1. From the Department of Neurology (E.M.A., A.W.L., R.F.G., M.N.B., R.W.) and the Neuro-Ophthalmology Unit (C.S.C., N.R.M.), Wilmer Eye Institute, The Johns Hopkins Hospital, Baltimore, Md; and the Division of Interventional Neuroradiology, Department of Radiology (P.G., K.M.), The Johns Hopkins Hospital, Baltimore, Md.