A visualising technique enabling the operator to examine the internal organs with the minimum of disturbance or damage to the tissues. The procedure has transformed the management of, for example, certain gastrointestinal and respiratory diseases.

The procedure uses a cold light source which illuminates a bundle of quartz fibres in the endoscope to demonstrate the lumen (hollow centre) of the gastrointestinal tract or the bronchi. The reflected light is returned to the observer's eye via the image bundle which may contain up to 20,000 fibres. The tip of the instrument can be angulated in both directions, and fingertip controls are provided for suction, air inflation and for water injection to clear the lens or the mucosa.

The oesophagus, stomach and duodenum can be seen; furthermore, it is also possible to look at the pancreatic and bile ducts by direct endoscopic cannulation. Fibreoptic colonoscopy can show the entire length of the colon, and it is possible both to BIOPSY polyps or suspected carcinomas and to perform polypectomy.

The fibreoptic bronchoscope can view all segmental bronchi and enable biopsy of lung tissue. Biopsy forceps can be directed well beyond the tip of the bronchoscope itself, and, being flexible, it causes less discomfort to the patient.

Fibreoptic laparoscopy is a valuable technique that allows the operator to see abdominal contents – for example, the female pelvic organs, in order to detect the presence of suspected lesions (and, in certain cases, effect their subsequent removal); to check on the development and position of the fetus; and to test the patency of the FALLOPIAN TUBES.

(See also ENDOSCOPE; BRONCHOSCOPE; LARYNGOSCOPE; LAPAROSCOPE; COLONOSCOPE.)