1. From the Neurovascular Clinical Science Unit (M.M., C.A.D., O.C.S., A.M., N.H., D.C., D.H., E.B.W., G.H., L.K., J.D., P.J.K.), Mater University Hospital/University College Dublin, Ireland; Connolly Hospital (P.M.E.M.), Dublin, Ireland; Beaumont Hospital (A.M.), Dublin, Ireland; and Centre for Support and Training in Analysis and Research (G.C.-O.), University College Dublin, Ireland.