Sphincter of Oddi Dysfunction
The sphincter of Oddi is the muscle surrounding the end of the pancreatic and bile ducts. Its purpose is to control the flow of bile and pancreatic juice during digestion. When this muscle does not contract and relax normally, the condition is referred to as a sphincter of Oddi dysfunction. This problem may obstruct the flow of bile, resulting in pain and also obstructing the flow of pancreatic juice which, in some cases, can lead to pancreatitis. The underlying cause of this dysfunction is unknown though it has been speculated that it may result from microscopic stones in the bile duct or from duodenal inflammation.
Symptoms of Sphincter of Oddi Dysfunction
The primary symptom of sphincter of Oddi dysfunction is pain which may be experienced in the upper right quadrant of the abdomen or of the back. The pain may be worsened by eating, particularly by the ingestion of fatty foods. Opiates may bring on attacks or worsen symptoms. Symptoms are most common in female patients who have had their gallbladders removed, typically patients between 30 and 50 years of age.
Diagnosis of Sphincter of Oddi Dysfunction
There are many tests used to diagnose sphincter of Oddi dysfunction. These tests include:
- Blood tests to measure liver enzyme levels
- Blood tests to measure pancreatic enzyme levels
- Radiographic hepatobiliary scinigraphy
- Endoscopic retrograde cholangiopancreatography (ERCP)
The most definitive diagnostic test for sphincter of Oddi dysfunction is sphincter of Oddi manometry.
Treatment of Sphincter of Oddi Dysfunction
There are both medical and surgical treatments available for this condition. For some people, following a low-fat diet and taking medications is sufficient to control symptoms. Medications prescribed for sphincter of Oddi dysfunction may include antispasmodics, analgesics, or medications normally prescribed for chest pain, such as nitroglycerin and nifedipine.
More invasive treatments for this disorder include endoscopic injections of botulinum toxin (BOTOX®) and endocopic or surgical ablation of the muscle itself. Cutting of the sphincter muscle, known as a sphincterotomy, is necessary if there are stones present, there is an ongoing spasm, or scarring from previous surgery has damaged the area.