Purpose To obtain a numerical model of the ocular globe in order to simulate different corneal surgery techniques and to measure changes in geometry and mechanical properties of the cornea.
Methods A biomechanical Finite Element model was created with the geometry of the anterior half of the ocular globe. Each part (cornea, limbus and sclera) has different material properties, and behaviours as hyperelastic anisotropic material. The reference configuration is achieved with initial stresses and then applied the mean physiological intraocular pressure (15 mmHg) during the whole simulation process. In order to validate the model, a serial of arcuate relaxing incisions (o.z. 6 mm) and limbal ones (10 mm) were simulated. One of the principal measurable biomechanical properties of the cornea, which is the Corneal Hysteresis, was also simulated with this model.
Results Regarding the simulation of arcuates and limbal incisions with the model, the obtained results were similar to those stated in different nomograms and surgical in vivo outcomes. The measure of Corneal Hysteresis was reproduced with this model obtaining similar results to measures in vivo performed with the Ocular Response Analyzer (REICHERT). The model can also be useful to simulate other surgical techniques like intracorneal rings, LASIK or keratoplastia. This model is a first approach to a future one which can customize by reproducing a patient specific corneal geometry and material properties.
Conclusion The model was useful to reproduce several surgical techniques and properties measures and offers a lot of possibilities for predicting effects of future surgery techniques.