Avastin抑制兔眼小梁切除术后滤过泡瘢痕化的作用

Study of treating the bleb fibrosis after trabeculectomy with Avastin

目的:探讨Avastin抑制兔眼小梁切除术后滤过泡纤维瘢痕形成的作用。方法:兔20只40眼随机分为3个不同剂量Avastin实验组、丝裂霉素C(MMC)对照组及空白对照组。对兔眼行常规小梁切除术,Avastin实验组于术毕及术后3,7d术区结膜下分别注射0.5,1及2mg Avastin;MMC对照组术中筋膜囊、巩膜瓣下放置0.2g/LMMC棉片。术后裂隙灯下观察滤过泡形态及角膜、前房等情况;术后7,14d摘除眼球,常规HE染色观察组织形态,在高倍视野中,通过滤过泡腔面在结膜中形成的面积百分比及滤过泡形成区在结膜中面积百分比,评价不同剂量Avastin结膜下注射对滤过泡形成及纤维化的影响。结果:术后7d各组结膜纤维结缔组织中均可见明显的滤过泡形成。术后14d仅注射2mg Avastin实验组及MMC对照组的结膜组织中可见明显滤过泡;1mg Avastin实验组见少量面积微小的滤过泡;0.5mg Avastin实验组及空白对照组滤过泡均消失,纤维组织增生明显。术后7d各组高倍视野下滤过泡腔面在结膜中形成的面积百分比及滤过泡形成区在结膜中面积百分比无明显差异。术后14d,2mg及1mg Avastin实验组滤过泡腔面积在结膜中形成的面积百分比分别为1.0%,0.8%,MMC组为0.9%。2mg及1mgAvastin实验组滤过泡形成区在结膜中面积百分比分别为26.1%,2.9%,MMC组为25.8%。2mg及1mgAvastin实验组的滤过泡腔面及形成区面积与结膜面积的百分比均明显高于空白对照组,单项方差分析结果分别为F=270.10,P=0.00;F=49.99,P=0.00;2mg Avastin实验组的上述滤过泡面积百分比与MMC组无差异。结论:结膜下注射Avastin可有效帮助滤过术后滤过泡的形成与维持,缓解滤过泡的纤维增生。

AIM： To evaluate the efficacy of Avastin on treating the bleb fibrosis after trabeculectomy in rabbits. METHODS： Forty eyes of 20 rabbits undergone trabeculectomy were randomly divided into three different doses of Avastin experimental groups, mitomycin C （MMC） group and blank control group. The eyes in three Avastin experimental groups were randomly received subconjunctival injection of 0. 5, 1,2mg Avastin when trabeculectomy finished and on 3^rd,7^th days after surgery. In the MMC treated group, MMC cotton patch, 0. 2g/L, was put under the capsule Tenons and scleral flap during operation. The appearance of filtrating bleb and inflammatory reactions were observed under slit-lamp; the filter areas were taken histopathologic examination on postoperative 7,14 days. RESULTS： Filter blebs could be seen clearly in each group on postoperative 7 days. And on postoperative 14 days in the 2mg Avastin group and MMC group, filtering blebs were larger and more elevated than other groups; in ling Avastin group, there were only some small blebs; and in 0. 5mg Avastin group and blank control group, filter blebs disappeared, and marked hyperplasia of fibrous tissue could be seen. Under the microscope on postoperative 7 days, there was no significant difference in the percentage of the bleb cavity surface area in the conjunctiva and the percentage of bleb-forming region in the conjunctiva. On postoperative 14 days, the percentage of the bleb cavity surface area in the conjunctiva of 2 mg and lmg Avastin groups and MMC group were respectively 1.0%, 0, 8%, 0.9% ; and the percentage of bleb-forming region in the conjunctiva were 26.1%, 2.9%, 25.8%. The percentage of the bleb cavity surface area in the conjunctiva and the percentage of bleb-forming region in the conjunctiva of 2mg and 1 mg Avastin group were significantly higher than the blank control group, respectively（P = 0. 00; P = 0. 00）. But there was no significantly difference between 2mg Avastin group and MMC group on the filtering bleb area percentage. CONCLUSION. Subconjunctival injection of Avastin can effectively prevent the bleb fibrosis, maintain larger bleb area. This indicates that Avastin is most likely to be a novel agent to prevent excessive scarring following trabeculectomy.