Upper endoscopy enables
the physician to look inside the esophagus, stomach and duodenum (first part of
the small intestine). The procedure might be used to discover the reason for
swallowing difficulties, nausea, vomiting, reflux, bleeding, infection, tumors,
indigestion, abdominal pain or chest pain. Upper endoscopy is also called EGD,
which stands for esophagogastroduodenoscopy.