Expression and distribution of extracellular matrices during corneal wound healing after keratomileusis

Purpose. To investigate the wound healing response following keratomileusis in situ in rabbits. Methods. Using immunofluorescence techniques, we studied the time course of the appearance and distribution of fibronectin, fibrin, and collagen type III at follow-up intervals from 1 hour to 3 months after keratomileusis in situ. Results. Three hours after induced injury, fibronectin and fibrin began to deposit from the periphery of denuded stromal surface, and formed continuous layer by 6 hours, progressively diminishing thereafter. Once the wound was reepithelialized, both fibronectin and fibrin disappeared. For keratomileusis in situ, collagen type III was detected only in the periphery of the cap-bed interface, where the collagen lamellae were cut in cross-section. The most striking finding was that in the central zone of the cap-bed interface where the cap was resected in parallel with the stromal collagen lamella, collagen type III was not detected. Conclusions After keratomileusis in situ in rabbits, fibronectin and fibrin play an important role in epithelial healing. By 7 days, collagen type III takes part in stromal healing, which probably takes place in the periphery. No deposition of this new collagen in the center of cap-bed interface may explain why optical clarity persists after keratomileusis in situ.