ABSTRACT

Positron emission tomography (PET) and single photon emission computed tomography (SPECT) are major nuclear medicine imaging modalities, which enables the noninvasive (and tomographic) measurement of radioactive tracer (radiotracer) concentration in a living biological system, with the spatial resolution <0.1 g of tissue and temporal resolution <1 min. In particular, PET is most widely used in the tracer kinetic studies because PET has superior spatial resolution, sensitivity, and quantitative accuracy in the measurement of radiotracer concentration.