Nuclear medicine is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear medicine, in a sense, is "radiology done inside out" or "endoradiology" because it records radiation emitting from within the body rather than radiation that is generated by external sources like X-rays. In addition, nuclear medicine scans differ from radiology as the emphasis is not on imaging anatomy but the function and for such reason, it is called a physiological imaging modality. Single Photon Emission Computed Tomography or SPECT and Positron Emission Tomography or PET scans are the two most common imaging modalities in nuclear medicine.
Nuclear medicine imaging uses small amounts of radioactive materials called radiotracers that are typically injected into the bloodstream, inhaled or swallowed. The radiotracer travels through the area being examined and gives off energy in the form of gamma rays which are detected by a special camera and a computer to create images of the inside of your body. Nuclear medicine imaging provides unique information that often cannot be obtained using other imaging procedures and offers the potential to identify disease in its earliest stages.
Using nuclear medicine as a diagnostic tool is a generally painless approach that can provide excellent information to physicians. Some radiotracers are injected, while others you will be asked to either inhale or swallow. These radiotracers contain a small amount of radioactive material that enables doctors to see what is happening at the molecular level when you are examined under a special camera or imaging device.
Using nuclear medicine as treatments like radioactive iodine (I131) therapy or radioimmunotherapy (RIT) has proven to help fight against certain cancers, heart problems, and other diseases. In adults, nuclear medicine can be used for the following: