Xiang Yang1, Jun Le1, Xin Hu1, Yuekang Zhang1, Jiagang Liu2. 1. From the Department of Neurosurgery (X.Y., X.H., Y.Z., J. Liu), West China Hospital, Sichuan University Chengdu; and Department of Neurosurgery (J. Le), Yingtan People's Hospital of Jiangxi, P.R. China. 2. From the Department of Neurosurgery (X.Y., X.H., Y.Z., J. Liu), West China Hospital, Sichuan University Chengdu; and Department of Neurosurgery (J. Le), Yingtan People's Hospital of Jiangxi, P.R. China. yangxiangcool2017@163.com.