Magnetic Resonance Imaging Findings of Portal Biliopathy

ABSTRACT

PURPOSE: We wanted to evaluate the MR imaging findings of portal biliopathy. MATERIALS AND METHODS: We retrospectively reviewed the MR imaging of twelve patients having biliary abnormalities and portal cavernoma. Two radiologists working in consensus analyzed the presence of extrahepatic portal vein obstruction, cavernous transformation, portosystemic collaterals and bile ducts abnormalities that included irregular contour, stricture, ductal dilatation, wall thickening and enhancement of the ductal wall. RESULTS: Extrahepatic portal vein obstruction was replaced by cavernous transformations in all patients. The cavernous transformations depicted on the MR scans were paracholedochal veins in 12 patients and epicholedochal veins in 6 patients. Three different types of biliary abnormalities were present 1) the pseudocholangiocarcinoma type (3 patients) that resembled extrahepatic cholangiocarcinoma, 2) the varicoid type (6 patients) that was mainly distinguished by the multiple smooth extrinsic impressions along the common bile duct and 3) the mixed type (3 patients). The highly specific findings for the pseudocholangiocarcinoma type disease were thickening and delayed enhancement of the biliary ductal wall. CONCLUSION: The MR findings of portal biliopathy include cavernous transformation of the portal vein and morphological alterations of the biliary tracts such as irregular contour, biliary stricture with proximal ductal dilatation and thickening of the ductal wall with delayed enhancement. Recognition of these MR findings should facilitate the accurate diagnosis of portal biliopathy and prevent the misinterpretation or inappropriate management of this disease as malignancy or sclerosing chloangitis.