Optical Coherence Tomography Angiography Signs of Vascular Abnormalization With Antiangiogenic Therapy for Choroidal Neovascularization

Choroidal thickness after anti-vascular endothelial growth factor in typical neovascular age-related macular degeneration - A systematic review and meta-analysis

Age-related macular degeneration (AMD) is one of the leading causes of blindness in the world and anti-vascular endothelial growth factor (VEGF) injections have been the standard of care for the wet/neovascular variant since 2004. Currently, there are conflicting reports regarding its effect on the choroid, which supplies outer retina with oxygen and other nutrients. We synthesize available information of anti-VEGF on choroidal thickness (CT) in treatment-naïve typical neovascular AMD patients during the initial 12-week loading phase. We found 43 studies involving 1901 eyes from 1878 patients were included. Meta-analysis of 35 studies reporting CT at baseline and after 12 weeks suggested a significant decrease in CT with anti-VEGF treatment. A greater mean change with aflibercept compared to ranibizumab was found in subgroup analyses of sub-foveal CT in types 1 and 2 macular neovascularization. The long-term consequences of reduced CT in neovascular AMD remain unclear and require further targeted studies.

Morphometrics of polypoidal choroidal vasculopathy lesions and choroidal vascular associated with treatment response using swept-source optical coherence tomography angiography

PURPOSE

To evaluate quantitative metrics of neovascularization lesions and choroidal vascular using swept-source optical coherence tomography angiography (SS-OCTA) in polypoidal choroidal vasculopathy (PCV) eyes, and investigate the relationship between imaging biomarkers and treatment outcomes of intravitreal anti-vascular endothelial growth factor (VEGF).

METHODS

We retrospectively recruited 56 PCV patients. Choroidal features included subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI). Quantitative metrics of neovascularization lesions included total vessel length (TVL), average vessel length (AVL), junction density (JD), total number of endpoints (TNE), and mean lacunarity (ML). We performed multivariate logistic and linear regression models to determine the prognostic factors for functional and morphological outcomes.

RESULTS

By comparison, functional good-responders had poorer best corrected visual acuity, higher TNE, and lower ML at baseline. Morphological good-responders had higher central retinal thickness, higher TNE, lower TVL and AVL, lower ML, lower SFCT and CVI. High-shrinkage of vessel area subgroup had higher JD and TNE, lower TVL and AVL, lower ML, lower SFCT and CVI. Multivariate analysis showed good morphological response was correlated with lower SFCT (P < 0.01). High-shrinkage subgroup was correlated with lower AVL (P = 0.017) and higher TNE (P < 0.01).

CONCLUSION

Quantitative metrics of neovascularization lesions and choroidal characteristics using SS-OCTA had the potential to be imaging biomarkers for predicting the response to anti-VEGF treatment. PCV lesions with higher TNE and lower AVL tended to appear higher shrinkage of vessel area, and lower SFCT was correlated with good morphological response.

Fibrosis in age-related neovascular macular degeneration in the anti-VEGF era

The natural history of neovascular age-related macular degeneration (nAMD) leads to scarring and loss of vision. Since the advent of anti-VEGF therapies, which are very effective for controlling exudation, large disciform scars are rarely encountered in the clinic. However long term studies show that smaller and less severe fibrotic scars are not uncommon and develop over time despite optimal treatment. This means that additional mechanisms of action may be required to completely address this condition. To permit new treatments, a proper understanding of the clinical impact of fibrosis is required. This review is focused on clinical aspects of fibrosis and summarises recent data on biomarkers, prevalence, causes, consequences, and therapies, highlighting the most important and urgent topics to tackle in order to advance in the treatment of fibrosis.

Multimodal imaging features of retinal neovascularization in response to 3 anti-VEGF injections

OBJECTIVE

To analyze longitudinal changes of retinal neovessels (NV) in eyes with proliferative diabetic retinopathy (PDR) after 3 monthly intravitreal injections (IVI) of ranibizumab by means of different imaging modalities, particularly focusing on optical coherence tomography (OCT) and OCT-angiography (OCT-A) features.

METHODS

Prospective, monocentric study, Luigi Sacco Hospital, Milan. Consecutive patients with PDR were enrolled. All patients underwent color fundus photography (CFP), fluorescein angiography (FA), SD-OCT, and OCT-A at baseline (t0) and after 3 monthly IVI of ranibizumab (t1). Neovessels (NVs) were classified as flat, elevated, flat-elevated, or table-top using OCT scans and further analyzed on FIJI. Qualitative and quantitative NV characteristics were evaluated. Vessel density (VD) was calculated as the mean of all the white pixels of the NV and expressed as a percentage of the area of the NV (VD = NV area × 100).

RESULTS

Thirty-six NVs in 10 patients were studied. The regression of NVs at t1 was partial in 66.7% of cases and complete in 33.3%. Table-top NV demonstrated more frequently a complete regression (P = .03). A significant reduction of the NV area, perimeter, and VD was observed at t1 (P < .001). NVs that showed a complete regression had higher mean VD values at t0 compared with NVs, which showed a partial regression (P = .02). Flat NVs had more frequently a complete vitreous attachment, while table-top showed more often a partial vitreous detachment with focal NV adhesion (P < .05). A complete regression was more often observed for NVs with a partial vitreous detachment and focal NV adhesion at t0 (10/12), while most of the NVs with a complete vitreous attachment showed a partial regression (18/24) (P < .001).

CONCLUSIONS

The table-top configuration of the neovessel, higher VD values at baseline, and the presence of a focal adhesion of the vitreous over the NV were factors associated with a higher risk of complete regression of the NV in response to 3 monthly IVI of ranibizumab.

Regression of the Flow Signal from the Neovascular Network in AMD Neovascular Membranes Treated with Faricimab

OBJECTIVES

To report the occurrence of the regression of the flow signal from the neovascular network in macular neovascularizations (MNVs), developing in the context of age-related macular degeneration (AMD), treated with faricimab in a treat-and-extend regimen.

METHODS

Eyes affected by AMD-related MNV and treated with faricimab intravitreal injections in a treat-and-extend (TE) regimen were consecutively retrospectively screened in five specialized retina centers. Changes in neovascular network characteristics during the course of the treatment were analyzed. The availability of high-quality optical coherence tomography angiography (OCTA) at the beginning of the treatment and at the regression of the MNV was necessary for inclusion. According to greatest linear diameter (GLD) changes during treatment, eyes were divided into three groups: a complete regression (CR) group, a partial remission (PR) group (a reduction of at least 50% of the GLD from baseline to last follow-up), and a stable group (stable/showing a reduction lower than 50% of the GLD from baseline to follow up).

RESULTS

One hundred and ten (110) eyes were included. The CR group was composed of 12 eyes (10.9%), while the PR group represented 60.9% of the study population. CR occurred after a mean of 6.0 ± 1.4 months, ranging from 4 to 8 months. Time to regression was significantly lower in eyes naïve to treatment before the study compared with the others (p = 0.022). A significantly lower baseline GLD was detected in the CR group (1292.2 ± 195.6 μm) compared with the PR group (1324.6 ± 135.6 μm) and the stable group (1412.5 ± 110.9 μm) (omnibus p = 0.003).

CONCLUSIONS

Complete regression of the flow signal from the MNV neovascular network documented with OCTA may occur during TE regimens with faricimab. In treatment-naïve eyes, regression occurs earlier during the treatment.

