Abstract: Objective To develop an experimental animal model of neovascularization 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 enucleated and histopathologically studied. Results A rise of IOP in the immediate postoperative period was noticed, then decreased gradually, finally ended with a low IOP. On slit lamp examination, neovascularization 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.

Key words: anterior ischemia, neovascularization of iris, animal model