Type 3 neovascularization: evolution, association with pigment epithelial detachment, and treatment response as revealed by spectral domain optical coherence tomography

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.

Rediscovering Age-Related Macular Degeneration with Swept-Source OCT Imaging: The 2022 Charles L. Schepens, MD, Lecture

PURPOSE

Swept-source OCT angiography (SS-OCTA) scans of eyes with age-related macular degeneration (AMD) were used to replace color, autofluorescence, infrared reflectance, and dye-based fundus angiographic imaging for the diagnosis and staging of AMD. Through the use of different algorithms with the SS-OCTA scans, both structural and angiographic information can be viewed and assessed using both cross sectional and en face imaging strategies.

DESIGN

Presented at the 2022 Charles L. Schepens, MD, Lecture at the American Academy of Ophthalmology Retina Subspecialty Day, Chicago, Illinois, on September 30, 2022.

PARTICIPANTS

Patients with AMD.

METHODS

Review of published literature and ongoing clinical research using SS-OCTA imaging in AMD.

MAIN OUTCOME MEASURES

Swept-source OCT angiography imaging of AMD at different stages of disease progression.

RESULTS

Volumetric SS-OCTA dense raster scans were used to diagnose and stage both exudative and nonexudative AMD. In eyes with nonexudative AMD, a single SS-OCTA scan was used to detect and measure structural features in the macula such as the area and volume of both typical soft drusen and calcified drusen, the presence and location of hyperreflective foci, the presence of reticular pseudodrusen, also known as subretinal drusenoid deposits, the thickness of the outer retinal layer, the presence and thickness of basal laminar deposits, the presence and area of persistent choroidal hypertransmission defects, and the presence of treatment-naïve nonexudative macular neovascularization. In eyes with exudative AMD, the same SS-OCTA scan pattern was used to detect and measure the presence of macular fluid, the presence and type of macular neovascularization, and the response of exudation to treatment with vascular endothelial growth factor inhibitors. In addition, the same scan pattern was used to quantitate choriocapillaris (CC) perfusion, CC thickness, choroidal thickness, and the vascularity of the choroid.

CONCLUSIONS

Compared with using several different instruments to perform multimodal imaging, a single SS-OCTA scan provides a convenient, comfortable, and comprehensive approach for obtaining qualitative and quantitative anatomic and angiographic information to monitor the onset, progression, and response to therapies in both nonexudative and exudative AMD.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Effect of Pro Re Nata Regimen with Anti-VEGF on Type 3 Macular Neovascularization: Long-Term Outcomes

INTRODUCTION

The purpose of this study was to investigate long-term outcomes of intravitreal injections (IVI) of antivascular endothelial growth factor (VEGF) in neovascular age-related macular degeneration (nAMD) with type 3 macular neovascularization (MNV).

METHODS

This retrospective study included 19 eyes of 17 patients with nAMD and type 3 MNV treated with anti-VEGF IVI with a loading dose and a PRN regimen. Best corrected visual acuity (BCVA), central macular thickness (CMT), presence of macular intraretinal fluid (IRF) and subretinal fluid (SRF), flow area (FA), subfoveal choroidal thickness (CT), and macular atrophy (MA) were assessed at baseline (T0) and during follow-up (T1, post-loading phase; T2, 1 year; T3, 2 years; T4 >2 years). The correlations between MA at the last follow-up and standard deviation (SD) values of CMT and CT during follow-up were assessed. The influence of the number of injections on the change in MA over time was also analyzed. MA differences at T4 were assessed for pseudodrusen presence.

RESULTS

BCVA improved significantly during follow-up (p = 0.013) particularly increasing from baseline to post-loading phase and then did not modify significantly thereafter. CMT significantly reduced from T0 to T1 and remained stable during follow-up (p = <0.001). MNV flow area showed a trend toward an increase in the post-loading phase that was not statistically significant (p = 0.082) and CT decreased significantly during follow-up (p < 0.001). MA changed significantly during follow-up (p < 0.001) with a significant increase from T0 to T3 and from T0 to T4 (p < 0.010). A Cochran-Armitage test for trend showed a significant reduction (p = 0.001) of macular IRF and SRF during follow-up. MA at T4 showed a significant positive correlation with SD (standard deviation) values of CMT (p = 0.040) and CT (p = 0.020). Indeed, the number of injections did not influence the change over time of MA (p = 0.709). MA at T4 was not statistically significantly different between patients with pseudodrusen at baseline (p = 0.497).

CONCLUSIONS

Intravitreal anti-VEGF injections with PRN regimen in MNV type 3 showed functional and anatomical benefits. Variations of retinal thickness and choroidal thickness during treatment were related to MA modification over time.

CHARACTERISTICS PREDICTIVE OF FELLOW-EYE GEOGRAPHIC ATROPHY WITHOUT NEOVASCULARIZATION IN UNILATERAL TYPE 3 MACULAR NEOVASCULARIZATION

PURPOSE

To evaluate the predictive characteristics of fellow-eye geographic atrophy (GA) without neovascularization in patients with unilateral Type 3 macular neovascularization.

METHODS

This retrospective study included 84 patients who were diagnosed with unilateral Type 3 macular neovascularization. Patients who developed fellow-eye neovascularization and those exhibiting GA without neovascularization at the final follow-up were included in the neovascularization and GA groups, respectively. The patient demographics and baseline fellow-eye characteristics were compared between the two groups.

RESULTS

The mean follow-up period was 40.5 ± 11.5 months after diagnosis. Patients included in the GA group (n = 28) were significantly older (mean 77.4 ± 5.2 years vs. 74.2 ± 5.8 years, P = 0.016), had significantly thinner subfoveal choroidal thickness (mean 109.4 ± 36.8 µ m vs. 173.1 ± 77.6 µ m, P < 0.001), and had a significantly higher incidence of baseline GA (39.3% vs. 16.1%, P = 0.019) than those included in the neovascularization group (n = 56). In the multivariate analysis, subfoveal choroidal thickness showed a close negative association with the risk of GA rather than neovascularization ( P = 0.004, β = 0.982, 95% confidence interval = 0.970-0.994).

CONCLUSION

In patients with unilateral Type 3 macular neovascularization, older age, the presence of GA, and a thin choroid in the fellow eye were found to be indicative of a higher probability of progression toward fellow-eye GA instead of neovascularization may be potential candidates for future complement inhibitor treatments targeting fellow-eye GA.

Distinct Pathways of Macular Atrophy in Type 3 Macular Neovascularization Associated With AMD

Purpose

To explore the occurrence of macular atrophy (MA) in eyes with age-related macular degeneration (AMD)-associated Type 3 macular neovascularization (MNV) treated with anti-vascular endothelial growth factor (anti-VEGF) therapy. Importantly, we aimed at describing the existence of separate pathways leading to MA.

Methods

We analyzed 41 participants (41 eyes) with treatment-naïve Type 3 MNV who were followed up for a duration of 12 months after beginning the anti-VEGF therapy. At the one-year follow-up visit, optical coherence tomography (OCT) scans were reviewed for the presence of MA. MA regions of interest (ROIs) were selected and traced back to their original dominant baseline lesion (i.e., precursor) through previous serially captured OCT scans. Baseline lesions included precursors associated with the development and exudation of MNV and causes external to the neovascularization itself.

Results

At the one-year follow-up visit, MA was graded to be present in 38 (92.7%) out of 41 eyes. These 78 MA ROIs were divided into two subgroups according to the precursor lesion, yielding a group of 53 MA lesions with precursors associated with the development and exudation of MNV (i.e., MA caused by physical harm from Type 3 neovessels, collapse of a serous pigment epithelium detachment, and fibrosis) and 25 MA regions with precursors external to the neovascularization itself (i.e., MA caused by drusen or subretinal drusenoid deposits).

Conclusions

Eyes with Type 3 MNV are commonly complicated by MA and precursors of MA include causes associated with the development and exudation of MNV, as well as lesions unrelated to the neovascularization process itself.

Optical coherence tomography biomarkers in early and intermediate age-related macular degeneration: A clinical guide

Advanced forms of age-related macular degeneration (AMD), characterised by atrophic and neovascular changes, are a leading cause of vision loss in the elderly population worldwide. Prior to the development of advanced AMD, a myriad of risk factors from the early and intermediate stages of AMD have been published in the scientific literature over the last years. The ability to precisely recognise structural and anatomical changes in the ageing macula, altogether with the understanding of the individual risk implications of each one of them is key for an accurate and personalised diagnostic assessment. The present review aims to summarise updated evidence of the relative risk conferred by diverse macular signs, commonly seen on optical coherence tomography, in terms of progression to geographic atrophy or macular neovascularization. This information may also serve as a basis for tailored follow-up monitoring visits.

Risk factors for development of hyper-reflective foci overlying drusen in eyes with intermediate age-related macular degeneration

AIMS

The aim of this study is to assess baseline characteristics of drusen preceding the development of intraretinal hyper-reflective foci (IHRF) in eyes with intermediate age-related macular degeneration (AMD).

