Radioactive Iodine Thyroid Clinic
We provide comprehensive thyroid care with our nuclear medicine thyroid clinic available in the office, Minuscule doses of radioactive iodine can be used to diagnose problems with thyroid function. Larger doses of radioactive iodine can be used to treat over active thyroid function and thyroid malignancy. The office is licensed to provide diagnostic and treatment doses of radioactive iodine. VISITING HOUSTON? Click here for details about preparation for your trip here for radioactive iodine treatment.
DIAGNOSIS OF HYPERTHYROIDISM: the iodine I-123 uptake test
*Frequently Asked Questions about I-123 thyroid scan/uptake testing* print/download a copy
Small doses of radioactive iodine (I-123) can be used to evaluate why a patient has hyperthyroidism with an "uptake test". Your doctor may order this test in order to differentiate high-uptake hyperthyroidism versus low uptake causes of hyperthyroidism. This testing is done in a simple two-day procedure. The thyroid is essentially the only gland in the body that metabolizes iodine and converts it to thyroid hormone. If a fixed dose of radioactive iodine I-123 is swallowed by a patient, we can determine what percentage of that I-123 is used by the thyroid. The higher the percentage, the more intrinsically overactive the thyroid is acting.
Preparing for the uptake test:
Women may have a pregnancy test performed prior to testing. You should inform the doctor if you have recently taken large doses of iodine, seaweed, kelp or had a CT scan with IV contrast within the last month. Also you must remain off drugs commonly used to treat hyperthyroidism such as methimazole or PTU for at least 7 days prior to the treatment,
Day 1: Come to the office swallow a small capsule of low-dose I-123 in the morning. 4-hours later a scan of the thyroid is completed. The scan takes 5-10 minutes while you are seated comfortably.
Day 2: 24 hours later another 5-10-minute scan is completed. Your results are available immediately for treatment decisions.
TREATMENT OF HYPERTHYROIDISM OR THYROID MALIGNANCY: Iodine I-131
*Frequently Asked Questions about thyroid I-131 treatment* print/download a copy
Radioactive iodine treatment with I-131 is one good option to treat high-uptake-hyperthyroidism and sometimes a required treatment for thyroid malignancy. radioactive iodine treatment (RAI) is based on the biology that the thyroid actively accumulates iodine, using it to produce thyroid hormones. Radioactive I-131 is like the iodine found in foods such as fish, seaweed, and iodized salt, except that it releases an electron, or beta particle, which creates its treatment action. For use in treatment, the RAI is given as a capsule. It is absorbed quickly by the stomach and intestines, then carried in the bloodstream to the thyroid, where it is taken up by the thyroid gland. While in the thyroid gland, the RAI disrupts the function of some of the thyroid cells - the more radioactive iodine given, the more cells cease to function.
Preparing for the treatment:
Women must have a pregnancy test performed prior to testing. You should inform the doctor if you have recently taken large doses of iodine, seaweed, kelp or had a CT scan with IV contrast within the last month. Also you must remain off drugs commonly used to treat hyperthyroidism such as methimazole or PTU for at least 7 days prior to the treatment. You will be scheduled to come to the office in the morning to swallow a capsule of radioactive iodine, and then you may go back home
Thyroid cancer patients who recently had thyroid surgery:
Women must have a pregnancy test performed prior to testing. You should inform the doctor if you have recently taken large doses of iodine, seaweed, kelp or had a CT scan with IV contrast within the last month. The remaining thyroid tissue after thyroid surgery must be prepared to be "hungry" for the iodine treatment by one of these pathways: WITHDRAWAL PATHS: Path 1 or Path 2 or THYROGEN PATHS: Path 3 or Path 4 or Path 5
Side Effects of iodine treatment
Radioactive iodine treatment has few side effects, and these occur infrequently. A sore throat may occur a few days after the treatment, which can be treated with acetaminophen. Rarely, the salivary glands may swell, which is caused by the iodine and not the radioactivity. Sucking hard sour candies for a few days can prevent this. Mild nausea may develop for a few hours after the iodine is taken, so it is best not to eat two hours before and two hours after the iodine administration. There are specific precautions for hyperthyroid patients and specific precautions for thyroid cancer patients to take after receiving I-131.