This leaflet gives you information about having a flexible sigmoidoscopy, with a transrectal ultrasound scan, as an outpatient. Your appointment is at the Endoscopy Ward located in the Endoscopy Department at Cheltenham General Hospital. Please report to the Endoscopy Department receptionist on arrival at the hospital.

What is a flexiTRUS?

This is a procedure which allows the doctor to look at the lower part of your large bowel (sigmoid colon). A flexible colonoscope and ultrasound probe is passed through the anus and into the rectum (back passage).

A colonoscope is a flexible tube about the thickness of your index finger with a bright light on the end.

By looking at the screen, the doctor can see the lining of the bowel and check whether any disease is present.

Why am I having this scan?

This scan is performed for different reasons which may include:

  • Assessment of your rectum to help with diagnosis and planning treatment. You may also have been sent for other tests as part of the assessment package.
  • Inspection of your rectum after treatment to check for any changes.

Before the scan

If you are taking regular medication you should continue to take this as normal.

You do not need to fast or make any dietary changes for this procedure.

The physiologist will explain the procedure to you and answer any questions that you may have. When they are sure that you understand the procedure and any risks involved you will be asked to sign a consent form.

You will then be asked to change into a hospital gown.


To help make the scan images clearer we require you to have an enema (small amount of fluid inserted into your back passage) before having the scan. The enema will clear the rectum of any faecal waste which may block the view of the back passage and surrounding tissue.

An enema pack may have been sent by post for you to perform at home. If you are able to give yourself the enema at home you will not need another. If you are unable to do so, please bring the enema with you and a nurse will help.

The toilet will be easily accessible, or a commode can be put next to your bed if you prefer.


There is little risk associated with having a transrectal ultrasound scan. You may feel some discomfort during the procedure or a sensation of wanting to open your bowels.

During the scan

You will be asked to remove or lower some of your clothing, and lay on your left side on an examination couch.

The consultant will insert a clear plastic tube into your rectum. The plastic tube is attached to a light source and air bellows.

To allow the consultant to view the area to be examined, air will be inflated into your bowel before inserting the ultrasound probe. The air will disperse after the procedure and any discomfort will stop.

The ultrasound probe will be inserted through the clear plastic tube. You may feel a sensation of wanting to go to the toilet as a small balloon is slowly filled with water. This allows the probe to rotate and send ultrasound images to a monitor. A copy of these images will be kept in your hospital medical records.

After the scan

You will be discharged after the procedure and you will be able to carry on with your normal routine. It is common to feel slightly bloated with wind for a short time after the test. You will be fit to drive but if you are concerned, please arrange to be accompanied to the appointment or to use public transport.


After the procedure the consultant may discuss your results with you and your partner or relative if you so wish, or an outpatient appointment will be arranged once all of the results are available.

Contact information

Appointment enquiries booking team

Cheltenham General Hospital

Tel: 0300 422 6899

Monday to Friday, 8:30am to 4:00pm

Printable version of this page

FlexiTRUS GHPI1664_02_24 Department: Colorectal Review due: February 2027 PDF, 286.4 KB, 4 pages
Reference number GHPI1664_02_24
Department Colorectal
Review due February 2027