fiberoptic duodenoscope, an instrument for visualizing the interior of the duodenum, consisting of an eyepiece, a flexible tube incorporating bundles of coated glass or plastic fibers with special optic properties, and a terminal light. When the duodenoscope is introduced into the patient’s mouth and threaded through the upper digestive tract to the duodenum, the light illuminates the internal structures and any lesions present, and the fiberoptic bundles transmit the image to the observer’s eyepiece.
