What is nuclear medicine?
Nuclear medicine is a specialized area of radiology that uses very small amounts of radioactive materials, or radiopharmaceuticals, to examine organ function and structure. Nuclear medicine imaging is a combination of many different disciplines, including chemistry, physics, mathematics, computer technology, and medicine. This branch of radiology is often used to help diagnose and treat abnormalities very early in the progression of a disease, such as thyroid cancer.
Because X-rays pass through soft tissue, such as intestines, muscles, and blood vessels, these tissues are difficult to visualize on a standard X-ray, unless a contrast agent is used, which allows the tissue to be seen more clearly. Nuclear imaging enables visualization of organ and tissue structure as well as function. The extent to which a radiopharmaceutical is absorbed, or "taken up," by a particular organ or tissue may indicate the level of function of the organ or tissue being studied. Thus, diagnostic X-rays are used primarily to study anatomy, whereas nuclear imaging is used to study organ and tissue function.
How are nuclear medicine scans done?
Nuclear medicine scans may be performed on many organs and tissues of the body. Each type of scan employs certain technology, radionuclides, and procedures.
A nuclear medicine scan consists of three phases: tracer (radionuclide) administration, taking images, and image interpretation. The amount of time between administration of the tracer and the taking of the images may range from a few moments to a few days, depending on the body tissue being examined and the tracer being used. Some scans are completed in minutes, while others may require the patient to return a few times over the course of several days.