1. Department of Neurosurgery; Kyorin University School of Medicine; Tokyo Japan
2. Department of Neurosurgery; Fuji Brain Institute and Hospital; Shizuoka Japan
3. Department of Stroke and Cerebrovascular Medicine; Kyorin University School of Medicine; Tokyo Japan
4. The Center for Comprehensive Care and Research on Memory Disorders; National Center for Geriatrics and Gerontology; Aichi Japan