Objective In order to achieve precise operation of continuous circular capsulorhexis (CCC), the finite element analysis (FEA) is used to explore the tear force and anterior capsule deformation during CCC. Methods Firstly, based on the existing clinical physical and morphological data of the lens, a model of continuous circular capsulorhexis was constructed. The damage of the anterior capsule itself and the adjacent tissue between capsule and cortex were simulated by using the distortion energy failure criterion and cohesive model failure criterion, respectively. Then, by constructing a spherical coordinate system to describe the parameters of tearing, the mechanical behavior of tissue was analyzed, and tear force curve was obtained. Results When the capsulorhexis angle 1=90°, 2=30°, the maximum and mean tear force were 19.22 mN and 11.74 mN, respectively. The capsulorhexis force is in good agreement with the experimental data described in literature. The effect of velocity on the mean tearing force is first increased and then decreased, and with the increase of failure stress, the mean tearing force gradually increased. The whole process of capsulorhexis can well reflect the tear force and the deformation of the capsule, and the average force of five tearing steps were 11.74 mN,9.70mN,12.44mN,11.01mN and 9.75mN, respectively. Conclusions In the process of capsulorhexis, the capsule and the cortex are destroyed first, and then the anterior capsule itself is broken. The tear force is mainly caused by the crack propagation of the anterior capsule, and the speed leads to the average tear force first increases and then decreases. At the same time, the increase of failure stress will also cause the increase of tear force. For the entire capsulorhexis process, the tear force after each reversal can remain stable. The finite element model constructed in our paper can simulate the CCC operation.
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