Topical Insulin Treatment for Neurotrophic Corneal Ulcer with Persistent Epithelial Defect

Abstract

Background: Neurotrophic keratitis (NK) is a degenerative corneal disease caused by impairment of corneal sensory innervation. It is characterized by decreased or absent corneal sensation, leading to epithelial breakdown, impairment of healing, and ultimately to the development of corneal ulceration, melting, and perforation. We described a case of neurotrophic ulcer with persistent epithelial defect and its remarkable healing response to insulin eye drop treatment. Case Presentation: A 62-year-old male patient was referred to our hospital for the management of stage III NK in the left eye. The condition started 6 months ago; the patient developed a sudden onset of left eye diminution of vision, red eye, and tearing. The patient sought an ophthalmic consultation and was diagnosed with herpes simplex keratitis. On examination, visual acuity OS was hand motion (HM), severe conjunctival injection, deep corneal vascularization, corneal opacity with stromal infiltration, epithelial defect about 3.5 x 6 mm, stromal thinning, Descemet membrane folds and loss of corneal sensation by cotton wisp test. The patient was treated with topical insulin eye drops for 6 weeks and showed substantial ulcer healing and reepithelization of the epithelial defect. Conclusion: Insulin drops have been shown to substantially promote persistent epithelial defect healing in the case of neurotrophic ulcers. Therefore, topical insulin use can potentially help in the treatment of refractory neurotrophic keratitis. Further studies with large case numbers and long follow-ups should be the main focus of future research.