Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China. yuanfang@fmmu.edu.cn. Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China. fyangx@fmmu.edu.cn. Department of Neurology, Tangdu Hospital, Fourth Military Medical University, Xi'an, 710038, China. Department of Neurology, Xi'an Gaoxing Hospital, Xi'an, 710075, China. Department of Neurology, Yulin No.1 Hospital, Yulin, 719000, China. Department of Neurology, Yan'an University Affiliated Hospital, Yanan, 716000, China. Department of Neurology, Xi'an Central Hospital, Xi'an, 710003, China. Department of Neurology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China. Department of Neurology, Tongchuan People's Hospital, Tongchuan, 727000, China. Department of Neurology, Weinan Central Hospital, Weinan, 714000, China. Department of Neurology, Tongchuan Mining Bureau Hospital, Tongchuan, 727000, China. Department of Neurology, The First Affiliated Hospital of Xi'an Medical University, Xi'an, 710077, China. Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, China. jiangwen@fmmu.edu.cn. The Shaanxi Cerebrovascular Disease Clinical Research Center, Xi'an, 710032, China. jiangwen@fmmu.edu.cn.