1. Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
2. Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
3. Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands2Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands