A barium enema is an X-ray exam of the large intestine (colon and rectum). It may also be called a lower gastrointestinal (GI) exam. The test is used to help find diseases and other problems that affect the large intestine. 

There are two types of barium enemas.

• In a single-contrast study, the colon is filled with barium. This outlines the intestine and shows large abnormalities.
• In a double-contrast or air-contrast study, the colon is first filled with barium, and then the barium is drained out. This leaves only a thin layer of barium on the wall of the colon. The colon is then filled with air. This provides a detailed view of the inner surface of the colon. It makes it easier to see narrowed areas (strictures), diverticula, and swelling.

A feeding tube is a device that’s inserted into your stomach through your abdomen. It’s used to supply nutrition when you have trouble eating.

An upper gastrointestinal (UGI) series looks at the upper and middle sections of the gastrointestinal tract. The test uses barium contrast material, fluoroscopy, and X-ray. Before the test, you drink a mix of barium (barium contrast material) and water. The barium is often combined with gas-making crystals. Your doctor watches the movement of the barium through your esophagus, stomach, and the first part of the small intestine on a video screen. Several X-ray pictures are taken at different times and from different views.