A young adult evaluated for recurrent cholangitis is found on MRCP to have fusiform dilatation of both the extrahepatic bile duct and the right and left intrahepatic ducts. According to the Todani modification of the Alonso-Lej classification, this is a:

• A Type IVa choledochal cyst ✓
• B Type II choledochal cyst
• C Type III choledochal cyst
• D Type I choledochal cyst

Explanation

Todani type IVa denotes multiple cystic dilatations involving both the extrahepatic duct and the intrahepatic ducts, exactly the pattern described. Type I is dilatation confined to the extrahepatic bile duct and is the commonest variety. Type II is a true diverticulum arising from the duct, and type III is a choledochocele limited to the intraduodenal segment of the common bile duct. Type V corresponds to Caroli disease, which involves only intrahepatic ducts without extrahepatic involvement.

Reference: Sabiston Textbook of Surgery, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.