Characterization of the transient mechanical properties of human cornea tissue using the tensile test simulation

There are potential problems in utilizing the material laws in numerical simulations due to the presence of both geometry nonlinearities and material nonlinearities. In this study, eight material parameters of the structural anisotropic fiber-reinforced hyper-viscoelastic model of Cornea with various fiber angles (8, 18, 22.5, and 45 degrees) have been obtained using coupled finite element-optimization analysis and experimental data. The utilized model considers the dispersion of the fibers along with their reorientation during loading, the nonlinear behavior of finite tissue deformation, and the intrinsic viscoelastic property of the matrix. The effect of each parameter on the sample responses in the tensile test simulation was examined. The results demonstrated that the J-shape behavior of the samples under the tensile test can be justified by the model used in the present study. Examining the results shows that the numerical simulations performed for the prediction of the cornea tissue behavior are nearly consistent with the experimental results and have good accuracy and that the model has acceptable stability. Therefore, an unprecedented opportunity has been provided to create numerical simulations for accurate prediction of corneal response to disease, injury, and surgery. The ability of the proposed model in predicting the human corneal behavior illustrates a promising future for numerical simulation in the corneal microsurgery field.

Automated summary

This study addresses the potential problems in utilizing material laws in numerical simulations due to geometric and material nonlinearities. By obtaining material parameters through finite element-optimization analysis and experimental data, the model shows promising accuracy and stability in predicting corneal tissue behavior, providing an unprecedented opportunity for accurate numerical simulations in corneal microsurgery. The J-shape behavior of the samples under tensile test can be justified by the model used, demonstrating the model's capability in predicting human corneal behavior.