Healing modulation in glaucoma surgery after application of subconjunctival triamcinolone acetate alone or combined with mitomycin C: an experimetal study

ABSTRACT Objective: to study the efficacy and safety of the use of subconjunctival triamcinolone acetate alone or in combination with mitomycin C as a modulator of trabeculectomy healing in rabbits. Methods: we submitted thirty male, albino, New Zealand rabbits to bilateral trabeculectomy. We divided the animals into four experimental groups with 15 eyes per group: control, mitomycin C, triamcinolone acetate and triamcinolone acetate + mitomycin C. We performed aplanation tonometry and clinical analysis of the bleb through the Moorfields Graduation System in the postoperative period. For the evaluation of healing, we carried out the quantitative analysis of the inflammatory infiltrate (polymorphonuclear) through Hematoxylin & Eosin staining, and vascular proliferation, through immunohistochemistry. Results: we observed a significant decrease in postoperative intraocular pressure in all groups compared with the preoperative pressure (p<0.001). However, there was no difference between groups (p=0.186). The triamcinolone + mitomycin C acetate group presented better indices as for the maximum bleb height and vascularization of the bleb central area (p=0.001); in addition, there was a lower inflammatory response (p=0.001) and lower vascular proliferation (p=0.001) in the intermediate phase of the study compared with the monotherapies. Conclusion: the combination of mitomycin C and triamcinolone acetate resulted in a synergistic action between these agents, with broader and more diffuse blebs, less inflammatory infiltrate and less vascular proliferation in the intermediate stages of follow-up in this animal model.

摘要
目的：研究单用结膜下注射醋酸曲安奈德（triamcinolone acetate），或联合丝裂霉素C（mitomycin C）作为兔小梁切除术（trabeculectomy）愈合调节剂的疗效与安全性。
方法：将30只雄性白化新西兰兔行双侧小梁切除术，将实验动物分为4个实验组，每组15只眼：对照组、丝裂霉素C组、醋酸曲安奈德组，以及醋酸曲安奈德联合丝裂霉素C组。术后采用穆尔菲尔德斯分度系统（Moorfields Graduation System）进行压平眼压测量及滤过泡临床分析。为评估愈合情况，通过苏木精-伊红（Hematoxylin & Eosin）染色对炎性浸润（多形核白细胞）进行定量分析，并通过免疫组织化学法检测血管增殖情况。
结果：与术前眼压相比，所有组术后眼压均显著降低（p<0.001），但各组间差异无统计学意义（p=0.186）。醋酸曲安奈德联合丝裂霉素C组在最大滤过泡高度及滤过泡中央区血管化程度方面表现更优（p=0.001）；此外，与单药治疗组相比，该组在研究中期的炎症反应更轻（p=0.001），血管增殖程度更低（p=0.001）。
结论：在本动物模型中，丝裂霉素C与醋酸曲安奈德联合使用可产生协同作用，随访中期可见滤过泡更宽大弥散、炎性浸润更少、血管增殖程度更低。