Vestibular Research Laboratory, School of Psychology, Faculty of Science, University of Sydney, Sydney, Australia.
Sydney Human Factors Research, School of Psychology, Faculty of Science, University of Sydney, Sydney, Australia.
Eur Arch Otorhinolaryngol. 2021 Jun;278(6):2057-2065. doi: 10.1007/s00405-020-06446-1. Epub 2020 Oct 28.
Parkinson's disease (PD) is a neurodegenerative disorder with possible vestibular system dysfunction. This study reports the transient and sustained functions of the otoliths and their reflex pathways in PD compared to healthy controls (HC) and determines if otolith function relates to previous fall history.
Forty participants with PD and 40 HC had their otolith function assessed. Transient saccular and utricular-mediated reflexes were assessed by cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs, respectively) elicited by air-conducted stimulus (clicks) and bone-conducted vibration (light tendon hammer taps). Static otolith function was assessed by the Curator Subjective Visual Vertical (SVV) test.
Compared to HC, the PD group had significantly more absent cVEMP responses to both clicks (47.5% vs. 30%, respectively, p = 0.03) and taps (21.8% vs. 5%, respectively, p = 0.002). Only the PD group had bilaterally absent tap cVEMPs, this was related to previous falls history (p < 0. 001). In both groups, click oVEMPs were predominantly absent, and tap oVEMPs were predominantly present. The PD group had smaller tap oVEMP amplitudes (p = 0.03) and recorded more abnormal SVV responses (p = 0.01) and greater error on SVV compared to HC, p < 0.001. SVV had no relationship with VEMP responses (p = 0.14).
PD impacts on cVEMP reflex pathways but not tap oVEMP reflex pathways. Bone-conducted otolith stimuli (taps) are more robust than air-conducted sound stimuli (clicks) for both o and cVEMPs. A lack of association between SVV and VEMP responses suggest that static and dynamic otolith functions are differentially affected in PD.
帕金森病（PD）是一种神经退行性疾病，可能伴有前庭系统功能障碍。本研究报告了与健康对照组（HC）相比，PD 患者的耳石瞬时和持续功能及其反射通路，并确定耳石功能是否与既往跌倒史有关。
40 名 PD 患者和 40 名 HC 参与者接受了耳石功能评估。通过颈源性和眼源性前庭诱发肌源性电位（cVEMPs 和 oVEMPs）评估短暂的球囊和椭圆囊介导的反射，刺激分别为气导刺激（click）和骨导振动（轻腱锤 tap）。静态耳石功能通过 Curator 主观视觉垂直（SVV）测试进行评估。
与 HC 相比，PD 组对 click 的 cVEMP 反应明显减少（分别为 47.5%和 30%，p=0.03），对 tap 的 cVEMP 反应明显减少（分别为 21.8%和 5%，p=0.002）。只有 PD 组双侧 tap cVEMPs 缺失，这与既往跌倒史有关（p<0.001）。在两组中，click oVEMPs 主要缺失，而 tap oVEMPs 主要存在。PD 组的 tap oVEMP 振幅较小（p=0.03），SVV 记录到更多异常反应（p=0.01），SVV 误差较大（p<0.001），与 HC 相比。SVV 与 VEMP 反应无相关性（p=0.14）。
PD 影响 cVEMP 反射通路，但不影响 tap oVEMP 反射通路。骨导耳石刺激（tap）比气导声刺激（click）对 o 和 cVEMPs 都更有效。SVV 与 VEMP 反应之间缺乏关联表明，PD 中静态和动态耳石功能受到不同影响。
