Abstract
Finite element models (FEM) have been a breakthrough in the field of medicine for a wide variety of applications. They have been used, for example, for predicting the behaviour of many biological structures, as well as to foresee the possible outcomes of some types of operations. One of the basic problems when modelling biological structures is finding a way to determine the initial geometric parameters with a sufficient degree of precision, so that the results are representative. In the case of computational models used for the study of corneal biomechanics, the knowledge of initial conditions defined in a finite element model become critical, since they represent the in-vivo state of the biological structure by means of a computer simulation. There is a lack of consensus among the investigations carried out to date regarding whether the initial status in the FEM models should be considered or not. In this research work, two approaches that aim to determine the geometry of the in-vivo state of the cornea with mild keratoconus have been compared: the so-called stress-free geometry on the one side, and the initial tension state on the other side. The results obtained allow comparisons between them, and validate both approaches when they are used to obtain corneal geometry in initial stress-free conditions for a FEM model when incipient keratoconus.
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Funding
This publication was carried out within the framework of the project “Desarrollo y validación de un nuevo concepto de caracterización biomecánica-morfofuncional de la córnea” reference number DTS21/00103. This Project has been funded by Instituto de Salud Carlos III (ISCIII) and cofunded by the European Union.
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Cavas, F., Gómez, C., Velázquez, J.S., Piñero, D., Sáez-Gutiérrez, F.L., Alió, J. (2022). Adaptative Modelling of the Corneal Architecture in a Free-of-Stress State in Incipient Keratoconus. In: Rojas, I., Valenzuela, O., Rojas, F., Herrera, L.J., Ortuño, F. (eds) Bioinformatics and Biomedical Engineering. IWBBIO 2022. Lecture Notes in Computer Science(), vol 13346. Springer, Cham. https://doi.org/10.1007/978-3-031-07704-3_9
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