1. 1Neuroradiology Division, Department of Radiology, University of Virginia, Charlottesville, Virginia;
2. 2Department of Neurology, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China;
3. 3Department of Neurology, Center for Stroke Research Berlin, Charité–Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany; and
4. 4Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Switzerland