A series of X-ray studies of the esophagus, stomach, and small bowel; done after the patient swallows barium contrast medium to outline the parts to be studied.
A series of X rays using the contrast medium barium. An upper Gl series uses X rays to diagnose problems in the esophagus, stomach, and duodenum (the first part of the small intestine into which the stomach empties). To prepare for the test, an individual drinks a chalky barium solution that coats and outlines the walls of the esophagus, stomach, and duodenum. Barium makes the linings of these organs show up more clearly on X rays. An upper GI series can detect problems such as a blockage, abnormal growth, ulcer, hernia, or accumulation of scar tissue. This series is also known as a barium swallow.