Isolated cystic dilatation of the cystic duct.

Presented was an unusual case of congenital cystic dilatation of the extrahepatic biliary tract in which the cystic changes were confined solely to the cystic duct. There was concomitant common bile duct obstruction secondary to inflammation and mass effect from the cyst. Management consisted of cholecystectomy, excision of the cyst, common bile duct exploration, examination of the ampullary region by duodenotomy, and choledochoduodenostomy.