Dynamic evaluation of corneal cross-linking and osmotic diffusion effects using optical coherence elastography

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Biophysics

Background:

• Dynamic deformation events in post-mortem corneas, caused by osmosis or photochemical stiffening, impact geometrical and mechanical assessments.
• Accurate monitoring of these dynamic processes is essential in experimental settings.

Purpose of the Study:

• To quantify dynamic deformation processes in freshly enucleated porcine corneas using optical coherence elastography (OCE).
• To investigate the effects of osmotic changes and corneal cross-linking (CXL) on corneal biomechanics.

Main Methods:

• Employed OCE to perform high-resolution, volumetric scans of porcine corneas during up to 80 minutes.
• Studied osmotic effects by immersing corneas in media of varying tonicities (n=9).
• Investigated CXL effects using the standard Dresden treatment (n=6) and control groups, analyzing axial deformations between scans.

Main Results:

• Preservation conditions significantly influenced strain patterns, correlating with medium tonicity (swelling in hypotonic, deswelling in hypertonic).
• The CXL group exhibited anterior stromal deswelling within 10 minutes of UV irradiation, a change not seen in controls (p=0.007).

Conclusions:

• OCE is a valuable technique for quantifying subtle, dynamic biomechanical alterations in the cornea.
• OCE can effectively assess changes induced by corneal cross-linking and preservation solutions.