前节缺血致实验性兔虹膜新生血管模型

Experimental Neovascularization of Iris Induced by Anterior Ischemia in Rabbit

目的应用前节缺血的方法制备家兔实验性虹膜新生血管模型,观测其眼压波动、眼前节特别是虹膜组织病理学改变。方法对35只家兔的右眼行上、下直肌离断加涡静脉阻塞手术,用数字表法随机取30只家兔为第1组,从术前2d及术后每天测量眼压、裂隙灯观察至术后25d处死。眼球摘除后行HE和CD34免疫组化染色,光镜下观察。余5只家兔为第2组,从术前2d及术后每天行裂隙灯观察,至术后第9天处死,摘除眼球做组织学观察。左眼均作为对照仅测定眼压、裂隙灯观察及眼球摘除后光镜下观察。结果术后眼压呈先上升后下降趋势,最终稳定于低眼压水平。裂隙灯下虹膜新生血管于术后4～6d开始出现,术后9d时最明显,此后逐渐消退。HE和CD34染色显示2组家兔的实验眼均可见纤维血管增生膜堵塞房角,虹膜表面可见新生血管,术后25d组织学可见睫状体明显萎缩,术后9d睫状体以出血坏死为主,2组视网膜均未见明显异常。结论利用上、下直肌离断加涡静脉阻塞致前节缺血方法制作的实验性虹膜新生血管模型操作简单、廉价实用、虹膜新生血管出现率较高。

Objective To develop an experimental animal model of neovaseularization of iris （NVI）, using anterior segment ischemia, and investigate the changes of intraocular pressure （IOP） before and after surgery, as well as morphologic and histological changes of the anterior segment, especially the iris. Methods Recession of both vertical recti and occlusion of vortex veins in the right eyes of 35 rabbits, with the left eyes as control group. All eyes were examined by tonometry and slit lamp before surgery and thereafter during the follow-up period, 30 animals were sacrificed 25 days after surgery, 5 animals were killed 9 days after surgery. The eyes were enueleated and histopathologically studied. Results A rise of IOP in the immediate postoperative period was noticed, then decreased gradually, finally ended with a low lOP. On slit lamp examination, neovaseularization of the iris（NVI） appeared 4 -6 days after surgery, after 9 days, NVI began to regress until the follow-up period ended. Histologically, neovascularization on the anterior surface of iris was detected, and the iridocorneal angle were found obstructed by proliferative tissues with newly formed vessels after surgery. There was also necrosis and atrophy in the ciliary body, but no abnormal retinal changes were detected after surgery. Conclusion Experimental NVI induced by recession of both vertical recti and occlusion of vortex veins was a comparatively simple, inexpensive and reliable animal model.