1 From the New England Center for Stroke Research, Department of Radiology, University of Massachusetts Medical School, Worcester (M.J.G., G.J.U., M.M., A.S.P.).
2 Department of Neurosurgery, Advocate Health, Chicago, IL (D.K.L.).
3 Department of Neurosurgery, Stony Brook University, NY (D.F.).
4 Harrington Heart and Vascular Center, University Hospitals Cleveland Medical Center, OH (H.G.B.).
5 Department of Neurosurgery, Kaiser Permanente Fontana Medical Center, CA (C.W.L.).