Evaluation of macular microvasculature and foveal avascular zone in patients with retinal vein occlusion using optical coherence tomography angiography

Purpose: The aim of the study was to visualize and to quantify pathological foveal avascular zone (FAZ) alterations through optical coherence tomography angiography (OCT-A) in eyes with retinal vein occlusion (RVO) in comparison to the unaffected fellow eyes. Procedures: OCT-A was conducted with the Avanti® RTVue 100 XR system (Optovue Inc., Fremont, Calif., USA). The borders of the superficial vascular layer (SVL) were defined as 3 μm below the internal limiting membrane and 15 μm below the inner plexiform layer, and for the deep vascular layer (DVL) as 15 and 70 μm below the inner plexiform layer, respectively. The length of the horizontal, vertical and maximum FAZ was manually measured for the SVL and DVL in each eye. Additionally, the angle between the maximum FAZ diameter and the papillomacular plane was measured. Results: OCT-A depicted defects within the perifoveal vasculature in eyes with branch retinal vein occlusion (BRVO; n = 11) and central retinal vein occlusion (CRVO; n = 8). These resulted in an enlargement of the maximum FAZ diameter in eyes with RVO (n = 19) in comparison to the healthy fellow eyes (n = 19; 921 ± 213 vs. 724 ± 145 µm; p = 0.008). Furthermore, a significant correlation was found between best-corrected visual acuity (BCVA) and the maximum FAZ diameter in the DVL (Spearman's ρ = -0.423, p < 0.01). Lastly, in the eyes with RVO, the angle between the papillomacular plane and the maximum FAZ diameter was only in 21.05% (SVL) and 15.79% (DVL) of the cases at 0 ± 15 or 90 ± 15°, respectively. In healthy eyes, these angles (which putatively represent a regular FAZ configuration) were more prevalent (SVL 68.42 vs. 21.05%, p = 0.003; DVL 73.68 vs. 15.79%, p < 0.001). Conclusion: OCT-A shows morphological alterations of the FAZ in eyes with CRVO and BRVO. The correlation of the maximum FAZ diameter with BCVA suggests that these alterations are functionally relevant.

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Longitudinal Changes on Optical Coherence Tomography Angiography in Retinal Vein Occlusion

Journal of Clinical Medicine ◽

10.3390/jcm10071423 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1423

Author(s):

Swetapadma Tripathy ◽

Hong-Gam Le ◽

Maria Vittoria Cicinelli ◽

Manjot K. Gill

Keyword(s):

Optical Coherence Tomography ◽

Retinal Vein Occlusion ◽

Optical Coherence Tomography Angiography ◽

Foveal Avascular Zone ◽

Flow Index ◽

Optical Coherence ◽

Longitudinal Changes ◽

Vein Occlusion ◽

Anti Vegf

Background: To evaluate the longitudinal changes on optical coherence tomography angiography (OCTA) in retinal vein occlusion (RVO). Methods: Retrospective study of patients with RVO treated with intravitreal anti-vascular endothelial growth factors (VEGF) for macular edema. Foveal avascular zone (FAZ) area, vessel density (VD), vessel length density (VLD), and adjusted flow index (AFI) were calculated. The unaffected eye of each participant was used as a control. Results: Twelve RVO eyes were included, receiving 6 ± 3 anti-VEGF injections over a follow-up of 10.4 ± 3.1 months. Compared to fellow eyes, RVO eyes had lower VD and VLD at inclusion (p = 0.07 and p = 0.04) and last visit (p = 0.002 and p < 0.001). VD, AFI, and VLD did not change over time, while FAZ area increased in RVO eyes (+0.016 ± 0.024 mm2, p = 0.04). AFI correlated with duration of disease (r = 0.63, p = 0.02). Visual acuity was inversely related to VD and VLD over the follow-up. Conclusions: OCTA parameters remained stable with sustained anti-VEGF treatment in RVO, while changes in the FAZ area may suggest capillary remodeling after RVO.

