The sphincter of Oddi is the muscular valve surrounding the exit of the bile duct and pancreatic duct into the duodenum , at the papilla of Vater. The sphincter is normally closed, opening only in response to a meal so that digestive juices can enter the duodenum and mix with the food for digestion. When the hole is too tight, there is a backup of bile and pancreatic juices. Also, blockage to the pancreatic orifice can cause pancreatic pain or attacks of pancreatitis . This can be recognized by scans and various x-rays, including ERCP .
Papillary stenosis requires endoscopic or surgical treatment.
The hole is enlarged by cutting, to improve drainage. This is a more difficult problem. However, in some patients, it is the prevailing complaint, and requires focal attention. The pain symptoms are very similar to those caused by bile duct or gallbladder stones. Some patients present with unexplained attacks of acute pancreatitis when the pancreatic sphincter is involved predominantly.