1. Department of Radiology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA
2. Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110, USA
3. Departments of Neuroscience, Washington University School of Medicine, Saint Louis, MO 63110, USA
4. Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63110, USA
5. Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA
6. Physical Therapy and Occupational Therapy, Washington University School of Medicine, Saint Louis, MO, 63110, USA