Isotopes of iodine necessary in tests that require several days of imaging, for example, fibrinogen scan imaging to detect blood clots. Both I-123 and I-125 emit copious low energy Auger electrons after their decay, but these do not cause serious damage (double-stranded DNA breaks) in cells, unless the nuclide is incorporated into a medication that accumulates in the nucleus, or into DNA (this is never the case is clinical medicine, but it has been seen in experimental animal models). Iodine-125 is also commonly used by radiation oncologists in low dose rate brachytherapy in the treatment of cancer at sites other than the thyroid,
Iodine deficiency through a functional iodine test in the form of an iodine skin test. In this test, the skin is painted with an iodine solution: if the iodine patch disappears quickly, this is taken as a sign of iodine deficiency. However, no accepted norms exist on the expected time interval for the patch to disappear, and in persons with dark skin color the disappeance of the patch may be difficult to assess. If a urine test is taken shortly after, the results may be altered due to the iodine absorbed previously in a skin test. Iodine deficiency is treated by ingestion