Foveal Thickness Fluctuation in Anti-vascular Endothelial Growth Factor Treatment for Branch Retinal Vein Occlusion: A Long-term Study

Relationship between retinal volume changes and the prognosis of BRVO-ME treated with ranibizumab

Background

This study aimed to evaluate the efficacy of ranibizumab for the treatment of macular edema secondary to branch retinal vein occlusion (BRVO-ME), changes in retinal volume and central retinal thickness (CRT) before and after therapy, and the connection between visual prognosis and changes in retinal volume.

Methods

The 120 patients(121 eyes) of BRVO-ME were recruited from July 2020 to October 2022 at the Affiliated Hospital of Weifang Medical University. The clinical data of patients were retrospectively examined for changes in best-corrected visual acuity (BCVA), retinal volume, and CRT at 1 day, 1 week, 1 month, 3 months, 6 months and 1year after treatment.

Findings

Visual acuity improved gradually and became steady approximately 1 months after treatment, whereas retinal volume decreased gradually in both the outer and full layers and stabilized around 6 month after treatment. The decline in retinal volume and CRT was more visible in the deeper layers than in the inner levels. A higher correlation was observed between retinal volume and BCVA than between CRT and BCVA. BCVA after one year of treatment had a high correlation with baseline outer retinal volume.

Interpretation

Treatment of BRVO-ME with ranibizumab is highly effective, and the recovery of visual function was depends more on early treatment. The outer retina is the major site of edema. Changes in retinal volume may serve as a better predictor of visual prognosis than changes in CRT. Baseline ourter retinal volume is correlated with long-term visual prognosis.

Subretinal fluid in macular edema secondary to branch retinal vein occlusion

We identified characteristics of patients with subretinal fluid (SRF) in macular edema (ME) secondary to branch retinal vein occlusion (BRVO) and determined their clinical outcomes after anti-vascular endothelial growth factor (VEGF) treatment. Fifty-seven eyes of BRVO patients with ME were divided into two groups according to the presence or absence of SRF at diagnosis. We compared the aqueous profiles, ocular and systemic characteristics at baseline, and the clinical outcomes. The SRF group had significantly greater central subfield thickness (CST) values and poorer best-corrected visual acuity (BCVA) at baseline compared to the non-SRF group. The former group had significantly higher aqueous levels of interleukin-8, VEGF, and placental growth factor. CST reduction and BCVA improvement during treatment were significantly greater in the SRF group than in the non-SRF group. Consequently, CST values were significantly lower in the SRF group than in the non-SRF group at 12 months, when BCVA did not differ significantly between the two groups. The SRF group required more frequent anti-VEGF treatment over 12 months and exhibited a higher rate of macular atrophy. Based on the aqueous profiles and the number of treatments required, the presence of SRF in BRVO patients appears to be associated with higher disease activity.

The Association between Retinal Thickness Fluctuations and Visual Outcomes under Anti-Vascular Endothelial Growth Factor Therapy: A Systematic Review and Meta-Analysis

INTRODUCTION

The objective of this study was to examine the association between retinal thickness (RT) fluctuations and best corrected visual acuity (BCVA) in eyes with neovascular AMD, macular edema secondary to RVO, and DME treated with anti-VEGF therapy.

METHODS

A systematic search of Ovid MEDLINE, EMBASE, and the Cochrane Library was performed from January 2006 to March 2024. Studies comparing visual or anatomic outcomes of patients treated with anti-VEGF therapy, stratified by magnitudes of RT fluctuation, were included. ROBINS-I and Cochrane RoB 2 tools were used to assess risk of bias, and certainty of evidence was evaluated with GRADE criteria. Meta-analysis was performed with a random-effects model. Primary outcomes were final BCVA and change in BCVA relative to baseline.

RESULTS

15,725 articles were screened; 15 studies were identified in the systematic review and 5 studies were included in the meta-analysis. Final ETDRS VA was significantly worse in eyes with the highest level of RT fluctuation (weighted mean difference [WMD] = 7.86 letters; 95% CI, 4.97, 10.74; p < 0.00001; I2 = 81%; 3,136 eyes). RT at last observation was significantly greater in eyes with high RT fluctuations (WMD = -27.35 μm; 95% CI, -0.04, 54.75; p = 0.05; I2 = 88%; 962 eyes).

