中等强度冲击波负压暴露后豚鼠内耳损伤的治疗

Treatment of inner-ear impact injuries caused by mid-intensity blast underpressure in guinea pigs

目的 探讨豚鼠中等强度冲击波负压重复暴露后，高压氧和（或）地塞米松＋甲钴铵对内耳损伤的治疗效果。方法 32只豚鼠于实验性冲击波负压重复暴露3次后，立即分别给予高压氧治疗、肌注地塞米松＋甲钴胺治疗、肌注地塞米松＋甲钴胺＋高压氧治疗，对照组不接受任何治疗。各治疗组动物于治疗前、治疗后2小时-21天分别测试听性脑干反应（ABR）阈值，在光镜和扫描电镜下观察耳蜗毛细胞形态学改变，并将其与对照组进行对比分析。结果 实验性冲击波负压重复暴露后即刻，各治疗组动物ABR阈值明显升高（P〈0．01），治疗21天后呈部分恢复。治疗21天后，各治疗组动物耳蜗毛细胞缺失少于对照组。在上述3种治疗方案中，以地塞米松＋甲钴胺＋高压氧联合应用对听器损伤的治疗效果最为明显。结论 在中等强度冲击波负压重复暴露造成豚鼠内耳损伤后，及时给予高压氧吸入及地塞米松和甲钴胺2种药物联合治疗，可有效促进听力功能的恢复并减轻耳蜗毛细胞损害程度。

Objective To study the treatment of hyperbaric oxygen combined with dexamethasone and methylcobalamin on inner-ear impact injury caused by mid-intensity blast underpressure （ BUP ） in guinea pigs. Methods Thirty-two guinea pigs were exposed repeatedly to experimental blast underpressure for 3 times, and then the treatment of hyperbaric oxygen, dexamethasone ＋ methylcobalamin, hyperbaric oxygen combined with dexamethasone and methylcobalamin were taken immediately. The control guoup were not given any kind of the above therapy. Threshold of auditory brain response （ABR） of 4 groups were respectively measured before and 2h-21 d after exposure. Morphological changes of the cochlear hair cell of treatment groups were also observed with light microscope and scanning electric microscope, which were compared to that of the control group. Results The ABR threshold of the treantment groups were significantly elevated immediately following the underprsseure exposure （ P 〈 0.01 ） , which was partially recovered after 21d treatment. The degree of severity of cochlear hair cells injury of the experimental groups was less than that of the control group after 21 d treatment. The loss of cochlear hair cells reduced in experimental groups as compared to the control group. Compared to the other 2 types of treatment, the treatment with hyperbaric oxygen combined with dexamethasone and methylcobalamin had the best protective effect on auditory hair cell. Conclusion The results suggested that hyperbaric oxygen combined with dexamethasone and methylcobalamin is the best method of treatment for inner ear impact injury.