Pancreatic bladder or double gallbladder draining into pancreatic duct?

We report a case of pancreatic bladder which could also be interpreted as double gallbladder draining into the pancreatic duct. A 6-year-old Japanese boy underwent a cholecystectomy of the smaller bladder under the diagnosis of duplication of the gallbladder, leaving the normal gallbladder and an unremarkable biliary ductal system. The smaller bladder was histologically similar to the gallbladder tissue. At age 25, relaparotomy was performed. It was confirmed that the residual aberrant duct from the smaller bladder joined directly with the duct of Wirsung and that the patient had fusiform dilatation of the extrahepatic bile duct. The extrahepatic portion of the bile duct was excised along with the "normal" gallbladder and the residual aberrant duct. The present anomaly seems to validate the designation of pancreatic bladder whose cystic duct joined directly with the pancreatic duct, but may also be explained from the view point of double gallbladder.