1. Department of Neurosurgery, The Affiliated Hospital of Guizhou Medical University, Guiyang, P.R. China
2. Department of Neurosurgery, The Jinyang Hospital Affiliated to Guizhou Medical University, Guiyang, P.R. China
3. Department of Pathology, The Affiliated Hospital of Guizhou Medical University, Guiyang, P.R. China
4. Department of Neurosurgery, Guizhou Provincial People’s Hospital, Guiyang, P.R. China