Introduction

A micturating cystourethrogram (MCUG) is a type of X-ray that shows how your child’s urinary system is working.

The urinary system includes the:

• kidneys – filter waste from blood to make urine
• ureters – tubes that carry urine to the bladder
• bladder – stores urine
• urethra – takes urine out of the body.

The MCUG uses a radiopaque liquid called contrast. Contrast absorbs X-rays as it moves through your child’s urinary system and shows up white on the images that are taken.

Your child’s treatment team will let you know if there are any special instructions to follow. This may include taking antibiotics before or after the scan to prevent infection.

Let the hospital know if your child has:

• had a urinary tract infection (UTI) in the past four weeks
• any allergies
• ever had a serious reaction to a medical test or scan.

If your child has a heart condition, speak to their specialist before the scan to make sure they have the right antibiotics.

Talk to your child’s care team if you’re unsure about how to prepare.

The scan is done in the Medical Imaging Department of the hospital.

The MCUG has two main parts: 

1. taking images while the bladder fills with contrast
2. taking images while the bladder empties the contrast.

Part 1: Filling the bladder

1. your child lies on an X-ray table
2. the doctor wipes the area around their penis or vagina with antiseptic
3. a numbing gel is used on a small plastic tube called a catheter
4. the catheter is gently inserted through the urethra at the tip of the penis or just above the vagina
5. the catheter is connected to a bag of contrast liquid that is hung up next to the table
6. the liquid flows into the bladder
7. X-ray photos are taken as the bladder fills.

Part 1: Filling the bladder

1. your child lies on an X-ray table
2. the doctor wipes the area around their penis or vagina with antiseptic
3. a numbing gel is used on a small plastic tube called a catheter
4. the catheter is gently inserted through the urethra at the tip of the penis or just above the vagina
5. the catheter is connected to a bag of contrast liquid that is hung up next to the table
6. the liquid flows into the bladder
7. X-ray photos are taken as the bladder fills.

Part 2: Emptying the bladder

1. Your child stays on the table and is given something to collect their urine, like:
   1. a special nappy
   2. an absorbent blue sheet
   3. a bed pan
   4. a urine bottle.
2. they are asked to do a wee while more X-ray images are taken
3. once their bladder is empty, the catheter is removed.

Some children may need to fill and empty their bladder more than once during the scan to get the right images. 

Toilet-trained children may find it hard to do a wee during the scan, especially in front of others. This is normal. 

Parents and carers who are not pregnant can stay to support their child during the scan.

Speak to the treating team about options for pain or anxiety relief if needed.

Your child’s doctor will check the images and arrange a follow-up to discuss the results.

Your child will need to drink plenty of fluids over the next 24 hours to help flush out the contrast liquid from their bladder. It can be normal for them to feel a bit sore and have some blood in their urine during this time.

See your local doctor or go to the emergency department if your child:

• develops a fever
• still has blood in their urine after 24 hours
• passes blood clots in their urine.