肝硬化门静脉性胆病的影像表现

目的：探讨肝硬化门静脉高压性胆病（PB）的MSCT及MRI表现。方法：回顾性分析16例肝硬化PB患者的MSCT及MRI表现,分析门静脉血栓导致PB的解剖位置和临床表现。结果：16例患者中门静脉海绵样变13例,其中8例合并门静脉血栓;门静脉和／或门静脉分支血栓3例。16例患者中3例表现为肝内胆管扩张,9例表现为肝外胆管及一侧肝内胆管扩张,4例表现为肝外胆管和两侧肝内胆管扩张。本组病例门静脉系统侧支循环的类型包括食道一胃底静脉曲张13例（13／16,81％）、胰腺周围静脉曲张10例（10／16,63％）和胆囊静脉曲张10例（10／16,63%）。结论：肝硬化门静脉高压患者出现肝外或肝内胆管扩张时应考虑门静脉高压性胆病的可能。     

Functional causes of the ductal obstructive pattern on hepatobiliary scans

Hepatobiliary imaging with Tc-99m IDA derivatives has proven value for evaluation of biliary disease. Prompt hepatocellular uptake with persistent nonvisualization of the common bile duct and bowel is usually indicative of a high-grade common bile duct obstruction, but is not pathognomonic. A functional abnormality due to hepatocyte dysfunction resulting in intrahepatic cholestasis can also cause this pattern. Two cases of hepatocellular excretory dysfunction, one due to E. coli endotoxemia with intrahepatic cholestasis and the other due to acute hepatitis A that produces ductal obstructive patterns on Tc-99m disofenin scintigraphy in patients with documented patent biliary ducts, are reported. Transhepatic cholangiography or endoscopic retrograde cholangiography may be useful when the diagnosis of biliary ductal obstruction is in doubt.     

Cholangiopathy in extrahepatic portal venous obstruction. Radiological appearances

PURPOSE: To evaluate cholangiographic abnormalities resulting from extrahepatic portal venous obstruction (EHPVO) by sonography and endoscopic retrograde cholangiopancreaticography (ERCP). MATERIAL AND METHODS: Forty-three patients with an established diagnosis of EHPVO were subjected to duplex Doppler sonography and ERCP. Of these, 8 patients had obstructive jaundice. RESULTS: Dilated common bile duct with pericholedochal varices showing a continuous type of flow pattern was seen in 5 EHPVO patients with obstructive jaundice. ERCP revealed cholangiographic abnormalities in 40 patients (93%). Extrahepatic bile ducts were involved in 100% of cases compared to intrahepatic bile ducts (57%). Abnormalities noted were contour irregularity with indentations, displacement and angulation, strictures and filling defects in the extrahepatic ductal system. Intrahepatic bile ducts showed dilatation with areas of narrowing and filling defects. CONCLUSION: Cholangiographic abnormalities are very common in patients with EHPVO, even without clinical manifestations of biliary disease. Extrahepatic bile ducts are far more often involved compared to intrahepatic bile ducts. Extrinsic compression with contour irregularity is the most common cholangiographic finding. Sonographic findings are not diagnostic. Dilated common bile duct with pericholedochal varices was seen in only 5 patients.     

Value of magnetic resonance cholangiography in benign and malignant biliary stenosis: comparative study with direct cholangiography

PURPOSE: Magnetic resonance cholangiography (MRC) is currently under investigation for imaging of biliary stenosis. The purpose of this study was to evaluate the diagnostic value of MRC compared with direct cholangiography in biliary duct diseases, with the exception of biliary-enteric anastomosis. METHOD: Forty-nine patients (26 men, 23 women; median age 60 years) with clinically suspected bile duct stenosis were prospectively included. Magnetic resonance cholangiography was performed within 7 days before direct cholangiography, considered to be the gold standard. Stenosis location, extension, and type according to Bismuth classification as well as diagnostic presumed causes were determined by 2 radiologists and 1 endoscopist. RESULTS: Magnetic resonance cholangiography correctly identified the level of biliary ductal obstruction compared with direct cholangiography findings in 96% patients. Excellent agreement between MRC and direct cholangiography was found for the stenosis location (kappa value, 0.89). Sensitivity and specificity of MRC to detect common bile duct stenosis were 88% and 100%, respectively. Sensitivity and specificity of MRC to detect biliary confluence stenosis were 96% and 93%, respectively. Precise location of the lesion according to Bismuth classification was correctly evaluated on MRC in 74% of patients (kappa value, 0.64). The overall interobserver concordance between radiologists for the level of stenosis was good (kappa value, 0.625). In 35 patients with intrahepatic bile ducts dilation identified on direct cholangiography, 97% of patients were identified on MRC. Moderate concordance between MRC and direct cholangiography was confirmed in the evaluation of the surgical management (kappa value, 0.55). CONCLUSION: Magnetic resonance cholangiography is able to replace diagnostic direct cholangiography to restrict the use of invasive procedures to cases in which therapeutic procedures are anticipated or MRC findings are equivocal, especially in biliary tract diseases.     

