The Thyroid Ultrasound Procedure
A thyroid ultrasound is a painless scan that uses sound waves to build a picture of the thyroid gland and surrounding neck tissues. It is the main imaging test for nodules and goitre.
This page describes what happens during the scan and what to expect afterwards.
Last medically reviewed: 15 November 2025
Preparation
There is no special preparation. You can eat, drink and take your usual medications before the scan. Wear clothing that allows easy access to your neck, or you may be given a gown.
During the scan
You lie on your back with your neck slightly extended. A clear gel is applied and a small probe is moved gently over the neck. The sonographer captures images of the gland, any nodules, and nearby lymph nodes.
The scan is completely painless and usually takes 15–30 minutes. You may be asked to swallow or hold your breath briefly.
After the scan
The gel is wiped off and you can go about your day immediately. A radiologist reviews the images and issues a written report.
The report describes the size and appearance of the gland and grades any nodules by their risk features. This guides whether monitoring, biopsy or no action is needed.
What the findings mean
Most nodules seen on ultrasound are benign. Suspicious features prompt a biopsy, while simple cysts and small low-risk nodules are usually just monitored.
Ultrasound findings are interpreted alongside your blood tests and examination — a specialist consultation brings the whole picture together.
Frequently asked questions
Do I need to fast for a thyroid ultrasound?
No — there is no fasting requirement. Eat and take your medications as normal before the scan.
Does the scan hurt?
Not at all. It is painless and non-invasive, using only a gel and a smooth probe on the skin.
Can ultrasound tell whether a nodule is cancer?
It identifies features that make cancer more or less likely and can guide a biopsy, but it cannot confirm cancer on its own — a biopsy provides the cellular diagnosis.
References & further reading
This page is based on established medical knowledge and guidelines from authoritative sources. Always consult a qualified clinician for personal medical advice.
Ready to discuss your thyroid health?
Book a specialist consultation — in person or by teleconsultation.