Which choledochal cyst type is dilation of the intrahepatic ducts only (Caroli disease)?

Which choledochal cyst type is dilation of the intrahepatic ducts only (Caroli disease)?

• A. Type V
• B. Type II
• C. Type III
• D. Type IV

Answer: (A)

Dilation confined to the intrahepatic bile ducts defines Caroli disease. In the choledochal cyst classification, this intrahepatic pattern is the type associated with Caroli disease, where the ducts within the liver are enlarged while the extrahepatic ducts remain normal. On imaging, you’ll see multiple saccular dilatations of the intrahepatic ducts, and MRCP or CT may show a central dot sign (portal radicles surrounded by dilated ducts). Caroli disease can occur on its own or as Caroli syndrome when it’s associated with congenital hepatic fibrosis and other kidney anomalies. This pattern is distinct from other types that involve the common bile duct or extrahepatic portions or multiple ducts beyond the liver.

Dilation confined to the intrahepatic bile ducts defines Caroli disease. In the choledochal cyst classification, this intrahepatic pattern is the type associated with Caroli disease, where the ducts within the liver are enlarged while the extrahepatic ducts remain normal. On imaging, you’ll see multiple saccular dilatations of the intrahepatic ducts, and MRCP or CT may show a central dot sign (portal radicles surrounded by dilated ducts). Caroli disease can occur on its own or as Caroli syndrome when it’s associated with congenital hepatic fibrosis and other kidney anomalies. This pattern is distinct from other types that involve the common bile duct or extrahepatic portions or multiple ducts beyond the liver.