What does a neck ultrasound show?
A neck ultrasound can be used to assess the thyroid gland (the gland that enlarges in goitre), the salivary glands and the lymph nodes.1,2
The thyroid gland regulates the rate at which the body works, and nodules (masses) are common within it: up to 60% of adults have at least one, and most are benign and need no treatment.3,4
Inflammation, stones and masses are also frequently encountered in the salivary glands. A neck ultrasound helps to tell these causes apart.2,5
The lymph nodes in the neck can enlarge while fighting off germs, and also as a result of cancer cells spreading to the lymph node. Lymph nodes also have their own cancers, called lymphoma. Neck ultrasound is widely used to distinguish between these conditions.2
A neck ultrasound also gives useful information for diagnosing swellings that arise from blood vessels and nerves and of certain congenital cysts seen in the neck; with a congenital cyst it shows the size of the mass, its relationship to the surrounding structures and that it is filled with fluid.2,6
Neck ultrasound is an imaging technique that requires no preparation and involves no radiation. If required, a fine-needle sample can also be taken during the same ultrasound examination.1,3
Who needs a neck ultrasound?
A neck ultrasound is the test to have when a lump is felt in the neck, when a thyroid nodule is suspected, or when a nodule has been seen by chance on another scan. In these situations it shows whether the lump arises from the thyroid gland or from a neighbouring structure, and whether a nodule has features that call for a needle sample.3,4
Why is it not advised for everyone?
Not everyone needs a neck ultrasound at a check-up. For adults who have no complaint and no lump in the neck, guidelines advise against screening the thyroid with ultrasound: most of the nodules that screening finds are benign and need no treatment, and its likely consequences are diagnoses and treatment that were not needed.4,7
Ultrasound is sensitive enough to show many nodules that cannot be felt. Even when a cancer is found, most are small, slow-growing tumours confined to the thyroid gland. Population data suggest that screening increases the number of people diagnosed with thyroid cancer without changing the death rate from the disease; there is also considerable evidence documenting the harms of treatment with surgery and radioactive iodine.3,4,7
That advice does not cover people with hoarseness, pain, difficulty swallowing or a lump or swelling in the neck, nor people at higher risk of thyroid cancer, for example after exposure to radiation or with a first-degree relative (a parent, brother, sister or child) who has had thyroid cancer. Whether a neck ultrasound belongs in your check-up is therefore decided with your doctor, from your complaints, your history and the examination of your neck.7
What happens if a nodule is found?
Finding a nodule is not a diagnosis of cancer: in unselected groups of patients, the proportion of thyroid nodules that turn out to be cancer generally ranges from 1% to 5%. The first assessment brings together your personal and family history, the examination of your neck, a blood test of how the thyroid is working and the neck ultrasound.4
On ultrasound the nodule is placed in a risk category according to its appearance. Whether a fine-needle sample is taken is decided together with you, from this category, the size of the nodule and your examination and test results; the sample is taken under ultrasound guidance and examined under a microscope.3,4
Nodules that do not need sampling are followed by risk category and size: some small, low-risk nodules need no further evaluation, and for the others the ultrasound is repeated after six months to five years. When the sample shows cancer or is suspicious for it, the guideline recommends surgery; for nodules of 5 to 10 mm, close follow-up or a minimally invasive treatment may be considered instead.4
When should you see a doctor?
It is advisable to see a doctor if you notice any of the following:7,8
- A lump or swelling in your neck
- Hoarseness
- Difficulty swallowing, or pain when swallowing
- Difficulty breathing
Other conditions can cause the same symptoms, but they are still a reason for an examination of the neck. If you received radiation to the head and neck as a child, or a first-degree relative has had thyroid cancer, tell your doctor: these substantially increase the risk of thyroid cancer.7,8
References
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Lewis-Jones H, Colley S, Gibson D. Imaging in head and neck cancer: United Kingdom National Multidisciplinary Guidelines. J Laryngol Otol. 2016;130(S2):S28-S31. doi:10.1017/S0022215116000396 ↩
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Furukawa M, Hashimoto K, Kitani Y, Yoshida M. Point-of-care ultrasound in the head and neck region. J Med Ultrason (2001). 2022;49(4):593-600. doi:10.1007/s10396-022-01266-8 ↩
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RadiologyInfo.org. Thyroid ultrasound [Internet]. Oak Brook (IL): Radiological Society of North America; [reviewed 2023 May 1; cited 2026 Oct 12]. Available from: radiologyinfo.org ↩
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Durante C, Hegedüs L, Czarniecka A, Paschke R, Russ G, Schmitt F, et al. 2023 European Thyroid Association clinical practice guidelines for thyroid nodule management. Eur Thyroid J. 2023;12(5):e230067. doi:10.1530/ETJ-23-0067 ↩
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Katz P, Hartl DM, Guerre A. Clinical ultrasound of the salivary glands. Otolaryngol Clin North Am. 2009;42(6):973-1000. doi:10.1016/j.otc.2009.08.009 ↩
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Fanous A, Morcrette G, Fabre M, Couloigner V, Galmiche-Rolland L. Diagnostic approach to congenital cystic masses of the neck from a clinical and pathological perspective. Dermatopathology (Basel). 2021;8(3):342-358. doi:10.3390/dermatopathology8030039 ↩
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US Preventive Services Task Force. Thyroid cancer: screening [Internet]. Rockville (MD): US Preventive Services Task Force; 2017 May 9 [cited 2026 Oct 13]. Available from: uspreventiveservicestaskforce.org ↩
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National Cancer Institute. Thyroid cancer treatment (PDQ®)–patient version [Internet]. Bethesda (MD): National Cancer Institute; [updated 2025 Feb 12; cited 2026 Oct 5]. Available from: cancer.gov ↩