research, we improve upon a class of MAR algorithms based on sinogram in-painting.1–13 Sinogram in-painting methods are vulnerable to the misrepresentation of anatomical edges that overlap the metal traces. Various algorithms have tried to address this problem.3–8,12,13 We segment regions contaminated by metal artifacts from anatomical structures in the originally reconstructed image, henceforth called the original image. Voxel values in regions affected by artifacts are replaced with values from surrounding regions. Thus, a “prior” image is built. The prior image represents prior knowledge that can be used to guide ray-sum estimation within the metal trace. As in other sinogram in-painting methods, the measured raysums outside the traces are left unmodified. The corrected projections are reconstructed to provide the artifact-reduced image.