Gadobenate Dimeglumine as an Intrabiliary Contrast Agent: Comparison with Mangafodipir Trisodium with Respect to Non-dilated Biliary Tree Depiction

OBJECTIVE: To compare the efficacy of Mangafodipir trisodium (Mn-DPDP) -enhanced MR cholangiogrphy (MRC) and Gadobenate dimeglumine (Gd-BOPTA) -enhanced MRC in visualizing a non-dilated biliary system. MATERIALS AND METHODS: Eighty-eight healthy liver donor candidates underwent contrast-enhanced T1-weighted MRC. Mn-DPDP and Gd-BOPTA was used in 36 and 52 patients, respectively. Two radiologists reviewed the MR images and rated the visualization of the common duct, the right and left hepatic ducts, and the second-order branches using a 4-point scale. The contrast-to-noise ratio (CNR) of the common duct to the liver in the two groups was also compared. RESULTS: Mn-DPDP MRC and Gd-BOPTA MRC both showed similar visualization grades in the common duct (p = .380, Mann-Whitney U test). In the case of the proximal bile ducts, the median visualization grade was significantly higher with Gd-BOPTA MRC than with Mn-DPDP MRC (right hepatic duct: p = 0.016, left hepatic duct: p = 0.014, right secondary order branches: p = 0.006, left secondary order branches, p = 0.003). The common duct-to-liver CNR of the Gd-BOPTA MRC group was significantly higher (38.90+/-24.50) than that of the Mn-DPDP MRC group (24.14+/-17.98) (p = .003, Student's t test). CONCLUSION: Gd-BOPTA, as a biliary contrast agent, is a potential substitute for Mn-DPDP.

Usefulness of Multiplanar Reformatted Images of Multi-detector Row Helical CT in Assessment of Biliary Stent Patency

PURPOSE: To evaluate the usefulness of multi-detector row helical CT (MDCT), multiplanar reformatted images for the noninvasive assessment of biliary stent patency, and for the planning for management in patients with a self-expandable metallic stent due to malignant biliary obstruction. MATERIALS AND METHODS: Among 90 consecutive patients, from August 1999 to July 2003, 26 cases in 23 patients with malignant biliary obstruction who underwent self-expandable metallic stent insertion in the biliary system and percutaneous transhepatic biliary drainage within 7 days after CT were enrolled in this study. On CT images, the complete and functional obstruction of the stent and the precise level of obstruction were evaluated. The presence of an enhancing intraluminal mass or wall thickening around stent was determined, and the causes of obstruction were evaluated. These findings were then compared with percutaneous transhepatic cholangiography. RESULTS: Multi-detector row helical CT correctly demonstrated the patency of a stent in 24 cases (92.3%). It was adequate in helping to depict the precise level of stent occlusion in 23 cases (88.5%). Multi-detector row helical CT also revealed the extent of tumor that represented as an enhancing intraluminal mass or wall thickening around the stent in 23 cases, and this was represented as complete obstruction on percutaneous transhepatic cholangiography. In the case of functional obstruction, MDCT predicted the possible cause of the obstruction. CONCLUSION: Multiplanar reformatted images of multi-detector row helical CT is a useful imaging modality for the noninvasive assessement of stent patency and the precise level of obstruction when stent obstrution is suspected in the patients with self-expandable metallic stent due to malignant biliary obstruction. It can also predict the possible cause of the obstruction and allows adequate planning for the medical management of such cases.

Hilar Branching Anatomy of Living Adult Liver Donors: Comparison of T2-MR Cholangiography and Contrast Enhanced T1-MR Cholangiography in Terms of Diagnostic Utility

