Comparison of Corneal Biomechanical Properties Based on Data from Uniaxial Tensile Test under Fast and Slow Loading / 医用生物力学

ABSTRACT

Objective To compare the corneal biomechanical parameters identified from uniaxial tensile test under fast and slow loading. Methods The stress-strain and stress relaxation data were obtained from uniaxial tensile tests on corneal strips from 15 healthy adult rabbits at average loading rate of 0.16 mm/s and 0.02 mm/s, respectively. A visco-hyperelastic model was applied to analyze the loading and unloading data from the fast tensile tests, where the model parameter set was denoted by Gvh. The first-order Ogden model and second-order Prony series model were used to fit stress-strain and stress relaxation data from the slow tensile tests, respectively, in which the model parameter set was denoted by Gvh. Correlation analysis was used to compare the correlation of parameters between Gvh and GOP. Results All the goodness-of-fits to the three data sets were greater than 0.95. There were significant differences in 5 (μ, A1, A2, τ1, τ2,) of the 6 parameters between Gvh and GOP (P<0.05), and the Ogden model parameters was positively correlated between the two groups. Conclusions There are differences in corneal biomechanical parameters identified by data from uniaxial tensile tests under fast and slow loading. The results provide a preliminary research basis for further exploring the use of clinical data to identify corneal biomechanical properties.