1. A positron emission tomography (PET) system, said system comprising: at least one processor programmed to: receive event data for a plurality of scintillation events corresponding to gamma events, the gamma events generated by gamma photons from a region of interest (ROI); cluster the scintillation events based on time to create a plurality of clusters, each cluster corresponding to a different one of the gamma events; determine a classification of the gamma event corresponding to each cluster based on a spatial configuration and a number of each cluster, the classifications distinguishing between single-crystal gamma events and multi-crystal gamma events, wherein the classifications indicate whether gamma energy was deposited in: 1) a single crystal; 2) two adjacent crystals; 3) two non-adjacent crystals; and 4) more than two crystals; generate a first image representation of the ROI using only single-crystal gamma events; generate additional image representations of the ROI corresponding to the classifications; weight each additional image representation based on the classification; and, combine the first image and the weighted additional images to generate the image representation of the ROI.