Harris Michael S, Riggs William J, Giardina Christopher K, O'Connell Brendan P, Holder Jourdan T, Dwyer Robert T, Koka Kanthaiah, Labadie Robert F, Fitzpatrick Douglas C, Adunka Oliver F
*Department of Otolaryngology-Head and Neck Surgery and Nationwide Children's Hospital, The Ohio State University Wexner Medical Center, Columbus, Ohio †Department of Otolaryngology-Head and Neck Surgery, University of North Carolina, Chapel Hill, North Carolina ‡Department of Otolaryngology-Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, Tennessee §Advanced Bionics Corporation, Valencia, California.
Otol Neurotol. 2017 Dec;38(10):1415-1420. doi: 10.1097/MAO.0000000000001559.
Intraoperative, intracochlear electrocochleography (ECochG) will provide a means to monitor cochlear hair cell and neural response during cochlear implant (CI) electrode insertion. Distinct patterns in the insertion track can be characterized.
Conventional CI surgery is performed without a means of actively monitoring cochlear hair cell and neural responses. Intracochlear ECochG obtained directly through the CI may be a source of such feedback. Understanding the patterns observed in the "insertion track" is an essential step toward refining intracochlear ECochG as a tool that can be used to assist in intraoperative decision making and prognostication of hearing preservation.
Intracochlear ECochG was performed in 17 patients. During electrode insertion, a 50-ms tone burst acoustic stimulus was delivered with a frequency of 500 Hz at 110 dB SPL. The ECochG response was monitored from the apical-most electrode. The amplitude of the first harmonic was plotted and monitored in near real time by the audiologist-surgeon team during CI electrode insertion.
Three distinct patterns in first harmonic amplitude change were observed across subjects during insertion: Type A (52%), overall increase in amplitude from the beginning of insertion until completion; Type B (11%), a maximum amplitude at the beginning of insertion, with a decrease in amplitude as insertion progressed to completion; and Type C (35%), comparable amplitudes at the beginning and completion of the insertion with the maximum amplitude mid-insertion.
Three ECochG patterns were observed during electrode advancement into the cochlea. Ongoing and future work will broaden our scope of knowledge regarding the relationship among these patterns, the presence of cochlear trauma, and functional outcomes related to hearing preservation.
术中经耳蜗内进行的电耳蜗图（ECochG）将提供一种手段，以监测人工耳蜗（CI）电极插入过程中的耳蜗毛细胞和神经反应。插入轨迹中的不同模式可以被表征。
传统的CI手术在没有主动监测耳蜗毛细胞和神经反应手段的情况下进行。直接通过CI获得的耳蜗内ECochG可能是这种反馈的一个来源。了解在“插入轨迹”中观察到的模式是将耳蜗内ECochG完善为一种可用于辅助术中决策和听力保留预后评估工具的关键一步。
对17例患者进行了耳蜗内ECochG检查。在电极插入过程中，以110 dB SPL的强度、500 Hz的频率给予50 ms的短纯音声刺激。从最顶端的电极监测ECochG反应。在CI电极插入过程中，听力学家-外科医生团队以近实时的方式绘制并监测一次谐波的振幅。
在插入过程中，不同受试者观察到一次谐波振幅变化的三种不同模式：A型（52%），从插入开始到完成振幅总体增加；B型（11%），插入开始时振幅最大，随着插入进展到完成振幅减小；C型（35%），插入开始和完成时振幅相当，最大振幅出现在插入中间阶段。
在电极推进到耳蜗的过程中观察到了三种ECochG模式。正在进行的和未来的工作将拓宽我们对这些模式、耳蜗创伤的存在以及与听力保留相关的功能结果之间关系的认识范围。