Role of MR cholangiopancreatography in patients with failed or inadequate ERCP

OBJECTIVE: The purpose of this study was to evaluate the spectrum of MR imaging features of primary sclerosing cholangitis. MATERIALS AND METHODS: A retrospective review was performed of MR imaging findings including MR cholangiography and multiphasic contrast-enhanced dynamic sequences in 22 patients with primary sclerosing cholangitis. MR imaging analysis included abnormalities of intra- and extrahepatic bile ducts, abnormalities of liver parenchyma, changes in liver morphology, and lymphadenopathy. RESULTS: Abnormal findings of bile ducts were seen in all 22 patients; the most common finding was intrahepatic bile duct dilatation (77%), followed by intrahepatic bile duct stenosis (64%), extrahepatic bile duct wall enhancement (67%), extrahepatic bile duct wall thickening (50%), extrahepatic bile duct stenosis (50%), and intrahepatic bile duct beading (36%). Increased enhancement of the liver parenchyma on dynamic arterial-phase images, predominantly in the peripheral areas of the liver, was identified in 56% of patients. Other findings included periportal lymphadenopathy (77%), periportal high signal intensity on T2-weighted images (68%), hypertrophy of the caudate lobe (68%), and abnormal hyperintensity of the liver parenchyma on T1-weighted images (23%). CONCLUSION: On MR imaging, primary sclerosing cholangitis showed several characteristic features, including bile duct abnormalities and increased enhancement of the liver parenchyma. MR cholangiography and contrast-enhanced dynamic MR techniques are useful for revealing intra- and extrahepatic signs of primary sclerosing cholangitis.     

MRCP findings in recurrent pyogenic cholangitis

OBJECTIVE: In this essay, we present the spectrum of intrahepatic and extrahepatic bile duct abnormalities seen on MRCP in patients with recurrent pyogenic cholangitis. CONCLUSION: MRCP is a promising, noninvasive alternative to more invasive direct cholangiography for evaluating the intrahepatic and extrahepatic bile ducts in patients with recurrent pyogenic cholangitis.     

Common bile duct obstruction: assessment by transcholecystic cholangiography

Percutaneous transcholecystic cholangiography was performed in 20 patients. Fifteen patients had normal-sized bile ducts on sonograms and computed tomographic scans, and five had partial common bile duct obstruction. Gallbladder pressures were measured in 14 patients. In all cases the intrahepatic and extrahepatic bile ducts were well visualized. Only one clinically significant complication, bile peritonitis, occurred, and it was relieved by inserting a cholecystostomy catheter. Techniques as well as the potential indications for transcholecystic cholangiography are discussed. The authors believe the transcholecystic approach is a useful alternative to transhepatic cholangiography.     

MR cholangiography in children and young adults with biliary disease

OBJECTIVE: Our objective was to describe the MR cholangiography findings for young patients with suspected biliary disease who underwent half-Fourier acquisition fast spin-echo technique with respiratory triggering. SUBJECTS AND METHODS: Twenty-eight MR cholangiography studies were performed in 22 patients on a 1.5-T MR unit. Ten of these 22 patients had undergone liver transplantation. RESULTS: MR cholangiography revealed abnormalities of both the extrahepatic and the intrahepatic major and minor bile duct systems, despite the small diameter of the duct system in this group of patients. Four patterns of biliary disease were shown: global dilatation of extrahepatic or intrahepatic ducts (n = 7); segmental, uniform dilatation of central or peripheral intrahepatic ducts (n = 9); segmental, nonuniform dilatation of central or peripheral intrahepatic ducts (n = 2); and fusiform ectasia with segmental, irregular intrahepatic dilatation and bile lakes (n = 2). The findings of eight studies were interpreted as normal. The four patterns of abnormalities were correlated with the results from percutaneous transhepatic cholangiography, T-tube cholangiography, and liver biopsy and with clinical and surgical information, as available. CONCLUSION: MR cholangiography is a noninvasive technique for evaluation of biliary disease. The improved resolution afforded by respiratory triggering permits evaluation of both major and minor bile ducts, even in young, uncooperative subjects. Four patterns of abnormalities were prospectively identified, correlated with other information, and used to direct clinical treatment.     

