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.     

Biliary atresia in neonates and infants: triangular area of high signal intensity in the porta hepatis at T2-weighted MR cholangiography with US and histopathologic correlation

PURPOSE: To correlate a triangular area of high signal intensity in the porta hepatis on T2-weighted magnetic resonance (MR) cholangiograms of biliary atresia with ultrasonographic (US) and histopathologic findings in a portal mass observed during a Kasai procedure. MATERIALS AND METHODS: Twenty-one consecutive neonates and infants (age range, 13-88 days; mean age, 59 days) with cholestasis underwent US and single-shot MR cholangiography. In 12 patients with biliary atresia diagnosed at histopathologic examination, MR cholangiographic findings in the porta hepatis were correlated with US and histopathologic findings in the portal mass. RESULTS: At US, eight of the 12 patients had round, linear, or tubular hypoechoic portions within a triangular cord; MR cholangiography revealed a triangular area of high signal intensity confined to the porta hepatis. Histopathologic examination of the portal mass revealed a cystic or cleftlike lesion surrounded by loose myxoid mesenchyme and platelike fetal bile ducts. Neither the large cystic lesion without ductal epithelium nor the small cleftlike lesion with scanty epithelium demonstrated bile staining. Similar areas of high signal intensity were not seen on T2-weighted images in the remaining patients (four with biliary atresia and nine with neonatal hepatitis). CONCLUSION: In biliary atresia, T2-weighted single-shot MR cholangiography can show a triangular area of high signal intensity in the porta hepatis that may represent cystic dilatation of the fetal bile duct.     

Differential diagnosis of periampullary carcinomas at MR imaging.

Periampullary carcinomas arise within 2 cm of the major duodenal papilla and comprise carcinomas of the ampulla, distal common bile duct, pancreas, and duodenum. Their clinical features and anatomic locations are similar, as are the therapeutic approaches; however, their long-term outcomes vary. Magnetic resonance (MR) images of 89 pathologically proved periampullary carcinomas (29 ampullary carcinomas, 27 distal common bile duct carcinomas, 21 pancreatic carcinomas, six duodenal carcinomas, and six unclassified carcinomas) were reviewed. Ampullary carcinoma manifests as a small mass, periductal thickening, or bulging of the duodenal papilla. Pancreatic carcinoma is characterized by a discrete parenchymal mass, which enhances poorly on dynamic gadolinium-enhanced images. Sometimes, two proximal and two distal pancreatic and biliary ducts appear as four separate ducts (the four-segment sign). Dilatation of side branches of the pancreatic ducts is frequently seen in pancreatic carcinoma but not in other periampullary carcinomas. Distal bile duct carcinoma manifests as luminal obliteration and wall thickening or as an intraductal polypoid mass. A dilated proximal bile duct, a nondilated distal bile duct, and a dilated or nondilated pancreatic duct may form the three-segment sign. MR cholangiopancreatography and sectional MR imaging are useful in determining the origins of periampullary carcinomas.     

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.     

Choledochal cyst: comparison of MR and conventional cholangiography

AIMS: To assess the diagnostic value of magnetic resonance (MR) cholangiography versus conventional cholangiography in patients with choledochal cyst and to determine whether MR cholangiography can be considered an alternative to conventional cholangiography. MATERIALS AND METHODS: Thirteen patients with choledochal cyst were examined by MR cholangiography and conventional cholangiograms. Magnetic resonance cholangiography employed T2-weighted axial and coronal fast spin-echo, single and multislab single-shot fast spin-echo sequences, including source images with maximum intensity projections. The diagnostic value of MR cholangiography and conventional cholangiograms was assessed and compared using the criteria of depiction of morphology, anomalous pancreaticobiliary duct union and demonstration of complications such as stones. A four-point diagnostic scale was applied to the delineation of the ductal anatomy with the Wilcoxon signed-ranks test and McNemar's test used for statistical analysis. RESULTS: The depiction of the choledochal cyst was significantly better with MR cholangiography than with conventional cholangiography (P = 0.03). The detection rate of an anomalous pancreaticobiliary duct union was not significantly different with either method (P = 0.641), nor was the detection rate of bile duct stones (P = 0.375). CONCLUSION: Magnetic resonance cholangiography provides data equivalent to or superior to those from conventional cholangiography in evaluating choledochal cyst. Magnetic resonance cholangiography is recommended as a non-invasive examination of choice for the evaluation of choledochal cyst.     

