1. Department of Neurosurgery, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
2. Department of Operation, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
3. Department of Training, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China