1. Department of Neurology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
2. Department of Neurology, St Josef Hospital, Ruhr University Bochum, Bochum, Germany
3. Deutschen Klinik für Diagnostik Helios Klinik Wiesbaden, Wiesbaden, Germany
4. Department of Neurology, Clinic Osnabrück, Osnabrück, Germany