1. Department of Otorhinolaryngology–Head and Neck Surgery, Bundang Jesaeng General Hospital, Deajin Medical Center, Seongnam, Korea
2. Department of Otorhinolaryngology–Head and Neck Surgery, Pusan National University College of Medicine, Pusan, Korea
3. Department of Otorhinolaryngology–Head and Neck Surgery, Seoul National University College of Medicine, Seoul, Korea
4. Department of Otorhinolaryngology–Head and Neck Surgery, Hallym University College of Medicine, Chuncheon, Korea
5. Department of Otorhinolaryngology–Head and Neck Surgery, Dongguk University College of Medicine, Seoul, Korea