Adult type I choledochal cyst resection.
Type I choledochal cysts are characterized by fusiform dilatation of the common bile duct, commonly associated with an anomalous pancreatobiliary duct junction. Most are diagnosed in childhood, but the diagnosis may be delayed until adulthood. All type I choledochal cysts should be resected because of the risk of malignant degeneration. The steps for resecting a type I choledochal cyst are described. Through a right subcostal incision, the cyst is exposed and transected distally as it narrows within the pancreatic parenchyma. A total transmural excision of the extrahepatic biliary tree is performed. A retrocolic Roux-en-Y hepaticojejunostomy restores biliary-enteric continuity. Thirty-day mortality is low and long-term outcomes are excellent.