Vascular maturity of type 1 and type 2 choroidal neovascularization evaluated by optical coherence tomography angiography

Prognostic factors for intravitreal conbercept in the treatment of choroidal neovascularization secondary to pathological myopia

PURPOSE

To identify risk factors influencing visual outcomes in patients with pathological myopia-associated choroidal neovascularization (PM-CNV) following intravitreal injections of conbercept.

METHODS

A total of 86 eyes from 86 patients received intravitreal conbercept in a 1 + PRN regimen. After the initial injection, patients were followed for 12 months. They were categorized into two groups based on their 12-month visual acuity change: those who achieved greater than a one-line improvement in BCVA (improved group; n = 65) and those who experienced a one-line or lesser improvement or a decrease in BCVA (non-improved group; n = 21).

RESULTS

Over the 12-month period, the mean BCVA in the improved group significantly improved from 0.82 to 0.41 LogMAR. In the non-improved group, BCVA changed from 1.24 to 1.09 LogMAR. Similarly, the mean CRT decreased from 426.21 μm at baseline to 251.56 μm at 12 months in the improved group, and from 452.47 to 382.45 μm in the non-improved group. Multivariable logistic regression analyses revealed that older age (OR 1.287; 95% CI 1.019-1.625; P = 0.034), poorer baseline BCVA (OR 6.422; 95% CI 1.625-25.384; P = 0.008), the presence of subfoveal CNV (OR 4.817; 95% CI 1.242-18.681; P = 0.023), and organized interlacing patterns of CNV morphology (OR 5.593; 95% CI 1.397-22.392; P = 0.015) emerged as independent risk factors correlated with worsened visual prognosis following intravitreal conbercept injections.

CONCLUSIONS

Conbercept demonstrates significant efficacy and safety in treating PM-CNV. Key factors influencing visual recovery post-treatment include older age, poorer baseline BCVA, the presence of subfoveal CNV, and organized interlacing patterns of CNV morphology.

Quantitative Optical Coherence Tomography Detection of New Neovascular Branches and Association With Exudation Recurrence in Neovascular Age-Related Macular Degeneration

Purpose

The purpose of this study was to investigate the clinical role of multi-signal quantitative optical coherence tomography angiography (OCTA) perfusion sampling in neovascular age-related macular degeneration (AMD).

Methods

The study was designed as a cross-sectional case series. We collected data from already treated macular neovascularization (MNV), characterized by (I) clinically relevant recurrent exudation, (II) nonclinically relevant recurrent exudation, and (III) inactive lesion. We proposed a new OCTA metric, calculating the gap between high-resolution (HR) and high-speed (HS) OCTA samplings, hypothesizing that this gap might improve the detection of new secondary MNV branches, being also associated with exudation recurrence. Main outcome measures were the HR-HS gap-based categorization of MNV lesions and the assessment of its association with exudative, minimally exudative, and inactive lesions.

Results

Our cohort (which consisted of 32 MNV eyes; 32 patients; mean disease duration 5 years) was classified as type 1 (17; 53%), type 2 (11; 34%), or mixed type (4; 13%) MNV. Subretinal fibrosis was found in 17 out of 32 eyes (53%), whereas outer retinal atrophy involved 22 of 32 eyes (69%). HR-HS MNV gap was significantly different among MNV subgroups: 18% for the exudative subgroup, 12% for the minimally exudative subgroup, and 4% for the inactive subgroup. HR-HS gap significantly correlated with best corrected visual acuity (BCVA), disease duration, fibrosis, and outer retinal atrophy.

Conclusions

HR-HS gap is a novel quantitative metric to detect the secondary novel branches of AMD-related MNV. This parameter is clinically relevant because it is associated with fluid recurrence. The integration of HR-HS gap in artificial intelligence models might help to predict MNV reactivation and to optimize treatment strategies.

