Keefe D H
Boys Town National Research Hospital, Omaha, Nebraska 68131, USA.
J Acoust Soc Am. 1997 Nov;102(5 Pt 1):2849-59. doi: 10.1121/1.420340.
Otoreflectance refers to acoustic pressure reflectance measurements in the ear canal, by the use of a leak-free insertion of a probe assembly, in the frequency or time domain over a range of two or more stimulus levels. Otoreflectance includes an iso-level response indicative of the forward transfer of acoustic energy into the middle ear, and nonlinear responses indicative of the acoustic energy reflected back from the cochlea. The nonlinear otoreflectance decouples the reflected energy in an evoked otoacoustic emission (OAE) from its subsequent re-reflected energy due to the presence of the ear-canal probe. Nonlinear otoreflectance responses are extremely sensitive to probe distortion, and a double-evoked (2E) technique, previously used in evoked (OAE) measurements, is adapted for otoreflectance to solve the distortion problem. Results are obtained using a 2E stimulus set containing a set of three click stimuli delivered through a pair of sources. The corresponding sets of three pressure responses are acquired in a calibration tube, and in the ear canal, and a set of three iso-level ear-canal reflectances is calculated. An evoked OAE can be decomposed into a otoacoustic reflected pressure (ORP), and a nonlinear otoreflectance is defined by the ratio of the ORP to the initial pressure spectrum. Otoreflectance provides simultaneous measurements of middle-ear and cochlear responses, and has potential, as yet untested, for application to clinical tests for hearing impairments.
耳反射率是指通过无泄漏插入探头组件，在耳道内进行的声压反射率测量，测量在频率域或时间域内，跨越两个或更多刺激水平的范围。耳反射率包括指示声能向前传入中耳的等水平响应，以及指示从耳蜗反射回声能的非线性响应。由于耳道探头的存在，非线性耳反射率将诱发耳声发射（OAE）中的反射能量与其随后的再反射能量解耦。非线性耳反射率响应对探头失真极为敏感，并且一种先前用于诱发（OAE）测量的双诱发（2E）技术被应用于耳反射率测量，以解决失真问题。使用包含通过一对声源传递的一组三个咔嗒声刺激的2E刺激集来获得结果。在校准管中和耳道中采集相应的三组压力响应，并计算一组三个等水平耳道反射率。诱发的OAE可以分解为耳声反射压力（ORP），并且非线性耳反射率由ORP与初始压力谱的比值定义。耳反射率可同时测量中耳和耳蜗的响应，并且在应用于听力障碍的临床测试方面具有尚未经过测试的潜力。
