1 Department of Neurology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany (Gruchot J, Reiche L, Küry P).
2 Department of Neurology, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland (Chan A, Hoepner R, Küry P).