Jinjin Liu1, Yunjun Yang2, Bing Zhao3. 1. Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China. 2. Department of Radiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China. yyjunjim@163.com. 3. Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200000, China. drzhaobing@yahoo.com.