1. Department of Endovascular Neurosurgery, Toranomon Hospital
2. Division for Stroke, Department of Neurosurgery, Faculty of Medicine, University of Tsukuba
3. Department of Neurosurgery, Graduate School of Medical Sciences, Kyushu University
4. Department of Neurosurgery, National Cerebral and Cardiovascular Center
5. Department of Neurosurgery, Kobe City Medical Center General Hospital
6. Department of Neurosurgery, Faculty of Medicine, University of Tsukuba