Weekly issue 2026-W39 ·
Congenital biliary abnormalities in adults: a practical CT and MRI guide
Plain language
This radiology guide explains how CT and MRI scans tell apart bile-duct conditions people are born with, including the liver cysts of polycystic liver disease and Caroli disease, which can occur with recessive PKD (ARPKD). The cysts of polycystic liver disease do not connect to the bile ducts and carry very little cancer risk, while some other bile-duct malformations need closer watching. Knowing which condition you have shapes how often you need scans.
Clinical note
Narrative imaging review in four categories: congenital cystic biliary dilatation, fibropolycystic disorders from ductal plate malformation (Caroli, PLD), anatomical variants, rare anomalies. MRCP is the cornerstone; CT for complications. Key signs: Caroli central dot, diffuse non-communicating cysts in PLD, long common channel in pancreaticobiliary maljunction. Malignant potential negligible in PLD vs substantially increased in choledochal cyst/maljunction (estimates from heterogeneous retrospective series). Includes a diagnostic algorithm and structured reporting checklist.
Question for your next visit
Do my liver cysts connect to the bile ducts, and does that change how often I need scans?