Effect of antioxidants in the rabbit cornea after photorefractive keratectomy
Fang Chengbo, Chen Ti, Yang Yongjian et al (Dept of Ophthalmology, The 1st Affiliated Hospital of Anhui Medical University,Hefei 230022)
Objective To investigate the effect of topical antioxidants vitamin C, vitamin E on cornea tissue after photorefractive keratectomy. Methods 24 experimental rabbits were divided into 2 groups,each consisting of 12 animals. They were undergone bilateral PRK to correct 5 diopters of myopia. Following the trea tment, the left eye of each rabbit in one group was given subconjunctival injec tion with vitamin C 0 1 every day. The right eyes served as controls. In the ot her group the left eyes of each rabbit was given subconjunctival injection with vitamin E 25 mg every day. The right eyes served as controls. Rabbits were kille d at 1,3,7 and 14 days respectively,then measured the activity of corneal supero xide dismutase(SOD) and glutathioneperoxide(GSH PX), the level of corneal malon dialdehyde(MDA), and observed histopathological changes in cornea. Resul ts We found significant decrease in SOD, GSH PX activity( P 0 01) and increase in MDA level( P 0 01) compared with the control following 1,3 days after PRK. But the corneal S OD, GSH PX activity in antioxidants group was significantly higher than that of PRK group. The level of MDA in of antioxidants group was significantly lower th an that of PRK group. Conclusion Free oxygen radical causes tiss ue damage in the cornea after PRK. Topical vitamin C or vitamin E application de creases oxygen radical tissue damage after excimer laser corneal surgery.