[Function of the accessory pancreatic duct in the pancreaticobiliary maljunction].

We examined the function of the accessory pancreatic duct (APD) in 56 cases of the pancreaticobiliary maljunction. APD existed in 11 of 26 cases of the congenital choledochal cyst. The maximal diameter of APD was over 2 mm in 5 cases. Patency of APD was detected in 5 of 9 cases examined by dye-injection endoscopic retrograde pancreatography (ERP). APD existed in 15 of 30 cases of the pancreaticobiliary maljunction without biliary dilatation, and all APDs were less 2 mm in diameter. By dye-injection ERP, APD was patent in 4 of 13 cases. There was no significant relationship between patency of APD and associated biliary carcinoma in the cases of the pancreaticobiliary maljunction, but 5 cases of the congenital choledochal cyst with APD bigger than 2 mm in diameter had no biliary carcinoma. Amylase level of the bile in cases of the pancreaticobiliary maljunction with patent APD was frequently lower than that of cases with nonpatent APD. It is suggested that in cases of the pancreaticobiliary maljunction with patent APD, the incidence of carcinogenesis of the biliary tract might be lower, as the reflux of the pancreatic juice to the bile duct might be reduced by the flow of pancreatic juice from the upper dorsal pancreatic duct into the duodenum via the minor duodenal papilla.