1. Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland.
2. Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland.
3. Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland.
4. Department of Rehabilitation Services, University of Maryland School of Medicine, Baltimore, Maryland.
5. Department of Aeromedical Research, U.S. Air Force School of Aerospace Medicine, Research Initiatives, US Air Force c-STARS Baltimore, Baltimore, Maryland.
6. R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland.