Evaluation of an Energy-Based Method for Scatter Correction in Positron Emission Tomography

Scatter is an important concern in 3D PET imaging. We have previously proposed an energy-based method for effectively and efficiently correcting scatter by applying energy-based weighting factor to the detected events. The weighting factor, which represents the probability that an event with the specific detected photon energies is unscattered, can be obtained a priori due to its observed weak dependence on the exact distributions of the activity concentrations and attenuation coefficients for similarly sized subjects. Because the method involves applying simple weightings to individual events, it requires minimal computations and yet was observed to be surprisingly effective in our initial study. In this work, we conduct extensive simulation studies to qualitatively and quantitatively evaluate the effectiveness of the proposed scatter correction method. Our findings again confirm the effectiveness of the proposed scatter-correction method when applied to the NEMA, and NEMA-like, body phantoms.