In this article:
- Why you may need a thyroid ultrasound
- How ultrasound works
- How to prepare for an ultrasound
- What your ultrasound results mean
If your thyroid health is in question, your doctor may order several tests to examine your thyroid function. Along with thyroid blood tests, such as TSH, T4, and T3, your doctor may order an ultrasound to look at the thyroid. The thyroid gland often undergoes anatomical changes when it is not functioning correctly. Ultrasounds are quick, painless, and often inexpensive studies that can reveal a lot of information about your thyroid gland.
Why you may need a thyroid ultrasound
Chances are, your doctor will order an ultrasound of your thyroid shows signs of disease. For example, your thyroid gland may change in size if you have hyperthyroidism (too much thyroid hormone) or hypothyroidism (too little thyroid hormone).
Suppose you struggle with symptoms that indicate thyroid dysfunction. In that case, your doctor will likely start by palpating your thyroid and ordering a blood test. To palpate your thyroid, your doctor will stand behind you and gently massage the nape of your neck to feel for any enlargement or nodules. Sometimes, your doctor may only need to look at your neck to see that the gland is enlarged. This enlargement is called a goiter and can be in both hyper- and hypothyroidism.
Current recommendations suggest that a thyroid ultrasound is only necessary if a goiter is present or the thyroid feels lumpy. Thus, abnormal thyroid blood tests alone do not indicate a need for an ultrasound.
The primary purpose of a thyroid ultrasound is to detect thyroid cancer. Your doctor may suspect thyroid cancer if you have been exposed to radiation or have thyroid nodules. However, less than 5% of thyroid nodules are cancerous, meaning that most nodules are benign. Furthermore, studies show that people with hypothyroidism are not at a greater risk for thyroid cancer. Other reasons to perform a thyroid ultrasound may include difficulty breathing or swallowing.
How ultrasound works
Ultrasound (also called sonography) creates pictures of your organs using sound waves that bounce off body structures. Unlike other medical imaging studies, ultrasound does not use any radiation, making it safe for you and the operator. An ultrasound technician uses a probe to deliver high-frequency sound waves and gel to glide across your skin’s surface. These sound waves create a live picture of what is going on inside your body. A computer takes the echos that bounce off your tissues to create a real-time image. The process is painless, accurate, and quick.
While ultrasound is very effective, your doctor may sometimes run into difficulty determining if a nodule is benign or cancerous. Therefore, they may need to do an additional procedure called a fine needle aspiration biopsy. Also, an ultrasound cannot determine thyroid function. Therefore, you will need to have a blood test to assess if you have a thyroid condition like hypothyroidism.
How to prepare for an ultrasound
Little preparation is necessary for an ultrasound. If you are concerned about cost, it can help to go through your doctor’s billing department or your insurance carrier to see what an ultrasound will cost. Generally, thyroid ultrasounds are covered by insurance at little to no additional cost to you.
Unlike other imaging procedures, an ultrasound requires no preparation. When you meet your ultrasound technician or doctor on the day of your scan, you will lay flat on a table with your head and neck extended. The health care worker will then apply some gel on your neck and rub the probe over your thyroid. The procedure does not hurt and takes little time.
If abnormalities are on your scan, you may have to return for an additional ultrasound procedure called a fine needle aspiration biopsy. A radiologist usually performs this procedure. The doctor will numb your skin and insert a needle into the area in question (usually a nodule) to pull fluid out to send to a lab. This fluid indicates whether a nodule is benign or cancerous. They may take a few different samples.
Once your doctor finishes with the biopsy, they will apply a small Band-Aid over the area, and you can go about the rest of your day. Unless there are complications, the whole procedure takes about 30 minutes.
What your ultrasound results mean
While you have the test, your ultrasound technician may talk to you about what they see during the exam. However, only your doctor will be able to confirm and diagnose any findings from the test. Here are some of the terms you may hear in your results:
A thyroid gland is about the size of a small plum and has two lobes: left and right. Your ultrasound results will indicate which lobe has abnormalities.
A thyroid nodule is an abnormal clump or growth of cells that creates a lump on the gland. Most are benign, which means they are noncancerous. Your radiologist may discuss the following characteristics to describe your nodules:
Some people have small calcium deposits in thyroid nodules. They tend to show up as bright spots on ultrasound. These calcium deposits can sometimes indicate papillary thyroid cancer, which is the most common type of thyroid cancer. You may see the term “echogenic foci” about microcalcifications.
Do not panic if your doctor orders a thyroid ultrasound. Thyroid cancer is less common than other cancers, and remember, most nodules are benign! Furthermore, an enlarged thyroid gland is often a sign of hypo- or hyperthyroidism instead of a tumor. While a diagnosis of any cancer is devastating, thyroid cancer treatment is quite successful.
A note from Paloma Health
If you are worried about your thyroid function, our at-home thyroid blood test kit gives you an overall understanding of your thyroid function, and if there is a need for further evaluation.