1. From the Departments of Neuroradiology (I.D., M.A., R.A., F.C., C.D., P.H.L., C.R., G.G., V.C.) and Neurology (N.G., L.C., I.M., C.A.), Hôpital Gui de Chauliac, Montpellier University Medical Center, 80 Avenue Augustin Fliche, Montpellier 34295, France; and Department of Clinical and Experimental Medicine, Section of Statistics, University of Pisa, Pisa, Italy (R.M.).