Radiation detectors in medicine

Radiation detectors are used as the sensing elements in medical imaging modalities, such as radionuclide scans (nuclear medicine) in X-ray imaging, and as monitors for radiation exposure. The simplest devices - usually gas filled ionization chambers are used to monitor relatively high fluxes. In the medical imaging situations, the detectors are usually position sensitive devices, with spatial resolutions ranging from a fraction of a millimeter to a few millimeters. The types of detectors used include gas filled MWPC and other configurations, scintillation counters using high Z inorganic crystals, Silicon and Germanium crystalline semiconductors, as well as Amorphous Selenium and Silicon layers. 25 figs