Thyroid scan Factsheet
Introduction
The thyroid gland is located at the front of the throat and has two lobes on each side of the windpipe. It makes chemicals called hormones that manage your child's growth and energy levels.
The thyroid scan is used to check:
- how big it is
- the shape
- where it is
- how well it is working.
The thyroid scan uses:
- a Gamma camera - a large camera that measures radiation
- radiotracer – an injection of radioactive fluid that moves through the body.
The gamma camera shows the radiotracer being absorbed into the thyroid gland.
Before the scan
Your child can eat and drink normally before the scan.
Your child will be weighed to help calculate the correct amount of radiotracer.
The risks of radiation and allergic reactions are very low. Let your child’s treatment team know if they have any allergies.
Speak to your child’s treatment team before the scan if your child:
- has any allergies
- is taking any thyroid medications, as they may need to stop them
- has had a CT scan with contrast dye in the past three weeks.
Talk to your child's doctor or treatment team if you have any concerns or questions.
Numbing cream
Injections can be uncomfortable for children. To make this easier, numbing cream can be used on children over 2 years old.
If your child needs numbing cream, you will need to:
- ask for it before the day of the scan
- arrive 30 minutes early to the appointment so it has time to work.
During the scan
The scan takes about one hour; you can stay with your child.
Your child will not feel anything during the scan, and the camera will not touch them.
Your child must stay very still during the scan because movement can affect the images. If your child moves, the scan might need to be done again.
Radiotracer:
The radiotracer is injected into your child’s vein using a small butterfly needle. It will travel to the thyroid over 20 minutes.
The scan:
- your child will lie on the scanning bed
- a blanket with velcro straps may be used to help keep your child still
- a pillow or blanket may be placed under your child’s shoulders to help extend their neck and get a better image of the thyroid gland
- over 30 minutes, the camera will take images of your child’s neck and chest from different angles.
After the scan
You can leave once the results are checked by a doctor or nuclear medicine scientist.
The results will be sent to your child’s doctor within a couple of days. You will need to schedule a follow-up appointment with your child’s doctor to discuss the results.
Management
Radiation
Your child will be exposed to a small amount of radiation during the scan. The benefits of finding and treating kidney problems are greater than the small risk of this low dose.
Allergic reactions
Allergic reactions to radiotracer are very rare and usually mild. Your child’s doctor will talk to you about any potential risks before the scan. Let your child’s treatment team know if they have any allergies.
Supporting your child during the scan
Scans can be stressful for children. You can help by:
- explaining why the test is needed and how it works in simple words
- bringing comfort items like a blanket, toy, or dummy
- asking the treatment team about support from Child Life Therapy services
- arriving 30 minutes early if using numbing cream.
