Pediatric Audiology and Cochlear Implant Program, University of California at San Francisco Benioff Children's Hospital Oakland, Oakland, California, USA.
Research and Technology Department, Advanced Bionics, California, USA.
Ear Hear. 2020 Sep/Oct;41(5):1320-1326. doi: 10.1097/AUD.0000000000000870.
In adult cochlear implant patients, conventional audiometry is used to measure postoperative residual hearing which requires active listening and patient feedback. However, audiological measurements in pediatric cochlear implant patients are both challenging as well as time consuming. Intracochlear electrocochleography (ECOG) offers an objective and a time-efficient method to measure frequency-specific cochlear microphonic or difference thresholds (CM/DIF) thresholds that closely approximate auditory thresholds in adult cochlear implant patients. The correlation between CM/DIF and behavioral thresholds has not been established in pediatric cochlear implant patients. In the present study, CM/DIF thresholds were compared with audiometric thresholds in pediatric cochlear implant patients with postoperative residual hearing.
Thirteen (11 unilateral and 2 bilateral) pediatric cochlear implant patients (mean age = 9.2 years ± 5.1) participated in this study. Audiometric thresholds were estimated using conventional, condition play, or visual reinforcement audiometry. A warble tone stimulus was used to measure audiometric thresholds at 125, 250, 500, 1000, and 2000 Hz. ECOG waveforms were elicited using 50-msec acoustic tone-bursts. The most apical intracochlear electrode was used as the recording electrode with an extra-cochlear ground electrode. The ECOG waveforms were analyzed to determine CM/DIF thresholds that were compared with pediatric cochlear implant patients' audiometric thresholds.
The results show a significant correlation (r = 0.77, p < 0.01) between audiometric and CM/DIF thresholds over a frequency range of 125 to 2000 Hz in pediatric cochlear implant patients. Frequency-specific comparisons revealed a correlation of 0.82, 0.74, 0.69, 0.41, and 0.32 between the audiometric thresholds and CM/DIF thresholds measured at 125, 250, 500, 1000, and 2000 Hz, respectively. An average difference of 0.4 dB (±14 dB) was measured between the audiometric and CM/DIF thresholds.
Intracochlear ECOG can be used to measure CM/DIF thresholds in pediatric cochlear implant patients with residual hearing in the implanted ear. The CM/DIF thresholds are similar to the audiometric thresholds at lower test frequencies and offer an objective method to monitor residual hearing in difficult-to-test pediatric cochlear implant patients.
在成人耳蜗植入患者中，常规听力测试用于测量术后残余听力，这需要患者主动参与并提供反馈。然而，儿童耳蜗植入患者的听力测量既具有挑战性，又耗时。耳蜗内电描记法（ECOG）提供了一种客观且高效的方法来测量频率特异性耳蜗微音或差异阈值（CM/DIF），这些阈值与成人耳蜗植入患者的听觉阈值非常接近。CM/DIF 与行为阈值之间的相关性尚未在儿童耳蜗植入患者中建立。在本研究中，将 CM/DIF 阈值与具有术后残余听力的儿童耳蜗植入患者的听力阈值进行了比较。
13 名（11 名单侧和 2 名双侧）儿童耳蜗植入患者（平均年龄=9.2 岁±5.1 岁）参与了这项研究。使用常规、条件播放或视觉强化听力测试来估计听力阈值。使用颤音刺激来测量 125、250、500、1000 和 2000 Hz 的听力阈值。使用 50 毫秒的声脉冲刺激来引出 ECOG 波形。最顶端的耳蜗内电极用作记录电极，另一个额外的耳蜗外电极用作接地电极。分析 ECOG 波形以确定 CM/DIF 阈值，并与儿童耳蜗植入患者的听力阈值进行比较。
结果显示，在儿童耳蜗植入患者的 125 至 2000 Hz 频率范围内，听力阈值与 CM/DIF 阈值之间存在显著相关性（r=0.77，p<0.01）。频率特异性比较显示，在 125、250、500、1000 和 2000 Hz 处测量的听力阈值与 CM/DIF 阈值之间的相关性分别为 0.82、0.74、0.69、0.41 和 0.32。测量的听力阈值与 CM/DIF 阈值之间的平均差值为 0.4 dB（±14 dB）。
在具有植入耳残余听力的儿童耳蜗植入患者中，可以使用耳蜗内 ECOG 测量 CM/DIF 阈值。CM/DIF 阈值与较低测试频率的听力阈值相似，为监测难以测试的儿童耳蜗植入患者的残余听力提供了一种客观方法。
