[1] Sungkyunkwan Univ, Dept Otorhinolaryngol Head & Neck Surg, Samsung Med Ctr, Sch Med, Seoul, South Korea
[2] Dankook Univ Hosp, Dept Otorhinolaryngol Head & Neck Surg, Cheonan, South Korea
[3] Gyeongsang Natl Univ Hosp, Dept Otorhinolaryngol Head & Neck Surg, Jinju, South Korea
[4] Sungkyunkwan Univ, Dept Radiol, Samsung Med Ctr, Sch Med, Seoul, South Korea