The inhibition effect of subconjunctival Bevacizumab on rabbit corneal neovascularization

Abstract

Objective To evaluate the effect of subconjunctival bevacizumab on experimental corneal neovascularization (NV) in rabbits at different time points.Methods The right eyes of 54 white New Zealand rabbits were chemically burned with 1mol/L NaOH and randomly divided into three groups.Eighteen eyes (group A) received subconjunctival injection of bevacizumab (2.5 mg,0.1 mL) immediately after burn.Eighteen eyes (group B) received subconjunctival injection of bevacizumab (2.5 mg,0.1 mL) 3 days after burn with subconjunctival injection of normal saline.Group C was the control group.The angiogenesis and inhibition of corneal neovascularization were detected respectively by measuring the length and area of NV under slit lamp microscopy everyday.Corneal confocal microscope was used to detect the cornea at 7 days,14 days and 28 days after corneal burn.Results The occurrence time of corneal NV was (5.9± 0.8) d,(3.5 ± 0.6) d and (3.4 ± 1.1) d in group A,B and C.Compared with the group C,the corneal NV occurrence was significantly delayed in group A and B.No significant difference in the occurrence time of corneal NV was found between group B and group C (P =0.068).The corneal NV areas of group A and group B were smaller than the group C at different time points,and the difference has statistical significance (P ＜ 0.05).The degrees of fibrous structures and scars in corneal stroma of treatment groups were slightly less than the group C.Conclusion Subconjunctival injection of bevacizumab can sufficiently decrease the number of inflammatory cells in the cornea after chemical burn,improve the microenvironment of injured corneal stroma and accelerate the cornea wound healing,which eventually inhibit the growth of corneal NV.The anti-neovascular effect of bevacizumab is better if the injection is performed at the early stage of corneal angiogenesis. Key words: Bevacizumab; Neovascularization; chemical burn ; Microscope, confocal, corneal