Abstract
Stable and radioactive isotopes are used extensively in diagnostic and therapeutic medical applications including studies of human body composition, energy balance, protein turnover, and metabolism. ‘Physics heal thyself: isotopes in medicine’ shows how ionizing radiation is key to a host of medical imaging techniques with radioactive isotopes widely used to target and kill cancer cells. Enriched isotopes are used as biological tracers; doubly labelled water in the diagnosis of type 2 diabetes; and 13C-labelled urea in diagnosing stomach and duodenal ulcers. Medical uses of ionizing radiation are manifold including X-ray imaging, radiotherapy with external X-ray beams, brachytherapy, targeted radionuclide therapy, single photon emission computed tomography, and positron emission tomography.