METHODS

In this retrospective case-control study, longitudinal optical coherence tomography (OCT) volume data from eyes with intermediate AMD in a retina clinic population were screened. All drusen that developed overlying IHRF were marked. A random number generator was used to select for further grading three drusen that did not develop IHRF.

RESULTS

Ninety eyes (from 72 patients), including 140 drusen with overlying IHRF and 270 IHRF- drusen, were analysed. Greater drusen height, basal drusen width and overlying ellipsoid zone (EZ) and external limiting membrane disruption were associated with a significantly greater risk for IHRF development (p≤0.001). Regression analysis revealed EZ disruption increased these odds by 4.1 (p≤0.001). Each 10-µm increase in drusen height and width increased the odds by 34% (p≤0.001) and 3% (p: 0.005), respectively. Each 100-µm increase in distance from the fovea decreased the odds by 10% (p: 0.013).

CONCLUSIONS

The presence of overlying EZ disruption and a greater drusen height substantially increased the risk for IHRF development, whereas drusen further from the fovea indicated reduced risk. Given the importance of IHRF as a biomarker for AMD progression, these findings may be of value in defining patient populations for future early intervention trials.

Assessment of intraretinal hyperreflective foci using multimodal imaging in eyes with age-related macular degeneration

PURPOSE

This study aimed to investigate the correspondence between intraretinal hyperreflective foci (IHRF) identified on optical coherence tomography (OCT) B-scans with hyperpigmentation on colour fundus photography (CFP) or hyperreflectivity on infrared reflectance (IR) images in eyes with age-related macular degeneration (AMD).

METHODS

Flash CFP, IR images and OCT B-scans obtained at the same visit were evaluated. Individual IHRF identified on OCT B-scans were assessed for the qualitative presence or absence of a hypotransmission tail into the choroid. The corresponding IR image obtained at the time of OCT acquisition was analysed for the presence or absence of hyperreflectivity in this region. The IR images were manually registered to the CFP image, and CFP images were inspected for the presence or absence of hyperpigmentation at the location of IHRF.

RESULTS

From 122 eyes, a total of 494 IHRF were evaluated. For the primary analysis of qualitative presence or absence of hyperpigmentation on CFP and hyperreflectivity on IR at the locations corresponding to IHRF on OCT, 301 (61.0%) of the IHRFs demonstrated evidence of hyperpigmentation on CFP, while only 115 (23.3%) showed evidence of hyperreflectivity on IR. The qualitative determination of the presence or absence of an abnormality on CFP or IR were significantly different (p < 0.0001). 327 (66.2%) of the IHRF showed hypotransmission, and 80.4% of these IHRF showed hyperpigmentation on CFP, though only 23.9% (p < 0.0001) demonstrated hyperreflectivity on IR.

CONCLUSIONS

Less than two-thirds of IHRF evident on OCT manifest as hyperpigmentation on colour photos, though IHRF with posterior shadowing are more likely to be evident as pigment. IR imaging appears to be even more poorly sensitive for visualizing IHRF.

FROM DRUSEN TO TYPE 3 MACULAR NEOVASCULARIZATION

PURPOSE

To investigate the imaging features preceding the occurrence of type 3 (T3) macular neovascularization (MNV) using tracked spectral-domain optical coherence tomography.

METHOD

From a cohort of eyes with T3 MNV and ≥ 12 months of previously tracked spectral-domain optical coherence tomography, T3 lesions that developed above soft drusen were selected for optical coherence tomography analysis. Retinal imaging findings at the location where type T3 MNV occurred were analyzed at each follow-up until the onset of T3 MNV. The following optical coherence tomography parameters were assessed: drusen size (height and width), outer nuclear layer/Henle fiber layer thickness at the drusen apex, and the presence of intraretinal hyperreflective foci, retinal pigment epithelium disruption, incomplete retinal pigment epithelium and outer retina atrophy, and complete retinal pigment epithelium and outer retina atrophy.

RESULTS

From a cohort of 31 eyes with T3 MNV, T3 lesions developed above soft drusen in 20 eyes (64.5%). Drusen showed progressive growth ( P < 0.001) associated with outer nuclear layer/Henle fiber ( P < 0.001) thinning before T3 MNV. The following optical coherence tomography features were identified preceding the occurrence of T3 MNV, typically at the apex of the drusenoid lesion: disruption of the external limiting membrane/ellipsoid zone and/or the retinal pigment epithelium, hyperreflective foci, and incomplete retinal pigment epithelium and outer retina atrophy/complete retinal pigment epithelium and outer retina atrophy.

CONCLUSION

The results demonstrate specific anatomic alterations preceding the occurrence of T3 MNV that most commonly originates above soft drusen. Drusen growth, reduced outer nuclear layer/Henle fiber thickness, and retinal pigment epithelium atrophy at the drusen apex precede the development of T3 MNV. Identifying these optical coherence tomography features should warrant close monitoring for identification of T3 MNV, which can benefit from prompt intravitreal anti-vascular endothelial growth factor therapy.

Current Perspectives on Type 3 Macular Neovascularization due to Age-Related Macular Degeneration

BACKGROUND

The aim of this review was to systematically summarize the current knowledge on type 3 macular neovascularization (MNV3) in age-related macular degeneration (AMD).

SUMMARY

Recent histopathologic and multimodal imaging findings led to the consensus definition of the new term "type 3 macular neovascularization" in AMD. MNV3 originates in the deep vascular plexus as a neovascular process without connection with the retinal pigment epithelium in the initial stages. This type has numerous clinical and pathomorphologic features that separate it from the other two types of MNV in AMD. Besides, its frequency appears to be higher than previously thought. In optical coherence tomography (OCT), MNV3 can be classified into stages 1-3. Hyperreflective foci in the outer retina possibly represent a precursor lesion. In addition, MNV3 is characterized by a strong association with reticular pseudodrusen, a high rate of bilaterality, close associations with advanced age and arterial hypertension, decreased choroidal thickness, and decreased choriocapillaris flow signals. Data from latest anti-vascular endothelial growth factor studies in MNV3 suggest that the OCT biomarkers in intraretinal and subretinal fluids should be interpreted differently than in the other types. Additionally, data from MNV3 eyes should be analyzed separately, allowing optimal type-specific treatment strategies in the future.

KEY MESSAGES

This review highlights the need for accurate characterization of neovascular AMD lesions and an MNV type-specific approach, particularly for MNV3.

Lesion area progression in eyes with neovascular age-related macular degeneration treated using a proactive or a reactive regimen

BACKGROUND

To compare the change in lesion area over 4 years of follow-up in eyes with neovascular age-related macular degeneration (nAMD) treated with anti-vascular endothelial growth factor (VEGF) agents using either a proactive or a reactive regimen in routine clinical practice.

METHODS

This was a multicentre, retrospective comparative study. Totally, 202 treatment-naïve nAMD eyes (183 patients) received anti-VEGF therapy according to a proactive (n = 105) or reactive (n = 97) regimen. Eyes were included if they had received anti-VEGF injections for a period of at least 4 years and had baseline fluorescein angiography and annual optical coherence tomography (OCT) imaging. Two masked graders independently delineated the lesion's margins from serial OCT images and growth rates were calculated.

RESULTS

At baseline, the mean [SD] lesion area was 7.24 [5.6] mm2 in the proactive group and 6.33 [4.8] mm2 in the reactive group respectively (p = 0.22). After four years of treatment, the mean [SD] lesion area in the proactive group was 5.16 [4.5] mm2 showing a significant reduction compared to the baseline (p < 0.001). By contrast, the mean [SD] lesion area kept expanding in the reactive group during the follow-up and was 9.24 [6.0] mm2 at four years (p < 0.001). The lesion area at 4 years was significantly influenced by treatment regimen, baseline lesion area, and proportion of visits with active lesions.

CONCLUSIONS

Eyes treated using a reactive strategy had an increased lesion area and worse visual outcomes at 4 years. By contrast, the proactive regimen was associated with fewer recurrences of active disease, shrinkage of the lesion area, and better vision at four years.

PIGMENT EPITHELIAL DETACHMENT THICKNESS AND VARIABILITY AFFECTS VISUAL OUTCOMES IN PATIENTS WITH NEOVASCULAR AGE-RELATED MACULAR DEGENERATION

PURPOSE

To evaluate the impact of pigment epithelial detachment (PED) thickness (i.e., height) and thickness variability on best-corrected visual acuity outcomes in patients with neovascular age-related macular degeneration in the Phase 3 HAWK and HARRIER trials.

METHODS

Optical coherence tomography images from the pooled brolucizumab 6 mg and aflibercept 2 mg arms were analyzed for the maximum PED thickness across the macula at baseline through to week 96. Best-corrected visual acuity outcomes were compared in patients with different PED thickness and variability cut-off thresholds.

