The thyroid is a small gland located in the front of the neck that produces hormones regulating metabolism. If your clinician’s physical examination and/or preliminary testing finds issues suggesting your thyroid may have enlargement, abnormal positioning, inflammation, goiter, lumps, nodules or metabolic irregularities, he or she may order a nuclear medicine thyroid scan to determine your thyroid’s shape, size and position, and assess how well it is functioning.
Unlike most static imaging methods, nuclear medicine scans provide a combination of both anatomical and functional information from a single test, enabling patients to avoid less-detailed exploratory surgery and its related risks. Nuclear medicine has the capacity to measure molecular activity, enabling doctors to discover diseases in their earliest stages and help monitor the effectiveness of treatment going forward.
A nuclear medicine thyroid scan is a painless, noninvasive test wherein a small amount of radioactive iodine, known as a radiotracer, is introduced to the thyroid via injection, capsule or inhalation. The thyroid absorbs the radiotracer, allowing your RAI radiologist to evaluate 3D images captured by a computer-assisted gamma camera to evaluate its size and shape, functional efficiency and hormone production. This test can determine if there is thyroid enlargement (goiter), lumps, cysts, swelling, cancer, under-activity (hypothyroidism), over-activity (hyperthyroidism) and other issues.
The nuclear medicine thyroid scan typically takes 30 minutes or less. The radiotracer will flush from the body painlessly over the next few hours or days. Exposure to ionizing radiation is low, especially when compared to the benefits of a speedy and accurate diagnosis – however, women who may be pregnant should avoid this test. Most people can resume normal activities and eating habits immediately afterward.
All results are interpreted by an RAI radiologist who subspecializes in nuclear medicine, and will share and discuss findings with your clinician to help stage treatment if required.