Division of Otorhinolaryngology, Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Prêto, SP, 14049-900, Brazil.
Eur Arch Otorhinolaryngol. 2011 Jan;268(1):49-56. doi: 10.1007/s00405-010-1338-4. Epub 2010 Jul 21.
Acute acoustic trauma (AAT) is a sudden sensorineural hearing loss caused by exposure of the hearing organ to acoustic overstimulation, typically an intense sound impulse, hyperbaric oxygen therapy (HOT), which favors repair of the microcirculation, can be potentially used to treat it. Hence, this study aimed to assess the effects of HOT on guinea pigs exposed to acoustic trauma. Fifteen guinea pigs were exposed to noise in the 4-kHz range with intensity of 110 dB sound level pressure for 72 h. They were assessed by brainstem auditory evoked potential (BAEP) and by distortion product otoacoustic emission (DPOAE) before and after exposure and after HOT at 2.0 absolute atmospheres for 1 h. The cochleae were then analyzed using scanning electron microscopy (SEM). There was a statistically significant difference in the signal-to-noise ratio of the DPOAE amplitudes for the 1- to 4-kHz frequencies and the SEM findings revealed damaged outer hair cells (OHC) after exposure to noise, with recovery after HOT (p = 0.0159), which did not occur on thresholds and amplitudes to BAEP (p = 0.1593). The electrophysiological BAEP data did not demonstrate effectiveness of HOT against AAT damage. However, there was improvement of the anatomical pattern of damage detected by SEM, with a significant reduction of the number of injured cochlear OHC and their functionality detected by DPOAE.
急性声创伤（AAT）是由于听觉器官暴露于声过度刺激下，通常是强烈的声音脉冲引起的突发性感觉神经性听力损失。高压氧治疗（HOT）有利于修复微循环，可潜在用于治疗 AAT。因此，本研究旨在评估 HOT 对暴露于声创伤的豚鼠的影响。15 只豚鼠在 4 kHz 范围内暴露于 110 dB 声压级的噪声中 72 h。它们在暴露前后以及在 2.0 绝对大气压下进行 1 h HOT 后，通过脑干听觉诱发电位（BAEP）和畸变产物耳声发射（DPOAE）进行评估。然后使用扫描电子显微镜（SEM）分析耳蜗。1-4 kHz 频率的 DPOAE 幅度的信噪比存在统计学差异，并且 SEM 结果显示暴露于噪声后外毛细胞（OHC）受损，HOT 后恢复（p=0.0159），但 BAEP 的阈值和幅度没有恢复（p=0.1593）。电生理 BAEP 数据并未显示 HOT 对 AAT 损伤的有效性。然而，通过 SEM 检测到的解剖学损伤模式有所改善，DPOAE 检测到受损耳蜗 OHC 的数量及其功能显著减少。
