The Relationship between Immunohistochemical Expression of c-fos and Histopathologic Changes after Excimer Laser Photorefractive Keratectomy

Hong, Jong Wook; Kim, Hyo Myung; Huh, Kuhl; Lee, Tae Soo

Abstract

Excimer laser photorefractive keratectomy(PRK) in high myopia frequently cause corneal opacity and myopic regression. In cases of corneal opacity, corneal histopathologic changes were developed and cellular damages were occured. To find the relationship between histologic changes and expression of c-fos, the author studied on the histologic findings for corneal epithelial thickness, stromal PMN cells, and keratocytes and immnunohistochemical stain for c-fos after myopic excimer laser PRK. Thirty Newzealand white rabbits(60 eyes) were divided into four groups : -6D, -9D, -15D, and control group. Myopic excimer laser PRK was carried out on the cornea to correct the amounts of -6D, -9D, and -15D myopia with Excimer laser (VisX 20/20, Sunnyvale, USA). The corneal status was examined using a slit lamp. The eyes were enucleated at 6, 24, 48 hours, 1 week and 8 weeks after operation. The corneas were obtained and sectioned for H-E and immunohistochemical stains. Corneal opacity was found with the mean density of 0.83(-6D group), 1 (-9D group), and 1.67(-15D group) 8 weeks after the operation. Corneal epithelial thickness and stromal keratocytes were increased in -15D group more than in the remaining two groups(p<0.05). c-fos was detected in corneal epithelium at 6 hours after operation in -6D, -9D, and -15D group. But maximal expression was found at 24 hours after operation in -15D group. Consquently, the author believes that expression of c-fos and stromal keratocyte changes might be a important role of corneal haziness following PRK.