Optimising electrical vestibular stimulation (EVS) for assessing vestibular function

IF 2 Q3 NEUROSCIENCES

Clinical Neurophysiology Practice Pub Date : 2025-01-01 DOI:10.1016/j.cnp.2025.08.006

Raphael Hamel , Peter Gaskell , Sophie Prosser , Darren Whelan , Richard Irving , Raymond Francis Reynolds

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引用次数: 0

Abstract

Objective

Electrical vestibular stimulation (EVS) exhibits similar diagnostic performance to caloric irrigation for assessing interaural vestibular asymmetry. To optimise EVS for clinical uses, we investigated the influence of EVS stimulus parameters upon absolute torsional eye response amplitude and asymmetry assessments.

Methods

In young healthy adults (n = 72), monoaural sinusoidal EVS was delivered to each mastoid process for 40 s whilst ocular torsion was assessed. Ambient lights, electrode montage, and stimulus frequency were systematically manipulated.

Results

Ambient lights (250 lx) attenuated torsional responses by 20 % compared to darkness. When the reference electrode was next to C7 (i.e., mastoid-C7 montage), responses to monoaural stimuli were 50 % those of binaural stimulation. Sinusoidal stimuli at 0.5 Hz evoked torsional responses 250 % larger than at 2 Hz but required 300 % more time to estimate asymmetry (12sec vs 4sec). Perceived discomfort was lower at 0.5 Hz than at 2 Hz. Pooled results (n = 53) suggest a normative asymmetry range of 0 ± 25 % for assessing pathological asymmetry.

Conclusions

Darkness and lower stimulus frequencies optimise absolute torsional eye response amplitude. Higher stimulus frequencies accelerate asymmetry assessments. To activate a single vestibular end organ, a mastoid-C7 (or mastoid-acromioclavicular) montage should be used.

Significance

These results extend the clinical potential of EVS for assessing vestibular function.

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优化前庭电刺激（EVS）评估前庭功能

目的前庭电刺激（EVS）在评估耳间前庭不对称方面表现出与热灌相似的诊断性能。为了优化EVS的临床应用，我们研究了EVS刺激参数对绝对扭眼反应振幅和不对称性评估的影响。方法对72例年轻健康成人进行单耳正弦EVS注射，观察眼扭转情况，观察其对乳突的影响。环境光、电极蒙太奇和刺激频率被系统地操纵。结果与黑暗相比，环境光（250 lx）可使扭转响应减弱20%。当参考电极靠近C7（即乳突-C7蒙太奇）时，对单耳刺激的反应是双耳刺激的50%。0.5 Hz的正弦刺激引起的扭转反应比2 Hz大250%，但需要多300%的时间来估计不对称性（12秒比4秒）。0.5 Hz时的感觉不适感低于2 Hz。合并结果（n = 53）表明，评估病理不对称性的标准不对称性范围为0±25%。结论黑暗和较低的刺激频率可优化绝对扭眼反应幅度。较高的刺激频率加速了非对称性评估。要激活单个前庭末端器官，应使用乳突- c7（或乳突-肩锁）蒙太奇。意义这些结果拓展了EVS在评估前庭功能方面的临床应用潜力。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Clinical Neurophysiology Practice NEUROSCIENCES-

CiteScore

3.90

自引率

0.00%

发文量

审稿时长

71 days

期刊介绍： Clinical Neurophysiology Practice (CNP) is a new Open Access journal that focuses on clinical practice issues in clinical neurophysiology including relevant new research, case reports or clinical series, normal values and didactic reviews. It is an official journal of the International Federation of Clinical Neurophysiology and complements Clinical Neurophysiology which focuses on innovative research in the specialty. It has a role in supporting established clinical practice, and an educational role for trainees, technicians and practitioners.