Ultraviolet-A Absorbance Analysis in Thin Porcine Corneas Pre-and Post-crosslinking

Overview

Journal Arq Bras Oftalmol

Specialty Ophthalmology

Date 2024 Mar 7

PMID 38451681

Authors

Renan Rodrigues

Paulo Schor

Bernardo Kaplan Moscovici

Priscila Guidini

Mario Antonio Stefani

Patricia Alessandra Bersanetti

Affiliations

Soon will be listed here.

Abstract

Purpose: To determine the absorbance coefficient of the thin porcine cornea to ultraviolet-A radiation (365 nm) submitted for crosslinking.

Methods: This in vitro, benchtop experiment using cadaver tissue study analyzed 12 porcine corneal lamellas, which were obtained using a microkeratome after mechanical de-epithelization and separated into three thickness groups: 180, 300, and 360 μm. The corneal thickness values were measured by anterior-segment optical coherence tomography. All lamellas had ultraviolet-A (365 nm) absorbance measured with a 96-well plate spectrophotometer using an ultraviolet transparent microplate before riboflavin instillation and preand post-crosslinking according to the Dresden protocol.

Results: The ultraviolet absorbance profiles of the 180, 300, and 360 μm groups were obtained as α-coefficients of 12.85, 76.55, and 120.27, respectively. A theoretical formula was calculated though a statistical analysis that demonstrated the correlation between stromal lamellar thickness and ultraviolet absorbance.

Conclusions: Corneal thickness and ultraviolet-A spectral absorbance of corneal lamellas showed linear correlation. These findings can potentially contribute to the optimization of ultraviolet-A application during crosslinking, making the treatment of corneas with thickness <400 μm safe and personalized energy delivery for each corneal thickness.

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