Radionuclide thyroid scan
A radionuclide thyroid scan shows the structure of your thyroid gland and looks at how well it is working. It can be used to help diagnose and monitor thyroid conditions.
When you would have a thyroid scan
Your healthcare provider may refer you for a thyroid scan if they suspect something may be wrong with your thyroid, or they want to monitor an existing thyroid condition.
You may have a scan to help identify or diagnose:
- lumps, nodules (cysts), or other growths
- inflammation or swelling
- an overactive thyroid (hyperthyroidism)
- an underactive thyroid (hypothyroidism)
- goitre (enlarged thyroid)
- thyroid cancer.
The scan may also be used to look at changes in your thyroid following medication or surgery for a thyroid condition.
How a thyroid scan works
You will usually have your thyroid scan in a hospital as an outpatient.
A very small amount of radioactive material is injected into one of your veins, which is then taken up by your thyroid. A special camera called a gamma camera is then used to give a picture of the radioactive material in your thyroid gland.
Before your thyroid scan
Tell your healthcare provider before your scan if you are pregnant or think you may be pregnant. In this case your healthcare provider may advise that you do not have the scan due to the possible risk to your baby.
Also tell them if you are breastfeeding as you may need special instructions. Some radioactive material can be excreted in breast milk.
Let your healthcare provider know if you are taking any medications or supplements. You may be asked to stop some for a few days before the test.
Healthcare services may be provided to you only if you make an informed choice and give informed consent to it. This forms part of your rights (Rights 5, 6 and 7) under the Code of Health and Disability Services Consumer Rights (the Code).
The Code and Your Rights/Ōu Mōtika — Health & Disability Commissioner
The 3 rights that together allow for informed consent are:
- Right 5 — the right to effective communication
- Right 6 — the right to be informed
- Right 7 — the right to choice and consent.
This means you must be told about the service being suggested, including any risks or possible complications. You must have the chance to ask as many questions as you need to understand the information you are given.
You also have the right to have someone with you to help you. But the decision to say 'yes' or 'no' must be yours (unless you are unable to make that decision due to illness or other impairment, or sometimes in an emergency).
You also have the right to be given the information in a language you fully understand. You can ask for an interpreter if you need one.
After your thyroid scan
Side effects from a thyroid scan are rare.
The radioactive chemicals used in radionuclide scans are considered safe and they leave the body quickly. The dose of radiation is about the same or less than the amount you would get from having an x-ray.