Laparoscopic anatomy of the biliary tree.

A thorough knowledge of the anatomy of the extrahepatic biliary tree and its frequent anatomic variations is essential for performance of a safe laparoscopic cholecystectomy. The surgeon should have an appreciation for the distortions in the anatomy as a result of retraction on the gallbladder and how the direction of retraction alters the spatial relationships between the cystic duct and common bile duct. The steps in the operative procedure have been outlined to provide good exposure and optimize the identification of structures. Good exposure will enable the surgeon to identify anatomic variants; however, a thorough knowledge of these variants is necessary for safe performance of the operation.