CONCLUSIONS

Final visual outcome is associated with magnitude of RT fluctuation over the course of therapy. It is unclear whether minimizing RT fluctuations would help optimize visual outcomes in patients treated with anti-VEGF therapy. These findings are limited by a small set of studies, risk of bias, and considerable heterogeneity.

Computational Retinal Microvascular Biomarkers from an OCTA Image in Clinical Investigation

Retinal structural and functional changes in humans can be manifestations of different physiological or pathological conditions. Retinal imaging is the only way to directly inspect blood vessels and their pathological changes throughout the whole body non-invasively. Various quantitative analysis metrics have been used to measure the abnormalities of retinal microvasculature in the context of different retinal, cerebral and systemic disorders. Recently developed optical coherence tomography angiography (OCTA) is a non-invasive imaging tool that allows high-resolution three-dimensional mapping of the retinal microvasculature. The identification of retinal biomarkers from OCTA images could facilitate clinical investigation in various scenarios. We provide a framework for extracting computational retinal microvasculature biomarkers (CRMBs) from OCTA images through a knowledge-driven computerized automatic analytical system. Our method allows for improved identification of the foveal avascular zone (FAZ) and introduces a novel definition of vessel dispersion in the macular region. Furthermore, retinal large vessels and capillaries of the superficial and deep plexus can be differentiated, correlating with retinal pathology. The diagnostic value of OCTA CRMBs was demonstrated by a cross-sectional study with 30 healthy subjects and 43 retinal vein occlusion (RVO) patients, which identified strong correlations between OCTA CRMBs and retinal function in RVO patients. These OCTA CRMBs generated through this "all-in-one" pipeline may provide clinicians with insights about disease severity, treatment response and prognosis, aiding in the management and early detection of various disorders.

Foveal Thickness Fluctuations in Anti-VEGF Treatment for Central Retinal Vein Occlusion

Purpose

The aim of this study was to examine the effects of foveal thickness (FT) fluctuation (FTF) on 2-year visual and morphological outcomes of eyes with central retinal vein occlusion (CRVO) undergoing anti-VEGF treatment for recurrent macular edema (ME) based on a pro re nata regimen.

Design

Retrospective, observational case series.

Participants

We analyzed 141 treatment-naive patients (141 eyes) with CRVO-ME at a multicenter retinal practice.

Methods

We assessed FT using OCT at each study visit. Patients were divided into groups 0, 1, 2, and 3 according to increasing FTF.

Main Outcome Measures

We evaluated the logarithm of the minimal angle of resolution (logMAR) best-corrected visual acuity (BCVA), the length of the foveal ellipsoid zone (EZ) band defect measured using OCT, and the association of FTF with VA and EZ band defect length.

Results

The mean baseline logMAR BCVA and FT were 0.65 ± 0.52 (Snellen equivalent range: 20/20-20/2000) and 661.1 ± 257.4 μm, respectively. The mean number of anti-VEGF injections administered was 5.6 ± 3.6. At the final examination, the mean logMAR BCVA and FT values were significantly improved relative to the baseline values (both P < 0.01). During the observation, BCVA longitudinally improved in Groups 0 and 1, remained unchanged in Group 2, and worsened in Group 3. Likewise, the length of the foveal EZ band defect did not increase in Group 0; however, it gradually increased in Groups 1, 2, and 3. Foveal thickness fluctuation was significantly and positively associated with the logMAR BCVA and length of the foveal EZ band defect at the final examination (P < 0.01). The final logMAR BCVA of patients developing neovascular complications was 1.27 ± 0.72 (Snellen equivalent range: 20/50-counting fingers), which was significantly poorer than that of patients without complications (P < 0.001). There was no significant difference in the neovascular complication rate among the FTF groups (P = 0.106, Fisher exact test).

Conclusions

In eyes receiving anti-VEGF treatment for CRVO-ME, FTF can longitudinally impair the visual acuity and foveal photoreceptor status during the observation period, thus influencing the final outcomes. However, neovascular complications, which would also lead to a poor visual prognosis, may not be associated with FTF.

