1. From the Department of Neurology (P.G.-P., V.P.-M., K.C., W.S.D.), Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Neurology (E.S.D.A.), Nationwide Children's Hospital, Columbus, OH; and Department of Neurology (V.P.-M., A.A.A.), Brigham Women's Hospital, Harvard Medical School, Boston, MA.