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

PURPOSE

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

DESIGN

Prospective cohort study.

METHODS

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

RESULTS

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

CONCLUSIONS

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

Assessing Choroidal Neovascular Membrane Flow Regression Using Optical Coherence Tomography Angiography After a Single Injection of Faricimab in Age-Related Macular Degeneration: A Case Study

This case study aims to evaluate the regression of the vascular network in a patient with age-related macular degeneration (AMD) following a single injection of faricimab, utilizing optical coherence tomography angiography (OCTA) for detailed assessment. An elderly patient diagnosed with neovascular AMD received a single injection of faricimab, with pre and post-treatment OCTA imaging performed to assess changes in the choroidal neovascular membrane (CNVm) and surrounding retinal structures. OCTA revealed significant regression of the vascular network following the single injection of faricimab, demonstrating a marked reduction in blood flow within the CNV, which corresponded with structural and anatomical improvements in the retina. This case highlights the potential of faricimab to induce rapid regression of CNVm in AMD after a single injection, as observed through OCTA. Furthermore, while current monitoring primarily relies on OCT B-scan structural assessments, the flow dynamics captured by OCTA may play a crucial role in future treatment monitoring and therapeutic strategies for managing neovascular AMD.

Current trends in the characterization and monitoring of vascular response to cancer therapy

Tumor vascular physiology is an important determinant of disease progression as well as the therapeutic outcome of cancer treatment. Angiogenesis or the lack of it provides crucial information about the tumor's blood supply and therefore can be used as an index for cancer growth and progression. While standalone anti-angiogenic therapy demonstrated limited therapeutic benefits, its combination with chemotherapeutic agents improved the overall survival of cancer patients. This could be attributed to the effect of vascular normalization, a dynamic process that temporarily reverts abnormal vasculature to the normal phenotype maximizing the delivery and intratumor distribution of chemotherapeutic agents. Longitudinal monitoring of vascular changes following antiangiogenic therapy can indicate an optimal window for drug administration and estimate the potential outcome of treatment. This review primarily focuses on the status of various imaging modalities used for the longitudinal characterization of vascular changes before and after anti-angiogenic therapies and their clinical prospects.

Role of Plasma Angiopoietin-1 and VEGF Levels as Potential Biomarkers in Chronic Central Serous Chorioretinopathy with Macular Neovascularization

To evaluate the plasma levels of angiopoietin-1 and vascular endothelial growth factor (VEGF) and their association with macular neovascularization (MNV) in patients with chronic central serous chorioretinopathy (cCSC). Correlations between plasma cytokine levels, CSC duration, and mean choroidal thickness (CT) were also investigated. Of the 59 patients with cCSC, 10 patients with MNV secondary to cCSC and 10 patients with cCSC without MNV were enrolled in the study. The control group included 15 healthy volunteers matched for age, sex, smoking status, and comorbidities. Chronic CSC was diagnosed based on typical findings on swept-source optical coherence tomography (OCT), fundus fluorescein angiography, and indocyanine green angiography. Additionally, all patients underwent OCT angiography to help detect MNV. Plasma angiopoietin-1 and VEGF levels were assessed using multiplex immunoassay. The plasma angiopoietin-1 levels differed between the 3 groups (p = 0.005). The angiopoietin-1 levels were lower in patients with cCSC with MNV than in controls (p = 0.006). There were no differences in the plasma VEGF levels between all the 3 groups (p = 0.329). The VEGF levels were negatively correlated with mean CT in cCSC patients with MNV (rho = -0.683, p = 0.042) but correlated positively with disease duration in patients with cCSC without MNV (rho = 0.886, p = 0.003). Our study confirms that MNV is a common complication of cCSC and provides new insights into the role of angiopoietin-1 in cCSC and MNV. Reduced angiopoietin-1 levels in cCSC patients, regardless of MNV status, highlight the importance of the Ang-Tie2 pathway in disease pathogenesis and may point to new therapeutic targets and future novel treatments to improve the management of these patients.

Factors Affecting Disease Stability After Intravitreal Brolucizumab Injection for Refractory Neovascular Age-Related Macular Degeneration

INTRODUCTION

The purpose of this study is to identify the factors affecting neovascular age-related macular degeneration (nAMD) disease stability after brolucizumab treatment.

METHODS

We retrospectively analyzed the medical records of 31 patients (31 eyes) with recalcitrant nAMD who were switched to brolucizumab after conventional anti-vascular endothelial growth factor (VEGF) treatment. We divided patients into two groups by treatment extension (TE) period: group 1 with TE < 12 weeks (N = 16) and group 2 with TE ≥ 12 weeks (N = 15). We compared outcomes between the groups at 2, 4, 8, and 12 weeks, including morphological characteristics of choroidal neovascularization (CNV). Logistic regression analysis identified factors associated with TE ≥ 12 weeks.

RESULTS

Group 2 had a significantly greater proportion of patients with dry macula (subretinal and intraretinal fluids absent) than group 1 (60 vs. 12.5%) at 2 weeks (P < 0.05). Best-corrected visual acuity (BCVA) and subfoveal choroidal thickness (SFCT) did not differ significantly between groups at all timepoints. Central subfield retinal thickness (CST) was significantly lower in group 2 at 2 (237.1 vs. 280.8 μm; P < 0.05), 4 (224.0 vs. 262.9 μm; P < 0.05), and 8 weeks (216.8 vs. 331.1 μm; P < 0.05). Group 2 had less vessel area (0.63 vs. 1.27 mm2; P < 0.05) and total vessel length (0.22 vs. 0.42 mm; P < 0.05). Choriocapillaris flow deficit (CCFd) was significantly lower in group 2 (42.7 vs. 48.2%; P < 0.05). Dry macula at 2 weeks (odds ratio [OR] = 8.3; P < 0.05) and a lower CCFd (OR = 0.73; P < 0.05) were associated with TE ≥ 12 weeks.

CONCLUSIONS

Early fluid-free status after switching to brolucizumab and choriocapillary function around CNV were prognostic factors for disease stability in nAMD refractory to anti-VEGF treatment.

Efficacy and Durability of Faricimab in Naïve Eyes with Neovascular Age-Related Macular Degeneration

INTRODUCTION

The aim of the study was to evaluate functional and anatomical changes in patients with neovascular age-related macular degeneration (nAMD) treated with a loading dose of faricimab intravitreal injections (IVIs).

METHODS

Eighteen eyes of 18 patients with active macular neovascularization and nAMD were enrolled at the Ophthalmology Clinic of University G. D'Annunzio, Chieti-Pescara, Italy. All patients were scheduled for faricimab IVI as per label. Enrolled patients underwent complete ophthalmic evaluation, including optical coherence tomography, fluorescein angiography, and indocyanine green angiography. All measurements were evaluated at baseline (T0) and then monthly up to week 20 (T4). Main outcome measures were changes in best-corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal choroidal thickness (SFCT), pigment epithelial detachments (PEDs) presence and maximum height (PED-MH), intraretinal fluid (IRF) presence, subfoveal subretinal fluid (SSRF) presence and thickness.

RESULTS

BCVA improved and CMT reduced significantly during follow-up (p < 0.001). In addition, SFCT decreased significantly (p = 0.031). Between T0 and T4, SSRF presence reduced from 55.6 to 16.7% (p = 0.045); IRF presence changed from 50 to 22.2%, respectively (p = 0.074). PED-MH was reduced in 58.8% of patients at T4. At week 20, 72.3% of patients were in the q12/q16 interval.

