radioiodine uptake test


radioiodine

 [ra″de-o-i´o-dīn] any radioactive isotope of iodine; of the nine isotopes, iodine 123, iodine 125, and iodine 131 are the most commonly used in diagnosis and treatment of benign and malignant diseases of the thyroid gland and in scintiscans of organs such as the lung, liver, and kidney. Called also radioactive iodine.radioiodine uptake test one of the most common thyroid function tests; a known quantity of radioiodine is administered and 24 hours later the per cent is calculated that has been absorbed by the thyroid gland. Patients who have recently been exposed to iodine compounds, such as in dietary supplements, contrast media, medications, or antiseptics may not be good candidates for this test.