1. A method for automatically identifying one or more structural regions in a volume imaging slice, comprising: acquiring a volume imaging slice; labeling two or more regions within the volume imaging slice to form a labeled slice; flood-filling the interior of each region of the labeled slice to form a flood-filled slice; computing a distance map of each region of the flood-filled slice; computing one or more statistics for each region using at least one of the volume imaging slice, the distance map, and the flood-filled slice; and applying a rule-based classifier to the one or more statistics for each region to classify each region as one of bone, vessel, and indeterminate.