Diagnostic imaging using radioactive materials.
A thyroid scan and uptake test are nuclear medicine procedures that provide information about the structure and function of the thyroid gland. These tests are commonly used to evaluate thyroid nodules, assess thyroid function, and diagnose certain thyroid disorders.
Thyroid Scan:
Radioactive Tracer Injection: A small amount of a radioactive iodine substance, usually iodine-123 or technetium-99m pertechnetate, is injected into the bloodstream or administered orally. The thyroid gland takes up this radioactive material.
Waiting Period: The patient waits for a certain period to allow the thyroid gland to absorb the radioactive tracer.
Imaging: A gamma camera is used to capture images of the thyroid gland as it accumulates and concentrates the radioactive material. The camera detects the gamma rays emitted by the tracer, creating a visual representation of the thyroid’s structure and function.
Scan Interpretation: The images obtained can reveal the size, shape, and distribution of the thyroid gland. Abnormalities, such as nodules or areas of increased or decreased function, can be identified.
Thyroid Uptake Test:
Radioactive Iodine Ingestion: The patient typically ingests a small amount of radioactive iodine, usually in the form of a pill.
Measurement of Radioactive Uptake: After a specified period, the amount of radioactive iodine taken up by the thyroid gland is measured using a special device called a gamma probe.
Calculation of Uptake Percentage: The percentage of radioactive iodine taken up by the thyroid is calculated, providing information about the thyroid’s ability to concentrate iodine.
Both the thyroid scan and uptake test are useful in evaluating various thyroid conditions.