CONCLUSION

Faricimab showed efficacy in the treatment of naïve nAMD patients with an improvement of anatomical and functional parameters and a treatment interval after the loading phase equal or greater than 12 weeks in the majority of patients.

Quantitative Evaluation of Type 1 and Type 2 Choroidal Neovascularization Components Under Treatment With Projection-Resolved OCT Angiography

Purpose

To evaluate the response of type 1 and type 2 macular neovascularization (MNV) components under anti-vascular endothelial growth factor (VEGF) treatment in age-related macular degeneration (AMD) using projection-resolved optical coherence tomography angiography (PR-OCTA).

Methods

This retrospective study included eyes with treatment-naïve exudative AMD treated with anti-VEGF injections under a pro re nata (PRN) protocol over 1 year. Two-dimensional MNV areas and three-dimensional MNV volumes were derived from macular PR-OCTA scans using an automated convolutional neural network. MNV was detected as flow signal within the outer retinal slab. Type 1 components and type 2 components were analyzed separately.

Results

Of 17 enrolled eyes, 12 eyes were pure type 1 MNV and five eyes were type 2 MNV. In eyes with pure type 1, the total (sum of type 1 and type 2 components) MNV area and volume did not change from baseline to 6 months or 12 months (P > 0.05). In eyes with type 2 MNV, the total MNV area significantly decreased from the baseline to 6 months (P = 0.0074) and 12 months (P = 0.014). The total type 2 MNV volume also decreased from baseline visit to visits at 6 months and at 12 months, nearing statistical signifiicance (P = 0.061 and P = 0.074). In eyes with type 2 MNV, the type 1 component increased from 0.093 mm2 to 0.30 mm2 (P = 0.058), and the type 2 component decreased from 0.37 mm2 at 6 months to 0 at 12 months (P = 0.0087).

Conclusions

Type 1 and type 2 MNV may have different response under PRN anti-VEGF treatment over 1 year.

Subretinal transient hyporeflectivity in neovascular age-related macular degeneration and its response to a loading phase of aflibercept: PRECISE report 4

PURPOSE

To describe the prevalence of subretinal transient hyporeflectivity (STHR) in exudative neovascular age-related macular degeneration (nAMD) and its response to a loading phase of aflibercept.

METHODS

Optical coherence tomography (OCT) scans of treatment-naïve nAMD patients captured at baseline and after a loading phase of aflibercept were graded for presence of STHR, defined as a small, well-defined, round, subretinal, hyporeflective area, delimited between the ellipsoid zone (EZ) and the retinal pigmented epithelium/Bruch membrane complex. OCT parameters recorded were macular neovascularisation (MNV) subtypes, location of retinal fluids (subretinal fluid, SRF and intraretinal fluid, IRF), central retinal and choroidal thickness. Response was defined as absence of IRF and SRF. Factors associated with completely resolved STHR versus persistent STHR post-loading phase were compared.

RESULTS

2039 eyes of 1901 patients were analysed. STHR was observed in 79 eyes of 78 patients, with an estimated prevalence of 3.87% (95% CI 3.08-4.81%). STHR were seen in 44 type 1 MNV (56%), 27 with type 2 (34%), and 8 with type 3 (10%). At baseline, a total of 303 STHR were present, ranging between 1-22 per eye. The total number of STHR reduced significantly after the loading phase to 173 (p = 0.002). Complete disappearance of STHR was seen in 44 eyes (56%) and persistent STHR in the rest (44%).

CONCLUSIONS

STHR may represent a marker of low-grade exudation in nAMD eyes with good response to a loading phase of aflibercept. However, its potential role as an independent nAMD activity biomarker is limited as most resolve after the loading phase.

Linking disease activity with optical coherence tomography angiography in neovascular age related macular degeneration using artificial intelligence

To investigate quantitative associations between AI-assessed disease activity and optical coherence tomography angiography (OCTA)-derived parameters in patients with neovascular age-related macular degeneration (nAMD) undergoing anti-VEGF therapy. OCTA and SD-OCT images obtained from multicenter, randomized study data were evaluated. A deep learning algorithm (RetInSight) was used to detect and quantify macular fluid on SD-OCT. Mixed effects models were applied to evaluate correlations between fluid volumes, macular neovascularization (MNV)-type and OCTA-derived MNV parameters; lesion size (LS) and vessel area (NVA). 230 patients were included. A significant positive correlation was observed between SRF and NVA (estimate = 199.8 nl/mm2, p = 0.023), while a non-significant but negative correlation was found between SRF and LS (estimate = - 71.3 nl/mm2, p = 0.126). The presence of Type I and Type II MNV was associated with significantly less intraretinal fluid (IRF) compared to Type III MNV (estimate type I:- 52.1 nl, p = 0.019; estimate type II:- 51.7 nl, p = 0.021). A significant correlation was observed between pigment epithelial detachment (PED) and the interaction between NVA and LS (estimate:28.97 nl/mm2; p = 0.012). Residual IRF at week 12 significantly correlated to baseline NVA (estimate:38.1 nl/mm2; p = 0.015) and LS (estimate:- 22.6 nl/mm2; p = 0.012). Fluid in different compartments demonstrated disparate associations with MNV OCTA features. While IRF at baseline was most pronounced in type III MNV, residual IRF was driven by neovascular MNV characteristics. Greater NVA in proportion to LS was associated with higher amounts of SRF and PED. The correlation between these parameters may represent MNV maturation and can be used as a biomarker for resolution of disease activity. AI-based OCT analysis allows for a deeper understanding of neovascular disease in AMD and the potential to adjust therapeutic strategies to optimize outcomes through precision medicine.

Optical coherence tomography angiography in neovascular age-related macular degeneration: comprehensive review of advancements and future perspective

Optical coherence tomography angiography (OCTA) holds promise in enhancing the care of various retinal vascular diseases, including neovascular age-related macular degeneration (nAMD). Given nAMD's vascular nature and the distinct vasculature of macular neovascularization (MNV), detailed analysis is expected to gain significance. Research in artificial intelligence (AI) indicates that en-face OCTA views may offer superior predictive capabilities than spectral domain optical coherence tomography (SD-OCT) images, highlighting the necessity to identify key vascular parameters. Analyzing vasculature could facilitate distinguishing MNV subtypes and refining diagnosis. Future studies correlating OCTA parameters with clinical data might prompt a revised classification system. However, the combined utilization of qualitative and quantitative OCTA biomarkers to enhance the accuracy of diagnosing disease activity remains underdeveloped. Discrepancies persist regarding the optimal biomarker for indicating an active lesion, warranting comprehensive prospective studies for validation. AI holds potential in extracting valuable insights from the vast datasets within OCTA, enabling researchers and clinicians to fully exploit its OCTA imaging capabilities. Nevertheless, challenges pertaining to data quantity and quality pose significant obstacles to AI advancement in this field. As OCTA gains traction in clinical practice and data volume increases, AI-driven analysis is expected to further augment diagnostic capabilities.

Pachychoroid Spectrum Disease: Comparison of Patients with Central Serous Chorioretinopathy Complicated with Pachychoroid Neovasculopathy

PURPOSE

This study aimed to determine the incidence and visual outcomes of pachychoroid neovasculopathy (PNV) in patients initially diagnosed with central serous chorioretinopathy (CSC).

