Dysfunction of the sphincter of Oddi is assuming increasing importance because of its relationship to the painful sequelae which at times follow cholecystectomy and because of its possible etiologic significance in the production of pancreatitis. Information concerning the innervation of the sphincter of Oddi should be helpful in understanding its function and dysfunction.
In 1923 Westphal11 described a choledochal sphincter made up of circular and oblique muscle fibers commencing just outside of the duodenal wall and continuing almost to the tip of the papilla of Vater. The tip of the papilla, he noted, was encircled by a separate iris-like circular muscle bundle, which he called the papillary sphincter. Weak electrical stimulation of the vagus nerve in the abdomen produced relaxation of the sphincter of Oddi, whereas strong vagal stimulation produced spasm of the choledochal portion of the sphincter. Sympathetic stimulation caused a relaxation of the choledochal sphincter and contraction