1. Department of Urology, Bucheon St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
2. Department of Urology, Perfect Urology Clinic, Seoul, Korea
3. Department of Urology, Uijeongbu St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
4. Department of Urology, St. Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea