Biomechanical characterization of ex-vivo crystalline lenses using non-contact optical coherence elastography

The crystalline lens plays an important role in focusing light on the retina by a process called accommodation. Accommodation is inherently biomechanical as it involves reshaping the lens to adjust its optical power. Hence, assessing the biomechanical properties of the crystalline lens will improve our understanding of accommodation. Lens viscoelasticity changes are correlated to various eye conditions, such as cataract and presbyopia. Optical coherence elastography (OCE) is an established technique to quantify the mechanical properties of biological tissues and is particularly well-suited for characterizing the lens. Here, we utilize a non-contact OCE method utilizing air-coupled ultrasound excitation to quantify the stiffness of ex-vivo porcine lenses with and without the capsule. Phase-sensitive optical coherence tomography imaging was used for tracking mechanical wave propagation. The results show the lenticular stiffness significantly decreased after removal of the capsule, and that OCE has the potential to be used for in vivo investigations of lenticular mechanical properties.