Topical Insulin in the Treatment of Ocular Surface Disease: A Retrospective Cohort Study

PURPOSE: To assess the efficacy of topical insulin for the treatment of various ocular surface diseases. METHODS: A retrospective, multicenter cohort study was conducted at the university hospitals of Brussels and Ghent and included 57 eyes (45 patients) treated with topical insulin (1 IU/mL 4 times daily) for neurotrophic keratopathy (NK) (n = 31), dry eye disease (DED) (n = 9), graft-versus-host disease (GVHD) (n = 7), and various other ocular surface diseases (n = 10) between October 2023 and March 2025. Data from medical records and anterior segment photographs were analyzed. Primary outcome was treatment success; secondary outcomes included clinical evolution, symptoms, data on persistent epithelial defects (PED), vision, and adverse events. RESULTS: Treatment success was highest in NK eyes (83.9%) as compared to DED and GVHD eyes (44.4% and 14.3%, respectively), with a statistically significant difference between NK and GVHD (P = 0.028). Treatment success did not differ significantly between eyes with NK grade 1, 2, and 3 (83.3%, 72.7%, and 92.9%, respectively) (all P > 0.05). Twenty out of 28 (71.4%) PED eyes of various etiologies achieved complete closure after 5.2 weeks, whereas 6 eyes (21.4%) showed partial closure, and 2 eyes (7.1%) showed no improvement. One eye showed a significant transient IOP increase; no other adverse events were noted. CONCLUSIONS: These results suggest that topical insulin drops are a safe and affordable treatment option for ocular surface diseases, particularly for NK eyes with and without PED. Further prospective clinical trials, however, are needed to confirm the efficacy and define the place of topical insulin in standardized treatment protocols.