Recent advances in pathophysiology and surgical treatment of congenital dilatation of the bile duct.

The introduction of the concept of pancreaticobiliary maljunction (PBM) has led to significant progress in the pathogenetic study and surgical treatment of congenital dilatation of the bile duct (CDBD). Clinical studies of 155 patients with CDBD, and basic experimental studies of the mechanisms of bile duct dilatation and associated pancreatitis were conducted. The CDBD was morphologically classified as either cystic or cylindrical type. Clinical signs, symptoms, and laboratory findings were highly dependent on two factors: the age at onset and the reflux of pancreatic juice into the bile duct through the PBM. The canine experimental model of PBM exhibited not only significant bile duct dilatation but also morphological findings similar to those in the CDBD patients. Subsequent studies in a rat model clarified the involvement of activated pancreatic enzyme phospholipase A(2) in PBM-associated pancreatitis. For surgical treatment, cystoenterostomy has been superseded by hepatico-enterostomy after removal of the damaged bile ducts and blocking their communication with the pancreatic duct. Long-term follow-up studies have shown excellent results by confirming the surgical correction based on the pathological principles. Regarding biliary reconstruction, jejunal interposition hepatico-duodenostomy, which is, theoretically, a logical approach was unexpectedly shown to often lead to bile reflux gastritis, so it is now superseded by Roux-en-Y hepaticojejunostomy.