Objective: to observe the protective effect of sound preconditioning on hearing in acoustic trauma and explore the relevant mechanism with regard to free oxygen radicals in the cochlea.
目的：观察声预处理对噪声性听力损失的保护作用，并从氧自由基途径探讨其机制。
2
Conclusion: Prophylactic inhalation of negative air ions can increase the cochlear blood flow and promote microcirculation thus protecting the cochlea from acoustic trauma.
结论：预防性吸入空气负离子可增加耳蜗血流量，改善微循环，因而对保护噪声性耳蜗损伤是有益的。
3
Conclusion the earlier performance of acoustic neuroma is the abnormal function of cochlea and forecourt.