METHODS

In this study, 144 patients aged 20 to 55 years with treatment-naive chronic CSC, defined as the persistence of subretinal fluid (SRF) for ≥6 months, were retrospectively enrolled. Patients with PNV at the initial evaluation were categorized as group 1, whereas those who developed new-onset PNV during follow-up were categorized as group 2. Patients without PNV until the end of the follow-up were categorized as group 3.

RESULTS

Over a mean follow-up period of 49.9 ± 39.9 months, new-onset PNV was diagnosed in 11.8% of patients with CSC. The time taken to reach the initial resolution was longest in group 1 (group 1, 11.13 ± 10.70 months; group 2, 8.14 ± 7.90 months; group 3, 7.32 ± 9.55 months), although these differences were not statistically significant. The numbers of injections needed to achieve initial resolution were 3.76 ± 5.90, 1.64 ± 2.06, and 1.74 ± 4.33 in groups 1, 2, and 3, respectively, with no significant differences. SRF recurrence was recorded in seven patients (29.2%) in group 1, nine (64.3%) in group 2, and 28 (26.7%) in group 3. The recurrence rates were significantly higher in group 2 than those in group 1 or 3. At the end of the follow-up period, significant improvements in best-corrected visual acuity were achieved in groups 1 and 3, compared with baseline, but not in group 2.

CONCLUSIONS

Patients with chronic CSC with new-onset PNV exhibited higher SRF recurrence and worse visual outcomes compared to those with initial PNV or those with chronic CSC without PNV. Our study emphasizes the importance of routine screening for prompt diagnoses of new-onset PNV in individuals with chronic CSC.

Developing quantitative analysis program of blood flow velocity according to vessel diameter for neovascular age-related macular degeneration using OCTA-VISTA

This study aimed to develop a quantitative analysis program of blood flow velocity by vessel diameter in neovascular age-related macular degeneration (nAMD) subjects using high-speed swept-source optical coherence tomography angiography. This retrospective, observational, cross-sectional study included 10 eyes of healthy volunteers and 4 eyes of patients with representative nAMD. Novel scan patterns and variable interscan time analysis were utilized to measure the flow parameter, a surrogate marker of blood flow velocity, by vessel diameter within different depths. Detected vessels at superficial and deep as well as outer retinal regions were categorized into three vessel diameters (major vessels (> 40 μm), medium vessels (20-40 μm), and capillaries (< 20 μm)). The flow parameter increased with enlarged vessel diameter in all participants at superficial and deep layer. All nAMD subjects, except for type 3 macular neovascularization (MNV), contained a structure dominated by medium vessels at outer retinal region. The mean flow parameter at outer retinal region was type 1 MNV (1.46 ms-1), type 1 + 2 MNV (0.98 ms-1), and polypoidal choroidal vasculopathy, including branching vascular networks (1.46 ms-1). This program provides the possibility to extract the blood flow information at different depths by vessel diameter types, which is considered to be useful tool for evaluating nAMD pathology and activity.

Predictive factors of age-related macular degeneration with poor response to three loading doses of anti-vascular endothelial growth factor

PURPOSE

To evaluate the predictive factors of neovascular age-related macular degeneration (nAMD) with poor response to three loading doses of intravitreal bevacizumab (IVB).

METHODS

A retrospective cohort study was performed on nAMD patients three loading IVB initial treatment. The patients were divided into two groups, without residual fluid on optical coherence tomography (OCT) images (Group 1) and with residual fluid (Group 2). Demographic data, OCT findings, and morphological features of macular neovascularization (MNV) in optical coherence tomography angiography (OCTA) were recorded.

RESULTS

The study included one hundred thirty-six eyes of 120 patients (Group 1: n = 66 eyes, Group 2: n = 70 eyes). Central macular thickness, presence of intraretinal fluid, subretinal fluid, hyperreflective foci-band, pigment epithelial detachment (PED), and prechoroidal cleft were similar between the two groups. Pre-injection central choroidal thickness (CCT) was 214.17 ± 50.28 µm in Group 1 and 247.40 ± 60.55 µm in Group 2 (p = 0.021). PED width (p = 0.028) and PED area (p = 0.042) were statistically significantly higher in Group 1. When the morphology of MNV in OCTA was examined, branching (p = 0.736), loops (p = 0.442), peripheral arcade (p = 0.600), hypointense halo (p = 0.779), sea fan (p = 0.250), medusa (p = 0.255), pruned vascular tree pattern (p = 0.148), capillary fringe (p = 0.683) were similar in both groups. The presence of a closed circuit pattern was significantly higher in Group 2 (p = 0.028).

CONCLUSION

Initial CCT and closed circuit pattern MNV were higher in IVB-resistant cases. It was observed that PEDs with large bases and areas responded significantly better to loading therapy. The presence of a closed-circuit pattern was an independent risk factor for poor response to loading therapy. Retrospectively registered.

REGISTRATION NUMBER

2011-KAEK-25 2023/05-08.

MORPHOLOGICAL BIOMARKERS PREDICTING EXUDATIVE CONVERSION IN TYPE 1 NONEXUDATIVE MACULAR NEOVASCULARIZATION USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To investigate the incidence and morphological biomarkers to predict the exudative conversion in eyes with type 1 nonexudative macular neovascularization using swept-source optical coherence tomography angiography.

METHODS

Macular neovascularizations were detected using the retinal pigment epithelium-to-retinal pigment epithelium-fit slab of swept-source optical coherence tomography angiography scan. Depending on whether exudation developed within a year, the eyes were divided into two groups: active and silent. Qualitative and quantitative optical coherence tomography angiography parameters of the two groups were evaluated to discriminate the biomarkers associated with exudative conversion.

RESULTS

Of the 40 eyes, nine developed exudation within 1 year (incidence rate 22.5%). The active group exhibited a significantly higher "anastomosis and loops" pattern, greater "vessel density," increased "junction density," fewer "number of end points," and lower "lacunarity" compared with the silent group. "Anastomosis and loops" and higher "vessel density" were correlated with the active group in multivariate analyses. A predictive model combining these biomarkers achieved 95% accuracy in predicting exudative conversion.

CONCLUSION

At 12 months, the risk of exudation was 22.5%, and "anastomosis and loops" and "vessel density" were useful optical coherence tomography angiography biomarkers for predicting exudative conversion in eyes with type 1 nonexudative macular neovascularization. For eyes with a high risk of exudative conversion, more frequent follow-up is recommended.

Exploring Current Molecular Targets in the Treatment of Neovascular Age-Related Macular Degeneration toward the Perspective of Long-Term Agents

Long-lasting anti-vascular endothelial growth factor (anti-VEGF) agents have become an option to reduce treatment frequency, with ongoing research exploring optimal responses and safety profiles. This review delves into molecular targets, pharmacological aspects, and strategies for achieving effective and enduring disease control in neovascular age-related macular degeneration (AMD). The molecular pathways involved in macular neovascularization, including angiogenesis and arteriogenesis, are explored. VEGF, PlGF, Ang-1, and Ang-2 play crucial roles in regulating angiogenesis, influencing vessel growth, maturation, and stability. The complex interplay of these factors, along with growth factors like TGFβ and bFGF, contributes to the pathogenesis of neovascular membranes. Current anti-VEGF therapies, including bevacizumab, ranibizumab, aflibercept, brolucizumab, and faricimab, are discussed with a focus on their pharmacokinetics and clinical applications. Strategies to achieve sustained disease control in AMD involve smaller molecules, increased drug dosages, and novel formulations. This narrative review provides a comprehensive overview of the molecular targets and pharmacological aspects of neovascular AMD treatment.

