Evaluating corneal biomechanics using shear wave elastography and finite element modeling: sensitivity analysis and parametric optimization

Abstract

This study presents a comprehensive analysis of corneal biomechanics using shear wave elastography, leveraging finite element modeling to investigate the mechanical properties of corneal tissue. A 3D axis-symmetric corneal model was developed and subjected to various simulated conditions, including changes in intraocular pressure (IOP), boundary conditions, excitation pressure, and corneal curvature. The model incorporates hyper-viscoelastic material properties, allowing for an accurate representation of the cornea nonlinear behavior within physiological pressure ranges. Parametric studies were conducted to assess the sensitivity of shear wave velocity to variations in corneal biomechanical parameters. The results revealed that intrinsic material properties, particularly viscoelastic constants, significantly influence shear wave propagation, while external factors such as IOP and boundary conditions have minimal impact. The study also employed the Taguchi method for parametric optimization, identifying the first relaxation time as a critical factor affecting shear wave velocity. This work offers valuable insights into corneal biomechanics, with implications for improving diagnostic techniques and enhancing our understanding of corneal behavior under different physiological conditions. The findings support the potential application of shear wave elastography as a non-invasive tool for assessing corneal stiffness and advancing clinical practice in ophthalmology.