1. Department of Otolaryngology, Japanese Red Cross Wakayama Medical Center
2. Department of Otolaryngology, Head and Neck Surgery, Shizuoka Municipal Hospital
3. Department of Otolaryngology, Kobe City Medical Center General Hospital
4. Department of Otolaryngology, Head and Neck Surgery, Kokura Memorial Hospital
5. Department of Otolaryngology, Head and Neck Surgery, Kyoto University Graduate School of Medicine
6. Ikeda Ear, Nose and Throat Clinic