1. Department of Neurosurgery, Qilu Hospital of Shandong University, Jinan 250012, Shandong Province, P.R. China
2. Department of Neurosurgery, Liaocheng People’s Hospital, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Liaocheng 252000, Shandong Province, P.R. China
3. Department of Pediatrics, Liaocheng People’s Hospital, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Liaocheng 252000, Shandong Province, P.R. China
4. Department of Neurosurgery, Binzhou Medical University Hospital, Binzhou Medical University, Binzhou 256603, Shandong Province, P.R. China