1. Department of Neurology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
2. Department of Surgery, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
3. Integrated Services Group, Inc., Potomac, Maryland.
4. Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina.
5. Department of Neuroscience, Inova Fairfax Hospital, Fairfax, Virginia.