Nuclear medicine involves injecting radioactive tracers and using gamma cameras to image how the inside of the body is working. A small amount of radioactive medication is administered and detected as it emits radiation, allowing special cameras to take pictures of organs and physiological processes. Different tracers can image various organs depending on where they accumulate. Single photon emission computed tomography (SPECT) improves on planar nuclear medicine imaging by using gamma camera rotation to generate 3D, cross-sectional images of the body.