Comparison of Retinal Microvessel Blood Flow Velocities Acquired with Two Different Fields of View

Figure 1

Comparisons of retinal microvessel blood flow velocity (BFV) measured using RFI with different fields of view (FOVs). Retinal microvessel BFVs centered on the fovea were acquired with the small FOV ((a) 20 degrees, 4.3 × 4.3 mm²) and the wide FOV ((d) 35 degrees, 7.3 × 7.3 mm²). The 35-degree FOV was divided into the inner field (b), equivalent to the 20-degree FOV, and the outer field (c); the peripheral region located beyond the 20-degree FOV BFVs (expressed in mean ± standard deviation) of the secondary and tertiary branches were measured. Arterioles are marked in pink and venules are marked in red. Minus velocity indicates a flow toward the tissue and therefore the vessel is an arteriole. Bars = 500 μm.