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Hepatocellular carcinogenesis is usually the result of a muti-step process. It begins with an exposure to various risk factors; followed by the development of a chronic hepatitis and cirrhosis that is a pre-neoplastic step; and finally after the occurrence of an hepatocellular carcinoma (HCC), different molecular events control aggressiveness of the tumors. The aim of this work was to identify in the international context, forces and priorities of the fundamental and translational HCC research.

Hepatocellular carcinoma (HCC) is the most frequent type of primary liver cancer and occurs mainly in patients with cirrhosis. This work aimed at reviewing the main data and trends about HCC epidemiology in France, and about prevention, screening and diagnosis in patients with chronic liver diseases. The six following research topics were considered as priorities: 1) to improve epidemiological knowledge of HCC in France; 2) to clarify the epidemiology of HCC occuring in normal liver and to identify predictive factors; 3) to prevent cancer occurrence in patients with cirrhosis; 4) to improve the knowledge of predictive factors for HCC occurrence in patients with cirrhosis; 5) to improve the diagnostic procedure of nodules below 2 cm in diameter in patients with cirrhosis; 6) to understand functioning of medical networks in order to identify the reasons for late diagnosis and treatment of HCC in patients with cirrhosis.

Tumor angiogenesis induces the proliferation of immature blood vessels that are both heterogeneous and leaky. These characteristics can be demonstrated by measuring the perfusion parameters with MRI. Perfusion MRI is usually performed with in T1-weighted dynamic imaging after bolus injection of an exogenous contrast agent such as gadolinium chelate. The perfusion parameters are obtained by semi-quantitative or quantitative analysis of the enhancement curves in the tumor and the arterial input. Perfusion can also be assessed without injecting a contrast agent using arterial spin labeling techniques, diffusion MRI, or BOLD (blood oxygen level dependent) MRI. However, these latter methods are limited by a low signal-to-noise ratio and problems with quantification. The main indication for perfusion MRI is the assessment of antiangiogenic and antivascular treatments. New possibilities for demonstrating angiogenic blood vessels are being opened by molecular imaging.

Resume La biopsie hepatique est la methode de reference actuelle pour evaluer le degre de fibrose hepatique. Plusieurs methodes non vulnerantes ont ete proposees comme alternatives. Parmi celles-ci, l’elastographie est une nouvelle methode permettant d’evaluer le degre de fibrose hepatique en mesurant l’elasticite du parenchyme. Actuellement, l’elasticite hepatiquea surtout ete mesuree par echographie(FibroScan). Une analyse plus detaillee des proprietes visco-elastiques du foie pourrait etre obtenueau moyen de l’elastographie par resonance magnetique.

We performed a study to determine if colour Doppler findings may help to identify the cause of wall thickening in acute non-diverticular diseases of the colon. The study group included 66 patients admitted to the emergency department with a final diagnosis of infectious colitis (n=23), inflammatory colitis (n=10), ischaemic colitis (n=23) and malignant tumours (n=10). The following ultrasound features were assessed: maximal wall thickness, wall stratification, arterial flow in the colonic wall and arteriolar resistive index. Higher values of wall thickness were observed in malignant tumour (18.2+/-6.2 mm, p

Ischemic bowel disease includes acute and chronic mesenteric ischemia, and colon ischemia. Cross-sectional imaging, and more particularly computed tomography, has an increasing role in the detection of acute and chronic mesenteric ischemia. Vascular obstructions or stenoses and changes in the bowel wall can be observed. Functional information can be added with MRI by using sequences that are sensitive to oxygen saturation in the superior mesenteric vein. Arteriography remains the reference examination in patients with acute mesenteric ischemia.

Quantification of hepatic perfusion parameters greatly contributes to the assessment of liver function. The purpose of this study was to describe and validate the use of dynamic MRI for the noninvasive assessment of hepatic perfusion parameters. The signal from a fast T(1)-weighted spoiled gradient-echo sequence preceded by a nonslice-selective 90 degrees pulse and a spoiler gradient was calibrated in vitro with tubes filled with various gadolinium concentrations. Dynamic images of the liver were obtained after intravenous bolus administration of 0.05 mmol/kg of Gd-DOTA in rabbits with normal liver function. Hepatic, aortic, and portal venous signal intensities were converted to Gd-DOTA concentrations according to the in vitro calibration curve and fitted with a dual-input one-compartmental model. With MRI, hepatic blood flow was 100 +/- 35 mL min(-1) 100 mL(-1), the arterial fraction 24 +/- 11%, the distribution volume 13.0 +/- 3.7%, and the mean transit time 8.9 +/- 4.1 sec. A linear relationship was observed between perfusion values obtained with MRI and with radiolabeled microspheres (r = 0.93 for hepatic blood flow [P < 0.001], r = 0.79 for arterial blood flow [P = 0.01], and r = 0.91 for portal blood flow [P < 0.001]). Our results indicate that hepatic perfusion parameters can be assessed with dynamic MRI and compartmental modeling.

