Affiliation: | 1. Faculty of Health Sciences, Hokkaido University, Kita 12, Nishi 5, Kita-ku, Sapporo, Hokkaido 060-0812, Japan;2. Department of Radiology, Hokkaido Memorial Hospital of Urology, 1-25, Kita 41, Higashi 1, Higashi-ku, Sapporo, Hokkaido 007-0841, Japan |