RESULTS

Greater PED thickness at baseline or at week 12 was associated with lower mean best-corrected visual acuity gain from baseline to week 96 (baseline PED ≥200 µ m: +4.6 letters; <200 µ m: +7.0 letters; week 12 PED ≥100 µ m: +5.6 letters; <100 µ m: +6.6 letters). Eyes with the largest PED thickness variability from week 12 through week 96 gained fewer letters from baseline at week 96 (≥33 µ m: +3.3 letters; <9 µ m: +6.2 letters). Furthermore, increased PED thickness at week 48 was associated with higher prevalence of intraretinal and subretinal fluid.

CONCLUSION

In this treatment-agnostic analysis, greater PED thickness and PED thickness variability were associated with poorer visual outcomes in patients with neovascular age-related macular degeneration and greater neovascular activity.

Preliminary analysis of predicting the first recurrence in patients with neovascular age-related macular degeneration using deep learning

BACKGROUND

To predict, using deep learning, the first recurrence in patients with neovascular age-related macular degeneration (nAMD) after three monthly loading injections of intravitreal anti-vascular endothelial growth factor (anti-VEGF).

METHODS

Optical coherence tomography (OCT) images were obtained at baseline and after the loading phase. The first recurrence was defined as the initial appearance of a new retinal hemorrhage or intra/subretinal fluid accumulation after the initial resolution of exudative changes after three loading injections. Standard U-Net architecture was used to identify the three retinal fluid compartments, which include pigment epithelial detachment, subretinal fluid, and intraretinal fluid. To predict the first recurrence of nAMD, classification learning was conducted to determine whether the first recurrence occurred within three months after the loading phase. The recurrence classification architecture was built using ResNet50. The model with retinal regions of interest of the entire region and fluid region on OCT at baseline and after the loading phase is presented.

RESULTS

A total of 1,444 eyes of 1,302 patients were included. The mean duration until the first recurrence after the loading phase was 8.20 ± 15.56 months. The recurrence classification system revealed that the model with the fluid region of OCT after the loading phase provided the highest classification performance, with an area under the receiver operating characteristic curve (AUC) of 0.725 ± 0.012. Heatmap analysis revealed that three pathological fluids, subsided choroidal neovascularization lesions, and hyperreflective foci were important areas for the first recurrence.

CONCLUSIONS

The deep learning algorithm allowed for the prediction of the first recurrence for three months after the loading phase with adequate feasibility. An automated prediction system may assist in establishing patient-specific treatment plans and the provision of individualized medical care for patients with nAMD.

Pushing Retinal Imaging Forward: Innovations and Their Clinical Meaning - The 2022 Ophthalmologica Lecture

Retinal imaging has greatly expanded our understanding of various pathological conditions. This article presents a summary of the key points covered during the 2022 Ophthalmologica Lecture held at the Euretina Congress in Hamburg. The first part of the article focuses on the use of optical coherence tomography angiography to examine and comprehend the choroid in age-related macular degeneration (AMD). Subsequently, we delve into the discussion of the "postreceptor neuronal loss" theory in AMD, which was studied using en face structural optical coherence tomography (OCT). Following that, we explore pertinent findings obtained through cross-sectional OCT in retinal and optic nerve diseases, such as AMD, diabetic macular edema, pathologic myopia, central serous chorioretinopathy, and Leber's hereditary optic neuropathy.

INCIDENCE AND TIMING OF PIGMENT EPITHELIAL DETACHMENT AND SUBRETINAL FLUID DEVELOPMENT IN TYPE 3 MACULAR NEOVASCULARIZATION ASSOCIATED WITH AGE-RELATED MACULAR DEGENERATION

PURPOSE

To evaluate the incidence and timing of pigment epithelial detachment (PED) and subretinal fluid (SRF) development in type 3 macular neovascularization.

METHODS

This retrospective study included 84 patients who were diagnosed with treatment-naïve type 3 macular neovascularization who did not show SRF at diagnosis. All patients were initially treated with three loading injections of ranibizumab or aflibercept. After the initial loading injections, as-needed regimen was performed for retreatment. The development of either PED or SRF was identified. The incidence and timing of PED development in patients without PED at diagnosis and that of SRF development in patients with PED at diagnosis were evaluated.

RESULTS

The mean follow-up period was 41.3 ± 20.7 months after diagnosis. Among the 32 patients without serous PED at diagnosis, PED developed in 20 (62.5%) at a mean of 10.9 ± 5.1 months after diagnosis. PED development was noted within 12 months in 15 patients (46.8%; 75.0% among the PED development cases). In 52 patients with serous PED and without SRF at diagnosis, 15 developed SRF (28.8%) at a mean of 11.2 ± 6.4 months after diagnosis. SRF development was noted within 12 months in nine patients (17.3%; 66.6% among the SRF development cases).

CONCLUSION

PED and SRF developed in a substantial proportion of patients with type 3 macular neovascularization. The average period of development of these pathologic findings was within 12 months of diagnosis, suggesting the need for active treatment during the early treatment period to improve treatment outcomes.

Two potentially distinct pathways to geographic atrophy in age-related macular degeneration characterized by quantitative fundus autofluorescence

BACKGROUND/AIMS

To demonstrate two distinct pathways to geographic atrophy (GA) that originate from soft drusen/ pigment epithelial detachments (PEDs) and subretinal drusenoid deposits (SDDs), respectively, and are characterized by their final quantitative autofluorescence (qAF) levels.

METHODS

23 eyes of 18 patients with GA underwent spectral-domain optical coherence tomography (SD-OCT) and qAF imaging on the qAF-ready Heidelberg Spectralis. 52 GA Regions-of-interest (ROIs), or clusters of adjacent lesions, were selected, and the ROIs were divided into groups by the dominant iAMD precursors on prior serial tracked SD-OCT scans. Mean qAF values and structural SD-OCT findings of groups were compared.

RESULTS

Group 1 lesions (soft drusen/PED precursors, 18/52) were isolated, with lower mean qAF (35.88 ± 12.75 units); group 3 lesions (SDD precursors, 12/52) were multilobular, with significantly higher mean qAF (71.62 ± 12.12 units, p < 0.05). Group 2 lesions, (mixed precursors, 22/52) had intermediate mean qAF (58.13 ± 67.92 units). Significantly greater prevalence of split RPE/ Bruch's membrane complex in SDD-associated GA, suggesting basal laminar deposit (BLamD), than in drusen-associated lesions was the major structural difference.

CONCLUSION

Quantitative autofluorescence (qAF) of GA lesions may reflect two distinct pathogenic pathways and structural outcomes, originating from soft drusen/PED and subretinal drusenoid deposits (SDDs), with the final qAF values lower or higher, respectively. Basal laminar deposit specifically in and adjacent to SDD-associated lesions may account for their greater autofluorescence. The potential importance of this paradigm is that it could direct, simplify and facilitate research on geographic atrophy by dividing the disease into two components that may be studied separately.

Early Optical Coherence Tomography Biomarkers for Selected Retinal Diseases-A Review

Optical coherence tomography (OCT) is a non-invasive, easily accessible imaging technique that enables diagnosing several retinal diseases at various stages of development. This review discusses early OCT findings as non-invasive imaging biomarkers for predicting the future development of selected retinal diseases, with emphasis on age-related macular degeneration, macular telangiectasia, and drug-induced maculopathies. Practitioners, by being able to predict the development of many conditions and start treatment at the earliest stage, may thus achieve better treatment outcomes.

Optical Coherence Tomography Biomarkers for Conversion to Exudative Neovascular Age-related Macular Degeneration

PURPOSE

To identify optical coherence tomography (OCT) biomarkers, including thin and thick double-layer sign (DLS) for the progression from intermediate AMD (iAMD) to exudative macular neovascularization (MNV) over 24 months.

DESIGN

Retrospective cohort study.

METHODS

Setting: Retina consultants of Texas.

PATIENT POPULATION

458 eyes of 458 subjects with iAMD in at least 1 eye with 24 months of follow-up data.

MAIN OUTCOMES MEASURES

The following biomarkers were assessed at baseline: high central drusen volume (≥0.03 mm³), intraretinal hyper-reflective foci (IHRF), subretinal drusenoid deposits, hyporeflective drusen cores, thick DLS, thin DLS, and central choroidal thickness. A binary logistic regression was computed to investigate the association between baseline OCT covariates and the conversion to exudative MNV within 24 months. In addition, fellow eye status was also included in the model.

RESULTS

During follow-up, 18.1% (83 of 458) of eyes with iAMD progressed to exudative MNV. Thick DLS, IHRF, and fellow eye exudative MNV were found to be independent predictors for the development of exudative MNV within 2 years. The baseline frequencies, odds ratios, 95% confidence intervals, and P values for these biomarkers were as follows: thick DLS (9.6%, 4.339, 2.178-8.644; P < .001), IHRF (36.0%, 2.340, 1.396-3.922; P = 0.001), and fellow eye exudative MNV (35.8%, 1.694, 1.012-2.837; P = .045).

CONCLUSIONS

Thick DLS, IHRF, and fellow eye exudative MNV were associated with an increased risk of progression from iAMD to exudative MNV. These biomarkers, which are readily identified by the review of OCT volume scans, may aid in risk prognostication for patients and for identifying patients for early intervention trials.

