Advanced Endoscopy Clinical Care

Sphincterotomy is a medical procedure that cuts the muscular sphincter of the bile duct or pancreatic duct. A sphincterotomy is usually performed to assist in bile duct stone removal prior to placement of a stent or drainage tube to treat papillary stenosis and sphincter of Oddi dysfunction and to facilitate stricture dilation and tissue sampling. A small incision (about ¼ – ½ inch long) is made in the papilla to expand the relevant opening. This incision is made with an electrical current that also cauterizes the tissues to prevent bleeding. A special type of sphincterotomy, a precut sphincterotomy, is used as a last resort when a physician experiences difficulty in trying to place the standard sphincterotome completely into the pertinent duct. This type of treatment is deemed somewhat more risky in certain situations.

After successful dilation of a duct narrowing, a physician may insert a small tube called a stent to keep the duct expanded or to aid with any duct drainage. There are plastic (polyethylene) stents and metal (metallic) stents. A plastic stent is most commonly used. Plastic stents are generally trouble-free; however, they tend to clog up, thus requiring an additional ERCP in order to remove the stent and replace it with a fresh stent. This type of stent is easy to use and can pass out of the body on its own through stool, or it may require removal by a physician via another ERCP. Metal stents are permanent and expand to a larger diameter once in place. If this type of stent becomes clogged, a plastic or another metal stent can be placed through the original stent. In expert hands, stent placement is very successful.

Stone removal is performed when stones are detected. The most common type of stone requiring removal is bile duct stone. Prior to stone removal, a biliary sphincterotomy (an incision is made to expand the opening of the bile duct) is usually performed. Once the incision is made, a physician can remove the stones with a special “basket” designed for stone removal or (s)he may manipulate the stone by using an inflatable balloon device designed to sweep the duct. Stones sometimes pass (into the duodenum) spontaneously after a sphincterotomy is performed; however, physicians generally attempt removal. Larger stones may need to be crushed before a removal attempt can be successful. This type of procedural technique is called a mechanical lithotripsy. Stones detected in the pancreatic ducts can be successfully removed; however, this type of stone removal is technically more complex.

A partial blockage or narrowing of the bile or pancreatic duct can be treated with hydrostatic balloon dilation (similar to that used in the arteries of the heart) during the ERCP procedure. The balloon is used to stretch and expand the duct. Dilation may also be achieved by using a graduated catheter passed over a guidewire.

Pancreatitis is the most common side effect of an ERCP. It occurs in 10 percent of ERCPs and generally requires hospital admission and generally settles in one to three days in almost all cases. The treatment for mild pancreatitis usually consists of restriction of oral intake to ice chips, intravenous fluids and analgesics (pain medications) as needed. Severe pancreatic damage can result in the formation of pseudocyst or abcesses, which may require a prolonged hospital stay. This occurs in less than one percent of patients. It can occur even in the most expert hands.

Other important complications can occur after treatments such as sphincterotomy. A sphincterotomy can trigger bleeding, which can be controlled by the doctor during the ERCP. It is rare and uncommon for a blood transfusion to be needed. Sphincterotomy may result in a perforation when the cut extends into the tissues behind the duodenum and pancreas. Most perforations can be treated medically (with IV fluids, antibiotics and nasogastric tube). In severe cases, it may require surgery. On very rare occasions, the endoscope itself can cause a perforation (make a hole). This type of perforation usually requires surgical treatment.

Infection can occur in the bile ducts or pancreas after ERCP, especially when there is duct obstruction that cannot be treated by the ERCP procedure. Antibiotics are required and possibly another type of drainage procedure such as surgery.

The fluoroscope involves a small dose of radiation; this is no greater exposure than any other standard x-ray test and is well within the recommended limits. Possible drug reactions could occur with the medications and can cause nausea and skin reactions. About one percent of ERCP procedures can result in severe complication. These types of complications would require a prolonged hospital stay, treatment in an intensive care unit or surgery. Death rarely occurs.