Upper gastrointestinal series tract in addition to barium, and this procedure is called double-contrast imaging. In this case the gas is referred to as the negative contrast medium. Traditionally the images produced with barium contrast are made with plain-film radiography, but computed tomography is also used in combination with barium contrast, in which case the procedure is called CT enterography. Various types of barium X-ray examinations are used to examine different parts of the gastrointestinal tract. These include barium swallow, barium meal, barium follow-through, and barium enema. The barium swallow, barium meal, and barium follow-through are together also called an upper gastrointestinal series
Lower gastrointestinal series ulcerative colitis and Crohn's disease. Polyps can be seen, though not removed during the exam like with a colonoscopy— they may be cancerous. Other problems such as diverticulosis (small pouches formed on the colon wall that can become inflamed) and intussusception can be found (and in certain cases the test itself can treat intussusception). An acute appendicitis or twisted loop of the bowel may also be seen. If the picture is normal a functional cause such as irritable bowel syndrome (IBS) may be considered. In a healthy colon, barium should fill the colon uniformly and show normal bowel contour, patency