1. Department of Otorhinolaryngology-Head and Neck Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea.
2. Department of Otorhinolaryngology-Head and Neck Surgery, Hallym University College of Medicine, Chunchen, Korea.
3. Department of Otorhinolaryngology-Head and Neck Surgery, Hallym University Kangnam Sacred Heart Hospital, Seoul, Korea.