retroperitoneum. We provide a pictorial review and discussion of possible appearances of pathological gas shadows on the PFA with reference to anatomical structures. Conclusion: Important pathology may be diagnosed from this simple, quick, inexpensive non-contrast examination through recognition and correct interpretation of abnormal gas shadows. Correct interpretation of the PFA can facilitate further investigations/management and lead to speedier patient diagnosis and treatment.

Imaging of the acute abdomen in haematology patients H.G. Delaney, S.A. O'Keeffe, M.T. Keogan; Dublin/IE purpose: To review the radiological findings in patients with haematological disorders presenting with acute abdominal pain and to determine which particular pathologies and imaging features are more common or unique to this cohort of patients. material and methods: A retrospective review of all haematology patients (39) presenting with acute abdominal pain over a nine month period who underwent cross-sectional imaging with CT was performed. The clinical details, radiological findings and final diagnoses were correlated and the imaging features were reviewed. results: There were a wide variety of presentations and causes for acute abdominal pain. Some were related to tumour burden including painful organomegaly, bowel obstruction and acute urinary obstruction (11). Others were related to treatment or complications of treatment including graft versus host disease of bowel and neutropenic colitis (12). Two patients developed splenic infarction, while three patients had spontaneous retroperitoneal bleeds. Pathology unrelated to the haematological diagnosis or its treatment was demonstrated in three patients. Conclusion: Cross-sectional imaging of the acute abdomen is being performed more commonly in patients with haematological disorders. There are a wide variety of causes of abdominal pain including those directly related to disease bulk and complications of treatment. A number of pathologies are unique to, or more common, in these patients and consideration of this with knowledge of the relevant radiological findings is essential in reaching the correct diagnosis. Background: The initial goal in treatment of patients with gynaecologic malignancies, particularly ovarian cancer, is optimal cytoreduction surgery including total abdominal hysterectomy with bilateral salpingo-oophorectomy, appendicectomy, total infragastric omentectomy, peritonectomy limited to the pelvis, the paracolic gutters, and infiltrated diaphragmatic areas, bowel resection limited to the rectosigmoid, if necessary, and removal of bulky lymph nodes to the infrarenal para-aortic level. Morbidity and several complications are possible in the acute phase post surgery. Imaging findings or procedure details: CT imaging is accurate for evaluating the complications in acute phase post major gynaecologic surgery as fistulas (genito-urinary, uro-enteric, entero-cutaneous); vascular complications (retroperitoneal hematoma, hemoperitoneum, renal infarction); dehiscence (anastomotic, cutaneous); and gastro-enteric complications (gastroparesis, intestinal infarction, perforation, occlusion). Conclusion: Major gynaecological surgery (MGS) is nowadays more commonly performed, especially in oncologic disease, as far as surgical and chemioradiation treatments are improving the patients' survival. Abdominal complications after MGS are not uncommon and may be more severe if not promptly diagnosed. CT, if correctly performed, may be useful for diagnosis, grading and follow-up of such complications. Knowledge of the CT appearance of these complications strongly helps in a timely and correct diagnosis.

Comparison of observer performance in a non-traumatic acute abdomen Ct setting: a prospective study N.H. Stauffer, P.R. Rau, A. Tempia, C. Picht, D. Guntern, E. Melloul, N. Kotzampassakis, T. Prot, C. Vallet, S. Schmidt, A. Denys; Lausanne/CH purpose: Emergency room reading performances have been a point of interest in recent studies comparing radiologists to other physician groups. Our objective was to evaluate the reading performances of radiologists and surgeons in an emergency room setting of non-traumatic abdominal CTs. material and methods: Ten readers representing four groups participated in this study: three senior radiologists and visceral surgeons, and two junior radiologists and surgeons. Each observer blindly evaluated 150 multi-slice acute abdominal CTs. The chosen cases represented established proportions of acute abdominal pathologies in a Level-I trauma center. For statistics, each answer was then transformed into a score ranging from 0=all false to 3=all correct. The gold standard was the intraoperative result or the clinical follow-up for non-operated patients. results: Senior radiologists had a mean score of 2.38±1.14, junior radiologists a score of 2.34±1.14, whereas senior surgeons scored 2.07±1.30 and junior surgeons 1.62±1.42. No significant difference was found between the two radiologist groups, but results were significantly better for senior surgeons as compared to junior surgeons and for the two radiologist groups as compared to each of the surgeon groups. Conclusion: Abdominal CT reading in an acute abdomen setting should continue to rely on an evaluation by a radiologist, whether senior or junior. Satisfying reading results can be achieved by senior visceral surgeons, but junior surgeons need more experience for a good reading performance. the main imaging and diagnostic procedure for evaluation of patients with acute vascular splancnic disease. However, in the last years the advanced technology of the CT showed to have a great potentiality in preoperative and pre-interventional evaluation of this kind of patients in Emergency. Imaging findings or procedure details: MDCT examinations considered were performed in emergency in our institution. All patients underwent multi-phase CT scan of the abdomen and pelvis, using a thin collimation and slice thickness. Intravenous contrast administration was performed in all cases. Post processing imaging reconstruction and evaluation were made at a dedicated workstation. Vessel lumen opacification and features, viscera enhancement and appearance as well as the comparison with additional diagnostic, interventional and surgical procedures have been considered. Conclusion: MDCT could be considered a valuable diagnostic tool in evaluation of patients with suspected splancnic acute vascular disease. Accurate clinical diagnosis is difficult and often unreliable. Imaging, which is routinely requested, has been shown to minimise delay in surgery, reduce unnecessary admissions, and lower patient mortality. Radiologists must therefore understand the various imaging algorithms including when and how each modality is best utilised, as well as interpret the imaging correctly. This educational poster discusses relevant potential pitfalls -including choosing the incorrect investigation, technical errors resulting from contrast administration, phase and timing of imaging, and varied interpretation pitfalls such as missing subtle pathology and misinterpretation of normal findings and abnormalities. Imaging findings or procedure details: We illustrate the potential pitfalls in imaging the acute abdomen with specific examples and provide learning points for both trainees and consultants, including self assessment cases. Conclusion: Radiologists make a series of complex diagnostic decisions during the patient pathway from initial referral through to image interpretation. An awareness of how to avoid pitfalls at each stage reduces possible life threatening errors. Discuss when is appropriatre to perform MDCT and when US may replace it in post-traumatic abdomen evaluation. Background: To assess, describe and illustrate US and MDCT findings in the course of abdominal trauma studied in the Emergency Radiology Department, indicating the fundamental role of both imaging modalities and giving the radiologic/surgical correlation of each finding. Imaging findings or procedure details: MDCT represents the gold standard diagnostic method in the course of abdominal trauma. The fundamental findings illustrated are represented by free fluid in the abdomen, liver, splenial or other parenchimal partial or complete lesions, vascular damages, bone fractures and GI involvement. For each we present the correlation with the surgical detection. We furtherly discuss whether US has to be performed preliminarly and if constrat enhanced US may, in some cases, replace MDCT examination. Conclusion: During the course of abdominal trauma, patients may require an emergency surgery depending on findings that can be provided by different imaging modalities. US is extremely accurate in revealing free fluid into the abdominal cavity but is less accurate than MDCT in detecting parechimal lesions. MDCT represents a complete and fast imaging modality in the detection of findings fundamental for the patient clinical course. US may, in some cases such as minor traumas, repalce MDCT in the evalution of abdominal injuries. B 94 DOI: 10.1007/s10406-008-0008-8 the diverse diseases causing LLQ abdominal pain. Imaging methods help to establish a correct diagnosis and to differentiate between benign self-limited disorders and those which require immediate intervention. CT and US are the modalities of choice. Apart from the common renal and gynaecologic diseases, diverse bowel and omental lesions are also included in this exhibit. Conclusion: Understanding of the imaging findings of these various diseases causing LLQ abdominal pain will prove instrumental in early diagnosis and thus proper management. This exhibit provides a practical easy-to-follow algorithm for radiologists that simplifies the imaging recommendations for left lower quadrant pain.

plain radiographs of emergency surgical admissions: Who is responsible for these? A. Kirwadi, V.B. Pakala, S. Evans; Swansea/UK purpose: The present workload, working pattern and shortage of out-of-hours staffing does not allow radiologists to report all the plain radiographs immediately. The main objective of the study was to evaluate how many radiographs have been reviewed by the referring clinical team, by a radiologist and note any serious discrepancies between those reports. material and methods: 100 consecutively admitted acute surgical patients requiring a plain radiograph were included in our study. Case notes were reviewed to see if the radiographs were reviewed by the clinician and their findings noted. This was compared with the radiologist report for any significant discrepancies. results: 60% of the films were reviewed by the referring clinicians while the radiologist reported on 73%. 14% of films were neither reported by the clinician nor the radiologist. Only 2 minor discrepancies were noted. Conclusion: The IRMER 2000 guidelines state that clinical evaluation of each medical exposure must be made and recorded by both 'the referrer' and 'the practitioner'. We hope that better documentation by clinicians and implementation of PACS will help in reaching this target. Few similar studies have shown that the discrepancy rate between the clinician's and the radiologist's report is very small. Should we restrict the reviewing of films only to those where a clinician is not confident? Developing guidelines with regards to this would help in utilising the available resources for maximum benefit.

Ct findings of bowel and mesentery and solid organ injury following abdominal and pelvic trauma S.Y. Park 1 , S.S. Hwang 1 , Y. Ku 2 , Y.J. Lee 3 , J.Y. Byun 3 ; 1 Suwon/KR, 2 Uijeongbu/KR, 3 Seoul/KR Learning objectives: 1. To understanding of image findings of abdominal and pelvic trauma for the purpose of correctly diagnosing and suggesting a guideline for treatment. 2. To demonstrate image findings of various abdominal and pelvic trauma on CT. 3. To discuss the clinical impact according to variable image findings. Background: CT plays an important role not only for the detection of abdominal and pelvic injuries but also for their appropriate management. In order to make the best use of CT, the radiologist should be aware of the appearance of various types of abdominal and pelvic injuries and the findings that indicate surgery or that may warrant repeat CT studies for monitoring of expectant management. Imaging findings or procedure details: Bowel and mesenteric traumatic lesions include contusion, hematoma, partial or full laceration of the bowel circumference, and bowel transection. Injuries of the mesentery may affect the vascular structures and thus lead to either bleeding or vascular occlusion with subsequent necrosis and eventual perforation of the corresponding bowel structure. Traumatic lesions of solid organ include spleen, liver adrenal gland, kidney pancreas, and urinary bladder. Conclusion: CT of the trauma patient has become an important diagnostic tool that allows for appropriate triage of these patients. Knowledge of the various appearances of the posttraumatic abdomen and pelvis on CT scans is essential so that the patient can be afforded prompt and effective treatment.

Contrast induced nephropathy following I/V contrast: absence of evidence is not evidence of absence S. Krishan, J.A. Guthrie; Leeds/UK purpose: The use of contrast media (CM) is common in abdominal CT. Whilst there are data on the incidence of contrast-induced nephropathy (CIN) following cardiac angiography, the incidence of CIN after intravenous CM administration is less well established. The purpose of this retrospective study was to assess the incidence of CIN in an inpatient population. material and methods: Consecutive inpatients undergoing intravenous CM enhanced CT from 1st July 2006 to 31st December 2006 were investigated. Serum electrolytes and creatinine before and up to 7 days after intravenous CM were assessed. CIN was defined as an increase of the serum creatinine-level of >0.5 mg/dl or >25% above baseline within 48 hours after contrast agent administration. results: 2876 patients were investigated. 85% CT studies were of the abdomen and pelvis. Manifest CIN was seen in 26 patients (0.9%). In those patients who had pre CT creatinine > 250 mmol/L, the incidence increased to 4.6%. A transient rise in serum creatinine (less than 25% above pre-CT value returning to the pre CT levels within a week) occurred in 78 patients (2.7%).

The study population is uncontrolled but unwell enough to occupy a hospital bed and therefore the results are likely to overestimate the incidence of CIN. CIN is an uncommon complication. Intravenous CM seems to be safe and should not be withheld if diagnostically indicated.

richter's hernia after laparoscopy C. Lam, R. Santos, J.M.G. Lourenço, P. Gil, I. Oliveira, Z. Seabra; Lisbon/PT Learning objectives: We report a case of Richter's hernia after laparoscopy, showing the relevance of CT in the diagnosis, along with a brief literature review. Background: Richter's hernia is a rare entity and is the protrusion and/or strangulation of only part of the circumference of the intestine's antimesenteric border through a rigid small defect of the abdominal wall. There are only a few references about Richter's hernia after laparoscopy since the first description in 1977. These hernias may rapidly pass into gangrene, yet signs of intestinal obstruction are often absent. Richter's hernia could be life-threatening if the correct diagnosis and early surgery are not performed. CT is the method of choice in the diagnosis. Imaging findings or procedure details: A 52-year-old woman with a history of gastro-esophagic reflux surgery by laparoscopic three weeks earlier presented to the emergency department with an acute onset of abdominal pain, anorexia and nausea. A palpable mass was found in the lower right abdomen. Abdominal CT demonstrated a Richter's hernia of part of the ascending colon through a trocar site. Surgery confirmed the diagnosis and the patient recovered well. Conclusion: Although Richter's hernia is still associated with a relatively high mortality rate, CT plays an important role in the correct and early diagnosis, allowing prompt treatment.

