Radionuclide Health Dictionary

A diagnostic technique based on detection of radiation emitted by radioactive substances introduced into the body. Substances are taken up to different degrees by different tissues, allowing specific organs to be studied. For example, iodine is taken up mainly by the thyroid gland, so by “tagging” a sample of iodine with a radioactive marker (radionuclide), the uptake of iodine can be monitored to investigate the functioning of the gland. A radionuclide is swallowed or injected into the blood and accumulates in the target organ. It emits radiation in the form of gamma radiation, which is detected by a gamma camera to produce an image. Cross-sectional images (“slices”) can be obtained using a computer-controlled gamma camera that rotates around the patient. This specialized form of radionuclide scanning is known as (single photon emission computed tomography). Moving mation on blood flow, the movement of the heart walls, the flow of urine through the kidneys, and bile flow through the liver.

Radionuclide scanning is a safe procedure, requiring only minute doses of radiation that are excreted within hours. The radionuclides carry virtually no risk of toxicity or hypersensitivity.... radionuclide scanning

(PRRT) a type of radiotherapy used to treat neuroendocrine tumours (NETs; see neuroendocrine system). A *radionuclide is combined with a relevant *peptide to create a so-called radiopeptide, which is injected into the patient’s bloodstream. Because NETs have an overexpression of peptide receptors, the radiopeptide binds to the tumour, delivering a high dose of radiation directly to the cancer cells. The chief merit of PRRT is this ability to target delivery of radionuclides for highly localized treatment. A similar technique, using a gamma emitter as the radionuclide, can be used for locating and imaging NETs.... peptide receptor radionuclide therapy