Pancreaticobiliary long common channel syndrome and congenital anomalous dilatation of the choledochal duct--study of 46 patients.

Retrospectively evaluated clinical, radiological and anatomical findings of 46 patients with tubular or cystic dilated choledochal ducts indicate the following conclusion: Pathological stricture of the sphincter of Oddi system, including a hypertrophic and spastic portion of the sphincter choledochus inferior, called "narrow segment", raises the pressure in the choledochal duct to pathological levels and consequently causes a dilatation of the duct during a specific embryonic phase. Such a pathological sphincter of Oddi system develops if a long common channel persists as the result of a disturbance in the development of the distal choledochal and pancreatic duct. This statement contradicts the classical conception which assumes that a reflux of pancreatic juice into the choledochal duct causes ductal dilatation. Authors who are in favor of this conception propose that pancreatic juice causes weakness of the ductal wall, which may be dilated in the embryonic period. However, the findings of the series evaluated here show that dilatation of the duct may also originate without any reflux of pancreatic juice into the choledochal duct if a "narrow segment" exists above the junction of the pancreatic and choledochal ducts. For this reason, pancreatic juice reflux cannot be the condition sine qua non in the development of choledochal duct dilatation. Similarly the pathologic junction angulation can only be an optional factor in this autogenetic anomaly. With regard to a pathological sphincter of Oddi system the question arises whether a partial or complete myotomy of the muscular sphincter may be able to remedy the dilatation and avoid resection of the choledochal duct.(ABSTRACT TRUNCATED AT 250 WORDS)