1. Department of Otorhinolaryngology, Seoul National University College of Medicine, Boramae Medical Center, Seoul, Korea
2. Department of Otorhinolaryngology, Kangwon National University College of Medicine, Kangwon National University Hospital, Chuncheon, Korea
3. Department of Allergy and Clinical Immunology, Kangwon National University College of Medicine, Kangwon National University Hospital, Chuncheon, Korea