The sphincter of Oddi (SO) is a muscular structure that encompasses the confluence of the distal common bile duct and the pancreatic duct as they penetrate the wall of the duodenum (figure 1). The term "sphincter of Oddi dysfunction" has been used to describe a clinical syndrome of biliary or pancreatic obstruction related to mechanical or functional abnormalities of the sphincter of Oddi. The terms papillary stenosis, sclerosing papillitis, biliary spasm, biliary dyskinesia, and postcholecystectomy syndrome have been used synonymously.
The treatment of sphincter of Oddi dysfunction (SOD) will be reviewed here. The clinical manifestations and diagnosis of this disorder are discussed separately. (See "Clinical manifestations and diagnosis of sphincter of Oddi dysfunction".)
Few studies have addressed the long-term natural history of SOD. The available data suggest that the clinical course is variable depending in part upon the initial biliary classification. (See "Clinical manifestations and diagnosis of sphincter of Oddi dysfunction", section on 'Classification systems'.)
In a one-year follow-up study, seven type II patients (biliary pain and either abnormal liver tests or a dilated common bile duct) with abnormal SO pressure treated by a sham procedure continued to have symptoms, which resolved only after subsequent sphincterotomy. All patients continued to do well four years later. Five other type II patients with abnormal SO pressure refused sphincterotomy. At four-year follow-up, three were unimproved, while two had "fair" improvement.
The clinical course is unpredictable after a sham or endoscopic sphincterotomy in patients with type III biliary pain (biliary pain but normal liver tests and common bile duct). In one report, 11 such patients were followed for two years after sphincterotomy. Four improved symptomatically while seven had no change. Eleven other patients had a sham procedure, of whom five improved, while six had no change in symptoms during two years of follow-up .