1. Department of Otolaryngology-Head and Neck Surgery, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea.
2. Department of Otolaryngology-Head and Neck Surgery, Maryknoll Medical Center, Busan, Korea.
3. Department of Otolaryngology-Head and Neck Surgery, Dong-A University College of Medicine, Busan, Korea.
4. Department of Anatomy and Tumor Immunology, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea.
5. Department of Otolaryngology-Head and Neck Surgery, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea.