Abstract
Purpose: :
To evaluate the effect of topically administered fludrocortisone acetate and triamcinolone acetonide on experimental corneal neovascularization in rats.
Methods: :
Six groups of eight eyes belonging to male Long Evans rats were evaluated in this study. All procedures were performed under general anesthesia. After applying 0.5 % proparacaine hydrochloride as a topical anesthetic agent, the corneas of all 48 eyes were chemically cauterized using silver nitrate on an applicator stick. After corneal cauterization, the eyes received one drop twice per day of fludrocortisone, triamcinolone acetonide, or normal saline. The first three groups received fludrocortisone acetate drops in three different concentrations, 4 mg/ml, 10 µg/ml, and 5 µg/ml. The next two groups received triamcinolone acetonide drops in two different concentrations, 10 µg/ml and 5 µg/ml. The remaining group received normal saline drops as a control. All corneas were evaluated with digital photography. The percentage of area of corneal neovascularization and scar formation was determined with the aid of computer software. After seven days, all animals were sacrificed and the corneal tissue was evaluated histopathologically.
Results: :
The mean percent areas of corneal neovascularization in the fludrocortisone group at 4 mg/ml, 10 µg/ml, 5 µg/ml and the control group were 3.37 ± 9.54 (p=0.001), 26.37 ± 19.2 (p=0.001), 35.37 ± 27.4 (p=0.05 0) and 65.37 ± 3.7, respectively. The mean percent area of corneal neovascularization in the triamcinolone group at 10 µg/ml and 5 µg/ml was 53 ± 14 (p=0.04) and 54.1 ± 11.58 (p=0.05), respectively. The mean percent areas of corneal neovascularization in the triamcinolone groups at 4 mg/ml, 10 µg/ml, 5 µg/ml, and 10 µg/ml were significantly lower than the control group. In the 5 µg/ml triamcinolone group, the results were insignificant with a p value of >0.05. Histology was consistent with our results.
Conclusions: :
Topically administered fludrocortisone acetate and triamcinolone acetonide demonstrate antiangiogenic properties in the rat model of corneal neovascularization. Fludrocortisone appears to be the more effective agent in this study. Topically applied triamcinolone acetonide does not appear to have antiangiogenic properties in concentrations below 10 µg/ml. However, at higher concentrations, triamcinolone acetonide showed inhibition of neovascularization.
Keywords: cornea: epithelium • corticosteroids • neovascularization