ABSTRACT
The nuclear medicine imaging technique provides visual information on the distribution of radioactive agents within the body. In all imaging problems, the ability to detect a small lesion or a lesion in the presence of other structures varies as a function of four basic parameters, namely, spatial resolution, object contrast, count density, and the lesion size. While spatial resolution varies primarily as a function of the physical characteristics of the imaging device, the object contrast and lesion size are defined by the basic properties of the lesion-organ system. Count density, on the other hand, is dependent upon the characteristics of the imaging device as well as the lesion organ system. It will be the purpose of this chapter to discuss the effect of these parameters on lesion detection. In addition, a summary of various single photon imaging devices currently available will be presented.
