Following the status of visual cortex over time in patients with macular degeneration reveals atrophy of visually deprived brain regions.

Background/AimsTo assess the effectiveness, burden and safety of two categories of treatment for central retinal vein occlusion (CRVO): intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) and dexamethasone (Ozurdex).MethodsA retrospective analysis of Medisoft electronic medical record (EMR) data from 27 National Health Service sites in the UK identified 4626 treatment-naive patients with a single mode of treatment for macular oedema secondary to CRVO. Statistics describing the overall CRVO patient cohort and individual patient subpopulations stratified by treatment type were generated. Mean age at baseline, gender, ethnicity, social deprivation and visual acuity (VA) follow-up was reported. Absolute and change in VA using ETDRS are used to describe treatment effectiveness, the number of injections and visits used to describe treatment burden and endophthalmitis rates as a marker of treatment safety.ResultsMean VA was 47.9 and 45.3 EDTRS letters in the anti-VEGF and Ozurdex groups, respectively. This changed to 57.9/53.7 at 12 months, 58.3/46.9 at 18 months and 59.4/51.0 at 36 months. Mean number of injections were 5.6/1.6 at 12 months, 6.0/1.7 at 18 months and 7.0/1.8 at 36 months. Endophthalmitis rates were 0.003% (n=4) for the anti-VEGF group and 0.09% (n=1) for the Ozurdex group.ConclusionsVA improvements were greater and more sustained with anti-VEGF treatment. Lower starting acuity resulted in bigger gains in both groups, while higher starting acuity resulted in higher VA at 36 months. Although treatment burden was greater with anti-VEGF, Ozurdex was associated with higher rates of endophthalmitis.

Purpose The aim of this study was to assess both retinal and cortical structure in a cohort of patients with long-term acquired central retinal disease in order to identify potential disease biomarkers and to explore the relationship between the anterior and posterior visual pathways. Methods Fourteen participants diagnosed with long-term central retinal disease underwent structural assessments of the retina using spectral-domain optical coherence tomography, including macular ganglion cell layer (GCL) and peripapillary retinal nerve fiber layer (pRNFL) thickness. Structural magnetic resonance imaging was used to measure visual cortex, including cortical volume of the entire occipital lobe and cortical thickness of the occipital pole and calcarine sulcus, representing the central and peripheral retina, respectively. Results Mean thickness was significantly reduced in both the macular GCL and the inferior temporal pRNFL across patients. Cortical thickness was significantly reduced in both the occipital pole and calcarine sulcus, representing the central and peripheral retina, respectively. Disease duration significantly correlated with GCL thickness with a large effect size, whereas a medium effect size suggests the possibility that cortical thickness in the occipital pole may correlate with visual acuity. Conclusions Long-term central retinal disease is associated with significant structural changes to both the retina and the brain. Exploratory analysis suggests that monitoring GCL thickness may be a sensitive biomarker of disease progression and reductions in visual cortical thickness may be associated with reduced visual acuity. Although this study is limited by its heterogeneous population, larger cohort studies would be needed to better establish some of the relationships detected between disease dependent structural properties of the anterior and posterior visual pathway given the effect sizes reported in our exploratory analysis.

The aim of this systematic literature review is twofold, (1) detail the impact of retinal biomarkers identifiable via optical coherence tomography (OCT) on disease progression and response to treatment in neovascular age-related macular degeneration (nAMD) and (2) establish which biomarkers are currently identifiable by artificial intelligence (AI) models and the utilisation of this technology. Following the PRISMA guidelines, PubMed was searched for peer-reviewed publications dated between January 2016 and January 2022. Population: Patients diagnosed with nAMD with OCT imaging. Settings: Comparable settings to NHS hospitals. Study designs: Randomised controlled trials, prospective/retrospective cohort studies and review articles. From 228 articles, 130 were full-text reviewed, 50 were removed for falling outside the scope of this review with 10 added from the author’s inventory, resulting in the inclusion of 90 articles. From 9 biomarkers identified; intraretinal fluid (IRF), subretinal fluid, pigment epithelial detachment, subretinal hyperreflective material (SHRM), retinal pigmental epithelial (RPE) atrophy, drusen, outer retinal tabulation (ORT), hyperreflective foci (HF) and retinal thickness, 5 are considered pertinent to nAMD disease progression; IRF, SHRM, drusen, ORT and HF. A number of these biomarkers can be classified using current AI models. Significant retinal biomarkers pertinent to disease activity and progression in nAMD are identifiable via OCT; IRF being the most important in terms of the significant impact on visual outcome. Incorporating AI into ophthalmology practice is a promising advancement towards automated and reproducible analyses of OCT data with the ability to diagnose disease and predict future disease conversion.Systematic Review Registration: This review has been registered with PROSPERO (registration ID: CRD42021233200).