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How Nuclear Medicine Works

Nuclear medicine allows a physician to visualize how the body is functioning at the molecular and cellular level. The physician uses radiotracers or radiopharmaceuticals to introduce very small amounts of radioactive materials into the body. These materials may be injected into the patient’s bloodstream, inhaled or swallowed. 

The radiotracer travels to a specific area of the body and gives off a small amount of energy in the form of gamma rays. Special cameras called gamma cameras detect radiopharmaceuticals in the body and send very precise pictures to a computer. 

In planar imaging, the gamma camera remains stationary creating a two-dimensional (2D) image. Conversely, in single photon emission computed tomography (SPECT) imaging, the gamma camera rotates around the patient and produces slices of the body similar to those produced by a CT scan. This produces a three-dimensional (3D) image which can then be “fused” to CT images to produce both anatomic and molecular imaging data.

These combined images allow our SLUCare physicians to assess how the body is functioning and measure various chemical and biological processes. Our doctors then use this information to diagnose and treat conditions such as cancer, heart disease, brain disease and more. 

Meet Our Nuclear Medicine Specialists