兔眼高眼压模型行CO_2激光滤过术的研究

目的探讨应用CO2激光对兔眼高眼压模型行滤过性手术的可行性和有效性。方法日本大耳白兔20只40只眼后房注入1000U/mL（商品单位）α-糜蛋白酶0.15～0.20mL提高眼压至25mmHg或眼压增幅达8mmHg制备高眼压模型。造模成功后,右眼应用超脉冲CO2激光行巩膜瓣下巩膜床扫射及小梁切除术为激光组;左眼行传统小梁切除术为手术组。激光扫射参数：功率1～2W,脉宽0.1ms,频率100Hz。小梁及虹膜根部切除孔（直径800μm）的激光参数为：功率4～5W,脉宽0.8ms,频率100Hz。比较2组兔眼术后不同时间的前房反应、滤过泡情况、眼压、组织病理学变化。结果激光组术后前房反应轻微,手术组较重。术后3d时激光组功能性滤过泡为20眼,手术组19眼;术后30d时手术组功能性滤过泡比例下降明显,2组间差异有统计学意义（P〈0.05）。2组术后眼压均逐渐升高,手术组较激光组眼压升高较早,术后第14、30、60天2组眼压差异均有统计学意义（P〈0.05）。组织病理学显示,2组早期滤过道均通畅,但手术组出血和炎性渗出明显,激光组较手术组增生反应出现晚,且程度轻。结论应用超脉冲CO2激光在兔高眼压模型眼进行小梁切除术安全可行,降眼压效果稳定持久。

CO2 laser-assisted filtering surgery in rabbits intraocular hypertension model

Background Although the conventional anti-glaucoma surgery can reduce intraocular pressure（IOP） to some extent,some postoperative complications such as hyphema,shallow anterior chamber and low IOP often occur at early stage,and fibrous scar formation on filtration tract also appeared at the late stage after operation.Objective The aim of this study was to investigate the feasibility and validity of CO2 laser-assisted filtering surgery to treat intraocular hypertension model.Methods The ocular hypertension models were included by the posterior chamber injection of α-chymotrypsin in bilateral eyes of 20 adult Japanese white rabbits.The ultrapulse CO2 laser-assisted filtering surgery was performed in the right eyes of rabbits and the conventional filtering surgery was taken in the left eyes.In laser group,CO2 laser was emitted on the scleral flap beneath scleral bed to perform the trabeculectomy with the average power 1-2 W,pulse width 0.1 ms,frequency 100 Hz,and meanwhile iris radical excision was executed with the average power 4-5 W,pulse width 0.8 ms at the frequency of 100 Hz.The gradation of anterior chamber reaction and type of filtering bleb were assessed under the slim lamp,and intraocular pressure （IOP） was measured using Perkins applanation tonometer.The pathological examination of eyeballs was curried out in different time points after operation.Results Anterior chamber reaction was more mild in laser group than conventional surgery group.A statistically significant difference was found in the numbers of eyes with anterior chamber response between two groups in 1,3,7 days after operation （P0.05）.Thirty-nine eyes in both groups appeared the functional filtering bleb in 3 days after operation,and the proportion of functional filtering bleb was decreased significantly in conventional operative group in 30 days after operation,showing a significant difference between these two groups （P0.05）.The IOP was gradually elevated in both groups with the prolong of postoperative time,especially in conventional operative group,presenting considerably differences between two groups from 14 days through 60 days after operation （P0.01）.Histopathology examination showed that the proliferation of fibroblasts was slight in laser group compared with conventional operative group in the third day after operation,and the filtering trace was open till 60 day in laser group,but in conventional operative group,the filtering trace was close.The bleeding and inflammatory exudates were obvious in conventional operative group in comparison with laser group.Conclusion Applying ultrapulse CO2 laser to performe the trabeculectomy in rabbits with intraocular hypertension model is safe and feasible.