1. Department of Otorhinolaryngology-Head and Neck Surgery; Korea University College of Medicine; Seoul Korea
2. Department of Otolaryngology - Head and Neck Surgery; Korea Cancer Center Hospital; Seoul Korea
3. Department of Otorhinolaryngology - Head and Neck Surgery; Seoul National University Hospital; Seoul Korea
4. Department of Otorhinolaryngology - Head and Neck Surgery; Seoul National University Bundang Hospital; Seoul Korea
5. Department of Otorhinolaryngology - Head and Neck Surgery; Sungkyunkwan University School of Medicine; Gyeonggi-do Korea
6. Department of Otorhinolaryngology - Head and Neck Surgery; Hallym University College of Medicine; Gangwon-do Korea
7. Department of Otorhinolaryngology - Head and Neck Surgery; Dankook University College of Medicine; Chungnam Korea
8. Department of Otorhinolaryngology - Head and Neck Surgery; Ulsan University College of Medicine; Seoul Korea
9. Department of Otorhinolaryngology-Head and Neck Surgery; Chungnam National University College of Medicine; Daejeon 305-764 Korea
10. Department of Otorhinolaryngology - Head and Neck Surgery; Pusan National University School of Medicine and Biomedical Research Institute; Busan Korea