Although the majority of thyroid growths, or nodules, are benign and not cause for concern, once a nodule has been detected, a physician will want to gather additional information before proceeding with treatment recommendations. At this point, a thyroid ultrasound will be ordered to best determine a proper plan of action.
A thyroid or parathyroid ultrasound is a common test that utilizes sound waves to produce an image of the thyroid gland. This procedure is quite common and completely painless.
An ultrasound is administered by a radiologist or ultrasound technician. The entire test takes around 10 minutes and provides immediate results, which are then interpreted by your doctor and radiologist. The ultrasound may be performed in a hospital or in an outpatient facility.
- After removing your shirt, you will lie on your back; be sure to remove any necklaces or other accessories that might block access to your throat.
- The technician places a pillow or pad under your neck to tilt your head and expose your neck.
- A lubricant jelly is applied to the skin on your neck; it may be cold at first.
- The technician glides the probe, or transducer, over the area of your neck in which your thyroid gland is located.
- Sound waves are transmitted through the skin into the thyroid and surrounding tissues.
- Sound waves bounce back like an echo, producing images on a screen.
- The handheld probe detects the reflections and translates them into a picture of your thyroid gland.
Purpose of an Ultrasound
A thyroid ultrasound may be performed if your thyroid function test comes back abnormal. It can also be used to check an overactive or underactive gland. If your doctor feels a growth on the thyroid when examining your neck, an ultrasound will likely be ordered. Ultrasounds are used to:
- Identify thyroid cysts, nodules, tumors, or other abnormalities
- Discriminate between various types of thyroid lumps
- Determine the number of growths
- Pinpoint the precise location of nodules
- Delineate the boundaries of growths
- Distinguish between a solid nodule and a fluid-filled sac, or cyst
- Diagnose an enlarged thyroid gland
- Track the size of the thyroid during treatment
- Search for enlarged parathyroid glands caused by disease
- Detect goiter, which is swelling of the thyroid gland
There are certain characteristics found on an ultrasound that indicate a benign, or harmless, nodule.
- Sharp edges around the entire nodule
- Nodule is filled with fluid rather than live tissue as with a cyst
- No blood flows through the nodule
- Multiple nodules found throughout the thyroid
The fine needle aspiration biopsy, or FNA, is often the first test performed following a thyroid or parathyroid ultrasound. It is used to determine whether a nodule is benign or malignant.
If your ultrasound shows no abnormalities, you may not need additional testing or care.