1. Department of Otorhinolaryngology – Head and Neck Surgery, Myongji Hospital, Hanyang University College of Medicine, Goyang, Korea
2. Department of Otorhinolaryngology – Head and Neck Surgery, School of Medicine, Kyung Hee University, Seoul, Korea
3. St. Vincent’s Hospital, The Catholic University of Korea, Suwon, Korea
4. Kyung Hee University Medical Center, Medical Science Research Institute, Seoul, Republic of Korea