1. Department of Neurosurgery, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China.
2. Department of Neurosurgery, Weifang People's Hospital, Weifang, Shandong, China.
3. Department of Neurosurgery, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, P.R. China.
4. Department of Neurosurgery, Binhai People's Hospital, Binhai, China.