Endoscopy

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Endoscopy, examination of internal body cavities using a specialized medical instrument called an endoscope. Physicians use endoscopy to diagnose, monitor, and surgically treat various medical problems.

An endoscope is a slender, flexible tube equipped with lenses and a light source. It contains glass fibers that transmit light to illuminate the body part being viewed and fibers that reflect an image of the body part back to the viewer. The endoscope also has a channel through which surgeons can manipulate tiny instruments, such as forceps, surgical scissors, and suction devices. A surgeon introduces the endoscope into the body either through a body opening, such as the mouth or the anus, or through a small incision in the skin.

During the endoscopic procedure, the surgeon may perform several tasks. The surgeon may look for visual evidence of the problem, such as ulceration or inflammation; collect a sample of tissue; remove problematic tissue, such as polyps; or photograph the area being examined. Most endoscopic procedures are normally done with the patient lightly anesthetized.

The term endoscopy is both a general and a specialized term. As a specialized term it refers to endoscopic examination of the gastrointestinal tract. As a generalized term, endoscopy refers to examination of a wide variety of body parts. Depending on the body part, each type of endoscopy has its own special term, such as laparoscopy (abdomen), laryngoscopy (vocal cords), bronchoscopy (lungs), colonoscopy (colon), and arthroscopy (joint).

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