Pancreatico-biliary ductal union.

A long common channel distal to the pancreaticobiliary junction is the commonest anomalous arrangement of the pancreaticobiliary ductal system and is mostly observed in patients with congenital choledochal cysts. APBDU without choledochal cyst is a high-risk condition for the development of gallbladder carcinomas. Prophylactic excision of the extrahepatic biliary system and reconstruction of the biliary tract with hepatico-jejunostomy are recommended. APBDU should always be kept in mind when a patient with a long history of abdominal pain is found to have gall bladder wall thickness even without gallstones on imaging by a CT Scan or Ultra Sound. ERCP should be performed in these patients in order to detect APBDU. This may allow early detection of carcinoma of the biliary tract. Presence of common channel may be associated with a lower incidence of gallstones. However it requires corroboration by other studies. On the other hand carcinoma of the gall bladder appears to have a close association with abnormally long common channel.