1. Department of Neurosurgery, Chiba Hokuso Hospital, Nippon Medical School
2. Department of Internal Medicine, Chiba Hokuso Hospital, Nippon Medical School
3. Department of Internal Medicine, Nippon Medical School
4. Department of Radiology, Chiba Hokuso Hospital, Nippon Medical School
5. Department of Neurosurgery, Kushiro Rosai Hospital
6. Department of Neurosurgery, Nippon Medical School