Computed tomographic diagnosis of obstructive jaundice in the absence of intrahepatic ductal dilatation.

Six patients with obstructive jaundice had computed tomography (CT) scans showing a dilated extrahepatic biliary tree in the absence of intrahepatic ductal dilatation. Dilated extrahepatic bile ducts were most easily identified by means of intravenous injection of urographic contrast material, which permitted them to be seen as low density structures. Findings in these patients emphasize that (1) demonstration of dilated intrahepatic bile ducts is not a prerequisite for the CT diagnosis of obstructive jaundice and (2) careful CT evaluation of the extrahepatic biliary tree is necessary to identify patients with isolated dilatation of the common hepatic or common bile duct.     

Using contrast-enhanced MR cholangiography with IV mangafodipir trisodium (Teslascan) to evaluate bile duct leaks after cholecystectomy: a prospective study of 11 patients

OBJECTIVE: The purpose of our study was to determine whether contrast-enhanced MR cholangiography using IV mangafodipir trisodium can accurately detect the presence and location of bile duct leaks in patients who have undergone cholecystectomy. SUBJECTS AND METHODS: Our study group included 11 patients with suspected bile duct leaks after cholecystectomy. Axial single-shot fast spin-echo and gradient-echo images were acquired in all patients before and 1-2 hr after IV administration of mangafodipir trisodium. The contrast-enhanced MR cholangiograms were evaluated for image quality, degree of ductal or small bowel opacification, and the presence and location of bile duct leaks, strictures, and stones. MR cholangiograms were correlated with conventional contrast-enhanced cholangiograms obtained in all patients, including endoscopic retrograde cholangiography (n = 10) and percutaneous transhepatic cholangiography (n = 1). RESULTS: Excretion of mangafodipir trisodium was noted in the intrahepatic and extrahepatic bile ducts in all patients from 1 to 2 hr after IV administration. Bile ducts and fluid collections that contained excreted mangafodipir trisodium showed increased signal intensity on gradient-echo sequences and decreased signal intensity on single-shot fast spin-echo sequences. Conventional contrast-enhanced cholangiography showed the presence of bile duct leaks in six patients and the absence of bile duct leaks in five patients, with false-negative findings in one patient and false-positive findings in one patient for bile duct leak (sensitivity, 86%; specificity, 83%). CONCLUSION: Contrast-enhanced MR cholangiography with IV mangafodipir trisodium can successfully detect the presence and location of bile duct leaks in patients suspected of having such leaks after undergoing cholecystectomy. More research is necessary before acceptance of this examination as routine in the workup of these patients.     

MR Imaging Findings of Clonorchiasis

Objective

The purpose of this study was to evaluate the MR spectrum and MR cholangiographic imaging findings of clonorchiasis.

Materials and Methods

We reviewed 26 patients with confirmed clonorchiasis by either stool tests (n=24) or surgery (n=2). MR imaging was performed on a 1.5 T system (GE Medical Systems, Milwaukee, WI) with a torso coil. Axial T1- and T2-weighted, gadolinium-enhanced dynamic images and MR cholangiography were obtained. Image analyses were used to identify abnormalities of the intrahepatic and extrahepatic bile ducts and the presence of hepatobiliary malignancy. All MR examinations were reviewed by the consensus of two abdominal radiologists.

Results

Intrahepatic bile duct abnormalities were seen in 23 (89%) of the 26 patients. The most common finding was mild dilatation of the intrahepatic bile duct which was found in 21 (81%). "Too many intrahepatic ducts" were found in 16(62%), wall enhancement and thickening in 21 (81%) and filling defects and ductal stricture in the intrahepatic bile duct in 6 (24%) and 3 (12%) patients, respectively. Extrahepatic ductal dilation was found in 5 (19%) and 9 (35%) revealed hepatobiliary malignancy.

Conclusion

MR imaging revealed various findings of clonorchiasis, including dilatation, wall enhancement, stricture of the intrahepatic ducts and filling defect within the intrahepatic bile duct.     

