Intrahepatic bile duct stenosis causing intrahepatic calculi formation following excision of a choledochal cyst.

Formation of intrahepatic calculi is one of the major late complications after excision of a choledochal cyst. There are few studies, however, that have examined this complication. Generally, an anastomotic stricture is believed to be the main cause of intrahepatic calculi. We report our experience with eight patients who had intrahepatic calculi after excision of a choledochal cyst.To determine what caused the intrahepatic calculi to form, seven patients underwent cholangioscopy and direct visual inspection during the operation, and one patient underwent percutaneous transhepatic cholangioscopy. Intrahepatic bile was cultured, and calculi were analyzed.Two types of stenoses (membranous and septal) were demonstrated near the hepatic hilum in all patients. Calculi were always located on the hepatic side of the stenoses. No anastomotic strictures were found in the region of the hepaticojejunostomy. The calculi contained mainly calcium bilirubinate. Escherichia coli and Klebsiella pneumoniae were cultured from the bile in all patients.Stenoses of the intrahepatic bile ducts were demonstrated in all eight patients. The stenoses were considered to be the primary cause of intrahepatic calculi formation after excision of the choledochal cysts.