Ravazzani P, Grandori F
Systems Theory Centre (CNR), Polytechnic of Milan, Italy.
IEEE Trans Biomed Eng. 1993 May;40(5):500-4. doi: 10.1109/10.243410.
Evoked otoacoustic emissions (EOAE's) are acoustic signals produced by the inner ear in response to transient acoustic stimuli and can be recorded in the external auditory canal. Since emissions can be reduced or even abolished by hearing losses of peripheral origin due to trauma and pathology, EOAE's are presently considered as the most sensitive clinical test for assessing the integrity of peripheral hearing. Recordings of emissions evoked in response to transient stimuli are contaminated by an initial artifact which in most clinical environments can be a very serious limitation. For this reason, a nonlinear estimation method is widely used (derived nonlinear response, DNLR), instead of classical synchronous averaging. Aims of this paper are: i) to justify theoretically the use of the DNLR technique by means of a simple model; ii) to compare the results obtained from the classical averaging (a linear estimation technique) with those obtained from the nonlinear DNLR technique. Some suggestions of practical interest are finally inferred from present analysis.
诱发耳声发射（EOAE）是内耳对瞬态声刺激产生的声信号，可在外耳道记录。由于创伤和病理导致的外周性听力损失可使耳声发射减弱甚至消失，因此目前EOAE被认为是评估外周听力完整性最敏感的临床测试。瞬态刺激诱发的耳声发射记录会受到初始伪迹的干扰，在大多数临床环境中，这可能是一个非常严重的限制。因此，广泛使用非线性估计方法（派生非线性响应，DNLR），而不是传统的同步平均法。本文的目的是：i）通过一个简单模型从理论上证明DNLR技术的应用合理性；ii）将传统平均法（一种线性估计技术）得到的结果与非线性DNLR技术得到的结果进行比较。最后从当前分析中得出一些具有实际意义的建议。
