Before having a nuclear medicine procedure performed, patients are given a radioactive material called an isotope. Isotopes can be injected, inhaled, or swallowed in liquid or capsule form. Once the isotope is inside the body, it travels to the target organs or tissues and gives off gamma rays. Images are then taken of the body with special equipment that can detect the gamma rays. These images are interpreted by a radiologist with special training in nuclear medicine. Various types of equipment are used for nuclear medicine studies depending on the procedure. Gamma probes, stationary gamma cameras, and single photon emission computed tomography (SPECT) cameras.