1. From the Department of Neurosciences, Medical University of South Carolina (T.N.T., M.I.C.), Charleston, SC; Brain and Spine Center, LLC (A.A.M.) Panama City, Fla; Department of Radiology, School of Medicine (S.T.) and Department of Biostatistics and Bioinformatics, School of Public Health (G.C., M.J.L.), Emory University (S.T., G.C., M.J.L.), Atlanta, Ga; and Departments of Neurosurgery and Radiology, Mayo Clinic (H.J.C.), Rochester, Minn.