PURPOSE: To compare T2-weighted MR cholangiography (T2-MRC) and contrast-enhanced T1-weighted MRC (enhanced T1-MRC) in the assessment of biliary anatomy in donor candidates for living related liver transplantation (LRLT). MATERIALS AND METHODS: Thirty-three potential donors underwent MR examination for preoperative evaluation. Using the single-shot half-Fourier RARE sequence, T2-weighted single-section and coronal images were obtained, and enhanced T1-MRC was performed, using 3D GRE sequences after the administration of mangafodifir trisodium. To assess the hilar ductal branching pattern and determine diagnostic confidence, two reviewers first evaluated the unpaired T2-MRC and enhanced T1-MRC images, and then paired T2-MRC and enhanced T1-MRC images together. In particular, in 12 cases in which direct cholangiographys were performed, the feasibility of single duct-to-duct anastomosis was assessed using the unpaired and the paired sets sequentially. RESULTS: The reviewers' confidence tended to be higher for enhanced T1-MRC than T2-MRC, but the difference was not statistically significant. For both reviewers, confidence was significantly higher for the paired set than for T2- or enhanced T1-MRC alone (p < .001). The types of biliary anatomy determined in the paired set matched the consensus reading in 33 (100%) and 30 cases(91%) assessed by reviewer 1 and 2, respectively. The separate interpretation of T2- and enhanced T1-MRC findings matched the consensus interpretation in 30 (91%) and 28 cases (85%), respectively, assessed by reviewer 1, and 26 (79%) and 28 cases (85%), respectively, assessed by reviewer 2. The possibility of single anastomosis was accurately predicted in 91.6% of cases in T2-MRC, and 100% at enhanced T1-MRC and the combined set. CONCLUSION: In the evaluation of the biliary anatomy of potential donors for LRLT, the combined use of T2-MRC and enhanced T1-MRC may improve diagnostic confidence and decrease the occurrence of a non diagnostic or equivocal interpretation at T2-MRC alone.

Intrahepatic Cholesterol Stones: Report of Two Cases

Hepatolithiasis is rare in western countries, but is fairly common in East Asia, including Japan, China, and Taiwan. Calcium bilirubinate stones account for the majority of intrahepatic calculi, while intrahepatic cholesterol stones are very rare, the incidence being 0.37% of all gallstones. However, several investigators have recently reported an increased incidences of cholesterol gallstones in hepatolithiasis cases and have discussed the differing mechanisms for their formation in the intrahepatic biliary tree of patients with calcium bilirubinate stones and cholesterol stones. We report two cases of intrahepatic cholesterol stone, with emphasis on the radiologic findings, and review the literature.

Primary Sclerosing Cholangitis in Patients with Ulcerative Colitis: Two Case Reports

Primary sclerosing cholangitis, a chronic cholestatic liver disease, is uncommon and is characterized byinflammation and fibrosis of the bile ducts. It frequently occurs in association with ulcerative colitis. Wedescribe two cases of primary sclerosing cholangitis in patients with ulcerative colitis.

Percutaneous Transhepatic Cholangiography and Biliary Drainage by Antegrade Puncture Technique: Technical Note

The antegrade puncture technique represents a new approach to percutaneous transhepatic cholangiography andbiliary drainage. With this technique, ductal puncture begins with the liver capsule toward the hepaticparenchyma. This report briefly describes this new technique, and its safety and feasibility.

Thin Section Helical CT Findings of Klatskin Tumor and Benign Stricture: Cholangiographic Correlation

PURPOSE: The purpose of this study was 1) to describe the thin section helical CT findings of hilar cholangiocarcinoma and of benign stricture, and to discuss the differential points between the two disease entities and 2) using cholangiographic correlation, to evaluate the diagnostic accuracy of helical CT in determining the extent of hilar cholangiocarcinoma. MATERIALS AND METHODS: Twenty-seven patients with hilar cholangiocarcinoma and eight with benign biliary dilatation were studied. All except four with hilar cholangiocarcinoma, who underwent CT using a conventional scanner, were studied with two-phase helical CT. In all patients, cholangiographs were obtained by digital fluoroscopy after the injection of contrast materials into PTBD catheters. The level of obstruction was classified according to Bismuth, and 35 CT scans were studied blindly and retrospectively by two radiologists. The findings were analyzed for the presence of tumor, and then divided into two groups (cholangiocarcinomas and benign strictures), and the positive predictive value was calculated. The CT images of klatskin tumor were analyzed with special emphasis on the level and shape of the hilar obstruction. The level of biliary obstruction and extent of the tumor were carefully correlated with the results of cholangiography. RESULTS: Thin-section spiral CT correctly identified all tumor mass as a focal wall thickening obliterating the lumen. On arterial/portal phase CT scanning, 81% of infilterative tumors showed high attenuation. In all patients, differentiation between benign stricture and klatskin tumor was possible ; correct identification of the level of obstruction and extent of tumor, according to Bismuth's classification, was possible in 63% of cases. CONCLUSION: For correct diagnosis of hilar cholangiocarcinoma and differentiation of benign stricture, helical CT was highly accurate and effective. Because of limital Z-axis resolution, however, the exact intraductalextent of the tumor was less accorately diagnosed.