Our second paper focused on crystallinel lens wobbling has been just accepted for publication in Frontiers in Bioengineering and Biotechnology. It's entitled "Investigation of crystalline lens overshooting: ex vivo experiment and optomechanical simulation results" and is a result of our recent collaboration with Applied Mechanics and Bioengineering group from University of Zaragoza.

Abstract:

Introduction: Crystalline lens overshooting refers to a situation in which the lens momentarily shifts too much from its typical location immediately after stopping the rotational movement of the eye globe. This movement can be observed using an optical technique called Purkinje imaging.

Methods: In this work, an experimental setup was designed to reproduce this effect ex vivo using a fresh porcine eye. The sample was rotated 90° around its centroid using a high-velocity rotation stage, and the Purkinje image sequences were recorded, allowing us to quantify the overshooting effect. The numerical part of the study consisted of developing a computational model of the eye, based on the finite element method, that allowed us to understand the biomechanical behavior of the different tissues in this dynamic scenario. A 2D fluid–structure interaction model of the porcine eye globe, considering both the solid parts and humors, was created to reproduce the experimental outcomes.

Results: Outputs of the simulation were analyzed using an optical simulation software package to assess whether the mechanical model behaves optically like the real ex vivo eye. The simulation predicted the experimental results by carefully adjusting the mechanical properties of the zonular fibers and the damping factor.

Conclusion: This study effectively demonstrates the importance of characterizing the dynamic mechanical properties of the eye tissues to properly comprehend and predict the overshooting effect.

Authors:

Ali Dahaghin, Milad Salimibani, Agnieszka Boszczyk, Agnieszka Jóźwik, Marta Skrok, Jorge Grasa, Damian Siedlecki

• Ali Dahaghin is an ESR in the OBERON project funded within the framework of the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 956720.
• Milad Salimibani, Agnieszka Boszczyk, Agnieszka Jóźwik, Marta Skrok and Damian Siedlecki: grant number 2019/35/B/ST7/03998 (National Science Centre, Poland).
• FEM simulations have been carried out using resources provided by Wroclaw Centre for Networking and Supercomputing (http://wcss.pl), grant No. 556.