Nascent Geographic Atrophy as a Predictor of Type 3 Macular Neovascularization Development

PURPOSE

To investigate the association of nascent geographic atrophy (GA) preceding the development of exudative type 3 macular neovascularization (MNV) in patients with age-related macular degeneration (AMD).

DESIGN

Retrospective longitudinal study.

PARTICIPANTS

Patients with AMD diagnosed with treatment-naive exudative type 3 MNV in 1 or both eyes were evaluated. Inclusion criteria included serial tracked structural OCT examinations for ≥ 2 years before the detection of exudative type 3 MNV.

METHODS

Clinical characteristics and retinal imaging, including structural OCT at baseline and at each follow-up examination, were analyzed. Eyes showing the presence of nascent GA during the follow-up were selected for analysis of prevalence, and clinical characteristics at the site of subsequent type 3 MNV development.

MAIN OUTCOME MEASURES

Description of the prevalence and clinical characteristics of nascent GA at the site of subsequent type 3 MNV development.

RESULTS

Overall, 97 eyes affected by type 3 MNV meeting inclusion criteria were analyzed. Of 97 eyes (71 patients), 22 eyes of 21 patients (mean age 82 ± 9 years) showed nascent GA preceding exudative type 3 MNV. The observed prevalence of nascent GA preceding exudative type 3 MNV was 22.7% (95% confidence interval, 14.4%-31.0%). Exudative type 3 MNV developed a mean of 9 ± 6 months after detection of nascent GA. The presence of reticular pseudodrusen in the study eye did not significantly influence the timing of exudative type 3 MNV development after the observation of nascent GA (P > 0.1 in all analyses). Reduced best-corrected visual acuity was recorded at the exudative type 3 stage in comparison with the nascent GA stage (P = 0.003).

CONCLUSIONS

As nascent GA may precede the development of exudative type 3 MNV, the detection of nascent GA in eyes with AMD may warrant closer surveillance to identify early exudative type 3 MNV warranting treatment.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Difference in characteristics and lesion reactivation between type 3 macular neovascularization with and without subretinal fluid at baseline

PURPOSE

To compare the characteristics and incidence rates of lesion reactivation after anti-vascular endothelial growth factor (VEGF) treatment in type 3 macular neovascularization (MNV) with and without subretinal fluid (SRF) at baseline.

METHODS

This retrospective study included 95 patients diagnosed with type 3 MNV. After the initial loading injections, re-treatment was performed when lesion reactivation occurred defined as the re-accumulation of subretinal or intraretinal fluid or the new development of a retinal/subretinal hemorrhage. The differences in the baseline characteristics and the incidence rates of lesion reactivation were compared between patients with SRF (SRF group, n = 42) and those without SRF (non-SRF group, n = 53).

RESULTS

At diagnosis, the mean visual acuity was worse (0.68 ± 0.41 vs 0.50 ± 0.36; P = 0.032), mean central retinal thickness was greater (515.4 ± 145.9 μm vs 383.8 ± 105.5 μm; P < 0.001), and the incidence of focal retinal hemorrhages was higher (90.5% vs 66.0%; P = 0.005) in the SRF group than in the non-SRF group. In the SRF group, the first lesion reactivation was noted in 89.7% at a mean of 5.8 ± 4.4 months after the third injection. In the non-SRF group, the first lesion reactivation was noted in 70.6% at a mean of 6.1 ± 3.8 months. There was a significant difference in lesion reactivation between the two groups (P = 0.019).

CONCLUSIONS

The difference in the baseline characteristics and incidence of lesion reactivation between type 3 MNV with and without SRF suggests that the presence of SRF may be indicative of more advanced disease with a high risk of visual deterioration. This result also suggests the need for more active treatment to preserve vision in patients with SRF.

Effect of OCT B-Scan Density on Sensitivity for Detection of Intraretinal Hyperreflective Foci in Eyes with Age-Related Macular Degeneration

PURPOSE

To evaluate the impact of reducing the density of B-scans in an optical coherence tomography (OCT) volume on the sensitivity for detecting intraretinal hyperreflective foci (IHRF) in eyes with intermediate age-related macular degeneration (AMD).

METHODS

A total of 165 eyes with intermediate AMD and IHRF were evaluated in this retrospective analysis. For each case, Cirrus HD-OCT volumes were imported into the reading center 3 D-OCTOR software. The number of IHRF cases was assessed based on all 128 B-scans (spaced 47 μm apart), using a categorical scale (graded as 1-4, 5-9, 10-14, 15-19, and >20). Additionally, the B-scan densities in the volume were lowered to 64 B-scans (spaced 94 μm apart), 43 B-scans (spaced 140 μm apart), and 32 B-scans (spaced 188 μm apart). The number of eyes with any IHRF and the numerical category of IHRF in the eye were used to compare the sensitivity at each reduced B-scan density against the reference 128 B-scan volume.

RESULTS

In the primary analysis for the qualitative presence or absence of any IHRF, the sensitivity decreased to 98.2% (p = .32) with 64 B-scans, 92.7% (p = .001) with 43 B-scans, and 75.2% (p = .001) with 32 B-scans, compared with the 128 B-scan reference. With regard to the number of IHRF per eye, there was a significant difference (with a lower level chosen on the scale) when the B-scan density was reduced to 43 or 32 B-scans (p = .002 and p < .001, respectively).

CONCLUSION

Increasing the inter-B-scan spacing from 47 to 188 microns significantly reduced the ability to accurately determine whether IHRF were present in an eye. An increase in inter-B-scan spacing to 140 microns was associated with a significant misclassification of the IHRF quantity. These findings may be relevant in the design of OCT scanning protocols for studies utilizing these biomarkers for AMD progression.

Genetic Association Analysis of Anti-VEGF Treatment Response in Neovascular Age-Related Macular Degeneration

Anti-VEGF treatment for neovascular age-related macular degeneration (nAMD) has been FDA-approved in 2004, and since then has helped tens of thousands of patients worldwide to preserve vision. Still, treatment responses vary widely, emphasizing the need for genetic biomarkers to robustly separate responders from non-responders. Here, we report the findings of an observational study compromising 179 treatment-naïve nAMD patients and their reaction to treatment after three monthly doses of anti-VEGF antibodies. We show that established criteria of treatment response such as visual acuity and central retinal thickness successfully divides our cohort into 128 responders and 51 non-responders. Nevertheless, retinal thickness around the fovea revealed significant reaction to treatment even in the formally categorized non-responders. To elucidate genetic effects underlying our criteria, we conducted an undirected genome-wide association study followed by a directed replication study of 30 previously reported genetic variants. Remarkably, both approaches failed to result in significant findings, suggesting study-specific effects were confounding the present and previous discovery studies. Of note, all studies so far are greatly underpowered, hampering interpretation of genetic findings. In consequence, we highlight the need for an extensive phenotyping study with sample sizes exceeding at least 15,000 to reliably assess anti-VEGF treatment responses in nAMD.

Macular neovascularization lesion type and vision outcomes in neovascular age-related macular degeneration: post hoc analysis of HARBOR

Purpose

To characterize relationships between Consensus on Neovascular Age-Related Macular Degeneration Nomenclature (CONAN) Study Group classifications of macular neovascularization (MNV) and visual responses to ranibizumab in patients with neovascular age-related macular degeneration (nAMD).

Methods

This was a post hoc analysis of the phase 3 HARBOR trial of ranibizumab in nAMD. Analyses included ranibizumab-treated eyes with baseline multimodal imaging data; baseline MNV; subretinal and/or intraretinal fluid at screening, baseline, or week 1; and spectral-domain optical coherence tomography images through month 24 (n = 700). Mean best-corrected visual acuity (BCVA) over time and mean BCVA change at months 12 and 24 were compared between eyes with type 1, type 2/mixed type 1 and 2 (type 2/M), and any type 3 MNV at baseline.

Results

At baseline, 263 (37.6%), 287 (41.0%), and 150 (21.4%) eyes had type 1, type 2/M, and any type 3 lesions, respectively. Type 1 eyes had the best mean BCVA at baseline (59.0 [95% CI: 57.7–60.3] letters) and month 24 (67.7 [65.8–69.6] letters), whereas type 2/M eyes had the worst (50.0 [48.6–51.4] letters and 60.8 [58.7–62.9] letters, respectively). Mean BCVA gains at month 24 were most pronounced for type 2/M eyes (10.8 [8.9–12.7] letters) and similar for type 1 (8.7 [6.9–10.5] letters) and any type 3 eyes (8.3 [6.3–10.3] letters).

Conclusion

Differences in BCVA outcomes between CONAN lesion type subgroups support the use of an anatomic classification system to characterize MNV and prognosticate visual responses to anti-vascular endothelial growth factor therapy for nAMD.

Trial registration

ClinicalTrials.gov identifier: NCT00891735. Date of registration: April 29, 2009.