Pachychoroid neovasculopathy versus macular neovascularization in age-related macular degeneration with and without shallow irregular pigment epithelial detachment

To compare the choroidal neovascular features of individuals with pachychoroid neovasculopathy (PNV) and neovascular age-related macular degeneration (nAMD) with and without shallow irregular pigment epithelial detachment (SIPED). Using optical coherence tomography angiography, the choroidal neovascular complexes of 27 patients with PNV, 34 patients with nAMD and SIPED, and 15 patients with nAMD without SIPED were analyzed with FIJI and AngioTool software. PNV compared to nAMD with SIPED had a greater vessel percentage area (P = 0.034), junction density (P = 0.045), average vessel length (P < 0.001), and fractal dimension (P < 0.001). PNV, compared to nAMD without SIPED, had a greater total vessel length (P = 0.002), total number of junctions (P < 0.001), junction density (P = 0.034), and fractal dimension (P = 0.005). nAMD with SIPED, compared to nAMD without SIPED, had greater vessel area, total number of junctions, total vessel length, and average vessel length (all P values < 0.001). Patients with nAMD plus SIPED and individuals with nAMD without SIPED have similar fractal dimension values (P = 0.703). Biomarkers of choroidal neovascular complexity, such as fractal dimension, can be used to differentiate PNV from nAMD with or without SIPED.

LONG-TERM MORPHOLOGIC CHANGES IN MACULAR NEOVASCULARIZATION UNDER AFLIBERCEPT TREATMENT WITH A TREAT-AND-EXTEND REGIMEN

PURPOSE

To examine the morphologic changes in macular neovascularization (MNV) secondary to age-related macular degeneration after 2 years of aflibercept treatment under a treat-and-extend (T&E) regimen.

METHODS

This retrospective study analyzed the medical records for 26 eyes of 25 patients diagnosed with treatment-naive neovascular age-related macular degeneration and treated with aflibercept under a treat-and-extend regimen for 2 years. The areas of the MNV and vascular structures were assessed using swept-source optical coherence tomography angiography at baseline and after 2 years of treatment.

RESULTS

The mean MNV area increased significantly from 0.65 ± 0.42 mm 2 at baseline to 0.78 ± 0.45 mm 2 at 2 years. At 2 years, the mean change in the MNV area from baseline was 22% (interquartile range: 4%-60%). The baseline MNV area was negatively correlated with the change ratio of the MNV areas at 2 years and baseline ( R = -0.68, P < 0.001). Nine of the 26 eyes (34.6%) showed newly formed mature vessels, and 7 eyes (26.9%) showed prominently developing preexisting mature vessels.

CONCLUSION

Macular neovascularization expanded and showed vascular maturation under aflibercept treatment with a treat-and-extend regimen. The smaller the MNV at baseline, the greater is its expansion in 2 years.

The Architecture of Macular Neovascularizations Predicts Treatment Responses to Anti-VEGF Therapy in Neovascular AMD

Introduction: Anti-VEGF therapy is an effective option for improving and stabilizing the vision in neovascular age-related macular degeneration (nAMD). However, the response to treatment is markedly heterogeneous. The aim of this study was therefore to analyze the vascular characteristics of type 1,2, and 3 macular neovascularizations (MNV) in order to identify biomarkers that predict treatment response, especially with regard to changes in intraretinal and subretinal fluid. Materials and Methods: Overall, 90 treatment-naive eyes with nAMD confirmed by optic coherence tomography (OCT), fluorescein angiography, and OCT angiography (OCTA) were included in this retrospective study. The MNV detected by OCTA were subjected to quantitative vascular analysis by binarization and skeletonization of the vessel using ImageJ. We determined their area, total vascular length (sumL), fractal dimension (FD), flow density, number of vascular nodes (numN), and average vascular diameter (avgW). The results were correlated with the treatment response to the initial three injections of anti-VEGF and the changes in intraretinal (IRF) and subretinal fluid (SRF) and the occurrence of pigment epithelial detachements (PED). Results: All patients found to have no subretinal or intraretinal fluid following the initial three injections of anti-VEGF showed a significantly smaller MNV area (p < 0.001), a lower sumL (p < 0.0005), and lesser FD (p < 0.005) before treatment than those who still exhibited signs of activity. These parameters also showed a significant influence in the separate analysis of persistent SRF (p < 0.005) and a persistent PED (p < 0.05), whereas we could not detect any influence on changes in IRF. The vascular parameters avgW, numN, and flow density showed no significant influence on SRF/IRF or PED changes. Conclusions: The size, the total vessel length, and the fractal dimension of MNV at baseline are predictors for the treatment response to anti-VEGF therapy. Therefore, particularly regarding the development of new classes of drugs, these parameters could yield new insights into treatment response.

