Corneal Neurotization: A Review of Pathophysiology and Outcomes

The objective of this study is to provide a systematic review of the clinical outcomes of corneal neurotization and present the pathophysiology of corneal wound healing, neurotrophic keratopathy, and corneal neurotization.

A literature review of published articles and meeting abstracts between December 2008 and February 2019 in the English language with the terms "corneal neurotization," "corneal neurotisation," "corneal reinnervation," and "neurotrophic keratopathy" was performed. Reported clinical data before and after corneal neurotization, and surgical techniques, were collected and analyzed.

A total of 54 eyes that underwent corneal neurotization were identified. Final Logarithm of the Minimum Angle of Resolution (logMAR) best-corrected visual acuity improved to 0.85 (standard deviation [SD] = 0.65) from 1.25 (SD = 0.71) with a mean improvement of 0.41 (SD = 0.55; p < 0.0001). Central corneal sensation measured using Cochet-Bonnet esthesiometer improved from 2.18 mm (SD = 0.4) to 40.10 mm (SD = 18.66) with a mean filament length change of 38.00 mm (SD = 18.95; p < 0.0001). The median time to the reported maximal sensation return was 8 months (interquartile range 6-10). The most common reported limitation to visual recovery was corneal scarring (31.5%). Children (ages 0-17 years) as compared with adults (ages 18-82 years) had significantly greater final central corneal sensation esthesiometry readings, central corneal sensation return, and improvement in the logMAR best-corrected visual acuity (p < 0.011).

Neurotrophic keratopathy disturbs the homeostatic balance of trophic factors and trigeminal nerve reflexes needed to support ocular surface health and corneal healing. Corneal neurotization can significantly improve corneal sensation and visual acuity and should be considered for the treatment of refractory neurotrophic keratopathy, especially in pediatric populations.