1. Neurovascular Research Laboratory, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, MA, USA
2. Emergency Headache Center, Lariboisiere Hospital, Assistance Publique-Hopitaux de Paris, France
3. DHU NeuroVasc, France
4. Inserm Research Center for Epidemiology and Biostatistics (U897), Team Neuroepidemiology, France
5. University of Bordeaux, College of Health Sciences, France
6. Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, MA, USA
7. Stroke Service and Neuroscience Intensive Care Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, MA, USA