Association of Vascular Versus Avascular Subretinal Hyperreflective Material With Aflibercept Response in Age-related Macular Degeneration

Analyzing Formation and Absorption of Avascular Subretinal Hyperreflective Material in nAMD From OCTA-Based Insights

PURPOSE

To investigate the formation and absorption of avascular subretinal hyperreflective material (avSHRM) in neovascular age-related macular degeneration (nAMD) based on optical coherence tomography angiography (OCTA) characteristics.

DESIGN

Prospective cohort study.

METHODS

This study included patients with treatment-naive nAMD who were followed up for 3 months. Subjects were classified into an avSHRM group and a non-avSHRM group based on the presence of avSHRM at baseline. Quantitative OCTA characteristics including explant area, perimeter, vessel area, density, length, junctions, endpoints, lacunarity, maximum vessel caliber, vessel dispersion, and fractal dimension were assessed, and 3-dimensional volume and optical density ratio (ODR) of avSHRM were measured. Comparison analyses, correlation coefficients, and regression models were applied to explore factors associated with avSHRM formation and absorption.

RESULTS

A total of 88 eyes from 88 patients (39 female) were enrolled. Compared to the non-avSHRM group, the avSHRM group exhibited a more intricate vasculature, characterized by higher values of macular neovascularization (MNV) perimeter, vessel area, total vessel length, total number of junctions, and total number of endpoints (all P < .05), as well as the maximum vessel caliber (P < .001). In the multivariate model, which was adjusted for age, sex, and types of medications, avSHRM absorption was correlated with baseline average vessel length, maximum vessel caliber, and avSHRM ODR (standardized β = 0.274, -0.367, and -0.334; P = .049, .010, and .018, respectively), with an adjusted R² of 0.453.

CONCLUSIONS

Quantitative OCTA measurements can be used for assessing the dynamics of avSHRM in nAMD. Patients with more complex vasculature are at higher risk for avSHRM formation. Average vessel length, maximum vessel diameter, and avSHRM ODR play a role in its absorption.

Deep Learning in Neovascular Age-Related Macular Degeneration

Background and objectives: Age-related macular degeneration (AMD) is a complex and multifactorial condition that can lead to permanent vision loss once it progresses to the neovascular exudative stage. This review aims to summarize the use of deep learning in neovascular AMD. Materials and Methods: Pubmed search. Results: Deep learning has demonstrated effectiveness in analyzing structural OCT images in patients with neovascular AMD. This review outlines the role of deep learning in identifying and measuring biomarkers linked to an elevated risk of transitioning to the neovascular form of AMD. Additionally, deep learning techniques can quantify critical OCT features associated with neovascular AMD, which have prognostic implications for these patients. Incorporating deep learning into the assessment of neovascular AMD eyes holds promise for enhancing clinical management strategies for affected individuals. Conclusion: Several studies have demonstrated effectiveness of deep learning in assessing neovascular AMD patients and this has a promising role in the assessment of these patients.

Subretinal hyperreflective material in regions of atrophy and fibrosis in eyes with neovascular age-related macular degeneration

BACKGROUND

Subretinal hyperreflective material (SHRM) is a significant biomarker for poor visual outcomes in neovascular age-related macular degeneration (nAMD); however, its relationship with fibrosis and atrophy is not well understood. This study aims to evaluate the relationship between SHRM, atrophy, and fibrosis in eyes receiving antivascular endothelial growth factor therapy for nAMD.

METHODS

Post-hoc analysis of the 65 patients enrolled in the SEVEN-UP study, a multicenter cross-sectional study of patients originally enrolled in the ANCHOR and MARINA trials of ranibizumab. Color fundus photographs (CFP) were reviewed and manually segmented to define regions of atrophy and fibrosis. SHRM borders on OCT volume scans were manually delineated, and thickness measurements were computed and compared in corresponding regions of atrophy and fibrosis on the CFPs.

RESULTS

Of the 65 subjects, 51 eyes showed atrophy and/or fibrosis on CFP and were included in the final analysis. Both atrophy and fibrosis regions exhibited SHRM on OCT. The mean SHRM thickness on OCT was significantly greater in CFP-fibrosis regions (44.19 ± 46.95 μm) compared with CFP-atrophy regions (14.28 ± 13.35 μm; p < 0.001). Additionally, the average maximum height of SHRM in fibrotic regions (268.04 ± 130.05 μm) was significantly thicker than in atrophic regions (121.95 ± 51.17 μm; p < 0.001).

