A novel numerical modelling approach for keratoplasty eye procedure

Area of Science:

• Biomedical Engineering
• Ophthalmology
• Computational Mechanics

Background:

• Endothelial keratoplasty is a surgical procedure to restore vision by replacing damaged corneal endothelium.
• Understanding the biomechanical forces during graft attachment is crucial for optimizing surgical techniques and outcomes.
• Current methods lack detailed analysis of stress and deformation experienced by corneal tissue and donor grafts.

Purpose of the Study:

• To investigate the stress and deformation in corneal tissue and donor grafts during endothelial keratoplasty.
• To analyze the effect of varying air bubble pressure profiles on graft attachment.
• To evaluate the influence of graft geometrical and material properties on the corneal contact-structural response.

Main Methods:

• Employed a three-dimensional nonlinear finite element methodology.
• Utilized a penalty-based node-to-surface contact algorithm to model the graft-corneal interface.
• Treated ocular tissues as isotropic, hyper-elastic, and nearly-incompressible materials.

Main Results:

• Air bubble pressure profiles significantly influence corneal stress and strain distribution.
• Graft stiffness and thickness were identified as key factors affecting the contact-structural response.
• Von Mises stress intensity, displacement, and mean contact force were quantified.

Conclusions:

• Air bubble pressure is a critical parameter in endothelial keratoplasty, directly affecting corneal biomechanics.
• Finite element analysis provides valuable insights into the mechanical behavior of ocular tissues during surgery.
• Optimizing air bubble pressure and graft properties can potentially improve surgical success rates.