X-rays use waves of electromagnetic radiation to form images of organs and other structures inside the body. They are absorbed in differing amounts by different body tissues. Skin, fat, and muscle allow more x-rays to pass through, but bones are denser and absorb x-rays. The ultimate result is a shadow on a film that shows images of bones as white, and softer tissues as shades of gray.
Plain x-rays take less than a minute.
How X-Rays Work:
In diagnosing inflammatory bowel disease, x-rays are usually not done alone. However, x-rays are done as a part of longer procedures such as a barium enema or an upper GI series. X-rays also may be used if a bowel obstruction or toxic megacolon is suspected. With these conditions, passing barium through the GI tract to do a contrast x-ray may not be possible.
X-rays can be used to detect cancer, as in a mammography (for breast cancer) or a barium enema (for colorectal cancer). They are routine procedures used to check for cancer in adults. Very high doses of x-rays may be used in cancer treatment.
Preparing for an X-Ray:
Each different type of x-ray procedure has its own specific preparation. X-rays of the digestive tract may require fasting or diet changes, while mammographies require that the patient must not use deodorants, powders, perfumes and creams which may produce abnormal shadows. All jewelry should be removed from the body part to be x-rayed.
For x-rays of the gastrointestinal tract, the stomach, small intestine, and/or colon may need to be clear of food and stool. Therefore, either a period of fasting, or a preparation to clean the colon might be needed.
How They're Done:
You will be asked to remove any clothing over the part of the body to be x-rayed. If necessary, you will be given a hospital gown, and a protective lead drape to shield the rest of your body from the x-rays. While either lying or sitting on a table in an x-ray room, a technician will position you to give the best x-ray view.
The x-ray machine will be positioned near your body so that the x-ray tube is aimed at the proper body area. The technical will stand behind a protective panel and activate the x-ray machine.
Modern techniques and equipment can minimize x-ray exposure and protect reproductive organs during the procedure, but parents should make sure x-rays are absolutely necessary for growing children, and insure that their children's bodies are exposed as little as possible.
By keeping track of when and where you have had x-rays in the past, you can avoid having the tests repeated, and thereby lessen your exposure to x-rays. After 7 to 10 years, x-ray facilities may destroy films, so you may want to obtain them to keep in your records.
X-Rays and Women:
If you are a woman and there is a chance you could be pregnant, tell your doctor before you have an x-ray, as it may affect a developing fetus.
Call your doctor in a few days to find out the results of your x-rays.
X-rays usually have no side effects. If contrast medium was injected before the x-ray, contact your doctor if you experience bleeding, pain, swelling, or redness at the injection site. Ask your doctor for any other instructions.
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National Institute of Diabetes and Digestive and Kidney Diseases. Crohn's Disease. National Institutes of Health. Feb 2006. Oct 12 2007.
Bentley-Hibbert S. X-ray. A.D.A.M. 23 Oct 2006. Oct 12 2007.