What to Expect During a Thyroid Ultrasound
For most ultrasound exams, you are positioned lying face-up on an examination table that can be tilted or moved.
A clear water-based gel is applied to the area of the body being studied to help the transducer make secure contact with the body and eliminate air pockets between the transducer and the skin. The sonographer (ultrasound technologist) or radiologist then presses the transducer firmly against the skin and sweeps it over the area of interest.
The sonographer or radiologist is often able to review the ultrasound images in real-time as they are acquired and you can be released immediately. There may be an occasion, however, where you are asked to dress and wait while the ultrasound images are reviewed.
This ultrasound exam is usually completed within 30 minutes.
Most ultrasound examinations are painless, fast and easy.
There is usually no discomfort from pressure as the transducer is pressed against the area being examined.
If scanning is performed over an area of tenderness, you may feel pressure or minor pain from the transducer.
You will need to extend your neck to gain appropriate access, which may be mildly uncomfortable.
Once the imaging is complete, the gel will be wiped off your skin.
After an ultrasound exam, you should be able to resume your normal activities within a few hours.
Limitations of a Thyroid Ultrasound
If a lump is detected on ultrasound within the thyroid gland, the radiologist may not be able to distinguish between benign and malignant lumps with complete certainty. A fine needle biopsy and review of tissue under a microscope is often necessary, while in some cases surveillance and a repeat sonogram after a few months looking for stability may suffice.
It is not possible to determine thyroid function (underactive, overactive, or normal) with ultrasound. For that determination, your doctor may order a blood test or a radioactive iodine uptake test.