Veterans Affairs (VA) Rehabilitation Research & Development Service (RR&D) National Center for Rehabilitative Auditory Research (NCRAR), VA Portland Health Care System Portland, Oregon 97239, USA.
J Acoust Soc Am. 2021 Dec;150(6):4440. doi: 10.1121/10.0007484.
Although clinical use of the auditory brainstem response (ABR) to detect retrocochlear disorders has been largely replaced by imaging in recent years, the discovery of cochlear synaptopathy has thrown this foundational measure of auditory function back into the spotlight. Whereas modern imaging now allows for the noninvasive detection of vestibular schwannomas, imaging technology is not currently capable of detecting cochlear synaptopathy, the loss of the synaptic connections between the inner hair cells and afferent auditory nerve fibers. However, animal models indicate that the amplitude of the first wave of the ABR, a far-field evoked potential generated by the synchronous firing of auditory nerve fibers, is highly correlated with synaptic integrity. This has led to many studies investigating the use of the ABR as a metric of synaptopathy in humans. However, these studies have yielded mixed results, leading to a lack of consensus about the utility of the ABR as an indicator of synaptopathy. This review summarizes the animal and human studies that have investigated the ABR as a measure of cochlear synaptic function, discusses factors that may have contributed to the mixed findings and the lessons learned, and provides recommendations for future use of this metric in the research and clinical settings.
尽管近年来，影像学在检测耳蜗后疾病方面的临床应用已在很大程度上取代了听觉脑干反应（ABR），但耳蜗突触病的发现又使这种听觉功能的基本测量方法重新成为焦点。虽然现代影像学现在可以无创地检测前庭神经鞘瘤，但成像技术目前还无法检测耳蜗突触病，即内毛细胞和传入听神经纤维之间的突触连接的丧失。然而，动物模型表明，ABR 的第一个波的幅度（由听神经纤维同步放电产生的远场诱发电位）与突触完整性高度相关。这导致了许多研究探索使用 ABR 作为人类突触病的指标。然而，这些研究的结果喜忧参半，导致人们对 ABR 作为突触病指标的实用性缺乏共识。这篇综述总结了研究 ABR 作为耳蜗突触功能测量指标的动物和人类研究，讨论了可能导致混合结果的因素以及从中吸取的教训，并为该指标在研究和临床环境中的未来应用提供了建议。
