Experimental Study Of The Comparison Of Avastin's Two Different Treatment Methods To Early Proliferation Of Corneal Neovascularization After Alkali Burn

Objective:To investigate Avastin eyedrops and subconjunctival Avastin on corneal neovascularization(CNV)induced by corneal alkali burns(CAB)in SD rats.The purpose of the study is to find an effective and convenient new method to prevent and treat CNV.Methods:1.Experimental subgroup:Single eye corneal alkali burn model was established in 75 male majority Sprague dawley.All rats were divided into 3 groups randomly,each group including 25.Group A(control group)was treated by 3g/l FPA,twice a day,continuing medication 2 weeks;group B(Avastin eyedrops group)was treated by 4mg/ml Avastin and 3g/l FPA,twice a day,for 2 weeks;and group C was treated by subconjunctival Avastin on the second and the sixth day after corneal alkali burn,with 3g/l FPA twice a day,for 2 weeks.2.Experimental observation:the occurrence and development of CNV were observed termly by slit lamp microscope on the 3th,5th,7th,14th day after corneal alkali burn,and the area of CNV was calculated by using computer image analysis.Then five rats of each group were killed on the 3th,5th,7th,14th day after corneal alkali burn,and the corneal were taken for histopathological examinations to detect VEGFR-2,and immunofluorescence examinations to detect CD31,and to detect the state and quantity of CNV of A group by electron microscope.Results:1.The corneal neovascularization areas of group B,C was smaller than group A(P<0.01)with no significant difference between B andC in terms of CNV areas(P>0.01).2.The level of VEGFR-2 and CD31 expression in group B,C was lower than group A(P<0.01)with no significant difference between B and C(P>0.01).3.Tansmission electron microscope for corneal:There were endothelial cell and inconsecutive tubiform structure in corneal substantia propria layer on the 3th day. Typical neovascularization structure and blood cells can be found on the 5th day.The newly tubiforms augment,and the amount of blood cells increases on the 7th day.Then the amount decreases on the 14th day,and at the same time cytomorphosis occurs.Conclusions:Avastin eyedrops(4mg/ml)and subconjunctival Avastin(1.25mg)both can effectively inhibition CNV after alkali burns.No significant difference was found between the two groups.