目的:比较前庭眼反射(VOR)增益,头晕但VOR增益正常的患者与健康对照组之间的头部冲动期间的代偿扫视和头部和眼睛协调。
方法:视频头脉冲测试(vHIT;ICS脉冲,Otometrics,丹麦)对40名参与者(20名头晕患者;20名对照)进行了审查。VOR增益,扫视特征(发生频率,振幅,潜伏期)和头眼速度之间的时间差进行了比较。
结果:两组间VOR增益无显著差异。然而,头晕患者的扫视频率更高,头眼之间的时间差延长。扫视振幅没有观察到显著差异,也不是组之间的扫视延迟。
结论:本研究强调,在VOR增益正常的患者中观察到的扫视可以反映VOR增益正常的患者头晕的临床标志。我们建议这些扫视是由头部和眼睛速度之间的长时间延迟引起的,从而导致注视位置误差。
结论:结果支持先前的发现,表明在解释vHIT结果时,扫视和时间延迟的附加价值。这项研究进一步提出了时间延迟作为解释正常VOR增益的头晕患者扫视频率增加的可能机制。
OBJECTIVE: Compare the vestibulo-ocular reflex (VOR) gain, compensatory
saccades and head and eye coordination during head impulses between patients with dizziness but normal VOR gain and healthy controls.
METHODS: Video head impulses test (vHIT; ICS impulse, Otometrics, Denmark) was reviewed in 40 participants (20 patients with dizziness; 20 controls). VOR gain,
saccades characteristics (frequency of occurrence, amplitude, latency) and time difference between head and eye velocity was compared.
RESULTS: No significant difference between groups was observed for VOR gain. However, saccade frequency was greater and time difference between head and eye was prolonged in patients with dizziness. No significant difference was observed for saccade amplitude, nor for saccade latency between groups.
CONCLUSIONS: The present study highlights that
saccades observed in patients with normal VOR gain could reflect a clinical marker for dizziness in patients with normal VOR gain. We propose that theses
saccades are caused by a prolonged time delay between head and eye velocity leading to a gaze position error.
CONCLUSIONS: The results support previous findings suggesting additional value of
saccades and time delay when interpreting vHIT results. This study goes further by proposing time delay as a possible mechanism to explain increased saccade frequency in dizzy patients with normal VOR gain.