1. From the Departments of Radiology and Urology, Tulane University Health Sciences Center, New Orleans, Louisiana, Departments of Radiology and Urology, State University of New York, Downstate Medical School, Brooklyn, New York, Departments of Radiology and Urology, UMDNJ, New Jersey Medical School, Newark, New Jersey, Departments of Radiology and Urology, AKH University of Vienna Medical Faculty, Vienna, Austria, and Department of Urology, Temple University School of Medicine, Philadelphia, Pennsylvania