Ischemic hepatitis: an unusual presentation of celiac artery compression syndrome B. Yagci, N. Karabulut, S. Akalin, G. Onem, Y. Kiroglu; Denizli/TR purpose: To present imaging findings of a unique case of celiac artery compression syndrome (CACS) in whom massively increased serum transaminase levels (STL) normalized rapidly after surgical division of median arcuate ligament (MAL) fibers. material and methods: A 26-year-old male patient with known chronic hepatitis-B presented with abdominal pain, weight loss, and elevated STL. Contrastenhanced abdominal multislice-CT performed during inspiration showed normal findings. However, the symptoms including "food fear" continued to worsen over the following days. STL increased 10-times during this period. surgical division of MAL, STL normalized rapidly and the patient experienced dramatic relief of all symptoms. Conclusion: Hypoxic (ischemic) hepatitis is defined as a massive but rapidly reversible increase in STL due to an imbalance between hepatic oxygen supply and demand. The postoperative decrease in STL suggested ischemic hepatitis due to the CACS. To our knowledge, this association in non-transplant patients has not been reported before. CACS may induce an ischemic hepatitis-like picture, particularly in cases with chronic liver disease. Because the diagnosis of CACS can be overlooked at the routine inspiratory CT, particular attention should be paid to tailor the imaging protocols to include expiratory scan sets. In this exhibit, we will describe the concept of expandable plane (interfascial plane) in which rapidly growing fluid collections may accumulate through the review of embryology and imaging findings. Imaging findings or procedure details: CT observations demonstrated that the rapidly accumulating fluid collections or hematoma tend to escape the retroperitoneal site of origin into laminar variably fused and potentially expandable interfascial planes. Between these planes, potential communicating spaces exist. These are represented by retromesenteric plane (anterior fusion space), retrorenal plane (posterior fusion space) and lateral conal plane. Interfascial fluid collection can spread from the abdominal retroperitoneum into the pelvis along retromesenteric plane and retrorenal plane that form the combined fascial plane at the level of the iliac fossa. Conclusion: The knowledge of embryology and anatomy of interfascial plane and their interconnection is helpful for the radiologist to determine the extent and spread pathways of the retroperitoneal diseases. B 96 DOI: 10.1007/s10406-008-0008-8 (potencial spaces) is essential for accurate evaluation of retroperitoneal disease extension, such as inflammatory or infectious conditions, tumors and traumatic lesions. Imaging findings or procedure details: Abdominal CT is the major imaging modality to approach retroperitoneal pathological processes. Pancreatitis, perirenal hematomas, duodenal perforation with pneumoretroperitoneum, colonic diseases (such as retrocecal appendicitis, infiltrating neoplasms and ischemic colitis), abdominal aortic aneurysm rupture and metastatic tumoral spread are some of the nosologic entities revisited. Conclusion: Embryologic, anatomic, clinical and imaging evidences exist that retroperitoneal fluid collections and infiltrating diseases may rapidly extend to a contiguous space or interfascial plane or even to the pelvis and mediastinum. A review of these data allows a better spread pattern understanding.

radiation dose during follow up of acute pancreatitis S. Stojanovic, V. Njagulj, S. Senicar, D. Hadnadjev; Novi Sad/RS purpose: In Serbia, there is no regulation or survey control about the amount of radiation received by a patient in any period of time. The aim of the study is to analyse retrospectively the mean dose, length of scanning and DLP during the period of one year in patients with diagnosis of acute pancreatitis (AP). material and methods: 154 patients (104 male), mean age 54.4±14.7, were examined on 64 MDCT scanner. The entire abdomen is examined, performing all unenhanced and enhanced scans in parenchymal phase. Data is shown in the form of volumetric "CT dose index (CTDI)", "ScanLength (SL)" and "DLP (doselength product)". results: The patient with AP undergoes CT examination usually more than once (1.8). Per phase, average CTDI, in total was 18.9±10.7 mGy, ScanTime 10.8±6.0 sec, and DLP 263.6±323.6 mGycm. No significance is noted regarding the age group. Average values per phase, during one examination, were CTDI 10.63±4.204mGy, ScanTime 6.31±1.5 sek, DLP 68.58±34.48 mGycm. Female patients had significantly longer scanning time, and male patients had significantly higher CTDI value. DLP did not differ between sexes. Low dose protocols were not used. Conclusion: The national survey program has to be established in order to follow the effective doses from CT examination in different hospitals and to correct and unify the examination protocols with lowest average radiation dose. 

Ct pulmonary angiogram: a novel approach to GI imaging? S. Chawla, D.P. Mullan, A. Camenzuli; Liverpool/UK Learning objectives: To familiarize the radiologist with subtle review areas and pathologies within the GI system as imaged on CTPA examinations. To argue the case for reduced reliance on protocol based investigations and to suggest the need for thorough clinical evaluation prior to imaging. Background: Computed Tomography Pulmonary Angiograms (CTPAs) have become the main stay of investigation of suspected pulmonary thromboembolism. The classical symptoms of pleuritic chest pain and shortness of breath are notoriously non-specific in clinical practice. Radiologists are aware of the low positive predictive value of the D-dimer assay. Historically, it is well recognized that GI disease can mimic pulmonary pathology both symptomatically and biochemically. The increasing availability of imaging and D-dimers has arguably led to reduced reliance on clinical examination. This has lowered the threshold for performing CTPAs with positive findings often only identified in the GI system. Imaging findings or procedure details: We present in pictorial fashion, a selection of CTPA studies in which the cause of the symptoms and biochemical abnormalities are shown to be due to GI pathologies. We provide selected images of infective, inflammatory and neoplastic processes with reference to salient clinical and anatomical considerations. Conclusion: CTPAs are frequently carried out for GI pathologies. This in retrospect could have been suspected clinically, thus negating the need for an imaging modality involving significant ionizing radiation to the chest.

staging of rectal cancer: how accurate is mrI? M.G. Mulla, R. Deb, R. Singh; Derby/UK purpose: Rectal cancer ranks as the third commonest tumour of the GI tract. With high recurrence rates (30%), accurate staging of these tumours is essential to prevent recurrences. MRI scan is proven to be effective; however, it is important to understand its limitations. material and methods: 40 consecutive patients with rectal cancer were included in this retrospective study. All images were reported by two radiologists imaging and all specimens were reported by two histopathologists. MRI staging done preoperatively was compared to post surgery histology staging. results: There were 25 males and 15 females with a median age of 70.5 years. Overall agreement in staging (TNM) between the two was 30% (n=12). T stage agreement was assessed by Kappa coefficient (k=0.4583). Sensitivity and specificity for T staging was 0.89 (0.74, 0.96) and 0.67 (13, 0.98), respectively. PPV and NPV for T staging was 0.85 (0.69, 0.94) and 0.15 (0.06, 0.30), respectively. CRM status was accurately staged, except in one patient (94.1%). Accuracy for lymph node staging was 47.5%. Conclusion: MRI proved very sensitive in identifying the CRM which remains the main factor affecting the outcome of surgery. Differentiating T2 from early T3 still remains a problem as is with T1 and T2 tumours. Identification of involved nodes is also difficult unless they show similar signal characteristics as the tumour. The use of 'paramagnetic iron oxide' MR may be helpful in future.

sickle cell disease: spectrum of mrI appearances of the spleen and relevance to clinical management S. Sawhney, R. Jain, S. Al-Kindi; Muscat/OM Learning objectives: The spectrum of MRI morphology of the spleen in Sickle cell disease (SCD) reflecting the pathophysiology of splenic sequestration, infarction and 'autosplenectomy'. Background: Contrary to popular belief, the spleen in SCD does not just 'disappear' (or autosplenectomise). It has varied appearances which may be mistaken for serious pathology and result in unnecessary surgery or splenectomy. Imaging findings or procedure details: Retrospective analysis of MRI of the abdomen performed in 69 patients of SCD referred for evaluation of bone pains as part of an ongoing project to study the temporal progression of changes in spleens of patients of SCD. Six of these patients had had prior splenectomy. In the remaining 63 patients (age mean±SD 23.3±7.7), a splenic volume of eight to 1546 ml (mean±SD 341.1±291.5) was recorded. The spectrum of splenic morphological appearances ranged from (in increasing order of severity of involvement): a) simple splenomegaly; b) splenomegaly with peripheral nodular or triangular areas of sequestration/infarction leading to small contracted ferrocalcific spleens; c) enlarged hypointense spleens secondary to transfusional iron overload without/with focal nodular areas of (regenerative) functional splenic parenchyma; d) normal sized markedly hypointense spleens reflecting large volume sequestration; and e) small ferrocalcific spleens. Conclusion: Splenic morphology in SCD is varied and reflects the pathophysiology of SCD. Awareness of the patterns seen and correct interpretation of morphology can help in preventing unnecessary splenectomy.

Unusual abdominal and pelvic localizations of non-Hodgkin's lymphoma: Ct and mrI examination technique and imaging findings M. Missere, G. Restaino, E. Cucci, A. Pierro, M. Barrassi, G. Giordano, S. Storti, G. Sallustio; Campobasso/IT Learning objectives: The major teaching points of this exhibit are: Apart from typical appearance, NHL may be found in unusual localizations. Both CT and MRI provide useful information for diagnosis and staging of abdominal and pelvic unusual localizations of NHL. Knowledge of the CT ad MRI appearance of unusual localizations of NHL strongly helps a timely and correct diagnosis. Background: Non-Hodgkin lymphomas (NHLs) are frequent tumors. However, extraglandulary forms are very unusual, and the location in some organs is extraordinary. In this exhibit, we will describe the epidemiology, classification, pathophysiology and clinic features of NHL. We will also describe CT and MRI technique and imaging findings in unusual abdominal and pelvic localizations of NHL. Imaging findings or procedure details: Epidemiology, classification, pathophysiology and clinical features of NHL. CT and MRI technique for evaluation of abdominal and pelvic NHL. Review of CT and MRI findings in unusual abdominal and pelvic localizations of NHL: liver; biliary tree; gallbladder; spleen; kidney; pancreas; stomach and bowel; ovary and female urethra. Conclusion: NHL may present in unusual abdominal and pelvic localizations. Radiologists must be aware of these unusual localizations and their CT and MRI appearance in order not to miss crucial diagnostic findings and not to misinterpret the imaging examination results.

Ct and mrI spectrum of presacral lesions Z. Jiang, W. Peng; Shanghai/CN Learning objectives: To present the spectrum of CT and MRI findings of presacral lesions. To help develop an imaging algorithm in making a specific diagnosis with clinical and pathologic correlation. Background: Primary presacral masses may arise from rectum, ovaries, pelvic soft-tissues, or retroperitoneum, and patients with pelvic carcinoma can develop presacral metastasis or recurrence. The differential diagnosis for presacral masses is extensive. The diagnosis can be suggested depending on lesion features and relationship with adjacent organs. We reviewed CT and MRI findings of presacral masses in patients examined at our institution from January 2003 to November 2007 with correlation of symptoms and pathology. Imaging findings or procedure details: Clues of differential diagnosis include special components (fat, calcification, mucus, hemorrhage, necrosis, etc.), contour, pattern of enhancement, and relationship with rectum or sacrum. We present and discuss the imaging features of various presacral masses, which originate from rectum (stromal tumor, adenocarcinoma), ovaries (teratoma, cystadenoma), pelvic primary masses (neural tumor, liposarcoma, leiomyosarcoma, lymphoma, perivascular epithelioid cell neoplasm), metastatic or recurrent tumours, and non-neoplastic lesions such as endometrial cyst and abscess. Conclusion: A wide variety of lesions occur in the presacral space. The knowledge of imaging characteristics and clinicopathologic behavior of these lesions allows the diagnosis and may suggest an adequate treatment. To exhibit the implementation of diffusion-weighted imaging (DWI) with the use of apparent diffusion coefficient (ADC) measurements in the study of variable (histologically proven) abdominal lesions. material and methods: Single-shot echo-planar DWI was added to the routine abdomen MR examination in 61 patients with abdominal lesions. Quantitative analysis of ADC was made by region of interest measurements in normal and pathologic tissue of different abdominal organs (liver 24, pancreas 2, kidney 4, adrenal 7, bowel 8, ovaries 3, bladder 1, peritoneum 3 patients). results: The mean ADC of malignant lesions was in all occasions lower than that of benign lesions. The mean ADC value of liver was 1.31 (x 10-3 mm 2 sec-1), of the spleen 1.23, of the kidneys 2.25, of the adrenals 1.85 and of the pancreas 1.71. Liver ADCs showed no significant difference from 6 hepatocellular carcinomas or 11 metastatic lesions (1.64). ADC in 6 patients with colon tumor recurrences 1.13, one pancreatic cancer 1.45, one adrenal metastasis 1.32 (no significant difference from 5 adenomas -1.31). Conclusion: ADC calculation of abdominal organs and lesions 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. Further accumulative experience is needed to define the ranges of pathologic in each occasion.

abdominal wall: a pictorial review of the normal anatomy and pathology J.C. Quintero, D. Hernández, I. Urra, L. Castro, I. Guasch, C. Pozuelo; Badalona/ES Learning objectives: The aim of this exhibit is to review normal anatomy of the abdominal wall by CT and to present the more usual pathologies of the abdominal wall diagnosed in our institution. Background: We revised all of the reports of five years old of abdominal CT made in our institution. 9525 reports of abdominal CT were performed in the last four years at our institution. We encountered 302 cases (3.17%) of pathology of the abdominal wall and retrospectively reviewed two senior experienced radiologists who were unaware of CT findings from the other. Usually the studies consist: oral contrast, 5 mm collimation, pitch: 1.5, 100 ml of contrast medium, rate: 2.5 ml/sec, delay: 70 sec. We illustrate the most representative images that show the abdominal wall and its components: muscles, fascias layers, aponeurosis, ligaments, skeletal, vessels and nerves. Imaging findings or procedure details: Herniary pathology (194): Spigelian, inguinal, incisional, lumbar, etc. Not herniary pathology (108): congenital lesions (urachal abnormalities and omphalomesenteric duct abnormalities), fluid collections (haematoma, abscess and cellulites and urinoma), neoplasm (primary malignancies, metastatic disease and benign lesions) and miscellaneous (vascular lesions, vascular grafts, calcifications and subcutaneous gas). Conclusion: Cross-sectional imaging provides an excellent, non-invasive means of evaluating these processes. Specific observations on the nature, location, extent, and underlying causes can be made, therapy planned and instituted, and follow-up accomplished.

