Endoscopic Retrograde Cholangio-Pancreatography (ERCP) is a technique that combines the use of endoscopy and fluoroscopy to diagnose and treat certain problems of the biliary or pancreatic ductal systems. Through the endoscope, the physician can see the inside of the stomach and duodenum, and inject radiographic contrast into the ducts in the biliary tree and pancreas so they can be seen on X-rays.
ERCP is used primarily to diagnose and treat conditions of the bile ducts and main pancreatic duct, including gallstones, inflammatory strictures (scars), leaks (from trauma and surgery), and cancer. ERCP can be performed for diagnostic and therapeutic reasons.
The patient is sedated or anaesthetized. 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 and pancreatic 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 cannula 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 other lesions such as stones.
When needed, the opening of the ampulla can be enlarged (sphincterotomy) with an electrified wire (sphincterotome) and access into the bile duct obtained so that gallstones may be removed or other therapy performed. 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. Also, the pancreatic duct can be cannulated and stents be inserted. The pancreatic duct requires visualisation in cases of pancreatitis.
The major risk of an ERCP is the development of pancreatitis, which can occur in up to 5% of all procedures. This may be self limited and mild, but may require hospitalization, and rarely, may be life-threatening. Patients at additional risk for pancreatitis are younger patients, patients with previous post-ERCP pancreatitis, females, procedures that involve cannulation or injection of the pancreatic duct, and patients with sphincter of Oddi dysfunction.
Oversedation can result in dangerously low blood pressure, respiratory depression, nausea, and vomiting. There is also a risk associated with the contrast dye in patients who are allergic to compounds containing iodine. Other complications (less than 1 per 10,000) may include; heart and lung problems, bleeding after sphincterotomy, infection in the bile duct (cholangitis) and perforation (a tear in the intestine).