What Is a Biliary Endoscopic Sphincterotomy?

A sphincterotomy is a complex procedure that involves the use of an endoscope (a long, thin, flexible tube that has a light and camera at one end) and imaging techniques to manipulate the sphincter of Oddi. 

A biliary endoscopic sphincterotomy removes gallstones and bile duct blockages.

A biliary endoscopic sphincterotomy is a procedure that cuts the muscle (sphincter) between the common bile duct and pancreatic duct. This procedure uses a catheter (flexible tube) and wire to remove gallstones or any other blockages.

The most common use of a biliary endoscopic sphincterotomy is removing blockages in the bile ductular system. Below are a few common conditions where a biliary endoscopic sphincterotomy is performed:

• Removal of common bile duct (CBD) stones
• Treatment of papillary stenosis or sphincter of Oddi dysfunction (bile obstruction)
• Stent placement
• Tissue sampling

Patients with the following conditions are not recommended to undergo a biliary endoscopic sphincterotomy:

• Heart disease such as myocardial infarction
• Severe lung disease such as severe cardiopulmonary disease
• Acute pancreatitis (swelling in the pancreas). 
• Dye allergies
• Abnormal blood conditions such as uncorrected severe coagulopathy or thrombocytopenia (bleeding disorders)

However, patients having swelling in the pancreas due to bile obstruction can be considered for this procedure.

The sphincter of Oddi refers to the smooth muscle that surrounds the terminal portion of the common bile duct and pancreatic duct. This muscle relaxes during a meal to allow bile and pancreatic juices to flow into the intestine. 

Sphincter of Oddi dysfunction refers to the medical condition in which the sphincter (smooth muscle) loses its ability to contract and relax in a normal fashion. This may obstruct bile flow resulting in biliary pain and obstruction of the flow of pancreatic juice, leading to pancreatitis. 

The cause of this dysfunction is unknown; however, several theories suggest that the presence of microscopic stones in the bile and duodenal (part of the intestine) swelling could be the causes of this dysfunction. 

The most common symptom of this dysfunction is recurrent steady pain in the abdominal upper right area. 

• This pain may worsen after meals, particularly after fatty foods. 
• Medications such as opiates may also worsen the pain. 
• Patients may present with recurrent persistent pain after gallbladder removal. 
• Patients with sphincter of Oddi dysfunction may require a biliary endoscopic sphincterotomy for long-term pain relief.

A biliary endoscopic sphincterotomy is performed under general anesthesia. The surgeon passes a thin instrument into the area of the small intestine where the sphincter of Oddi is located and cuts the muscle. The surgeon will ensure that there are no stones in the gallbladder.

• After the patient is given anesthesia, vitals are monitored throughout the procedure.
• In this procedure, the surgeon passes a cannula (flexible tube) to the bile duct through the papilla of Vater (an organ in the small intestine) using an electrocautery sphincterotome (a surgical instrument that has a metal wire covered by an insulating sheath, with the 20-30 mm of wire exposed, and a short radio-opaque, tapered tip for passing current).
• The surgeon makes a small cut measuring approximately 1 cm through the sphincter of Oddi and on the duodenal portion of the common bile duct, creating an opening from which bile can flow. Through the same opening, the surgeon removes the microscopic stones as well.

Endoscopic sphincterotomy complications are related either to the drugs used during the procedure or to the results of dye injection or cutting of tissue.

• Anesthesia risks such as headache, vomiting, and drowsiness
• Perforation during surgery
• Inflammation of the pancreas is the most common complication.
• Inflammation of cholangitis (bile ducts)
• Bacteremia (the passage of bacteria into the bloodstream)
• Severe bleeding

In most cases, a biliary endoscopic sphincterotomy can provide a good relief from pain and other symptoms of dysfunction. However, this procedure is usually considered only after the medical treatment has failed. 

A biliary endoscopic sphincterotomy is a difficult procedure that has a fairly high risk of complications. Approximately 5%-15% of patients develop complications such as swelling of the pancreas, but in some cases, the complications are severe and may require a long stay in the hospital. 

According to studies, the overall success rate of this procedure is 70%.