Endoscopy

[Sarah]

The art or process of examining by means of the endoscope.

[Luis Fok]

Endoscopy is an examination of internal structures using a flexible viewing tube (endoscope). Endoscopy can also be used to treat many disorders because doctors are able to pass instruments through the tube.
When passed through the mouth, an endoscope can be used to examine the esophagus (esophagoscopy), the stomach (gastroscopy), and part of the small intestine (upper gastrointestinal endoscopy). People who are having endoscopy of the upper parts of the digestive tract may be given a liquid or spray anesthetic to numb their throat before the procedure.
When passed through the anus, an endoscope can be used to examine the rectum (anoscopy); the lower portion of the large intestine, the rectum, and the anus (sigmoidoscopy); and the entire large intestine, the rectum, and the anus (colonoscopy). For procedures other than anoscopy and sigmoidoscopy, people are typically given drugs by vein (intravenously) to calm them and prevent discomfort (sedation).
Endoscopes range in diameter from about

[Oralee]

A procedure in which an instrument is introduced into the body to give a view of its internal parts.

[Mary Mallozziberg]

a medical examination of a hollow organ of the body