1. Department of Urology, Tottori Prefectural Central Hospital, Tottori 680-0901, Japan
2. Department of Radiology, Tottori Prefectural Central Hospital, Tottori 680-0901, Japan
3. Division of Urology, Department of Surgery, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan