Radioactive iodine uptake (RAIU)

Radioactive iodine uptake (RAIU) is a diagnostic test that measures how much iodine the thyroid gland absorbs from the bloodstream. Since the thyroid needs iodine to produce hormones, this test helps evaluate its function and identify conditions like hyperthyroidism or thyroid nodules. During the test, a small amount of radioactive iodine is given, and after a few hours, a detector measures how much iodine the thyroid has taken up. The results indicate whether the thyroid is overactive, underactive, or functioning normally, aiding in accurate diagnosis and treatment planning.