Microvascular Retinal and Choroidal Changes in Retinal Vein Occlusion Analyzed by Two Different Optical Coherence Tomography Angiography Devices

Abstract

Purpose: To investigate retinal and choroidal microvascular changes and structural choroidal involvement in retinal vein occlusion (RVO). Methods: Retrospective analysis of treatment-naïve macular edema secondary to RVO, studied by optical coherence tomography (OCT) and OCT angiography (OCTA), before and after the loading phase of intravitreal injections of ranibizumab (IVR-LP). OCTA was performed using two different devices: AngioVue RTVue XR Avanti (spectral-domain OCTA) and Zeiss PLEX® Elite 9000 (swept-source OCTA). Results: 30 eyes of 30 consecutive patients (17 branch and 13 central RVO) were included. Central macular thickness and subfoveal choroidal thickness (SCT) were significantly reduced after IVR-LP (p < 0.001 and p = 0.046, respectively). 23 eyes were eligible for OCTA analysis. Baseline vessel density (VD) in deep capillary plexus (DCP) was significantly reduced in RVO eyes compared with fellow eyes (p = 0.03 and p = 0.002 for PLEX® Elite and AngioVue, respectively). After IVR-LP, no significant VD changes in any vascular layer was found. PLEX® Elite VD analysis showed significant differences in DCP between ischemic versus non-is­chemic eyes (p = 0.011). Conclusion: OCTA suggests a retinal vascular impairment of DCP but no involvement of choroid in RVO eyes. A greater baseline SCT could be due to a choroidal exudation. OCTA imaged with PLEX® Elite allowed to differentiate ischemic and non-ischemic patients at baseline.

Papillary Vessel Density Changes after Intravitreal Anti-VEGF Injections in Hypertensive Patients with Central Retinal Vein Occlusion: An Angio-OCT Study

“…Andrew Winegarner et al [34] found no significant changes in mean VD 12 months after anti-VEGF injections in patients with RVO, although higher VD and a smaller FAZ were associated with better BCVA. Other authors [24,35,36] confirmed no significant variation of macular VD after treatment.…”

“…Recent studies [34,35] focused on vessel density changes and macular perfusion in RVO after anti-VEGF using OCTA technology. Andrew Winegarner et al [34] found no significant changes in mean VD 12 months after anti-VEGF injections in patients with RVO, although higher VD and a smaller FAZ were associated with better BCVA.…”

“…We mentioned above that it is possible to hypothesize that masking effect or retinal vessel displacement due to edema could justify the reappearance of the vessels that were poorly identified before treatment [32,33,34,35].…”

“…As the macular region could be a burdensome site to investigate when severe macular edema is present, other spots should be considered. Some authors [13,35,38] examined the choroidal layer and demonstrated that the choroidal volume (ChV) was greater in RVO eyes than that in fellow eye (FE). Moreover, ChV decreased after intravitreal bevacizumab treatment.…”

“…Rayess et al [38] showed how greater ChV tends to respond better to intravitreal injections, suggesting this parameter as a predictive biomarker to anti-VEGF therapy. In contrast to ChV, studying vessel density of choroidal layer in RVO patients showed no differences between baseline and after anti-VEGF treatment [35]. The masking effect of macular edema could also in this case be a limitation to data acquisition [13].…”