1. Emergency Department, Xuan Wu Hospital, Capital Medical University, Beijing, China
2. Institute of Hypoxia Medicine, Xuan Wu Hospital, Capital Medical University, Beijing, China
3. Department of Neurosurgery, Wayne State University School of Medicine, Detroit, USA
4. Vascular Ultrasound Division, Xuan Wu Hospital, Capital Medical University, Beijing, China
5. Department of Neurosurgery and Brain Repair, University of South Florida, Morsani College of Medicine, Tampa, FL, USA
6. Department of Neurosurgery, Xuan Wu Hospital, Capital Medical University, Beijing, China