Medical Imaging

Nuclear Medicine > Exams & Procedures > Whole Body Iodine Scan

This test detects and follows up tumor distribution from thyroid cancer.

There are two versions of this test. One involves the administration of a high dose of radioactive iodine used to treat thyroid cancer. The other involves the administration of a small amount of radioactive iodine that will be used to follow the progress of thyroid treatment. In either case, pictures are taken between two and ten days after tracer administration.

Preparation

  • Many medications interfere with the results of this test. Please talk to your doctor about which medications to stop for this test and when to stop taking them.
  • Products high in iodine should not be eaten from one week before the test until the test is complete. Excessive iodine in the body falsely lowers the results of this test. Do not eat or drink products that contain shellfish (lobster, crab, shrimp, etc); kelp products or supplements, or cough medicines for at least one week
  • You should have no X-ray tests that use an iodine-based contrast dye within two to four weeks of this test.
  • Bring a list of all medications and supplements you take. This includes vitamins, herbal remedies, and holistic medications.
  • Do not bring children or pregnant women with you to the department. We do not want to expose them to unnecessary radiation.
  • Any of these procedures is subject to change according to the nuclear medicine physician. The duration of the tests is a rough estimate. Please be aware that the time may be lengthened if a scan has to be repeated, if emergency cases are brought to the department or due to unforeseen circumstances.

About the Procedure

  • The procedure takes about one hour for pictures.
  • A technologist will briefly explain the test to you and try to answer any questions you may have about the procedure.
  • A technologist will ask you a few questions about your medical history and medications.
  • Version 1: Your doctor will give you a radioactive iodine therapy to kill off any thyroid tissue and you will return for pictures 10 days later.
  • Version 2: The physician will give you radioactive iodine to follow the progress of thyroid treatment and you will return for pictures two to ten days later.
  • You will be asked to lie down on an imaging bed.
  • Cameras will be positioned above and below you.
  • Pictures will be taken of your whole body for about 30 minutes.
  • Another picture will be taken using a zoom lens for about 10 minutes.