Background Most series that report the results of surgical treatment for congenital liver cysts focus more on the technical aspects of the operation than on the late outcome of these patients. In this paper, we emphasize the importance of appropriate patient selection and adequate surgical technique for successful long-term outcome.

The aim of this study was to analyze the color Doppler sonographic findings in primary epiploic appendagitis. Color Doppler sonographic findings of ten patients with primary epiploic appendagitis were reviewed. The following sonographic features were analyzed: identification of a mass adjacent to the colonic wall; identification of spotty color areas with arterial flow in this mass and detection of abnormalities of the colonic wall adjacent to the infiltrated fatty tissue. A well-delineated hyperechoic mass adjacent to the colonic wall was detected in each patient with sonography. No colonic wall abnormalities were observed nor color Doppler signal in and around the hyperechoic area. Absence of flow at color Doppler sonography is an additional feature of epiploic appendagitis.

BACKGROUND: Transjugular intrahepatic portosystemic shunting (TIPS) has become an effective treatment for the complications of portal hypertension. We assessed the feasibility and outcome of TIPS in liver transplant recipients. METHODS: During the period from December 1992 to January 1998, eight adults presenting recurrent hepatitis C virus (five patients) and hepatitis B virus (one patient) infection, veno-occlusive disease (one patient), and secondary biliary cirrhosis (one patient) had TIPS because of refractory ascites (five patients), bleeding esophageal varices (one patient), refractory hepatic hydrothorax (one patient), retransplantation (two patients), and redo-biliary surgery (one patient). RESULTS: In two patients, the procedure was difficult due to cavo-caval implantation. Ascites, hydrothorax, and variceal bleeding were controlled in all patients. Moderate to severe encephalopathy developed in four patients; two patients had worsening of their existing encephalopathy. Three of five patients treated with cyclosporine needed a drastic dose reduction due to the development of severe side effects. No long-term survivor developed shunt stenosis or occlusion. Two patients did moderately well at 6 and 14 months, respectively; the former died due to chronic rejection while waiting for a retransplantation. Three did well at 14, 36, and 28 months, respectively; the latter patient died of liver failure 32 months after TIPS. One jaundiced patient died after 1.5 months due to necrotic pancreatitis. Two patients died after 4 and 8.5 months, respectively, due to liver failure; the latter was doing well until 7 months after TIPS. CONCLUSIONS: TIPS is feasible in transplant recipients in cases of decompensated allograft cirrhosis, of allograft veno-occlusive disease or when retransplantation or redo-biliary surgery are scheduled in the presence of portal hypertension. At transplantation, the surgeon should keep in mind the eventuality of a later TIPS procedure. Close immunosuppression monitoring is warranted because modified metabolization of cyclosporine (and probably tacrolimus) may cause serious side effects.

Objective: to evaluate the accuracy of colour Doppler sonography (CDS) in the assessment of the left hepatic arterial supply in living donors before hepatic transplantation. Material and methods: Pre-operative sonographic Doppler data of the left hepatic artery (LHA) were compared retrospectively with the selective hepatic angiographic data and the intra-operative observations in 60 living donors. Results: Pre-operative Doppler data of the LHA were available in 53 cases and incomplete or absent in seven cases. In 51 cases (96%) the origin of the LHA or an accessory LHA were correctly described at Doppler sonography (44 classical LHA in anatomic position, seven accessory LHA). In 11 cases (21%), Doppler data were insufficient or incorrect to define the arterial supply of the hepatic segments II, III and IV. Doppler studies were unable to determine the length or the diameter of the LHA. Conclusion: Doppler sonography seems to be able to define the main left hepatic artery anatomy. Selective hepatic angiography is still indicated to determine the length, diameter and intra-hepatic segmental supply.

BACKGROUND: The ultimate goal of surgery for hematological disorders is the complete removal of both the spleen and accessory spleens in order to avoid recurrence of the disease. Whereas splenectomy by open surgery provides excellent results, the validity of laparoscopic splenectomy in this regard remains unknown. OBJECTIVE: The purpose of this study was to evaluate the detection of accessory spleens during laparoscopic splenectomy for hematologic diseases. METHODS: We therefore evaluated the pre-, intra-, and postoperative detection of accessory spleens in a consecutive series of 18 patients treated by elective laparoscopic splenectomy for hematological diseases by using computed tomography (CT) and denatured red blood cell scintigraphy (DRBCS). RESULTS: Preoperative CT, DRBCS, and laparoscopic exploration detected 25%, 25%, and 75% of accessory spleens, respectively. At time of laparoscopy, 16 accessory spleens were detected in seven of the 18 patients (41%). In two patients (11%), laparoscopic exploration failed to detect accessory spleens, whereas preoperative CT (one case) and DRBCS (one case) did reveal them. Postoperatively, during a mean follow-up of 28 months (median, 24; range, 12-44 months), nine patients (50%) showed persistence of splenic tissue by DRBCS, and three of them had signs of disease recurrence. CONCLUSIONS: This prospective clinical study suggests that elective laparoscopic surgery for hematological diseases does not allow complete detection of accessory spleens. Moreover, after such a laparoscopic approach, residual splenic tissue is detectable in half of the patients during the follow-up.

