Ocular surface restoration and corneal nerve regeneration following treatment with autologous serum eye drops in patients with Paralytic Lagophthalmos and Neurotrophic Keratitis

Purpose: To evaluate the effect of 20% autologous serum eye drops (ASED) treatment on enhancing ocular surface health and promoting corneal nerve regeneration in individuals affected by Paralytic Lagophthalmos (PL) and Neurotrophic Keratitis (NK). This prospective study included 11 patients with unilateral NK and PL treated with 20% ASED for 2 months. Baseline ocular surface assessments included Schirmer I test; non-invasive tear film break up time (NIBUT) using a corneal Sirius topographer (CSO, Florence, Italy); Cochet-Bonnet esthesiometry; slit-lamp examination with fluorescein staining graded using the modified Oxford Grading System; in vivo confocal microscopy (IVCM) for corneal nerve fiber length (CNFL), nerve fiber density (CNFD), and nerve branch density (CNBD). The same measurements were repeated at the end of the treatment period (60 days ±2 days). Results Ten patients completed the study. One patient discontinued treatment due to ocular discomfort. ASED treatment significantly improved Schirmer I values (mean: 10.3 ± 4.7 mm to 19.7 ± 12.1 mm; p=0.041), OSDI scores (21.1 ± 12.9 to 17.0 ± 10.0; p=0.009), and corneal sensitivity readings (central esthesiometry: 3.4 ± 1.9 mm to 5.0 ± 1.2 mm; p =0.005). IVCM revealed significant increases in CNFL (11.1 ± 6.4 to 14.7 ± 7.3 mm/mm2; p=0.006) and CNFD (23.1 ± 13.2 to 33.8 ± 11.9 fibers/mm2; p=0.012). Conclusion In conclusion, this study highlights the potential of 20% ASED to promote corneal nerve regeneration, enhance corneal sensitivity, and restore ocular surface health in patients with PL and NK. These findings support the neurotrophic and regenerative properties of ASED as a promising therapeutic option for complex ocular surface diseases with IVCM as a valuable tool for monitoring nerve recovery. Larger, long-term studies are warranted to confirm these results and optimize treatment protocols.