Nuclear medicine thyroid scan
Special information on this examination
The distribution of intravenously injected activity in the thyroid gland is detected in form of emitted gamma radiation by a special thyroid gamma camera, and then high-resolution two-dimensional images (=thyroid scintigram) of the well-functioning thyroid tissue are taken.
Indications: detection of cold (= storing little radiation) or hot (= storing much radiation) thyroid nodules and untypically lying thyroid tissue. Evaluation of the overall metabolic activity of the thyroid tissue (quantitative analysis).The substance applied: technetium 99 m. Activity: about 37 to 74 MBq in adults, about 4 to20 MBq in children. The radioactive material will be injected into a vein.
As a rule, medications that affect the thyroid should not be taken for at least two weeks before the examination after a previous consultation with the doctor. Iodine-containing medications or iodine tablets should also be discontinued upon agreement with the doctor at least four weeks before the examination.
If you underwent X-ray or computed tomography, requiring an intravenous contrast media, within a shorter period of time than three months before the examination, the iodine found in the contrast media can block the thyroid, so that it cannot be depicted on a scintigram. In this case, you should ask your referring physician to consult us.
Special additional examination:
Thyroid suppression scintigraphy
Performed as the normal thyroid scintigraphy, however, after a medicamenous preparation with a thyroid hormone that lasts one to three weeks (depending on the type of the hormone compound).
Indications for that: suspicion of hot thyroid nodules (autonomy).
On the average, the examination lasts up to an hour. The thyroid scintigraphy is often combined with an ultrasound scan (sonography) of the thyroid gland. You should tell us about that when you call us to make an appointment, so that we can plan enough time for the examination.