Difference Between the Incidence of Retinal Fluid Subtypes and Their Association with Visual Outcomes According to the Types of Macular Neovascularization in a Korean Population

Purpose: To investigate differences in the incidence of retinal fluid subtypes among different subtypes of macular neovascularization (MNV) and evaluate the influence of the presence of retinal fluid subtypes on visual outcome in each subtype of MNV. Methods: This retrospective study included 248 patients (248 eyes) diagnosed with treatment-naive neovascular age-related macular degeneration and polypoidal choroidal vasculopathy (PCV). The incidence of retinal fluid subtypes at diagnosis and during the 24-month follow-up was compared among the different subtypes of MNV. In addition, visual acuity was compared between patients with and without the retinal fluid subtypes. Results: At diagnosis, there was a significant difference in the incidence of subretinal fluid (SRF), intraretinal fluid (IRF), and subretinal pigment epithelial fluid among type 1 MNV, type 2 MNV, type 3 MNV, and PCV (P < 0.001). The incidence of SRF (P < 0.001) during follow-up also differed among the 4 groups. In patients with type 1 MNV and IRF, the visual acuity at diagnosis (P = 0.004) and at 24 months (P < 0.001) were significantly worse. However, the presence of SRF was not associated with poor visual acuity. In type 3 MNV, there was no significant difference in visual acuity between patients with and without SRF/IRF. Conclusion: The results of this study indicate that the clinical significance of retinal fluid subtypes may differ in different subtypes of MNV, suggesting the need for analysis in isolation of each MNV subtype in fluid-based prognostication.

Significance of Hyperreflective Foci as an Optical Coherence Tomography Biomarker in Retinal Diseases: Characterization and Clinical Implications

Hyperreflective foci (HRF) is a term coined to depict hyperreflective dots or roundish lesions within retinal layers visualized through optical coherence tomography (OCT). Histopathological correlates of HRF are not univocal, spacing from migrating retinal pigment epithelium cells, lipid-laden macrophages, microglial cells, and extravasated proteinaceous or lipid material. Despite this, HRF can be considered OCT biomarkers for disease progression, treatment response, and prognosis in several retinal diseases, including diabetic macular edema, age-related macular degeneration (AMD), retinal vascular occlusions, and inherited retinal dystrophies. The structural features and topographic location of HRF guide the interpretation of their significance in different pathological conditions. The presence of HRF less than 30 μm with reflectivity comparable to the retinal nerve fiber layer in the absence of posterior shadowing in diabetic macular edema indicates an inflammatory phenotype with a better response to steroidal treatment. In AMD, HRF overlying drusen are associated with the development of macular neovascularization, while parafoveal drusen and HRF predispose to macular atrophy. Thus, HRF can be considered a key biomarker in several common retinal diseases. Their recognition and critical interpretation via multimodal imaging are vital to support clinical strategies and management.

Impact of macular fluid features on outcomes of anti-vascular endothelial growth factor treatment for type 3 macular neovascularization

We evaluated the impact of macular fluid features on visual and anatomical outcomes in type 3 macular neovascularization (MNV) patients treated with anti-vascular endothelial growth factor (VEGF). We retrospectively enrolled 89 eyes with type 3 MNV with at least 12 months of follow-up. All patients were treatment-naïve and received a monthly loading injection of anti-VEGF for three months, followed by further injections as required. The association of baseline macular morphology, including intraretinal fluid (IRF) and subretinal fluid (SRF), with visual and anatomical outcomes was analyzed. At baseline, IRF was present in all enrolled patients (100%), and SRF was present in 43.8% (39/89) of them. After 12 months of treatment, no significant difference was found in terms of best-corrected visual acuity (BCVA) and changes in central foveal thickness between the eyes with (39) and without (50) SRF at baseline. In addition, the proportion of improved or worsened (gain or loss of more than three lines in the BCVA) visual acuity at 12 months was not significantly different among the groups. Incidence of macular atrophy during the treatment showed no difference between the groups, regardless of the presence of SRF. In conclusion, the macular fluid morphology, specifically SRF, in type 3 MNV showed no significant correlation with visual and anatomical outcomes during anti-VEGF treatment.

Clinical Pathological Features and Current Animal Models of Type 3 Macular Neovascularization

Type 3 macular neovascularization (MNV3), or retinal angiomatous proliferation (RAP), is a distinct type of neovascular age-related macular degeneration (AMD), which is a leading cause of vision loss in older persons. During the past decade, systematic investigation into the clinical, multimodal imaging, and histopathological features and therapeutic outcomes has provided important new insight into this disease. These studies favor the retinal origin of MNV3 and suggest the involvement of retinal hypoxia, inflammation, von Hippel–Lindau (VHL)–hypoxia-inducible factor (HIF)–vascular endothelial growth factor (VEGF) pathway, and multiple cell types in the development and progression of MNV3. Several mouse models, including the recently built Rb/p107/Vhl triple knockout mouse model by our group, have induced many of the histological features of MNV3 and provided much insight into the underlying pathological mechanisms. These models have revealed the roles of retinal hypoxia, inflammation, lipid metabolism, VHL/HIF pathway, and retinoblastoma tumor suppressor (Rb)–E2F cell cycle pathway in the development of MNV3. This article will summarize the clinical, multimodal imaging, and pathological features of MNV3 and the diversity of animal models that exist for MNV3, as well as their strengths and limitations.

THE RAP STUDY, REPORT TWO: The Regional Distribution of Macular Neovascularization Type 3, a Novel Insight Into Its Etiology

PURPOSE

To explore the regional distribution of macular neovascularization type 3 (MNV3).

METHODS

Seventy-eight eyes of 78 patients were reviewed. We defined the location of each lesion after applying a modified ETDRS grid and the incidence of simultaneous MNV1 or 2. Also, we investigated the distribution of MNV3 at the outline of the foveal avascular zone and when the diameter of foveal avascular zone was less than 325 µm.

RESULTS

The distribution of MNV3 was 4 lesions (5%) from the center to 500 µm, 72 (92%) from 500 µm to 1500 µm, and 2 (3%) from 1,500 µm to 3000 µm. The distribution in respect of the ETDRS fields was 7 (9%) nasal, 16 (20%) superior, 32 (40%) temporal, and 23 (31%) inferior. No additional MNV1 or 2 were found elsewhere. Most lesions tended to distribute along straight bands radiating from the perifoveal area, mainly in the temporal half (72%). None of the cases had MNV3 at the boundary of the foveal avascular zone. Only five cases had foveal avascular zone diameter of less than 325 µm, the closest lesion was 425 µm away from the center.

CONCLUSION

MNV3 lesions are most likely neither symmetrical nor uniformly distributed. They have a higher affinity to distribute radially in the temporal perifoveal area.

CHORIOCAPILLARIS FLOW IMPAIRMENT IN TYPE 3 MACULAR NEOVASCULARIZATION: A Quantitative Analysis Using Swept-Source Optical Coherence Tomography Angiography

PURPOSE

To quantitatively analyze choriocapillaris alterations using swept-source optical coherence tomography angiography in eyes presenting with Type 3 macular neovascularization (MNV) and to compare these alterations with eyes presenting with intermediate AMD (iAMD).

METHODS

Macular 3 × 3-mm swept-source optical coherence tomography angiography scans were retrospectively analyzed in eyes with Type 3 MNV and in eyes with iAMD. The choriocapillaris en face slabs were extracted from the swept-source optical coherence tomography angiography device after manual segmentation. En face choriocapillaris flow images were compensated with en face choriocapillaris structure images, followed by the Phansalkar local thresholding method using a window radius of 4 and 8 pixels. The percentage of flow deficits (FD%), the number, size, and total area of FDs were computed for comparison. A secondary analysis was performed in the four corners of the image to include equidistant regions in all eyes.

RESULTS

Twenty-six Type 3 MNV eyes of 21 patients and 26 iAMD eyes of 17 patients were included. Compared with iAMD eyes, eyes with Type 3 MNV displayed a higher FD% (41.37% ± 14.74 vs. 19.80% ± 9.63 using radius 4 pixels [P < 0.001]; 45.24% ± 11.9 vs. 26.63% ± 8.96 using radius 8 pixels [P < 0.001]). The average size of FDs was significantly larger in Type 3 MNV eyes compared with iAMD eyes (P < 0.001), whereas the number of FDs was significantly lower in Type 3 MNV compared with iAMD eyes (P < 0.001).

CONCLUSION

Type 3 MNV eyes present with increased choriocapillaris flow impairment compared with iAMD eyes. Reduced choriocapillaris perfusion may contribute to Type 3 MNV development and pathogenesis.

