1. Department of Anesthesia and Perioperative Care, and Center for Cerebrovascular Research, University of California, San Francisco, San Francisco, California
2. Department of Neurological Surgery, and Center for Cerebrovascular Research, University of California, San Francisco, San Francisco, California
3. Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina
4. Department of Neurological Surgery, University of California, San Francisco, San Francisco, California
5. Department of Genetics, Duke University Medical Center, Durham, North Carolina
6. Departments of Anesthesia and Perioperative Care, Neurological Surgery, Neurology, and Center for Cerebrovascular Research, University of California, San Francisco, San Francisco, California