An endoscopy is a medical procedure where a thin hollow metal tube with a light and camera on one end is inserted into the stomach through the mouth, throat and esophagus to allow the stomach lining to be examined visually by a physician. In addition, instruments can be inserted through the tube to allow the physician to perform medical procedures such as cauterization.
Endoscopy is considered to be an invasive medical procedure. It can be done without anesthetic. As a result, many medical tests have been developed to avoid endoscopy, such as the Carbon-14 test for gastric ulcers.
However, in cases of gastric bleeding, an emergency endoscopy must usually be performed as the condition can lead to severe complications.