1. From the Department of Neurology (J.G.S.L.), SUNY Upstate Medical University, Syracuse, NY; the Department of Neurology (S.H.-Y.C.), Brigham and Women’s Hospital, Harvard Medical School, Boston, Mass; the Departments of Neurology and Interventional Neuroradiology (R.G.N.), Neurosurgery (B.S.C., C.S.O.), and Neurology (A.B.S., G.A.R.), Massachusetts General Hospital, Harvard Medical School, Boston, Mass.