Etiology relationship and principles of treatment of pancreatic and biliary anomalous junction and choledochal cyst        LI Long, ZHANG Jin-shan. Pediatrics Surgery of Capital Institute, Beijing 100020, China
Corresponding author: LI Long, E-mail：zjs851@163.com
Abstract    Choledochal cyst (CC) is a pathologic condition characterized by varying degrees of congenital dilatation of the biliary system. Most of the reported cases come from Asia and its etiology remains unclear. Some people suggested that CC is a result of weakness of the wall and the distal obstruction of the common bile duct. But its underlying precise mechanisms remain unclear. The pathogenetic implications of pancreaticobiliary maljunction (PBM) is a popular hypothesis: In PBM, the common channel can be so long that the junction of the pancreatic and bile ducts is located outside of the duodenal wall; in such cases, sphincter action does not functionally affect the junction. As the hydropressure within the pancreatic duct is usually greater than in the bile duct, pancreatic juice frequently refluxes into the biliary duct (pancreatobiliary reflux) in PBM, resulting in the incidence of lesion in the wall of the common bile duct and dilatation of the common bile duct. Currently, most scholars tend to believe the ectopic hepatic diverticulum may cause the primitive common bile duct and common channel to become stretched, producing a long common bile duct and a long common channel. If growth of the epithelium in the common bile duct fails to keep up with the anomalous elongation during embryonic, the duct may become attenuated, resulting in stenosis and weakness of the wall, and eventually dilatation. In treatment, the cyst excision with Roux-en-Y hepatoenterostomy is the standard surgical method for choledochal cyst. To reduce the post-operative complications, doctors need to learn about the changes of the biliary system, deal with the abnormality in the intrahepatic bile duct, pancreatic duct and common channel. Laparoscopic surgery has become a successful method in treatment of choledochal cyst.