MRI findings in Caroli's disease and intrahepatic pigmented calculi.

This paper reports a case of Caroli's disease confined to the left lobe of the liver that mimicked left portal vein thrombosis on MRI studies because of the very high signal intensity on T1-weighted images of intrahepatic pigmented calculi. The preoperative diagnosis was a cholangiocarcinoma infiltrating the left hepatic bile duct and portal branch. The final macroscopic and histological diagnosis was Caroli's disease of the left liver lobe with wide enlarged left bile duct containing multiple pigmented calculi.