Emerita, Department of Head and Neck Surgery, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA.
C & Y Consultants, Santa Fe, New Mexico, USA.
Ear Hear. 2018 Nov/Dec;39(6):1207-1223. doi: 10.1097/AUD.0000000000000580.
The first objective of this study was to compare the predicted audiometric thresholds obtained by auditory steady state response (ASSR) and auditory brainstem response (ABR) in infants and toddlers when both techniques use optimal stimuli and detection algorithms. This information will aid in determining the basis for large discrepancies in ABR and ASSR measures found in past studies. The hypothesis was that advancements in ASSR response detection would improve (lower) thresholds and decrease discrepancies between the thresholds produced by the two techniques. The second objective was to determine and compare test times required by the two techniques to predict thresholds for both ears at the 4 basic audiometric frequencies of 500, 1000, 2000, and 4000 Hz.
A multicenter clinical study was implemented at three university-based children's hospital audiology departments. Participants were 102 infants and toddlers referred to the centers for electrophysiologic testing for audiometric purposes. The test battery included wideband tympanometry, distortion-product otoacoustic emissions, and threshold measurements at four frequencies in both ears using ABR and ASSR (randomized) as implemented on the Interacoustics Eclipse systems with "Next-Generation" ASSR detection and FMP analysis for ABR. Both methods utilized narrow band CE-Chirp stimuli. Testers were trained on a specialized test battery designed to minimize test time for both techniques. Testing with both techniques was performed in one session. Thresholds were evaluated and confirmed by the first author and correction factors were applied. Test times were documented in system software.
Corrected thresholds for ABR and ASSR were compared by regression, by the Bland-Altman technique and by matched pairs t tests. Thresholds were significantly lower for ASSR than ABR. The ABR-ASSR discrepancy at 500 Hz was 14.39 dB, at 1000 Hz was 10.12 dB, at 2000 Hz was 3.73 dB, and at 4000 Hz was 3.67 dB. The average test time for ASSR of 19.93 min (for 8 thresholds) was found to be significantly lower (p < 0.001) than the ABR test time of 32.15 min. One half of the subjects were found to have normal hearing. ASSR thresholds plotted in dB nHL for normal-hearing children in this study were found to be the lowest yet described except for one study which used the same technology.
This study found a reversal of previous findings with up to 14 dB lower thresholds found when using the ASSR technique with "Next-Generation" detection as compared with ABR using an automated detection (FMP). The test time for an audiogram prediction was significantly lower when using ASSR than ABR but was excellent by clinical standards for both techniques. ASSRs improved threshold performance was attributed to advancements in response detection including utilization of information at multiple harmonics of the modulation frequency. The stimulation paradigm which utilized narrow band CE-Chirps also contributed to the low absolute levels of the thresholds in nHL found with both techniques.
本研究的首要目的是比较在两种技术均采用最优刺激和检测算法时，婴儿和幼儿的听觉稳态反应（ASSR）和听性脑干反应（ABR）预测听力阈值的情况。这一信息将有助于确定在过去的研究中发现的 ABR 和 ASSR 测量值之间存在较大差异的原因。该假设是，ASSR 反应检测的进步将改善（降低）阈值，并减少两种技术产生的阈值之间的差异。第二个目的是确定和比较这两种技术预测双耳在 500、1000、2000 和 4000 Hz 四个基本听力频率的阈值所需的测试时间。
在三个大学附属儿童医院的听力科实施了一项多中心临床研究。参与者是 102 名因听力目的而被推荐到中心进行电生理测试的婴儿和幼儿。测试组合包括宽带鼓室图、畸变产物耳声发射和双耳四个频率的阈值测量，ABR 和 ASSR（随机）在 Interacoustics Eclipse 系统上实施，该系统具有“下一代”ASSR 检测和 FMP 分析用于 ABR。两种方法均使用窄带 CE-Chirp 刺激。测试人员接受了专门设计的测试组合的培训，旨在最大限度地减少两种技术的测试时间。两种技术的测试均在一次会议中进行。由第一作者评估和确认阈值，并应用校正因子。测试时间记录在系统软件中。
通过回归、Bland-Altman 技术和匹配对 t 检验比较了 ABR 和 ASSR 的校正阈值。ASSR 的阈值明显低于 ABR。500 Hz 时 ABR-ASSR 差异为 14.39 dB，1000 Hz 时为 10.12 dB，2000 Hz 时为 3.73 dB，4000 Hz 时为 3.67 dB。ASSR 的平均测试时间为 19.93 分钟（8 个阈值），发现明显低于 ABR 的测试时间 32.15 分钟（p < 0.001）。一半的受试者被发现听力正常。本研究中，听力正常的儿童的 ASSR 阈值以 dB nHL 绘制，发现除了一项使用相同技术的研究外，这是迄今为止描述的最低阈值。
本研究发现，与使用自动检测（FMP）的 ABR 相比，当使用具有“下一代”检测的 ASSR 技术时，阈值降低了多达 14 dB，这与以往的发现相反。使用 ASSR 预测听力图的测试时间明显低于 ABR，但两种技术的临床标准都非常出色。ASSR 提高了阈值性能，这归因于反应检测的进步，包括利用调制频率的多个谐波的信息。使用窄带 CE-Chirps 的刺激范式也有助于两种技术在 nHL 中发现的低绝对阈值水平。
