Persistent macular edema (ME) secondary to branch retinal vein occlusion (BRVO) may show a limited anatomical response to anti-vascular endothelial growth factor (VEGF) therapy despite apparent control of vascular leakage. In this non-interventional observational study, we examined whether retinal microstructural alterations beneath foveal cystoid spaces are associated with anatomical characteristics of persistent macular edema following standard anti-vascular endothelial growth factor therapy. Thirty eyes of 30 patients with persistent BRVO-related ME (≥ 6 months after onset) underwent adaptive optics optical coherence tomography (AO-OCT). Retinal microstructural organization and ellipsoid zone (EZ) integrity beneath the foveal cystoid space were evaluated, and anatomical response was assessed by the reduction in central subfield thickness (CST) after the final anti-VEGF injection. Eyes with retinal microstructural disorganization showed significantly smaller CST reductions than those with preserved retinal alignment (P = 0.019). Microstructural disorganization was also associated with greater EZ disruption (P < 0.001) and a lower density of high-intensity dots in the outer nuclear layer (P = 0.009). In contrast, macular vessel density reduction assessed by OCT angiography was not significantly associated with CST reduction. These findings suggest that retinal microstructural integrity beneath foveal cystoid spaces is associated with the anatomical response to anti-VEGF therapy in persistent BRVO-related ME.

Clinical decision support systems (CDSS) increasingly rely on artificial intelligence (AI) to interpret biomedical images and provide accurate, real-time diagnostics. Federated Learning (FL) has emerged as a promising privacy-preserving solution for training AI models across decentralized healthcare institutions. However, FL performance is significantly affected by data heterogeneity-especially when client data is non-independent and identically distributed (non-IID), a common occurrence in clinical practice. In this study, we propose a dynamic FL framework specifically designed for Retinal Vein Occlusion (RVO) detection that enhances the adaptability and robustness of CDSS. The core contribution of our approach is a server-side aggregation strategy that selects FedAvg for IID data and SCAFFOLD for non-IID data based on monitoring the normalized L2 divergence between successive communication rounds. This intelligent selection mechanism ensures stable convergence, improves diagnostic accuracy, and supports reliable model performance across diverse healthcare environments. Experimental results show that the proposed approach was evaluated on a two-class RVO dataset across five simulated clients under both IID and non-IID data distributions. By addressing real-world data distribution challenges, this work offers a practical path toward integrating FL-based AI systems into clinical workflows for more effective and trustworthy medical image analysis.

Anti-vascular endothelial growth factors (anti-VEGFs) are agents that block the activity of specific bio-active molecules responsible for the growth of abnormal blood vessels. The advent of anti-VEGF therapy has revolutionized the treatment of retinal diseases. They are commonly indicated for diabetic macular edema, choroidal neovascular membrane, cystoid macular edema due to retinal vein occlusion, neovascular glaucoma, and retinopathy of prematurity. The commonly available anti-VEGF agents are bevacizumab, ranibizumab, aflibercept, brolucizumab, and faricimab. The currently practiced treatment regimens include fixed dosing, pro-re-nata, and treat-and-extend. Additionally, biosimilars represent a pivotal shift, offering cost-effective alternatives without compromising therapeutic value. Studies on sustained release anti-VEGF medications like port delivery systems and biodegradable depots are yielding promising outcomes. Ongoing studies analyze the long-term effects of anti-VEGF therapy, aiming to develop next-generation agents with greater durability, efficacy, and safety. This further reduces the treatment burden and offers an extra edge in optimizing long-term visual outcomes. This article provides a comprehensive overview of anti-VEGF therapies including their mechanism of action, efficacy and safety profiles, and landmark trials that have shaped their use in clinical practice. This was a narrative review of the literature that was conducted using PubMed, MEDLINE, Scopus Cochrane library databases, and Google Scholar databases.

Vascular endothelial growth factor (VEGF) plays a central role in the pathogenesis of retinal and choroidal neovascularization, as well as macular edema (ME), in retinal disorders such as diabetic retinopathy, retinal vein occlusion (RVO), and age-related macular degeneration (ARMD). The advent of intravitreal anti-VEGF therapy has revolutionized their management. More recently, these agents have been explored in several other retinal pathologies characterized by secondary neovascularization, either in vascular or non-vascular disorders. This review summarizes current evidence on the role of anti-VEGF agents in retinal disorders other than ARMD, including central serous chorioretinopathy (CSCR), macular telangiectasia type 2 (MacTel), choroidal osteoma, retinopathy of prematurity (ROP), tubercular granuloma, inherited retinal dystrophies, Coats' disease, angioid streaks, and retinal vasoproliferative tumors (RVPTs).

