U. Fischer, J. Kaesmacher, V.M. Pereira, R. Chapot, A.H. Siddiqui, M.T. Froehler, C. Cognard, A.J. Furlan, J.L. Saver, J. GrallaDepartment of Neurology, Department of Diagnostic and Interventional Neuroradiology, Inselspital, University Hospital Bern, Switzerland; University of Bern, Switzerland; Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technical University Munich, Germany; Division of Neuroradiology, Department of Medical Imaging and Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University Health Network, Ontario, Canada; Department of Radiology and Neuroradiology, Alfried Krupp Krankenhaus Essen, Germany; Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York; Vanderbilt University Medical Center, Nashville, TN; Department of Diagnostic and Therapeutic Neuroradiology, University Hospital of Toulouse, France; University Hospitals Case Medical Center, Neurological Institute, Case Western Reserve University, Cleveland, OH; UCLA Comprehensive Stroke Center, Geffen School of Medicine at UCLA, University of California, Los Angeles.