Sphincter of Oddi

The sphincter of Oddi (also known as the sphincter of ampulla or choledochal sphincter) is a complex of four smooth muscle sphincters within the duodenal wall. It surrounds, and helps fix to the duodenum, the duct of Wirsung, common bile duct and the ampulla of Vater .

When relaxed it allows the passage of bile into the intestine and when contracted prevents the reflux of duodenal contents into the ducts and helps facilitates the filling of the gallbladder .

History and etymology

It is named after Ruggero Oddi (1864-1913), an Italian physiologist. The sphincter of Oddi was initially described by Francis Glisson (1597-1677) .