[1] Univ Dusseldorf, Neurol Klin, Dusseldorf, Germany
[2] Univ Dusseldorf, Neurol Klin, Zentrum Neurol & Neuropsychiat, LVR Klinikum Dusseldorf, Dusseldorf, Germany
[3] Harvard Univ, Brigham & Womens Hosp, Ctr Neurol Dis, Sch Med, Boston, MA 02115 USA