1. Division of Otolaryngology, Tohoku Medical and Pharmaceutical University Hospital
2. Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine
3. Division of Medical Biochemistry, Department of Biomolecular Sciences, Saga Medical School
4. Technical Services Division, Tohoku Medical and Pharmaceutical University
5. Division of Pathology, Tohoku Medical and Pharmaceutical University