Interactive magnetic resonance cholangiography (MRC) with adaptive averaging

PURPOSE: To implement and evaluate a technique for adaptively averaging 2D magnetic resonance cholangiography (MRC) images obtained using an interactive imaging system with a view to improving image quality at reduced fields of view (FOVs). MATERIALS AND METHODS: Images were obtained using an interactive implementation of a single-shot half-Fourier rapid acquisition with relaxation enhancement (RARE) technique. Software was developed for adaptively averaging images, and an evaluation was performed in a phantom and a cohort of 10 patients referred for standard MRC. Adaptively averaged and standard single-shot MRC images were evaluated with respect to their ability to demonstrate the common bile duct and main left and right intrahepatic duct branches. RESULTS: In all patient studies there was no difference in the ability of either the adaptive technique or the standard single-shot method to demonstrate the common bile duct and the main left and right intrahepatic duct branches. However, in seven of the 10 patient studies the adaptive technique provided better visualization of the peripheral bile duct system (P = 0.035; sign test). There was no difference in the diagnostic confidence of the two techniques (P = 0.32, Wilcoxon signed-rank test). CONCLUSION: Adaptive averaging of MRC images obtained using an interactive imaging paradigm significantly improves visualization of peripheral intrahepatic ducts.     

Sonography of the common bile duct: value of the right anterior oblique view.

The common hepatic and proximal common bile ducts (common duct) lie anteriorly and generally to the right of the portal vein in the porta hepatis. This constant anatomic relationship can be used to demonstrate the common duct and to differentiate it from the portal vein by gray scale ultrasonography. The patient is scanned longitudinally from the right anterior abdominal wall with the ultrasound beam directed posteromedially until two tubular structures are demonstrated in the porta hepatis. The more anterior tubular structure in this projection is the common duct. If the common duct is less than 3 mm in diameter, it may not be clearly delineated. In these cases the absence of common duct dilatation can be inferred. The usefulness of this view for detecting common duct dilatation was evaluated in a series of 101 consecutive cases proven by surgery, autopsy, or cholangiography. The overall accuracy was 96% (four false negative studies; no false positives). We conclude that sonography should be the imaging procedure of choice for suspected extrahepatic biliary obstruction if the serum bilirubin level precludes intravenous cholangiography.     

Bone marrow edema and associated pain in early stage osteonecrosis of the femoral head: prospective study with serial MR images

PURPOSE: To determine the accuracy of magnetic resonance (MR) cholangiography for demonstration of the biliary tract and detection of biliary complications in patients who have undergone orthotopic liver transplantation. MATERIALS AND METHODS: Breath-hold half-Fourier rapid acquisition with relaxation enhancement MR cholangiography was performed in 25 patients who had undergone orthotopic liver transplantation. MR cholangiograms were prospectively and independently interpreted by two radiologists for depiction of the biliary tract and ductal anastomosis and for complications (eg, biliary dilatation, stricture, stones). MR cholangiographic findings were correlated with findings from direct cholangiography (n = 24) and surgery (n = 1). RESULTS: MR cholangiography completely demonstrated first-order intrahepatic bile ducts in 23 (92%) patients, the donor extrahepatic bile duct in 25 (100%), the recipient extrahepatic bile duct in 17 of 18 (94%), and the anastomosis in 24 (96%). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of biliary dilatation and stricture were each 100%. Complete interobserver agreement occurred in the detection of biliary dilatation and stricture. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of stones were 100% for one radiologist and 86%, 100%, 96%, 100%, and 95%, respectively, for the other. Both radiologists agreed on the diagnosis of bile duct stones in six of seven cases (kappa = 0.90). CONCLUSION: MR cholangiography enables accurate depiction of the biliary tract and detection of biliary complications in patients with an orthotopic liver transplant.     

MR cholangiopancreatography in patients with primary sclerosing cholangitis: interobserver variability and comparison with endoscopic retrograde cholangiopancreatography

