1. Department of Otolaryngology-Head and Neck Surgery, Nara Medical University, 840 Shijo-Cho, Kashihara 634-8521, Nara, Japan
2. Graduate School of Engineering Science, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan
3. MBT (Medicine-Based Town) Institute, Nara Medical University, 840 Shijo-Cho, Kashihara 634-8521, Nara, Japan