Optimization of PET system design for lesion detection

Traditionally, the figures of merit used in designing a positron emission tomography (PET) scanner are spatial resolution, noise equivalent count rate, noise equivalent sensitivity, etc. These measures, however, do not directly reflect the lesion detectability using the PET scanner. Here the author proposes to optimize PET scanner design directly for lesion detection. The signal-to-noise ratio (SNR) of lesion detection can be easily computed using the theoretical expressions that the author has previously derived. Because no time-consuming Monte Carlo simulation is needed, the theoretical expressions allow evaluation of a large range of parameters. The PET system parameters can then be chosen to achieve the maximum SNR for lesion detection. The simulation study shown in this paper was focused on a single ring PET scanner without depth of interaction measurement. It can be extended to multiring (two- or three-dimensional) PET scanners and detectors with depth of interaction measurement.