1. Department of Radiology, California Northstate University College of Medicine, Elk Grove, CA.
2. Department of Radiology, University of California, Davis, 4860 Y St, Ste 3100, Sacramento, CA 95864.
3. Department of Public Health Sciences, Division of Biostatistics, University of California, Davis, Davis, CA.
4. Department of Urology, University of California, Davis, Sacramento, CA.