Singh Niraj Kumar, Apeksha Kumari
Department of Audiology, All India Institute of Speech and Hearing, Manasagangothri, Mysore, 570006, Karnataka, India.
Eur Arch Otorhinolaryngol. 2016 Sep;273(9):2523-32. doi: 10.1007/s00405-015-3867-3. Epub 2015 Dec 30.
Benign paroxysmal positional vertigo (BPPV) constitutes a major proportion of the population with peripheral vestibulopathies. Although the freely floating otoconia within the semicircular canals is responsible for the symptoms of BPPV, the source of the otoconia debris is mainly believed to be the otolith organs. Therefore, the pathology in either or both the otolith organs appears a logical proposition. Cervical and ocular vestibular-evoked myogenic potentials (cVEMP and oVEMP), being the tests for functional integrity of the otolith organs, appear promising for investigating otolith involvement in BPPV. While recent evidences are suggestive of equivocal findings for cVEMP, there are only a few studies on oVEMP. Additionally, both these potentials have never been explored in the same set of individuals with BPPV. Therefore, the present study aimed to evaluate the functional integrity of the otolith organs through cVEMP and oVEMP in individuals with posterior canal BPPV. Thirty-one individuals with unilateral posterior canal BPPV and 31 age- and gender-matched healthy controls underwent 500 Hz tone-burst-evoked cVEMP and oVEMP. The results demonstrated no significant group difference on any of the cVEMP parameters (p > 0.05). A similar trend was noticed for the latency-related parameters of oVEMP. However, the peak-to-peak amplitude was significantly smaller in the affected ears of individuals with BPPV than their unaffected ears and the ears of healthy controls (p < 0.05). The BPPV group showed significantly higher inter-aural amplitude difference ratio than the healthy controls (p < 0.05). Further, the sensitivity and specificity of oVEMP were also found to be far superior to those of cVEMP. Thus, the outcome of the present study revealed involvement of utricle rather than saccule in posterior canal BPPV, and therefore, oVEMP appears to be better suited to clinical investigation than cVEMP in individuals with posterior canal BPPV.
良性阵发性位置性眩晕（BPPV）在周围性前庭病变人群中占很大比例。尽管半规管内自由漂浮的耳石是BPPV症状的起因，但耳石碎片的来源主要被认为是耳石器。因此，耳石器单耳或双耳的病变似乎是一个合理的推断。颈前庭诱发肌源性电位（cVEMP）和眼前庭诱发肌源性电位（oVEMP）作为检测耳石器功能完整性的测试，在研究耳石器与BPPV的关系方面似乎很有前景。虽然最近的证据表明cVEMP的结果存在矛盾，但关于oVEMP的研究却很少。此外，从未在同一组BPPV患者中对这两种电位进行过研究。因此，本研究旨在通过cVEMP和oVEMP评估后半规管BPPV患者耳石器的功能完整性。31名单侧后半规管BPPV患者和31名年龄及性别匹配的健康对照者接受了500Hz短纯音诱发的cVEMP和oVEMP检测。结果显示，cVEMP的任何参数在两组之间均无显著差异（p>0.05）。oVEMP的潜伏期相关参数也呈现类似趋势。然而，BPPV患者患耳的峰峰值振幅明显小于其未患耳及健康对照者的耳朵（p<0.05）。BPPV组的双耳振幅差异比显著高于健康对照组（p<0.05）。此外，还发现oVEMP的敏感性和特异性远优于cVEMP。因此，本研究结果表明后半规管BPPV累及的是椭圆囊而非球囊，所以，在患有后半规管BPPV的个体中，oVEMP似乎比cVEMP更适合用于临床研究。