Characterisation of macular neovascularisation subtypes in age-related macular degeneration to optimise treatment outcomes

The aim of this review is to identify the common characteristics and prognoses of different subtypes of neovascular age-related macular degeneration (nAMD). We also propose recommendations on how to tailor treatments to the subtype of neovessels to optimise patient outcomes. The authors, selected members of the Vision Academy, met to discuss treatment outcomes in nAMD according to macular neovascularisation (MNV) subtypes, using evidence from a literature search conducted on the PubMed database (cut-off date: March 2019). This review article summarises the recommendations of the Vision Academy on how the characterisation of MNV subtypes can optimise treatment outcomes in nAMD. The identification of MNV subtypes has been facilitated by the advent of multimodal imaging. Findings from fluorescein angiography, indocyanine green angiography and spectral-domain optical coherence tomography collectively help refine and standardise the determination of the MNV subtype. To date, three subtypes have been described in the literature and have specific characteristics, as identified by imaging. Type 1 MNV is associated with better long-term outcomes but usually requires more intense anti-vascular endothelial growth factor dosing. Type 2 MNV typically responds quickly to treatment but is more prone to the development of fibrotic scars, which may be associated with poorer outcomes. Type 3 MNV tends to be highly sensitive to anti-vascular endothelial growth factor treatment but may be associated with a higher incidence of outer retinal atrophy, compared with other subtypes. Accurately assessing the MNV subtype provides information on prognosis and helps to optimise the management of patients with nAMD.

The Influence of COVID-19 on the Stability of Patients with Neovascular Age-Related Macular Degeneration with Different Treatment Regimens

Introduction

To explore the impact of coronavirus disease 2019 (COVID-19) on the stability of patients with neovascular age-related macular degeneration (nAMD) receiving the treat and extend (T&E) or the pro re nata (PRN) treatment regimen and to identify indicators that may predict the disease stability of nAMD.

Methods

This is a retrospective study of patients with nAMD treated at the Second Affiliated Hospital of Harbin Medical University whose treatment schedule was interrupted at least once between 1 February and 31 May 2020. The demographic and clinical characteristics, including the best corrected visual acuity (BCVA), optical coherence tomography (OCT) features, subfoveal choroidal thickness (SFCT), interval between the last injection and the beginning of the pandemic, and the number of anti-vascular endothelial growth factor (VEGF) injections, were analyzed.

Results

A total of 209 stable patients with nAMD (122 eyes received the T&E regimen; 87 eyes received the PRN regimen) were identified. Compared to those who received the PRN regimen, the patients who received the T&E regimen were more stable during the first visit after COVID-19 (53.3% vs. 33.3%, P = 0.004), the BCVA was significantly better (58.5 letters vs. 56 letters, P = 0.006), and the CRT fluctuated only slightly (15 μm vs. 35 μm, P = 0.001). Furthermore, a multivariate logistic regression analysis showed that stable patients with nAMD with type 1 choroidal neovascularization (CNV) (OR 2.493 [95% CI 1.179–5.272], compared with type 2 CNV; P = 0.017; OR 2.912 [95% CI 1.133–7.485], compared with retinal angiomatous proliferation; P = 0.026) or with pigment epithelial detachment (PED) were more likely to remain stable when treatment was interrupted (OR 0.392 [95% CI 0.181–0.852], compared with no PED; P = 0.018).

Conclusion

Compared to patients who received the PRN treatment regimen, stable patients with nAMD who received the T&E treatment regimen could better maintain stability when the treatments were suddenly interrupted by the COVID-19 pandemic. In addition, patients with type 1 CNV or patients with PED were more likely to remain stable. At present, the COVID-19 pandemic is becoming increasingly normalized, and the T&E regimen can become a more advanced treatment option for patients undergoing therapy.

