1. From the Department of Neurology and Neurological Surgery (Neurological Surgery)(D.J.F., R.L.G., K.M.R., M.R.C., R.G.D.), Interventional Neuroradiology Service (C.J.M., D.T.C., C.P.D.), and Mallinckrodt Institute of Radiology (C.J.M., D.T.C., R.L.G., K.M.R., R.G.D., C.P.D.), Washington University School of Medicine, St. Louis, Mo.