1. Department of Neurology, Kobe City Medical Center General Hospital, Kobe, Japan;
2. Department of Neurosurgery, Hyogo Medical University, Nishinomiya, Japan;
3. Department of Neurosurgery, Kobe City Medical Center General Hospital, Kobe, Japan;
4. Division of Stroke Prevention and Treatment, University of Tsukuba, Tsukuba, Japan;
5. Department of Neurology, Institute of Medicine, University of Tsukuba, Tsukuba, Japan;
6. Department of Neurosurgery, Juntendo University, Tokyo, Japan;
7. Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Japan;
8. Department of Neurosurgery, University of Tsukuba, Tsukuba, Japan;
9. Department of Neurosurgery, Kyoto University, Kyoto, Japan;
10. Department of Neurosurgery, Kindai University, Osaka-Sayama, Japan;
11. Department of Neurosurgery, Seijinkai Shimizu Hospital, Kyoto, Japan;
12. Department of Neurovascular Research, Kobe City Medical Center General Hospital, Kobe, Japan