CONCLUSIONS

Although atrophy and fibrosis are thought to be different end-stage outcomes in eyes with nAMD, they both demonstrate SHRM on OCT; the main distinction being thickness. Given these similarities, these regions of nAMD-associated atrophy may be better-termed "atrosis" to distinguish these lesions from typical atrophy in the absence of neovascular disease.

Comparative assessment of subretinal hyper-reflective material in patients treated with brolucizumab versus aflibercept in HAWK and HARRIER

PURPOSE

Post hoc analysis of the phase III HAWK and HARRIER studies to compare the reductions in subretinal hyper-reflective material (SHRM) thickness following brolucizumab 6 mg or aflibercept 2 mg treatment and to assess SHRM thickness and thickness variability as a potential biomarker of visual outcomes in patients with neovascular age-related macular degeneration (nAMD).

METHODS

Optical coherence tomography images from the brolucizumab (n=700) and aflibercept (n=696) arms were analysed for the maximum SHRM thickness across the macula over 96 weeks. In a pooled treatment-agnostic analysis, the effect of week 12 SHRM thickness and SHRM thickness variability on best-corrected visual acuity (BCVA) through week 96 were also assessed.

RESULTS

Brolucizumab was associated with numerically higher percentage reductions from baseline in SHRM thickness versus aflibercept in all patients (week 96: 54.4% vs 47.6%, respectively) and also in the matched subgroups with disease activity at week 16 (week 96: 51.6% vs 33.8%, respectively). In eyes with lower SHRM measurements at week 12, mean BCVA gains from baseline were higher at week 96 (<200 µm, +6.47 Early Treatment Diabetic Retinopathy Study letters; ≥200 µm, +3.10 letters). Eyes with the lowest SHRM thickness variability from week 12 to week 96 showed the greatest mean BCVA gains from baseline (week 96: <12 µm, +7.42 letters; >71 µm, -2.95 letters).

CONCLUSIONS

In HAWK and HARRIER, greater reductions in maximum SHRM thickness from baseline were observed with brolucizumab compared with aflibercept. Furthermore, the data suggest that SHRM thickness postloading and SHRM thickness variability over time are biomarkers for visual outcomes in patients with nAMD.

Subretinal hyperreflective material in retinal and chorioretinal disorders: A comprehensive review

Subretinal hyperreflective material (SHRM) is a common and remarkable optical coherence tomography (OCT) biomarker whose importance is emerging in several retinal and chorioretinal diseases, including age-related macular degeneration, central serous chorioretinopathy, polypoidal choroidal vasculopathy, pathologic myopia, posterior uveitis, vitelliform lesions and macular dystrophies, and rarer disorders. Multimodal imaging, also thanks to the introduction of OCT angiography, allowed a deeper characterisation of SHRM components and its morphological changes after treatment, suggesting its usefulness in clinical practice. We discuss and summarize the nature, multimodal imaging characteristics, and prognostic and predictive significance of SHRM in the different retinal and choroidal disorders in which it has been described.

Short-Term Outcomes of 3 Monthly intravitreal Faricimab On Different Subtypes of Neovascular Age-Related Macular Degeneration

Purpose

To evaluate the efficacy and safety of faricimab injections for treatment-naïve neovascular age-related macular degeneration (nvAMD) patients, including subtypes and pachychoroid phenotypes, and identify predictive factors for visual outcomes.

Methods

nvAMD patients were prospectively recruited, receiving three monthly faricimab (6 mg) injections. Best-corrected visual acuity (BCVA) two months after the last injection (month 4) was compared between subtypes, and between pachychoroid neovasculopathy (PNV) and non-PNV eyes. Regression analysis determined factors influencing month 4 BCVA.

Results

The study involved 23 patients (12 typical AMD [tAMD], 10 polypoidal choroidal vasculopathy [PCV], 1 retinal angiomatous proliferation [RAP]). Eleven exhibited PNV phenotype. Significant BCVA (P = 4.9 × 10-4) and central retinal thickness (CRT) (P = 1.3 × 10-5) improvements were observed post-faricimab treatment. The therapy demonstrated favourable results for both tAMD and PCV eyes, and non-PNV and PNV eyes. Faricimab achieved dry macula in 77.3% of eyes, with subretinal fluid resolution in most cases, although intraretinal fluid (IRF) often persisted. Multivariable analysis identified external limiting membrane (ELM) presence and IRF as BCVA contributors at month 4.

