A nuclear study is a diagnostic procedure that is part of nuclear medicine. It uses radioactive isotopes that bind to receptors or organs in the body. These isotopes can then be detected with the use of a gamma ray camera which detects the radioactive decay in the body. Unlike radiology, which applies ionizing radiation to the patient to image it (such as in an x-ray), nuclear medicine uses radioactivity placed in the body to provide the image to a passive detector.