Quantitative microvascular analysis of retinal venous occlusions by spectral domain optical coherence tomography angiography

Abstract

PurposeTo quantitatively evaluate the retinal microvasculature in human subjects with retinal venous occlusions (RVO) using optical coherence tomography angiography (OCTA).DesignRetrospective, cross-sectional, observational case series.ParticipantsSixty subjects (84 eyes) were included (20 BRVO, 14 CRVO, 24 unaffected fellow eyes, and 26 controls).MethodsOCTA was performed on a prototype, spectral domain-OCTA system in the 3x3mm central macular region. Custom software was used to quantify morphology and density of retinal capillaries using four quantitative parameters. The vasculature of the segmented retinal layers and nonsegmented whole retina were analyzed.Main outcome measuresFractal dimension (FD), vessel density (VD), skeletal density (SD), and vessel diameter index (VDI) within the segmented retinal layers and nonsegmented whole retina vasculature.ResultsNonsegmented analysis of RVO eyes demonstrated significantly lower FD (1.64±0.01 vs 1.715±0.002; p<0.001), VD (0.32±0.01 vs 0.432±0.002; p<0.001), and SD (0.073±0.004 vs 0.099±0.001; p<0.001) compared to controls. Compared to the fellow eye, FD, VD and SD were lower (p<0.001), and VDI was higher (p<0.001). FD, VD, and SD progressively decreased as the extent (or type) of RVO increased (control vs BRVO vs CRVO; p<0.001). In the unaffected fellow eye FD, VD and SD showed significant differences when compared to control eyes or affected RVO eyes (p<0.001).ConclusionsQuantitative OCTA of the central 3x3mm macular region demonstrates significant differences in capillary density and morphology among subjects with BRVO and CRVO compared to controls or unaffected fellow eyes in all vascular layers. The unaffected fellow eyes also demonstrate significant differences when compared to controls. OCTA allows for noninvasive, layer-specific, quantitative evaluation of RVO-associated microvascular changes.

Evaluation of retinal nonperfusion in branch retinal vein occlusion using wide‐field optical coherence tomography angiography

“…In eyes with BRVO, decrease in VD and VL are also reported in 3 × 3 mm scan area which is much more limited compared with current study (Koulisis et al. ). As we stated, few reports have assessed the efficacy of wide‐field OCTA so that VL can be the marker of development on retinal nonperfusion in BRVO.…”

Repeatability, interocular correlation and agreement of quantitative swept-source optical coherence tomography angiography macular metrics in healthy subjects

“…Existing studies have reported enlarged foveal avascular zone (FAZ) area in retinal ischaemic diseases such as diabetic retinopathy (DR)10 and retinal vascular obstruction (RVO)11; decreased FAZ area in retinopathy of prematurity12; decreased vessel density in DR10 and glaucoma13; lower fractal dimension in RVO,11 DR10 and uveitis eyes14; increased vessel diameter index (VDI) in RVO11 and DR10; and decreased FAZ circularity in glaucoma15 and DR 10. These studies demonstrate that quantitative OCTA metrics may provide useful information for the diagnosis of ocular diseases potentially.…”

An Automated 3D Analysis Framework for Optical Coherence Tomography Angiography

“…Multivariable linear regressions were used to compare the 3Dmeasures across groups. The generalized estimating equation (GEE) method was used to control for age, gender, and between-eye correlation when appropriate [6]. All statistical analysis was considered significant for p-value set to 0.05.…”

“…Optical Coherence Tomography Angiography (OCTA) is a novel and non-invasive modality that is clinically approved to evaluate the retinal vasculature [1][2][3]. It has been applied in studying various ophthalmological diseases such as age-related macular degeneration (AMD), diabetic retinopathy (DR), uveitis, vein occlusions, and glaucoma [4][5][6][7][8][9]. In addition, OCTA has been shown to be a valuable imaging modality to identify changes in the microvascular network caused by neurovascular diseases [10][11][12][13].…”