Age-related Macular Degeneration (AMD) is a major cause of global blindness, affecting millions worldwide. Certain forms of AMD cause neovascularizations (NVs), which form retinal-choroidal anastomoses, disrupting healthy hemodynamics. Early detection and treatment are crucial for preserving vision. We employ a custom-built OCT imaging system to investigate these NVs in a VLDLR−/− knockout mouse model. This included imaging the mouse before, during, and after contrast agent injection, aiming to enhance our understanding of the NV hemodynamics. Doppler signal analysis techniques were employed to calculate flow velocities within individual NVs. Flow rates pre- and post-injection were determined based on these velocity measurements. Particle tracking was performed on two NVs for a comparative analysis with the Doppler velocity measurements. Both methods of measuring flow velocities showed good agreement post-contrast injection. The analysis of post-injection flow rates from the NVs revealed diverse behaviors. Some NVs exhibited stable flow rates over time, while others showed signs of instability with flow rates changing substantially or even changing flow direction at different time points. Additionally, it was observed at multiple time points that flow from certain NVs moved from the choroid to the retina at the same time that others displayed flow in the opposite direction. These observations suggest complex interactions between choroidal and retinal vascular networks in disease model eyes like AMD. Further characterization using contrast-enhanced Doppler OCT can improve our understanding of neovascular hemodynamics.
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