Preoperative evaluation of gallbladder carcinoma: efficacy of combined use of MR imaging,MR cholangiography,and contrast-enhanced dual-phase three-dimensional MR angiography

PURPOSE: To determine the efficacy of the combined use of magnetic resonance (MR) imaging, MR cholangiography (MRC), and MR angiography (MRA) in the preoperative evaluation of gallbladder carcinoma. MATERIALS AND METHODS: During a 20-month period, 41 patients with proven gallbladder carcinomas were referred for MR examination, including MR imaging, MRC, and gadolinium-enhanced dual-phase MRA to determine the operability of their gallbladder carcinoma. Eighteen patients who underwent surgery within six days of the MR examination were included in this study. All MR images were analyzed in order to assess bile duct invasion, vascular invasion, hepatic invasion or metastasis, lymph node metastasis, and invasion into adjacent organs. RESULTS: Surgical and histopathologic findings revealed hepatic invasion in nine patients, bile duct invasion in nine, vascular invasion in three, and lymph node metastasis in 10. The sensitivity and specificity of MR examination were, respectively, 100% and 89% for bile duct invasion, 100% and 87% for vascular invasion, 67% and 89% for hepatic invasion, and 56% and 89% for lymph node metastasis. CONCLUSION: The "all-in-one" MR protocol, including MR imaging, MRC, and MRA, can be an effective diagnostic method in the preoperative work-up for gallbladder carcinoma.     

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.     

Ampullary carcinoma: Demonstration by current MR techniques

The objective of this study was to demonstrate the appearance of ampullary carcinoma using current MR techniques, including fat suppression, gadolinium enhancement, and MR cholangiography. Nine patients with ampullary carcinoma were examined by MRI at 1.5 T. MR examinations included T1-weighted spoiled gradient echo, T1-weighted fat-suppressed, and immediate postgadolinium spoiled gradient echo images for all patients and MR cholangiography for three patients. The imaging features of ampullary carcinomas, including tumor size and morphology, signal intensity, and enhancement characteristics, were determined. Ampullary carcinomas shown on MR images ranged in size from 1.5 to 5.5 cm. Tumors were low in signal intensity on precontrast T1-weighted spoiled gradient echo and T1-weighted fat-suppressed images relative to normal pancreatic tissue and enhanced less than normal pancreas on immediate postgadolinium spoiled gradient echo images. Tumor conspicuity was greatest on immediate postgadolinium spoiled gradient echo images. MR cholangiography demonstrated high grade obstruction of the common bile duct and mild dilatation of the pancreatic duct at the level of the ampulla with abrupt termination of the ducts in two untreated patients and moderate dilatation of the common bile duct in one patient who had a biliary stent. Ampullary carcinomas can be demonstrated on MR images as small masses arising at the ampulla. Tumors are well defined on immediate postgadolinium spoiled gradient echo images.     

Obstructive dilatation of extrahepatic recipient and donor bile ducts complicating orthotopic liver transplantation: imaging and laboratory findings

Biliary obstruction in liver transplants is most commonly due to stricture at the biliary anastomosis. The native common bile duct typically is normal. We retrospectively studied 28 patients with choledochocholedochostomy anastomoses who had marked native and donor extrahepatic bile duct dilatation associated with clinical evidence of biliary obstruction. Operative cholangiograms were compared with postoperative cholangiograms obtained a mean of 50 weeks (range, 2-246 weeks) later. Mean caliber of the native common bile duct increased from 7.5 +/- 2.0 mm on operative cholangiograms to 14.8 +/- 3.9 mm on postoperative cholangiograms (p less than .001). Mean caliber of the donor common hepatic duct increased from 5.9 +/- 1.3 mm on operative cholangiograms to 12.8 +/- 3.8 mm on postoperative cholangiograms (p less than .001). Dilatation of the cystic duct remnant was seen in 15 patients. All patients had surgical revision to choledochojejunostomy with improved results of liver function studies in most cases. Diffuse dilatation of native and donor extrahepatic bile ducts may develop in liver transplant recipients. Typical features include native and donor extrahepatic ducts greater than 12 mm in diameter and a dilated cystic duct remnant on postoperative cholangiography in a patient with otherwise unexplained hepatic dysfunction.     

