ABSTRACT
This chapter discusses radionuclides, gamma-ray detection, and aspects of the two major types of imaging in nuclear medicine, positron emission tomography (PET) and single-photon emission computed tomography (SPECT). In nuclear medicine, radionuclides that are of use are those that undergo either positron decay or gamma decay. Therefore, like X-ray applications, dosage in nuclear medicine must be kept to a minimum but must be high enough to produce useful images in scan duration of reasonable length. A further advancement of nuclear medicine technology was brought about with the introduction of the gamma camera. Using SPECT, quantification of radionuclide concentration is typically not possible due to poor sensitivity. Nonetheless, PET finds particular utility in diagnosing cancer and studying organ function. The chapter also discusses event detection, image reconstruction and uses of PET. In both SPECT and PET, images are reconstructed using filtered back-projection and the quality of images depends on some of the same parameters.
