New tests of vestibular function.
New tests of vestibular function.
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前庭功能的新测试。
DOI：
10.1111/j.1749-6632.2001.tb03764.x
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发表时间：
2001
影响因子：
5.2
通讯作者：
Wiest,G
中科院分区：
文献类型：
--
作者：
Demer,JL;Crane,BT;Tian,JR;Wiest,G
摘要：前庭眼球反射(VOR)是眼球短潜伏期运动的唯一驱动力，在外加、突然、高头加速时稳定视网膜。新的策略可以利用这一独特的VOR特征，在与患者日常生活相关的条件下进行研究，并排除混淆的非前庭机制的影响。测试在≤2800°/s2下以中心和偏心轴提供的随机全身旋转瞬变期间的偏航前庭眼球反射(VOR)，可以测量人类耳道和耳石VORS的增益和毫秒潜伏期。在急性单侧去传入的重复测量中，耳道和耳石的VORS顺序恢复到对侧旋转，但严重和永久性地丧失到自己的旋转。双侧热量反应丧失的患者表现为由于瞬时旋转而严重丧失双侧VORS，这表明在中等频率的正弦旋转中，他们的VORS的明显保留可能是由于体感输入。由于视网膜图像运动会降低视力，只有在方向和时间不可预测的高加速度头部运动中出现视型时，施加头部对身体或全身瞬时运动时测量的动态视敏度(DVA)才能与VOR表现密切相关。前庭疾病患者坚持不懈地使用预测和传出复制，以在可预测或低加速的头部运动期间实现良好的DVA。对瞬时横向加速度的线性VOR强烈依赖于观察距离。这种耳石VOR的潜伏期比耳道VOR稍长，也更加多变。与管VOR不同，耳石VOR在单侧去传入时不会形成强烈的方向不对称。双侧前庭病变时双侧耳石VOR减弱，小脑变性时耳石VOR丧失靶距依赖性。
Abstract:The vestibulo‐ocular reflex (VOR) is the only drive for short‐latency eye movements stabilizing the retina during externally imposed, sudden, high‐head accelerations. New strategies can exploit this unique VOR feature to study it under conditions relevant to the daily lives of patients, and to exclude the contributions from confounding nonvestibular mechanisms. Testing of the yaw vestibulo‐ocular reflex (VOR) during random, whole‐body rotational transients at ≤2800°/s2delivered about centered and eccentric axes enables measurement of gains and millisecond latencies of the canal and otolith VORs in humans. Repeated measurements in acute unilateral deafferentation show sequential recovery of canal and otolith VORs to contralesional rotation, but severe and permanent deficits to ipsilesional rotation. Patients with bilateral loss of caloric responses show severe bilateral loss of VORs to transient rotation, suggesting that the apparent preservation of their VORs during sinusoidal rotations at moderate frequencies may be due instead to somatosensory inputs.Since visual acuity is degraded by retinal image motion, dynamic visual acuity (DVA) measured during imposed head‐on‐body or whole‐body transient motion can correlate closely with VOR performance only if optotypes are presented during directionally and temporally unpredictable, high‐acceleration head motion. Prediction and efference copy are relentlessly employed by vestibulopathic patients to enable good DVA during predictable or low‐acceleration head motion. The linear VOR to transient lateral acceleration is strongly dependent upon viewing distance. The latency of this otolith VOR is slightly longer and more variable than the canal VOR. Unlike the canal VOR, the otolith VOR does not develop a strong directional asymmetry in unilateral deafferentation. The otolith VOR is bilaterally attenuated in bilateral vestibulopathy, and loses target distance dependence in cerebellar degeneration.