Rydmarker S, Nilsson P, Dunn D E, Lindqvist C
Department of Otolaryngology, Malmö General Hospital, University of Lund, Sweden.
Scanning Microsc. 1989 Dec;3(4):1253-64.
Many investigations of noise-induced hearing loss have demonstrated a poor correlation between hearing threshold and hair cell loss. One reason for this is that more subtle changes in the hair cell, such as detailed morphological changes of stereocilia, have not been evaluated. However, examining such changes increases the problem of distinguishing experimental pathological changes from artefacts. Preparation of the specimen for scanning electron microscopy (SEM) may result in too many artefacts for an adequate quantification of defects due to noise exposure. One problem with some earlier studies seems to be lack of controls and/or statistical analysis for the purpose of eliminating the influence of artefacts and spontaneous degeneration. The aim of this study was to compare unexposed and noise-exposed cochleas examined with SEM in order to determine if subtle changes due to noise could be distinguished from preparation artefacts and from spontaneous deterioration. Ten different types of hair cell changes were found in exposed and control animals. By means of using controls for statistical comparison with noise-exposed animals two cell damage categories--hair cell loss and missing stereocilia--were found to be produced by exposure to noise.
许多关于噪声性听力损失的研究表明，听力阈值与毛细胞损失之间的相关性较差。造成这种情况的一个原因是，毛细胞中更细微的变化，如静纤毛的详细形态变化，尚未得到评估。然而，检查此类变化会增加区分实验性病理变化与假象的难度。用于扫描电子显微镜（SEM）检查的标本制备可能会产生过多假象，从而无法充分量化噪声暴露导致的缺陷。一些早期研究存在的一个问题似乎是缺乏用于消除假象和自发退化影响的对照和/或统计分析。本研究的目的是比较通过SEM检查的未暴露和噪声暴露的耳蜗，以确定噪声引起的细微变化是否可以与制备假象和自发退化区分开来。在暴露组和对照组动物中发现了十种不同类型的毛细胞变化。通过使用对照组与噪声暴露动物进行统计比较，发现暴露于噪声会导致两种细胞损伤类型——毛细胞损失和静纤毛缺失。
