1. Department of Neurology, MS Center, VU University Medical Center, Amsterdam, The Netherlands,
2. Department of Clinical Epidemiology and Biostatistics, MS-MRI Center, VU University Medical Center, Amsterdam, The Netherlands
3. Department of Radiology, MS-MRI Center, VU University Medical Center, Amsterdam, The Netherlands
4. Department of Neurology, MS Center, VU University Medical Center, Amsterdam, The Netherlands
5. Department of Neurology, MS Center, VU University Medical Center, Amsterdam, The Netherlands, Department of Clinical Epidemiology and Biostatistics, MS-MRI Center, VU University Medical Center, Amsterdam, The Netherlands