Radiation-induced liver disease is recorded as a form of veno-occlusive disease. Its pathogenesis remains unclear even if the initial injury likely occurs in the endothelial cells of central veins. The aim of our study was to investigate liver morphological features in relation to alpha-isoform of smooth muscle actin expression in hepatic stellate cells in six patients treated by localized radiotherapy on the biliopancreatic area. Within the month after completion of treatment, an activation of hepatic stellate cells strictly confined to irradiated areas and coinciding with congestive changes was observed. At a later stage, collagen deposition gradually increased, replacing the congestive and destroyed areas. This new fibrotic tissue also contained numerous alpha-smooth muscle positive cells. Our data suggest that early hepatic stellate cells activation coinciding with congestive changes plays an important role in radiation liver injury and ensuing fibrosis.

OBJECTIVE: The aim of our prospective study was to compare the values of ferumoxides-enhanced gradient-echo and T2-weighted spin-echo MR imaging for the detection and segmental location of malignant hepatic tumors. SUBJECTS AND METHODS: Eighteen patients underwent ferumoxides-enhanced T2 weighted spin-echo and steady-state gradient-echo imaging before surgery. Intraoperative sonography was used as the reference examination and showed 28 malignant tumors involving 39 of the 144 hepatic segments. The MR images were reviewed independently by two observers who recorded the number of tumors and their segmental location. The results of the segmental location were subjected to receiver-operating-characteristic analysis. Tumor-liver, vessel-liver, and tumor-vessel contrast-to-noise ratios were calculated. RESULTS: Detection on the gradient-echo images did not differ significantly from that on the T2-weighted spin-echo MR images (observers A and B detected 23 and 24 tumors, respectively, on the gradient-echo images; the two observers each detected 22 tumors on the T2-weighted spin-echo images). Segmental localization was significantly better on the gradient-echo images than on the T2-weighted spin-echo images (mean area under the receiver-operating-characteristic curve: 0.974 versus 0.895 for observer A and 0.962 versus 0.906 for observer B, p = .024). The highest contrast-to-noise ratios for vessel to liver and tumor to vessel were obtained on the gradient-echo images and the highest tumor-liver contrast-to-noise ratio was obtained on the T2-weighted spin-echo images. CONCLUSION: In our study, ferumoxides-enhanced gradient-echo imaging was as accurate as T2-weighted spin-echo imaging for revealing malignant hepatic tumors and was superior for showing their segmental location.

The purpose of this study was to determine the prevalence of enlargement of the azygos system in the case of lung sequestration and its potential usefulness in the differential diagnosis of lower lobe opacities. Seven consecutive adult cases of pulmonary sequestrations were retrospectively enrolled; 4 sequestrations were proved surgically and all 7 angiographically. A group of 50 consecutive patients with a normal chest CT were used as controls. Another group consisted of 25 consecutive patients identified on the basis of an opacity in a posterobasal location on chest CT. For the 3 groups, the maximum diameter of the azygos and hemiazygos veins was measured, the level of measurement located between the upper poles of the kidneys and the confluence of inferior pulmonary veins into the left atrium. The diameter of the azygos veins (mean 10.4 +/- 5.1 mm) and of the hemiazygos veins (mean 7.1 +/- 3.0 mm) in the sequestration group was significantly larger than the diameter of the azygos and hemiazygos veins in the control group (mean 5.7 +/- 2.5 mm, and 3.4 +/- 2.4 mm, respectively), as well as in the study group (mean 5.9 +/- 2.6 mm and 3.3 +/- 2.6 mm, respectively). Our results suggest that enlargement of the azygos system in association with a posterobasal chest opacity, although nonspecific, may be a useful additional CT sign of sequestration.

The classical method for31P NMR determination of intracellular free magnesium concentration ([Mg free 2+ ]) requires an accurate knowledge of the apparent dissociation constant (K D ) of MgATP. There is a large difference between the previously determined values ofK D . Although the value of 50 µM, determined by a31P NMR method, is now largely accepted, a value of 86 µM has more recently been measured with a fitting method derived from the original one, and with a different ionic strength. The purpose of our study was to assess if the cause of the difference between these two previously reportedK D values was due to the measuring method or to the ionic strength value used.

