Introduction to Nuclear Medicine Nuclear medicine is a medical specialty that uses small amounts of radioactive material to diagnose and treat diseases. The scientific and technical concepts related to nuclear medicine involve the use of radioactive isotopes, which emit gamma rays or positrons, to create images of the body and to deliver targeted therapy to specific cells or organs. Radiation Used in Nuclear Medicine The type of radiation typically exploited in most nuclear medicine procedures is gamma radiation. Gamma rays are a type of electromagnetic radiation that can be used to create images of the body, such as in a gamma camera or a PET scan. Positrons, which are the antimatter counterpart of electrons, can also be used to create images, such as in a PET scan. Patient Preparation for Nuclear Medicine Procedures Patients are typically prepared for nuclear medicine procedures by being given a small amount of a radioactive material, called a radiopharmaceutical, to swallow