Conclusion

Faricimab demonstrated significant effectiveness and safety in treatment-naïve nvAMD patients, particularly for PCV and PNV eyes. ELM presence and IRF is predictive of visual outcomes.

Subretinal Hyperreflective Material (SHRM) as biomarker of activity in Exudative and Non- exudative inflammatory choroidal neovascularization

AIM

To analyze the structural features and therapeutic response in clinical and subclinical inflammatory choroidal neovascularization (i-CNV) detected inside subretinal hyperreflective material (SHRM) using swept-source optical coherence tomography (SS-OCT) and SS-OCT angiography (SS-OCTA).

METHODS

In this prospective interventional study, subjects with quiescent posterior uveitis presenting with SHRM on SS-OCT and CNV network on SS-OCTA were included. Subjects with intraretinal fluid/subretinal fluid (IRF/SRF) received intravitreal antivascular endothelial growth factor (anti-VEGF) injections, while those with no IRF/SRF either received treatment or observation for 6 months until they developed IRF/SRF or decrease in best-corrected visual acuity (BCVA)/metamorphopsia. Serial comparisons included SHRM width and height and intrinsic flow signal on OCTA.

RESULTS

28 eyes of 22 subjects (12 males; mean age: 29.52 ± 12.56 years) were evaluated. Subjects with IRF/SRF at baseline (n = 6 eyes; termed as exudative iCNVs) receiving treatment showed significant improvement in BCVA (p = .017), SHRM width/height and flow signal (p < .05). Among eyes with no IRF/SRF (n = 22; termed as non-exudative iCNVs), 7 received treatment and showed significant improvement in SHRM parameters and BCVA (p < .05). 4/15(26.67%) eyes that received no treatment developed IRF/SRF upon 6-month follow-up.

CONCLUSION

SHRM may act as a useful biomarker to monitor activity and response to therapy in eyes with iCNV.

Morphological characterization of subretinal hyper-reflective material in posterior uveitis using swept-source optical coherence tomography and optical coherence tomography angiography

Purpose

To analyze the structural features of subretinal hyper-reflective material (SHRM) in posterior uveitis using swept-source optical coherence tomography (SS-OCT) and optical coherence tomography angiography (SS-OCTA).

Methods

In this observational study, subjects with quiescent posterior uveitis and the presence of SHRM on SS-OCT were subjected to SS-OCTA to identify the presence of an intrinsic choroidal neovascular (CNV) network. OCT features were compared for SHRM harboring CNV (vascular SHRM) with those without CNV network (avascular SHRM) to identify clinical signs pointing toward the presence of CNVM inside SHRM.

Results

Forty-two eyes of 33 subjects (18 males; mean age: 29.52 ± 12.56 years) were evaluated. Two-thirds (28/42) of eyes having SHRM on SS-OCT harbored intrinsic neovascular network (vascular SHRM). Increased reflectivity of SHRM (P < 0.001) and increased transmission of OCT signal underlying SHRM (P = 0.03) were suggestive of the absence of CNVM. The presence of intra/subretinal fluid (P = 0.08) and pitchfork sign (P = 0.017) were important markers of vascular SHRM.

Conclusion

SHRM is an important OCT finding in eyes with posterior uveitis. Meticulous assessment of SHRM characteristics on SS-OCT can aid in identifying the underlying intrinsic neovascular network.

Bilateral neovascular age-related macular degeneration: unilateral regression following endophthalmitis with persistent activity in the fellow eye

A woman in her 70s who was being followed up for neovascular age-related macular degeneration (nAMD) in both eyes for 2 years with recalcitrant choroidal neovascularisation (CNV) and had an episode of acute endophthalmitis in one eye was identified. After treatment of postinjection culture-negative right eye (RE) endophthalmitis with intravitreal vancomycin and tazobactam, the patient had complete regression of treatment-resistant CNV in RE to date with postinfection follow-up of 2 years. In contrast, the fellow eye continued showing activity in the choroidal neovascular membrane that required antivascular endothelial growth factor injections on a pro re nata basis to date. Prolonged regression of nAMD for 3 years in the affected eye and continued activity in the fellow eye support the hypothesis that inflammation accompanying endophthalmitis or the drugs used for the treatment can have a role in the regression of nAMD.

