1. Department of Anesthesia and Perioperative Care, The Center for Cerebrovascular Research, University of California, San Francisco, California, U.S.A.
2. Department of Neurosurgery, Hua-Shan Hospital, Shanghai Medical School, Fudan University, Shanghai, China
3. Department of Surgery, The Center for Cerebrovascular Research, University of California, San Francisco, California, U.S.A.
4. Department of Neurological Surgery, The Center for Cerebrovascular Research, University of California, San Francisco, California, U.S.A.
5. Department of Neurology, The Center for Cerebrovascular Research, University of California, San Francisco, California, U.S.A.