CT scan

A CT scan, also known as a CAT scan or computer tomography, takes X-rays images from a lot of different angles and in very thin slices. All of these X-ray images come together to produce the CT scan – it’s a bit like slicing a loaf of bread. CT scans can be done on any part of the body.

Watch the video below to find out more about what it’s like to have a CT scan at the Queensland Children’s Hospital.

Why does my child need a CT scan?

CT scans are used to help diagnose lots of different conditions, which may be caused by an injury or illness. For example, a CT scan may be needed to:

  • investigate a head injury
  • look at the shape or structure of different body parts
  • check for signs of disease
  • help with planning before an operation
  • plan follow-up treatment after a procedure.

There are many reasons why your child may need a CT scan, the above are just a few examples. Your referring doctor will discuss this in more details with you before you visit the hospital.

What to expect

How you prepare for your child’s CT scan will depend on which part of their body needs to be scanned.

Your child may need to have a special X-ray dye, called intravenous (IV) contrast, injected before their CT scan. This helps to highlight the blood vessels in the body. The IV contrast is a clear fluid given through a cannula, which is inserted into a vein, usually in the arm. This is a little bit like having a blood test. Before having the cannula, a numbing cream or cool sense may be applied to help numb the area.

Your child will get a warm flush or metallic taste in their mouth shortly after the IV contrast is injected. These are normal symptoms of contrast injection, but can be startling when it is not expected. Explaining to your child that this is going to happen before their scan can help them remain calm.

If your child is having an abdominal scan, they may be a need to drink oral contrast dye 90 minutes before they have their scan. The oral contrast dye highlights the bowel and allows your child’s radiologist to differentiate between the different organs in the abdomen. This oral contrast dye may be mixed with your child’s favourite drink, so it’s a good idea to bring some with you on the day of their scan.

Before you come to the hospital, a nurse will call to confirm your child’s appointment and will let you know what type of preparation you need to do for your child’s CT scan.

The CT scanner looks like a big doughnut, and your child will be able to choose their favourite colour to light up the middle! For the scan, your child will need to lie down on the table which moves through the middle of the doughnut and try their best to stay very still.

All jewellery and items of clothing that contain metal (e.g. zippers) will need to be removed before your child has their scan. It’s a good idea to think about this when your child is getting dressed the morning of their appointment.

For chest and abdomen scans, your child may need to hold their breath for up to 5 seconds at a time. We encourage you to practice breath holds and lying still at home with your child before their appointment.

Your child will be able to leave straight after their CT scan, as long as they have not had contrast dye. If a contrast dye was needed, your child will need to be observed for around 15 minutes after their scan. Reactions to this type of contrast dye are very rare, but if your child does have reaction our staff will be on hand to manage it safely. Their cannula will be removed after the observation period.

If your child has any delayed reactions to the IV contrast at home, please call 000 or present to your closest emergency department.

A specially trained radiologist will review your child’s CT scans and create a report about what was found. This report will then be sent to your referring doctor, who will contact you to discuss the results. Please note that your child’s results cannot be given out over the phone. If you have any questions about the results of your child’s CT scan, please contact their referring doctor.

This service is available at

Medical Imaging and Nuclear Medicine (1a)
Queensland Children’s Hospital

Level 1
501 Stanley Street
South Brisbane
QLD 4101
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Contact details

t: 07 3068 3100  |  07 3068 1111 (after hours via hospital switchboard)

Operating hours

Monday to Friday, 8am–5pm.