Contrast Enema

A contrast enema is an x-ray study that uses a water-soluble contrast agent containing iodine or barium to show the structure of the rectum, colon, and large intestine. Contrast enemas are commonly referred to as barium enemas.

Water-soluble contrast is a clear liquid containing iodine, and barium is a milky-white contrast liquid. Both show up on x-rays and allow the radiologist to see parts of the body clearly. Most pediatric radiologists use water-soluble contrast during contrast enemas. Both water-soluble contrast and barium are effective and safe contrast agents for enemas in infants and children.

During a contrast enema study, a small tube is inserted into your child's rectum, and the colon and large intestine are filled with contrast material.

Once the contrast fills the colon and large intestine, a special type of x-ray technology, called fluoroscopy, is used to take pictures of these organs.

Why might a contrast enema be needed?

A contrast enema is used to help find the cause of your child's symptoms and diagnose diseases and other problems that affect the large intestine. Some reasons for a contrast enema include:

• abdominal pain
• change in bowel habits
• chronic diarrhea
• detecting problems with the structure of the large intestine
• irritable bowel syndrome
• rectal bleeding
• severe constipation
• unexplained weight loss

How should I prepare my child for a contrast enema?

It is helpful to:

• Give your child a simple explanation as to why she needs a contrast enema.
• Assure your child that you will be there for the entire time. If you are pregnant, you will not be able to be with your child when x-rays are taken. Bring another family member or friend to stay with your child.
• Bring your child's favorite book, toy, or comforting object to occupy her during waiting times.

There are different preparation instructions for a contrast enema according to your child's age, diagnosis, or reason for the study. You will be given specific instructions when you make your child's appointment. It is important that you follow all preparation instructions or the study may need to be rescheduled. In general:

• For most contrast enemas, no preparation is necessary. Your child may eat or drink before the study.
• Some contrast enemas require that your child not eat or drink for a period of time prior to the study.
• Your child can be given his or her usual medication on the day of the study.

What should I expect when I bring my child to the hospital for a contrast enema?

When you arrive, please go to the Department of Radiology check-in desk.

• A patient experience representative will check in your child and verify her registration information.
• A radiologist or technologist will explain the study to you and your child and answer your questions.
• Your child will change into hospital pajamas.
• For women and girls who have begun to have periods (menstruate), a pregnancy test will be required before the study begins.

What happens during the contrast enema study?

You and your child will be taken to the procedure room, where the fluoroscope is used to take x-rays. Your child will be awake at all times during the contrast enema study.

• Your child will need to lie on the x-ray fluoroscopy table.
• A technologist will take a preliminary x-ray of your child's abdomen.
• The radiologist will place a small tube into your child's rectum. The length and width of the tube is determined by your child's age and/or size. The tube will be connected to a bag containing the rectal contrast.
• Your child's large intestine will slowly be filled with contrast. The radiologist may push on your child's stomach during the study to move the contrast around.
• Your child will be asked to roll from side to side as the x-rays are taken using the fluoroscopy machine.
• The technologist may take another routine x-ray after the study.
• Contrast will be drained from the colon as best as possible at the conclusion of the study.

A contrast enema study takes about 15 to 30 minutes.

Will my child feel anything during the contrast enema?

• There is some discomfort during the insertion of the tube into the rectum. Taking long, deep breaths will help your child feel better.
• As the colon and large intestine fill with contrast, your child will feel as if he or she has to have a bowel movement. This feeling is normal.
• Some discomfort or cramping pain may occur during the test, but it generally lasts only for a short time.

What happens after the contrast enema study?

When the enema is done, your child will be ready to go home or see his or her doctor if an appointment is scheduled.

• Your child can resume his or her usual activities and normal diet after the study.
• Your child should drink plenty of fluids.
• Your child's stools may appear white for a couple of days after the enema if barium is used.

One of our radiologists will review your child's images and create a written report of the findings and diagnosis.

How do I learn the results of the contrast enema study?

The radiologist will provide a report to the doctor who ordered your child's contrast enema. The doctor will then discuss the results with you.

How Boston Children's Hospital approaches a contrast enema

Performing contrast enemas in children poses unique challenges. We provide a soothing, kid-friendly environment.

• Pediatric radiologists, with extensive experience and training, perform the procedure.
• Technologists have years of experience in imaging children from infancy to teenagers
• Skilled staff employ age-appropriate distraction techniques to help comfort patients prior to and during the procedure.
• Equipment is designed specifically for pediatric use, which means age-appropriate care for children.
• Protocols have been adapted to keep radiation exposure as low as reasonably achievable without compromising the image quality.

Contact us

Department of Radiology
Boston Children’s Hospital
300 Longwood Ave
Boston, MA 02115
Scheduling: 617-919-SCAN (7226)
More information: 617-355-6286