1. Leiden University Medical Centre; Department of Neurology; Leiden The Netherlands
2. University of Bern; Department of Neurology; Bern Switzerland
3. Università Cattolica del Sacro Cuore; Department of Neurology; Rome Italy
4. University of Manchester, Manchester Academic Health Sciences Centre and Central Manchester University Hospitals NHS Foundation Trust; Manchester United Kingdom
5. University of Muenster; Department of Neurology; Muenster Germany
6. Ruhr-University Bochum; Department of Neurology; Bochum Germany