1 Department of Otolaryngology-Head and Neck Surgery, Chungnam National University College of Medicine, Chungnam National University Sejong Hospital, Daejeon, South Korea.
2 Department of Otolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea.
3 Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul, South Korea.
4 Department of Otorhinolaryngology-Head and Neck Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
5 Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul, South Korea.