What is SPECT?
SPECT is a nuclear medicine technique in which tomographic (cross-sectional) images of the spatial distribution and amount of accumulation of a single gamma ray emitting radiotracer in the body are created. It also requires the use of a collimator, which generally results in lower sensitivity and poorer image quality compared to PET. Furthermore, SPECT requires the use of radioisotopes that emit single gamma rays, which are usually metallic elements that are difficult to incorporate into biologically important compounds. SPECT/CT scanners ( Figure 3-3 ) are most often employed for SPECT imaging to provide coregistered molecular and structural images.