Volume-rendering three-dimensional image analysis of macular neovascularization in age-related macular degeneration

BACKGROUND

To visualize and investigate the three-dimensional (3D) images of macular neovascularization (MNV) in eyes with neovascular age-related macular degeneration using optical coherence tomography angiography (OCTA) according to the treatment response to intravitreal aflibercept injection (IVI).

METHODS

OCTA images at baseline and 12 weeks (after three loading IVIs) were retrospectively reconstructed as 3D images for patients with type 1 and 2 MNV treated with the "pro-re-nata" regimen. The fluid-free and persistent fluid groups were divided according to the presence of subretinal and intraretinal fluid at 12 weeks after treatment. Using reconstructed 3D images of MNV, the volume, average volume per slice, and z-axis of the volumetric structure were evaluated.

RESULTS

Twenty-three and nine were classified into the fluid-free and persistent fluid groups, respectively. The MNV volume decreased significantly from baseline to 12 weeks in the fluid-free group (p = 0.005), not in the persistent fluid group (p = 0.250). The average volume of MNV per slice at 12 weeks correlated with the persistent fluid group in both the univariate and multivariate analyses (p = 0.034, p = 0.039, Exp [B] = 14.005).

CONCLUSIONS

This study may provide a perspective on vascular volumetric changes of MNV according to treatment response.

Treatment Strategies for Anti-VEGF Resistance in Neovascular Age-Related Macular Degeneration by Targeting Arteriolar Choroidal Neovascularization

Despite extensive use of intravitreal anti-vascular endothelial growth factor (anti-VEGF) biologics for over a decade, neovascular age-related macular degeneration (nAMD) or choroidal neovascularization (CNV) continues to be a major cause of irreversible vision loss in developed countries. Many nAMD patients demonstrate persistent disease activity or experience declining responses over time despite anti-VEGF treatment. The underlying mechanisms of anti-VEGF resistance are poorly understood, and no effective treatment strategies are available to date. Here we review evidence from animal models and clinical studies that supports the roles of neovascular remodeling and arteriolar CNV formation in anti-VEGF resistance. Cholesterol dysregulation, inflammation, and ensuing macrophage activation are critically involved in arteriolar CNV formation and anti-VEGF resistance. Combination therapy by neutralizing VEGF and enhancing cholesterol removal from macrophages is a promising strategy to combat anti-VEGF resistance in CNV.

Features of optical coherence tomography angiography in age-related macular degeneration with residual fluid after three loading doses of aflibercept

BACKGROUND

To identify the macular neovascularization (MNV) features in exudative age-related macular degeneration (AMD) patients who exhibited residual fluid after receiving three loading doses of aflibercept.

METHODS

Patients were classified into two groups: Group 1, which did not exhibit intraretinal fluid (IRF) and subretinal fluid (SRF), and Group 2, which did exhibit IRF and/or SRF. Optical coherence tomography angiography (OCTA) features were assessed and compared between the groups.

RESULTS

A total of 101 eyes were enrolled; 65 for Group 1 and 36 for Group 2. No significant differences were found in baseline MNV size (2.94 ± 2.51 µm2 vs. 2.22 ± 2.26 µm2, P = 0.178) or vessel density (47.1 ± 15.4 % vs. 41.3 ± 10.5%, P = 0.052) between Groups 1 and 2. There were significant differences in the presence of loops (52.3% vs. 75%, P = 0.026) and peripheral arcades (29.2% vs. 55.6%, P < 0.001) at baseline between the two groups. In Group 1, there was a significant reduction in the presence of branching (P < 0.001) and loops (P = 0.016) after treatment. In Group 2, only the presence of branching decreased significantly (P < 0.001) after treatment. Multivariable analysis revealed that the presence of a peripheral arcade (B = 4.77, P = 0.001) was significantly associated with residual fluid.

CONCLUSIONS

Although responding to treatment, the presence of loops and peripheral arcades in exudative AMD patients may contribute to residual fluid following the three loading doses of aflibercept. The peripheral arcade, in particular, may play a more significant role in the presence of residual fluid.

Morphological changes of macular neovascularization during long-term anti-VEGF-therapy in neovascular age-related macular degeneration

PURPOSE

To analyze the morphological changes of macular neovascularization (MNV) in exudative neovascular age-related macular degeneration under long-term intravitreal anti-vascular endothelial growth factor (VEGF) therapy in a retrospective cohort study.

METHODS AND PATIENTS

We evaluated 143 nAMD eyes of 94 patients (31 male, 63 female; initial age 55-97 y, mean age 75.9 ± 7.5 y), who started anti-VEGF therapy (IVAN pro re nata (PRN) protocol) between 2009-2018 and received ongoing therapy until the last recorded visit (mean follow-up 5.3 ± 2.9 y, range 1-14 y). The mean total number of injections was 33.3 ± 19.8 with 7.0 ± 2.3 injections/year. MNV size and, if present, associated complete retinal pigment epithelium (RPE) and outer retina atrophy (cRORA) size were measured on optical coherence tomography (OCT) volume scans at the initial visit and for each year of follow-up. MNV and cRORA were identified on B-scans and their respective borders were manually transposed onto the en-face near infrared image and measured in mm2.

RESULTS

MNV enlarged through follow-up, with a mean growth rate of 1.24 mm2 / year. The mean growth in MNV size was independent of initial MNV size, age, gender, MNV subtypes or number of injections per year. Nevertheless, a great interindividual variation in size and growth was observed. cRORA developed in association with increasing MNV size and its incidence increased linearly over follow-up. cRORA lesions also showed continuous growth by a rate of 1.22 mm2 / year.

CONCLUSIONS

Despite frequent long-term anti-VEGF therapy, we observed ongoing MNV growth. This is consistent with the concept that the development of MNV may be a physiological biological repair mechanism to preserve RPE and photoreceptor function, provided hyperpermeability and fluid exudation are controlled. Whether recurring low VEGF levels or other factors are responsible for MNV growth remains controversial.

Intravitreal Brolucizumab for Pachychoroid Neovasculopathy Associated With Chronic Central Serous Chorioretinopathy

Purpose

To evaluate the anatomical and functional outcomes of intravitreal brolucizumab in eyes with chronic central serous chorioretinopathy complicated by pachychoroid neovasculopathy.

Methods

Retrospective analysis of 34 eyes treated with intravitreal brolucizumab. Twenty-five eyes (73.5%) had been treated with other anti-vascular endothelial growth factor agents before switching to brolucizumab, whereas nine eyes were naïve. Outcome measures included the change of central foveal thickness and subfoveal choroidal thickness, evaluation of sub/intraretinal fluid on optical coherence tomography, and change in best-corrected visual acuity.

