The Biliary System
The biliary system is composed of the organs and structures that make, store and transport bile to the duodenum (the first section of the small intestine). It includes the liver, gallbladder, pancreas and bile ducts. The liver produces bile, a yellowish green liquid that breaks down fats so they can be absorbed in the small intestine and remove waste products. Bile drains through tiny ducts into the gallbladder, where it is stored until needed during digestion.
When food leaves the stomach, the gallbladder releases stored bile to dissolve fat. The pancreas releases enzymes that travel through the pancreatic ducts and into the duodenum to breaks down the fats, as well as carbohydrates and protein.
Biliary System Problems
There are several different kinds of conditions that can affect the organs or structures in the biliary system. Gallstones are hard deposits made of cholesterol or bilirubin (a bile chemical). Often gallstones don’t cause any problems. But if a stone gets stuck in a duct, it can block the flow of bile or digestive enzymes. Symptoms of a bile duct blockage can include abdominal pain, nausea, vomiting and jaundice (yellowish coloring of the skin and eyes). Sometimes a stone becomes caught in the pancreatic duct, causing an inflammation of the pancreas. Pain associated with gallstone pancreatitis can occur suddenly and be severe. Gallstones occur more often in women than in men and are most common in people over 60.
Cancer can also occur in any part of the biliary system. According to the American Cancer Society, about 2,000 to 3,000 cases of bile duct cancer occur every year in the U.S. Most patients are over 65 at the time of diagnosis.
Diagnosing and Treating Biliary Tract Conditions
When biliary tract disease is suspected, doctors may perform imaging procedures, such as ultrasound, CT scan or MRI. Owen Maat, M.D., Gastroenterologist with Memorial Hermann Southwest in Houston, TX, says although these technologies have improved over the past several years, there are still areas that can’t be seen with standard imaging techniques. In endoscopic retrograde cholangiopancreatography (ERCP), doctors use a lighted viewing instrument, called an endoscope. With the patient under sedation, the endoscope is inserted into the mouth and fed down the throat, then into the stomach and small intestine. A dye is placed into the bile ducts to provide better visualization from a camera on the end of the endoscope. If a gallstone is detected, it can be picked up by tiny forceps, placed into a basket and removed from the body.
ERCP is still not perfect. Sometimes stones can’t be seen and not all parts of the biliary tract are accessible with the standard endoscopes. In addition, standard endoscopes are difficult to maneuver. Experts also say conventional ERCP requires two physicians, one to operate the viewing endoscope and one to operate the therapeutic endoscope.
The SpyGlass® Direct Visualization System
Scientists have developed a new tool for imaging the biliary tract, called the SpyGlass® Direct Visualization System. The SpyGlass uses a mini-endoscope that has four-way maneuverability. It also uses a miniature 6,000 pixel fiber-optic probe that transmits images from inside the biliary tract.
Maat explains the SpyGlass is used like a traditional endoscope. However, because it is easy to maneuver, only one physician is needed to operate the system. It can reach areas of the biliary tract that are inaccessible with standard endoscopes. In addition, extra channels in the device enable the physician to insert instruments to deliver treatment from inside the body. Maat says one instrument can deliver sound waves that break up gallstones so they can be more easily removed. Another instrument enables a physician to take biopsies of tissue suspected to be cancer.
The SpyGlass is typically done as an outpatient procedure and patients are out of the hospital in just a few hours.
AUDIENCE INQUIRYFor information about the SpyGlass® Direct Visualization System, go to http://www.bostonscientific.com
For general information on conditions affecting the biliary tract:
American College of Gastroenterology, http://www.acg.gi.org/patients/gihealth/biliary.asp
National Institute of Diabetes and Digestive and Kidney Diseases, http://www.niddk.nih.gov
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Chen, Y., and D. Pleskow, “SpyGlass Single-Operator Peroral Cholangiopancreatoscopy System for the Diagnosis and Therapy of Bile-Duct Disorders,” Gastrointestinal Endoscopy, May 2007, Vol. 65, No. 6, pp. 832-841.
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