1. A medical imaging system, comprising: one or more processors programmed to: receive a first image contrasting regions of tissue with a distinct radiotracer accumulation probability; generate a constraint map based on the regions of tissue with the distinct radiotracer accumulation probability; receive raw image data; redistribute the received raw image data by subdividing a low resolution voxel of the acquired image raw data into corresponding higher resolution voxels of the first image and reassigning values of the subdivided low resolution voxel to the higher resolution first image voxels based on the constraint map; and reconstruct the redistributed raw image data into a second image; and a display device which displays the reconstructed second image.