OBJECTIVE: The purpose of our study was to determine the degree of interobserver variability and correlation between MR cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP) for the presence of bile duct strictures in patients with primary sclerosing cholangitis. MATERIALS AND METHODS: For this retrospective study involving 26 patients with primary sclerosing cholangitis, 31 MR cholangiopancreatograms were compared with 30 endoscopic retrograde cholangiopancreatograms. The MR cholangiopancreatograms were independently interpreted by two abdominal radiologists in a blinded, randomized manner for overall image quality, extent of ductal visualization, and the presence and location of bile duct strictures. Unweighted multirater kappa coefficient values were estimated for each comparison. RESULTS: Visualization of more than 50% of the expected ductal length was possible in the extrahepatic, central intrahepatic, and peripheral intrahepatic bile ducts in 99%, 88%, and 69% of the MR cholangiopancreatograms and 100%, 86%, and 52% of the endoscopic retrograde cholangiopancreatograms, respectively. Strictures were detected in the extrahepatic, central, and peripheral ducts in 53%, 68%, and 87% of the MR cholangiopancreatograms and 73%, 67%, and 63% of the endoscopic retrograde cholangiopancreatograms, respectively. The interobserver agreement for stricture detection was 61% for MR cholangiopancreatography and 76% for ERCP. MR cholangiopancreatographic findings were consistent with ERCP findings for the presence of strictures in 69% of the cases. CONCLUSION: In patients with primary sclerosing cholangitis, MR cholangiopancreatography better shows the bile ducts and can depict more strictures, especially of the peripheral intrahepatic ducts, than ERCP. MR cholangiopancreatography can be used to noninvasively diagnose and follow up patients with primary sclerosing cholangitis.     

Caroli syndrome

In 1958 Caroli described the syndrome of congenital, either segmental or involving the entire bile duct system, saccular extensions of the intrahepatic bile ducts. He differentiated between two types of this disease pattern. The first form concerns pure cystic dilatations of the intrahepatic bile ducts, whereas the second one is combined with hepatic fibrosis and portal hypertension. Both types are characterised by cystic dilatations in the kidneys and in the extrahepatic bile ducts, pancreas and spleen.     

Comparison of MR cholangiopancreatographic techniques with contrast-enhanced cholangiography in the evaluation of sclerosing cholangitis.

OBJECTIVE: The purpose of our study was to compare MR cholangiopancreatography and contrast-enhanced cholangiography in patients with sclerosing cholangitis. MATERIALS AND METHODS: Twenty patients with sclerosing cholangitis were evaluated on MR cholangiopancreatography using the single-shot fast spin-echo technique at 1.5 T. A group of 19 healthy volunteers underwent MR cholangiopancreatography as controls. Thick-slab (2-cm sections) coronal oblique and thin-slab (5-mm sections) interleaved straight coronal MR images were obtained. All patients with sclerosing cholangitis had an MR cholangiopancreatogram within 12 months of a contrast-enhanced cholangiogram (mean, 3.8 months). Seventy-five percent of patients had an MR cholangiopancreatogram within 3 months of the contrast-enhanced cholangiogram. The MR cholangiopancreatograms and contrast-enhanced cholangiograms were reviewed independently in a random fashion by two radiologists who were unaware of clinical history for the degree of ductal visualization and for the presence and location of strictures of the intrahepatic and extrahepatic bile ducts. All discrepancies were resolved by a consensus, and the contrast-enhanced cholangiograms were regarded as the gold standard. Statistically significant data were calculated using the signed rank test (p < 0.01), and agreement analysis was calculated using Cohen's kappa. RESULTS: All findings on MR cholangiopancreatograms in healthy subjects were interpreted as normal, and all findings on MR cholangiopancreatograms in patients with sclerosing cholangitis were interpreted as abnormal. When compared with the control group, scans of patients with sclerosing cholangitis usually showed good visualization (>50%) of the intrasegmental (86% vs 9%) and peripheral (67% vs 0%) intrahepatic ducts on thick-slab MR cholangiopancreatography. Thick-slab MR cholangiopancreatography showed good visualization in more ducts than contrast cholangiography (84% vs 70%; p = 0.10) and showed more strictured ducts than contrast cholangiography (47% vs 36%; p = 0.22). When comparing those ducts with good visualization on both MR cholangiopancreatography and contrast cholangiography, we found that disagreement occurred regarding 32% of ducts. Most of the discrepancies (60%) resulted when a stricture was noted on MR cholangiopancreatography but not on contrast-enhanced cholangiography. Good interobserver agreement (kappa > 0.4) was noted for detecting strictures of the extrahepatic, left hepatic, left medial, and right posterior ducts, with the greatest agreement for extrahepatic ductal strictures (kappa = 0.8). CONCLUSION: Thick-slab MR cholangiopancreatography is the best technique for depicting normal and strictured bile ducts and allows the differentiation of healthy patients from patients with sclerosing cholangitis. Although endoscopic retrograde cholangiopancreatography was considered the standard, MR cholangiopancreatography was superior for intrahepatic biliary ductal visualization. Therefore, this technique is of value in the diagnosis and follow-up of patients with sclerosing cholangitis.     

