Efficacy of Insulin Eye Drops in the Treatment of Corneal Ulcers in Patients with Facial Nerve Palsy and Lagophthalmos: A Retrospective Case-Control Study.

Background and Objectives: Corneal ulcers in patients with lagophthalmos due to facial nerve palsy pose a significant therapeutic challenge. Topical insulin has emerged as a promising adjuvant therapy for enhancing corneal re-epithelialization. The aim of this study is to evaluate the efficacy of insulin drops compared with lipid-based artificial tears, and to compare the corneal healing rate in achieving complete epithelialization within 30 days in diabetic patients. Materials and Methods: This retrospective case-control study included 32 patients with facial nerve palsy and lagophthalmos who developed an exposed corneal ulcer, of whom 20 received topical insulin and 12 received lipid-based artificial tears. The primary outcome was complete epithelialization at day 30. Additional variables included age, sex, and baseline defect characteristics. Results: By day 30, complete epithelialization was achieved in 18 of 20 patients (90%) in the insulin group compared with 5 of 12 (41.7%) in the control group. Binary logistic regression analysis confirmed significantly higher odds of healing with insulin treatment (OR = 10.8; 95% CI 1.8-63.9). No systemic adverse events or signs of hypoglycemia were observed. Conclusions: Topical insulin significantly accelerates corneal epithelialization in patients with facial nerve palsy and exposed ulcers, offering safe and effective adjuvant therapy for a high-risk population. Despite promising results, the study's limitations-including small sample size, single-center design, and retrospective nature-highlight the need for larger, multicenter prospective studies to confirm efficacy, optimize dosing, and further evaluate long-term safety.