What does a thyroid scan do?

Thyroid scan: It's a nuclear medicine scan use to evaluate how well your thyroid is working. The result will give information on the size, shape, location and the overall activity of the gland. It can also tell you if a thyroid nodule is functioning or non-functioning and help your doctor determine whether a nodule biopsy is needed. More info with the link below: http://www.Webmd.Com/a-to-z-guides/thyroid-scan.

ANATOMY & FUNCTION: A thyroid scan provides info on the anatomy and function of the gland - size, location, mass lesion (cold or hot nodule), and overall qualitative iodine uptake. The quantitative iodine uptake is done by a thyroid probe to differentiate hypothyroid from hyperthyroid gland. A cold nodule = decreased iodine uptake & is suspicious of cancer. Hot nodule = increased iodine uptake = benign adenoma.

Thyroid function: Thias scan measures the uptake and/or the distribution of either iodine (or a different tracer). It will tell if one has an overactive/under active thyriod as well as give information on whether a nodule is overactive or underactive.

If hyperthyroidism: If you are having a diagnostic dose of i-123 (usually 200 microci), you should stop taking anti-thyroid medications (methimazole and ptu) and make sure you didn't have iodine-based IV contrast (used in ct scans) in the prior 6-8 weeks. For a diagnostic study a low-iodine diet is not require, unless you are going to received i-131 treatment shortly after the test.

Supply information: Let them know had CT scan, surgeries or treatments using iodinated contrast material within the last two months, taking medications or ingesting other substances that contain iodine, including kelp, seaweed, cough syrups, multivitamins,heart medications. any allergies to iodine, medications and anesthetics.pregnant or breastfeeding.Isotope used either Iodine 123 ingested or Technetium 99m IV.

Resume daily life: If thyroid scan was performed with iodine 123 or technetium 99m pertechnetate involves a low amount of radiation. The half lives are short enough (13 and 6 hours) that most irradiation will have dissipated by 24-48 hours. Whatever i123 does not accumulate in thyroid gland are excreted via kidneys, saliva, and sweat. Tc 99m usually exits via kidneys, GI tract, and saliva. I131 involves higher dose.

Follow up with MD: What was the reason for the thyroid scan? Discuss what the results are with your physician to determine whether or not you need treatment of any thyroid dysfunction, if any.