1. Department of Neurosurgery, National Hospital Organization, Kyoto Medical Center
2. Department of Neurosurgery, Graduate School of Medicine, Kyoto University
3. Department of Neurosurgery, Kochi Medical School, Kochi University
4. Department of Neurosurgery, National Hospital Organization, Himeji Medical Center
5. Department of Neurosurgery, Kitano Hospital Medical Research Institute
6. Department of Neurosurgery, Sapporo Medical University