OBJECTIVE: The purpose of this study was to determine the feasibility of using three-dimensional spiral CT after IV administration of a cholangiographic agent for noninvasive detection of anatomic variations of the bile ducts and common bile duct stones before or after laparoscopic cholecystectomy. SUBJECTS AND METHODS: Three-dimensional spiral CT cholangiography was performed before laparoscopic cholecystectomy in 24 patients and after surgery in two patients who had recurrent symptoms. After slow infusion of 250 ml of iodipamide, spiral CT was performed. Three-dimensional images of the bile ducts and a secondary reformation through the long axis of the common bile duct were obtained. Visualization of the biliary tract was evaluated by two observers. Detection of anatomic variations and common bile duct stones was assessed in 19 patients for whom a gold standard (operative or retrograde cholangiogram) was available. RESULTS: In all 26 patients, the common bile duct and the confluence of the hepatic ducts were seen on three-dimensional spiral CT cholangiograms, and in 21 patients second- or higher-order branches were also seen. Seven patients had anatomic variations and two had common bile duct stones. These anomalies were proved by operative cholangiography in each case, except for a low junction of the cystic duct and a common bile duct stone, which were shown by retrograde cholangiography. Six of the seven anatomic variations were adequately detected with spiral CT cholangiography, as were the two cases of common bile duct stones. CONCLUSION: Three-dimensional spiral CT cholangiography is a feasible method for noninvasive detection of biliary anatomic variations and common bile duct stones before or after laparoscopic cholecystectomy.

The diagnosis of saber-sheath trachea is easy at CT due to its cross-sectional imaging, but the significance of this CT sign has not been evaluated in the diagnosis of chronic obstructive pulmonary disease (COPD). Various signs of COPD were compared between a series of 20 patients with a saber-sheath trachea at CT (tracheal index ≤ 66%) and a group of 20 pneumologic control patients without saber-sheath trachea (tracheal index ≥ 70%). These signs included clinical and standard radiographic indices of COPD, sternum-spine distance and 3 functional tests of COPD: forced expiratory volume in one second, carbon monoxide diffusing lung capacity, and functional residual capacity (FRC). A significant difference was found between the 2 groups, concerning the values of FRC (p

Objective: Our retrospective study was performed to reassess the common dynamic CT manifestations of cystic tumors of the pancreas and to determine whether they might allow the differentiation between benign and malignant tumors. Materials and Methods: Dynamic CT examinations of 19 patients with 20 cystic tumors of the pancreas, including 7 serous cystadenomas, 3 benign mucinous cystadenomas, 5 mucinous cystadenocarcinomas, 3 mucin-producing duct ectasias, and 2 papillary cystic epithelial neoplasms, were retrospectively reviewed. The examinations were obtained with 4 to 5 mm collimation with intravenous injection of 120-130 ml of contrast agent. Results: Calcifications were found only in benign tumors (seven serous cystadenomas). Internal septations were found in benign and malignant tumors (seven serous cystadenomas, three benign mucinous cystadenomas, three mucinous cystadenocarcinomas). Solid excrescences within cystic cavities were found only in malignant tumors (two mucinous cystadenocarcinomas, two mucin-producing duct ectasias). Dynamic CT features allowed the distinguishing of serous cystadenomas from other cystic tumors and mucin-producing duct ectasias from other mucinous tumors. Dynamic CT features did not permit differentiation between benign mucinous cystadenomas, mucinous cystadenocarcinomas, and papillary cystic epithelial neoplasms. Conclusion: The review suggests that dynamic CT findings are useful to differentiate (a) serous cystadenomas and mucin-producing duct ectasias from other cystic tumors of the pancreas and (b) benign from malignant tumors. Such differentiation has impact on patient management.

The sonographic studies of 72 patients with pathologically proven Hodgkin's or non-Hodgkin's hepatic lymphoma were retrospectively reviewed. Sixty-eight patients (94%) had secondary hepatic lymphoma (nine of them had AIDS-related lymphoma) and four patients (6%) had primary lymphoma of the liver. Forty-six of 72 patients (64%) had diffuse hepatic involvement, and 26 of 72 patients (36%) had focal liver lesions as demonstrated by sonography. Four patterns of disease were identified: (a) hepatomegaly was depicted by sonography in 26 of the 59 patients with secondary hepatic lymphoma not related to AIDS, in two of the nine patients with AIDS-related secondary hepatic lymphoma, and in one of the four patients with primary hepatic lymphoma; (b) multiple rounded well-delineated hypoechoic liver lesions were found in 22 of the 68 patients with secondary hepatic lymphoma; (c) a large heterogeneous echoic mass, which was an evocating clue to the diagnosis of primary lymphoma of the liver, was found in the four patients with primary lymphoma of the liver; and (d) an absence of sonographic abnormalities was found in 20 of the 59 patients with secondary lymphoma not related to AIDS. Liver involvement with lymphoma should be considered in any patient who develops multiple homogeneous hypoechoic liver masses, even in the absence of known underlying lymphomatous disease.

To evaluate the accuracy of surface coil gradient-echo (GRE) imaging in the detection of regenerative nodules of hepatic cirrhosis, 53 patients with diffuse liver disease, among whom 31 had cirrhosis, were prospectively investigated. Three GRE sequences acquired with a surface coil were used in the study: a T2*-weighted, a T1-weighted, and a gadopentetate-enhanced sequence. ROC analysis showed that two surface coil GRE sequences were superior to conventional T2-weighted spin-echo imaging acquired with a body coil for the detection of regenerative nodules. The detection of regenerative nodules was also more accurate for the diagnosis of cirrhosis than the measurement of the caudate-to-right lobe ratio. These results suggest that there could be a potential for surface coil GRE imaging in the assessment of the characteristic macroscopic alterations of cirrhosis.

