二氧化碳激光鼓膜切开术的实验研究

目的：研究CO2激光鼓膜切开术的治疗能力及鼓膜的组织学变化。方法：25只豚鼠随机分为3组行鼓膜紧张部穿孔，前2组各10只分别为圆形或肾形穿孔，左耳用CO2激光，右耳用鼓膜切开刀，比较穿孔愈合时间，并观察鼓膜穿孔愈合过程的组织学变化，第3组5只用不同功率的CO2激光，左耳直接照射，右耳鼓室内注射生理盐水后再照射。结果：CO2激光组穿孔愈合时间较鼓膜切开刀组明显延长（P〈0．01）；肾形穿孔愈合时间更长（P〈0．01）。CO2激光组穿孔边缘出现炎症反应。小剂量激光对内耳无影响，鼓室内注水可以避免或减轻对耳蜗的损伤。结论：CO2激光鼓膜切开术可用于治疗分泌性中耳炎。

Experimental study of CO2 laser myringotomy

Objective: To study the therapeutic efficacy of carbon dioxide(CO_2) laser myringotomy and the following histopathological changes of tympanic membranes.Methods: Twenty-five guinea pigs were randomly divided into 3 groups: group 1(n=10),group 2(n=10),and group 3(n=5).In groups 1 and 2,CO_2 laser round and kidney-shaped myringotomy were performed on the left ears,respectively,and incisional round and kidney-shaped myringotomy were performed on the right ears,respectively.The healing time was compared,and the histopathological changes were observed.In group 3,CO_2 laser of different powers were performed on the left ears directly and on the right ears after saline was injected into the middle ear cavity.Results: The healing time in CO_2 laser myringotomy group was significantly longer than that in incisional myringotomy group(P<0.01).The healing time in CO_2 laser kidney-shaped myringotomy group was longer than that in CO_2 laser round myringotomy group(P<0.01).Inflammation was found in the CO_2 laser myringotomy group.The low power of CO_2 laser had no effect on the inner ear.Injecting saline into the middle ear cavity could avoid or alleviate the cochlear impairment.Conclusion: CO_2 laser myringotomy can be used in the treatment of secretory otitis media.