Upper gastrointestinal (UGI) endoscopy is a test that allows the
doctor to look at the interior lining of the upper digestive tract (the
esophagus, stomach, and upper end of the small intestine) through a thin,
flexible viewing instrument called an endoscope. The tip of the endoscope is
inserted through the mouth and then gently advanced down the throat into the
esophagus, stomach, and upper small intestine (duodenum).
Through the endoscope, the doctor can look for ulcers,
inflammation, tumors, infection, or bleeding. Tissue samples can be collected
(for biopsy), polyps can be removed, and bleeding can be treated through the
endoscope. Endoscopy can reveal problems that do not show up on X-ray tests and
can sometimes eliminate the need for exploratory surgery.