WHAT YOU NEED TO KNOW: What do I need to know about a thyroid scan and uptake test? A thyroid scan and uptake test are nuclear medicine tests done to examine your thyroid gland. During a thyroid scan, a small amount of radioactive tracer is given to create pictures of your thyroid. The pictures show the size, shape, and position of your thyroid. A thyroid scan may also show if there are any lumps in your thyroid. During an uptake test, a radioactive iodine tracer is given to show how well your thyroid works. The amount of radioactive iodine taken up by your thyroid will be measured. How do I prepare for a thyroid scan and uptake test? Your healthcare provider will talk to you about how to prepare for these tests. You will need to stop using supplements or medicines that contain iodine. You may also need to follow a low-iodine diet for about a week before these tests. Your healthcare provider may tell you not to eat or drink anything for several hours before the tests. He will also tell you what medicines to take or not take on the day of your tests. You may be told not to wear jewelry or anything made of metal during the tests. What will happen during a thyroid scan and uptake test? - For a thyroid scan, you will be given a radioactive tracer in the form of a liquid, pill, or injection. If you will also have an uptake test, you will be given radioactive iodine in the form of a pill or liquid. The scan will take place from 6 to 24 hours after you take the iodine in liquid or pill form. If you received an injection, the scan will take place about 30 minutes after the injection. The uptake test will be done from several hours to 24 hours after you take the radioactive iodine.
- During the thyroid scan, you will lie on an exam table. Your head will be tipped backward so your neck will be extended. A camera will take several pictures of your thyroid from different angles. You will need to remain very still while the camera takes the pictures. During the uptake test, you will be sitting. A probe will be placed near your neck to take measurements of the amount of iodine taken up by your thyroid. You may need 2 measurements taken at different times.
What will happen after a thyroid scan and uptake test? You will need to drink plenty of liquids after your thyroid scan and uptake test. This will help flush the tracer out of your body. Ask your healthcare provider how much liquid to drink each day and which liquids are best for you. What are the risks of a thyroid scan and uptake test? If you had an injection of radioactive tracer, you may have mild pain and redness at the injection site. Women who are pregnant or breastfeeding should not have these tests. The fetus or baby can be exposed to a small amount of radiation from the tracer used during these tests. |