[1] Chung Ang Univ, Chung Ang Univ Hosp, Coll Med, Dept Radiol, Seoul, South Korea
[2] Sungkyunkwan Univ, Sch Med, Kangbuk Samsung Hosp, Dept Radiol, 29 Saemunan Ro, Seoul 03181, South Korea
[3] Univ Ulsan, Coll Med, GangNeung Asan Hosp, Dept Radiol, Kangnung, South Korea
[4] Human Med Imaging & Intervent Ctr, Dept Radiol, Seoul, South Korea
[5] New Korea Hosp, Dept Radiol, Gimpo, South Korea
[6] Sungkyunkwan Univ, Sch Med, Kangbuk Samsung Hosp, Div Biostat,Dept R&D Management, Seoul, South Korea