A barium enema is a radiographic (X-ray) examination of the lower gastrointestinal (GI) tract. The large intestine, including the rectum, is made visible on X-ray film by filling the colon with a liquid suspension called barium sulfate (barium). Barium highlights certain areas in the body to create a clearer picture.
Fluoroscopy is often used during a barium enema. Fluoroscopy is a study of moving body structures — similar to an X-ray "movie." In a barium enema, fluoroscopy allows the radiologist to see the movement of the barium through the large intestine as it is instilled through the rectum.
Barium is a dry, white, chalky, powder that is mixed with water to make barium liquid. Barium is an X-ray absorber and appears white on X-ray film. When instilled via the rectum, barium coats the inside wall of the large intestine. This allows for visualization of the inner wall lining, as well as the size, shape, contour, and patency of the colon. This process shows differences that might not be seen on standard X-rays. Barium is used only for diagnostic studies of the GI tract.
The use of barium with standard X-rays contributes to the visibility of various characteristics of the large intestine. Some abnormalities of the large intestine that may be detected by a barium enema include tumors, inflammation, polyps (growths), diverticula (pouches), obstructions and changes in the intestinal structure.
After the instillation of barium into the rectum, the radiologist may also fill the large intestine with air. Air will appear black on X-ray film, contrasting with barium's white image. The use of the two substances, barium and air, is called a double contrast study.
The purpose of using two contrast substances is to achieve an enhancement of the inside wall lining of the large intestine. As the air expands the large intestine (like blowing up a balloon), a barium coating is formed on the inner surface of the colon wall. This technique enhances visualization by sharpening the outline of the inner surface layer of the large intestine. The benefit of this technique is to show smaller surface abnormalities in the large intestine.
A barium enema may be performed to diagnose structural or functional abnormalities of the large intestine, including the rectum. These abnormalities may include, but are not limited to:
There may be other reasons for your doctor to recommend a barium enema.
You may want to ask your doctor about the amount of radiation used during the procedure and the risks related to your particular situation. It's a good idea to keep a record of your past history of radiation exposure, such as previous scans and other types of X-rays, so that you can inform your health care provider. Risks associated with radiation exposure may be related to the cumulative number of X-ray examinations and/or treatments over a long period of time.
If you're pregnant or suspect that you may be pregnant, you should notify your doctor. Radiation exposure during pregnancy may lead to birth defects.
Patients who are allergic to or sensitive to medications, contrast media, iodine, or latex should notify their health care provider.
Constipation or fecal impaction may occur if the barium isn't completely eliminated from the body. Risks of barium enema may include, but are not limited to:
Contraindications for a barium enema include, but are not limited to:
There may be other risks depending on your specific medical condition. Be sure to discuss any concerns with your doctor prior to the procedure.
Certain factors or conditions may interfere with the accuracy of a barium enema procedure. These factors include, but are not limited to:
PRECAUTIONS: If you are pregnant or suspect that you may be pregnant, you should notify your doctor. Notify the radiologist if you've had a recent barium swallow or upper GI procedure, as this may interfere with obtaining an optimal X-ray exposure of the lower GI area.
Before starting barium enema preparation, please discuss with your physician if:
CLOTHING: You must completely change into a patient gown. Please remove all piercings and leave all jewelry and valuables at home.
EAT/DRINK: Follow the directions below to ensure your colon is properly cleansed and free of waste matter or feces prior to the procedure. Based on your medical condition, your health care provider may request other specific preparation.
Have only clear liquids for the entire day. Drinking lots of clear liquids is a very important part of the preparation. Clear liquids include:
Continue consuming only clear liquids listed above.
At 5 p.m. drink a 10 ounce bottle of magnesium citrate. Have additional clear fluids throughout the evening. Drink a minimum of four eight ounce glasses of clear liquid. Magnesium citrate is available over the counter at any pharmacy.
Continue to follow clear liquid diet until the examination is complete.
A barium enema may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your doctor's practices.
Generally, a barium enema will follow this process:
Following the examination, some barium will be expelled immediately. You'll be assisted to the bathroom or given a bedpan.
You may resume your normal diet and activities after a barium enema, unless your doctor advises you differently.
Barium may cause constipation or possible impaction after the procedure if it isn't completely eliminated from your body. You will be advised to drink plenty of fluids to expel the barium from the body.
Since barium isn't absorbed into the body but passes through your entire gastrointestinal tract, your bowel movements may be lighter in color until all the barium has been excreted.
The long and rigorous bowel preparation prior to the procedure may cause fatigue afterward. You should rest as needed.
You may experience soreness of the anus and rectum due to the bowel preparation. Your doctor may recommend the application of a soothing ointment to the area.
Notify your health care provider to report any of the following:
Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.