1. From the NIHR King's Clinical Research Facility (P.J.G.), King's College London, United Kingdom; Department of Neurology (P.J.G.), University of California, Los Angeles; Key-Whitman Eye Center (D.I.F.), Dallas, TX; Department of Neurology (D.H.-L.), West German Headache and Vertigo Center Essen, University of Essen, Germany; Department of Neurology (G.D.), Hospices Civils de Lyon, Lyon Neuroscience Research Center, France; BIDMC Comprehensive Headache Center (S.A.), Beth Israel Deaconess Medical...