Fig. 1

Quantification and representative photographs of SCD, RCD, R-NPA in normotension and hypertension. A Quantification of SCD at rest and after 2-min VC in both groups; B representative photographs of SCD at rest and after VC in both groups. Hypertensive SCD (b, d) was reduced than the normotensive (a, c) in the rest state and after 2-min VC; C quantification of RCD in both groups; D representative photographs of retinal vessel map and flow density map. Both hypertensive retinal vessel map (b) and flow density map (d) decreased than that in normotension (a, c); E quantification of R-NPA in both groups; F Representative photographs of R-NPA. Yellow zone represented non-perfused areas. Representative photographs of retinal NPA in hypertension (b) increased than that in normotension (a). (B 0.66 mm² per field, magnification 136, scale bar 100 μm; D and F optical axial resolution, 5 microns; optical transverse resolution, 15 microns). VC venous congestion, RCD retina capillary density, R-NPA retinal non-perfused areas