1. From Department of Clinical Neurosciences and Radiology (B.K.M., T.T.S., M.E., N.R.K., A.M.D, M.D.H., M.G.) andDepartment of Community Health Sciences (B.K.M., Y.Z., A.M.D.,M.D.H., M.G.), Cumming School of Medicine, University of Calgary, Canada; Departments of Radiology (J.L.R.) and Medicine (A.S.), University of Alberta, Edmonton, Canada; Departments of Neuroradiology (J.T.) andGeriatric and Stroke Medicine(D.W.), Beaumont Hospital and the Royal College of Surgeons in Ireland, Dublin; Departments...