1. Harborview Injury Prevention Research Center, Harborview Medical Center, University of Washington, Seattle, Washington.
2. Department of Neurological Surgery, University of Washington, and Seattle Children's Hospital, Seattle, Washington.
3. Radiology Clinical Research Imaging Core, Center for Clinical and Translational Research, Seattle Children's Hospital, Seattle, Washington.
4. Department of Radiology, Seattle Children's Hospital, University of Washington, and Seattle Children's Hospital, Seattle, Washington.
5. Department of Anesthesia & Pain Medicine, Harborview Medical Center, University of Washington, Seattle, Washington.
6. Department of Pediatrics, Seattle Children's Hospital, University of Washington, and Seattle Children's Hospital, Seattle, Washington.