[Experimental study on corneal biomechanical properties of rabbit eye after LASIK]

The biomechanical properties of 21 white New Zealand rabbits' corneas after Laser in situ keratomileusis (LASIK) were tested by use of one-dimension tensile test and creep test in the INSTRON 5544 mechanical machine. The cornea-related data from the experiments of one-dimension tensile test and creep test for an hour were obtained; a standard linear solid model was adopted to analyse the data, and the least square method was used to fit the viscoelastical coefficients of creep experiment on different corneas. We noticed there was certain difference between the LASIK groups and the normal group in respect to the corneal modulus of elasticity, the stiffness coefficients diminished with the increase of ablation depth; the anti-tensile ability of corneas also displayed some reduction. These findings indicate that the deeper the ablation goes, the easier will be the deformation after LASIK.