1. Department of Otoralyngology Head and Neck Surgery, Kagawa Prefectual Central Hospital
2. Department of Otoralyngology Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
3. Department of Otolaryngology, Okayama Saiseikai General Hospital
4. Division of Pathophysiology, Okayama University Graduate School of Health Sciences
5. Department of Patholosy, Kagawa Prefectual Central Hospital