Source:http://linkedlifedata.com/resource/umls/id/C0028872
MSH: The sphincter of the hepatopancreatic ampulla within the duodenal papilla. The COMMON BILE DUCT and main pancreatic duct pass through this sphincter.,NCI: The muscle fibres around the opening of the common bile duct (ductus choledochus) into the duodenum at the papilla of Vater.