Femtosecond Laser Liquid Optics Interface as Low Vision Optical Resource.

PURPOSE: To assess the efficacy of a low-cost optical magnifier created from the repurposed femtosecond laser interface used in cataract surgery to reduce healthcare waste and financial burden for low-vision patients.

METHODS

This prospective study included 16 Brazilian patients from the Low Vision Department of the Irmandade da Santa Casa de Misericórdia de São Paulo. Participants had visual acuity between +0.5 and +1.3 logMAR and visual field constrictions under 20°. The Catalys® femtosecond laser interface lens, usually discarded after surgery, was sterilized and attached to a recyclable support to create a magnifying device. Patients were trained to use it for 30 days. Visual function was assessed with the NEI VFQ-25, and reading performance was measured using the MNREAD-P test.

RESULTS

Thirteen patients (81.25%) completed the study. The use of the optical device led to significant improvements in all MNREAD-P parameters. Reading acuity improved from 0.74 ± 0.19 logMAR (20/110 Snellen) to 0.41 ± 0.22 logMAR (20/50 Snellen) (p < 0.001). Critical print size decreased from 0.85 ± 0.19 logMAR (20/140 Snellen) to 0.56 ± 0.24 logMAR (20/70 Snellen) (p < 0.001). Maximum reading speed increased from 41.4 ± 18.0 words per minute (wpm) to 56.2 ± 25.2 wpm (p < 0.001). NEI VFQ-25 scores improved from 32.7 ± 13.8 to 46.9 ± 15.0 (p < 0.001), with increases observed in all subcategories, particularly in "Reactions to Vision Problems."

CONCLUSION

Repurposing the femtosecond laser interface lens as a low-cost magnifier showed promising improvements in reading and visual function for low-vision patients while addressing healthcare waste. Further studies with larger samples are recommended to validate and expand this sustainable approach in visual rehabilitation.