1. A computer-implemented method for determining an attribute of a region of interest represented by a plurality of voxels, the method comprising: identifying a seed voxel that corresponds to a location completely within the region of interest; performing region-growth to identify a set of voxels, including voxels that correspond to locations completely within the region of interest and voxels that correspond to locations that are partially within the region of interest; and calculating the attribute of the region of interest, wherein the calculation includes applying a weighting function to the corresponding attribute of voxels of the set of voxels, wherein the corresponding attribute of the voxels of the set of voxels are weighted according to signal intensity.