1. From the Department of Neurology (S.H.-Y.C.), Brigham and Women’s Hospital, Harvard Medical School, and the Departments of Neurology (E.E.S., R.G.N., J.R.S., G.A.R., C.A.), Radiology (R.G.N., J.R.S., C.A.), and Neurosurgery (C.S.O.), Massachusetts General Hospital, Harvard Medical School, Charlestown, Mass; and the Department of Neurology and Neurosurgery (N.B.), Columbia University College of Physicians and Surgeons, New York.