1. Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
2. University of New England College of Osteopathic Medicine, Biddeford, ME, USA
3. Department of Neurology, University of Washington, Seattle, USA
4. Department of Neurology, Beth Israel Deaconess, Harvard Medical School, Boston, USA
5. Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
6. Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, USA