Department of Communication Sciences and Disorders, Wichita State University, 1845 Fairmount Street, Wichita, Kansas 67260-0075, USA.
J Acoust Soc Am. 2013 Jul;134(1):332-41. doi: 10.1121/1.4807509.
The wideband energy reflectance (ER) technique has become popular as a tool for evaluating middle ear function. Negative middle ear pressure (MEP) is a prevalent form of middle ear dysfunction, which may impact application of ER measurements in differential diagnosis. A negative MEP may be countervailed by application of an equivalent negative ear canal pressure. The present study examined ER in the same ears under normal and experimentally induced negative MEP conditions. Thirty-five subjects produced at least one negative MEP each (-40 to -225 daPa). Negative MEP significantly altered ER in a frequency-specific manner that varied with MEP magnitude. ER increased for low- to mid-frequencies with the largest change (0.20 to 0.40) occurring between 1 and 1.5 kHz. ER decreased for frequencies above 3 kHz with the largest change (-0.10 to -0.25) observed between 4.5 and 5.5 kHz. Magnitude of changes increased as MEP became more negative, as did the frequencies at which maximum changes occurred, and the frequency at which enhancement transitioned to reduction. Ear canal pressure compensation restored ER to near baseline values. This suggests that the compensation procedure adequately mitigates the effects of negative MEP on ER. Theoretical issues and clinical implications are discussed.
宽频带能量反射率（ER）技术已成为评估中耳功能的一种流行工具。负中耳压力（MEP）是中耳功能障碍的一种常见形式，可能会影响 ER 测量在鉴别诊断中的应用。负 MEP 可以通过施加等效的负耳道压力来抵消。本研究在正常和实验性负 MEP 条件下检查了同一耳朵的 ER。35 名受试者每人至少产生了一次负 MEP（-40 至-225 达帕）。负 MEP 以随 MEP 幅度变化的特定频率方式显著改变 ER。ER 在低频到中频增加，最大变化约为 0.20 至 0.40，发生在 1 至 1.5 kHz 之间。高于 3 kHz 的频率 ER 降低，最大变化约为-0.10 至-0.25，发生在 4.5 至 5.5 kHz 之间。随着 MEP 变得更负，变化幅度增大，最大变化发生的频率以及增强过渡到降低的频率也增大。耳道压力补偿将 ER 恢复到接近基线值。这表明补偿程序足以减轻负 MEP 对 ER 的影响。讨论了理论问题和临床意义。