Imaging and Estimation of the Prognostic Features of Primary Sclerosing Cholangitis by Ultrasonography and Mr Cholangiography

Purpose: To evaluate the ability of US and MR cholangiography (MRC) to detect bile duct changes and prognostic signs of primary sclerosing cholangitis (PSC) seen at endoscopic retrograde cholangiography (ERC).Material and Methods: In a prospective study, 9 patients with PSC underwent US, MRC, MR imaging and ERC of the bile ducts and the liver. Eight age- and sex-matched control patients were examined with MRC, MR imaging and ERC. A segmental comparison was performed to assess the ability of MRC-MR and US to reveal the accurate ductal involvement in different segments of the biliary tree and the specific criteria of poor prognostic outcome in PSC. The ability of MRC-MR to detect the presence of PSC in different patients was analysed blindly.Results: MRC-MR depicted changes of PSC correctly in 9 patients (radiologist 1) and in 8 patients with 1 false-positive finding (radiologist 2) in the blinded analysis. In the segmental comparison, MRC missed especially bile duct dilatations. MRC was too pessimistic in the evaluation of the outcome. US detected features suggestive of PSC in 8 patients (radiologist 3). US was unable to show the predictors of poor outcome.Conclusion: MRC and US seem to be useful in the detection of PSC. US is unable and MRC is too pessimistic to estimate the outcome of PSC.     

Oriental cholangiohepatitis: sonographic findings in 48 cases

Oriental cholangiohepatitis is characterized by recurrent attacks of abdominal pain, fever, chill, and jaundice and grossly dilated extrahepatic and intrahepatic ducts containing soft, pigmented stone and pus. Sonograms were studied in 48 patients in whom the diagnosis was later proved during surgery (n = 34) or on the basis of clinical and laboratory findings and endoscopic retrograde cholangiography (n = 14). The sonographic findings included intrahepatic and/or extrahepatic bile duct stones (n = 47); moderate to severe dilatation of the extrahepatic ducts with relatively mild or no dilatation of intrahepatic bile ducts (n = 41); localized dilatation of the lobar or segmental bile ducts, especially the left hepatic lobe (n = 16); and gallstones (n = 22). Our experience suggests that the preoperative diagnosis of oriental cholangiohepatitis can be strongly suggested by sonographic findings.     

Types and frequencies of biliary tract variations associated with a major portal venous anomaly: analysis with multi-detector row CT cholangiography

PURPOSE: To retrospectively determine whether major portal venous variation was more frequently associated with biliary variants, with consideration of the types and frequencies of biliary tract variations in the right and left liver lobes. MATERIALS AND METHODS: Before undergoing computed tomographic (CT) cholangiography, patients gave informed consent. The retrospective research protocol was approved, and informed consent was waived by the ethics committee. Forty-four patients aged 29-80 years who underwent multi-detector row CT cholangiography had a major portal vein variation in which the main portal vein diverged into the common trunk of the left portal vein and right anterior sectorial portal vein. One hundred fifty-eight consecutive patients aged 26-89 years who did not have this variation served as the control group. Three radiologists retrospectively evaluated the confluence pattern of the bile duct, the relationship between this pattern and the portal vein, and the major branching pattern of the portal vein. Pearson chi2 and Fisher exact tests were performed to identify significant differences between the two patient groups. RESULTS: The classic hilar confluence pattern, where the right posterior sectorial duct connects supraportally with the right anterior sectorial duct, was less frequent in the patients with the portal vein variation than in the control subjects (32% vs 73%, P < .05). The following biliary tract variations were identified more frequently in the variation group than in the control group (P < .05): right posterior sectorial duct joining left hepatic duct with a supraportal course (34% vs 12%), right posterior sectorial duct joining right anterior sectorial duct with an infraportal course (13% vs 4%), right posterior sectorial duct following an infraportal course (23% vs 8%), and left lateral segmental ducts caudal to the umbilical portion of the portal vein (14% vs 3%). The right hepatic duct, which receives all biliary ducts from the right lobe, was significantly less frequently developed in the variation group (46% vs 79%, P < .05). In addition, retroportal bile ducts were seen in four patients with the portal vein variation (P < .05). CONCLUSION: Bile duct configurations in patients with portal vein variation were significantly different from those in control subjects.