evaluation of topical phenytoin eye drop 1% therapeutic effects on corneal alkali burns in rabbit model

purpose : studies show that phenytoin is effective in improvement of different chronic ulcers such as venous stasis ulcers, and diabetic ulcers. the exact mechanism is yet not clear investigators thought that phenytoin might help to heal intractable corneal ulcers by reducing inflammation, differentiating limbal fibroblasts, and promoting the invasion of the cornea with new blood vessels as shown in animal and in vitro studies. given the importance of healing process of corneal alkali burns which are common and always problematic, the need for finding strategies that can help improve this process is always felt. this study investigated the effect of topical phenytoin 1% in corneal epithelial defects healing in rabbit model. methods : a chemical corneal epithelial defect was created in one eye of albino rabbits in animal house of al-zahra eye center. rabbits were randomly assigned into two groups of ten. the case group was treated using soluble phenytoin 1% eye drop and the control group received normal saline eye drop. clinical assessment and epithelial defect size were evaluated daily for 14 days using slit-lamp biomicroscopy. data were analyzed using independent t-test and anova on repeated observations. results : the difference between the first and the last day of follow-up in each group was significant (p<0.05). topical phenytoin 1% induced a significantly faster epithelial healing in comparison with the control group (p<0.05). conclusion : topical phenytoin 1% can help in improvement of epithelial defect caused by alkali burns as a supplement treatment.      iranian journal of ophthalmology 201224(3):33-38 © 2012 by the iranian society of ophthalmology