1 1Department of Neurosurgery, University of Cincinnati, Cincinnati, Ohio.
2 2Division of Neuroimaging and Intervention, and New England Center for Stroke Research, Department of Radiology, University of Massachusetts, Worcester, Massachusetts.
3 3Department of Neurosurgery, Duke University, Durham, North Carolina; and.
4 4Department of Neurosurgery, Kuopio University, Kuopio, Finland.