Investigation of the Trend of Selecting Anti-Vascular Endothelial Growth Factor Agents for the Initial Treatment of Neovascular Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy

BACKGROUND: This study aimed to investigate the trend of selecting ranibizumab and aflibercept for the initial treatment of neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV). METHODS: This was a retrospective study that included 460 patients who were diagnosed with treatment-naïve neovascular AMD and PCV and were initially treated with either ranibizumab or aflibercept. The patients were divided into two groups: the ranibizumab group (n = 96) and the aflibercept group (n = 324). The patients’ characteristics and the proportion of the subtypes of macular neovascularization (MNV) were compared between the two groups. RESULTS: Patients in the ranibizumab group were significantly older (mean 74.3 ± 8.4 years) than those in the aflibercept group (mean 70.4 ± 8.8 years; p < 0.001). In the ranibizumab group, the proportions of type 1 or 2 MNV, type 3 MNV, and PCV were 50.0%, 27.1%, and 22.9%, respectively. In the aflibercept group, the proportions were 35.2%, 6.8%, and 58.0%, respectively. There was a significant difference in the proportion of MNV subtypes between the ranibizumab and aflibercept groups (p < 0.001). Ranibizumab was used in 54.2% of patients with type 3 MNVs. However, in patients with PCV, aflibercept was used in 89.5% of patients. CONCLUSIONS: Ranibizumab was preferred as an initial treatment agent in older patients and those with type 3 MNV, whereas aflibercept was highly preferred in patients with PCV. The different characteristics and efficacy of the two agents may have partially contributed to this trend.

The role of quantitative deep capillary plexus in the pathogenesis of type 3 macular neovascularization: an optical coherence tomography angiography study

Purpose

To quantitatively investigate the role of deep capillary plexus (DCP) in patients affected by type 3 macular neovascularization (MNV), compared to patients with reticular pseudodrusen (RPD) eyes and healthy controls, using optical coherence tomography angiography (OCTA).

Methods

In this prospective observational study, a total of seventy-eight eyes of 78 patients were included. Group 1 consisted of 40 eyes of 40 patients with stage 1 of type 3 MNV (22 males, 18 females, mean age 73.7, SD ± 6.60) and group 2 included 38 eyes of 38 patients with RPD (17 males, 21 females, mean age 73.2, SD ± 4.55). The control group included 40 eyes of 40 healthy subjects (20 males, 20 females, mean age 71.4, SD ± 6.36 years). We evaluated the retinal vessel density (VD) of superficial capillary plexus (SCP) and deep capillary plexus (DCP) using OCTA.

Results

Patients with diagnosis of type 3 MNV showed statistically lower values of VD in DCP with respect to controls and to RPD group (p < 0.001), while there were no statistical differences between RPD and control group in macular region. No significant differences in VD of SCP were detected among the three study groups.

Conclusion

OCTA provides a reproducible, non-invasive detailed quantitative analysis of retinal vascular features and changing in early-stage type 3 MNV patients, which allowed to shed the light on the main role of DCP ischemia in the development of type 3 MNV.

LONG-TERM CHANGES IN CHOROIDAL THICKNESS IN EYES WITH TYPE 3 MACULAR NEOVASCULARIZATION

PURPOSE

To evaluate the long-term changes in subfoveal choroidal thickness (SCT) in eyes with Type 3 macular neovascularization that underwent anti-vascular endothelial growth factor therapy.

METHODS

This retrospective study was performed with 47 patients diagnosed with Type 3 macular neovascularization and treated with anti-vascular endothelial growth factor therapy. All the patients initially received three loading injections. The SCT was compared at diagnosis, 3 months, 12 months, and at the final follow-up visit. The velocity of changes in SCT was also compared between each period.

RESULTS

The mean follow-up period was 52.1 ± 11.0 months. The mean SCT was 143.3 ± 51.2 µm at diagnosis, and it had significantly decreased to 128.6 ± 47.4 µm at 3 months (P < 0.001), 123.2 ± 45.7 µm at 12 months (P < 0.001), and 110.0 ± 43.0 µm at the final follow-up (P < 0.001). The mean velocity of the decrease in SCT was 4.9 ± 3.9 µm per month during the first 3 months, 0.6 ± 1.2 µm per month between the 3rd and the 12th months, and 0.3 ± 0.3 µm per month between the 12th month and the final follow-up. The velocity of the decrease was significantly greater during the first 3 months than during the 3rd to 12th month (P < 0.001) and 12th month to final follow-up (P < 0.001) periods. The difference was not significant between the 3rd to 12th month and 12th months to final follow-up (P = 0.836) periods.

CONCLUSION

Subfoveal choroidal thickness continuously decreased over time, with a significant decrease of 23% noted in eyes with Type 3 macular neovascularization. The thickness rapidly decreased during the initial loading phase. Subsequently, a continuous but gradual decrease in the thickness was noted.

Longitudinal assessment of type 3 macular neovascularization using three-dimensional volume-rendering OCTA

OBJECTIVE

To investigate the evolution of treatment-naive type 3 macular neovascularization (MNV) undergoing anti-vascular endothelial growth factor (VEGF) treatment through volume rendered three-dimensional (3D) optical coherence tomography angiography (OCTA).

DESIGN

Retrospective observational study.

PARTICIPANTS

Patients with type 3 MNV and age-related macular degeneration (AMD).

METHODS

Included subjects had three loading injections of an anti-VEGF agent. The OCTA volume data at baseline and follow-up were processed with a previously published algorithm in order to obtain a volume-rendered representation of type 3 MNV. Progressive changes in type 3 lesions were analyzed via 3D OCTA volume rendering.

RESULTS

A total of 14 treatment-naive eyes with type 3 MNV from 11 AMD patients (7 females) were included. At both baseline and follow-up visits, a type 3 MNV complex was identifiable. Each complex was composed of a mean number of 2.5 ± 0.7 vascular branches at baseline and 1.4 ± 0.6 at the follow-up visit (p < 0.0001). The mean changes in central macular thickness and visual acuity were significantly correlated with modifications in the number of type 3 MNV branches (ρ = -0.533, p = 0.049, and ρ = -0.581, and p = 0.040, respectively).

CONCLUSIONS

This study demonstrated that type 3 lesions do not disappear completely after loading treatment, as indicated previously by histopathologic studies. Importantly, quantitative volume changes in type 3 lesions are directly associated with treatment response.

SUBRETINAL DRUSENOID DEPOSIT IN AGE-RELATED MACULAR DEGENERATION: Histologic Insights Into Initiation, Progression to Atrophy, and Imaging

PURPOSE

To clarify the role of subretinal drusenoid deposits (SDD; pseudodrusen) in the progression of age-related macular degeneration through high-resolution histology.

METHODS

In 33 eyes of 32 donors (early age-related macular degeneration, n = 15; geographic atrophy, n = 9; neovascular age-related macular degeneration, n = 7; unremarkable, n = 2), and 2 eyes of 2 donors with in vivo multimodal imaging including optical coherence tomography, examples of SDD contacting photoreceptors were assessed.

RESULTS

Subretinal drusenoid deposits were granular extracellular deposits at the apical retinal pigment epithelium (RPE); the smallest were 4-µm wide. Outer segment (OS) fragments and RPE organelles appeared in some larger deposits. A continuum of photoreceptor degeneration included OS disruption, intrusion into inner segments, and disturbance of neurosensory retina. In a transition to outer retinal atrophy, SDD appeared to shrink, OS disappeared, inner segment shortened, and the outer nuclear layer thinned and became gliotic. Stage 1 SDD on optical coherence tomography correlated with displaced OS. Confluent and disintegrating Stage 2 to 3 SDD on optical coherence tomography and dot pseudodrusen by color fundus photography correlated with confluent deposits and ectopic RPE.

CONCLUSION

Subretinal drusenoid deposits may start at the RPE as granular, extracellular deposits. Photoreceptor OS, RPE organelles, and cell bodies may appear in some advanced deposits. A progression to atrophy associated with deposit diminution was confirmed. Findings support a biogenesis hypothesis of outer retinal lipid cycling.

Eyes that Do Not Meet the Eligibility Criteria of Clinical Trials on Age-Related Macular Degeneration: Proportion of the Real-World Patient Population and Reasons for Exclusion

Background

To evaluate the proportion of eyes that do not meet the eligibility criteria of clinical trials on neovascular age-related macular degeneration (AMD) and the reasons for exclusion.

Methods

This retrospective, observational study included 512 eyes of 463 patients diagnosed with treatment-naïve neovascular AMD. The proportion of eyes that did not meet the eligibility criteria of the Vascular Endothelial Growth Factor Trap-Eye: Investigation of Efficacy and Safety in Wet AMD (VIEW) studies were evaluated. The two most common reasons for exclusion were also evaluated in each subtype of neovascular AMD (typical neovascular AMD, polypoidal choroidal vasculopathy (PCV), and type 3 neovascularization).

Results

Among the 512 eyes, 229 (44.7%) did not meet the eligibility criteria. In all the included eyes, the most common reasons for exclusion were good or poor visual acuity (169 eyes, 33.0%), followed by the presence of subretinal hemorrhage (47 eyes, 9.5%). Moreover, good or poor visual acuity was the most common reason for exclusion in all three subtypes of neovascular AMD. The second most common reason was a fovea-involving scar or fibrosis in typical neovascular AMD, subretinal hemorrhage in PCV, and other vascular diseases affecting the retina in type 3 neovascularization.

Conclusions

Among the included cases, 44.7% did not meet the eligibility criteria for VIEW study, suggesting that the conclusion derived from clinical trials may not directly reflect the real-world outcomes. Additionally, the reasons for ineligibility differed among the different subtypes of neovascular AMD.