Vascular Analysis of Type 1, 2, and 3 Macular Neovascularization in Age-Related Macular Degeneration Using Swept-Source Optical Coherence Tomography Angiography Shows New Insights into Differences of Pathologic Vasculature and May Lead to a More Personalized Understanding

Background: The clinical appearance of macular neovascularization (MNV) in age-related macular degeneration (nAMD) varies widely, but so far, this has had no relevance in terms of therapeutic approaches or prognosis. Therefore, our purpose was to investigate if and which differences exist in the vascular architecture of MNV and to quantify them. Methods: In 90 patients with newly diagnosed nAMD, MNV was identified by means of optical coherence tomography angiography (OCTA), and automated quantitative vascular analysis was carried out. The analyzed vascular parameters were area, flow, fractal dimension (FD), total vascular length (sumL), number of vascular nodes (numN), flow, and average vessel caliber (avgW). The current classification of MNVs divides them according to their localization into type 1 (grown from the choroid below the RPE), type 2 (grown from the choroid through RPE), and type 3 (grown from the retina toward the RPE). We compared the analyzed vascular parameters of each of the three MNV types. Kruskal−Wallis test was applied, Dunn test was performed for post hoc analysis, and for pairwise comparison, p-values were adjusted using Bonferroni comparison. Results: Regarding the MNV area, there was no significant difference between types 1 and 2, but type 3 was significantly smaller than types 1 and 2 (p < 0.00001). For FD, types 1 and 2 did not differ significantly, but again, type 3 was lower than type 1 and 2 (p < 0.00001). The numN were significantly higher in types 1 and 3 than in 2 (p < 0.005), but not between types 1 and 3. No significant differences were found between MNV types for flow. As for sumL, types 1 and 2 did not differ significantly, but type 3 was significantly lower than types 1 and 2 (p < 0.00001). For avgW, there was no significant difference between types 1 and 2 or between types 2 and 3, but type 3 was significantly larger than type 1 (p < 0.05). Conclusions OCTA yields detailed information on the vascular morphology of MNV in patients with nAMD and is able to show differences among types 1, 2, and 3. Especially comparing types 1 and 2 with type 3 reveals significant differences in area, FD, sumL, and numN. One explanation could be the similar pathogenesis of types 1 and 2 with their origin in the choroid and their growth towards the retinal pigment epithelium (RPE), whereas type 3 originates in the deep capillary plexus. Between types 1 and 2, however, only the numN differ significantly, which could be due to the fact that type 1 spreads horizontally below the RPE and, thus, display more vascular branching, while type 2 grows more vertically through the RPE and under the neurosensory retina. Detailed information about the pathologic vasculature is important for proper monitoring of the disease and to assess the efficacy of medication, especially with regard to new substances. This should be taken into consideration in future studies.

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.

Correlation of retinal alterations with vascular structure of macular neovascularisation in swept-source optical coherence tomography angiography in age-related macular degeneration

Purpose

The aim of this study was to find out whether the vascular architecture of untreated macular neovascularisations (MNV) in neovascular age-related macular degeneration (nAMD) as visualised with optic coherence tomography angiography (OCTA) is associated with functional and known morphological alterations of the retina in optic coherence tomography (SD-OCT).

Methods

The study design was retrospective with consecutive patient inclusion. In 107 patients with newly diagnosed nAMD, MNV were detected by means of OCTA and automated quantitative vascular analysis was performed. The MNV characteristics measured were area, flow density, total vascular length (sumL), density of vascular nodes (numN), fractal dimension (FD) and average vascular width (avgW). These parameters were assessed for associations with vision (BCVA), central retinal thickness (CRT), fluid distribution, the elevation of any pigment epithelial detachment (PED), the occurrence of subretinal haemorrhage and atrophy.

Results

BCVA was significantly worse with greater MNV area and sumL. Fluid distribution differed significantly in relation to area (p < 0.005), sumL (p < 0.005) and FD (p = 0.001). Greater PED height was significantly associated with higher numN (p < 0.05) and lower avgW (p < 0.05). Atrophy was present significantly more often in MNV with larger area (p < 0.05), higher sumL (p < 0.05) and higher flow density (p = 0.002). None of the MNV parameters had a significant association with CRT or the occurrence of haemorrhage.

Conclusion

OCTA is not restricted to evaluation of secondary changes but offers the opportunity to analyse the vascular structure of MNV in detail. Differences in vascular morphology are associated with certain secondary changes in retinal morphology. There are thus grounds for optimism that further research may identify and classify OCTA-based markers to permit more individualised treatment of nAMD.

MORPHOLOGICAL AND ANATOMICAL FEATURES OF TYPE 1 MACULAR NEOVASCULARIZATION TRUNKS IN AGE-RELATED MACULAR DEGENERATION USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To evaluate the morphological features of macular neovascularization (MNV) trunks at different layers using optical coherence tomography angiography (OCTA).

