Szymańska Anna, Gryczyński Maciej, Pajor Anna
I Katedra Otolaryngologii, Uniwersytetu Medycznego w Łodzi, Uniwersyteckiego Szpitala Klinicznego nr 1 im. N. Barlickiego.
Otolaryngol Pol. 2008;62(6):735-9. doi: 10.1016/S0030-6657(08)70350-0.
One of the basic audiological parameter in estimation of hearing sensitivity is hearing threshold. The need for an objective tool to efficiently predict the audiogram caused that the use and importance of ASSR method is growing in recent times. However, the technique is quite new and needs to be still improved. Aim of the study was the estimation of behavioral audiogram in comparison with ABR and ASSR threshold of young adults with normal hearing.
The study sample included 9 subjects with normal hearing (18 ears) with no abnormalities in otoscopy. Behavioral hearing thresholds and ASSRs to carrier frequencies of 0.5, 1, 2, and 4 kHz were obtained. The ASSRs were assessed with Bio-logic MASTER system by the use of four sinusoidal tones both frequency--and amplitude--modulated given simultaneously to every ear for each carrier frequency. The potentials are collected, averaged and analyzed in this method by the fast Fourier transform to yield statistically significant responses. Electrophysiologic threshold responses for click ABR stimuli for the same carrier frequencies for right and left ear were obtained by the use of Bio-logic Navigator Pro unit. Differences and correlations between the ASSRs, ABRs and the behavioral thresholds were determined.
We discovered that the values of pure tone audiograms and ABRs thresholds values differ from ASSRs considerably. We could also observed that the difference between behavioral and ABRs threshold is less than for behavioral and ASSRs threshold.
To conclude, this study shows that auditory steady-state responses technique is not useful method in estimating of hearing threshold of young adults with normal hearing.
听力阈值是评估听力敏感度的基本听力学参数之一。由于需要一种客观工具来有效预测听力图，近年来，ASSR方法的应用和重要性日益增加。然而，该技术尚新，仍需改进。本研究的目的是比较听力正常的年轻成年人的行为听力图与ABR和ASSR阈值。
研究样本包括9名听力正常的受试者（18只耳），耳镜检查无异常。获得了对0.5、1、2和4kHz载波频率的行为听力阈值和ASSR。使用Bio-logic MASTER系统通过对每个载波频率同时向每只耳朵施加四个频率和幅度调制的正弦波来评估ASSR。通过快速傅里叶变换以这种方法收集、平均和分析电位，以产生具有统计学意义的反应。使用Bio-logic Navigator Pro装置获得左右耳相同载波频率的点击ABR刺激的电生理阈值反应。确定了ASSR、ABR与行为阈值之间的差异和相关性。
我们发现纯音听力图的值和ABR阈值与ASSR有很大差异。我们还可以观察到，行为阈值与ABR阈值之间的差异小于行为阈值与ASSR阈值之间的差异。
总之，本研究表明，听觉稳态反应技术在评估听力正常的年轻成年人的听力阈值方面不是一种有用的方法。