that the radiologist should know about the spleen? J.C. Quintero, C. Roqué, D. Hernández, A. Olazábal, I. Guasch; Badalona/ES Learning objectives: 1) To illustrate the spectrum of congenital and acquired abnormalities spleen. 2) To determine the current role of US, CT and MRI in the detection and characterization of focal spleen lesions. Background: The spleen has the same relationship to the circulatory system that the lymph nodes have to the lymphatic system. A wide range of splenic variations and abnormalities can affect the spleen and may be detected on abdominal imaging while one simultaneously evaluates the remaining intraabdominal structures. Imaging findings or procedure details: We reviewed retrospectively 51 patients with normal, splenic variations and abnormalities spleen diagnosed in our institution. We present a comprehensive algorithmic approach to diagnose various abnormalities of the spleen: 1) Normal anatomy and congenital variations (11); 2) Traumatic conditions (9); 3) Vascular affections (5); 4) Infections (4); 5) Cysts (5); 6) Benign neoplasms: hemangioma (3), hamartomas (1), lymphangiomas, and inflammatory pseudotumor (1); 7) Malignant neoplasms: primary, lymphoma (5), and metastasis (4); and 8) Miscellaneous conditions: sarcoidosis (1), amyloidosis (1), thorotrastosis, and extramedullary hematopoiesis (1). Conclusion: In discussing the normal anatomy, congenital variations, and acquired abnormalities such as those resulting from trauma, infection, infarction, cysts, and neoplasm. US, CT and MRI all play an important role in the detection and characterization of focal splenic lesions, and with sufficient clinical information they enable the differential diagnosis of these lesions.

mesenteric tumors: Ct findings of primary and secondary tumors and differential diagnosis A. Lourbakou, A. Anagnostara, S. Mylona, S. Ntai, A. Katsarou, N. Batakis; Athens/GR purpose: CT is the main method in establishing the diagnosis of mesenteric tumors. Though the primary mesenteric tumors are rare, mesentery is commonly affected by metastatic or inflammatory lesions of the peritoneal cavity. The purpose of this study is to present the imaging findings of these entities. material and methods: In a 12-month period, 23 patients with CT findings of mesenteric tumors were studied in our department.results: Three of them were diagnosed with primary tumors (lipoma, desmoid tumor and sarcoma). The diagnosis was confirmed by CT guided biopsy. Seven of them had typical imaging findings of mesenteric lipodystrophy. There was no need for histological confirmation. One patient was diagnosed with carcinoid tumor, one with GIST, four presented with peritoneal spread from ovarian and GI tumors, two suffered from lymphoma, one from amyloidosis with mesenteric infiltration, one from tuberculosis, and one from mesenteric metastasis of melanoma. In one out of 23 patients, mesenteric multiple abscesses were observed and one patient presented with echinococcus cyst with mesenteric spread. CT revealed the mesenteric pathology in all cases. The imaging findings of the above mentioned entities in correlation with the rest of the clinical findings had led in certain cases to the differential diagnosis. Conclusion: CT imaging with or without CT-guided biopsy is efficient in establishing the diagnosis in mesenteric disease.

normal anatomic relationship of peritoneal reflections and diseases of peritoneum using multiplanar images Y. Kim 1 , S.Y. Song 2 , O.K. Cho 2 , B.H. Koh 2 ; 1 Kuri/KR, 2 Seoul/KR Learning objectives: To display normal peritoneal reflections using multiplanar images. To illustrate usual and unusual peritoneal diseases. To find the imaging characteristics of individual disease. Background: Omentum, mesentery, ligaments and peritoneum are anatomically complicated areas to fully assess CT images. Peritoneum can be affected by various diseases, and several different forms are manifested. Imaging findings or procedure details: We reviewed normal peritoneal reflection, ligament, mesentery and omentum using multiplanar CT images. We classified MDCT findings of peritoneal disease as follows: disseminated, nodular, cystic forms. Selected cases are presented and the imaging characteristics are discussed. Peritoneal diseases include inflammatory diseases (tuberculous peritonitis, bacterial peritonitis, and actinomycosis) and peritoneal carcinomatosis (disseminated, nodular and cystic type). Conclusion: A review of the normal peritoneal anatomy, the pathology and imaging characteristics of disseminated peritoneal disease is presented. Although these CT appearances overlap, classifying them by pattern is helpful in narrowing the range of the differential diagnosis. 

Ct-imaging of splenic lesions S. Ntai, S. Mylona, G. Karapostolakis, A. Anagnostara, A. Katsarou, N. Batakis; Athens/GR Learning objectives: Computed Tomography (CT) is an excellent imaging modality for demonstrating the size, shape and position of the spleen as well as for depicting intrasplenic pathologic features. The purpose of this study is to discuss the congenital and acquired abnormalities of the spleen and present their CT appearance. The examination technique and contrast protocol are also part of this presentation. Background: The medical records of 91 patients (55 men, 36 women, age range 18-76, mean age 56.4 years) with intrasplenic lesions were retrospectively reviewed. Location, enhancement patterns, presence of calcifications or cystic components was in all cases evaluated. Imaging findings or procedure details: The clinical history of the patients must always be taken into consideration since the imaging findings of different entities may be overlapping. The abnormalities encountered and described in this study include congenital variations, traumatic and infectious lesions, vascular abnormalities, benign and malignant neoplasms, whereas the cases presented demonstrate both the value and the limitations of the method. To determine whether MRI can measure adrenal gland volume (AGV) in normal human volunteers and to determine the intra and inter-observer variations and repeatability. material and methods: This was a simple single cohort, sequential design, 2 part study involving 4 MRI examinations per subject. Part 1: subjects underwent a single MRI examination to determine feasibility for the technique. Part 2: the volunteers were examined twice in one day (1 hour apart) and again one week later. Information was collected on four healthy subjects (three male and one female). Two different investigators estimated the area of the adrenal gland for each of the 3 mm contiguous slices on two separate occasions. The volume of the adrenal gland (in cm3) was calculated. To estimate inter and intra reader variability, a repeated-measures mixed model was fitted with adrenal volume as the dependent variable. In order to estimate any bias between readers, Bland-Altman methodology was applied. results: Total volume variation from all sources is approximately 14% of a 3 cm 3 adrenal gland. Variation over time is small (5% of a 3 cm 3 adrenal gland). Variation due to within and between investigator is larger (9% of a 3 cm 3 adrenal gland). Image reading by a second investigator could reduce variability. Conclusion: MR analysis of AGV is suitable for detecting incremental changes within the range seen in adrenal gland disease.

Ct imaging of hernias in the inguinal region S.A. Joffe 1 , V. Hatzoglou 2 , S. Okon 2 , M. Horowitz 2 , Z. Patel 2 ; 1 Bet Shemesh/IL, 2 New York, NY/US Learning objectives: 1) To review the anatomy of the inguinal region. 2) To demonstrate the CT anatomy and CT imaging features of hernias in the inguinal region. 3) To demonstrate CT imaging features of complications of these hernias. Background: Evaluation of hernias in the inguinal region is a common indication for CT imaging of the abdomen and pelvis. In addition, CT frequently detects these hernias incidentally. Imaging findings or procedure details: Knowledge of the anatomy of the inguinal region including normal CT anatomy is essential for differentiating the different types of hernias. CT imaging techniques for evaluating inguinal hernias include the valsalva maneuver. CT can differentiate among indirect inguinal hernias, direct inguinal hernias, and femoral hernias. CT helps demonstrate the contents of these hernias, including fat, fluid, bowel, bladder, and ovary. In addition, CT can identify complications of inguinal hernias, including incarceration, strangulation, and bowel obstruction. Conclusion: This exhibit will explain how to differentiate indirect and direct inguinal hernias and femoral hernias on CT, how to identify structures within these hernias, and how to recognize complications of these hernias.

Imaging diagnosis of sclerosing peritonitis and its complications D. Emlik, M. Yeksan, I. Guney, O. Koc, S. Gumus, K. Odev; Konya/TR purpose: Sclerosing peritonitis (SP) is a rare but serious complication of chronic ambulatory peritoneal dialysis that occurs with an incidence of between 0.06 and 7.3%. The purpose of this study was to discuss serious complications such as small bowel, large bowel obstruction, necrosis and peritoneal thickening. material and methods: A 33 years-old woman with chronic renal failure involvement having CAPD for ten years was presented. Plain films of abdomen, ultrasonography and abdomen CT were performed. results: Enhanced abdominal CT showed dilatation of small and large bowels. Enhanced abdomen CT also revealed enhancement of the peritoneal membranes, peritoneal thickening and presence of intraperitoneal fluid collection. Moreover, there were peritoneal and vascular calcifications in association with liver and splenic capsule calcifications. Such radiological changes in this patient on peritoneal dialysis were consistent with a diagnosis of SP. The patient's condition deteriorated during the peritoneal dialysis and died due to infection. The SP diagnosis was suggested by imaging findings and confirmed by peitoneal biopsy. Conclusion: Although a rare complication, small and large bowel obstruction due to SP should be considered in any patient on prolonged ambulatory peritoneal dialysis. CT is an accurate method for early diagnosis and follow-up of SP.

the various manifestations of extra-nodal lymphoma in the abdomen and pelvis: a pictorial review A. Rajesh, R. Kirke, R. Verma; Leicester/UK Learning objectives: To illustrate and discuss the different manifestations of extra-nodal lymphomatous involvement in the abdomen and pelvis. Background: Malignant lymphomas are differentiated into Hodgkin's and non-Hodgkin's-lymphoma (NHL). Lymphoma can affect nearly all tissues and involve extra-nodal locations. This review describes the typical and rarer atypical manifestations of abdominal lymphoma involving the solid abdominal viscera and bowel. Imaging findings or procedure details: Extra-nodal involvement from lymphoma can affect any organ and can present as isolated organ involvement or as a part of multi-organ involvement. The use of MDCT is increasing in the evaluation of the abdomen and a variety of lymphoproliferative pathology is being detected either as an incidental finding in an acute abdomen or a part of a diagnostic work up. Imaging also aids in the staging of the disease and in detection of related complications. We discuss and review the radiologic appearances of histopathologically proven cases of extra-nodal lymphoma in the abdominal viscera, gastrointestinal tract and in rarer locations such as the B 101 postgraduate Course

Lunch symposia scientific sessions epos™ presentations authors' index DOI: 10.1007/s10406-008-0008-8 by multiple abscesses, draining sinuses, and abundant granulation tissue. It shows infiltrative nature and easily invades normal anatomic barrier, cross fascial planes, and invade multiple compartments. Its imaging findings overlap with neoplastic and inflammatory conditions. Imaging findings or procedure details: We reviewed the CT and MRI of 15 patients with abdomiopelvic actinomycosis. The involving sites were appendix (1), appendix and cecum (1), omentum (1), urachal remnant (2), and ovary (10). Appendiceal actinomycosis shows thickening of appendix. Actinomycosis of appendix and cecum shows bulbuous thickening of appendix with contiguous cecal thickening. Actinomycosis of omentum shows bulky infiltrative solid mass with dense enhancement and multiple small abscess cavities, contiguous with the transeverse and ascending colon. Actinomycosis of urachal remnant shows infiltrative densely enhancing mass with infiltrative border with multiple small abscess cavities along urachal course. Ovarian actinomycosis reveals unilateral or bilateral adnexal mass with pure cystic or solid and cystic mass with infiltrative border. Conclusion: Abdominopelvic actinomycosis involves many organs. Awareness of its characteristic imaging findings can help in the differential diagnosis of abdominal and pelvic mass.

Withdrawn by authors P-265 normal anatomy and various abnormalities of the splanchnic arteries: mdCt angiography and 3d imaging H.Y. Han, S.J. Park, H.S. Choe; Daejeon/KR Learning objectives: To review the MDCT angiographic and 3D images of the normal anatomy, anatomical variant, and various abnormalities involving splanchnic arteries. Background: To review imaging findings of the normal anatomy, anatomical variant, and pathologic processes involving celiac trunk and mesenteric arteries. Imaging findings or procedure details: Review of MDCT imaging findings of the various abnormalities involving celiac trunk and mesenteric arteries. 1. Normal anatomy and anatomical variant -celiomesenteric trunk with/without aneurysm, superior mesenteric artery (SMA) syndrome, intestinal malrotation. 2. Acute arterial impairment -Celiac trunk dissection, isolated SMA dissection, thromboembolism, traumatic vascular injury. 3. Chronic arterial insufficiency. 4. Inflammatory or tumorous conditions affecting celiomesenteric arteries. Conclusion: MDCT angiography and 3D images allow for optimal depiction of the anatomy and its anatomical variant of the celiac trunk and mesenteric arteries and show various causes of the vascular impairment.

Imaging spectrum of the extraabdominal mass lesions at the pelvic component of the conventional abdominopelvic cross-sectional examinations D. Yildirim 1 , H.T. Sanal 2 , M. Tasar 2 , M. Kocaoglu 2 , B. Tiryaki 1 ; 1 Istanbul/TR, 2 Ankara/TR Learning objectives: In the pelvic region, with abdominopelvic CT imaging other than gastrointestinal, urinary and genital systems, a diversity of lesions can be seen. Background: In abdominopelvic cross sectional imaging, a spectrum of pathologies other than gastrointestinal and urogenital systems can be seen in pelvic region. We aim to classify pelvic mass lesions which do not correspond with their prediagnoses. Imaging findings or procedure details: 290 cases which have been reported as having pelvic masses on CT between May 2005 and June 2007 were reviewed respectively. With the pathology reports of 23 cases and 2 years follow up results of the rest, the imaging protocols, prediagnoses, and the images were rereviewed. Conclusion: Neoplastic mass lesion (n=71) (32 benign, 24 primary malignancy of the bone and soft tissues around the pelvic rim, 15 metastatic lesion), infectiousinflammatory mass (n=54), postoperative-posttravmatic changes (n=68), Paget disease (n=1), fibrous dysplasia (n=1), pelvic lipomatosis (n=1), bone island (n=29), Klipel-Trenaunay Syndrome (n=1), bone variation (n=59), and pelvic kidney (n=5) were found. Extraintestinal, extraurinary and extragenital masses comprised 4.2% of the 6900 cases.

Bilateral extraadrenal perirenal myelolipomas: Ct features O. Temizoz, H. Genchellac, M.K. Demir, E. Unlu, H. Ozdemir; Edirne/TR purpose: The purpose of this report is the demonstration of CT findings in this disease. material and methods: Abdominal computed tomography (CT). results: Myelolipomas are rare, benign tumors composed in varying proportions of adipose tissue and hematopoietic cells. These lesions are typically found in adrenal glands. However, they are rare in extra-adrenal sites and are difficult to diagnose with imaging studies. The unusual location of these tumors present an imaging studies challenge. Distinguishing these lesions from other tumors including adipose tissue and hemopoietic cells may also be difficult even at pathologic examinations. The distinction between extra-adrenal myelolipomas and malignant tumors such as liposarcomas is crucial to avoid an invasive procedure. Although sporadic case reports involving perirenal sites of myelolipomas have surfaced in the literature, only a case of bilateral extraadrenal perirenal myelolipomas with imaging findings have been reported to date. Conclusion: We herein present a comprehensive report of the CT imaging characteristics of a pathologically proven case of bilateral extraadrenal perirenal myelolipomas.

