Colonic Manometry

At Boston Children’s GI Motility Center, we provide the most advanced, high-resolution manometry testing possible. This provides our doctors with detailed information about your child’s condition.

A colonic manometry is a test where a doctor places a small and flexible tube through the rectum, into the colon, to measure how your child’s colon moves. It is done to help find the cause of your child’s motility concerns, such as constipation, stool accidents or other bowel problems.

What Happens Before a Colonic Manometry Test?

Depending on the underlying problem, your child may be admitted to the hospital two days before the manometry so their colon can be cleaned out for the test. Sometimes the cleanout is performed at home. Your child will have a colonoscopy with a colonic catheter placed by the doctor the day before the motility test, or the same day as the test.

What Happens During a Colonic Manometry Test?

A typical, high-resolution colonic manometry test at Boston Children’s involves the following steps.

  • You will bring your child to the Radiology Department at Boston Children's early in the morning (usually around 6 a.m.) the day of the test to check the placement of the catheter. Your child will be transferred to the specialized motility procedure area. A computer cart will be brought into your child’s room and set up on the right side of your child’s bed.
  • Your child will be asked to go to the bathroom before the catheter is connected to the computer. Once the catheter is connected, your child will be unable to get out of bed and will have to use a bedpan or urinal.
  • A gastroenterology technologist or doctor connects the tube to the computer cart. The ports of the catheter will be flushed with sterile water.
  • Your child may feel a sensation on his or her leg due to the temperature change of the water but this will not cause pain.
  • This tube is then attached to a computer that measures how well the colon works during the test.
  • Your child will be given a special meal two hours after the catheter is connected and the test has started. The nurse or technologist will call the kitchen to have the meal delivered at the specified time. Your child will be asked to eat as much as possible over 30 minutes.
  • An hour and a half after the meal is complete; your child will be given a medication directly into his colon, through the catheter. The medication stimulates the colon. Some children experience cramping or bowel movements during this time of the test. They are able to use a bedpan while the tube is in place.
  • On most occasions a second dose of medication will be administered 20 minutes after the first.
  • The study will end once the colon becomes quiet again after the medication is given. This can take anywhere from 45 to 120 minutes.
  • The entire test will take approximately four to six hours to be completed. The gastroenterology technologist or doctor will remove the tube when the test is finished.

When the tube is removed, a Boston Children's gastroenterology doctor will interpret the information recorded by the computer. Call your child's gastroenterologist two weeks after the study for the results. The primary doctor will give follow-up care instructions to you.

If you have any questions about an upcoming test, procedure or any other aspect of your child's treatment, please reach out to any member of your care team—he or she will be able to explain what to expect during your visit and share tips on how to make it as easy as possible.