Impact of aging on anterior segment morphology and aqueous humor dynamics in human Eyes: Advanced imaging and computational techniques

Abstract

Objective

Aging results in significant structural and functional changes in the anterior segment of the eye, influencing intraocular pressure (IOP) and overall ocular health. Although aging is a well-established risk factor for primary open-angle glaucoma, a leading cause of irreversible blindness, the specific mechanisms through which aging drives morphological changes in anterior segment tissues and affects aqueous humor dynamics remain incompletely understood.

Methods

In this study, we employed cutting-edge light sheet fluorescence microscopy (LSFM) to capture high-resolution, volumetric images of cleared human donor eyes’ anterior segment tissues. This advanced imaging enabled a comprehensive morphological analysis of key parameters, including central and peripheral corneal thickness (CCT and PCT), iris thickness, anterior chamber area (ACA), and ciliary body area (CBA). By integrating these morphological parameters with computational fluid dynamics (CFD) models, we analyzed aqueous humor dynamics across n = 6 female human donor eyes, spanning a wide age range of 5 to 94 years (all of Caucasian descent).

Results

The CCT and PCT demonstrated thinning with age, accompanied by a reduction in ACA. In contrast, the CBA remained relatively stable across all age groups. Computational fluid dynamics analysis showed a decline in aqueous humor velocity and wall shear stress, with younger eyes exhibiting higher velocities and shear stress, compared to older eyes.

Conclusion

These findings emphasize the value of integrating LSFM and CFD approaches to provide a detailed understanding of how aging impacts the anterior segment and its fluid dynamics. This study contributes to the understanding of age-related ocular changes, highlighting the importance of considering these changes in the diagnosis and management of age-related eye diseases.