METHODS

Type 1 MNV trunks in age-related macular degeneration were retrospectively evaluated at the sub-retinal pigment epithelium (subRPE) and sub-Bruch's membrane (subBM) layers. The detectability and location of the trunks were compared. MNV trunks at the subBM layer on OCTA b-scans were evaluated using a flow overlay. The correlations of the MNV trunk with OCTA and OCT parameters were evaluated.

RESULTS

Among the 63 included eyes, 27 showed core vessels at the subRPE layer and 52 showed MNV trunks at the subBM layer, which were connected with the MNV at the subRPE layer. The locations of the MNV trunks in each layer were different. MNV trunk types at the subBM layer were related to disease duration, distance from the large choroidal vessels, and MNV vessel density. The large choroidal vessel diameter was correlated with the MNV trunk diameter at the subBM layer.

CONCLUSION

MNV trunks at the subBM layer were detected more frequently than distal MNV trunks at the subRPE layer. MNV trunk features at the subBM layer may be related to disease duration and a large choroidal vessel.

Nonexudative morphologic changes of neovascularization on optical coherence tomography angiography as predictive factors for exudative recurrence in age-related macular degeneration

PURPOSE

To evaluate morphologic changes of choroidal neovascularization (CNV) on optical coherence tomography angiography (OCTA) during the nonexudative period and to correlate the features and timing of recurrence in neovascular age-related macular degeneration. (AMD).

METHODS

Two hundred thirty-eight eyes with type 1 CNV were retrospectively reviewed. For cases with exudative recurrence, OCTA images were tracked for analysis between the recurrences. Qualitative parameters of morphologic changes of CNV on OCTA, including tiny branching vessels, anastomotic loops, peripheral vascular arcade, and perilesional halo, were correlated with the features of exudative recurrence.

RESULTS

Exudative recurrence was identified in 163 cases, and among them, nonexudative morphological changes in CNV were identified using OCTA in 45 cases. For the cases with nonexudative changes on OCTA, exudative recurrence eventually developed within 0.5-3.5 months (mean, 2.3 ± 2.0 months) after identifying morphologic changes OCTA. The following changes in CNV were revealed on OCTA: tiny branching vessels in 53.3% (24/45) of cases, anastomotic loops in 40.0% (18/45), peripheral vascular arcades in 44.4% (20/45), and perilesional halo in 35.6% (16/45). Among the morphologic parameters, development of tiny branching vessels was significantly associated with early exudative recurrence (1.5 ± 1.2 months, p = 0.019), higher incidence of intraretinal fluid (IRF) (p = 0.016), and subretinal or subretinal pigment epithelial hemorrhage (p = 0.023) at recurrence, compared with other morphologic changes.

CONCLUSION

Development of tiny branching vessels of CNV on OCTA during the nonexudative period was associated with early exudative recurrence, including IRF or hemorrhage. Identifying the nonexudative changes of CNV on OCTA might predict exudative recurrence and provide additional parameters for monitoring neovascular AMD.

Analyses of the effects of persistent subretinal fluid on visual/anatomic outcomes according to the type of macular neovascularization during the relaxed treat-and-extend protocol in age-related macular degeneration patients

Background

To analyze the long-term effects of persistent subretinal fluid (SRF) on visual/anatomic outcomes according to the type of macular neovascularization (MNV) during relaxed treat-and-extend regimen with anti-vascular endothelial growth factor (anti-VEGF) agents in age-related macular degeneration (AMD) patients.

Methods

Patients with fovea-involving type 1 or type 2 MNV, treated with a relaxed treat-and-extend regimen for 2 years were retrospectively reviewed. Eyes with SRF observed more than three times per year were defined as the ‘persistent SRF (+) group’. To exclude the effects of IRF as much as possible, the eyes with persistent IRF were excluded. The effects of persistent SRF on the best-corrected visual acuity (BCVA), central subfield retinal thickness (CST), and changes in the photoreceptor layer (PRL) thickness and outer retinal bands (external limiting membrane, ellipsoid zone, and cone outer segment tip line) after anti-VEGF injection were analyzed for each MNV type.

