Corneal Neurotization vs. Cenergermin for Neurotrophic Keratitis: A Pilot Study

Corneal Neurotization: A Study on the Outcomes of Nerve Repair for Corneal Sensory Dysfunction

This pilot study evaluates the feasibility and outcomes of two treatment approaches for corneal sensory dysfunction due to neurotrophic keratitis (NK): corneal neurotization surgery and topical Cenergermin (Oxervate). Participants will receive treatment based on clinical decision-making, not randomization, and will be followed for 12 months through eight visits at the Ivey Eye Institute, St. Joseph's Health Care London. Data collected during routine eye examinations and validated quality-of-life questionnaires will be used to assess visual outcomes, corneal structure and function, and patient-reported well-being. This feasibility study is funded by the Lawson Research Institute Internal Research Fund and is intended to generate preliminary evidence for a future randomized trial.

Neurotrophic keratitis (NK) is a rare, progressive condition characterized by impaired corneal sensation and reduced nerve function. It affects approximately 5 in 10,000 individuals worldwide and more than 6,000 Canadians annually. If untreated, NK can lead to corneal scarring, ulceration, and irreversible vision loss. Two existing treatments are currently in use: corneal neurotization, a surgical technique that transfers healthy donor nerves to the cornea and topical Cenergermin (Oxervate), a recombinant human nerve growth factor that promotes epithelial healing and nerve regeneration.

This single-center, prospective pilot study is designed to assess the feasibility of conducting a larger comparative trial between these two treatment approaches. Specifically, the study will determine whether it is clinically and logistically feasible to compare outcomes between patients undergoing neurotization surgery and those receiving Cenergermin drops as part of their standard care.

Ten adult participants (aged ≥19) with moderate to severe NK will be recruited from the Ivey Eye Institute at St. Joseph's Health Care London. Participants will receive either surgical or medical treatment based on standard clinical care decisions. No additional interventions will be introduced for research purposes.

Participants will be followed across eight time points: baseline (before treatment), 1 day, 1 week, 1 month, 3 months, 6 months, 9 months, and 12 months. Each visit will include routine clinical evaluations such as corneal sensitivity testing, corneal nerve imaging, slit lamp exams, intraocular pressure, visual acuity and contrast testing, and a brief quality-of-life questionnaire.

All data will be collected through standard, non-invasive assessments during regular clinical follow-up. There will be no masking; both participants and clinicians will be aware of the assigned treatment.

This research is part of a pilot grant funded by the Lawson Health Research Institute and will provide critical data to inform the development of a larger, fully powered randomized controlled trial.

Inclusion Criteria:

• Adults aged 19 years and older.
• Diagnosis of neurotrophic keratitis with reduced or absent corneal sensation.
• Clinical indication for either corneal neurotization surgery or topical Cenergermin treatment, as determined by the treating ophthalmologist.
• Ability to provide informed consent.

Exclusion Criteria:

• Active ocular infection or inflammation.
• Previous corneal neurotization procedure in the affected eye.
• Contraindications to general anesthesia or surgical intervention.
• Participation in another interventional clinical trial within the past 3 months.