The thyroid gland is an important organ that produces several hormones. Various conditions can affect the thyroid, some of which have potentially serious consequences.

For this reason, doctors sometimes use ultrasound scans to produce images of the thyroid gland. These scans might help healthcare professionals diagnose conditions such as cancer, although it is sometimes necessary for them to perform further tests, as well.

This article discusses what ultrasounds are, what the thyroid gland does, and some of the conditions that doctors can detect using thyroid ultrasounds. It also outlines a typical thyroid ultrasound procedure and its limitations. Finally, it answers some common questions about thyroid ultrasounds.

A doctor performing ultrasonography on a person's thyroid.Share on Pinterest
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An ultrasound is a kind of medical imaging technique that doctors may also call ultrasonography. This technology uses very high frequency sound waves to create images of the inside of a person’s body. In some cases, this can allow doctors to make a diagnosis without the need for more invasive techniques, such as biopsies.

Doctors use ultrasound scans to detect problems with the thyroid gland. These scans are a safe, useful, and cost effective way to produce images of the thyroid. They can help doctors diagnose a variety of thyroid problems.

The thyroid is a gland within the neck. As a 2022 article explains, the function of this gland is to produce a range of hormones, including thyroxine (T4) and triiodothyronine (T3). Hormones act as messengers in the bloodstream and tissues, affecting a range of bodily processes.

The thyroid produces hormones that have many different effects, ranging from regulating the body’s metabolism to forming new proteins. Thyroid hormones are also important for healthy fetal development, modulating alertness, and reproductive functions.

Scientists can use thyroid ultrasounds to help detect a wide range of conditions. Thyroid ultrasounds might find evidence for or against the following conditions:

Thyroid ultrasounds can also pick up on benign thyroid abnormalities. Doctors will take care when interpreting ultrasound images, and they may recommend further testing to confirm a diagnosis.

According to the American Cancer Society (ACS), people do not generally need to prepare for ultrasound scans. However, a person’s doctor will inform them about any preparatory steps that they should take.

Typically, an ultrasound scan will last 20–30 minutes. Healthcare professionals can perform ultrasounds in a doctor’s office, at a clinic, or in a hospital.

The healthcare professional will move a transducer over the region after applying a water-based gel around the neck and throat. The transducer emits and receives the ultrasound waves. A computer then analyses the waves, forming an image of the thyroid gland and surrounding tissues.

At the end of the procedure, the healthcare professional will remove the water-based gel from the person’s skin.

Thyroid ultrasounds can help doctors diagnose a variety of thyroid-related conditions. However, it is sometimes necessary to supplement these tests with other diagnostic procedures. This approach can help rule out false-positive and false-negative results.

The ACS explains that although ultrasounds can pick up on thyroid nodules, they cannot always determine whether these nodules are cancerous. For this reason, other diagnostic methods are necessary.

However, doctors may have other uses for thyroid ultrasounds.

For example, when an inconclusive scan has revealed a nodule, doctors may decide to perform a biopsy. This involves using a thin needle to remove part of the nodule, which will then go through laboratory testing. In many cases, doctors will use an ultrasound scan to help guide the needle.

Other tests that can help detect thyroid cancer include:

Below are some of the most common questions and answers about thyroid ultrasounds.

What is a thyroid ultrasound looking for?

Doctors use thyroid ultrasounds to detect any abnormalities within a person’s thyroid. These can range from thyroid cancer, in the form of tumors, to thyroid autoimmune diseases, such as Graves’ disease.

Thyroid ultrasounds can also help doctors monitor the development of thyroid conditions.

Is thyroid cancer visible on ultrasound scans?

Doctors can identify nodules on the thyroid glands using ultrasounds and determine whether they are solid or fluid filled. Solid nodules are more likely to indicate cancer. However, it is not possible to confirm the presence of cancerous cells using an ultrasound.

If a doctor suspects cancer based on the ultrasound, they will order follow-up tests, such as a biopsy.

How does a person prepare for a thyroid ultrasound?

There is no general guidance on what people should do before a thyroid ultrasound. However, doctors may give specific advice on an individual basis.

Thyroid ultrasound scans are safe and effective ways to produce images of the thyroid gland. They can help doctors diagnose a range of conditions.

However, this imaging technique has the potential to produce both false positives and false negatives. For this reason, doctors may sometimes supplement thyroid ultrasounds with other diagnostic tests. Additional tests will always be necessary to confirm a diagnosis of cancer.

Anyone looking for further information about thyroid ultrasound scans should consider speaking with a doctor.