Assessing the long-term evolution of type 3 neovascularization in age-related macular degeneration using optical coherence tomography angiography

PURPOSE

To analyze the evolution of type 3 neovascularization in eyes with age-related macular degeneration during anti-vascular endothelial growth factor (VEGF) treatment using optical coherence tomography angiography (OCTA) analysis.

METHODS

Forty-one treatment-naïve eyes (37 patients) with type 3 neovascularization were retrospectively included in the study. The growth and morphological changes in the type 3 lesions, which were recorded using OCTA, were compared across time.

RESULTS

The high-flow signal of the lesion on OCTA was significantly increased at the sub-retinal pigment epithelium (RPE) and the choriocapillaris during anti-VEGF treatment. The detection rate of the flow signal in the sub-RPE increased from 50.0% at baseline and 51.2% at 12 months to 65.9% at 24 months (P = 0.013). The flow signal extending into the choriocapillaris was detected in 0% of the eyes at baseline, 9.8% of the eyes at 12 months, and 17.1% of the eyes at 24 months (P = 0.018). The presence of subretinal drusenoid deposits (SDD) was significantly more frequent in the group with extension into the choriocapillaris (100%) than in the group without (61.8%, P = 0.036). For the four eyes with extension into the choroid, the morphological feature of the lesion on en face OCTA evolved into a tangled vascular network, similar to type 1 neovascularization.

CONCLUSION

OCTA analysis revealed that type 3 neovascularization gradually extended downward toward the sub-RPE and choroid during anti-VEGF treatment. The extension of the lesion into the choriocapillaris, suggesting retinal-choroidal anastomosis, was significantly more frequent in eyes with SDD.

Quantitative assessment of choriocapillaris flow deficits in eyes with macular neovascularization

PURPOSE

To investigate choriocapillaris flow deficits (CC FD) in a group of eyes with Type 3 macular neovascularization (MNV) versus a group of eyes with Type 1 and/or 2 MNV versus healthy eyes.

METHODS

In this cross-sectional, retrospective, multicenter, observational study, consecutive patients with Type 3 MNV, Type 1 and/or 2 MNV, and age-matched controls were included. PLEX Elite optical coherence tomography angiography was performed with a 6 × 6 mm scan pattern centered on the fovea. The CC FD was computed in 4 peripheral 1 × 1 mm squares to allow comparison between equidistant regions unaffected by MNV.

RESULTS

Twenty Type 3, 20 Type 1 and/or 2 MNV [13 (65%) Type 1 MNV, 1 (5%) Type 2 MNV, and 6 (30%) mixed Type 1 and 2 MNV], and 20 age-matched controls were included. The mean impairment in the CC in the 4 peripheral squares was 16.07 ± 7.27% in Type 3 MNV eyes, 11.48 ± 5.59% in Type 1/2 MNV eyes, and 9.64 ± 3.59% in controls. Type 3 MNV displayed a statistically significantly higher CC FD compared with both Type 1/2 MNV (P = 0.031) and controls (P < 0.0001). No significant differences were observed between Type 1/2 MNV and controls (P = 0.223).

CONCLUSIONS

CC FD was significantly greater in the peripheral macular regions of eyes with Type 3 MNV compared to eyes with Type 1/2 MNV and normal control eyes. Pathogenic choroidal mechanisms may differ in eyes with different MNV subtypes. Whereas focal CC impairment may drive the development of Type 1/2 MNV, diffuse CC disruption may be more important in eyes with Type 3 MNV.

Difference in treatment burden of neovascular age-related macular degeneration among different types of neovascularization

PURPOSE

To evaluate the difference in the treatment burden among different types of neovascular age-related macular degeneration (AMD).

METHODS

This retrospective, observational study included 431 patients who were diagnosed with neovascular AMD. Patients were divided into three groups: type 1 or 2 neovascularization group (n = 167), type 3 neovascularization group (n = 50), and polypoidal choroidal vasculopathy (PCV) group (n = 214). The number of hospital visits per year and the number of anti-vascular endothelial growth factor (VEGF) injections per year were compared among these groups. Furthermore, the incidence of bilateral involvement during the follow-up period was compared among the groups.

RESULTS

The mean follow-up period was 50.6 ± 11.3 months. The number of hospital visits per year was significantly higher in the type 1 or 2 neovascularization group (mean: 6.1 ± 1.5) and type 3 neovascularization (6.6 ± 1.6) than in the PCV group (6.0 ± 1.5) (P < 0.001). The number of anti-VEGF injections per year was significantly higher in type 3 neovascularization group (3.1 ± 1.7) than in the type 1 or 2 neovascularization group (2.3 ± 1.5) or the PCV group (2.3 ± 1.2) (P = 0.042). There was a significant difference in the incidence of bilateral involvement among patients in type 1 or 2 neovascularization group (20.4%), type 3 neovascularization group (46.0%), and the PCV group (15.4%) (P < 0.001).

CONCLUSIONS

The high frequency of hospital visits and that of anti-VEGF injections in patients with type 3 neovascularization suggests high treatment burden in these patients. The high incidence of bilateral involvement could be one of the primary reasons for high treatment burden in patients with type 3 neovascularization.

SUB-RETINAL PIGMENT EPITHELIUM MULTILAMINAR HYPERREFLECTIVITY AT THE ONSET OF TYPE 3 MACULAR NEOVASCULARIZATION

PURPOSE

To report the prevalence and treatment outcomes of eyes with sub-retinal pigment epithelium (sub-RPE) multilaminar hyperreflectivity at the onset/clinical detection of Type 3 macular neovascularization (MNV) secondary to exudative age-related macular degeneration.

METHODS

Retrospective analysis of consecutive patients diagnosed with Type 3 MNV secondary to age-related macular degeneration was performed. Eyes presenting with sub-RPE multilaminar hyperreflectivity on structural optical coherence tomography at the onset of Type 3 MNV were included in this study. An age-, sex-, and stage-matched control group was composed of eyes affected by Type 3 MNV without sub-RPE multilaminar hyperreflectivity. Prevalence and treatment outcomes after anti-vascular endothelial growth factor injections at 1-year follow-up were analyzed in both groups.

RESULTS

Nineteen treatment-naïve eyes of 19 patients (8 men/11 women, mean age 83 ± 8 years old) presenting with sub-RPE multilaminar hyperreflectivity before or at the onset/clinical detection of Type 3 MNV were included from a cohort of 162 eyes with treatment-naïve Type 3 MNV. This accounts for an estimated prevalence of 11.7% (5.8-15.2, 95% confidence intervals). No significant differences were disclosed between cases studied and the control group (143 eyes of 143 patients) in age, sex, best-corrected visual acuity at baseline, and number of injections. Best-corrected visual acuity did not improve during the 1-year follow-up in patients showing sub-RPE multilaminar hyperreflectivity (P = 0.45), whereas best-corrected visual acuity significantly increased in the control group (P < 0.001). The presence of sub-RPE multilaminar hyperreflectivity in the context of Type 3 MNV was significantly associated with regressive calcific drusen (P < 0.001) and multiple Type 3 lesions/eye (P < 0.001).

CONCLUSION

The detection of multilaminar hyperreflectivity at the onset/clinical detection of Type 3 MNV suggests that chronic exudation (i.e., the "onion-sign") in the sub-RPE space (i.e., focal sub-RPE neovascularization) may precede the onset/clinical detection of Type 3 MNV. Sub-retinal pigment epithelium multilaminar hyperreflectivity at the onset of Type 3 MNV may be an important predictor of poor visual outcome in these eyes.

Ocular Imaging for Enhancing the Understanding, Assessment, and Management of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a progressive neuro-retinal disease and the leading cause of central vision loss among elderly individuals in the developed countries. Modern ocular imaging technologies constitute an essential component of the evaluation of these patients and have contributed extensively to our understanding of the disease. A challenge with any review of ocular imaging technologies is the rapid pace of progress and evolution of these instruments. Nonetheless, for proper and optimal use of these technologies, it is essential for the user to understand the technical principles underlying the imaging modality and their role in assessing the disease in various settings. Indeed, AMD, like many other retinal diseases, benefits from a multimodal imaging approach to optimally characterize the disease. In this chapter, we will review the various imaging technologies currently used in the assessment and management of AMD.

