1. A method for reducing, in an image, motion related imaging artifacts, said method comprising: obtaining a single image volume of a subject using a computed tomography (CT) imaging system; obtaining a plurality of projection data of the subject using a positron emission tomography (PET) imaging system; calculating a plurality of initial consistency values using the CT image and the plurality of PET projection data, wherein each consistency value represents at least one of a sum or row-sum of all emission data acquired in a view and is view angle independent; generating a plurality of attenuation-corrected PET images; generating a PET motion correction including a series of transformation matrices; utilizing the combination of transformation matrices and initial consistency values to generate transformed CT image volumes to match the plurality of PET projection data; calculating updated consistency values using the transformed CT image volumes; using objective functions to iteratively determine changes in the updated and initial consistency values; and generating a final attenuation-matched PET reconstruction and motion correction if the determined change is less than a predetermined threshold, and if the determined change is not less than the predetermined threshold, generating a revised set of attenuation corrected PET images using the transformed CT image volumes, and using objective functions to iteratively determine changes in the updated and initial consistency values.