[1] Vrije Univ Brussel, Brussels, Belgium
[2] Natl MS Ctr Melsbroek, Melsbroek, Belgium
[3] Katholieke Univ Leuven, Leuven, Belgium
[4] Vrije Univ Brussel, Ctr Neurosci, Brussels, Belgium
[5] Univ Ziekenhuis Antwerpen, Dept Neurol, Antwerp, Belgium
[6] Univ Ziekenhuis Jette, Dept Neurol, Jette, Belgium