Results

Before starting brolucizumab, 23 eyes showed subretinal fluid, 8 both subretinal and intraretinal fluid, and 3 intraretinal fluid only. At the last visit, 22 eyes (64.7%) showed complete reabsorption of both intraretinal and subretinal fluid, whereas subretinal fluid was still present in 8 eyes (23.5%), and both intraretinal and subretinal fluid in 4 eyes (11.8%). The mean number of brolucizumab injections required to achieve complete fluid reabsorption was 2.8 ± 1.8. central foveal thickness decreased from 317.8 ± 109.3 µm to 239.8 ± 74.8 µm (P = 0.0005) and subfoveal choroidal thickness decreased from 399.3 ± 86.2 µm to 355.5 ± 92.7 µm at the end of the follow-up period (P = 0.0008). The mean logarithm of the minimum angle of resolution best-corrected visual acuity improved from 0.4 ± 0.2 to 0.3 ± 0.2 at 1 month after the first injection and remained stable at the same values at the end of the follow-up period (P = 0.04).

Conclusions

Intravitreal brolucizumab is effective for the treatment of naïve and recalcitrant pachychoroid neovasculopathy.

Translational Relevance

Intravitreal brolucizumab may represent an option in patients with pachychoroid neovasculopathy complicating chronic central serous chorioretinopathy.

Quantitative response of macular neovascularisation to loading phase of aflibercept in neovascular age-related macular degeneration

PURPOSE

To evaluate quantitative morphological changes in macular neovascularisation (MNV) network after aflibercept therapy in neovascular age-related macular degeneration (nAMD) patients.

METHODS

Consecutive treatment-naïve patients with optical coherence tomography (OCT) angiography confirmed MNV due to nAMD who completed a loading phase of intravitreal aflibercept injections. A quantitative analysis of the vascular network remodelling was performed using a computational software (Angiotool).

RESULTS

A total of 53 eyes of 52 patients were included in the analysis. The total MNV area decreased significantly after three aflibercept injections (p = 0.003). Total vessel area and vessel density decreased respectively of 20% and 12% at V3 (p < 0.001 in both cases). Other parameters that reduced significantly were total vessel length, average vessel length and density of vascular junctions (p = 0.018, p = 0.002, and p = 0.044, respectively). The number of vascular endpoints (p = 0.001) and lacunarity (p = 0.011) increased significantly, whilst the number of vascular junctions did not vary significantly (p = 0.068). Changes in vascular metrics were predominantly driven by MNV type 1 and 2. No clear relationship was observed between any of the vascular metrics and the macular fluid status.

CONCLUSION

Although objective quantification of vascular parameters showed a significant remodelling of the MNV post-loading phase of aflibercept in type 1 and 2 MNV subtypes, none of the quantified vascular metrics correlated to the macular fluid response. These findings highlight a dissociation of anti-angiogenic and anti-permeability properties of aflibercept therapy during the loading phase.

Endpoints for clinical trials in ophthalmology

With the identification of novel targets, the number of interventional clinical trials in ophthalmology has increased. Visual acuity has for a long time been considered the gold standard endpoint for clinical trials, but in the recent years it became evident that other endpoints are required for many indications including geographic atrophy and inherited retinal disease. In glaucoma the currently available drugs were approved based on their IOP lowering capacity. Some recent findings do, however, indicate that at the same level of IOP reduction, not all drugs have the same effect on visual field progression. For neuroprotection trials in glaucoma, novel surrogate endpoints are required, which may either include functional or structural parameters or a combination of both. A number of potential surrogate endpoints for ophthalmology clinical trials have been identified, but their validation is complicated and requires solid scientific evidence. In this article we summarize candidates for clinical endpoints in ophthalmology with a focus on retinal disease and glaucoma. Functional and structural biomarkers, as well as quality of life measures are discussed, and their potential to serve as endpoints in pivotal trials is critically evaluated.

PREDICTIVE ROLES OF QUANTITATIVE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FEATURES IN PROGNOSIS OF MYOPIC CHOROIDAL NEOVASCULARIZATION

PURPOSE

To explore the predictive roles of the morphologic features of neovascularization in the prognosis of myopic choroidal neovascularization.

METHODS

In this retrospective case series study, quantitative morphologic features of neovascularization were obtained from the optical coherence tomography angiography images. According to the number of anti-vascular endothelial growth factor injections administered within 1 year, the eyes were classified into a stable group (≤2 injections) or an unstable group (>2 injections). Best-corrected visual acuity was recorded before the treatment and at the 1-year follow-up.

RESULTS

Overall, 50 eyes with treatment-naive myopic choroidal neovascularization were included; 26 in the stable group and 24 in the unstable group. Multivariate analysis showed that the eyes in the unstable group were associated with a larger lesion area (odds ratio = 2.596, P = 0.012), higher junction density (odds ratio = 1.611, P = 0.014), and higher end point density (odds ratio = 1.435, P = 0.023).The area under the receiver operating characteristic curve of the multivariate model was 0.865, with 91.7% sensitivity and 65.4% specificity. The final best-corrected visual acuity was significantly correlated with the lesion area (β = 0.152, P = 0.032) after adjusted for age, sex, and baseline best-corrected visual acuity.

CONCLUSION

Lesions with larger areas and higher end point and junction densities tended to have more frequent anti-vascular endothelial growth factor injections and worse visual outcomes in eyes with myopic choroidal neovascularization.

ASSESSMENT AND ROLE OF ARTERY-VEIN COMPLEX IN MYOPIC CHOROIDAL NEOVASCULARIZATION USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

PURPOSE

To analyze the presence of an artery-vein complex (AVC) underneath myopic choroidal neovascularization (mCNV) and to determine its relationship with neovascular activity.

METHODS

Retrospective analysis of 681 eyes from 362 patients with high myopia defined by an axial length of >26 mm using optical coherence tomography (OCT) and OCT angiography imaging. Patients with clinical diagnosis of mCNV and good quality OCT angiography images were then selected. An AVC was defined by the identification of both perforating scleral vessels and dilated choroidal veins under or in contact with the mCNV in the same case. Swept source OCT (SS-OCT) and SS-OCT angiography images (TRITON; Topcon Corporation, Tokyo, Japan) were reviewed to detect AVC in the mCNV area.

RESULTS

Fifty eyes of 49 highly myopic patients with mCNV were analyzed. Eyes with AVC were statistically older (69.95 ± 13.53 vs. 60.83 ± 10.47 years old; P < 0.01), needed less intravitreal injections/year along the follow-up period (0.80 ± 0.62 vs. 1.92 ± 0.17; P < 0.01), and showed less relapses/year (0.58 ± 0.75 vs. 0.46 ± 0.42; P < 0.05) when compared with eyes without AVC. Moreover, eyes with AVC were less likely to relapse during the first year from mCNV activation (n = 5/14 vs. n = 14/16; P < 0.01; P < 0.01). No significant differences were found regarding either axial length (30.55 ± 2.31 vs. 29.65 ± 2.24, P > 0.05) or best-corrected visual acuity (0.4 ± 0.5 vs. 0.4 ± 0.5 Logarithm of the Minimum Angle of Resolution (logMAR), P > 0.05) between groups.

CONCLUSION

AVC complex has an influence over myopic choroidal neovascularization activity resulting in less aggressive neovascular lesions than those with perforating scleral vessels only.

OCT angiography and its retinal biomarkers [Invited]

Optical coherence tomography angiography (OCTA) is a high-resolution, depth-resolved imaging modality with important applications in ophthalmic practice. An extension of structural OCT, OCTA enables non-invasive, high-contrast imaging of retinal and choroidal vasculature that are amenable to quantification. As such, OCTA offers the capability to identify and characterize biomarkers important for clinical practice and therapeutic research. Here, we review new methods for analyzing biomarkers and discuss new insights provided by OCTA.