We report a case of angiomyolipoma of the liver with emphasis on the appearance at MRI after administration of ferumoxides. Post-contrast T1- and T2-weighted images showed a frank decrease of signal intensity in a rim on the margin of the tumor. This unusual finding was related to the presence of an increased number of CD68-positive histiocytic cells in the periphery of the lesion and in the adjacent liver parenchyma.

The reference method for detecting and quantifying hepatic steatosis and fibrosis is the histopathological analysis of liver biopsies. Studies performed in animals and humans have shown that magnetic resonance imaging (MRI) is useful for the accurate and non-invasive quantification of these lesions. For fibrosis quantification, functional MRI methods have to be used, including perfusion MRI, diffusion MRI, and more particularly MR elastography. Modifications of the visco-elastic parameters of the liver can also be observed with MR elastography in hepatic diseases without fibrosis, such as the early stages ofnon-alcoholi steatohepatitis. Finally, accurate quantification of liver steatosis can be performed by observing the difference of resonance frequencies between the protons of fat and water at spectroscopy or chemical shift MRI. In conclusion, combined quantification of liver steatosis and fibrosis can be performed with MRI.

Hepatocellular carcinogenesis is usually the result of a muti-step process. It begins with an exposure to various risk factors; followed by the development of a chronic hepatitis and cirrhosis that is a pre-neoplastic step; and finally after the occurrence of an hepatocellular carcinoma (HCC), different molecular events control aggressiveness of the tumors. The aim of this work was to identify in the international context, forces and priorities of the fundamental and translational HCC research.

Hepatocellular carcinoma (HCC) is the most frequent type of primary liver cancer and occurs mainly in patients with cirrhosis. This work aimed at reviewing the main data and trends about HCC epidemiology in France, and about prevention, screening and diagnosis in patients with chronic liver diseases. The six following research topics were considered as priorities: 1) to improve epidemiological knowledge of HCC in France; 2) to clarify the epidemiology of HCC occuring in normal liver and to identify predictive factors; 3) to prevent cancer occurrence in patients with cirrhosis; 4) to improve the knowledge of predictive factors for HCC occurrence in patients with cirrhosis; 5) to improve the diagnostic procedure of nodules below 2 cm in diameter in patients with cirrhosis; 6) to understand functioning of medical networks in order to identify the reasons for late diagnosis and treatment of HCC in patients with cirrhosis.

The image analysis and kinetic modeling methods used in dynamic contrast-enhanced magnetic resonance imaging of the kidney are reviewed. Image analysis includes various techniques of coregistration and segmentation. Few methods have been completely implemented. Nevertheless, the use of coregistration may become a standard to decrease the effect of motion on abdominal images and improve the quality of the renal signals. Kinetic models are classified into three categories: enhancement-based, external and internal representations. Enhancement-based representations are limited to a basic analysis of the tracer concentration curves in the kidneys. Their relationship to the underlying physiology is complex and undefined. However, they can be used to evaluate the split renal function. External representations assess the kidney input and output. An external representation based on the up-slope of the renal enhancement to calculate the renal perfusion is commonly used because of its simplicity. In contrast, external representation based on deconvolution or identification methods remain underexploited. For glomerular filtration, an internal representation based on a two-compartmental model is mostly used. Internal representations based on multi-compartmental models describe the renal function in a more realistic way. Because of their numerical complexity, these models remain rarely used.

The aim of this study was to assess the importance of deconvolution for the calculation of renal perfusion and glomerular filtration rate (GFR) on the basis of concentration-time curves as measured with perfusion MRI. Six rabbits were scanned dynamically after injection of a gadolinium chelate. Concentration-time curves were generated by manually drawing regions of interest in the aorta and the renal cortex. To remove the dependency on the arterial input function, a regularized structured total least-squares deconvolution algorithm was used to calculate the renal impulse response. This curve was fitted by the sum of two gamma variate functions, corresponding to the passage of the contrast agent in the glomeruli and the proximal convoluted tubules. Tracer kinetics models were applied to these two functions to obtain the renal perfusion and GFR. For comparison, these two parameters were also calculated on the basis of the renal concentration-time curve before deconvolution. The renal perfusion values correlated well (r = 0.9, P = 0.014) with the values calculated by a validated upslope method. The GFR values correlated well (r = 0.9, P = 0.014) with the values obtained from the clearance of (51)Cr-EDTA. A comparison of the values obtained with and without deconvolution demonstrated the necessity of deconvolution.

