1. Department of Neurosurgery, Pituitary & Endoscopic Surgery Center, Teikyo University School of Medicine
2. Department of Neurological Surgery, Nippon Medical School
3. Department of Neurological Surgery, the Ohio State University
4. Department of Otolaryngology/Head & Neck Surgery, the Ohio State University
5. Department of Neurosurgery, Lariboisière Hospital, Paris VII-Diderot University
6. Japan Labor Health and Safety Organization, Tokyo Rosai Hospital