Detection of choledocholithiasis with MR cholangiography: comparison of three-dimensional fast spin-echo and single- and multisection half-Fourier rapid acquisition with relaxation enhancement sequences

PURPOSE: To compare the performance of three pulse sequences commonly used at magnetic resonance (MR) cholangiography in the diagnosis of choledocholithiasis. MATERIALS AND METHODS: MR cholangiography was performed in 57 patients who were suspected of having choledocholithiasis and referred for endoscopic retrograde cholangiography. Non-breath-hold three-dimensional fast spin-echo, breath-hold single-section half-Fourier rapid acquisition with relaxation enhancement (RARE), and breath-hold multisection half-Fourier RARE sequences were compared. Two radiologists independently interpreted the MR cholangiograms. Evaluated diagnostic performance parameters included sensitivity, specificity, receiver operating characteristic (ROC) curves, and interobserver agreement (kappa statistics). Endoscopic retrograde cholangiography was the standard of reference. RESULTS: Eight patients were excluded because of incomplete MR examinations (n = 4) or failure in the cannulation of the bile duct at retrograde cholangiography (n = 4). In 49 patients, the three MR cholangiographic sequences were completed successfully. In 24 (49%) of these patients, retrograde cholangiography demonstrated stones. Sensitivity and specificity of MR cholangiography exceeded 90%, and the area under the ROC curve was greater than 0.95 for both radiologists and for the three sequences. Interobserver agreement for presence of bile duct stones was at least 0.80 (very good) for the three sequences. CONCLUSION: The three MR cholangiographic sequences had similarly high sensitivities and specificities for the detection of choledocholithiasis.     

硬化性胆管炎与胆总管癌的影像鉴别诊断

目的探讨CT和胆道造影对硬化性胆管炎和胆总管浸润癌的影像特征并评价其诊断区别。方法对18例经手术病理证实的胆总管癌与4例临床诊断的硬化性胆管炎的CT和PTC、ERCP、MRCP的影像学表现进行分析。结果4例硬化性胆管炎表现胆总管壁较薄,边界更加光整,管壁向心性增厚,狭窄近段胆管轻度扩张;CT增强扫描呈明显强化,胆道造影表现管腔渐进性、均匀的狭窄,与胆管癌比较表现多灶性狭窄并有沙漏样改变。结论CT和胆道造影能有效区分硬化性胆管炎和胆总管浸润癌病变,密切结合临床综合分析,对于两种疾病的鉴别诊断有重要的价值。     

Right lobe living donor liver transplantation: preoperative evaluation of the donor with MR imaging

OBJECTIVE: The purpose of this study was to report our experience in preoperative evaluation of right hepatic lobe donors with a comprehensive MR examination and to compare abdominal MR images, MR cholangiograms, and MR angiograms with findings at surgery, intraoperative cholangiography, and digital subtraction angiography. MATERIALS AND METHODS: Twenty-eight right hepatic lobe donors underwent preoperative evaluation with MR imaging, MR cholangiography, and MR angiography. Two abdominal radiologists independently and randomly reviewed these studies. Points of assessment included focal and diffuse liver disease, calculation of right lobe volumes, depiction of the biliary tract and ductal anomalies, and depiction of the liver vasculature and vascular anomalies. Comparison was made with intraoperative cholangiograms (n = 20) and digital subtraction angiograms (n = 28). RESULTS: MR imaging revealed and characterized focal liver lesions in eight of 28 patients. Calculated right lobe volumes agreed with surgically determined volumes within 7% for reviewer 1 and within 15% for reviewer 2. Intrahepatic bile ducts were depicted completely with MR cholangiography in 25 of 28 patients and with intraoperative cholangiography in nine of 20 patients. MR cholangiography revealed ductal anomalies in six patients. MR imaging and MR angiography depicted the portal veins more completely than digital subtraction angiography. MR imaging and MR angiography correctly excluded portal venous anomalies in all patients and revealed surgically confirmed accessory hepatic veins in six of 28 patients. Angiographically confirmed arterial anomalies were correctly detected in three of 28 patients by at least one reviewer on MR imaging and MR angiography. CONCLUSION: MR imaging, MR cholangiography, and MR angiography provide a comprehensive, accurate means of evaluating donors for factors that may preclude or complicate right hepatic lobe donation.     

