1. Virginia Tech Carilion School of Medicine, Roanoke, Virginia, USA.
2. Department of Neurosurgery, Carilion Clinic, Roanoke, Virginia, USA.
3. School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
4. Department of Internal Medicine, Carilion Clinic, Roanoke, Virginia, USA.
5. Department of Psychiatry and Behavioral Medicine, Carilion Clinic, Roanoke, Virginia, USA.