Sprenger Andreas, Zils Elisabeth, Rambold Holger, Sander Thurid, Helmchen Christoph
Department of Neurology, University of Lübeck, Germany.
Ann N Y Acad Sci. 2005 Apr;1039:395-403. doi: 10.1196/annals.1325.037.
Downbeat nystagmus (DBN) is a common, usually persistent ocular motor sign in vestibulocerebellar midline lesions. Postural imbalance in DBN may increase on lateral gaze when downbeat nystagmus increases. 3,4-Diaminopyridine (3,4-DAP) has been shown to suppress the slow-phase velocity component of downbeat nystagmus and its gravity-dependent component with concomitant improvement of oscillopsia. Because the pharmacological effect is thought to be caused by improvement of the vestibulocerebellar Purkinje cell activity, the effect of 3,4-DAP on the postural control of patients with downbeat nystagmus syndrome was examined. Eye movements were recorded with the video-based Eyelink II system. Postural sway and pathway were assessed by posturography in lateral gaze in the light and on eye closure. Two out of four patients showed an improvement of the area of postural sway by 57% of control (baseline) on eye closure. In contrast, downbeat nystagmus in gaze straight ahead and on lateral gaze did not benefit in these two patients, implying a specific influence of 3,4-DAP on the vestibulocerebellar control of posture. It was concluded that 3,4-DAP may particularly influence the postural performance in patients with downbeat nystagmus.
下跳性眼球震颤（DBN）是前庭小脑中线病变中常见的、通常持续存在的眼球运动体征。当下跳性眼球震颤增强时，DBN患者在侧视时的姿势失衡可能会加重。3,4-二氨基吡啶（3,4-DAP）已被证明可抑制下跳性眼球震颤的慢相速度成分及其重力依赖性成分，并同时改善视振荡。由于认为这种药理作用是由前庭小脑浦肯野细胞活性的改善引起的，因此研究了3,4-DAP对下跳性眼球震颤综合征患者姿势控制的影响。使用基于视频的Eyelink II系统记录眼动。通过姿势描记法评估在明亮环境下和闭眼时侧视时的姿势摆动和路径。四名患者中有两名在闭眼时姿势摆动面积改善了对照（基线）的57%。相比之下，这两名患者在直视和侧视时的下跳性眼球震颤并无改善，这意味着3,4-DAP对姿势的前庭小脑控制有特定影响。得出的结论是，3,4-DAP可能对下跳性眼球震颤患者的姿势表现有特别影响。
