Sand T, Saunte C
Department of Neurology, University Hospital of Trondheim, Norway.
Scand Audiol. 1994;23(1):7-12. doi: 10.3109/01050399409047482.
ABR amplitude behaviour to condensation (C) and rarefaction (R) clicks was investigated in normal ears, ears affected by Ménière's disease and ears with high-frequency hearing loss (HF ears). The wave IV-V amplitude-intensity function was steeper in ABRs evoked by R than by C clicks. This may suggest that two different cochlear generator components, one intensity-dependent as well as one polarity-dependent, contribute to click-evoked ABRs. Wave IV-V amplitude was significantly higher in Ménière ears compared to HF ears in spite of comparable 2-4 kHz hearing loss in the two groups. Hence, audiometric steepness (which is lower in Ménière ears than in HF ears) seems to predict the wave IV-V amplitude decline more precisely than the 2-4 kHz perception threshold. The wave IV-V dispersion variable (SR IV-V) was close to normal in Ménière ears, while wave IV-V was more dispersed in HF ears. In general, C click ABRs were less affected than R click ABRs by 'peripheral' factors (i.e. intensity and audiometric steepness).
在正常耳、梅尼埃病耳和高频听力损失耳（HF耳）中，研究了听性脑干反应（ABR）对短纯音疏波（R）和密波（C）刺激的波幅变化情况。由R短纯音引出的ABR中，波IV-V的波幅-强度函数比由C短纯音引出的更陡峭。这可能表明，两种不同的耳蜗发生器成分，一种与强度有关，另一种与极性有关，共同促成了短纯音诱发的ABR。尽管两组的2-4kHz听力损失程度相当，但梅尼埃病耳的波IV-V波幅明显高于HF耳。因此，听力计斜率（梅尼埃病耳比HF耳更低）似乎比2-4kHz的听阈更能准确预测波IV-V波幅的下降。梅尼埃病耳的波IV-V离散变量（SR IV-V）接近正常，而HF耳的波IV-V离散度更大。一般来说，“外周”因素（即强度和听力计斜率）对C短纯音ABR的影响小于对R短纯音ABR的影响。