BACKGROUND AND STUDY AIMS: The aim of this study was to compare prospectively the diagnostic efficacy of magnetic resonance (MR) imaging and endoscopic ultrasonography (EUS) in extrahepatic biliary obstruction. PATIENTS AND METHODS: A total of 50 patients with suspected benign or malignant extrahepatic biliary obstruction underwent MR imaging, including MR cholangiopancreatography, and EUS, within a median time delay of 1 day. The final diagnosis was established by endoscopic retrograde cholangiopancreatography in 37 cases, intraoperative cholangiography in nine cases, and clinical and biochemical follow-up in four cases. RESULTS: In total, 33 patients had extrahepatic biliary obstruction, of benign origin in 21 cases and of malignant origin in 12 cases, whereas 17 had no evidence of obstruction. The sensitivity and specificity of MR imaging were 91% and 94 %, respectively. There were one false-positive and three false-negative results, all related to choledochal sludge. The corresponding values for EUS were 97% and 88%. There were two false-positive results and one false-negative result. False-positive diagnoses were related to the presumed presence of biliary sludge and choledocholithiasis, whereas the false-negative diagnosis occurred in one patient with a final diagnosis of sludge. No significant difference in sensitivity and specificity was observed between the two imaging methods (P>0.05). CONCLUSION: In our study MR imaging was as accurate as EUS in the diagnosis of extrahepatic biliary obstruction.

To evaluate the impact of standardized operative and peri-operative care on the outcome of liver transplantation in a single center series of 395 adult patients.Between February 1984 and December 31, 1998, 451 orthotopic liver transplantations were performed in 395 adult patients (or = 15 years) at the University Hospitals St-Luc in Brussels. Morbidity and mortality of the periods 1984-1990 (Gr I--174 pat.) and 1991-1998 were compared (Gr II--221 pat.). During the second period anti-infectious chemotherapy and perioperative care were standardized and surgical technique changed from classical orthotopic liver transplantation with recipients' vena cava resection (and use of veno-venous bypass) towards liver implantation with preservation of the vena cava (without use of bypass). Immunosuppression was cyclosporine based from 1984 up to 1996 and tacrolimus based during the years 1997 and 1998. Immunosuppression was alleviated during the second period due to change from quadruple to triple and even double therapy and due to the introduction of low steroid dosing and of steroid withdrawal, once stable graft function was obtained. Indications for liver grafting were chronic liver disease (284 pat--71.9%), hepatobiliary tumor (52 pat--13.2%), acute liver failure (40 pat--10.1%) and metabolic disease (19 pat--4.8%). Regrafting was necessary because of graft dysfunction (21 pat), technical failure (12 pat), immunological failure (18 pat) and recurrent viral allograft disease (5 pat); three of these patients were regrafted at another institution. Follow-up was complete for all patients with a minimum of 9 months.Actuarial 1, 5 and 10 years survival rates for the whole group were 77.9%, 65.7% and 58.3%. These survival rates were respectively 77.3%, 69.7%, 62.5% and 73.2%, 59.6% 51.4% for benign chronic liver disease and acute liver failure; those for malignant liver disease were 80.6%, 44.3% and 36.7%. Early (3 months) and late (3 months) posttransplant mortalities were. 14.4% (57 pat) and 21.2% (84 pat). Early mortality lowered from 20% in Gr I to 9.4% in Gr II (p0.02); this was due to a significant reduction during the second period of bacterial (99/174 pat.--56.9% vs 82/221 pat.--37.1%), fungal (14 pat.--8% vs 7 pat.--3.2%) and viral (87 pat.--50% vs 49 pat.--22.2%) infections (p0.05) as well as of perioperative bleeding (92 pat.--52.9% vs 39 pat.--17.6%--p0.001). Late mortality remained almost identical throughout the two periods as lethal outcome was mainly caused by recurrent allograft diseases, cardiovascular and tumor problems. Morbidity in these series was important considering that almost, half of the patients had a technical complication, mostly related to bleeding (131 pat--33.2%) and biliary problems (66 pat--16.7%). Retransplantation index was 1.1 (54 pat.--14%). Early retransplantation mortality was 24%; it lowered, although not yet significantly, during the second period (8/25 pat.--32% vs. 5/29 pat.--17.2%).Despite a marked improvement of results, liver transplantation remains a major medical and surgical undertaking. Standardization of operative and perioperative care, less haemorraghic surgery and less aggressive immunosuppression are the keys for further improvement.

Background: Gallbladder duplication is a rare congenital condition, which can now be detected preoperatively by imaging studies. Methods: We report a case of duplicated gallbladder with symptomatic unilobar gallstones. Appropriate biliary workup (ultrasound, oral cholecystography, and intravenous cholangiography) allowed a correct preoperative diagnosis. Results: Laparoscopic treatment included selective removal of the diseased accessory gallbladder. However, postoperative acute cholecystitis and symptomatic gallstone occurred in the remaining main gallbladder, and laparoscopic reintervention was required 27 months later. Conclusions: This case illustrates the need for complete removal of both gallbladders during initial surgery. Precise intraoperative recognition of vascular and biliary anatomy-including abnormalities-is highlighted to avoid mistakes during surgery.

