An anti-reflux valve developed to help esophageal cancer patients also has been shown to help those with bile duct obstruction, according to Kulwinder S. Dua, M.D., a research physician at the Medical College of Wisconsin in Milwaukee. The study, using the anti-reflux biliary stent in patients with cancer of the pancreas or bile duct, appears in the May issue of Gastrointestinal Endoscopy journal.
This bile duct stent with the "Dua Anti-Reflux Valve," named after its inventor, was cleared for use by FDA last year. The Dua stent, for short, has also been approved for use in Europe and Canada.
The bile duct carries bile from the liver to the intestines. When this duct is obstructed from cancers of the pancreas, gallbladder, or bile duct, bile begins to backup resulting in jaundice, itching, fever, chills, other organ malfunctions and death. About 30,000 new patients with pancreatic cancer and 4,000 new cases of bile duct cancer are diagnosed in the United States each year, most frequently in older people.
Surgery to remove the tumors is generally the best treatment, but often the disease has progressed too far to consider surgery. Consequently, a stent, a tiny, hollow tube, is inserted using a minimally invasive procedure to help improve the passage of bile. However, these stents frequently clog requiring repeat procedures to replace the clogged stents. The exact mechanism that leads to stent clogging is not known. There is a possibility that clogging occurs from contents from the intestines backflowing (refluxing) into the stent.
The "Dua Anti-Reflux Valve" was initially developed to reduce reflux of stomach contents in patients with cancers of the esophagus. Resembling a windsock, it functions as a pressure-sensitive valve that closes when stomach pressure increases thereby preventing reflux. However, when the pressure builds beyond a certain point, the valve inverts allowing for belching or vomiting. By drinking one gulp of water, it
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Medical College of Wisconsin