What is upper endoscopy or upper GI endoscopy, esophagogastroduodenoscopy (EGD)?

Upper endoscopy is a procedure that lets us examine the lining of the upper part of your gastrointestinal tract, which includes the esophagus, stomach and duodenum (first portion of the small intestine). We use a thin, flexible tube called an endoscope, which has its own lens and light source, and will view the images on a video monitor.