To prospectively compare the diagnostic accuracy of computed tomography (CT) during arterial portography (CTAP) with that of unenhanced and ferumoxides-enhanced magnetic resonance (MR) imaging at 0.5 T in the detection of hepatic metastases.Four pairs of radiologists independently assessed the metastatic involvement of 134 hepatic segments (31 with and 103 without metastasis) in 17 patients at unenhanced and ferumoxides-enhanced spin-echo and gradient-echo MR imaging (alone and in combination) and at CTAP. The diagnostic performance of the various imaging modalities was assessed by means of receiver operating characteristic analysis.The accuracy of CTAP, unenhanced MR imaging (combined unenhanced sequences), and ferumoxides-enhanced MR imaging (combined contrast material-enhanced sequences) was 0.925, 0.908, and 0.951, respectively. Ferumoxides-enhanced MR imaging was significantly more accurate (P.05) than unenhanced MR imaging and CTAP. When 14 segments containing cysts were excluded, the difference between ferumoxides-enhanced MR imaging and CTAP was no longer statistically significant (P = .1).Ferumoxides-enhanced MR imaging is more accurate than unenhanced MR imaging and at least as accurate as CTAP for the detection of hepatic metastases.

The purpose of this study was to correlate the MRI features of the anal canal with histologic findings. T1- and T2-weighted MR images of nine anal canals were obtained after fixation in 10% formalin. In three specimens, imaging was repeated after removal of histologic layers with a dissecting microscope. Corresponding histologic slices were stained with hematoxylin-eosin, Masson trichrome, and periodic acid-Schiff. Four layers were visualized on T2-weighted images. An inner layer of high signal intensity and a second layer of low signal intensity corresponded to the mucosa as well as mucous secretions and to the submucosa. The high signal intensity layer vanished at the distal part of the anal canal in accordance with the lack of mucus-secreting epithelium below the level of the dentate line. A third layer of intermediate signal intensity corresponded to the internal sphincter. A fourth layer of low signal intensity corresponded to the longitudinal muscle and external sphincter. T2-weighted MRI is capable of showing the internal architecture of the wall of the anal canal. In particular, the internal sphincter can be differentiated from the external sphincter and longitudinal muscle.

The natural history of pseudoaneurysms complicating pancreatitis is unknown. A patient with chronic pancreatitis is described in whom thrombosis of a splenic artery pseudoaneurysm occurred. Early diagnosis and radical treatment of a bleeding pseudoaneurysm are mandatory. When elective treatment is considered, however, contrast enhanced computed tomography may be useful just before surgery as thrombosis may occur.

To evaluate the accuracy of surface coil gradient-echo (GRE) imaging in the detection of regenerative nodules of hepatic cirrhosis, 53 patients with diffuse liver disease, among whom 31 had cirrhosis, were prospectively investigated. Three GRE sequences acquired with a surface coil were used in the study: a T2*-weighted, a T1-weighted, and a gadopentetate-enhanced sequence. ROC analysis showed that two surface coil GRE sequences were superior to conventional T2-weighted spin-echo imaging acquired with a body coil for the detection of regenerative nodules. The detection of regenerative nodules was also more accurate for the diagnosis of cirrhosis than the measurement of the caudate-to-right lobe ratio. These results suggest that there could be a potential for surface coil GRE imaging in the assessment of the characteristic macroscopic alterations of cirrhosis.

Extracorporeal shock wave lithotripsy of gallstones is a safe and well-tolerated procedure. Patients are now treated without general anesthesia and, increasingly, on an outpatient basis. Skin petechiae and transient hematuria are the most common side effects. Episodes of biliary colic are common in the follow-up period, but more serious adverse side effects such as cholecystitis and pancreatitis are distinctly uncommon. It is estimated that only 15% to 20% of all patients with symptomatic cholelithiasis are suitable lithotripsy candidates. As our knowledge of the procedure grows, it seems clear that the best results are obtained in patients with solitary radiolucent stones less than or equal to 20 mm, with stone-free rates at 12 months above 80%, for this selected group of patients. Adjuvant oral bile-acid dissolution therapy should be used in conjunction with gallstone lithotripsy. Gallstone recurrence remains to be established by clinical studies. Therapy for gallstones in 1991 has to be reevaluated by an interdisciplinary approach, taking into account not only open cholecystectomy, but also other modalities such as medical dissolution, laparoscopic surgery, percutaneous cholecystolithotomy and extra-corporeal shock wave lithotripsy. The appeal of the laparoscopic approach will substantially reduce the pool of patients for lithotripsy. Nevertheless, lithotripsy will continue to be a viable treatment option for patients with a single radiolucent stone. It is an outpatient procedure and doesn't require any incision or general anesthesia.