Withdrawn by authors P-269 optimization of scanning parameters of 64mdCt of abdomen and pelvis P. Paolantonio 1 , R. Ferrari 2 , P. Lucchesi 2 , F. Vecchietti 2 , M. Maceroni 2 , A. Laghi 2 ; 1 Rome/IT, 2 Latina/IT purpose: We propose a scanning protocol optimized for abdomen and pelvis evaluation using a 64MDCT scanner. material and methods: On a 64MDCT scanner, we optimized the following protocol for abdomen and pelvis evaluation: detector configuration: 64 x 0.625; 120 kv; for tube current setting a smart-mA system were used (range 100-800 mA); noise index 28; pitch 1.3. This scanning protocol was acquired before and during i.v. administration of iodinate contrast medium. Hepatic arterial phase, portal venous phase and equilibrium phase were acquired using a bouls-tracking system for hepatic arterial phase acquisition with 15 sec. of delay between aortic threshold of 100 HU. We used this scanning protocol in 150 patients referring for abdomen and pelvis CT scan. Data sets were transferred on a off-line workstation with MPR and VR capabilities. Image analysis was performed increasing the slice thickness from the native 0.4 mm up to 2.5 mm. Image analysis was performed from two radiologist in consensus and was focused to a quantitative assessment of image quality of both axial images and MPR reconstructions. results: Image quality referring to image noise of both axial and MPR reconstructions was judged optimal in all cases. The isotropic voxel properties lead to an optimal quality of the MPR reconstruction. Conclusion: The scanning protocol proposed for 64MDCT scanner in the evaluation of abdomen and pelvis enables optimal image quality and excellent spatial resolution on z-axis.

Chronic hepatic venous outflow obstruction: Us in the diagnosis and rationalizing approach towards management R. Jain 1 , S. Sawhney 1 , S.K. Acharya 2 ; 1 Muscat/OM, 2 New Delhi/IN purpose: To identify the spectrum of Ultrasonographic findings in chronic hepatic venous outflow obstruction (HVOO). material and methods: A prospective study on 100 consecutive patients aged 3 to 69 years (mean±SD 27.1±11) with histologically proven HVOO. US was performed in all patients. Inferior-venacava (IVC) angiograms were performed in B 102 DOI: 10.1007/s10406-008-0008-8 40 patients for correlation with US, including 26 endovascular interventional procedures. results: With IVC angiograms as gold standard, US was 100% sensitive for diagnosis of HVOO; and site, type and severity of IVC abnormality. US provided additional information about liver parenchyma, hepatic-veins (HV) and intrahepatic collaterals. Three distinctive types of IVC/HV disease were identified: Type I-22/100 patients-Membranous occlusion of the IVC at cavo-atrial junction by 2.1±.08 mm thin membrane; Type II-72/100 patients-Steno-occlusive narrowing -41±25 mm long-of intrahepatic IVC 1 cm below cavo-atrial junction; Type III-6/100 patients -IVC was normal. All types were associated with hepatic vein abnormalities of varying severity. Types I and II showed significant differences in age at presentation 35.23±8.66 v/s 25.13±10.83 years (p<0.001), HV abnormalities-HV score 4.18 v/s 6.43 (p<0.001), and response to endovascular therapy, respectively. Conclusion: US is adequate for diagnosis and classification of HVOO into: Type I -Membranous, and Type II -Steno-occlusive IVC abnormalities. Percutaneous interventional procedures are most effective for Type I disease, and less so for Type II. US is helpful in the diagnosis of HVOO and rationalising patient management.

Causes and patterns of abdominal lympadenopathy in pediatric patients M.G. Papadaki Athens/GR Learning objectives: To present the different causes of AL in children. To highlight the specific characteristics of the lymph nodes. To emphasise the importance of additional findings that may assist in the correct diagnosis. Background: Abdonimal lymphadenopathy (AL) is a very common finding during abdominal ultrasonography in pediatric patients. A clinical context explaining the cause is often difficult to define, while location, characteristics and additional findings may help to narrow the differential diagnosis. Imaging findings or procedure details: Several pathologic conditions cause AL, the most common being viral mesenteric adenitis. Of inflammatory nature are also lymph nodes accompanying appendicitis and Crohn's disease. Non-Hodgkin lymphomas of the bowel are the most common malignancy manifesting with AL while other malignancies may also spread through abdominal lymph nodes. When studying enlarged lymph nodes, it is mandatory to define their location, either intra-or retroperitoneal. Specific characteristics should be examined: their size and shape, the presence or absence and the thickness of the nodal hilum, the structural pattern of the cortex and the blood flow patterns. Ultrasonographic evalution should include all abdominal solid organs, components of the peritonal cavity, the retroperitoneum and the bowel wall looking for evidence that may contribute to the diagnosis. Conclusion: Knowledge of differential diagnosis in pediatric patients with AL, specific characteristics of the lymph nodes and additional findings may contribute significantly to the correct diagnosis.

role of endoanal Us in the management of women with clinical diagnosis of 3rd/4th degree obstetric-related perineal tears K. Thiruppathy, R. Cohen, A. Emmanuel, S. Halligan, S.A. Taylor; London/UK purpose: To correlate endoanal USS findings with symptoms and anal manometry in women with clinical diagnosis of 3rd/4th degree obstetric-related perineal tears. material and methods: 101 consecutive women with clinically diagnosed 3rd/ 4th degree obstetric tears (and undergoing primary repair) underwent endoanal US, anorectal physiology (resting and squeeze pressures) and completed bowel function scores (Wexner incontinence scores). Comparison was made between women with radiologically confirmed 3rd/4th tears with ultrasonically intact sphincters (1st/2nd degree tear) using chi square testing and unpaired t testing as appropriate on statistical advice. results: US revealed that 32/101(32%) had no evidence of sphincter injury (i.e. 1st/2nd degree tear). Significantly, more women reported faecal incontinence (FI) in the group with actual sphincter injury (61 vs 34%, p=0.01). 14% (10/69) of those with ultrasonically confirmed tears had persisting sphincter defects despite primary repair. Anal resting pressure was not significantly different both between the 3rd/4th and 1st/2nd degree tear groups (59 vs 65 mmHg, p=0.13), but squeeze pressure was lower in those with confirmed 3rd/4th tears (57 vs 73 mmHg, p=0.003). Conclusion: One-third of patients clinically diagnosed with 3rd/4th degree tears in fact have intact sphincters on US. This group report less FI and retain a stronger anal squeeze pressure than those with ultrasonically confirmed sphincter disruption. Endoanal US has an important role in the correct management of patients even with clinically diagnosed sphincter disruption.

relapse of autoimmune pancreatitis N. Takahashi, S.T. Chari, A. Sugumar, J.G. Fletcher, A. Kawashima; Rochester, NY/US purpose: To evaluate the patterns of relapse in patients with autoimmune pancreatitis (AIP) and to identify findings at presentation that may predict the relapse. material and methods: 70 patients with AIP who had follow-up imaging study were included. Imaging studies at presentation were evaluated for pattern of pancreatic involvement and presence of extrapancreatic involvement. Serum IgG4 levels and mode of treatment were recorded. Follow-up imaging studies were evaluated for presence of relapse or progression of AIP. Findings at presentation were compared between patients with and without relapse. results: Median follow-up duration was 13 months (1-146 months). 26 (37%) of 70 patients had relapse or progression of AIP. 12 patients had relapse in biliary tree, 11 in pancreas, 8 in kidney, and 4 in other organs (2 in lung, 2 in liver, 1 in pleura, 1 in retroperitoneum). Relapse in organs that were uninvolved at presentation was uncommon. Relapse occurred between 6-60 months (median 19 months). When compared between patients with and without relapse, mean age (60 vs. 59 y-o), mean serum IgG4 levels (446 vs. 453 mg/dL), pattern of pancreatic enlargement (diffuse/focal/normal-atrophy: 48/22/30% vs. 36/28/15%), or presence of extrapancreatic involvement (biliary/kidney/ retroperitoneum: 71/33/17% vs. 56/34/13%) at presentation and mode of treatment (steroid/surgery/none: 58/27/15% vs. 64/25/11%) were not significantly different. Conclusion: Relapse of AIP is relatively common. It is difficult to predict the relapse of AIP from the findings at presentation.

evaluation of age-related changes of pancreatic tissue on diffusion weighted mrI S. Bayramoglu, O. Kilickesmez, N. Guner, T. Cimilli, G. Yirik, S. Aksoy, E. Hocaoglu; Istanbul/TR purpose: Pancreas demonstrates significant morphological changes during the life. The dimensions and weight of pancreas begin to increase in newborn till adulthood and it gradually decreases after the fourth decade. The morphological changes were reported on US and CT imaging while the cytologic changes were declared only in autopsy series. The purpose of our study was investigate the reflection of these changes on diffusion weighted MRI (DWI-MRI). material and methods: One hundred and forty patients aged between 1 and 87 were studied in a consecutive series. Patients with major abdominal, major-minor hepatopancreaticobilier pathologies and history of diabetes, pancreatitis and alcohol abuse were excluded. ADC measurements of pancreatic head, corpus and tail were recorded. The mean ADC value was calculated for each patient. The statistical differences of ADC values and sex differences were investigated in each decade. Each decade was compared using Oneway Anova and Post Hoc Tukey HSD tests. The correlation between age and pancreatic ADC values was evaluated with Pearson correlation analysis. results: Mean ADC values of pancreas showed a linear negative correlation after third decade (r:-0.842; p:0.001; p<0.01). ADC values of each decade were different and the differences were more significant in doubling decades (p<0.01). There was no significant difference between males and females. 

What is the role of diffusion-weighted mrI in the evaluation of pancreatic carcinoma? T. Cimilli, N. Guner, S. Bayramoglu, E. Öztürk, A. Kayhan, O. Kilickesmez, A. Karahasanoglu; Istanbul/TR purpose: The aim of this study was to demonstrate the feasibility of body diffusion-weighted (DW) MRI in the evaluation of presence and extent of pancreatic carcinoma (PC). material and methods: DW images were obtained on axial plane scanning with a single-shot echo planar spin-echo sequence with a body coil in fifteen patients with PC and in fifteen normal volunteers aged same as those of patient group. We measured the apparent diffusion coefficient (ADC) value in a circular region of interest (ROI) within the normal pancreas in control group and within the PC and also the surrounding tissue in patient group. results: On diffusion-weighted images, fourteen of fifteen carcinomas showed high signal intensity relative to the surrounding tissue. The ADC values in the carcinoma were significantly lower compared to that of surrounding tissue and normal pancreas in fourteen patients (p<0.01). In one patient with a diagnosis of mucin-producing tumour, ADC value was significantly higher than normal pancreas. Conclusion: DW images can be helpful in detecting the presence and the extent of PC.

diffusion-weighted mrI of pancreatic tumors F. Kotake 1 , R. Iwashiro 2 , M. Yoshimura 2 , K. Saito 2 , M. Matsushita 1 , Y. Takahashi 1 , T. Ozuki 1 ; 1 Ibaraki/JP, 2 Tokyo/JP purpose: To evaluate the diagnostic contribution of diffusion-weighted imaging using apparent diffusion coefficient (ADC) values to the characterization of pancreatic tumors and differentiation of benign and malignant lesions. material and methods: The study included 27 patients with pancreatic tumors who underwent upper abdominal MRI examinations. Chemical shift selectivediffusion-weighted images were performed with the following parameters: 2600/76/6 (TR/TE/excitations); echo train length 51; slice thickness/gap 5.0 mm/1.0 mm and b-values were set at 0 and 1000 sec/mm². We set the region of interest in the center of the pancreatic tumors, except for cystic lesions and necrosis, and then measured the ADC value. results: The mean ADC values (x10-3mm 2 /sec) were 1.01±0.09 for carcinomas (n=16), 0.58±0.02 for malignant lymphomas (n=2), 0.78 for mucinous cystadenocarcinoma (n=1), 0.95±0.05 for metastatic tumors (n=2), 1.32 for insulinoma (n=1), 1.46 for solid-pseudopapillary tumor (n=1), 1.22±0.11 for autoimmune pancreatitis (n=3), and 1.65 for tumor-forming pancreatitis (n=1). The ADC values in the malignant lymphoma were significantly lower compared to that of the other pancreatic tumors (p=0.0017). The mean ADC value of benign lesions (1.35±0.19) was significantly higher than that of malignant lesions (0.95±0.16) (p<0.0001). When an ADC value smaller than 1.05 was used for predicting malignancy, the diagnostic sensitivity, specificity and accuracy were 86, 100 and 89%, respectively. Conclusion: Diffusion-weighted imaging with quantitative ADC measurements can be useful in the differential diagnosis of pancreatic tumors.

pancreatic adenocarcinoma: state of the art imaging using mdCt and mrI M. Zins 1 , I. Boulay-Coletta 1 , L. Huwart 2 , E. Petit 1 ; 1 Paris/FR, 2 Le Kremlin-Bicêtre/FR Learning objectives: To detail state-of-the-art MDCT and MRI protocols in imaging the pancreas for suspicion of tumor. To discuss respective advantages of MDCT and MRI using state-of-the-art 2D and 3D techniques in the assessment of pancreatic adenocarcinoma. To illustrate 64 MDCT and high resolution 3D MRI results in the diagnosis and staging of pancreatic adenocarcinoma. Background: The assessment of pancreatic adenocarcinoma is a difficult challenge for the radiologist and needs state-of-the-art imaging techniques for precise evaluation and adapted therapeutic approach. Imaging findings or procedure details: 1. 64 row MDCT protocol for diagnosis and staging pancreatic adenocarcinoma. 2. MRI protocol for pancreatic imaging with emphasis on new 3D sequences. 3. Case studies of pancreatic cancer with comparison of both modalities. 4. Pitfalls and limitations of CT. 5. Pitfalls and limitations of MRI. 6. Conclusion with diagnostic algorithm. Conclusion: MDCT using 3D multiplanar reconstructions remains the imaging modality of reference in the diagnosis and staging of pancreatic adenocarcinoma. MDCT has the potential to improve the accuracy of pancreatic cancer staging for surgical resectability. However, some limitations and pitfalls still remain and high resolution MRI using new 3D sequences is now a strong competitor for CT.

