1. From the Stroke Research Group (L.C.J., J.E., R.L.F., M.M.B.), UCL Institute of Neurology, University College London; the Department of Neurology, the Adelaide and Meath Hospital, Dublin (D.J.H.M.); the National Children’s Hospital, Trinity College Dublin, Ireland (D.J.H.M.); and the Department of Neuroradiology (A.C.), St. George’s Hospital, London, England.