1. Department of Otorhinolaryngology–Head and Neck Surgery Soonchunhyang University College of Medicine, Seoul Hospital Seoul South Korea
2. Department of Otorhinolaryngology–Head and Neck Surgery Seoul National University College of Medicine, Seoul National University Boramae Medical Center Seoul South Korea
3. Department of Otorhinolaryngology–Head and Neck Surgery Pusan National University Hospital Pusan South Korea
4. Department of Otolaryngology–Head and Neck Surgery College of Medicine, The Catholic University of Korea Seoul South Korea
5. Department of Otolaryngology–Head and Neck Surgery Chonbuk National University College of Medicine Chonbuk South Korea
6. Department of Otorhinolaryngology–Head and Neck Surgery Hallym University College of Medicine Chuncheon South Korea
7. Department of Otorhinolaryngology–Head and Neck Surgery Seoul National University Bundang Hospital Seongnam South Korea