OCT Biomarkers in Neovascular Age-Related Macular Degeneration: A Narrative Review

Age-related macular degeneration (AMD) is the leading cause of legal blindness in elderly people. Neovascular AMD (nAMD) is responsible for the majority of cases of severe visual loss in eyes with AMD. Optical coherence tomography (OCT) is the most widely used technology for the diagnosis and follow-up of nAMD patients, which is widely used to study and guide the clinical approach, as well as to predict and evaluate treatment response. The aim of this review is to describe and analyze various structural OCT-based biomarkers, which have practical value during both initial assessment and treatment follow-up of nAMD patients. While central retinal thickness has been the most common and one of the first OCT identified biomarkers, today, other qualitative and quantitative biomarkers provide novel insight into disease activity and offer superior prognostic value and better guidance for tailored therapeutic management. The key importance of retinal fluid compartmentalization (intraretinal fluid, subretinal fluid, and subretinal pigment epithelium (RPE) fluid) will be discussed firstly. In the second part, the structural alterations of different retinal layers in various stages of the disease (photoreceptors layer integrity, hyperreflective dots, outer retinal tubulations, subretinal hyperreflective material, and retinal pigment epithelial tears) will be analyzed in detail. The last part of the review will focus on how alterations of the vitreoretinal interface (vitreomacular adhesion and traction) and of the choroid (sub-RPE hyperreflective columns, prechoroidal clefts, choroidal caverns, choroidal thickness and choroidal volume, and choroidal vascular index) interact with nAMD progression. OCT technology is evolving very quickly, and new retinal biomarkers are continuously described. This up-to-date review article provides a comprehensive description on how structural OCT-based biomarkers provide a valuable tool to monitor the progression of the disease and the treatment response in nAMD patients. Thus, in this perspective, clinicians will be able to allocate hospital resources in the best possible way and tailor treatment to the individual patient's needs.

A proof of concept study to evaluate the treatment response of aflibercept in wARMD using OCT-A (Canada study)

PURPOSE

To Utilize OCT-A to measure the change in size (mm²) and density (flow index) of choroidal neovascular membranes (CNVMs) from baseline to week 52 of treatment-naïve wet age-related macular degeneration (wARMD) patients receiving intravitreal aflibercept injections (IAI).

METHODS

Patients were treated with IAI at baseline, month 1 and month 2 and then every other month for a total of 12 months. Along with clinical examination and best corrected visual acuity (BCVA), OCT-A 6- and 3-mm scans were acquired at every visit between May 2017 and January 2019. Data from baseline, week 12 and week 52 were analyzed prospectively and included in the final analysis.

RESULTS

Twenty-five eyes from 23 patients were included in the study. The mean BCVA at baseline and week 52 increased from 20/125 to 20/80, respectively (p < 0.001). The mean CST at baseline and week 52 decreased from 330.48 to 222.40 μm, respectively (p < 0.001). 1Seventeen patients (18 eyes) completed all protocol-based 6 × 6 mm and 3 × 3 mm OCT-A scans. In this subgroup, 6-mm OCT-A scans revealed that the mean size of the CNVM before and after IAI was 1.21 mm² and 0.56 mm², respectively (p < 0.001), while the 3-mm OCT-A scans at baseline and week 52 demonstrated a decrease in mean size of the CNVM from 0.89 to 0.37 mm², respectively (p < 0.001). The 6-mm perfusion density map revealed no difference at either time points.

CONCLUSIONS

OCT-A provides a useful approach for monitoring and evaluating the treatment of intravitreal aflibercept for CNVMs. Mean size of CNVMs can be identified by 3- or 6-mm scans, but without machine learning, it requires extensive segmentation. While reproducibility and clear delineation of CNVMs in wARMD using OCT-A is challenging, OCT-A does offer the ability to monitor CNVM size changes during treatment and may offer another biomarker to assist in assessing treatment response.

Individualizing Therapy for Neovascular Age-Related Macular Degeneration with Aflibercept (VITAL): A Two-Year Prospective, Interventional Single-Centre Trial

AIMS

To report the mean change in Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA) and reading performance (reading acuity and maximum reading speed (MRS) using the MNREAD test) between baseline and 24 months in treatment-naïve patients with neovascular age-related macular degeneration (nAMD) treated with intravitreal aflibercept injections.

METHODS

A prospective, open-label, interventional non-randomised case series with 24 months' duration. Patients were recruited to the study from medical retina clinics at Moorfields Eye Hospital. Intravitreal injections of 2.0 mg aflibercept in the study eye were administered using a fixed dosing regimen during the first year and a treat-and-extend treatment regimen during the second year of treatment.

