Systems, devices and methods of reconstructing an image from a positron emission tomography scan that may include detecting a plurality of photons selected from scattered photons and unscattered photons by a plurality of detectors, identifying a time interval for each of the plurality of photons by a processing device, matching each of the plurality of photons into a plurality of pairs of coincident photons based upon a substantially simultaneous time interval identified by the processing device, measuring an energy produced by each of the plurality of photons by the plurality of detectors, determining a scattering angle for each pair of coincident photons from an annihilation point relative to the position of the plurality of detectors by the processing device based on the energy produced and reconstructing an image using a reconstruction algorithm, wherein the reconstruction algorithm uses the scattering angle of each pair of coincident photons.