This narrative review examines the "efficacy-effectiveness gap" in anti-vascular endothelial growth factor (anti-VEGF) therapy by comparing outcomes from randomized controlled trials (RCTs) with global and Indian real-world evidence (RWE) in neovascular age-related macular degeneration (nAMD), diabetic macular edema (DME), and retinal vein occlusion (RVO). Across all three conditions, real-world outcomes consistently fall short of those observed in RCTs. In nAMD, studies such as AURA report minimal visual gains by Year 2 (+0.6 letters) compared to +8 to +10 letters in RCTs, largely attributable to fewer injections administered in practice. Indian data, including the ARMOUR study, reflect similarly reduced injection frequencies alongside issues such as delayed presentation. For DME, global RWE demonstrates modest improvements in visual acuity with fewer injections per year than in RCTs, while Indian cohorts show even lower treatment intensity, resulting in anatomical stabilization without meaningful visual gains. Outcomes in RVO are also compromised by incomplete loading doses and inadequate follow-up. The primary drivers of this gap include undertreatment, variability in patient populations, and socioeconomic barriers that affect adherence and access to care. Overall, the discrepancy appears to stem more from real-world treatment challenges than from limitations of the therapies themselves. Addressing this gap will require practical approaches such as implementing Treat-and-Extend regimens, promoting earlier diagnosis and intervention, enhancing patient engagement, and increasing the use of cost-effective or longer-acting treatment options, particularly in resource-constrained settings like India.

Retinal vascular diseases, including neovascular age-related macular degeneration, diabetic macular edema, retinal vein occlusion, myopic choroidal neovascularization, and retinopathy of prematurity, are a major cause of visual morbidity in India. Although anti-vascular endothelial growth factor (anti-VEGF) therapy has transformed the management of these conditions, long-term outcomes in real-world Indian practice are frequently limited by affordability-related undertreatment. The introduction of biosimilar anti-VEGF agents, particularly ranibizumab biosimilars, has therefore assumed critical importance in improving access to sustained retinal care. This narrative review synthesizes the available Indian evidence on the clinical efficacy, safety, immunogenicity, and cost-effectiveness of biosimilar anti-VEGF agents. A comprehensive literature search was conducted in PubMed, MEDLINE, EMBASE, and Scopus from inception through September 2025 using predefined keywords related to biosimilar ranibizumab, retinal vascular diseases, safety, immunogenicity, real-world evidence, and cost-effectiveness. Additional studies were identified through manual screening of reference lists. Peer-reviewed English-language randomized trials, phase 3 studies, post-marketing surveillance reports, and large real-world cohorts from India were included. Across major retinal indications, phase 3 trials consistently demonstrated equivalence or noninferiority of biosimilars to the reference molecule in visual and anatomical outcomes, with comparable safety and low immunogenicity. Large real-world datasets further corroborate these findings and provide reassurance regarding ophthalmic use of biosimilar anti-VEGF. Importantly, reduced treatment costs have translated into improved treatment initiation and adherence. Overall, current evidence supports biosimilar ranibizumab as a safe, effective, and cost-effective alternative for retinal diseases in resource-limited settings.

Macular edema is the leading cause of visual impairment in retinal vein occlusion (RVO). Management has evolved significantly with advances in retinal imaging and the recognition of vascular endothelial growth factor (VEGF) as a key pathogenic mediator. Anti-VEGF agents are now the mainstay of treatment, supported by robust evidence from randomized clinical trials and real-world studies. Intravitreal corticosteroids play a selective role in patients with suboptimal anti-VEGF responses or contraindications to anti-VEGFs, while the role of laser photocoagulation has become limited. Optical coherence tomography remains central to diagnosis, monitoring, and prognostication. Fluorescein angiography and optical coherence tomography have a role in assessing retinal perfusion, including the macula. Emerging therapies, including biosimilars and long-acting delivery systems, aim to increase accessibility and durability of treatment in RVO-related macular edema (RVO-ME). This review summarizes current evidence and future directions in the management of RVO-ME.