The following generally relates to scaling irregularity maps based at least on one of a histogram bin width, an image noise or a contrast agent concentration. A method includes obtaining a non-scaled irregularity map generated based on local weighted histograms of voxel distributions about voxels of interest from volumetric image data of a subject or object. The local weighted histograms include a plurality of bins having a predetermined bin width. The local weights are determined based on a predetermined cluster length. The method further includes scaling the non-scaled irregularity map, generating a scaled irregularity map. The non-scaled irregularity map is scaled based at least on the histogram bin width.