Department of Otorhinolaryngology, University of São Paulo, Av. Dr. Eneas de Carvalho Aguiar, 255, São Paulo, SP 05403-000, Brazil.
Department of Otorhinolaryngology, University of São Paulo, Av. Dr. Eneas de Carvalho Aguiar, 255, São Paulo, SP 05403-000, Brazil.
Hear Res. 2021 May;404:108206. doi: 10.1016/j.heares.2021.108206. Epub 2021 Feb 18.
Cochlear implants (CI) programming is based on both the measurement of the minimum levels required to stimulate the auditory nerve and the maximum levels to generate loud, yet comfortable loudness. Seeking for guidance in the adequacy of this programming, the cortical auditory evoked potentials (CAEP) have been gaining space as an important tool in the evaluation of CI users, providing information on the central auditory system.
To evaluate the influence of mishandling of electrical stimulation levels on speech processor programming on hearing thresholds, speech recognition and cortical auditory evoked potential in adult CI users.
This is a prospective cross-sectional study, with a sample of adult unilateral CI users of both sexes, aged at least 18 years, post-lingual deafness, with minimum experience of 12 months of device use. Selected subjects should have average free field hearing thresholds with cochlear implant equal to or better than 34 dBHL and monosyllable recognition different from 0%. Individuals who could not collaborate with the procedures or who had no CAEP recordings were excluded. Participants were routinely programmed, and the map was named MO (optimized original map). Then three experimentally wrong maps were made: optimized original map with 10 current units below the maximum comfort level (C), named MC- (map minus C); optimized original map with minus 10 current units at minimum threshold level (T), named MT- (map minus T) and optimized original map with 10 current units above minimum level (T), named MT + (map plus T). In all programs, participants underwent free-field auditory thresholds from 250Hz to 6000Hz, recorded sentences and monosyllabic recognition tests presented at 65dB SPL in quiet and in noise, and free field CAEP evaluation. All tests were performed in an acoustically treated booth, in a randomized order of map presentation. Data were compared by Wilcoxon test.
Thirty individuals were selected and signed an informed consent form. The MC- map provided worsening of all free field thresholds, quiet and noise speech recognition, and P1 wave latency delay with significant difference from the results with the MO map. The MT- map worsened the hearing thresholds and statistically significantly reduced the P2 wave latency; MT+ map improved free field thresholds except 6000Hz, worsening speech recognition, without statistical significance.
The results suggest that maximum levels below the optimal thresholds lead to worse cochlear implant performance in both hearing thresholds and speech recognition tests in quiet and noise, increasing CAEP component P1 latency. On the other hand, the manipulation of minimum threshold levels showed alteration in audibility without significant impact on speech recognition.
人工耳蜗（CI）编程基于刺激听神经所需的最小水平和产生响亮但舒适的响度所需的最大水平。为了寻求对这种编程的充分性的指导，皮质听觉诱发电位（CAEP）作为 CI 用户评估的重要工具得到了越来越多的应用，为中枢听觉系统提供了信息。
评估成人 CI 用户在言语处理器编程中电刺激水平处理不当对听力阈值、言语识别和皮质听觉诱发电位的影响。
这是一项前瞻性的横断面研究，样本为成年单侧 CI 用户，男女不限，年龄至少 18 岁，后天失聪，设备使用经验至少 12 个月。选择的受试者应具有平均自由场听力阈值，双侧植入体听力阈值等于或优于 34dBHL，单音节识别率不同 0%。不能配合程序或没有 CAEP 记录的个体被排除在外。参与者被常规编程，图谱被命名为 MO（优化原始图谱）。然后制作了三个实验性错误图谱：在最大舒适水平（C）以下优化原始图谱 10 个电流单位，命名为 MC-（图谱减 C）；在最小阈值水平（T）下优化原始图谱减 10 个电流单位，命名为 MT-（图谱减 T）；在最小水平（T）上优化原始图谱加 10 个电流单位，命名为 MT+（图谱加 T）。在所有程序中，参与者进行了从 250Hz 到 6000Hz 的自由场听力阈值测试，在安静和噪声中以 65dB SPL 记录句子和单音节识别测试，并进行了自由场 CAEP 评估。所有测试均在隔音处理的播音室内进行，图谱呈现的顺序随机。通过 Wilcoxon 检验比较数据。
选择了 30 名个体并签署了知情同意书。MC-图谱导致所有自由场阈值、安静和噪声言语识别的恶化，与 MO 图谱相比，P1 波潜伏期延迟具有显著差异。MT-图谱恶化了听力阈值，并且 P2 波潜伏期有统计学意义的降低；MT+图谱改善了除 6000Hz 以外的自由场阈值，恶化了言语识别，但无统计学意义。
结果表明，最大水平低于最佳阈值会导致听力阈值和安静、噪声言语识别测试中的人工耳蜗性能恶化，增加 CAEP 成分 P1 潜伏期。另一方面，最小阈值水平的处理改变了可听度，而对言语识别没有显著影响。
