1. Department of Otorhinolaryngology-Head and Neck Surgery, Hallym University Chuncheon Sacred Heart Hospital, Chuncheon, Korea.
2. Institute of New Frontier Research, Hallym University College of Medicine, Chuncheon, Korea.
3. Department of Otorhinolaryngology, Armed Forces Capital Hospital, Seongnam, Korea.
4. Department of Otorhinolaryngology-Head and Neck Surgery, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul, Korea.