Cholangiographic demonstration of relief of narcotic-induced spasm of the sphincter of Oddi.

Narcotics are known to cause spasm of the sphincter of Oddi. This spasm may be difficult to distinguish from obstruction of the distal common bile duct on operative cholangiograms in cases where narcotics are used perioperatively. A case is presented in which narcotic-induced spasm of the sphincter of Oddi, clearly demonstrated in an operative cholangiogram, is reversed by a narcotic antagonist, thereby avoiding an unnecessary common duct exploration.