MR imaging findings of early bile duct cancer

Purpose

To retrospectively evaluate the MR imaging features of early bile duct cancer and to correlate them with the clinicopathologic findings.

Materials and Methods

This retrospective study was approved by our institutional review board, and informed consent was waived. Seventeen patients with surgically proven early bile duct cancer who had undergone preoperative MR cholangiopancreatography with gadolinium‐enhanced MR imaging, were included in this study. Two, experienced radiologists evaluated the MR images in consensus regarding the following findings: tumor number and morphology; signal intensity of the tumor; sharpness of the outer border of the bile duct wall; enhancement pattern of the tumor; and the presence of enlarged peribiliary lymph nodes. Another radiologist measured the SNR of the tumor and bile duct wall on gadolinium‐enhanced MRI during the dynamic phases to evaluate the tumor enhancement degree.

Results

In all patients, MR imaging demonstrated single or multiple intraluminal bile duct masses showing a sharply defined outer margin. The most common enhancement pattern of the biliary lesions showed heterogeneous amorphous enhancement or heterogeneous enhancement with central, dot‐like structures or vascular structures (76.5%, 13/17 patients). The difference of SNR between bile duct and tumor was greatest in the equilibrium phase (P < 0.05).

Conclusion

MRCP combined with dynamic contrast‐enhanced MRI can be useful for detecting early bile duct cancers. Common MR findings of early bile duct cancer include one or more inhomogeneously enhancing intraductal masses with clear outer margins and preservation of the bile duct wall. J. Magn. Reson. Imaging 2008;28:1466–1475. © 2008 Wiley‐Liss, Inc.     

Sclerosing cholangitis associated with hepatic arterial FUDR chemotherapy: radiographic-histologic correlation

During a 2-year period, cholangiography was performed on 17 patients with clinical evidence of cholestasis who were receiving hepatic intraarterial floxuridine (IA-FUDR) infusions for treatment of metastatic colorectal adenocarcinoma. The development of cholestasis was associated with persistently elevated alkaline phosphatase, but serial CT examinations of the liver showed no progression of the tumor. All patients had cholangiographic abnormalities (by endoscopic retrograde cholangiopancreatography, percutaneous transhepatic cholangiography, or operative cholangiography) of the biliary ductal system similar to those in idiopathic sclerosing cholangitis. Certain features, however, appear specific to IA-FUDR-induced cholestasis. All patients studied had segmental involvement at the common hepatic duct bifurcation. The cystic duct and gallbladder were often involved, but the distal common bile duct was spared. Histologic features of periportal and periductal fibrosis were present in specimens obtained from percutaneous liver biopsy in three patients, cholecystectomy in four patients, and autopsy in two patients. When clinical signs of hepatic dysfunction occur in the absence of tumor progression, biliary sclerosis must be suspected.     

Early biliary complications of laparoscopic cholecystectomy: evaluation on T2-weighted MR cholangiography in conjunction with mangafodipir trisodium-enhanced 3D T1-weighted MR cholangiography

