1. An imaging method comprising: acquiring three-dimensional positron emission tomography time-of-flight line-of-response (TOF-LOR) data, each TOF-LOR corresponding to a line-of-response with time-of-flight spatial localization; slice-binning the TOF-LOR data into a plurality of two-dimensional TOF-LOR data sets based on the time-of-flight spatial localization, at least some of the slice-binned TOF-LOR data corresponding to lines of response that are oblique to the two-dimensional data sets; and reconstructing the two-dimensional TOF-LOR data sets into corresponding image slices defining a three-dimensional reconstructed image, wherein the reconstructing of each two-dimensional TOF-LOR data set includes defining an approximate image as an aggregation of spatial points defined by the TOF-LORs of the two-dimensional TOF-LOR data set and inverse time-of-flight filtering the approximate image to produce the image slice.