Results

Seventy-seven eyes with type 1 MNV (44 eyes with persistent SRF) and 53 eyes with type 2 MNV (18 eyes with persistent SRF) were enrolled. Following a relaxed treat-and-extend regimen with anti-VEGF agents, BCVA and CST improved for each MNV type. In comparison between persistent SRF (+) and persistent SRF (−) group, there were no differences in the amount of change in BCVA and CST between the two groups for each MNV type during 2-year follow-up periods. In addition, there were no differences in the amount of reduction in PRL thickness and state of the outer retinal bands between the two groups for each MNV type.

Conclusions

Using a relaxed treat-and-extend regimen with anti-VEGF agents, persistent SRF did not have additional effects on visual and anatomic outcomes by 2 years, regardless of the MNV type.

[Influence of CNV vascular morphology in exudative age-related macular degeneration on development of visual acuity and need for anti-VEGF therapy after 1 year]

BACKGROUND

The aim of this pilot study was to investigate vascular morphological characteristics of choroidal neovascularization (CNV) at the time of the initial diagnosis of exudative age-related macular degeneration (nAMD), which enable a prognosis for the development of visual acuity and the necessity for treatment in the first year.

METHODS

In 57 patients with the initial diagnosis of nAMD, CNV was detected by optical coherence tomography angiography (OCT-A) and an automated quantitative vessel analysis was performed with respect to area, total vessel length, flow value and average vessel caliber of the CNV. After 12 months patients were divided into 2 groups based on visual acuity (visual loss vs. visual gain) and necessity of anti-VEGF therapy (<7 intravitreal injections, IVOM vs. ≥7 IVOM).

RESULTS

The mean CNV area was 0.95 mm² ± 1.07 mm² (group visual loss 1.56 mm² ± 1.54 mm²; group visual gain 0.65 mm² ± 0.53 mm²; p = 0.002/<7 IVOM 1.05 mm² ± 1.40 mm²; ≥7 IVOM 0.98 mm² ± 0.94 mm², p = 0.60). The average total vessel length of the CNV was 9.84 mm ± 11.35 mm (visual loss 16.00 mm ± 16.58 mm; visual gain 6.74 mm ± 5.42 mm; p < 0.003/<7 IVOM 11.21 mm ± 15.10; ≥7 IVOM 9.90 mm ± 9.68 mm; p = 0.68). The mean flow value of the CNV was 0.40 ± 0.06 (visual loss 0.37 ± 0.04; visual gain 0.41 ± 0.07; p = 0.004/<7 IVOM 0.42 ± 0.08; ≥7 IVOM 0.38 ± 0.06; p = 0.02). The average vessel caliber was 28.86 µm ± 2.93 µm (visual loss 28.39 µm ± 2.97 mm; visual gain 29.32 µm ± 3.05 µm; p = 0.24/<7 IVOM 30.26 µm ± 3.49 µm; ≥7 IVOM 28.23 µm ± 2.25 µm; p = 0.02).

CONCLUSION

The results show that a mathematical quantification of the CNV in nAMD is possible using OCT‑A. This analysis confirmed again that the size of the CNV (area and total vessel length) is decisive for the prognosis of visual acuity. It also shows that a larger flow value as a sign of a well-differentiated CNV is associated with a better functional prognosis. The number of IVOMs required, however, depends primarily on the composition of the CNV (flow value and vascular caliber). More precise imaging and larger examination cohorts could possibly reveal further relevant biomarkers.

Diagnostic Value of Optical Coherence Tomography Angiography for Choroidal Neovascularization in Age-Related Macular Degeneration: A Systematic Review and Meta-Analysis

OBJECTIVE

This study aims to evaluate the diagnostic value of optical coherence tomography angiography (OCTA) in detecting the choroidal neovascularization (CNV) in age-related macular degeneration (AMD).

METHODS

A systematic review and meta-analysis was performed by searching Pubmed, Science Direct, Embase, and Web of Science. The pooled sensitivity and specificity with 95% confidence intervals (CIs), area under the summary receiver operator characteristic curve (sROC), and the total accurate classification rate were used to evaluate OCTA's diagnostic value of CNV in AMD patients.

