[1] Seoul Natl Univ, Dept Urol, Bundang Hosp, Seongnam 13620, South Korea
[2] Chonnam Natl Univ Hosp, Dept Urol, Gwangju 61469, South Korea
[3] Kyungpook Natl Univ, Sch Med, Med Ctr, Daegu 41404, South Korea
[4] Konkuk Univ, Dept Urol, Med Ctr, Seoul 05080, South Korea
[5] Wonkwang Univ Hosp, Dept Urol, Iksan 54538, South Korea
[6] Daegu Catholic Univ, Dept Urol, Med Ctr, Daegu 41911, South Korea
[7] Ulsan Univ, Gangneung Asan Hosp, Dept Urol, Kangnung 25440, South Korea
[8] Chungbuk Natl Univ Hosp, Dept Urol, Cheongju 28644, South Korea
[9] Soonchunhyang Univ Hosp, Dept Urol, Cheonan 31151, South Korea
[10] Hallym Univ, Dept Urol, Sacred Heart Hosp, Anyang 14068, South Korea
[11] Kangbuk Samsung Hosp, Dept Urol, Seoul 03181, South Korea
[12] Seoul St Mary Hosp, Dept Urol, Seoul 06591, South Korea