4D CT Thyroid (Parathyroid 4D-CT) Scans Sydney
A 4D CT Thyroid (also known as Parathyroid 4D-CT) is a specialised CT scan used to locate overactive or enlarged parathyroid glands. Using multiple phases of contrast imaging, it helps your doctor diagnose conditions such as primary hyperparathyroidism and plan minimally invasive surgery. This scan is bulk-billed through Medicare at Advicon Imaging.
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Description of 4D CT Thyroid (Parathyroid 4D-CT)
A 4D CT Thyroid (Parathyroid 4D-CT) is an advanced CT imaging technique that helps identify abnormal parathyroid glands. These glands sit behind the thyroid and regulate calcium levels in your body. When one or more become overactive, it can lead to symptoms such as fatigue, kidney stones, bone pain, or elevated calcium levels.
The “4D” aspect refers to the addition of time as the fourth dimension. Images are taken in several phases after an iodine contrast injection—each phase highlights the parathyroid tissue differently. This makes the scan particularly effective in identifying parathyroid adenomas, multigland disease, or, very rarely, parathyroid carcinoma.
This imaging method is extremely useful for patients undergoing work-up for primary hyperparathyroidism. Accurate localisation allows surgeons to plan minimally invasive parathyroid surgery, resulting in smaller incisions, shorter operating times, and a faster recovery.
During the scan, patients receive a small injection of iodine contrast via a vein. The CT scanner then captures images at carefully timed intervals when the contrast is most concentrated in the parathyroid glands. The entire test is quick, safe, and well-tolerated.
At Advicon Imaging, our 4D-CT scans are performed using modern CT technology, and the study is 100% bulk billed if Medicare-eligible, so there are no out-of-pocket costs for most patients.
Frequently Asked Questions
What is a 4D CT Thyroid (Parathyroid 4D-CT)?
It is a specialised CT scan that uses contrast and timed image phases to detect abnormal or overactive parathyroid glands.
Why has my doctor requested this scan?
Your doctor may suspect hyperparathyroidism or wants precise localisation of an abnormal gland before surgery.
Is there any preparation for this scan?
Yes.
- Please hydrate well before your appointment unless instructed otherwise.
- Notify us if you have had a previous reaction to iodine contrast.
- If you have kidney problems, diabetes, or take metformin, let our team know so we can advise you accordingly.
What happens during the scan?
You will receive a small injection of iodine contrast through a vein. The CT scanner will take several images over short intervals while you lie still. The scan usually takes 10–20 minutes.
Is the scan painful?
The scan itself is painless. You may feel a warm sensation when the contrast is injected—this is normal and passes quickly.
Does it use radiation?
Yes, like all CT scans, it uses X-rays. The radiation dose is carefully minimised and justified because the scan provides crucial information for surgical planning.
Is iodine contrast safe?
Most people tolerate it very well. Please tell us if you have kidney issues, thyroid disease, or any previous contrast reactions.
Can I have this scan if I am pregnant?
CT scans are generally avoided during pregnancy. Please inform us immediately if you are pregnant or think you may be pregnant.
How long does the scan take?
The procedure usually takes 10–20 minutes, and you may stay a little longer for observation after the contrast injection.
Do I need someone to drive me home?
No, you can safely drive yourself unless advised otherwise.
When will my doctor receive the results?
Your results are usually available to your referring doctor within 24–48 hours, often on the same day if required urgently.
Is the scan bulk-billed?
Yes. At Advicon Imaging, this examination is fully bulk-billed for Medicare-eligible patients.