Withdrawn by authors P-279 prognostic significance of the volume of the primary tumor and metastasis imaging characteristics with survival and pten gene expression in patients with inoperable or metastatic pancreatic cancer treated with gemcitabine combined with gefitinib in a phase II trial A. Kalogera-Fountzila, X. Mavropoulou, E. Psoma, M. Potsi, V. Karadimou, B. Demirler-Simsir, A.S. Dimitriadis; Thessaloniki/GR purpose: To evaluate the response to treatment of inoperable/metastatic pancreatic cancer and correlate the imaging findings with survival and gene profile. material and methods: 54 patients were registered in a phase II study of the Hellenic Cooperative Oncology Group (HeCOG), Athens, GREECE. Gemcitabine (G) (1000 mg/m2) was administered weekly for 7 cycles. Gefitinib (250 mg) was given orally. RESIST criteria were used to evaluate the response to treatment. In 43 patients, the volume of the primary tumor was calculated using Volumio software. results: Ten patients (19%) completed treatment while 36 (67%) progressed before the completion of the treatment. Three patients (6%) had partial response and 11 (20%) had stable disease. After a median follow-up of 9 months, median survival time was 7.4 months, while median time to disease progression (TTP) was 3.9 months. The one-year survival rate was 23%. Neither the volume nor any other imaging characteristic was significant to survival and PTEN expression. We noticed that target and non-target lesions in baseline images had a complete response to therapy, with appearance of new lesions, a fact significantly associated with increased survival (p=0.022). PTEN expression was noticed in 7/30 patients and was the only marker significantly associated with disappearance of old lesions and appearance of new (p=0.003). Conclusion: There are limitations of our study due to the small number of patients. Larger numbers are needed to confirm that gene profile correlates with response to treatment pattern.

Imaging of pancreatoduodenal groove B. Viamonte, L.I. Melão, A. Almeida, M. Castro, N. Silva, R.G. Cunha; Porto/PT Learning objectives: 1. Review the normal anatomy of the PDG. 2. Present imaging features and key diagnostic findings of the diseases involving the PDG. Background: The pancreatoduodenal groove (PDG) is a potential space bordered by the head of the pancreas, duodenum, and common bile duct. Diseases arising from or involving the PDG can be categorized into four types: diseases associated with the pancreas, duodenum, lymph nodes, and distal common bile duct. Imaging findings or procedure details: A didactic format will be utilized and organized based on imaging findings and clinical features. Differential diagnosis with a discussion of specific entities will follow. All patients underwent an MRI examination on a 1.5/3 T system and a CT investigation in a 64 slice scanner. Conclusion: Knowledge of the features of each disease may allow one to make a specific diagnosis, which assists in clinical management and helps to prevent unnecessary surgical intervention. Background: Accessory pancreatic duct (APD), due to hard visibility and presumed lower clinical significance than main pancreatic duct, is usually disregarded by radiologists reporting MRCP. Nevertheless, beside its role in pancreas divisum (PD), its patency lowers the risk of developing acute pancreatitis either spontaneous and after ERCP. Minor duodenal papilla (MIP) is difficult to locate radiologically, but may host diseases, like several types of endocrine tumors, and its function is crucial in PD. Imaging findings or procedure details: We reviewed 200 S-MRCP performed at our Institution from 2004 to 2007 and focused on APD with regard to: visibility, type (long, intermediate, short, ansa), morphology of distal end (stick, branch, saccular, spindle, cudgel), caliber and patency; on MIP with regard to visibility, location, size and morphology. We also assessed the APD and MIP conspicuity in various S-MRCP sequences: T2w-SSFSE, b-SSFP, 2D-MRCP w/o secretin, 3D-MRCP (with MIP, MPR), 3D-LAVA (with minIP, MPR). Conclusion: Morphological and functional evaluation of APD and MIP adds important information to those provided by S-MRCP. Newer MR sequences allow good conspicuity of these structures. Knowledge of normal and variant morphology of APD and MIP is crucial to correct image interpretation.

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Imaging findings of groove pancreatitis V. Tang, K. Uzoka; Manchester/UK Learning objectives: Describe groove pancreatitis and its appearance on various imaging modalities. Background: Groove pancreatitis is an uncommon form of chronic focal pancreatitis that affects the pancreatoduodenal groove between the pancreatic head, duodenum and common bile duct. It causes fibrous scarring of the duodenal wall, smooth stricture of the common bile duct and rarely stricture of the pancreatic duct. Its importance lies in the similarity of imaging appearances to carcinoma of the pancreatic head affecting the pancreatoduodenal groove. Imaging findings or procedure details: We describe our imaging experience of groove pancreatitis in our hepatobiliary unit. We illustrate the varied appearances of groove pancreatitis on CT, MRI and ERCP. A characteristic sheet of mass is noted in the pancreatoduodenal groove which is hypodense on CT, hypointense on T1 and iso to marginally hyperintense to the normal pancreatic parenchyma on T2 weighted images. Cystic changes within and thickening of the duodenal wall are noted. A smooth stricture of the common bile duct is present on MRCP and ERCP. Conclusion: Although certain imaging features can distinguish groove pancreatitis from pancreatic carcinoma, it remains difficult to differentiate the two conditions and histology is often required for correct diagnosis. A mass in the pancreatoduodenal groove in a patient with abdominal pain and vomiting should prompt the radiologist to consider groove pancreatitis as a differential diagnosis in order to avoid unnecessary surgical intervention.

peripancreatic lymphatic invasion of the pancreatic carcinoma: imaging demonstration with multi-detector row Ct M. Sai 1 , H. Mori 2 , K. Kosen 1 , M. Kiyonaga 2 , Y. Yamada 2 , S. Matsumoto 2 ; 1 Yufu-shi/JP, 2 Oita/JP Learning objectives: 1. To understand the normal CT anatomy of PLN. 2. To demonstrate the multi-detector row CT (MDCT) imaging of PLN invaded by the pancreatic carcinoma.Background The peripancreatic lymphatic networks (PLN) are frequently involved with pancreatobiliary carcinoma, affecting the prognosis. However, little attention has been paid to the CT imaging of normal and pathological conditions of PLN. Imaging findings or procedure details: In this education exhibit, we will demonstrate the normal PLN obtained by imaging reconstruction every 1 mm with multiplanar reformation using MDCT. Furthermore, we will review the CT images of PLN invaded by the pancreatic carcinoma. The normal peripancreatic lymphatics were usually detected as "linear structures" on MDCT. On the other hand, the peripancreatic lymphatic invasion of pancreatic carcinoma was frequently identified as "reticular", "tubular" or "soft tissue mass" appearances in the peripancreatic fat tissues on MDCT. The peripancreatic lymphatic invasion of pancreatic carcinoma on MDCT was more frequently detected around the common hepatic artery, celiac artery, and superior mesenteric artery. Conclusion: Knowledge of the CT imaging of normal and abnormal PLN is essential for determining the accurate staging of pancreatic carcinoma.

Imaging acute pancreatitis B. Koo, S. Freeman, A. Shaw; Cambridge/UK Learning objectives: To the review the role of the radiologist in the management of patients with AP. This ranges from establishing the diagnosis and aetiology, the merits of using imaging-based severity scores for prognosis, recognition of complications and, finally, when and how interventional procedures should be performed.Background Acute pancreatitis (AP) is an increasingly common clinical problem which is associated with a significant morbidity and mortality. The radiologist may encounter patients for a number of reasons, from diagnosis to therapy. It is vital that the radiologist and clinician understand when, why and how to image patients optimally, together with the indications and techniques of therapeutic procedures. Imaging findings or procedure details: CT is the mainstay of imaging patients with pancreatitis, with US and MRI reserved for specific indications. This review will demonstrate the findings of AP, the value of imaging-based severity scores, the complications arising and how some of these may be managed by radiological means. We also explore the roles of US, CT and MRI in establishing the underlying aetiology of the disease. Conclusion: The radiologist may play a key role in the management of patients with AP, but in order to fulfil this, one needs to be aware not only of the imaging techniques and findings, but when to initiate intervention.

morphological and functional characterization of mucinous lesions of pancreas: a comparative study of mdCt, pet and fused pet-Ct D. Sahani, N. Sainani, S. Fritz, M. Blake, V. Deshpande, C. Fernandes-del Castillo, A. Fischman; Boston, MA/US purpose: Characterize mucinous pancreatic lesions on MDCT and establish features predicting malignancy. Distinguish malignant lesions, based on increased FDG uptake. Correlate areas of increased FDG activity with morphologic features on MDCT. Compare performance of MDCT, PET and PET-CT. material and methods: 28 suspected mucinous lesions in 20 patients (M:F 9:11, Age 33-84 yrs), evaluated with dual phase pancreatic 16-MDCT with abdomen FDG-PET and surgery, were included in this prospective study. One reader evaluated MDCT features and lesions were categorized into benign/malignant. Another reader analyzed FDG-PET; areas of highest FDG uptake were quantified with standard uptake value (SUV). Areas of increased uptake on PET were correlated with morphological features on MDCT on fused PET-CT images. Pathology served as gold standard. results: Pathologically, 12 lesions were main-duct IPMNs, 12 side-branch IPMNs, 1 MCN, 1 SPPN and 2 unclassified cysts. 21/28 lesions were benign and 7/28 malignant. MDCT accurately characterized lesions in 75%. MDCT features favoring malignancy were gross PD dilatation, thick wall/septae and mural nodule. Areas of increased FDG uptake correlated with thick wall/septae and mural nodule on MDCT. Sensitivity and specificity of MDCT, PET and PET-CT for malignancy were 86 and 91%, 43 and 95% and 86 and 86%, respectively. Conclusion: Dual-phase 16-MDCT reliably characterizes mucinous lesions and prediction of malignancy. Increased FDG uptake is highly specific for malignancy and can complement MDCT to increase confidence of malignancy. 

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Visual assessment of high-b value diffusion-weighted mrI in the differential diagnosis of pancreatic lesions: preliminary results F. Donati, P. Boraschi, R. Gigoni, C. Bertucci, S. Salemi, M.C. Cossu, F. Falaschi, C. Bartolozzi; Pisa/IT purpose: To determine the usefulness of visual assessment of high-b value diffusionweighted MRI (DW-MRI) in the differential diagnosis of pancreatic lesions. material and methods: Ten patients with malignant pancreatic lesion confirmed at surgery (ductal adenocarcinoma, n=8; metastasis, n=1, papillary mucinous carcinoma, n=1) and 15 patients who were being followed-up at our institution because of pancreatic disease other than malignancy (focal chronic pancreatitis, n=2; autoimmune pancreatitis, n=1; IPMT, n=5; serous cystoadenoma, n=5; pseudocyst, n=2) were included in our study group. All patients underwent MRI at 1.5 T device (Signa EXCITE; GE Healthcare). DW-MRI was performed using a breathhold single-shot echo-planar sequence with b gradient factor values of 300, 500, 700 and 1000 sec/mm² in three orthogonal directions. All DW images were blindly interpreted by two reviewers in conference that graded the presence of lesions on a three-point scale on the basis of their signal intensity on high-b value, as follows: 0, absent (no signal); 1, undetermined (mild to moderate signal); 2, present (strong signal). results: The reviewers graded as "2" all adenocarcinomas, pancreatic metastasis and autoimmune pancreatitis (false positive), whereas papillary mucinous carcinoma was defined as undetermined (false negative). All the other pancreatic lesions show "no signal" on high-b value DWI. The sensitivity and specificity of high-b value DW-MRI for the detection of pancreatic malignancy were 90 and 93%, respectively. Conclusion: Visual assessment of high-b value DW-MRI might be helpful in the differential diagnosis of pancreatic lesions.

placement of 85 fiducials in 23 patients under Ct guidance for cyberknife stereotactic radiosurgery of abdomen malignant lesions: an initial experience E. Sotiropoulou, A. Bouga, F. Laspas, N. Salvaras, V. Kosmas, L. Thanos; Athens/GR purpose: The aim of this study is to present our initial experience in positioning gold fiducials as tumor landmarks under CT guidance to facilitate treatment with Cyberknife system of abdomen malignant lesions. material and methods: During the last 8 months, we positioned in our department a total of 85 fiducials in 23 patients. Eight patients had liver metastatic lesions from NSCLC or colon cancer (number of fiducials placed per case: 4, 3, 4, 3, 4, 4, 4, 3), 5 patients had nodes metastases from ovary cancer (number of fiducials placed per case: 2, 3, 3, 3, 4), 3 patients had adrenals metastases from lung cancer (number of fiducials placed per case: 4, 5, 3), 5 patients had pancreatic malignant lesions (number of fiducials placed per case: 3, 4, 4, 4, 4), one patient had retroperitoneal leiomyosarkoma (5 fiducial placed) and one patient had peritoneal sarcoma (5 fiducial placed). Fiducial positioning under CT guidance followed the same procedure as CT guided biopsy. Once the tip was seen at a correct position on CT images, fiducials were advanced through the 18 G Chiba needle. The tip of the needle was readjusted in order to put the fiducials in different sites within the lesion. results: 84/85 fiducials were implanted successfully (98.8%); there was migration of 1 fiducial. Major complications did not occur. Conclusion: Fiducial placement under CT guidance seems to be a safe and efficient procedure.

the appearance and management of colorectal stent complications K. Mason, E.M. Armstrong, J. Shirley, S. Jackson, B. Fox; Plymouth/UK Learning objectives: To illustrate the radiological appearance of the complications associated with colorectal stent placement and demonstrate how the varying complications can be managed.Background In patients presenting with large bowel obstruction, the morbidity and mortality of emergency surgery remains high and self-expanding metal stent insertion is commonly used as an alternative. Stenting can be performed using fluoroscopic or endoscopic guidance or a combination of both. The local complications associated with colorectal stents include rectal bleeding, perforation, stent migration, stent fracture and stent blockage due to tumour in growth. Perforation can be caused by the initial stent insertion, stricture dilatation or due to stent erosion through the colonic wall. It is important that these complications are both detected early and effectively managed in order to optimise a patient's treatment or palliation. Imaging findings or procedure details: We provide a radiological review of the complications associated with colorectal stents and outline the management options available for treating them using video demonstration of the techniques used in our department. Conclusion: It is important that radiologists are able to recognise the complications associated with colorectal stent insertion and appreciate the management options available. This will allow prompt patient treatment and avoid unnecessary delays.

