Micturating Cystourethrography (MCU)

A micturating cystourethrography (MCU) is an X-ray examination to look at how the bladder works while a person is passing urine and to detect for vesicoureteric reflux (VUR).

Vesicoureteric reflux (VUR) is a condition where urine flows backwards from the bladder to the kidneys, which can increase the risk of urinary infections.

We hope the following information will help you understand the procedure better and make your visit to Department of Diagnostic and Interventional Imaging (DDII) a pleasant one.

Does it hurt?

The exam is not painful. Your child may feel some discomfort when we insert a thin plastic tube (catheter) into the bladder. They will also feel a strong urge to pass urine during the scan.

Should my child be hospitalised for the procedure?

The eexamination does not usually require hospital admission. It can be performed on an outpatient basis. If your child is hospitalised on the appointment day, inform the ward staff to contact DDII.

How can I prepare my child for the MCU?

As your child may be anxious about the procedure, we strongly encourage you to talk through the procedure with your child to help them understand what will be happening. This will help to encourage them to lie still and cooperate during the procedure.

Ensure your child takes any prescribed antibiotics as instructed by your doctor.

No fasting is required for the procedure. Your child may continue to eat, drink, and take all prescribed medications as usual. You may wish to bring along a toy or book for your child and milk feed (for younger children).

Please arrive at least 30 minutes before your appointment time to register and give your child time to relax and prepare for the test.

What happens during an MCU?

Before the examination, the nurse will gently insert a catheter through the urethra into the bladder. The urethra is the channel where the urine passes out of the body.

Your child will lie comfortably on the bed, and the X-ray machine above them will take pictures during the examination. The radiologist will fill the bladder slowly with contrast medium (X-ray dye) via the catheter; the contrast enables the bladder to be seen under X-ray. The radiographer and radiologist will guide your child into different positions for several pictures.

Infants will pass urine as soon as the bladder is full enough to produce an urge to pee, while an older child will be instructed to pass urine after their bladder is full. Pictures will be taken as the bladder empties when they pass urine. The process may repeat several times to take all the necessary pictures. The catheter will be removed at the end of the examination by the radiologist.

An MCU usually takes about 30-60 minutes, but your visit may take up to a few hours if your child is unable to cooperate during the exam. Your appointment may also be delayed if there are emergencies that require the radiologist’s urgent attention.

What to expect after the examination?
Ensure that your child completes the course of antibiotics prescribed by your doctor for the examination as advised. This is required to prevent any possible (but infrequent) risk of infection during catheterisation.

All or most of the contrast is expected to have been passed out of your child’s bladder during the exam. Do encourage your child to drink plenty of water to flush any possible remaining contrast out of their body.

In the unlikely scenario your child feels any pain or discomfort while trying to pass urine, you may let him/her sit in a bath of warm water to pass urine.

Complications may occur in a small percentage of patients. Please seek medical advice if your child experiences the following:

• Persistent pain or difficulty to pass urine
• Signs of infection eg. Fever, abnormal discharge
• Rashes/itchy areas
• Or otherwise, unwell

Please contact DDII Nurse Station at Tel: 6394 2287 (8am – 5:30pm, Monday – Fridays);
otherwise return to KKH Children Emergency (CE), Basement 1, Children’s Tower.

Inform the doctor/nurse in CE that your child had an MCU done

Radiation dose

The radiation dose your child will receive is small. As such, there are no side effects from the radiation.

How will I know the results of the test?

Your doctor will review and discuss the MCU results during your consultation appointment at the clinic.