The Study on Healing of the Corneal Epithelial Cells in Laser Assisted Subepithelial Keratectomy (LASEK) on Rabbits

Kim, Myung Jin; Kim, Sang Kyun; Oh, Jung Hyub

Abstract

PURPOSE
To investigate the difference in healing of the corneal epithelial cells between in LASEK and in PRK and the factor to induce the difference. METHODS: The rate of corneal epithelial recovery was measured after mechanical removal of corneal epithelium (PRK) or after removal with alcohol (LASEK) in rabbits. PCNA (proliferating cell nuclear antigen) staining was performed to compare the degree of cellular proliferation. Immunocytochemical staining was also carried out to examine the expressions of fibronectin and EGFR (epidermal growth factor receptor), which were known as the factors participating in corneal epithelial regeneration. In cultured porcine corneal epithelial cells, the degree of epithelial proliferation was compared between the control group (group I without alcohol treatment) and alcohol treated groups with various alcohol concentrations (groups II, III, IV and V) after cell culture for 2 weeks. RESULTS: The rate of epithelial healing was faster in LASEK group than in PRK group. These epithelial cells recovered to normal cells faster in LASEK group than in PRK group according to light and electron microscopic findings. PCNA expression and fibronectin expression were higher in LASEK group than in PRK group, whereas no difference was seen in the expression of EGFR. Although the proliferation of corneal epithelial cells increased, it was not proportional to the amount of added alcohol-treated epithelial cells. CONCLUSIONS: We showed that the corneal epithelia recovered to normal shape faster in LASEK than in PRK group when alcohol treated corneal epithelial cells were treated to the site of the wound. Higher expression of fibronectin in LASEK group suggest that fibronectin could be a factor promoting corneal epithelial cell regeneration.