MMP9-Responsive Graphene Oxide Quantum Dot-Based Nano-in-Micro Drug Delivery System for Combinatorial Therapy of Choroidal Neovascularization

Age-related macular degeneration (AMD), especially wet AMD with choroidal neovascularization (CNV), commonly causes blindness in older patients and disruption of the choroid followed by second-wave injuries, including chronic inflammation, oxidative stress, and excessive matrix metalloproteinase 9 (MMP9) expression. Increased macrophage infiltrate in parallel with microglial activation and MMP9 overexpression on CNV lesions is shown to contribute to the inflammatory process and then enhance pathological ocular angiogenesis. Graphene oxide quantum dots (GOQDs), as natural antioxidants, exert anti-inflammatory effects and minocycline is a specific macrophage/microglial inhibitor that can suppress both macrophage/microglial activation and MMP9 activity. Herein, an MMP9-responsive GOQD-based minocycline-loaded nano-in-micro drug delivery system (C18PGM) is developed by chemically bonding GOQDs to an octadecyl-modified peptide sequence (C18-GVFHQTVS, C18P) that can be specifically cleaved by MMP9. Using a laser-induced CNV mouse model, the prepared C18PGM shows significant MMP9 inhibitory activity and anti-inflammatory action followed by antiangiogenic effects. Moreover, C18PGM combined with antivascular endothelial growth factor antibody bevacizumab markedly increases the antiangiogenesis effect by interfering with the "inflammation-MMP9-angiogenesis" cascade. The prepared C18PGM shows a good safety profile and no obvious ophthalmic or systemic side effects. The results taken together suggest that C18PGM is an effective and novel strategy for combinatorial therapy of CNV.

The Choroidal Vascularity Index Versus Optical Coherence Tomography Angiography in the Evaluation of the Choroid with a Focus on Age-Related Macular Degeneration

The choroid is the most vascularized structure of the eye and it is fundamental for the trophism of the outer retina. Its proper functioning and homeostasis represent key points in maintaining normal retinal physiology. Choroidal alterations may be implicated in the development and progression of numerous pathologies; therefore, in-depth studies using imaging techniques can be of crucial relevance to understanding the pathophysiology of retinal-choroidal diseases. The advent of spectral-domain optical coherence tomography (SDOCT) has enabled the non-invasive study of the choroid in vivo and the most recent development, optical coherence tomography angiography (OCTA), allows for the high-resolution visualization of the choriocapillaris and the choroid in regard to vascularization. The choroidal vascularity index (CVI) is a new parameter calculated on SDOCT scans and is defined as the ratio of the luminal area to the total choroidal area. In this review, a study of the choroid using OCTA and CVI will be evaluated in depth and the pros and cons of these two methods will be analyzed, with a particular focus on age-related macular degeneration.

Optical coherence tomography angiography biomarkers in a bi-monthly maintenance dosing aflibercept in patients with neovascular age-related macular degeneration

PURPOSE

To evaluate the correlations between swept-source optical coherence tomography angiography (SS-OCTA) parameters and clinical outcomes in eyes with neovascular age-related macular degeneration (nAMD) administered a bimonthly intravitreal aflibercept regimen.

METHODS

This prospective, single-arm, interventional study enrolled 33 patients with treatment-naïve nAMD. The eyes received three monthly aflibercept injections followed by five bi-monthly regimens (total 50 weeks). The structural parameters including central subfield thickness (CST) and 5 mm pigment epithelial detachment (PED) volume and microvascular parameters including macular neovascularization (MNV) area, vessel density (VD), and vessel length density (VLD) were recorded every before and 1 week after treatment.

RESULTS

Patients who gained > 5 letters of best-corrected visual acuity (BCVA) from the baseline showed greater decreases in VD and VLD during the loading phase. Patients without recurrent or persistent fluid during the maintenance phase showed greater decreases in CST and 5 mm PED volume after the first injection. The decrease in mean VD during the loading phase was significantly correlated with the final BCVA (r = -0.820, p = 0.004). Moreover, the decrease in mean VLD during the loading phase was significantly correlated with the improvement in the final BCVA (r = -0.726, p = 0.017).

CONCLUSIONS

The decrease in mean VD during the loading phase was significantly negatively correlated with the final BCVA at the last visit. The decrease in mean VLD during the loading phase, mean CST during the loading phase, and the improvement in final BCVA showed significant correlations. Therefore, early changes in OCTA microvascular and OCT structural parameters could help predict clinical outcomes in nAMD.

TRIAL REGISTRATION

The trial was registered with the Clinical Research Information Service (CRIS), which joined the WHO International Clinical Trials Registry Platform (ICTRP) (Registration number: KCT0007375, Date of first trial registration: 10/06/2022).

QUANTIFIED ANASTOMOTIC AREAS OF NEOVASCULARIZATION AS FACTORS ASSOCIATED WITH FREQUENT RECURRENCE IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION

PURPOSE

To investigate the quantitative characteristics of anastomoses of macular neovascularization (MNV) in neovascular age-related macular degeneration using optical coherence tomography angiography according to the frequency of intravitreal injections.

METHODS

Eighty-six eyes of 86 patients treated for neovascular age-related macular degeneration were classified into two groups based on the number of intravitreal injections administered over 12 months: stable (<3) and unstable (≥3). Anastomotic areas were defined as areas surrounded by neighboring vessels in the MNV; their total number, mean area, maximal and minimal diameters (i.e., maximal and minimum Feret diameters), and ratio (Feret aspect ratio) were analyzed in the inner and outer areas of the MNV.

RESULTS

Forty-four and 42 eyes were classified into the stable and unstable groups, respectively. The eyes in the unstable group had larger anastomotic areas with longer minimum Feret diameters and longer perimeters in the outer MNV. In the logistic regression analysis, instability was associated with a larger anastomotic area and a longer minimum Feret diameter in the outer MNV. Multivariate analysis revealed that a longer minimum Feret diameter in the outer MNV was the most significant factor ( P = 0.03).

CONCLUSION

The quantitative characteristics of the anastomotic areas in the MNV might indicate the need for intravitreal injections in patients with neovascular age-related macular degeneration.

OCTA Biomarker Search in Patients with nAMD: Influence of Retinal Fluid on Time-Dependent Biomarker Response

PURPOSE

Previous studies have identified a link between optical coherence tomography (OCT)-derived and OCT angiography (OCTA)-based parameters in patients with neovascular AMD (nAMD); the latter may serve as direct biomarkers for macular neovascularization (MNV) activity. The aim of this study was to assess the individual influence of retinal thickness (RT) as well as intra- and sub-retinal fluid (IRF, SRF) presence on the treatment response over time as assessed by previously identified OCTA-derived MNV vascular parameters.

METHODS

During the first 3 months of anti-VEGF therapy patients were prospectively followed. RT, SRF and IRF were determined from SSOCT/A (PlexElite, Zeiss) images and using the semi-automated AngioTool software, vessel area (VA), total vessel length (TVL), total number of junctions (TNJ), junction density (JD), vessel density (VD) as well as MNV area were exported. IRF and SRF were identified manually on OCT volume scans .The associations between RT, IRF, and SRF and SSOCTA vascular parameters were analyzed using linear mixed models.

