Corneal Cross-Linking: Evaluating the Potential for a Lower Power, Shorter Duration Treatment

Area of Science:

• Ophthalmology
• Biomaterials Science
• Corneal Biomechanics

Background:

• Corneal cross-linking (CXL) strengthens the cornea, primarily using the Dresden protocol.
• The Dresden protocol involves prolonged riboflavin soaking and UV-A irradiation.
• Shorter, lower-energy protocols are being investigated to improve CXL efficiency and patient comfort.

Purpose of the Study:

• To evaluate the efficacy of a modified corneal cross-linking protocol.
• To determine the cross-linking effect of a shorter, lower-energy riboflavin UV-A treatment compared to the standard Dresden protocol.

Main Methods:

• Human corneas were used to measure UV-A transmission through riboflavin-soaked tissue.
• Porcine corneas underwent de-epithelialization or were left intact, followed by riboflavin soaking and irradiation at 1.5 mW/cm for 10 minutes.
• Young's modulus was measured to assess corneal stiffness in treated and untreated porcine corneas.

Main Results:

• Riboflavin oxidation was nearly complete within 10 minutes in the initial experiment.
• UV-A corneal cross-linking at 1.5 mW/cm for 10 minutes with epithelium removal resulted in a 1.99-fold increase in Young's modulus.
• Corneas with intact epithelium showed no significant change in Young's modulus compared to controls.

Conclusions:

• A shortened, lower-energy riboflavin UV-A corneal cross-linking protocol can significantly enhance corneal stiffness.
• This modified protocol achieves results comparable to higher-energy, longer-duration treatments.
• The findings suggest a more efficient approach to corneal cross-linking is feasible.