RESULTS

Seven studies involving 517 eyes were included in the analysis. The mean age of subjects in each study ranged from 58.5 years to 81.7 years. Fluorescein angiography was applied as the gold standard in 5 studies. There were 350 eyes diagnosed with CNV, OCTA detected 301 eyes correctly, while among the 167 eyes without CNV, OCTA identified 150 correctly. The total accurate classification rate was 87.23%. The Spearman's rank correlation coefficient was 0.5, indicating that there was no significant threshold effect in the current study (S = 8, p = 0.103). The pooled sensitivity and pooled specificity were 0.89 (95% CI: 0.82, 0.94) and 0.96 (95% CI: 0.85, 1.00), respectively. The area under sROC was up to 0.911.

CONCLUSION

The specificity of OCTA for the detection of CNV in AMD patients is extremely high; however, the sensitivity still needs to be improved. In general, the meta-analysis revealed that OCTA had a high diagnostic value for the detection of CNV in AMD patients.

Four-year outcome of aflibercept administration using a treat-and-extend regimen in eyes with recurrent neovascular age-related macular degeneration

PURPOSE

To investigate the 4-year outcome of aflibercept treatment using a treat-and-extend (TAE) regimen for recurrent neovascular age-related macular degeneration (AMD).

STUDY DESIGN

Retrospective observational study.

METHODS

Data of eyes with recurrent AMD previously treated with anti-vascular endothelial growth factor agents or photodynamic therapy and had started aflibercept treatment using a TAE regimen for the first time were collected. Best-corrected visual acuity (BCVA), intervals of treatments, the presence of exudation, central foveal thickness (CFT), and central choroidal thickness (CCT) were analyzed.

RESULTS

Of 47 consecutive eyes, 30 of the 47 eyes completed a 4-year follow-up. The mean BCVA (logMAR) was sustained over the 4 years (0.37 at baseline, 0.36 at 1 year, 0.36 at 2 years, 0.41 at 3 years, and 0.43 at 4 years, P = 0.21). Of the 30 eyes that completed the follow-up, BCVA of two eyes deteriorated by 0.3 logMAR or more at 4 years. At 4 years, 67% of eyes had extended treatment intervals to > 8 weeks, and 47% of eyes had extended intervals to > 12 weeks. Exudative changes in the macula, seen in all eyes at baseline, were only seen in 50% of the eyes at 4 years. The mean CFT and CCT decreased significantly at 4 years from 332 μm to 248 μm and from 218 μm to 183 μm, respectively.

CONCLUSION

In clinical settings, aflibercept treatment using a TAE regimen may successfully maintain visual acuity for up to 4 years even in recurrent cases of AMD.

Quantitative Comparison of the Vascular Structure of Macular Neovascularizations Between Swept-Source and Spectral-Domain Optical Coherence Tomography Angiography

Purpose

The aim of this study was to ascertain and quantify the differences between swept-source (SS) and spectral-domain (SD) optical coherence tomography angiography (OCTA) imaging of macular neovascularizations (MNV) in neovascular age-related macular degeneration (nAMD).

Patients and Methods

SD-OCTA (RTVue Avanti) and SS-OCTA (PLEX^® Elite 9000) were performed in 37 patients with MNV in nAMD. The MNV was delineated and the data were processed via ImageJ. The parameters MNV area, nodes per area, fractal dimension (FD), and flow density were analyzed using MatLab.

Results

There was close agreement between the two devices regarding MNV area (ICCc 0.977, ICCa 0.977, R² 0.977), but only slight agreement regarding nodes per area (ICCa 0.008, ICCc 0.548, R² 0.51), FD (ICCa 0.425, ICCc 0.846, R² 0.96), and flow density (ICCa 0.451, ICCc 0.656, R² 0.65). The difference between the two devices was insignificant for MNV area (type 1: p=0.328; type 2: p=0.426; type 3: p=0.615), but significant for nodes per area (type 1: p=0.002; type 2: p=0.00001; type 3: p=0.003), FD (type 1: p<0.00001; type 2: p<0.00001; type 3: p=0.015) and flow density (type 1: p=0.0004; type 2: p=0.004; type 3: p=0.052).

Conclusion

MNV area is closely comparable between devices using SS-OCTA and SD-OCTA imaging. However, the two methods differ significantly in their precise assessment of the vascular morphology (FD, flow density, nodes per area). Therefore, results obtained using different devices are not comparable and should not be amalgamated in clinical trials.

