A barium computed tomography (CT) scan is a medical procedure in which parts of a person's stomach and intestines are chemically highlighted with a barium sulfate solution to make it easier to see on x-rays. Patients should drink a liquid barium compound at set intervals before the procedure, although the compound can also be introduced by enema if necessary. The barium acts as a contrast agent and makes the stomach and intestines show up better on the scans. This generally contributes to more accurate diagnoses of what are often complex intestinal conditions.
Doctors often order CT scans to get a kind of "insider view" of what's going on under the skin. CT scans are essentially enhanced X-rays. A traditional x-ray is a single image captured from a single angle. CT scans use the same basic technology, but capture images from multiple angles that can then be compiled into a three-dimensional image. A barium CT scan is almost always a CT scan of the stomach or digestive tract.
There are many different reasons for a barium CT scan, although cancers and abnormal growths in the stomach and intestines are among the most common. The presence of barium can help shed light on even the slightest abnormalities. A standard CT scan is often very helpful for initial diagnosis, but barium-enhanced scans go further by helping doctors identify unusual growths and monitor the progress of the disease. In almost all cases, a patient will have a standard CT scan without contrast before undergoing a barium CT scan.
Liquid barium helps improve abdominal and pelvic scans by coating the lining of the stomach and intestines. The compound is not a permanent dye, and it generally leaves the body relatively quickly after entering. Its main benefit lies in how it interacts with the emissions from the CT scanner. When present in significant enough doses, it will often block the rays directly, resulting in a bright, clear image that outlines problem organs and areas.
However, barium is not without its side effects. Patients ordered to undergo a barium CT scan often report that drinking the barium is the most difficult and uncomfortable part of the procedure. This is due in part to the amount that must be consumed, as well as its thick, chalky texture and generally unpleasant taste. Its side effects, which include nausea and loose bowels, can be long-lasting. The scan itself, on the other hand, is usually quite quick and painless.
A patient undergoing a barium CT scan is typically instructed to drink large amounts of the liquid compound at set intervals before the procedure, often several cartons' worth. All other foods and drinks should generally be avoided, including water. Anything but barium in the stomach can skew the results.
In rarer cases, the barium can also be inserted directly into the intestines through an enema. This procedure is most often ordered for CT scans focused on the lower intestinal tract. Because of the discomfort they cause most patients, these types of CT scans are usually only prescribed when the results of other tests, such as colonoscopies, have been inconclusive.