a new method was used to measure corneal elastic modulus of an integrity rabbit cornea
and keratectomy protrusive displacement and stress changes were contrasted . In ex vivo to research biomechanical changes in the cornea of rabbits
excimer laser incision was performed in laser in situ keratomileusis. In the condition of hydrostatic pressure on the corneal inner surface
three corneas such as integrity
1/3 ablation and 1/2 ablation in thickness and 6 mm diameter in central regions were scanned
and the protusive displacement in different corneal centers was calculated. Using Abaqus finite element software to establish the corresponding models
the rabbit corneal elastic modulus with accessed protrusive displacement were calculated. Calculated rabbit corneal elastic modulus increases with increased keratectomy volume. The tendency of the elastic modulus is consistent with the clinical detection. The more stress and the more displacement is in the model of the thinner central region.The displacement and stress are not rapidly changing in ablation border.
关键词
角膜厚度角膜前凸有限元分析弹性模量
Keywords
corneal thinknessprotrusionfinite element analysiselastic modulus
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