Aloe Vera Gel-derived Eye Drops for Alkaline Corneal Injury in a Rabbit Model
Purpose: To investigate the efficacy of topical Aloe Vera (AV) gel-derived eye drops on the healing of alkali-burned corneas in rabbits.
Methods: Thirty alkali-burned corneas of 30 New Zealand albino rabbits were categorized into three groups: AV treatment group that received AV gel-derived eye drops four times a day; medical therapy (MT) group that received conventional treatment; and the control group. Clinical examinations together with digital imaging of the corneas were performed on days 0, 1, 2, 4, and 7. The area of the corneal epithelial defect (CED) was measured using ImageJ software. After euthanizing the rabbits, the affected corneas were evaluated by histopathological examination. Finally, the clinical and histopathological results were compared among the groups.
Results: The CED area on days 2 and 7 was significantly less in the AV group than that in the MT group (P = 0.007 and P = 0.024, respectively) and the control group (P = 0.003 and P = 0.037, respectively). None of the cases developed hypersensitivity reactions, limbal ischemia, descemetocele, or corneal perforation during the study period. Based on histopathology, the AV group had notably less keratocyte loss than the MT group (P = 0.001) and the control group (P = 0.022). The inflammatory response after the alkali burn was higher in the AV group than that in the controls (P = 0.028).
Conclusion: Short-term topical AV treatment was effective in healing alkali-burned corneas and hastened corneal re-epithelialization as compared to MT; however, AV gel-derived eye drops did not reduce the inflammatory response.
Alkali Burn, Aloe Vera, Epithelialization, Rabbits
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