A comparison of the effect of hyaluronic acid versus gentamicin on corneal epithelial healing

Purpose An animal model study was conducted to compare the efficacy of recurrent topical applications of hyaluronic acid and gentamicin ointment for the treatment of noninfected, mechanical corneal erosions. Methods An artificial, controlled wound of identical size and depth was inflicted to the corneas of three groups of rabbit eyes in order to measure their healing rates. One group was treated with hyaluronic acid (10 eyes) while the second group received gentamicin ointment (10 eyes). The third group remained untreated and served as the control (10 eyes). The rate of re-epithelisation was measured at 8-h intervals until complete re-epithelisation was observed. After complete wound closure, the rabbits were killed, and comparative histological examinations were performed. Results Rabbit eyes treated with hyaluronic acid showed a significantly enhanced rate of epithelial defect closure compared with untreated eyes and a similar rate to that achieved with gentamicin ointment. In the eyes treated with hyaluronic acid a normal, multilayered epithelium was observed 48 h after complete healing, whereas the gentamicin-treated eyes showed an imperfectly layered epithelium, with irregularity of the cuboidal cells. Conclusion While both hyaluronic acid and gentamicin enhance corneal epithelial healing at comparable rates, our study suggests that hyaluronic acid may have a more favourable effect on the structure of the healing epithelium, and can offer an alternative mode of therapy for non-infectious corneal erosions.