Ct enterographic findings of most common small bowel disorders G. Caruso, G. Salvaggio, S. Pardo, A. Campisi, F. Sorrentino, R. Lagalla; Palermo/IT Learning objectives: CT enterographic findings of most common SBD.Background Increased spatial and temporal resolutions of multi-detector row computed tomography (CT) have made CT a first-line modality for the examination of small bowel disorders (SBD). With large volumes of ingested neutral enteric contrast material, it permits better display of the small bowel lumen and wall. Imaging findings or procedure details: We report CT enterographic findings in the most common diseases encountered in our series, including neoplastic lesions (lymphoma, GI stromal tumor, carcinoid tumor and adenocarcinoma) and nonneoplastic lesions. Non-neoplastic lesions include inflammatory diseases (Crohn's disease, diverticulites and epiploic appendagites) and non-inflammatory diseases (intussusception, volvulus and ischemia). Conclusion: Knowledge of typical imaging features of most common SBD can simplify the diagnosis and be of value in management.

setting up a laparoscopic gastric banding service: implications for the radiology department A.J. Sambrook, A. Thrower, A. Lowe, C. Kay, J. May; Bradford/UK purpose: Laparoscopic insertion of gastric bands is one of several surgical techniques used to treat obesity. Following insertion of a band, radiological inflation/ deflation is necessary in order to ensure optimal function. The purpose of this study is to review our local experience of the implications for the radiology department when setting up a laparoscopic banding service. material and methods: A retrospective audit of gastric bands placed in our institution (April 2005-September 2007) was performed. 19 cases were reviewed. Costs were derived using the business case figures for our institution. results: Mean weight loss was 21.4 kg (range 2-50 kg). The average number of band adjustments was 4 (range 2-9) with a time interval between adjustments of 2-3 months. In 4 cases, urgent band volume reduction was necessary due to complete dysphagia approximately 2 days after the previous adjustment. A single patient needed emergency admission to remove the band due to position slip. The cost per adjustment was €307 with a mean total cost per patient of €1228 (€614-2763). Conclusion: Participation in a gastric banding service requires on average 4 adjustments per case at a cost of €1228 per patient. The requirement for band readjustment and emergency admissions must be factored in when setting up a laparoscopic gastric banding service. B 106 DOI: 10.1007/s10406-008-0008-8

early experience with long dwelling ascitic drainage system V. Arora, A. Razack, G. Alluvada; Hull/UK Learning objectives: Pleurx drain should be considered for palliation of recurrent malignant ascites in terminally ill patients.Background Malignant ascites is a common distressing symptom in cancer patients requiring repeated drainages particularly in later stages due to rapid re-accumulation. Pleurx catheters which are long term indwelling catheters have been used in malignant recurrent pleural effusions. We have used these catheters for relief from malignant ascites. Imaging findings or procedure details: Pleurx drain (Denver biomedical) is a long fenestrated silicon catheter with silicon valve mechanism and a polyester cuff. The two way valve can only open with a specific matched drainage vacuum bottle. We inserted this catheter in ten patients suffering from advanced malignancies for long term ascitic drainage, with US guidance under local anesthesia. Technical success was 100% with no immediate complication. The catheter was tunnelled under the skin and the tube taped to the abdominal wall. As ascites re-accumulates, a vacuum bottle is attached to the tube and further drainage undertaken by the patient, carer or community nurse at home. Follow up showed preference by patients, avoiding repeated interventions and hospital admissions. The catheter has good life span with low complication rate. Conclusion: Pleurx drain can be used for long term palliation of recurrent malignant ascites. It is safe with low complication rate, high technical success rate, avoids repeated hospital admissions and improves quality of life.

esophageal mucocele causing angina symptoms treated with percutaneous drainage K. Güven, E. Terzibasıoglu, A. Ucar, B. Bakır; Istanbul/TR purpose: To stress on the effectiveness of percutaneous drainage of a symptomatic esophageal mucocele. material and methods: A 52-year-old man suffered from chest pain and discomfort after the esophageal resection and colonic interposition operation due to esophageal carcinoma. Electrocardiogram (ECG) revealed ST segment depression suggestive of coronary hypoperfusion. CT examination revealed 58x46 mm well-defined fluid collection at the posterior of the base of the heart next to the thoracic descending aorta. At CT guidance via the intercostal approach, the cavity was punctured and a 6 french locked pig-tail catheter was introduced to the cavity. After the drainage, symptoms disappeared and ECG was returned to normal. results: Esophageal by-pass surgery is performed for benign esophageal strictures, perforations and ruptures, congenital tracheal and esophageal fistulas, esophageal and gastric neoplasms. Blind loop esophageal segments which are ligated proximally and distally contain squamous and glandular epithelium causing secretion collections. They are generally asymptomatic in adults but there are some complications such as infection, ulceration, compression of nearby organs and malign transformation. In our case, the symptomatic esophageal mucocele was treated with percutaneous drainage successfully and did not occur in 6 months follow-up. Conclusion: Percutaneous drainage of esophageal mucoceles after surgery is an alternative treatment to surgery and can be easily performed under CT guidance.

our experience of percutaneous treatment of liver hydatid cysts: 15 years results D. Emlik, D. Kiresi, S. Gumus, K. Odev; Konya/TR purpose: To evaluate the long-term effectiveness of percutaneous treatment of liver hydatid cysts (LHC). material and methods: Sixty one patients with 84 LHC affected by liver echinococcosis were treated using puncture, aspiration injection and reaspiration (PAIR) technique under sonographic guidance. Patients with cysts larger than 6 cm in diameter underwent PAIR followed by percutaneous drainage (PAIR-PD).

The cysts were treated with 20% hypertonic saline solution or 0.5% silver nitrate. All patients went follow-up examinations for 1 month to 6 years after aspiration. Clinical and radiologic examinations and laboratory analysis were performed every month for the first 6 months and then at 3 months intervals. results: A progressive disease in diameter in seventy six cysts (90%); calcification of the cyst wall, cystic or both in five cysts (6%) and complete disappearance of three cysts (4%) in three patients who had been monitored for over 15 years. Five patients developed urticaria, 6 developed fever. One patient developed a biliary fistula after the first aspiration attempt. Two patients developed infection of the cyst cavity after PAIR-PD. Anaphylactic reaction developed in 2 patients and successfully treated with antiallergic medication. Abdominal dissemination was not encountered in any patient over the follow up period of 15 years. Conclusion: Percutaneous treatment of LHC has fewer complications and is much less costly than surgical treatment. This procedure is an effective and reliable treatment in selective cases.

percutaneous treatment of simple liver cysts with alcohol sclerotherapy F. Islim, O. Temizoz, D. Akinci, M.N. Ozmen, O. Akhan; Ankara/TR purpose: To evaluate the therapeutic efficacy of percutaneous treatment of simple liver cysts (SLC) with alcohol sclerotherapy. material and methods: During the period 1993-2007, 31 SLC in twenty six patients (sixteen women, ten men; age range 9-79 years, mean age of 51.2±17.1) were treated by alcohol sclerotherapy. The cyst volumes were 10-1550 mL (mean 188.8 mL). Patients were followed up 1-168 months (mean 46.9 months). 24 of them were treated with single session alcohol sclerotherapy by 19 G needle. Single session catheter drainage and sclerotherapy was performed in 5 cysts. Prolonged catheter drainage and multiple sclerotherapy were applied to two cysts whose volumes were greater than 500 ml. Differences in cystic volumes before and after therapy were examined using the Wilcoxon signed-rank test. results: Technical success was achieved in all patients (100%). The average volume reduction was 93.9% (range 50-100%; p<0.001) in all patients. The mean volume reduction rate was 97% in 25 cysts which were followed for at least 1 year. The remaining 6 cysts with less than 1 year follow up had an 81% mean volume reduction rate. An abscess as a major complication was developed in only one patient who was treated percutaneous drainage and antibiotherapy later. Conclusion: Percutaneous alcohol sclerotherapy is a safe and effective treatment for the management of SLC.

Liver cell transplantation: state of the art J. Tisnado, T. Murphy, U.R. Prasad, R. Fisher, M.K. Sydnor, D. Komorowski, D. Leung; Richmond, VA/US purpose: Orthotopic liver transplantation (OLT) is the definitive method to manage patients with fulminant, acute and chronic liver failure. Unfortunately, organ availability is limited in USA. A "bridge" is needed to keep patients alive until a cadaver or a living donor is found. About 10,000 patients are waiting for a liver. Many will die waiting. Recently, right lobe living donor transplantation (RLLDT) has become accepted and organ pool increased 10-fold. One method to keep patients with fulminant failure alive is liver cell transplantation (LCT), i.e., the hepatocytes infusion from donor livers into the recipient's liver or spleen. material and methods: LCT provides function until a liver is available, or improves function in patients too sick for OLT or RLLDT, in patients with expected 100% mortality in 24 hours. Hepatocytes (200-1000 million) are harvested, cultured, frozen and stored. When needed, cells are thawed and infused in the spleen via splenic artery, or in the liver via the portal vein. Thereafter, hepatocytes colonize in the splenic pulp or hepatic parenchyma and provide hepatic function. results: We performed LCT in >20 patients. We present our encouraging experience. This new method is a "bridge" until OLT and/or RLLDT can be performed. Conclusion: IR must be ready to catheterize the splenic artery or portal vein procedures required on short notice during 24/7. The future of LCT is exciting; therefore, this review. Krausé, B. Chauffert; Dijon/FR purpose: As we previously reported that an in vitro emulsion of pirarubicin, amiodarone and lipiodol was more stable and cytotoxic than a classical doxorubicinlipiodol mixture, we designed a pilot study to evaluate efficacy and toxicity of a transarterial chemoembolization (TACE) procedure using this combination. material and methods: Forty-three patients were included and underwent TACE for unresectable HCC. CT scans were performed to assess tumor response (RECIST) and lipiodol uptake after the first session. Median follow-up lasted 30 months. Endpoints were overall and progression-free survival. Univariate and multivariate Cox analyses were performed. results: Mean tumor size was 9.5 cm (1-20 cm) and 30/43 were multifocal or diffuse. CLIP-score was 0 in 7/40, and 1 in 16/40. Mean number of TACE sessions was 3.5 (1-11). There were 3 treatment-related deaths. Twelve (28%) partial responses and 29 (67%) stable diseases were observed. Median overall and progression-free survivals were 29 months (95% CI 13.8-45) and 15 months (95% CI 11.5-20.8), respectively. CLIP-score ≤1 (p=0.042) and lipiodol uptake>25% (p=0.003) were independent prognostic factors for better overall survival. Conclusion: This new TACE procedure is safe, gives high overall survival and merits phase III investigation for comparison with classical treatment such as doxorubicinlipiodol TACE.

the role of percutaneous Ct guided radiofrequency ablation in intrahepatic recurrence of HCC in patients initially treated with hepatoctomy E. Sotiropoulou, P. Filippousis, M. Seferos, P. Tsagouli, A. Bouga, L. Thanos; Athens/GR purpose: To evaluate the efficacy of radiofrequency ablation (RFA) in patients with intrahepatic recurrence of HCC. material and methods: From December 2003 until December 2007, 41 patients with 56 recurrences of HCC, who were initially treated with partial hepatectomy underwent a total of 75 RFA sessions. The number of lesions ranged between 1 and 3 with a mean size of 2.95 cm. 45 minutes before RFA, 3 mg bromazepan per os and 0.05 gr pethidine hydrochlorique intramusculary were administered. RFA was performed using expandable electrodes. A pulsed RF energy was applied for 12 to 15 min. A dual-phase dynamic contrast enhanced CT was performed after the electrode removal to evaluate the immediate lesion's response to the ablation. Follow up was performed at 1, 3, and 6 months post-RFA and every 6 months afterwards. results: Complete response was seen in 48/56 lesions (85.7%), whereas the rest 8/56 showed partial necrosis and underwent a second RFA. Six patients (14.6%) who presented new lesions within a year, and 5 patients (12.2%) who presented with local tumor progression at the ablated site 6-12 months after the first RFA session, underwent a second RFA as well. Overall survival was 29.61±12.6 months. 1-, 2-, 3-and 4-year survival rate was: 95.12, 73.2, 41.5 and 10%, respectively. Major complications did not occur. Conclusion: RFA of intrahepatic recurrence of HCC post hepatectomy seems to be an efficient treatment modality.

percutaneous radiofrequency ablation of HCC in patients with ascites: can this method be equally efficient? A. Lourbakou, S. Mylona, S. Ntai, E. Daskalaki, G. Karapostolakis, N. Batakis; Athens/GR purpose: To evaluate the contribution of percutaneous radiofrequency ablation (RFA) as treatment of HCC in cirrhotic patients with ascites. material and methods: In a period of seven years, 198 cirrhotic patients (153 men, 35 women, and average age 62.5 y) with HCC (2.4-4.8 cm) proceeded for RFA under CT-guidance. 32/198 had ascites. The re-evaluation after RFA was performed with dual phase CT after I.V. contrast enhancement. Regions with lack of enhancement were characterised as necrotic, and regions with maximum enhancement were estimated as residual disease. In these cases a second RFA session was performed. results: A total necrosis was found in 87.5% of patients with ascites and in 88.6% of patients without ascites (no statistically important difference, p=1.00). In patients with residual disease a second RFA session was performed. No major complications were observed. Patients with ascites had no peritoneal spread in the puncture channel or elsewhere in the abdomen. Conclusion: Percutaneous RFA for treatment of HCC patients with ascites seems to be as safe and efficient as in patients without a ascites.

