The thyroid scan is used to determine the size, shape and position of the thyroid gland. The thyroid uptake is performed to evaluate the function of the gland.

A whole-body thyroid scan is typically performed on people who have or had thyroid cancer.

A physician may perform these imaging tests to:

• determine if the gland is working properly
• help diagnose problems with the thyroid gland, such as an overactive thyroid gland, a condition called hyperthyroidism, cancer or other growths
• assess the nature of a nodule discovered in the gland
• detect areas of abnormality, such as lumps (nodules) or inflammation
• determine whether thyroid cancer has spread beyond the thyroid gland
• evaluate changes in the gland following medication use, surgery, radiotherapy or chemotherapy