Arnold D J, Lonsbury-Martin B L, Martin G K
Department of Otolaryngology, University of Miami Ear Institute, Fla 33101, USA.
Arch Otolaryngol Head Neck Surg. 1999 Feb;125(2):215-22. doi: 10.1001/archotol.125.2.215.
The primary goal of this study was to test the ability of 2f1-f2 distortion-product otoacoustic emissions (DPOAEs) to detect reduced cochlear function in the presence of normal behavioral sensitivity.
A prospective study was performed in normal-hearing young adults using simple and complex regression analyses to clarify the relationship between ultra-high frequency (UHF) hearing and DPOAE levels at lower frequencies, as well as the influence of hearing levels for frequencies within the conventional test range and subject age on this association.
Average DPOAE levels between 4 to 8 kHz, which were elicited by equilevel primary tones of low to moderate levels, were measured as level-frequency functions, or distortion-product (DP) grams, and related to the mean UHF hearing levels from 11.2 to 20 kHz. The median hearing level for the UHF hearing was used to separate subjects into good and poor UHF hearers. This distinction was then used to compare DPOAE levels from 4 to 8 kHz for the 2 groups to determine if UHF hearing status influenced DPOAE levels at lower frequencies.
Simple regression analysis revealed that the 4-to 8-kHz DPOAE levels were significantly correlated with the pure-tone average (PTA) from 11.2 to 20 kHz. However, the PTA for 4 and 8 kHz was also significantly correlated with the PTA for UHF hearing. Further multiple regression analyses revealed that UHF hearing significantly and uniquely accounted for approximately 14% of the variance in DPOAE levels from 4 to 8 kHz for most of the primary-tone level combinations. In contrast, neither the PTA for the conventional hearing range nor subject age contributed significantly to the DPOAE variance.
The findings suggest that UHF hearing influences DPOAEs at significantly lower frequencies because emissions are sensitive to subtle changes in outer hair cells not yet detected by pure-tone thresholds in this region or because alterations in the basal cochlea affect the generation of lower-frequency DPOAEs originating from more apical cochlear regions.
本研究的主要目标是测试2f1-f2畸变产物耳声发射（DPOAE）在行为敏感度正常的情况下检测耳蜗功能减退的能力。
对听力正常的年轻成年人进行了一项前瞻性研究，使用简单和复杂回归分析来阐明超高频（UHF）听力与较低频率下DPOAE水平之间的关系，以及传统测试范围内频率的听力水平和受试者年龄对这种关联的影响。
测量由低至中等水平的等水平初级音诱发的4至8kHz之间的平均DPOAE水平，作为水平-频率函数或畸变产物（DP）图，并与11.2至20kHz的平均UHF听力水平相关。UHF听力的中位数听力水平用于将受试者分为UHF听力良好和较差的两组。然后利用这种区分来比较两组4至8kHz的DPOAE水平，以确定UHF听力状态是否会影响较低频率下的DPOAE水平。
简单回归分析显示，4至8kHz的DPOAE水平与11.2至20kHz的纯音平均听阈（PTA）显著相关。然而，4kHz和8kHz的PTA也与UHF听力的PTA显著相关。进一步的多元回归分析显示，对于大多数初级音水平组合，UHF听力显著且独特地解释了4至8kHz DPOAE水平约14%的方差。相比之下，传统听力范围的PTA和受试者年龄对DPOAE方差均无显著贡献。
研究结果表明，UHF听力会影响显著更低频率下的DPOAE，这是因为耳声发射对外毛细胞的细微变化敏感，而该区域的纯音阈值尚未检测到这些变化，或者是因为基底耳蜗的改变影响了源自耳蜗更顶端区域的低频DPOAE的产生。
