Goitre - Diagnosis 

If you have a goitre, your GP will carry out a physical examination of your neck, and may test your thyroid gland (a gland in your neck that produces hormones) to see how well it is working.

Physical examination

Your GP will examine your neck to assess the size and extent of any swelling, and determine whether it is:

• a diffuse small goitre - where your entire thyroid gland swells up
• a nodular goitre - where certain sections, or 'nodules', of your thyroid gland swell up

They may also ask you to swallow to see whether the lump moves up and down as you do.

Your GP may arrange for a thyroid function test in order to discover the underlying cause of your goitre.

Thyroid function test

A thyroid function test measures the level of certain hormones (chemicals produced by the body) in your blood.

The thyroid gland produces two hormones:

• thyroxine
• triiodothyronine

An excessive amount of these two hormones would indicate an underlying condition that is making your thyroid gland over-active, such as Graves' disease (an autoimmune condition that causes your body to attack itself).

If your thyroid gland is under-active, your pituitary gland (a pea-sized gland that sits below the brain) will produce a hormone called thyroid stimulating hormone (TSH).

TSH is released by your body in order to stimulate your thyroid gland. A high level of TSH in your blood would indicate that your thyroid gland is under-active.

Further tests

If you are referred to a specialist (see box to the right), you may have some further tests that are carried out in hospital. These are described in more detail below.

Radioactive iodine scan

During a radioactive iodine scan, a small amount of radioactive iodine is injected into your vein. The iodine then builds up in your thyroid gland and can be studied using a special camera.

The scan can provide more information about the structure and function of your thyroid gland. The amount of radiation that is used is perfectly safe for most people, although it may not be suitable if you are pregnant.

Ultrasound scan

An ultrasound scan is a procedure that uses high frequency sound waves to create an image of part of the inside of your body. It can be used to:

• build up a picture of the inside of your thyroid gland
• assess the size of your thyroid gland
• check if there are any enlarged nodules in your thyroid gland that have not been found during the physical examination

See the Health A-Z topic about Ultrasound scans for more information about this procedure.

Fine needle aspiration

Fine needle aspiration is a procedure that is used to extract a sample of the goitre (biopsy) to test the cells inside it.

During the procedure, a fine needle on the end of a syringe will be inserted into the goitre in your throat. A sample of the fluid or tissue inside the goitre will be sucked through the needle and into the syringe. The sample will be examined under a microscope in order to determine what kind of cells are inside the goitre.