Dziemba Oliver C, Brzoska Tina, Hocke Thomas, Ihler Friedrich
Departement of Otorhinolarygology, Head and Neck Surgery, University Medicine Greifswald, 17475 Greifswald, Germany.
Cochlear Deutschland GmbH & Co. KG, 30539 Hannover, Germany.
J Clin Med. 2023 Nov 20;12(22):7188. doi: 10.3390/jcm12227188.
By using outcome prediction scores, it is possible to distinguish between good and poor performers with cochlear implants (CI) after CI implantation. The reasons for poor performance, despite good basic conditions, can be manifold. On the one hand, the postoperative fitting may be inadequate; on the other, neurophysiological disease processes may impair speech understanding with a CI. These disease processes are not yet fully understood. In acoustics, it is known that the auditory brainstem responses (ABR) and their latencies and amplitudes allow differential diagnosis based on reference values for normal-hearing individuals. The aim of this study was to provide reference values for electrically evoked brainstem responses (EABRs) in terms of rate-dependent latencies and amplitudes. 20 ears of 18 experienced adult CI recipients with a predicted and measured good postoperative word recognition score were recruited from the clinic's patient pool. In the same stimulation mode and intensity we measured latencies and interpeak-latencies of EABRs and electrically evoked compound action potentials (ECAPs). With a defined supra-threshold stimulation intensity above the individual ECAP threshold, we applied stimulation at several rates between 11 and 91 stimuli per second. We found rate dependences for EABR latency t3 and t5 in the order of 0.19 ms and 0.37 ms, respectively, while ECAP was not affected by rate. Correspondingly, the interpeak intervals' rate dependences for t5-t1, t5-t3 and t3-t1 were of the order of 0.37 ms, 0.18 ms and 0.19 ms. Comparing the EABR amplitudes between the stimulation rates 11/s and 81/s, we found that at 81/s the amplitudes were significantly reduced down: to 73% for A3 and 81% for A5. These rate dependences of latency and amplitude in EABR have characteristics comparable to those of acoustic ABR. These data may serve to provide reference values for EABR and ECAP latencies, interpeak intervals and amplitudes with respect to stimulation rate. Altered response patterns of ECAPs and EABRs to normalised stimulation modes could be used in the future to describe and classify neuropathological processes in a better-differentiated way.
通过使用结果预测分数,可以在人工耳蜗(CI)植入后区分CI使用者的表现优劣。尽管基本条件良好,但表现不佳的原因可能是多方面的。一方面,术后调试可能不充分;另一方面,神经生理疾病过程可能会损害CI的言语理解能力。这些疾病过程尚未完全明了。在声学领域,已知听觉脑干反应(ABR)及其潜伏期和振幅可基于正常听力个体的参考值进行鉴别诊断。本研究的目的是提供电诱发脑干反应(EABR)在频率依赖性潜伏期和振幅方面的参考值。从诊所的患者库中招募了18名经验丰富的成年CI使用者的20只耳朵,这些使用者术后单词识别分数经预测和测量均良好。在相同的刺激模式和强度下,我们测量了EABR以及电诱发复合动作电位(ECAP)的潜伏期和峰间潜伏期。在高于个体ECAP阈值的特定阈上刺激强度下,我们以每秒11至91次刺激的几种频率进行刺激。我们发现EABR潜伏期t3和t5的频率依赖性分别约为0.19毫秒和0.37毫秒,而ECAP不受频率影响。相应地,t5 - t1、t5 - t3和t3 - t1的峰间间隔频率依赖性约为0.37毫秒、0.18毫秒和0.19毫秒。比较11次/秒和81次/秒刺激频率下的EABR振幅,我们发现81次/秒时振幅显著降低:A3降低至73%,A5降低至81%。EABR潜伏期和振幅的这些频率依赖性具有与声学ABR相当的特征。这些数据可为EABR和ECAP潜伏期、峰间间隔及振幅相对于刺激频率提供参考值。未来,ECAP和EABR对标准化刺激模式的改变反应模式可用于以更好的区分方式描述和分类神经病理过程。