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MRI defaecating proctogram

Patient information A-Z

This leaflet aims to answer your questions about having an MRI proctogram.

What is an MRI defaecating proctogram?

An MRI defaecating proctogram is a study which uses magnetic resonance imaging (MRI) to assess the function of your pelvic floor. The examination looks at the way the rectum empties and how the muscles of the pelvis move when you open your bowels.

MRI involves a very strong magnet. You will first be asked a set of safety questions to make sure that you don’t have anything in your body that might be affected by the scans. The MRI scanner is a tube open at both ends. There is no use of radiation or x-rays.

The MRI makes a loud knocking sound, which is normal – you will be given ear protection to help reduce the noise but you will still be able to hear the instructions. You can be seen at all times by the radiographer.

Preparation for your MRI defaecating proctogram

You can eat and drink as normal. If you are taking any medication, please continue to take this.

You will be asked to arrive 20 minutes before your scan. During this time you will:

  • Be asked to complete an MRI safety questionnaire.
  • Have the procedure explained to you and be given an opportunity to ask questions.
  • Be asked to remove all your clothes and metal objects, lock away valuables in a locker and change into a hospital gown.
  • Be given disposable underwear and a pad to wear.

During the MRI defaecating proctogram

A member of the MRI staff will bring you into the scanner room and ask you to lie on your left side on the MRI table. The radiologist will then gently insert gel into your rectum through a small syringe tip. You will be asked to turn onto your back and stay in that position for the rest of the examination. You will be given a call button that will allow you to get the radiographer’s attention at any time. A special camera, called a coil, will be placed on top of your pelvis.

Once you are positioned inside the scanner, the radiographer will start the examination. There will be routine scanning at the start for about four minutes, and then the radiographer will give you two instructions:

  1. “Squeeze and lift” – this is like a pelvic floor exercise; it is meant to hold the gel in. This takes about 30 seconds.
  2. “Bear down and push” – this is to try and push out/ evacuate some or all of the gel. The radiographer will repeat this step up to six times. This will take about 20 seconds each time.

The whole examination takes about 20-30 minutes.

After the defeacating proctogram MRI scan

After the examination is complete you will be directed to the toilet to clean up and dispose of the underwear. You will be free to go home immediately afterwards.

A radiologist will write a report on all the images; this report will be sent back to the consultant who referred you.

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

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Contact us

Cambridge University Hospitals
NHS Foundation Trust
Hills Road, Cambridge

Telephone +44 (0)1223 245151