Multi-contrast optical coherence tomography for in vivo visualization and quantification of vascular features and collagen in mouse ovaries in aging

This is the authors' abstract. We don't add key points for this paper.

Multi-contrast optical coherence tomography (MC-OCT), incorporating optical coherence tomography angiography (OCTA) and polarization-sensitive OCT (PS-OCT), offers a powerful non-invasive approach for interrogating ovarian microvascular and extracellular matrix (ECM) remodeling in vivo . However, its application to ovarian aging has remained largely unexplored. Here, we establish and validate MC-OCT as a robust imaging platform for visualizing and quantifying age-related changes in vascular architecture and collagen organization in mouse ovaries. Using in vivo OCTA, we demonstrate a progressive decline in ovarian microvascular density, complexity, and connectivity with advancing age. Complementary PS-OCT imaging reveals increased collagen-associated birefringence, indicative of fibrotic ECM remodeling. Quantitative OCT-derived metrics show strong agreement with histological validation using immunohistochemistry, second harmonic generation microscopy, and Sirius Red staining, confirming the accuracy and reproducibility of MC-OCT measurements. Importantly, MC-OCT enables longitudinal, real-time assessment of ovarian structure without tissue disruption, allowing detection of age-dependent remodeling that is not accessible with conventional ex vivo methods. Together, these findings establish MC-OCT as a sensitive and reliable tool for non-destructive evaluation of ovarian vascular and fibrotic changes, providing a valuable platform for studying ovarian aging and assessing interventions aimed at preserving reproductive health.