Nuclear imaging in medicine uses a small amount of a radioactive substance called a tracer to check organ function and blood circulation. These tests help physicians detect and diagnose disease. They also can show how well treatment is working. Nuclear medicine is a specialty that draws on many disciplines, including chemistry, physics, mathematics, computer technology and medicine.
For a diagnostic nuclear medicine scan, you’ll lie on a padded examination table under a camera that takes a series of pictures over a period of time. The test usually lasts less than an hour. You must remain very still during the procedure to avoid blurring the images.
A Day in the Life of a Nuclear Medicine Technologist
During the procedure, you may drink water to prevent dehydration. Before the scan, you’ll have a medical history reviewed to see whether there are any conditions that could interfere with the procedure or affect its results. A physician will explain the procedure to you and answer any questions you have.
Most diagnostic nuclear medicine tests take advantage of the fact that diseased tissues or body parts handle certain substances differently than normal tissue. For example, a bone scan uses the radioactive tracer technetium-99m bound to a molecule that binds specifically to bone, such as methylene diphosphonate (MDP). As the tracer passes through your body, it releases radiation in the form of gamma rays. The gamma rays are detected by the SPECT or PET scanner and converted to images that reveal how much of the tracer has been absorbed.