Nathan R Webb1, M K Jesse2. 1. Department of Radiology, University of Colorado School of Medicine, Mail Stop 8200, AO1, Rm 2414, 12631 East 17th Avenue, Aurora, CO, 80045, USA. nathan.webb@ucdenver.edu. 2. Department of Radiology, University of Colorado School of Medicine, Mail Stop 8200, AO1, Rm 2414, 12631 East 17th Avenue, Aurora, CO, 80045, USA.