Financial Disclosures

The authors have no proprietary or commercial interest in any materials discussed in this article.

Rate and associations of inner retinal thinning in eyes with retinal vein occlusion and regressed macular oedema

PURPOSE

To investigate the associations between visual acuity (VA) and structural optical coherence tomography (OCT) features in retinal vein occlusion (RVO) eyes after cystoid macular oedema (CMO) regression and to assess whether inner retinal thinning is progressive.

METHODS

Retrospective observational study of RVO eyes with regressed CMO for at least 6 months. OCT scans at CMO regression were analysed, and features were correlated with VA at that visit. The inner retinal thickness was longitudinally compared between RVO and unaffected fellow eyes (controls) with linear mixed models. The rate of inner retinal thinning was obtained as the interaction term between disease status and time. Associations between inner retinal thinning and clinical characteristics were explored.

RESULTS

Thirty-six RVO eyes were followed for 34.2 ± 21.1 months after CMO regression. The presence of ellipsoid zone disruption (regression estimate[standard error(SE)] = 0.16[0.04] LogMAR vs. intact, p < 0.001) and lower inner retinal thickness (regression estimate[SE] = -0.25[0.12] LogMAR for 100-μm increase, p = 0.01) were associated with worse VA. The inner retinal thickness decreased faster in RVO than controls (rate of retinal thinning -0.27 ± 0.09 μm/month vs. -0.08 ± 0.11 μm/month, p = 0.01). Macular ischaemia was associated with a faster rate of retinal thinning (interaction term macular ischaemia*follow-up time, p = 0.04).

CONCLUSION

Inner retinal and photoreceptors' layers integrity are associated with better visual acuity once CMO resolves. RVO eyes undergo progressive inner retinal thinning after CMO regression, faster in eyes with macular ischaemia.

Visual Prognostic Factors in Eyes with Subretinal Fluid Associated with Branch Retinal Vein Occlusion

We investigated whether foveal ellipsoid zone (EZ) status affects visual prognosis in eyes with subretinal fluid (SRF) associated with branch retinal vein occlusion (BRVO). We included 38 eyes retrospectively and classified those with or without a continuous EZ on the SRF of the central foveola on the vertical optical coherence tomography (OCT) image at the initial visit as intact (n = 26) and disruptive EZ (n = 12) groups, respectively. In addition, we classified the intact EZ eyes into clear (n = 15) and blurred (n = 11) EZ groups according to whether EZ on the SRF was observed distinctly or not. Multiple regression analyses showed that baseline EZ status significantly correlated (p = 0.0028) with the 12-months logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA), indicating that baseline intact EZ significantly improves visual prognosis. The 12-months logMAR BCVA of the intact EZ group was significantly better (p < 0.001) than that of the disruptive EZ group, and did not differ significantly between the clear and blurred EZ groups. Thus, baseline foveal EZ status on vertical OCT images can be a novel biomarker for visual prognosis in eyes with SRF associated with BRVO.

Characteristics of major and macular branch retinal vein occlusion

We compared the aqueous profiles, baseline characteristics, and clinical outcomes of 54 eyes with macular edema secondary to major branch retinal vein occlusion (BRVO) and macular BRVO. We also identified the characteristics of poor responders to anti-vascular endothelial growth factor (VEGF) injections. Aqueous inflammatory cytokine and VEGF concentrations were significantly higher in major BRVO. In optical coherence tomography, major BRVO had a higher proportion with subretinal fluid, disorganization of retinal inner layers, and ellipsoid zone disruption. Comparing the clinical outcomes, major BRVO required more intravitreal anti-VEGF injections and had a poorer visual prognosis in the first 12 months. A significantly higher proportion of patients with major BRVO required additional treatments after 6 months compared to macular BRVO. Patients who responded poorly to anti-VEGF had higher aqueous VEGF levels and central subfield thickness (CST) at baseline. In conclusion, major BRVO patients required more and longer treatments, and had worse visual prognoses. BRVO that responds poorly to anti-VEGF had greater CST and higher aqueous VEGF levels at baseline.