Objectifs Connaitre les particularites de la diffusion hepatique. Savoir realiser les sequences de diffusion hepatique. Connaitre l’interet de la diffusion dans les pathologies diffuses et en detection et caracterisation de lesions focales. Messages a retenir Les sequences de diffusion font partie du protocole d’acquisition des lesions focales du foie en IRM. Les protocoles d’acquisition dependent des questions cliniques : detection ou caracterisation. La detection des tumeurs hepatiques est accrue par les sequences de diffusion. Resume Le foie est un organe isotropique. Il est souhaitable de faire une sequence a multiples valeurs de b. La valeur maximale du b est comprise entre 500 et 1000. On privilegie les sequences sans synchronisation respiratoire. Le coefficient d’ADC diminue avec la fibrose hepatique. Les tumeurs hepatiques benignes ont un ADC plus eleve que les tumeurs hepatiques malignes. Les sequences de diffusion sont aussi utiles pour la detection de lesions hepatiques notamment lors de la recherche de metastases hepatiques.

The anatomic relationship between the popliteal artery and vein means that an arteriovenous fistula can be created when a popliteal artery approach is used for endovascular interventions. To determine the best site for retrograde puncture of the popliteal artery, we studied six cadaveric specimens, CT scans of 31 patients at 280 levels, and 30 plain radiographs of the knee. In the cadaveric specimens, the vessels were enclosed in a common sheath. In 92% of all levels studied on CT, the artery was anterior to the vein (anterolateral in 9%, anteromedial in 43%, strictly anterior in 40%), and more than 25% of the diameter of the artery overlapped the vein in 87% of these levels. However, at the most cranial level analyzed (64 mm above the femorotibial joint space level), such an overlap occurred in only 60%, and the artery was medial in 25%, resulting in a relationship between the artery and the vein that involved less risk of fistula. On radiographic study, the popliteal crease was located above the level of the joint space (considered the most reliable landmark of the popliteal fossa anatomy) in 97% of cases, although the values were scattered (mean, 2.9 +/- 1.5 cm). In order to minimize the risk of creating an arteriovenous fistula, we recommend a skin incision be located 3-4 cm above the joint level as determined by fluoroscopy, and a puncture directed obliquely from caudal to cranial and from medial to lateral.

Objectifs Comparer prospectivement les performances de l’elastographie par resonance magnetique (ERM) avec les sequences echo de spin (ES) et echo planar (EP) pour l’evaluation de la fibrose hepatique. Materiels et methodes Vingt-quatre patients consecutifs ont eu une biopsie hepatique pour suspicion d’hepatopathie chronique. L’ERM a ete realisee avec les sequences ES et EP. Le degre de fibrose histologique a ete determine avec le score METAVIR. Resultats Les temps d’examen etaient d’environ 20 minutes en ES, et de 2 minutes en EP. Les rapports signal sur bruit etaient : ES, 34,10 ± 8,14 ; EP, 31,85 ± 7,22 (p = 0,33). Le coefficient de correlation entre les mesures d’elasticite en ES et EP etait : r = 0,83 (p Conclusion Ces resultats suggerent que l’ERM en EP peut etre realisee rapidement tout en donnant des resultats similaires au SE pour l’evaluation de la fibrose hepatique.

Objectifs Decrire les principes de l’elastographie par IRM. Comprendre la place de l’elastographie par IRM dans la detection et de la gradation de la fibrose hepatique. Apprendre le role emergent de l’elastographie par IRM dans la caracterisation des tumeurs hepatiques. Points cles L’elastographie par IRM permet de determiner l’elasticite et la viscosite d’un tissu en etudiant la propagation d’ondes mecaniques a basse frequence. Il s’agit d’une methode sensible et specifique pour detecter la fibrose hepatique et determiner sa severite. Une augmentation d’elasticite et de viscosite peut etre detectee a un stade precoce de steatohepatite non alcoolique, avant l’apparition d’une fibrose. L’elastographie par IRM permet d’evaluer les proprietes biomecaniques des tumeurs hepatiques et aide ainsi a la caracterisation tumorale. Resume L’elastographie par IRM permet de determiner les proprietes visco-elastiques des tissus en etudiant la propagation d’ondes mecaniques de basse frequence. Dans le foie, ces mesures sont utiles pour evaluer la fibrose et les tumeurs. Ainsi, il a ete montre que l’ elastographie par IRM etait une methode sensible et specifique pour detecter la fibrose hepatique et determiner sa severite. Des etudes preliminaires montrent que l’elastographie par IRM est egalement utile dans la detection precoce de la steatohepatite non-alcoolique et la caracterisation des tumeurs hepatiques malignes primitives et secondaires. L’elastographie par IRM est une methode emergente d’imagerie apportant des renseignements complementaires a l’IRM anatomique et a l’IRM de perfusion et de diffusion dans le foie.

A 57-year-old man was referred to our hospital for evaluation of a 4 cm intrathoracic peripheral mass found incidentally on a routine chest radiograph. The patient, a heavy smoker, had no history of cough, hemoptysis or respiratory tract infection. On admission, physical examination and routine blood tests were unremarkable. A postero-anterior chest radiograph (Fig. 1), a lateral chest radiograph (not shown) and a right anterior oblique view (Fig. 2) were obtained.