Henderson D, Spongr V, Subramaniam M, Campo P
Hearing Research Laboratories Department of Communicative Disorders and Sciences, State University of New York, Buffalo 14214.
Hear Res. 1994 Jun 1;76(1-2):101-17. doi: 10.1016/0378-5955(94)90092-2.
Four groups of binaural chinchillas were exposed to impact noise (B-duration = 200 ms) ranging from 119 dB to 137 dB peak equivalent SPL at repetition rates of 1/s or 4/s. The duration of exposure was adjusted so that each exposure consisted of equal acoustic energy. Animals were then sacrificed immediately, 24 h or 30 days after the exposure and their cochleas subjected to scanning electron microscopy. For exposures of 119 dB or greater, there appeared to be direct mechanical damage, including large clefts between the third row of outer hair cells and Deiters' cells and fracture of tight cell junctions at the reticular lamina. There was also a progressive increase in cochlear damage over the 30 days of recovery. The patterns of cochlear pathology are compared with hearing losses and cochleograms of chinchillas previously subjected to similar exposures and with results of studies using higher level impulse noise. The results are discussed in terms of 'critical level' for impact and impulse noise.
将四组双耳雪貂暴露于峰值等效声压级在119分贝至137分贝之间、重复率为1次/秒或4次/秒的冲击噪声（B持续时间 = 200毫秒）中。调整暴露持续时间，以便每次暴露包含相等的声能。然后在暴露后立即、24小时或30天处死动物，并对其耳蜗进行扫描电子显微镜检查。对于119分贝或更高的暴露，似乎存在直接的机械损伤，包括第三排外毛细胞与Deiters细胞之间的大裂缝以及网状板处紧密细胞连接的断裂。在30天的恢复过程中，耳蜗损伤也逐渐增加。将耳蜗病理学模式与先前接受类似暴露的雪貂的听力损失和耳蜗电图进行比较，并与使用更高水平脉冲噪声的研究结果进行比较。根据冲击和脉冲噪声的“临界水平”对结果进行了讨论。
