Measuring local flow distributions in mouse retina with contrast-enhanced Doppler OCT

Doppler OCT enables high-resolution, non-invasive measurement of retinal blood flow, but small diving and ascending vessels connecting capillary layers are difficult to visualize due to orientation-dependent signal loss. We combined Doppler OCT with Intralipid contrast enhancement to assess local flow distributions across retinal layers in C57BL/6 mice, acquiring 3D scans at pre-, during, and post-stimulation timepoints using 10Hz flicker stimulation. Flow analysis revealed diverse flow responses in connective vessels, including both increases and decreases in flow after flicker stimulation, with flow values generally not returning to baseline post-stimulation. This approach enables reliable measurement of flow in small vessels and could be combined with visible-light OCT to study local nutrient and oxygen distribution in the retina.