Thyroid Uptake and Scan

If you have a thyroid disease, your doctor may order a nuclear medicine imaging test known as a thyroid uptake and scan. This actually consists of two tests performed together, one being the thyroid uptake and the other the thyroid scan. The purpose of these tests is to find out how your thyroid is functioning and to see if your thyroid has any abnormalities. This information will help your doctor greatly in knowing what is wrong with your thyroid and what would be the best treatment options.

What to Expect with a Thyroid Uptake and Scan

I have two autoimmune thyroid diseases, Hashimoto's and Graves, and have had two thyroid uptake and scans done so far. Your uptake and scan may not be exactly like mine have been, but it should be similar to the following description.

First, you will be given a very small dose of radioactive iodine for your thyroid to absorb. My dose was a little pill, but there are also doses given as liquids, shots, or even ones you inhale. I was told to not eat before taking the pill to ensure maximum absorption of the iodine. I went to the radiology department at our local hospital to be given the radioactive iodine. When I got there, they had me sit in a chair while they placed a probe in front of my neck and by my thigh to check my levels before taking the iodine. The pill was then brought in. This part freaked me out a little bit because the pill was inside a container that was in a lead container which was inside another container with little radioactive symbols on it. Talk about making you feel like you were taking something dangerous. I asked about it and the medical staff assured me that the reason for all the containers was to protect those that work with the radioactive iodine on a regular basis from having constant exposure to it and that the low dose with a short exposure, like me taking the pill, was quite safe. So I took the little radioactive pill, joking about how I was going to start glowing. After taking the pill, my body needed to absorb the iodine for 24 hours, so I headed home.

I went back to the radiology department the next morning, where they had me sit in the chair again while they checked my levels with the little probe again. After they were sure my body had absorbed enough radioactive iodine, I was ready for the thyroid scan. For the scan, I had to lie very still on a curved table with my neck on a round pillow and my head tipped back. The machine had a large camera that rotated slowly around my neck while it took images of my thyroid. The scan took about half an hour. I actually started to doze off as it was quite relaxing with the dim lighting and the room being very quite except for a soft humming coming from the machine. After the scan was done, I went home again.

The next morning, I went to the radiology department one last time so they could check my levels with the probe again. After that, the thyroid uptake and scan were done. I didn't notice and side effects or adverse reaction to the uptake or scan.

What a Thyroid Uptake and Scan Will Tell Your Doctor

The results of the uptake will tell your doctor how your thyroid is functioning. If your thyroid is functioning slowly, as in hypothyroidism, it will absorb less of the radioactive iodine than it should. If your thyroid is overactive, as in hyperthyroidism, it will absorb more of the radioactive iodine than it should.

The results of the scan will let your doctor see the size and shape of your thyroid. This will allow your doctor to know if your thyroid is enlarged, as with a goiter, or has an abnormal shape, as with nodules or tumors. The results of the scan will also let your doctor know if there are any hot or cold nodules in your thyroid. A hot nodule is when an area of your thyroid is producing too much thyroid hormone. If you have a hot nodule, this area will absorb more radioactive iodine than the rest of your thyroid. A cold nodule is when an area of your thyroid isn't producing any thyroid hormone. If you have a cold nodule, this area of your thyroid won't absorb any of the radioactive iodine.

Benefits of Having a Thyroid Uptake and Scan

The combination of the results of your thyroid uptake and scan, along with blood tests to check your thyroid hormone levels, will enable your doctor to have a clear picture of what is going on in your thyroid and then be able to make a good decision on the best treatment for your specific diagnosis.

Further Reading:

Thyroid Tests: Thyroid Ultrasound

Hashitoxicosis Signs and Symptoms - Hashimoto's Thyroiditis with a Twist

Hyperthyroidism: Signs and Symptoms

Methimazole (Tapazole) - Signs and Symptoms of Overmedication and Side Effects

Synthetic Vs. Natural Thyroid Medication: Synthroid Vs. Armour Thyroid Medicine

Side Effects of Synthroid - Signs that Your Thyroid Medicine is Making You Sick

Thyroid Hormone Replacement: Signs and Symptoms of Overmedication (Overdose)

Thyroid Disease: Could You Have It?

Sources:

RadiologyInfo.org - Thyroid Scan and Uptake

EndocrineWeb - Thyroid Cancer

EndocrineWeb - Hyperthyroidism

EndocrineWeb - Thyroid Gland Function