A visualizing technique enabling the operator to examine the internal organs with a minimum of disturbance or damage to bodily tissues.

This procedure has transformed the management of, for example, gastrointestinal diseases.

In chest disease, fiberoptic bronchoscopy has now replaced the rigid wide-bore metal tube which was previously used for examination of the tracheo-bronchial tree.

Fiberoptic colonoscopy can visualize the entire length of the colon and it is now possible to biopsy polyps (any mass of tissue that bulges or projects outward or upward from a normal body surface level), or suspected carcinomas, and to perform polypectomy (surgical removal of a polyp).