[Different types localisation of retinal fluid as prognostic biomarkers in the choice of anti-VEGF therapy for age-related macular degeneration]

Age-related macular degeneration is an advanced chronic disease and the main cause of vision loss in geriatric patients. Optical coherence tomography (OCT) is a modern method of retinal imaging allowing to detect different types of fluid: intraretinal fluid (IRF), subretinal fluid (SRF) and fluid under pigment epithelial detachment (PED). Finding relevant imaging biomarkers is necessary for identification of basic activity criteria of the disease, choosing treatment algorithms, determining treatment duration and termination criteria, and predicting the outcomes. Presence of IRF is associated with poor functional outcomes. Its presence is an indication for early beginning of treatment aimed at full resorption of the fluid with further possible careful extension of anti-VEGF therapy intervals with a regular follow-up. Degenerative intraretinal cysts developing in the background of subretinal fibrosis in absence of choroidal neovascularization (CNV) should be a sign for discontinuation of anti-VEGF therapy due to the lack of targets. Presence of SRF is associated with favorable outcomes and good treatment prognosis and is not a barrier to the extension of treatment intervals even up to the maximum of 16 weeks as described in existing randomized controlled trials, on the condition of no other CNV activity. PED with active CNV is one of the biomarkers that reveal the need for long-term aggressive therapy. In case of its size gain, it is necessary to restart the anti-VEGF treatment to prevent visual loss in the long-term. Combination of different fluid types is a sign of lasting disease history with a poor outcome prognosis. In this case, anti-VEGF treatment should be started as soon as possible with long-term fixed regimen or Treat-and-extend (T&E) with minimal suitable interval for the patient and precise monitoring of the condition of retina until complete suppression of activity. Developing a personalized approach in each case plays an important role in preserving visual functions.

Exudative non-neovascular age-related macular degeneration

PURPOSE

To describe the clinical and multimodal imaging (MMI) features of age-related macular degeneration (AMD) eyes presenting with intraretinal exudation and no evidence of neovascularization or structural alterations of native retinal vessels.

METHODS

This was a retrospective review of the MMI and electronic health records for 3 consecutive patients presenting with unilateral exudative non-neovascular age-related macular degeneration. MMI included confocal color fundus photography (CFP), fundus autofluorescence (FAF), fluorescein angiography (FA), spectral domain optical coherence tomography (SD-OCT), swept-source optical coherence tomography angiography (SS-OCTA), and spectral domain optical coherence tomography angiography (SD-OCTA). Dense B-scan OCTA (DB-OCTA) patterns and implemented image post-processing were used to improve spatial resolution in the OCTA analysis and remove projection artifacts.

RESULTS

Three eyes of 3 patients (1 male and 2 females, ages 72-87) developed intraretinal fluid (IRF) producing retinal edema during regular follow-up for non-neovascular AMD. FA, SS-OCTA, and DB-OCTA demonstrated no evidence of macular neovascularization or discrete retinal vascular abnormalities that could explain the IRF accumulation. Two eyes received intravitreal anti-VEGF therapy and demonstrated prompt resolution of IRF with periodic recurrences over time.

CONCLUSION

Exudative non-neovascular AMD is a novel clinical phenotype characterized by the presence of non-neovascular intraretinal exudation producing macular edema. Differentiating this condition from other manifestations of AMD requires appropriate use of MMI. Further study is needed to assess the clinical impact and optimal management of exudative non-neovascular AMD.

Multimodal Imaging to Detect in vivo Responses to Aflibercept Therapy in a Mouse Model of Type 3 Neovascularization

PURPOSE

The aim of this study was to characterize the response to aflibercept in a mouse model of type 3 neovascularization, the neoretinal vascularization (NRV) 2 mouse line.

METHODS

Twelve NRV2 mice were assigned to one of the following groups: (1) 6 mice were injected with aflibercept 3 µg/g at postnatal day (P) 15 ("aflibercept" group), and (2) the remaining 6 mice did not receive any treatment ("placebo" group). The mice were examined at P30 and P44.

RESULTS

The NRV mice's retinas were characterized by regions of depigmentation that were topographically associated with hyperfluorescent lesions seen on fluorescein angiography (FA) images. On optical coherence tomography images, intraretinal neovascularizations were visualized as hyperreflective lesions mainly localized within the outer plexiform and outer nuclear layers. The average number of intraretinal neovascular lesions visualized on FA at P30 was 5.0 ± 2.2 in the aflibercept group and 20.7 ± 2.4 in the placebo group (p < 0.0001). At P44, the average number of intraretinal lesions was still lower in the aflibercept group, although this difference was not statistically significant (p = 0.088).

CONCLUSION

Aflibercept therapy was effective in inhibiting pathologic angiogenesis in the NRV2 mouse model. However, the successive treatment washout resulted in an increase in the number of lesions.

SENSITIVITY OF 840-nm SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN DETECTING TYPE 1 NEOVASCULARIZATION ACCORDING TO THE HEIGHT OF THE ASSOCIATED PIGMENT EPITHELIAL DETACHMENT

PURPOSE

To evaluate the ability of optical coherence tomography angiography (OCTA) to detect abnormal vascular blood flow in Type 1 neovascularization (NV) with or without significant pigment epithelial detachment (PED).

METHODS

Consecutive age-related macular degeneration patients with either treatment-naive or anti-vascular endothelial growth factor-treated Type 1 NV were divided into 2 groups based on the PED height on structural OCT: greater than 250 μm (Group 1) versus less than 250 μm (Group 2). Two independent senior retina specialists analyzed the OCTA images (Zeiss Angioplex OCT, Carl Zeiss AG, Jena, Germany) using the automatic slabs alone (first reader) versus automatic and manual segmentation slabs (second reader).

RESULTS

In Group 1, 15 men and 42 women, aged from 51 years to 97 years (mean: 87.5), were included. Optical coherence tomography angiography was able to show an abnormal blood flow suggestive of Type 1 NV in 23 (40.3%) of 57 eyes for the first reader and in 32 (56.1%) of 57 eyes for the second reader. In Group 2, 7 men and 30 women, aged from 60 years to 96 years (mean: 80.2), were included. The first and second readers were able to observe an image suggestive of Type 1 NV in 33/37 (89.2%) and 37/37 (100%) of eyes, respectively.

CONCLUSION

The ability of OCTA to detect an abnormal blood flow in Type 1 NV was found to highly depend on the height of the associated PED and the use of manual segmentation slabs. Our results suggest that automatic slabs of OCTA should be interpreted with caution for the diagnosis of vascularized PED. The diagnosis of Type 1 NV using OCTA requires the use of manual segmentation and a multimodal imaging approach, especially when the height of the associated PED is >250 μm.

The long-term effects of anti-vascular endothelial growth factor therapy on the optical coherence tomography angiographic appearance of neovascularization in age-related macular degeneration

Background

The short-term effects of anti-vascular endothelial growth factor (anti-VEGF) treatment on macular neovascularization (MNV) morphology is well described, but long-term studies on morphologic changes and correlation of such changes to the type of MNV have not been conducted. This study aims to determine if different types of MNVs in neovascular AMD (nAMD) behave differently with anti-VEGF treatment as visualized on optical coherence tomography angiography (OCTA).

Methods

Treatment-naïve nAMD patients were retrospectively screened for baseline and follow-up OCTA imaging 10 or more months after initial treatment. Images were graded for MNV type, area, activity, mature versus immature vessels, vessel density, presence of atrophy, atrophy location and area. Growth rate was calculated as the percent change in lesion area from baseline over the years of follow-up. In addition, the occurrence of complete regression and the percent of lesions that grew, remained stable, and shrunk per type was also evaluated.

Results

Forty-three eyes from 43 patients with a mean follow-up of 2 years were evaluated. On structural OCT, 26 lesions were classified as pure type 1 MNVs, 12 MNVs had a type 2 component, and 5 MNVs had a type 3 component. Of these cases, 2 mixed-type MNVs were considered to have completely regressed. There was no significant differences in MNV area and growth rate between type 1 and type 2 lesions, but all cases of type 3 lesions shrunk in the follow-up period. There was no correlation between the number of injections per year and growth rate, endpoint MNV area or endpoint activity status for any MNV type. There was no significant association between the development of atrophy and the number of injections, baseline MNV area, baseline vessel density, or lesion growth rate.

Conclusions

In nAMD, complete regression of an MNV network exposed to anti-VEGF is rare. This work emphasizes the role of anti-VEGF as anti-leakage rather than vascular regression agents in nAMD.

Optical Coherence Tomography Findings (SD-OCT and OCTA) in Early-Stage Type 3 Neovascularization

A 76-year-old male presented with a small hyperreflective density in the outer nuclear layer with subtle retinal pigment epithelium (RPE) elevation and few intraretinal cysts on spectral-domain optical coherence tomography (SD-OCT). Optical coherence tomography angiography (OCTA) confirmed the presence of a tuft-shaped intraretinal neovascular lesion. SD-OCT performed 2 months before showed a smaller RPE elevation at the same location without intraretinal fluid. A 79-year-old male presented with a small hyperreflective density in the outer retina surrounded by scant intraretinal fluid on SD-OCT and a bright vessel on OCTA, suggesting early-stage type 3 neovascularization. SD-OCT performed 2 months before showed a smaller hyperreflectivity at the same location, without intraretinal fluid. An 84-year-old female presented with hyperreflective foci in the outer retina overlying a serous pigment epithelium detachment (PED) with focal RPE disruption on SD-OCT. SD-OCT performed 2 months before showed the same hyperreflective lesion associated with a shallower PED. No neovascular lesions were found on OCTA after six injections of bevacizumab. To conclude, careful evaluation of SD-OCT allows for early detection of type 3 neovascularization at a pre-exudative stage. OCTA may be useful in confirming the presence of intraretinal neovascular lesion and monitoring response to anti-vascular endothelial growth factor agents.