1. College of Osteopathic Medicine, University of New England, Biddeford, ME 04005, USA
2. Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02115, USA
3. Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02115, USA
4. Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02115, USA
5. Northern Light Neurosurgery and Spine, Bangor, ME 04401, USA