1. Department of Neurology Graduate School of Medicine Dentistry and Pharmaceutical Sciences Okayama University Okayama Japan
2. Department of Neurology Tsuyama Central Hospital Tsuyama Japan
3. Department of Neurosurgery Tsuyama Central Hospital Tsuyama Japan
4. Department of Gastrointestinal Surgery Tsuyama 1st Hospital Tsuyama Japan
5. Department of Internal Medicine Sato Memorial Hospital Katsuta gun Japan
6. Department of Internal Medicine Tajiri Hospital Mimasaka Japan
7. Department of Neurosurgery Kaneda Hospital Maniwa Japan
8. Department of Orthopedics Sayo Central Hospital Sayo‐gun Japan