What is a Double Contrast Barium Enema?
A double contrast barium enema uses a silver-white compound called barium to outline the colon and rectum on an X-ray. Normally, soft tissues X-ray very poorly, but the barium coating reveals a clear outline of the colon.
There are many procedures that can identify abnormalities in the colon. A double contrast barium enema uses a silver-white compound called barium to outline the colon and rectum on an X-ray. Normally, soft tissues X-ray very poorly, but the barium coating reveals a clear outline of the colon. While the double contrast barium enema is not as comprehensive as the colonoscopy, it is a very useful tool to help diagnose many colorectal issues.
Why “Double Contrast”?
The barium is inserted into the colon and then drained out, with only a thin layer of barium remaining on the colon wall. The colon is then filled with air to expand the colon and provide a more detailed view of the inner lining of the colon. This is called “double contrast” or “air contrast” barium enema.
Why Choose a Double Contrast Barium Enema?
Double contrast barium enemas are low-risk procedures, which are less invasive and often more affordable than a colonoscopies. Double contrast barium enemas can be used to diagnose many conditions such as:
- Inflammatory bowel disease
- Diverticulum (a pouch pushing out from the colon)
- Structural changes in the intestine
A barium enema can also help evaluate abdominal symptoms such as pain, blood in the stool, anemia, persistent constipation or diarrhea, unexplained weight loss or altered bowel habits.
Preparing for a Double Contrast Barium Enema
Your doctor will review your medications and advise you whether you should stop taking any medications before the procedure. The preparation for a barium enema test is similar to the preparation for a colonoscopy. You will have to follow a set diet and complete a bowel preparation before the procedure. Some requirements before the test may include:
- Restricting the intake of dairy products
- Adhering to a liquid diet for 1 to 3 days before the procedure
- Drinking lots of water and clear, noncarbonated liquids
- Taking a combination of laxatives to empty your colon
- Administering a tap water enema to clear any remaining stool from the intestines
What Happens During a Double Contrast Barium Enema?
Your double contrast barium enema will be performed by a radiology technician and a radiologist (a doctor who specializes in imaging). You will lie on your back on a tilting table so your abdomen can be X-rayed to verify that your colon is clear. You will then shift to your side. A rectal tube containing barium will be inserted into your anus, and the barium will slowly fill the intestine. The tube has a small balloon at the tip, and this balloon keeps the barium inside your colon. You may feel some abdominal cramping or feel an urge to have a bowel movement, but taking slow, deep breaths is helpful.
Your radiologist will observe the flow of barium on an X-ray fluoroscope monitor that looks similar to a television screen. Pressure may be applied to your abdomen to move the barium through the intestines.
After the intestines have been filled, the barium will be drained and the colon will be filled with air. Your abdomen will be X-rayed from many different angles to detect any abnormalities in your colon. Throughout the test, you may need to move around on the table or turn to help the barium spread through the colon. The entire procedure lasts anywhere from 30 minutes to an hour, but you will only hold the barium inside your colon for about 10 to 15 minutes.
What Happens After a Double Contrast Barium Enema?
After the enema tube has been removed, you will be given a bedpan to void as much of the barium as possible. You will need a few final X-rays called post-evacuation films. All cramping should subside after the test is complete. Your radiologist will prepare a report from the examination and send it to your doctor who will review the results with you.
A negative result means that the radiologist observed no abnormalities in the colon. A positive result means that the radiologist found abnormalities in the colon that may require further testing. A problem could include:
- A narrowing in the bowel
- Polyps or growths in the bowel
- Sacs in the colon wall (diverticulosis)
- Structural defects and inflammation in the lining of the bowel
- A twisted loop of bowel causing obstruction
- A section of the bowel that did not fill with barium
In the case of a positive or abnormal result, further testing such as a colonoscopy may be recommended. In a colonoscopy, specific abnormalities can be examined, biopsied or removed.
You will be able to go home on the same day of the procedure, but you will want to arrange for someone to drive you home. When you are home, you should try to rest, and you may resume a normal diet. Because you will have lost a high volume of fluids during the bowel prep, it is important that you replenish your body with plenty of liquids.
Your doctor may suggest that you take a laxative to help you pass the remainder of the barium, and your bowel movements may appear white or pink for a few days after the test. You may feel tired after the procedure, or your anus may feel sore because of the frequent bowel movements. Warm baths and an anesthetic gel or cream may help to relieve any discomfort.
There are very few risks in having a barium enema. Some rare complications include:
- Allergic reaction to barium
- Perforation of the colon wall—a very rare condition that can occur when the pressurized air weakens a section of the intestinal wall.
- Obstruction in the GI tract—in rare cases, residual barium may harden and cause impaction. Drinking plenty of fluids and using a laxative or enema after the test should reduce the risk of this complication.
Double contrast barium enema is just one of several methods for colon screening. Factors such as age, family history, personal history, lifestyle habits and insurance coverage may determine which screening method you and your provider choose. Talk to your provider about whether double contrast barium enema is the best colon screening for you. Remember, although colon cancer is the second leading cause of cancer death in the United States, it is preventable with regular colon screenings.