Endoscopic Retrograde Cholangiopancreatography

Endoscopic retrograde cholangiopancreatography (ERCP) is endoscopy of the biliary tree and the pancreatic duct. By injection of contrast media, a retrograde image of both structures can be formed on X-ray, facilitating the diagnosis of obstruction, e.g. by gallstones or cholangiocarcinoma.

The patient is often sedated or anesthetized. Then a flexible camera (endoscope) is inserted through the mouth, down the esophagus, into the stomach, through the pylorus into the duodenum where the ampulla of Vater (the opening of the common bile duct) exists. The sphincter of Oddi is a muscular valve that controls the opening of the ampulla. The region can be directly visualized with the endoscopic camera while various procedures are performed. A plastic catheter or cannulatome is inserted through the ampulla, and radiocontrast is injected into the bile ducts, and/or, pancreatic duct. Fluoroscopy is used to look for blockages, or leakage of bile into the peritoneum (the abdominal cavity).

A wire and balloon may be passed into the bile duct, then inflated in order to expand the opening of the bile duct to allow passage of gallstones. Occasionally, an electric cauterizer will be used to cut the sphincter opening, making it wider.

Other procedures associated with ERCP include the trawling of the common bile duct with a basket or balloon to remove gallstones and the insertion of a plastic stent to assist the drainage of bile.

Potential complications include acute pancreatitis and perforation.