The information below is about a procedure at the Queensland Children's Hospital and may not apply to other hospitals and health facilities.
A PET-CT scan takes images of organs and tissues inside the body and puts them together to creates 3D images.
Why does my child need a PET-CT scan?
Your child may need a PET-CT scan if a health professional needs to:
- see how different organs in the body are functioning
- detect or manage infections, conditions or diseases
- assess the effectiveness of treatment.
Your health professional will let you know the reason for your child’s scan.
What to expect
The appointment could take up to 3 hours.
Before the PET-CT scan
Before you come to the hospital, we’ll call let you know what type of preparation you need to do for the scan. We’ll also answer any questions you have.
Before the scan, your child will need to have a tracer fluid injected. To do this we’ll need to insert a cannula, this is like having a blood test. Before inserting the cannula, we may apply a numbing cream or cool sense to the area.
If your child already has a central line or port, we’ll use that to inject the tracer instead.
Once they have the tracer, they’ll need to sit still and relax for about one hour.
During the PET-CT scan
PET-CT scans take about 30 minutes.
The PET-CT scanner looks like a big doughnut. For the scan, your child will need to lie on a table that moves through the middle of the doughnut and try to stay still. We may use foam cushions or soft straps to help them stay still.
If they have trouble staying still, they may need to have a general anaesthetic or sedation. Find out more about general anaesthesia.
After the PET-CT scan
After the scan, we’ll monitor your child for a short period and give them something to drink. We’ll also remove their cannula.
A nuclear physician will prepare a report about your child’s PET-CT scan and send it to the health professional who referred them. The health professional should let you know when they get them.
Preparing for the PET-CT scan
The most important things to remember are:
- your child shouldn’t eat or drink anything for 4 to 6 hours before their scan, it can affect the quality of the scan
- make sure your child doesn’t wear clothing with metal clips or snaps and removes all jewellery
- make sure your child wears something warm and comfortable.
How much radiation exposure is in a nuclear medicine study?
Your child will receive a very small amount of radiation, which comes from a radiotracer and, if needed, a CT scan. Nuclear medicine tests have been safely used on children for over 40 years. The low radiation doses and the way these tests work make them a safe and effective option for diagnosing children’s conditions.
Specialists in nuclear medicine make sure your child gets the smallest radiation dose needed for an accurate diagnosis, following a principle called ALARA (As Low As Reasonably Achievable). The amount of radiotracer used depends on your child’s weight, the reason for the test, and the area being scanned. The radiotracers used break down quickly into non-radioactive forms, and part of them leaves the body naturally through urine.
Some parents may be concerned about the small amount of radiation their child might give off after the procedure. However, this exposure is usually much smaller than the natural radiation we all receive each year. In most cases, you can stay with your child during the procedure if you choose.
For more information
Watch our PET-CT scan video to find out more about what it’s like to have a PET-CT scan.