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Evaluation of Shape of Foveal Avascular Zone by Optical Coherence Tomography Angiography in Eyes With Branch Retinal Vein Occlusion

Journal of VitreoRetinal Diseases ◽

10.1177/2474126418764977 ◽

2018 ◽

Vol 2 (3) ◽

pp. 138-145 ◽

Cited By ~ 2

Author(s):

Hideki Shiihara ◽

Hiroto Terasaki ◽

Shozo Sonoda ◽

Naoko Kakiuchi ◽

Taiji Sakamoto

Keyword(s):

Optical Coherence Tomography ◽

Retinal Vein Occlusion ◽

Branch Retinal Vein Occlusion ◽

Axial Ratio ◽

Cross Sectional Study ◽

Foveal Avascular Zone ◽

Optical Coherence ◽

Cross Sectional ◽

Vein Occlusion ◽

Avascular Zone

Purpose: To determine the relationship between morphological parameters of the foveal avascular zone (FAZ) in the optical coherence tomography angiographic (OCTA) images and the best-corrected visual acuity (BCVA) in branch retinal vein occlusion (BRVO). Methods: This was a retrospective cross-sectional study. Eyes with BRVO without apparent macular edema were studied. The superficial FAZ in 3 × 3 mm OCTA images were delineated manually. The size and shape, the circularity and axial ratio, of the FAZ were determined, and the values were compared to that of the controls. The correlation of these parameters with the BCVA was analyzed. Results: The mean FAZ area was larger in BRVO eyes than in controls, but the larger size was not correlated with the BCVA (BRVO, 0.49 ± 0.12 mm2; control, 0.38 ± 0.12 mm2; P = .135). The axial ratio of the BRVO eyes was significantly larger than that of controls ( P < .001). The axial ratio was significantly correlated with BCVA ( R = .382, P = .050). Although the circularity was significantly smaller in the BRVO eyes than that in controls ( P < .001), it was not significantly correlated with the BCVA. Conclusion: The shape of the FAZ would be a more appropriate parameter than the size in determining BCVA in eyes with BRVO.

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Evaluation of Microvascular Network with Optical Coherence Tomography Angiography (OCTA) in Branch Retinal vein Occlusion (BRVO)

10.21203/rs.2.15193/v1 ◽

2019 ◽

Author(s):

Lulu Chen ◽

Mingzhen Yuan ◽

Lu Sun ◽

Yuelin Wang ◽

Youxin Chen

Keyword(s):

Optical Coherence Tomography ◽

Retinal Vein Occlusion ◽

Branch Retinal Vein Occlusion ◽

Optical Coherence Tomography Angiography ◽

Foveal Avascular Zone ◽

Microvascular Network ◽

Vein Occlusion ◽

Avascular Zone ◽

Radial Peripapillary Capillary ◽

Fellow Eyes

Abstract Purpose: To evaluate changes of microvascular network of macular and peripapillary regions and to provide a quantitative measurement of foveal avascular zone (FAZ) in unilateral BRVO patients. Methods: Forty-seven unilateral BRVO patients were enrolled. A 3*3 mm scan centered on fovea followed by a 4.5*4.5 mm scan centered on optic nerve head (ONH) were obtained in BRVO eyes and fellow eyes of each individual using OCTA (Optovue Inc., Fremont, CA, USA). Vessel density (VD) in superficial (SVC) and deep vascular complex (DVC) of macula and radial peripapillary capillary (RPC) were automatically calculated. Parameters of FAZ region including size, perimeter, acircularity index (AI) and foveal density 300 (FD-300) were measured. Results: VDs of SCV and DVC were significantly lower, especially in affected regions, in BRVO eyes compared with fellow eyes ( P <0.05). BRVO affected eyes has larger FAZ size, FAZ perimeter, AI and lower FD-300 compared with fellow eyes (all P <0.05). The average vessel density in whole area and peripapillary area in BRVO eyes were significantly lower compared with fellow eyes ( P <0.05). Conclusions: OCTA provided quantitative information of vascular changes in BRVO. FAZ in BRVO eyes showed significant morphological alterations and decreases of VD in surrounding area. Decreases of VD existed not only in SVC and DVC in macular region but also in RPCs in BRVO eyes. Key words: optical coherence tomography angiography, retinal vasculature, foveal avascular zone, radial peripapillary capillary, branch retinal vein occlusion

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