A thyroid scan uses a radioactive tracer and a special camera to make a picture of the thyroid gland. The radioactive tracer used in this test is usually iodine or technetium. A thyroid scan is done to help find problems with the thyroid gland.
A normal thyroid scan shows a small butterfly-shaped thyroid gland about 2 in. (5 cm) long and 2 in. (5 cm) wide with an even spread of radioactive tracer in the gland.
An abnormal thyroid scan shows a thyroid gland that is smaller or larger than normal. It can also show areas in the thyroid gland where the activity is less than normal (cold Reference nodules Opens New Window) or more than normal (hot nodules). Cold nodules may be related to thyroid cancer.
A whole-body scan will show whether iodine is in bone or other tissue (iodine uptake) after the thyroid gland has been removed for cancer. The whole-body scan can check to see if cancer has spread to other areas of the body.
|By:||Reference Healthwise Staff||Last Revised: Reference May 31, 2011|
|Medical Review:||Reference E. Gregory Thompson, MD - Internal Medicine
Reference Matthew I. Kim, MD - Endocrinology