OBJECTIVE: Our aim was to assess preliminary experience with combined conventional T2-weighted and mangafodipir trisodium (MnDPDP)-enhanced T1-weighted MR cholangiography in evaluating early biliary complications of laparoscopic cholecystectomy. SUBJECTS AND METHODS: Conventional heavily T2-weighted MR cholangiography with MnDPDP-enhanced T1-weighted MR cholangiography and ERCP were performed in seven patients with high clinical suspicion of biliary complications after laparoscopic cholecystectomy. The final diagnoses of complications were classified according to the presence and degree of bile duct injury, bile leakage, and retained stones. RESULTS: The diagnoses on MR cholangiography were as follows: complete transection and occlusion of the common bile duct with bile leakage (n = 3), partial strictures of the common bile duct with bile leakage (n = 1), cystic duct leakage (n = 1), partial ligation of an aberrant right hepatic duct (n = 1), and hemorrhage without biliary complication (n = 1). The final diagnoses at surgery (n = 2) and ERCP (n = 5) were as follows: complete transection and occlusion of the common bile duct with bile leakage (n = 2), partial strictures of the common bile duct with bile leakage (n = 2), cystic duct leakage (n = 1), partial ligation of an aberrant right hepatic duct (n = 1), and hemorrhage without biliary complication (n = 1). MR cholangiography accurately yielded the same findings as the final diagnoses, except in one case with partial stricture of the bile duct with bile leakage (overdiagnosed as complete occlusion on MR cholangiography). CONCLUSION: Combined conventional T2-weighted and MnDPDP-enhanced T1-weighted MR cholangiography may eliminate the use of other studies for the imaging of biliary complications after cholecystectomy if this preliminary data can be verified in a larger study.     

Early gastric carcinoma: evaluation with high-spatial-resolution MR imaging in vitro.

PURPOSE: To determine signal intensity characteristics of the gastric wall layers and to assess the accuracy of the evaluation of early gastric carcinomas in vitro by using resected specimens studied with high-spatial-resolution magnetic resonance (MR) imaging. MATERIALS AND METHODS: Fifteen gastric specimens obtained from patients suspected of having early gastric carcinoma were studied with a 1.5-T MR system with a 4-cm-diameter loop coil. High-spatial-resolution spin-echo MR images were obtained with a field of view of 50 mm, a matrix of 256 x 256, and a section thickness of 2 mm, resulting in a voxel size of 0.08 mm(3). Findings from MR images were compared with histopathologic findings. RESULTS: T1- and T2-weighted MR images clearly depicted the normal gastric wall as consisting of four and six layers, respectively, which corresponded well to the histologic layers. In 14 (93%) of 15 gastric carcinomas, the depth of mural invasion visualized with MR imaging correlated well with the histopathologic stage. The stage determined with MR imaging, however, was lower in one instance (7%) than the histopathologic stage. MR imaging also depicted the gross features of the tumor, presence of ulceration, and adjacent lymph node swelling. CONCLUSION: High-spatial-resolution MR imaging has a high diagnostic accuracy in the evaluation of the mural invasion of early gastric carcinoma in vitro and thus potentially enables preoperative histopathologic staging.     

Diagnosis of choledocholithiasis and bile duct stenosis by magnetic resonance cholangiogram

We evaluated the diagnostic accuracy of magnetic resonance cholangiography (MRC) in the diagnosis of bile duct calculi and stenosis. Two-dimensional fast spin echo (FSE) MR cholangiograms were performed using torso multicoil array as a surface coil and respiratory triggering in 50 patients suspected of having bile duct disease. Coronal and axial images were acquired and reviewed prospectively by two radiologists. Direct cholangiographic correlation (endoscopic retrograde cholangiopancreatography [ERCP], intraoperative cholangiogram, percutaneous transhepatic cholangiogram) and surgery were available for comparison and were reviewed by two radiologists. The sensitivity, specificity and accuracy of MRC in diagnosing bile duct dilatation, choledocholithiasis and stenosis were evaluated. It yielded a sensitivity and a specificity of 100% in diagnosing bile duct dilatation. In the diagnosis of choledocholithiasis, MRC yielded a sensitivity of 95%, a specificity and an accuracy of 96%. Bile duct stenosis was diagnosed with a sensitivity and a specificity of 100%. We concluded that MRC exhibited high accuracy in diagnosing bile duct stenosis and choledocholithiasis.     

