中文摘要：

目的研究新型光纤二氧化碳（CO2）激光行鼓膜造孔术的可行性及对内耳结构和功能的影响。方法 40只豚鼠随机分为4组（1、2、3 W和3 W＋生理盐水组）,前3组使用不同功率激光（1、2、3 W）在左耳鼓膜紧张部前下圆形造孔,第4组在左耳鼓室内注射生理盐水后再行3 W激光打孔。右耳均使用细针机械圆形造孔。比较各组穿孔愈合时间,术前和术后即刻、术后2周处死前行听性脑干反应检查了解听觉功能,术后2周行扫描电镜观察毛细胞超微结构的变化。结果 CO2激光造孔愈合时间较机械造孔明显延长（P〈0.01）;3 W组激光造孔后出现耳蜗局部炭化,听阈不可逆升高,耳蜗外毛细胞静纤毛倒伏和脱落。鼓室注射生理盐水后行3 W激光鼓膜打孔也出现听阈不可逆升高,但是术后2周听阈有部分恢复,耳蜗毛细胞损伤轻微。结论新型光纤CO2激光豚鼠鼓膜造孔术只要激光功率选择合适,临床治疗分泌性中耳炎伴有鼓室积液更安全、有效。

英文摘要：

Objective To explore the feasibility of fiber-enabled CO2 laser tympanostomy in guinea pigs and its influence on the structure and function of inner ear. Methods Forty guinea pigs were randomly divided into four groups. Guinea pigs belonging to the first three groups were treated with laser power（ 1,2,3 W） respectively for the left ear, while the forth group received intratympanic saline injection before 3W laser power. Laser treatment caused perforation on anterior inferior of pars tensa membrane tympani. Circular perforation was caused by needle for the fight ear in all groups as controls. Otoscopes examinations were performed to evaluate the healing time of perforation. Auditory brainstem response（ABR） were accessed preoperatively, immediately and 2 weeks postoperatively. Morphological changes of hair cells＇ microstructure were observed by scanning electron microscopy （SEM） 2 weeks postoperatively. Results The healing time of perforation of CO2 laser-caused perforation was longer than needle-caused perforation（P 〈0.01 ）. In 3 W CO2 laser treatment group, part of cochlea carbonized, ABR threshold increased irreversibly and stereoeilia of outer hair cells collapsed and disoriented. With previous intratympanic saline injection, ABR threshold increased immediately after laser perforation, but got partial restoration in 2 weeks with minor inner ear damage. Condusions The new fiber- enabled CO2 laser is effective and safe for secretory otitis media with effusion if the total amount of energy is kept within the limits.