1. Department of Head and Neck Surgery, Aichi Cancer Center Hospital, Aichi, Japan
2. Department of Otorhinolaryngology, Head and Neck Surgery, Nagoya City University Graduate School of Medical Sciences, Aichi, Japan
3. Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, Nara, Japan
4. Department of Otolaryngology, Toyohashi Municipal Hospital, Aichi, Japan
5. Department of Otorhinolaryngology, Head and Neck Surgery, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
6. Department of Otolaryngology, Kawasaki Medical School, Okayama, Japan
7. Department of Head and Neck Surgery and Otolaryngology, Asahi University Hospital, Gifu, Japan