caa a22 4500 445809728 CHVBK 20181103083412.0 cr unu---uuuuu 170323e20110401xx s 000 0 eng 10.1007/s00415-010-5806-y doi (NATIONALLICENCE)springer-10.1007/s00415-010-5806-y Effect of 4-aminopyridine on gravity dependence and neural integrator function in patients with idiopathic downbeat nystagmus [Elektronische Daten] [T. Sander, A. Sprenger, S. Marti, T. Naumann, D. Straumann, C. Helmchen] Downbeat nystagmus (DBN) is a frequent sign in patients with cerebellar degeneration. It consists of an upward drift of the eye that does not depend on vertical head position (spontaneous drift, SD), a gravity-dependent component (GD), and a gaze-evoked drift reflecting gaze-holding impairment (deficient neural integrator function). The potassium-channel blocker 4-aminopyridine (4-AP) is reported to reduce DBN in patients with cerebellar atrophy but with little or no effect in patients with idiopathic DBN. We prospectively studied the effect of 4-AP on all three components in a large (n=24) group of the clinically frequent idiopathic DBN. DBN was reduced by 22-31% when the head was off the head erect position. In contrast, there was no effect on vertical gaze-evoked drift. This indicates the therapeutic efficacy of 4-AP not only in patients with cerebellar atrophy but also in idiopathic DBN patients. This beneficial effect, which might be missed when gravity-dependent head positions are not tested, was not related to an improvement of gaze-holding deficit. We suggest it may be related to the restored inhibition of the overacting otolith−ocular reflex. Springer-Verlag, 2010 Downbeat nystagmus nationallicence Aminopyridines nationallicence Cerebellum nationallicence Oscillopsia nationallicence Central eye movement disorder nationallicence DBN : Downbeat nystagmus nationallicence PC : Purkinje cells nationallicence VOR : Vestibulo-ocular reflex nationallicence AP : Aminopyridines nationallicence SD : Spontaneous vertical drift velocity on gaze straight ahead with the head erect nationallicence GD : Gravity-dependent component nationallicence SPV : Slow phase velocity nationallicence EPS : Eye position sensitivity nationallicence Sander T. Department of Neurology, University Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany aut Sprenger A. Department of Neurology, University Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany aut Marti S. University Hospital Zurich, Zurich, Switzerland aut Naumann T. Department of Neurology, University Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany aut Straumann D. University Hospital Zurich, Zurich, Switzerland aut Helmchen C. Department of Neurology, University Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany aut Journal of Neurology Springer-Verlag 258/4(2011-04-01), 618-622 0340-5354 258:4<618 2011 258 415 https://doi.org/10.1007/s00415-010-5806-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00415-010-5806-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sander T. Department of Neurology, University Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany aut NATIONALLICENCE 700 1- Sprenger A. Department of Neurology, University Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany aut NATIONALLICENCE 700 1- Marti S. University Hospital Zurich, Zurich, Switzerland aut NATIONALLICENCE 700 1- Naumann T. Department of Neurology, University Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany aut NATIONALLICENCE 700 1- Straumann D. University Hospital Zurich, Zurich, Switzerland aut NATIONALLICENCE 700 1- Helmchen C. Department of Neurology, University Luebeck, Ratzeburger Allee 160, 23538, Luebeck, Germany aut NATIONALLICENCE 773 0- Journal of Neurology Springer-Verlag 258/4(2011-04-01), 618-622 0340-5354 258:4<618 2011 258 415 Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 285499602 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer