Micturating Cysto Uretherogram (MCU) - CHW

Disclaimer: This fact sheet is for education purposes only. Please consult with your doctor or other health professional to make sure this information is right for your child.

PDF Versions Available

This fact sheet is available to print in the following languages:

What is a cystogram (MCU)?

MCU is a test that makes it possible to look at your child's bladder using a special contrast liquid under x-ray.

What is contrast?

Contrast is a clear liquid containing a radiopaque substance which makes the bladder easier to see.  All the contrast passes out of the body very quickly in the urine.

What happens in MCU examination?

The MCU is a test carried out in the Medical Imaging Department at The Children’s Hospital at Westmead.  In this examination, we look to see if the urine in the bladder is refluxing to the kidneys.

The test is performed in a room with an X-Ray table and a large camera above it. An image is seen of the bladder and urethra.

Your child will lay on the table and you may stand near your child’s head so you can talk to him/her and hold his/her hands.  The child’s groin is cleaned with antiseptic solution.  Local anaesthetic gel is placed on the end of a tiny plastic tube, called a catheter.  The tip of the catheter is passed into the bladder. The catheter used is smaller than the child’s urethra. This can cause discomfort and may upset your child.

The catheter is then connected to the bag of contrast liquid, which is hung by the side of the table. As the bladder fills, the contrast liquid makes the bladder look like a black balloon.  Once the bladder is full, X-Ray images are seen intermittently as the child voids.  The filling up and emptying of the bladder may be repeated during the examination.

Special towels are placed under the child while he/she is emptying his/her bladder. A urinary bottle or bedpan can be given to an older child.

Once the bladder is empty and the final images have been taken, the test is finished and your child can get dressed.  The doctor makes sure that all necessary images have been taken, and then the test is complete.

Advice for parents

  • If your child has a cardiac condition, please ask your cardiologist for the correct antibiotic cover.

  • It is very important that your child is not suffering from a urinary tract infection for the 4 weeks prior to the test.

  • Your child may be requested to take antibiotics before and after the examination according to the doctor’s instructions.

  • Encourage your child to drink plenty of fluids for 24 hours after the test so as to flush the bladder.

  • Your child may be a little sore when they go to the toilet for the rest of the day, but this sensation will go away quickly.

  • Urine might be bloodstained in the 24 hours following the test, but it will return to normal.

  • If your child is unwell, such as a fever, continuous bloodstained urine or blood clot, you should take your child to see your GP or attend The Children’s Hospital at Westmead Emergency Department.

  • MCU can be an uncomfortable procedure for older children. Nitrous oxide is available for children 2 ½ years and older.

  • You may ask your doctor if your child is medically suitable for nitrous oxide so the referring doctor may request MCU with nitrous oxide.

  • For further information on nitrous oxide it is recommended that you contact the Medical Imaging Department to speak to the nurse.


  • Your child will feel more comfortable if a parent or carer stays with them during the examination.
  • Women who are pregnant are not allowed to enter the procedure room, therefore an alternative family support person is recommended.
  • If you have other children, under 18 years, it is suggested where possible, that these children do not accompany you to the appointment, as there is limited waiting space in the Medical Imaging area and they are not allowed into the procedure room with you.
The Children's Hospital at Westmead

For publications recommended by our hospitals' experts, please visit the Kids Health book shop.