A method includes reconstructing measured projection data using an iterative statistical reconstruction algorithm that reduces image artifact caused by differences in variances in projections of the measured projection data used to update a voxel of the image for one or more voxels of the image. A reconstructor includes a processor that reconstructs measured projection data using an iterative statistical reconstruction algorithm that reduces or mitigates image artifact caused by differences in variances in projections used to update a voxel of the image for one or more voxels of the image. A computer readable storage medium encoded with computer executable instructions, which, when executed by a processor of a computer, cause the processor to: reduce image artifact caused by differences in variances in projections used to update a voxel of an image for one or more voxels of the image using an iterative statistical reconstruction algorithm.