Consequently, the outer retinal vasculature slab increased in thickness and was renamed the deep vascular complex, comprised of the intermediate capillary plexus and deep capillary plexus. The outer limit of this inner retinal vasculature was shifted inward (toward the inner limiting membrane), from the inner nuclear layer to the inner plexiform layer, and was renamed the superficial vascular complex (SVC) slab, as it includes two vascular plexuses: radial peripapillary capillary plexus and superficial vascular plexus. In the previous software version, the superficial retinal vessel (SRV) slab incorporated flow signals from three separate anatomic layers, including nerve fiber, ganglion cell, and inner plexiform layers. These new boundaries were adopted by the AngioVue software upgrade from Phase 6.5 to Phase 7.0 and applied to VD measurements of the inner retinal vasculature. 17 redefined the boundaries among four retinal capillary plexuses. 2, 7, 8, 10 – 16 Based on recent clinicohistological correlations, Campbell et al. Several reports have been published on normative values delivered by the instruments, and many studies have examined the intra- and inter-session repeatability of retinal layer thickness and superficial capillary density measurements from the RTVue XR Avanti SD-OCT. 9 The AngioVue software allows retinal thickness (RT) and vessel density (VD) to be calculated from selected regions of the retina. The AngioVue Imaging System (RTVue XR Avanti, Optovue Inc., Fremont, CA, USA) is a spectral-domain optical coherence tomography (SD-OCT) device that enables simultaneous three-dimensional (3D) structural imaging of the retina and generation of en face maps of blood flow through a split-spectrum amplitude decorrelation angiography algorithm. RT and VD measures derived from the newer AngioVue software version are not directly comparable to the reported normative data derived from the older software. The AngioVue software upgrade resulted in an unexpected increase in total RT and an expected reduction in inner retinal VD measurements in all regions due to altered segmentation. Mean (LA) foveal inner retinal VD decreased by 6.6 (2.5–11) and 7.7 (0.4–15) percentage units ( P < 0.001) and parafoveal inner retinal VD decreased by 4.1 (1.2–7.0) and 4.7 (0.5–8.9) percentage units ( P < 0.001) in healthy and diseased retina, respectively. The mean (SD) age of participants was 46 (17) years. Bias and limits of agreement (LA) were calculated. Total RT and inner retinal VD values were extracted before and after the software upgrade for comparison. Optovue OCTA images (3 × 3 mm) from 126 individuals (105 healthy eyes and 72 eyes with retinal disease) were acquired before an upgrade of the AngioVue software, which resulted in an inward shift of the outer boundary of the inner retinal vessels and improved Bruch's membrane segmentation. To determine the impact of an AngioVue software upgrade on total retinal thickness (RT) and inner retinal vessel density (VD) measurements derived from optical coherence tomography angiography (OCTA).
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