MR imaging and MR cholangiopancreatography in the preoperative evaluation of hilar cholangiocarcinoma: correlation with surgical and pathologic findings

The primary aim was to evaluate delayed contrast-enhanced MRI in depicting perineural spread of hilar cholangiocarcinoma (CCC) and consequently to determine the capability of MRI/MRCP for staging CCC. Fifteen patients that underwent MRI/MRCP and surgical treatment were retrospectively included. Two radiologists evaluated MR images to assess delayed periductal enhancement, extent of bile duct stenosis, liver parenchymal and vascular involvement and presence of liver atrophy. An agreement between delayed enhancement of the bile duct walls and perineural neoplastic spread showed a very good correlation factor (0.93). The overall accuracy in detecting biliary neoplastic invasion was higher for delayed T1-weighted images (93.3%) than for the MRCP images (80%), and T1-delayed image increased the MR accuracy in assessing the neoplastic resectability (p < 0.05). MRI correctly predicted vascular involvement in 73% and liver involvement in 80% of the cases. The number of overall correctly assessed patients with regard to resectability was 11 true positive, 1 false positive and 3 true negative. The combination of MRI/MRCP is a reliable diagnostic method for staging hilar cholangiocarcinomas. Delayed periductal enhancement is accurate in the evaluation of neoplastic perineural spread, and it can improve diagnostic accuracy to identify resectable and unresectable tumours.     

Biliary malignancies occurring in choledochal cysts

Eight cases of choledochal cyst associated with biliary malignancy (gallbladder carcinoma in three and bile duct carcinoma in five) were reviewed to evaluate the roles and limitations of computed tomography (CT) (n = 8), ultrasound (US) (n = 6), cholangiography (n = 8), and angiography (n = 6). In cases of gallbladder carcinoma, both CT and US revealed mass lesions in the gallbladder consistent with cancer. CT also depicted either a mass lesion or an irregular thickened wall in all cases of bile duct carcinoma; however, US failed to demonstrate a thickened wall in one of three cases in which CT findings were positive. Cholangiography universally revealed malunion of the pancreatico-biliary duct, and the findings were suggestive of malignancy in seven cases in which CT depicted abnormalities. Angiography showed tumor stain in three of six cases. Lymph node metastases were present in four cases but were detected preoperatively in only one. One case showing a thickened bile duct wall was erroneously diagnosed as malignancy among 27 cases of choledochal cyst unassociated with biliary malignancy.     

3.0- Versus 1.5-T MR cholangiography: a pilot study

OBJECTIVE: The purpose of our study was to evaluate quantitative and qualitative image quality of MR cholangiography at a field strength of 3.0 T compared with the standard field strength of 1.5 T. MATERIALS AND METHODS: A standardized MR cholangiography sequence protocol was used for 15 healthy male volunteers (mean age +/- SD, 32.4 +/- 4.3 years) who underwent both 1.5- and 3.0-T MRI within 2 hr in an alternating fashion. Dedicated circular polarized torso coils (1.5 and 3.0 T) were used. The sequence protocol included breath-hold single-slice rapid acquisition with relaxation enhancement (slice thickness, 50 mm; orientation, coronal and +/- 20 degrees oblique coronal); breath-hold multislice HASTE (slice thickness, 3 mm; coronal only); and a non-breath-hold, respiratory-triggered 3D turbo spin-echo (TSE) T2-weighted sequence (slice thickness, 1 mm; 60 slices per slab; coronal only). Maximum intensity projections were generated from each multislice data set. Bile duct (common bile duct, right posterior segmental branch, and left hepatic duct) to periductal tissue contrast-to-noise ratios were compared at 1.5 and 3.0 T. Qualitative image analysis was performed by three independent reviewers. Qualitative analysis included delineation of the extra- and intrahepatic biliary anatomy, with specific attention given to the presence (or absence) of cystic or intrahepatic ductal variants, using a 4-point confidence scale. Statistical analysis consisted of the paired Student's t test and the signed rank test. RESULTS: Contrast-to-noise ratios between the bile duct and the periductal tissue were higher at 3.0 T in all three locations (common bile duct, right posterior segmental branch, and left hepatic duct). In each magnet class, the 3D TSE sequence offered the best contrast-to-noise ratio and qualitative analysis. Superiority of the 3D TSE sequence was statistically significant in all analyses. Five of the 15 volunteers had intrahepatic biliary variants that were detected with a higher level of confidence (p < 0.01) on the 3.0-T system than on the 1.5-T system. CONCLUSION: Compared with MR cholangiography at 1.5 T, MR cholangiography at 3.0 T offers improved contrast-to-noise ratio and a higher level of confidence for depicting intrahepatic variants.