Topical Insulin Versus Autologous Serum and Enhanced Corneal Epithelial Healing After Keratorefractive Surgeries

Topical insulin has been proved recently to enhance the corneal reepithelization rate and manage neurotrophic corneal ulcers unresponsive to conventional treatments. However, its effectiveness on corneal epithelial wound healing in patients who received photorefractive keratectomy (PRK) has not been reported. In this study, we plan to perform a prospective non-randomized study to determine the efficacy and safety of topical insulin as a primary treatment for a corneal epithelial defect in patients undergoing the PRK and compare that to autologous serum eye drops. The study eye will receive either the insulin or the serum eye drops, in addition to the conventional treatment, while the control eye will have the standard treatment. For each eligible candidate, the eye with a higher depth of ablation will be the study eye. If even ablation depth in both eyes, the right eye will be selected. The conventional postoperative eye drops include topical moxifloxacin 0.5% (Vigamox; Alcon Laboratories) four times per day, artificial tears (Systane Ultra; Alcon) every two hours, Dexamethasone 0.1% (Maxidex; Alcon Laboratories) four times daily for one month followed by fluorometholone 0.1% (Efemyo; OrchidiaLaboratories) four times daily for another two to four weeks depending on refraction and haze level. In study eyes, the patients receive either topical insulin eye drops or autologous serum in addition to conventional postoperative eye drops until complete epithelial healing. The duration for the corneal surface to completely re-epithelize, the grade of postoperative corneal haze, the incidence of corneal complications due to delayed surface re-epithelization (e.g. infectious corneal ulcer, corneal melting, sterile corneal ulcer, corneal neovascularization), and the distant corrected visual acuity will be compared between these three groups.