Optobiomechanics of the Eye: Advances, Insights, and Emerging Directions

Sabine Kling^1*Anna Marina Pandolfi²Norberto López Gil³Jos J. Rozema⁴

• ¹University of Bern, Bern, Switzerland
• ²Politecnico di Milano, Milan, Italy
• ³Universidad de Murcia, Murcia, Spain
• ⁴Universiteit Antwerpen, Antwerp, Belgium

The relationship between IOP and ocular biomechanics has been investigated at multiple levels, from tissuespecific alterations to whole-eye deformation responses. B. Ma et al. explored how chronic high IOP alters the mechanical properties of the lamina cribrosa (LC) and retinal ganglion cell (RGC) axons. Using atomic force microscopy on a rat glaucoma model, the authors documented a time-dependent reduction in stiffness of both LC glial tissue and RGC axons, with up to 80% loss in modulus over 12 weeks. This weakening likely contributes to axonal vulnerability and progressive glaucomatous damage, emphasizing the need for therapies that preserve or restore LC integrity. Extending the focus from local tissue mechanics to global ocular responses, two other studies applied air-puff tonometry to connect corneal and scleral responses to IOP. E. Redaelli et al. developed a computational model to simulate corneal deformation under air-puff tonometry, addressing the fact that traditional measures are confounded by corneal thickness and the tissue's mechanical properties. By shifting the analysis toward the timing of maximum apex velocity, the authors propose a more reliable IOP estimator less dependent on corneal properties. Using the same air-puff tonometry, A. De La Hoz et al. examined scleral biomechanics in rabbits in combination with computational modeling. Their findings showed scleral stiffness strongly influences deformation responses, suggesting that this non-invasive tool could provide valuable biomechanical markers for myopia and glaucoma risk evaluation. Although crucial to the process of accommodation, the biomechanical behavior of the crystalline lens is not yet entirely understood. A. Dahaghin et al. introduced a biomechanical model of lens "wobbling," the oscillatory motion that occurs after rapid eye movement. By combining Purkinje image analysis with optobiomechanical simulations, the authors reproduced oscillation frequencies and damping factors observed in vivo, while also revealing subject-specific variability. This work sets the stage for personalized lens models that could deepen our understanding of ocular biomechanical mechanisms. V. Tahsini et al. examined how preservation methods alter the mechanical properties of ex vivo porcine lenses. Using optical coherence elastography and inverse finite-element analysis, the authors showed that freezing significantly alters cortical and nuclear strains, while refrigeration preserves the lens' mechanical properites best. Removal of the capsule changed the strain distribution across lens nucleus and cortex. These findings are essential for interpreting ex vivo experiments and designing standardized protocols for lens biomechanics research. Taken together, these eleven contributions provide a rich insight in the evolving field of optobiomechanics. From synchrotron scattering to, air-puff tonometry, OCT elastography, machine learning and numerical simulations, diverse methods are converging to give a more complete picture of ocular biomechanics. Studies on corneal cross-linking, scleral stiffness, and lamina cribrosa degradation deepen our understanding of disease and treatment mechanisms. Computational models and predictive algorithms are directly informing refractive surgery screening and IOP measurement, while non-invasive imaging modalities offer prospects for routine biomechanical monitoring. The continued growth of optobiomechanics will rely on interdisciplinary collaborations across physics, biology, engineering, and clinical sciences, ultimately driving innovations that improve patient care and visual performance.