This test may be done in an office or a hospital radiology department. You lie on the X-ray table and a preliminary X-ray is taken. You are asked to lie on your side while a well-lubricated enema tube is inserted gently into your rectum.

Barium, a radiopaque (shows up on X-ray) contrast medium, is then allowed to flow into your colon. A small balloon at the tip of the enema tube may be inflated to help keep the barium inside. The flow of the barium is monitored by the health care provider on an X-ray fluoroscope screen (like a TV monitor). Air may be puffed into the colon to distend (expand) it and provide better images.

You are asked to move into different positions and the table is slightly tipped to get different views. At certain times when the X-ray pictures are taken, you hold your breath and be still for a few seconds so the images won't be blurry.

The enema tube is removed after the pictures are taken and you are given a bedpan or helped to the toilet. You then expel as much of the barium as possible. One or two X-rays may be taken after the barium is expelled.

If a double or air-contrast examination is being done, the enema tube will be reinserted gently and a small amount of air will be gently introduced into the colon, and more X-ray pictures taken. This gives a more detailed picture. The enema tube is then removed, and you again empty the colon.

• infant test or procedure preparation (birth to 1 year)
• toddler test or procedure preparation (1 to 3 years)
• preschooler test or procedure preparation (3 to 6 years)
• schoolage test or procedure preparation (6 to 12 years)
• adolescent test or procedure preparation (12 to 18 years)

• annular pancreas
• CMV gastroenteritis/colitis
• colorectal polyps
• Crohn's disease (regional enteritis)
• Hirschsprung's disease
• intestinal obstruction
• intussusception (children)
• pyloric stenosis