What is a thyroid uptake and scan test?

A thyroid scan is a type of nuclear medicine imaging, while a thyroid uptake is a measurement of thyroid function that does not use imaging, according to RadiologyInfo.org. A thyroid scan provides information regarding the size, shape and position of the thyroid gland, while a thyroid uptake evaluates function.

These tests are used to determine if the thyroid is working properly, to diagnose problems with the thyroid gland such as cancer or an overactive thyroid, assess nodules present on the gland or evaluate changes to the gland following various treatments, according to RadiologyInfo.org. Both procedures are typically performed on an outpatient basis.