1. Department of Neurosurgery, Nippon Medical School Tama Nagayama Hospital
2. Department of Neurosurgery, Graduate School of Medicine, Nippon Medical School
3. Department of Neurosurgery, Kushiro Rosai Hospital
4. Department of Neurosurgery, Nippon Medical School Chiba Hokuso Hospital
5. Department of Neurosurgery, Nippon Medical School