About ERCP (Endoscopic Retrograde Cholangio-Pancreatography)
What is ERCP? ERCP is an endoscopic procedure done by gastroenterology specialists. In this procedure, a side-viewing endoscope is passed through the patient's mouth, down the esophagus, through the stomach and into the duodenum. The Ampulla of Vater is visualized and X-ray dye is injected into the common bile duct and/or pancreatic duct. These two major ducts join together at the Ampulla of Vater. Part of the Ampulla of Vater is the Sphincter of Oddi, an involuntary sphincter muscle that controls the release of pancreatic enzymes and bile into the duodenum to aide in the digestion of food.
The procedure is generally done using intravenous sedation, but sometimes is done under general anesthesia. Indications for the procedure include diagnosis of cancer of the Ampulla, pancreas, or bile ducts, bile duct stone removal, evaluation of recurrent pancreatitis and pancreatic duct anomalies, and evaluation of unexplained abdominal pains.
What is ERS? ERS (Endoscopic Retrograde Sphincterotomy) is a procedure commonly described as "non-surgical" that involves cutting of the Sphincter of Oddi. This is most often done to remove stones from the CBD (Common Bile Duct) or for stenosis or abnormal narrowing of the Ampulla of Vater.
What are the complications of ERCP and ERS? The principle complication of ERCP is pancreatitis. This is a condition where the enzymes produced by the pancreas are activated and released upon the patients own tissues. This is an extremely painful condition that may run a variable course between self resolution over several days to an extremely fulminate disease process that causes respiratory failure, renal failure, hemorrhage, shock, and death. These severe cases can take months to resolve and require ICU care for weeks. Pancreatitis occurs after 10% of ERCP procedures, and develops into severe pancreatitis about 1% of the time. Doctors do not know how to prevent or modify the course of pancreatitis.
What are the alternatives to ERCP? When stones are present in the gall bladder and bile duct, LCBDE is a proven alternative that allows both removal of the gall bladder and clearing of the bile duct as a single stage procedure. This has been shown to be the least expensive and most efficacious approach to this problem. The risk of pancreatitis is much lower than with ERCP/ERS. Other alternatives to ERCP include non-invasive CT scanning and MRCP. Patients that have undergone cholecystectomy previously and have laboratory evidence of retained stones in the bile duct are probably best served by ERCP/ERS, however these problems can also be remedied via LCBDE.
What are the potential long term complications after Sphincterotomy? These are unknown at this time as ERCP/ERS has only been done in large numbers since 1990. The medical literature on surgical sphincteroplasty is worrisome, as up to 10% of these patients may develop cholangiocarcinoma (a form of cancer) after 20 - 40 years. In sphincteroplasty, the sphincter muscle has been cut and a mucosal to mucosal repair has been done. Bacteria refluxing up the biliary tree from the intestine has been hypothesized as a cause of chronic inflammation of the bile duct with the eventual development of cancer. After ERCP/ERS, the healing of the sphincter is less controlled. The Sphincter may remain open allowing this reflux of bacteria to occur. The wound may scar closed, and the sphincter may continue to function, or the scaring may be excessive, and a stenosis or narrowing of the Ampulla may be the long term outcome.
