Nuclear medicine imaging uses very small amount of radioactive materials, called radio- pharmaceuticals to aid disease diagnosis. Radiopharmaceuticals are distributed throughout the blood stream and are attracted to specific organs, such as the brain, bones, or other tissues. They emit gamma radiation, which is detected and counted by a gamma camera. The processed data over time provides functional and anatomical information about the part of the body being imaged. The gamma camera system at the Neuroradiology Department of the National Neuroscience Institute is a dual head scanner.