[1] Seoul Natl Univ, Bundang Hosp, Dept Radiol, 82 Gumi 173beon Gil, Seongnam 13620, Gyeonggi, South Korea
[2] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Radiol, 86 Asanbyeongwon Gil, Seoul 05505, South Korea
[3] Univ Ulsan, Coll Med, Asan Med Ctr, Res Inst Radiol, 86 Asanbyeongwon Gil, Seoul 05505, South Korea
[4] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Pathol, 86 Asanbyeongwon Gil, Seoul 05505, South Korea
[5] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Otorhinolaryngol Head & Neck Surg, 86 Asanbyeongwon Gil, Seoul 05505, South Korea