Chronic Hepatic Venous outflow obstruction: transluminal membranotomy with balloon dilatation. R. Jain 1 , S. Sawhney 1 , S.K. Acharya 2 , P. Sahni 2 ; 1 Muscat/OM, 2 New Delhi/IN purpose: To evaluate effectiveness of percutaneous inferior venacava (IVC) balloon dilatation and stenting in chronic hepatic venous outflow obstruction (HVOO). material and methods: Percutaneous transfemoral endoluminal membranotomy, balloon dilatation, and placement of self-expanding metallic stents in the intrahepatic vena cava were performed in 26 patients with chronic HVOO. results: Two distinct responses were identified depending on type of IVC abnormality: Type I -14 patients -Membranous occlusion of the IVC at the cavoatrial junction by 2.1±.08 mm membrane; one-time puncture and balloon dilatation was curative for all 14 patients-follow-up US up to 2 years demonstrated IVC patency (RRR=1, ARR=1, NNT=1). Type II-12 patients -Steno-occlusive narrowing -41±25 mm long of intrahepatic IVC -balloon dilatation (12/12), metallic stents (8/12) -mean diameter of IVC increased from 2 to 9 mm; cavoatrial pressure gradient dropped from a mean of 16 to 3 mmHg. Of eight patients who had stent placements, seven maintained IVC patency, one died of hepatic venous thrombosis; four patients who did not have stent placement showed recurrent stenosis -repeated balloon dilatations required (average 2.2 per year) to maintain IVC patency (RRR=0.875 (95% CI-0.22, 0.98), ARR=0.875 (95% CI-0.65, 1.1), NNT=1.143 (95% CI-0.9, 1.55)). Conclusion: Type I -Membranous IVC occlusion -membranotomy and balloon dilatation were curative. Type II -Steno-occlusive -did not respond effectively without stent placement; repeated balloon dilatations and/or metallic stents required for maintaining patency.

retrospective study of proximal versus distal main splenic artery embolization P.R. Rau, N.H. Stauffer, A. Denys; Lausanne/CH purpose: Proximal splenic artery embolization (SAE) is supposed to be better tolerated as compared to standard distal or segmental embolization, nevertheless, fulfilling the same treatment objectives. A smaller post-interventional complication rate in terms of infarction and infection is advocated. The objective was to test this hypothesis in our study. epos™ presentatIons B 108 DOI: 10.1007/s10406-008-0008-8 material and methods: 73 consecutive patients undergoing proximal vs. distal or segmental SAE over a time period of 5 years were included in this study. Age, sex, and clinical history leading to SAE were noted. Pre-interventional imaging was reviewed for each patient, and grade of splenic injury and degree of hemoperitoneum were noted. Finally, we checked all digitally available patient records for clinical and radiological follow-up in order to assess post-interventional complications. These were examined on a four point scale, from 0=none, to 3=important complications. results: Complications following proximal SAE (N=11, median=1.0, range=0-2, mean=0.64) did not differ significantly from distal SAE (N=62, median=1.0, range=0-3, mean=0.87), U=303.0, Z=-0.63, p=0.30, r=-0.07. Conclusion: Proximal SAE is a safe and efficacious intervention as compared to distal and segmental SAE. Concerning possible post-interventional complications, there is a slight but non-significant tendency in favour of proximal SAE. There is no elevation of the secondary splenectomy rate in the proximal SAE-group. These results allow us to pursue a prospective study which might reveal a significant advantage in favour of proximal SAE.

percutaneous treatment of two hydatid cysts in the adrenal gland O. Akhan, D. Kaya, B. Ustunsoz, D. Akinci; Ankara/TR purpose: To demonstrate radiological features and evaluate the results of the percutaneous treatment of the hydatid cyst (HC) of the adrenal gland for the first time in the literature. material and methods: Two patients with two HCs of the adrenal gland underwent percutaneous treatment. The first patient was a 72-year old man in which radiological studies disclosed an 8x11x13 cm cystic mass with structures resembling germinative membrane in the left suprarenal region. The second patient was 43-year old female with a 4.5x3.5x3.0 cm cystic mass. The CE 3A HC was considered in the first patient and CE 2 in the second patient according to WHO classification. The interventions were performed under sonographic and fluoroscopic guidance. Among the percutaneous techniques, "catheterization technique with hypertonic saline and alcohol" were chosen for the management. results: No procedure related complications were encountered in the patients. Hospital stay was one day for each patient. A substantial decrease (more than 90%) in the size of the cysts was observed in both patients. No sign of viability was observed during the 45 months for the first and 26 months for the second patient. Conclusion: Percutaneous treatment of adrenal HC is a safe and effective procedure and should be considered as a serious alternative to surgery.

partial splenic embolotherapy S. Karakose, A. Karabacakoglu, S. Yol, E. Ertekin; Konya/TR purpose: The purpose of this study was to evaluate the effectiveness of partial splenic arter embolization in patients with splenomegaly and with or without hypersplenism. material and methods: Thirty-four patients (18 men,14 women, mean age 48, range 34-80) with splenomegaly and thrombocytopenia underwent selective transcatheter splenic arter branches embolization with PVA, microspheres, gelfoam particles and mechanical fibrinated coils. They were not suitable for the surgical splenectomy. Eight of them were refused surgery and for the remaining 24 patients the surgeons had suggested radiological interventional procedures. Transcatheter embolization was applied to the main and distal branches of the splenic artery. In every case, 1 or 2 main branches of the splenic artery were not embolized, since we believe that noninfracted spleen segments may continue to provide immunologic functions. During embolization, super selective catheterization was supplied by micro catheters for the protection of the non-splenic vascular beds. results: After splenic embolization, platet counts had increased in all patients. Fiftynine days after embolization, the portion of infracted spleen tissue was calculated between 40-65% according to CT images. 1 week, 3 months, and 6 months after the procedure, CT and US examinations were performed. There was a significant decrease in the dimensions of the spleens. Our patients required post-procedural analgesics for an average of 2-11 days. No major complication was seen. Conclusion: Selective and partial embolization of splenic arterial branches will provide easy, safe and rapid splenic vascular occlusion as an effective alternative therapy to surgical splenectomy.

standardization of mdCt criteria of patients qualifying for endoscopic treatment of organized pancreatic necrosis and assessment of therapeutic effect J.M. Pienkowska, E. Szurowska, J. Wierzbowski, M.

Studniarek; Gdansk/PL purpose: The therapeutic success of endoscopic treatment of organized pancreatic necrosis depends on the appropriate selection of patients. The aims of this study were the analysis of the MDCT criteria of patients qualifying for endoscopic drainage of pancreatic fluid collection (PFC) and the evaluation of the therapeutic effect. material and methods: 40 patients in the period from 6-8weeks after acute phase of pancreatitis with PFC underwent MDCT. The indications for sterile pancreatic necrosis drainage were: a difficult to relieve abdominal pain, symptoms of delayed stomach emptying, anorexia and body weight loss. Transmural, less frequently percutaneous with simultaneous transpapillary aggressive drainage was applied in all patients. In 35 of patients, multiple drainages (2-5) were positioned and left in place for a period for 7-90 days. MDTC was performed in all patients before and after endoscopic drainage. Topography of PFC, size, number and location of the collections were analyzed. results: The size of detected PFC was 45-115 mm (mean 65 mm), the number was 1-3 (mean 1.8). The best position of the drainages location was determined on the strength of the MDCT. The appropriate criterions of evaluation affected that resolution of fluid collections was achieved in all selected lesions. Recurrence occurred in 6 patients, and four of them underwent repetition of the procedure. Conclusion: MDCT is a useful method for patient selected, therapy planning and monitoring drainage of organized pancreatic necrosis resulted in good therapeutic outcomes. 

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P-098, P-149, P-158, P-296, P-303

P-296, P-303

P-142, P-222

SS 9

P-147, P-181, P-274

P-105

P-105, P-112, P-117

P-061, P-119

P-238, P-239, P-240, P-241

P-121, P-129

P-055, P-288

P-238, P-239, P-240, P-241

P-118, P-148

SS 1.02, SS 6.03

P-078, P-233

P-078, P-118, P-148, P-153, P-224

P-169, P-298

P-025, P-073, P-113

P-021, P-219

P-013, P-055

P-021, P-219, P-245

P-148, P-153

P-209, P-089

P-105

SS 5.05, SS

SS 11.05, SS

SS 1.05, SS

P-057, P-058

SS 1.05, SS

P-035, SS 1.05, SS

P-057, P-058

P-055, P-288

SS 9

P-141, P-256, P-262

P-105, P-112, P-117

P-100

SS 9

P-227 F Faccioli N.: P-089

P-055, P-288

SS 1.05, SS

P-166, P-167

SS 3.03, SS 8.03, SS

P-055, P-288

P-064, P-106, P-107, P-108

P-064, P-106, P-107, P-108

P-011, P-171

SS 5.01, SS 8.05, SS

SS 8.05, SS 9

SS 7.05

SS 6.03

P-051, P-261

P-113

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P-191, P-248

P-036, P-043

SS 2.01, SS 7.05, SS 7.07

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P-105, P-112, P-117

P-238, P-239, P-240, P-241

P-044, P-096, P-103, P-111, P-232, P-253

P-075, P-124, P-228

P-170, P-194

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P-002, P-114

P-042, P-049, P-190, P-269

SS 8.07 m Macari M

SS 3.03, SS 8.03

P-015, P-048, P-081

P-083, P-091, P-151, P-157

SS 1.02, SS 6.03, SS 6.07

SS 3.03

P-186, P-282

P-015, P-048, P-081

P-064, P-106, P-107

SS 6.03, SS

P-092, P-189

P-025, P-073

P-173, P-174

P-025, P-073

P-098, P-149, P-158, P-296

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P-044, P-145, P-228, P-253

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P-037, P-143, P-172

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P-082, P-221

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P-083, P-091, P-151, P-157

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P-002, P-114, P-230

P-002, P-230

P-078, P-153

P-171, P-285

SS 7.05

P-092, P-189

P-037, P-143, P-172

P-019, P-022, P-066, P-071, P-084

P-037, P-143, P-172

P-195, P-197

P-105, P-112

P-238, P-239, P-240, P-241

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Blunt abdominal trauma: Ct findings in patients with solid organ, bowel, mesenteric and diaphragmatic injury B. Graça, F. Cavalheiro, M.F.S. Seco, L. Curvo-Semedo, L. Teixeira, F. Caseiro-Alves; Coimbra/PT Learning objectives: To recognize the CT signs of solid organ, bowel, mesenteric and diaphragmatic injuries from blunt trauma. To differentiate CT findings indicative of significant injury from those indicative of nonsignificant injury. Background: Blunt abdominal trauma (BAT) is a common cause of morbidity and mortality among patients admitted to trauma centers after sustaining multiple traumatic injuries. Although abdominal injuries are often suspected in this setting, clinical diagnosis can be challenging due to the lack of specific physical findings in many patients. CT has been shown to be accurate for the diagnosis of solid organ, bowel, mesenteric and diaphragmatic injuries and is the diagnostic test of choice in the evaluation of patients with BAT. Imaging findings or procedure details: In this exhibit we describe and illustrate: 1. The diagnostic evaluation of the patient with BAT. 2. The CT protocols used to perform optimal examinations. 3. The CT findings in: 3.1 Liver trauma; 3.2 Splenic trauma; 3.3 Pancreaticobiliary Trauma; 3.4 Genitourinary Trauma; 3.5 Bowel injury; 3.6 Mesenteric injury; and 3.7 Diaphragmatic injury. Conclusion: Solid organ, bowel, mesenteric and diaphragmatic injuries from BAT may be significant and require immediate surgery or may be nonsignificant and permit nonsurgical treatment. CT is the diagnostic test of choice in the evaluation of these patients and is instrumental to guide treatment planning.

Value of the mdCt in blunt abdominal trauma M.T. Mallebrera, A. Franco, J. Contreras, O. Benitez, B. Gutierrez; Madrid/ES Learning objectives: To review the radiological aspects of blunt abdominal trauma with particular emphasis on MDCT. This review will provide answers to three basic questions: 1. When to perform a MDCT on a patient who has suffered a blunt abdominal trauma? 2. How to plan and carry out the MDCT? 3. What radiologic findings do we need to be familiar with to provide an accurate radiologic report? Background: The actual trend in diagnostic imaging with respect to blunt abdominal trauma is to achieve a fast and accurate diagnosis of the traumatic lesions. To this end, a thorough knowledge of the indications, technical aspects and imaging findings of each modality is essential. Imaging findings or procedure details: We divide blunt abdominal trauma patients into three categories: A. Hemodynamically unstable patients. B. Hemodynamically stable patients. C. Hemodynamically stable patients with hematuria. To provide an adequate scanning protocol MDCT to evaluate abdominal damage in as little as 2 minutes, providing data about vascular and visceral lesions. To describe and to illustrate the most important radiologic findings (haemoperitoneum, active haemorrhage and major visceral damage) with examples from our own practice. Conclusion: Blunt abdominal trauma is a medical emergency. An extensive knowledge of patient classification, the indications of the imaging modalities and technical protocols, together with a familiarity with the imaging findings can greatly improve the quality and response time of the radiological diagnosis.

