Neck ultrasound: why it is done, what happens and what the results mean

An ultrasound scan is used to see images of the inside of the body, such as muscles and organs. A small device called a probe sends out sound waves and picks up the echoes, and a computer turns those echoes into a live picture on a screen. The NHS describes it as usually done in hospitals or clinics.

A neck ultrasound is simply that scan applied to the neck. The area contains the thyroid gland at the front, rows of lymph glands (also called lymph nodes) down each side and under the chin, and soft tissues in between. Because the structures lie close to the skin, an external ultrasound probe can often show them clearly without any need for an internal examination.

People are sometimes anxious about being sent for a scan of the neck, especially when a lump has been found. A scan is a way of finding out what is there. Many neck lumps turn out to be something common and harmless, and the scan helps the team decide whether anything more is needed.

The NHS says you might be referred for an ultrasound scan to investigate symptoms such as pain or a lump, to monitor a condition such as a problem with your thyroid, or to help a health professional see inside the body during a procedure. For the neck, the most common reasons fall into a few groups.

• A lump at the front of the neck that may be in the thyroid. The NHS lists a lump in the front, lower part of the neck as a main symptom of thyroid cancer, and says it usually feels hard, slowly gets bigger and is not painful. Most lumps are not cancer, but this symptom is one a GP will want to check.

• Swollen glands. The NHS says swollen glands are usually a sign the body is fighting an infection and should go down within 1 to 2 weeks. If they do not, or they feel hard or fixed, a GP may arrange further tests, which can include a scan.

• Following up a known thyroid problem, for example to see whether a swelling has changed in size.

• Guiding a needle. Ultrasound can be used while a sample of tissue is taken, because the operator can watch the needle on the screen.

The NHS advice on swollen glands says to see a GP if the glands are getting bigger or have not gone down within 1 week, if they feel hard or do not move when you press them, if you are having night sweats or a very high temperature, if you have no other signs of illness or infection, or if the swollen glands are just above or below the collarbone.

It also says to ask for an urgent GP appointment or get help from NHS 111 if you have swollen glands and are finding it very difficult to swallow or have difficulty breathing.

For the thyroid, the NHS says to see a GP if you have a lump in your neck, whether new or an existing one that is getting bigger, or if you have had a hoarse voice, sore throat or cough for more than 3 weeks, or pain or a pressing feeling at the front of your neck. It stresses that these symptoms are very common and can be caused by many different conditions, so having them does not definitely mean thyroid cancer.

The NHS says the hospital or clinic should tell you if there is anything you need to do beforehand. Some ultrasound scans of the body need a full bladder, but that applies to pelvic scans rather than the neck, so you will usually not need to drink anything or fast. If you have not been told otherwise, ask the department when you receive your appointment.

You may be asked to remove jewellery or piercings from the area being scanned. Necklaces, scarves and high collars are best left at home or removed, because the probe needs bare skin on the front and sides of the neck.

If you would like someone else in the room with you, you can ask for a chaperone. The NHS says this can be someone you know or a member of staff. You can also ask the person doing the scan to stop at any time.

A healthcare professional will do the scan, and a nurse or healthcare assistant may also be in the room. For a neck scan you will usually be asked to lie on a couch, often with a pillow or support so that your head tilts back slightly. The NHS says the lights may be dimmed to help them see the images on the screen.

A slippery gel is put on the skin over the part being scanned. The operator then moves the probe over the area. They may stop to make notes or take measurements on the screen, and you may be asked to change position, turn your head or swallow so they can view different angles. When the scan is finished you wipe the gel off with paper towel and can get dressed.

The NHS says the probe used for an external ultrasound does not usually cause any pain as it is moved across your skin, although it can be uncomfortable if it presses on an area that is already painful. If you feel pain, tell the person doing the scan and they will help you feel more comfortable.

The NHS says you may get the results at the end of your appointment, or it can take a few weeks, depending on why you had the scan. The result is sent to the doctor who referred you, and you might need a follow-up appointment to discuss it. If you have not heard anything after a few weeks, contact the specialist or your GP surgery.

If you are being investigated for a possible thyroid problem, the NHS says it should take about 2 weeks to get the results of your tests, but sometimes it might take longer. It adds that a long wait does not definitely mean anything is wrong, and that you can call the hospital or GP for an update.

The result may be reassuring, may show a swelling that needs watching, or may lead to a further test. The NHS lists a small needle sample (biopsy) from the thyroid as one of the next steps when thyroid cancer is being checked for, and says you may not have all of the tests it lists. A group of specialists will explain what the results mean and what happens next.

On the NHS, a neck ultrasound is normally requested by a GP or hospital doctor as part of an assessment, and the scan is done in a hospital or community imaging department. The waiting time depends on how urgent the referral is and on local capacity.

Private imaging providers also offer neck ultrasound, often with a shorter wait. Whichever route you use, the result still needs to be interpreted in the context of your symptoms and examination, and the next step is usually a conversation with a doctor rather than the scan report alone. If a private scan finds something, take the report to your GP so that any follow-up can be arranged.