1. From the Calgary Stroke Program (M.D.H., M.E., A.M.B.), Department of Clinical Neurosciences, University of Calgary, Foothills Hospital, Calgary, Alberta, Canada; the Department of Radiology (H.A.W.), University of Wisconsin, Madison; Yale University Medical School (F.A.), New Haven, Conn; the Cleveland Clinic Neurovascular Center (A.F.), Cleveland, Ohio; Department of Radiology, University of California at San Francisco Medical School (R.T.H., W.P.D., N.J.F.), San Francisco, Calif; the University...