1. Department of Neurosurgery Yamaguchi University Graduate School of Medicine Yamaguchi Japan
2. Department of Biostatistics Yamaguchi University Graduate School of Medicine Yamaguchi Japan
3. Department of Neurosurgery Kobe City Medical Center General Hospital Kobe Japan
4. Department of Stroke Neurology National Hospital Organization Osaka National Hospital Osaka Japan
5. Department of Cerebrovascular Medicine National Cerebral and Cardiovascular Center Suita Japan
6. Division of Stroke Prevention and Treatment Department of Neurosurgery Faculty of Medicine University of Tsukuba Ibaraki Japan
7. Division of Development and Discovery of Interventional Therapy Tohoku University Hospital Sendai Japan
8. Department of Neurology Graduate School of Medicine Nippon Medical School Tokyo Japan
9. Department of Diagnostic Radiology Kobe City Medical Center General Hospital Kobe Japan
10. Department of Neurosurgery Hyogo College of Medicine Nishinomiya Japan
11. Department of Clinical Epidemiology Hyogo College of Medicine Nishinomiya Japan