1. Department of Anesthesiology and Pain Management; Maastricht University Medical Center; PO Box 5800 6202 AZ Maastricht The Netherlands
2. Department of Neurology; Maastricht University Medical Center; PO Box 5800 6202 AZ Maastricht The Netherlands
3. Department of Neurology; Spaarne Hospital; Spaarnepoort 1 2134 TM Hoofddorp The Netherlands