RESULTS

Fifty patients were enrolled with a mean age (SD) of 78.7 (7.6) years; a mean BCVA of 62.8 ETDRS letters; mean reading acuity of 0.52 logMAR; mean maximum reading speed (MRS) of 141.3 words per minute and a central macular thickness of 322.6 µm at baseline. The mean improvement in BCVA was 6.4 letters for the 44 patients (88%) for whom data was available at 2 years. The mean improvement in reading acuity was 0.13 logMAR with an improvement in MRS of 2.9 words per minute. The mean reduction in CRT from baseline was 104.8 µm.

CONCLUSIONS

Aflibercept treatment of nAMD using fixed dosing in year 1 and treat and extend in year 2 leads to improvements in reading ability, visual acuity and retinal morphology which were maintained to 2 years of treatment.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT02441816, the VITAL study.

Effect of the Duration of Intraretinal or Subretinal Fluid on the Response to Treatment in Undertreated Age-Related Macular Degeneration

We investigated the association between the duration of intraretinal fluid (IRF) or subretinal fluid (SRF) and the response to antivascular endothelial growth factor injection in patients with undertreated age-related macular degeneration (ARMD). The Ethics Committee of Toho University Sakura Medical Center approved this study (no. S18030). Eighty eyes of ARMD patients with VA ≤20/100 were retrospectively assessed. Each injection's efficacy was classified, and the fluid accumulation prior to each injection was evaluated. The effect changes following to accumulated IRF, SRF, the longest persistent IRF period (≥10 months), and their determining factors were evaluated. Throughout observation, acquired refractoriness was rarely associated with increased accumulation of IRF or SRF. The injection span had a tendency to be short, and the polypoidal choroidal vasculopathy and occult choroidal neovasculopathy (CNV) proportions had a tendency to be higher among patients with diminished effects than among those with maintained effects. VA differed significantly with continuous IRF duration, but not with accumulated fluid. The diminishing effect of injections during long-standing IRF was rarely associated with undertreatment. The mechanism underlying acquired refractoriness remains unknown; the effect change demonstrated various patterns, including diminished and improved responses. The longest continuous IRF duration was associated with VA decline. Shortening the duration of continuous IRF may be necessary.

Spectral-Domain Optical Coherence Tomography Analysis of Fibrotic Lesions in Neovascular Age-Related Macular Degeneration

PURPOSE

To describe the spectral-domain optical coherence tomography (OCT) features of fibrotic lesions associated with neovascular age-related macular degeneration (nAMD) and to outline the progression pathways from initial macular choroidal neovascular lesions (CNVs) to fibrosis.

METHODS

Patients with nAMD were retrospectively included when macular subretinal fibrosis was present. Fibrosis was categorized using spectral-domain OCT with respect to retinal pigment epithelium (RPE) in 836 spectral-domain OCT slices from 44 eyes of 39 patients. In addition, in 47 distinct eyes, 4181 spectral-domain OCT slices were retrospectively reviewed to longitudinally assess progression from the initial lesion to the final fibrosis.

RESULTS

Cross-sectional analysis classified fibrosis on spectral-domain OCT slices, as type A if located underneath the RPE, as type B if located above the RPE, and as type C if the remaining RPE was undistinguishable. The longitudinal analysis series revealed 3 progression pathways from the original CNV: 1) progression to type A, followed by RPE erosion and subretinal hyperreflective material, then type B and type C fibroglial lesion (FGL; 17/47 eyes); 2) progression to type B then type C FGL (17/47 eyes); and 3) persistence of type A with development of a flat, fibroatrophic lesion (13/47 eyes). Subretinal hyperreflective material, macular hemorrhage, or RPE tear occurred in 14 of 47, 13 of 47, and 10 of 47 eyes, respectively.

CONCLUSION

This spectral-domain OCT analysis identified various patterns of macular fibrosis in eyes with nAMD. Three pathways of progression to fibrosis were described including the well-established pathway of type 2 CNV progression to FGL and the progression of type 1 fibrovascular CNV to FGL or fibroatrophic lesion.

Clinical multi-functional OCT for retinal imaging

A compact clinical prototype multi-functional optical coherence tomography (OCT) device for the posterior human eye has been developed. This compact Jones-matrix OCT (JM-OCT) device integrates all components into a single package. Multiple image functions, i.e., scattering intensity, OCT angiography, and the degree of polarization uniformity, are obtained. The device has the capability for measuring local birefringence. Multi-functional imaging of several eyes with age-related macular degeneration is demonstrated. The compact JM-OCT device will be useful for the in vivo non-invasive investigation of abnormal tissues.