Affiliation: | 1.Department of Neurology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussel (UZ Brussel), Brussels, Belgium ;2.Department of Neurology, General Hospital Sint-Jan Bruges, Bruges, Belgium ;3.Department of Neurology, Ghent University Hospital, Ghent, Belgium ;4.Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany ;5.Headache Research Unit, Dept of Neurology-Citadelle Hospital, University of Liège, Liège, Belgium |