Impact of Sub-Retinal Fluid on the Long-Term Incidence of Macular Atrophy in Neovascular Age-related Macular Degeneration under Treat & Extend Anti-Vascular Endothelial Growth Factor Inhibitors

Sub-retinal fluid (SRF) has been discussed as a protective factor against macular atrophy in eyes with neovascular age-related macular degeneration (nAMD).To gauge the impact of SRF on macular atrophy, a database of 310 nAMD eyes was screened for eyes manifesting an SRF-only phenotype under treat & extend anti-VEGF treatment, defined as nAMD expressing CNV exudation beyond the three monthly anti-VEGF loading doses by SRF only without any signs of exudative intra-retinal fluid (IRF) for ≥3 years. Incidence of macular atrophy and treatment responses were evaluated on multimodal imaging, including optical coherence tomography (OCT), blue autofluorescence (BAF) and near-infrared (NIR) confocal scanning laser ophthalmoscopy and fluorescence and indocyanine green angiography (FAG/ICGA). In total, 27 eyes (8.7%) of 26 patients with a mean follow-up of 4.2 ± 0.9 (3–5) years met the inclusion criteria. Mean age was 72 ± 6 (range: 61–86) years. The SRF only phenotype was seen from baseline in 14 eyes (52%), and in 13 eyes (48%) after a mean 1.0 ± 1.3 (1–3) injections. In years 1 to 5, mean 7.5, 5.9, 6.1, 6.1 and 7.0 anti-VEGF injections were given (p = 0.33). Cumulative macular atrophy incidence was 11.5% at year 1, 15.4% throughout years 2 to 4, and 22.4% at year 5. In conclusion, eyes manifesting activity by SRF only in treat & extend anti-VEGF regimen for nAMD seem to exhibit rather low rates of macular atrophy during long-term follow-up. SRF might be an indicator of a more benign form of nAMD.

OCT Angiography Features of Neovascularization as Predictive Factors for Frequent Recurrence in Age-Related Macular Degeneration

PURPOSE

To investigate the features of neovascularization (NV) in eyes with neovascular age-related macular degeneration using optical coherence tomography angiography (OCTA) according to the treatment interval of intravitreal aflibercept injection (IVI).

DESIGN

Retrospective, interventional, comparative case series.

METHODS

Patients with type 1 NV treated with the "pro re nata" regimen after 3 loading IVI were classified into 2 groups based on the numbers of treatments during 12 months, specifically a stable group who required fewer than 2 injections and an unstable group who required more than 3 injections. Quantitative features of OCTA including NV area, NV length, NV density, endpoint density (open-ended vessels per unit length), junction density (vessel junction per unit length), lacunarity, and largest vessel caliber were compared between the 2 groups.

RESULTS

Among 71 eyes, 38 and 33 eyes were classified into the stable and unstable groups, respectively. The unstable group had higher endpoint densities (stable vs unstable: 2.72 vs 3.18; P = .03) and higher levels of lacunarity (0.177 vs 0.211; P = .028). The area, density, length of NV, junction density, and largest vessel caliber were not different between the 2 groups (P = .057, P = .184, P = .062, P = .160, and P = .473, respectively). Endpoint density was correlated with the unstable group in both univariate and multivariate analyses (P = .004, P = .002, respectively). A predictive model with an endpoint index demonstrated a sensitivity of 93.75% and a negative predictive value of 89.47% for the unstable group.

CONCLUSIONS

The characteristics of NV in eyes of exudative age-related macular degeneration with type 1 NV were different according to treatment requirements. Identifying the features of NV on OCTA might be helpful for predicting clinical outcomes and optimal treatment intervals.

Bruch's membrane pathology: A mechanistic perspective

Bruch's membrane, an extracellular matrix located between the retinal pigment epithelium and the choroid, plays a vital role as structural and functional support to the retinal pigment epithelium. Dysfunction of Bruch's membrane in both age-related macular degeneration and other ocular diseases is caused mostly by extracellular matrix degeneration, deposit formation, and angiogenesis. Although these factors are dealt in greater detail with respect to the cells that are degenerated such as the retinal pigment epithelium and the endothelial cells, the pathology involving the Bruch's membrane is often underrated. Since in most of the macular degenerations early degenerative changes are also observed in the Bruch's membrane, addressing only the cellular component without the underlying membrane will not yield an ideal clinical benefit. This review aims to discuss the factors and the mechanisms affecting the integrity of the Bruch's membrane, which would aid in developing an effective therapy for these pathologies.