1. From the Departments of Neurology (M.M., M.B.) and Pediatrics (A.K.), Massachusetts General Hospital, the Departments of Neurology (M.M., M.B.), Radiology (A.F.J.), and Pediatrics (A.K.), Harvard Medical School, and the Department of Radiology, Massachusetts Eye and Ear Infirmary (A.F.J.) — all in Boston.