Left lower quadrant pain: step-wise approach to evaluate it J. Arora, G.S. Karnati; Bristol/UK Learning objectives: To understand the common and uncommon causes of left lower quadrant abdominal pain. To illustrate the imaging findings (plain X-ray, US, and CT) of the various diseases causing left lower quadrant abdominal pain. To understand the appropriate use and role of different imaging modalities. Background: The left lower quadrant (LLQ) abdominal pain can be a real challenge to the radiologists as unlike right lower quadrant pain its causes are not well understood. The differential diagnosis of left lower quadrant abdominal pain are: sigmoid diverticulitis; leaking abdominal aortic aneurysm; renal colic; epididymitis; incarcerated hernia; bowel obstruction; regional enteritis; paninculitis, psoas abscess; and in rare instances, situs inversus with acute appendicitis. Imaging findings or procedure details: In this exhibit, we demonstrate imaging findings and tailored approach for rapid and reasonable evaluation of Learning objectives: To address the advantages and drawbacks of CT in the study of acute abdominal conditions. To illustrate various diagnoses readily apparent on CT and to show common mimickers. Background: The term "acute abdomen" corresponds to a clinical syndrome characterized by sudden onset of abdominal pain requiring emergency treatment, being nowadays one of the commonest conditions in patients admitted to emergency departments. Prompt diagnosis is essential for minimizing morbidity and mortality, but it can be challenging since clinical-laboratory findings are often non-specific, creating the need for efficient imaging techniques. As a result, CT is being increasingly performed in this setting. Imaging findings or procedure details: Acute conditions will be shown according to a topographic classification of pain (one of four abdominal quadrants, epigastric, generalized or flank pain). For each location, examples of the most common conditions will be illustrated, such as acute cholecystitis (RUQ), pancreatitis (LUQ, epigastrium), diverticulitis (LLQ), appendicitis (RLQ), bowel obstruction, GI perforation and mesenteric ischemia (generalized) or urinary colic (flank), as well as other conditions that need to be taken into account in the differential diagnosis. Conclusion: CT is increasingly being seen as the first-line examination in patients with acute abdomen, lacking the disadvantages of plain films and US and replacing them in a wide spectrum of situations. It has gained the status of "goldstandard" over the last years, particularly after the developments in MDCT.

rectus sheath hematoma: Ct findings B. Acu, B. Sarikaya, U. Bekar, Y. Akturk; Tokat/TR purpose: Rectus sheath hematoma (RSH) is an uncommon cause of acute abdominal pain. It is an accumulation of blood in the sheath of the rectus abdominis secondary to rupture of an epigastric vessel or muscle tear. We present clinical, laboratory and imaging findings accompanying with literature knowledge. material and methods: Between January and July 2007, at ages between 47 and 76, two males and three females of a total five patients with acute abdominal pain and palpable abdominal mass were examined with CT. results: At CT examination, two patients in right rectus muscle, two patients in left rectus muscle and one patient in both rectus muscles were seen compatible with hematoma. All of the patients had abdominal mass and have undergone anticoagulant therapy. All of the patients had anemia and leukocytosis. Four patients were treated conservatively and one was showing clinical recovery after a surgery. Conclusion: RSH is observed frequently by an acute abdominal pain and a palpable mass and mimicking an acute intraabdominal pathology. The most common presenting feature is a painful lower abdominal mass that never crossing the midline. Most important predisposing factor is anticoagulant therapy. At the diagnosis of RSH, CT examination is gold standard. RSH is generally treated conservatively. In conclusion, in old patients with acute abdominal pain, infraumblical mass, anemia and using anticoagulant therapy, rectus sheath hematoma should be kept in mind. A careful evaluation of the medical history and clinical suspicion will help to make an accurate diagnosis and avoid an unnecessary laparotomy. To propose a classification for vascular causes of acute abdominal pain based on "vascular rupture", "vascular occlusion", "diminished flow" and "solid organ ischemia". 3. To present selected cases that illustrate the relevance of image in the clinical management of patients. Background: MDCT angiography is the preferred method for imaging in emergent abdominal vascular conditions. It enables the acquisition of highspatial-resolution volumetric data, including small distal visceral branches, as well the aorta and iliac arteries during a single breath hold. Familiarity with the techniques of image acquisition, contrast dynamics, volumetric data postprocessing and interpretation is as important as exact knowledge of the physiology of the lesions. Imaging findings or procedure details: We present images following this classification proposal: (1) The accuracy of the clinical diagnosis and the added value of US and CT in patients with suspected acute cholecystitis (AC) were investigated. material and methods: Sensitivity, specificity and post-test probability of the clinical diagnosis AC were calculated in consecutive emergency department patients with acute non-traumatic abdominal pain. The accuracy of the clinical triad (direct tenderness RUQ, fever and leucocytosis) was also assessed. Posttest probabilities after US and CT in suspected patients were calculated to investigate the added value on top of clinical assessment. results: Prevalence of AC was 5% (52/1021). AC was the clinical diagnosis in 62 patients and was present in 29, yielding a sensitivity of 56% (95% CI: 42-69%). The clinical triad was 100% sensitive and specific, but present in only 8% of AC. Post-test probability for AC after clinical assessment was 46%, which increased to 88% after a positive US or CT in suspected patients. A negative test result decreased the post-test probability to 16% for US and to 19% for CT. US and CT reduced the 33 false-positive clinical diagnoses to 3 false-positives. Amsterdam/NL, 2 Nieuwegein/NL, 3 Apeldoorn/NL, 4 Utrecht/ NL, 5 Hilversum/NL purpose: At the emergency department (ED) plain radiographs are often used as initial imaging modality in patients with acute abdominal pain (AAP). We evaluated the added value of plain radiographs on top of clinical assessment. material and methods: Patients presenting to the ED with abdominal pain prospectively underwent both supine abdominal and upright chest plain radiographs. The treating physician recorded per patient the most likely diagnoses after clinical assessment and after radiographs. Reference standard was final diagnosis after 6 months follow-up. Sensitivity, specificity and change in primary diagnosis were calculated for diagnoses to be made at radiography as bowelobstruction, perforated viscus, and urinary tract stones. results: 1021 consecutive patients, 566 female, mean age 47, were included. Sensitivity of bowel-obstruction was significant higher after radiographs 74% (95% CI: 0.63-0.84) than after clinical assessment 57% (95% CI: 0.46-0.69) (p<0.01). Primary diagnosis changed in 11 patients from another diagnosis into bowel-obstruction, albeit not significant (p=0.06). Sensitivity of urinary tract stones was higher after radiographs, although not significant, 48% (95% CI: 0.28-0.68) versus 68% (95% CI 0.41-0.79) (p=0.375). Sensitivity of perforated viscus did not change after radiographs 15% (95% CI 0.04-0.40 versus 95% CI: 0.04-0.42) (p=1.00). For urinary tract stones and perforated viscus, primary diagnosis did not change significantly between clinical assessment and radiographs (p=0.375 and p=0.45, respectively). Conclusion: There is no added value of plain radiographs after clinical evaluation of non-selected patients with AAP at the ED, even for bowel-obstruction.

Withdrawn Amsterdam/NL, 2 Hilversum/NL, 3 Nieuwegein/NL purpose: To study the effect of secondary CT usage in females with suspected appendicitis and negative US. material and methods: Consecutive emergency department patients with nontraumatic acute abdominal pain were included. Patients were given a most likely diagnosis based on clinical assessment and underwent abdominal US and CT. The percentage of missed appendicitis and the negative appendectomy rate (false positives (FP)/all positives) were calculated for US usage only and subsequently for US combined with CT in females with an inconclusive or negative US or females with only an inconclusive US. results: We included 1021 patients, (55% female; mean age 47 year (19-94)). Acute appendicitis was clinically suspected in 226 females and was present in 104 (pre-test probability: 46%). CT usage in females with an inconclusive US (85/226=38%) would reduce the percentage of missed appendicitis from 24 (25/104) to 8.7% (9/104) as compared to US only, but increase the negative appendectomy rate from 15.9 (15/94) to 20.8% (25/120). CT in all female patients with a negative US (including inconclusives; 132/226=58%) would further reduce the missed appendicitis percentage to 4.8% (5/104), but increase the negative appendectomy rate to 21.4%. Conclusion: Secondary CT in female patients with suspected appendicitis and a negative or inconclusive US would substantially reduce the percentage of missed appendicitis but would increase the negative appendectomy rate.

the radiological diagnosis of adenomyomatosis of the gallbladder H. Stunell, C.F. Murphy, E. Ward, J.M. O'Brien, T. Geoghegan, W. Torreggiani; Dublin/IE Learning objectives: We describe the diagnosis of gallbladder adenomyomatosis on US, CT and MRI, and correlate the characteristic pathological findings with those first described on cholecystography. Background: Adenomyomatosis is a relatively common abnormality of the gallbladder with a reported incidence of 2.8-5%. It is characterized pathologically by excessive proliferation of the surface epithelium and hypertrophy of the muscularis propria, with invagination of the mucosa into the thickened muscularis, forming characteristic Rokitansky-Aschoff sinuses. Occasionally, focal adenomyomatosis may mimic gallbladder carcinoma, making accurate diagnosis of this as a distinct pathological entity essential. Imaging findings or procedure details: Visualization of the characteristic Rokitansky-Aschoff sinuses on US may be difficult due to factors such as obesity, gallbladder calculi and interruption of the beam by bowel gas and the diagnosis is now made more commonly on cross-sectional imaging. Contrast-enhanced CT in the arterial phase best shows enhancement of the mucosal layer of the gallbladder and therefore, the mucosal outpouching into the thickened muscularis. However, we have found MRI using a heavily T2-weighted HASTE sequence to most accurately depict the characteristic features of adenomyomatosis of the gallbladder and associated biliary tract disease. Conclusion: While CT has been shown to be superior to US and cholecystography, MRI using T2-weighted images has been shown to be the most accurate modality for diagnosing gallbladder adenomyomatosis, with a reported accuracy of over 90%.

patterns of lymphadenopathy in GI malignancies M. Duarte, R. Santos, M. Bispo, J. Alpendre, A. Marques, J. Castaño, Z. Seabra; Lisbon/PT Learning objectives: To illustrate patterns of lymphatic spread from different primary GI malignancies. Background: Different primary malignancies have different lymphatic drainage pathways. Proper assessment of lymphatic spread requires careful evaluation of specific pathways. CT plays a central role in diagnosing, staging, management and follow-up of GI malignancies. It is a non-invasive, available diagnostic tool which also allows determination of the most appropriate approach for nodal sampling and helps in the detection of recurrent disease. Imaging findings or procedure details: The authors make a comprehensive review on pathways for lymphatic spread in GI malignancies including oesophagus, stomach, liver, pancreas, biliary system, small bowel and colon. Schematic representations and CT images illustrate these pathways. TDM criteria for pathologic lymph nodes including location, number, location-related size, morphology, density and patterns of contrast uptake are reviewed. Conclusion: Awareness of preferential pathways of lymphatic drainage from different primary GI malignancies allows better assessment of lymphatic nodes involvement and is a precious aid for accurate staging of malignancies.

pelvic retroperitoneal cystic masses: Ct and pathologic findings D.M. Yang, H.C. Kim; Seoul/KR Learning objectives: 1. To demonstrate the anatomy of pelvic retroperitoneum. 2. To illustrate the CT imaging findings of various types of pelvic retroperitoneal cysts. 3. To evaluate the distinguishing points between many types of retroperitoneal cysts. Background: Pelvic retroperitoneal cystic masses (PRCM), which arise within the retroperitoneal space but outside the major organs of that compartment, are uncommon. However, the widespread use of computed tomography (CT) for evaluating abdominal and retroperitoneal diseases has increased the detection rate of retroperitoneal cystic lesions. CT is an ideal tool for assessment of retroperitoneal disease because it provides discrete sectional images of the organs and retroperitoneal compartments. Differential diagnosis of retroperitoneal cystic masses includes cystic teratoma, epidermoid cyst, tailgut cyst, cystic change of neulilemoma and extraskeletal Ewing's sarcoma, perianal mucinous carcinoma, lymphocele, urinoma, and hematoma. Imaging findings or procedure details: 1. Anatomy of pelvic retroperitoneum 2. Various types of PRCM including cystic teratoma, epidermoid cyst, tailgut cyst, cystic change of neulilemoma and extraskeletal Ewing's sarcoma, perianal mucinous carcinoma, lymphocele, urinoma, and hematoma 3. Distinguishing points between many types of retroperitoneal cysts. Conclusion: 1. There is a substantial overlap of CT findings in various pelvic retroperitoneal cysts. 2. Clinical history and certain details seen at CT assist in making correct diagnosis. 3. Familiarity with the CT features of various PRCM facilities accurate diagnosis.

Heterogenous fat distribution in adrenal nodules: a voxel by voxel analysis of Ct attenuation using chemical shift mrI L. Lanka, K.S. Jhaveri, M.A. Haider; Toronto, ON/CA purpose: Heterogeneity can be seen in adrenal adenomas on CT. Mean attenuation does not account for heterogeneity and histograms can be affected by noise. The purpose of this study was to determine the range of attenuation that can be seen in fat rich versus fat poor adenoma regions using voxel by voxel comparative chemical shift MRI (CSMRI) analysis. material and methods: A single unenhanced CT and CSMRI slice could be coregistered for 23/36 adenomas using ImageJ software allowing for voxel by voxel comparison. Lipid rich voxels were defined as having >25% drop in signal intensity on CSMRI. Five of 23 (22%) adenomas were heterogenous (HetAd) having at least 2% and no more than 98% lipid poor voxels. results: The mean attenuation of HetAd was 12 HU (8-23 HU). The mean attenuation was >10 HU in all lipid poor regions. On a voxel by voxel basis, 15% (520/3548) of voxels were lipid poor. There was a significant correlation between signal drop on CSMRI and CT attenuation (r=-0.632, p<0.001). Mean CT attenuation was significantly higher in lipid poor voxels (27.7 HU vs 10.8 HU, p<0.0001). On an adenoma by adenoma basis, 4 (36/957) to 42% (289/677) of the voxels in each adenoma were lipid poor. Conclusion: True lipid poor regions can occupy sizeable subregions of HetAd. The location of measurement within a nodule could affect the diagnosis of benignity.

abdominal hydatid disease: a pictorial review of unusual findings and pathologic features D. Emlik, D. Kiresi, C. Kadiyoran, S. Gumus, K. Odev; Konya/TR purpose: The aim of this study is to illustrate examples of the diagnostic imaging modalities. We also discuss the main differential diagnosis. material and methods: We illustrate a variety of radiological findings on US, CT and MRI in cases seen in our institution. Typical findings, unusual locations (pancreas, kidney, diaphragm, peritoneum, adnexial and perivesical) and complicated cases (peritoneal seeding, biliary communications) are described. Secondary involvement due to peritoneal seeding may be seen in almost any anatomic location and may cause important problems in the differential diagnosis. results: Hydatid disease was correctly diagnosed by the combination of clinical history, imaging findings and serologic test results. Conclusion: Hydatid disease should be considered in the differential diagnosis in all patients presenting cystic lesions of the abdomen in areas where the disease is endemic.