1. The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, China
2. Department of Neurosurgery, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
3. The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou 510006, China
4. Department of Neurosurgery, Faculty of Medicine, Hokkaido University, Sapporo 060-8638, Japan