RESULTS

31 eyes of 31 patients with treatment-naïve and OCTA-positive nAMD MNV were included in this analysis. VA, TVL, TNJ, and MNV area show a statistically significant change over time in response to anti-VEGF treatment, even after correcting for the presence of SRF, IRF, or RT (all p < 0.05). This is not the case for JD and VD (both p > 0.05).

CONCLUSIONS

OCTA-based parameters VA, TVL, TNJ, and MNVarea show a strong response to anti-VEGF therapy over time, independent of the presence of IRF, SRF or RT. We conclude that the above listed OCTA parameters could contribute to our understanding of MNV biology and to guide individualized treatment in the future.

TRIAL REGISTRY

The authors confirm that all ongoing and related trials are registered. ClinicalTrials.gov Number: NCT02521142.

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.

Correlation of vascular and fluid-related parameters in neovascular age-related macular degeneration using deep learning

PURPOSE

To identify correlations between the vascular characteristics of macular neovascularization (MNV) obtained by optical coherence tomography angiography (OCTA) and distinct retinal fluid volumes in neovascular age-related macular degeneration (nAMD).

METHODS

In this prospective interventional study, 54 patients with treatment-naïve type 1 or 2 nAMD were included and treated with intravitreal aflibercept. At baseline and month 1, each patient underwent a SD-OCT volume scan and volumetric flow scan using a swept-source OCTA. A deep learning algorithm was used to automatically detect and quantify fluid in OCT scans. Angio Tool, a National Cancer Institute algorithm, was used to skeletonize MNV properties and quantify lesion size (LS), vessel area (VA), vessel density (VD), total number of endpoints (TNE), total number of junctions (TNJ), junction density (JD), total vessel length (TVL), average vessel length (AVL) and mean-e-lacunarity (MEL). Subsequently, linear regression models were used to investigate a correlation between OCTA parameters and fluid quantifications.

RESULTS

The median amount of fluid within the central 6-mm EDTRS ring was 173.7 nl at baseline, consisting of 156.6 nl of subretinal fluid (SRF) and 2.3 nl of intraretinal fluid (IRF). Fluid decreased significantly in all compartments to 1.76 nl (SRF) and 0.64 nl (IRF). The investigated MNV parameters did not change significantly after the first treatment. There was no significant correlation between MNV parameters and relative fluid decrease after anti-VEGF treatment. Baseline fluid correlated statistically significant but weakly with TNE (p = 0.002, R²  = 0.17), SRF with TVL (p = 0.04, R²  = 0.08), VD (p = 0.046, R²  = 0.08), TNE (p = 0.001, R²  = 0.20) and LS (p = 0.033, R²  = 0.09). IRF correlated with VA (p = 0.042, R²  = 0.08).The amount of IRF at month 1 correlated significantly but weakly with VD (p = 0.036, R²  = 0.08), JD (p = 0.019, R²  = 0.10) and MEL (p = 0.005, R²  = 0.14).

CONCLUSION

Macular neovascularization parameters at baseline and month 1 played only a minor role in the exudation process in nAMD. None of the MNV parameters were correlated with the treatment response.

Optical coherence tomography angiography patterns of type 1 macular neovascularization in age-related macular degeneration patients

PURPOSE

To compare morphologic characteristics of type 1 macular neovascularization (MNV) flow pattern in treatment-naïve and previously treated patients with age-related macular degeneration (AMD) as assessed by optical coherence tomography angiography (OCTA).

STUDY DESIGN

Cross-sectional study.

MATERIALS AND METHODS

Macular OCT angiography images were acquired using RTVue XR Avanti with AngioVue. Distinct morphologic biomarkers and quantifiable features of the neovascular membranes were studied on en-face projection images comparing treatment-naïve and previously treated patients.

RESULTS

The study included 68 eyes of 58 patients. Among them, 24 eyes were treatment-naïve, and the remaining eyes had received a mean of 19.6 injections. Immature lesions were more associated with treatment-naïve eyes and hyper-mature lesions were associated with previously treated eyes (p = 0.005). Tangle pattern was associated with treatment-naïve eyes (p = 0.013), whereas mature core vessels and sea fan pattern were associated more with previously treated eyes (p = 0.001 and p = 0.044, respectively). Vascular density of the neovascular membrane was higher in the treatment-naïve group (p = 0.036) and the average MNV area was similar between the 2 groups (p = 0.683).

CONCLUSIONS

Based on OCTA, morphologic biomarkers of type 1 MNV might be an indication of previous treatment. The MNV pattern can improve our understanding of its maturation under anti-VEGF treatment and might be valuable to better guide therapeutic decisions and provide more personalized care to patients with AMD.

Predictive role of optical coherence tomography angiography for exudation recurrence in patients with type 1 neovascular age-related macular degeneration treated with pro-re-nata protocol

OBJECTIVES

We sought to identify the consecutive changes and predictive features for exudation recurrence in macular neovascularization (MNV) using optical coherence tomography angiography (OCTA) in type 1 neovascular age-related macular degeneration (NVAMD).

METHODS

A total of 291 OCTA images in consecutive visit of 45 patients newly diagnosed with type 1 NMV and treated with three loading intravitreal anti-vascular endothelial growth factor injections (IVIs) and a pro-re-nata (PRN) therapy regimen were analysed. Quantitative features of OCTA included the MNV area, MNV length, total number of endpoints (open-ended vessels) and junctions (internal branching) using AngioTool. Two subgroups were divided according to exudation recurrence time from the third IVI (group 1: ≤3 months vs. group 2: >3 months).

RESULTS

The area, length, number of total junctions, and endpoints decreased during three loading IVIs and increased at exudation recurrence (all p < 0.05). In a subgroup analysis of consecutive OCTA images, the number of total endpoints increased at two months prior to exudate recurrence in group 2 (the late recurrence group, p = 0.020). A higher total number of endpoints of MNV at baseline were found to be related with group 1 (early recurrence, p = 0.020 and 0.012 in univariate and multivariate regression analyses).

CONCLUSIONS

The MNV with higher open-ended vessels at the lesion periphery at baseline might be expected to show earlier recurrence of exudation after loading IVIs. By observing the number of open-ended vessels in consecutive OCTA images, exudation recurrence could be predicted.

[Prognosis criteria of optical coherence tomography angiography for the long-term efficacy of anti-VEGF therapy of neovascular age-related macular degeneration]

PURPOSE

The study aimed to determine the most significant optical coherence tomography angiography (OCTA) parameters in terms of predicting anti-VEGF therapy effectiveness during long-term (3-year) follow-up of patients with neovascular age-related macular degeneration (nAMD).

MATERIAL AND METHODS

The study included 122 patients (122 eyes) with mean age of 73.4±6.6 years who were diagnosed with nAMD. Subgroup analysis included 50 patients (50 eyes) with detailed OCT angiography examination of macular neovascularization (MNV) characteristics and their changes in the course of the follow-up, which lasted 144 weeks. All patients were treated by angiogenesis inhibitor (aflibercept 2 mg), most of them - according to Treat-and-Extend protocol.

RESULTS

Treatment response (either 'good' or 'partial') was achieved in all patients, and the proportion of the response types was similar in both types 1 and 2 MNV. Key OCTA parameters associated with the number of injections, as well as morphological and functional response (best-corrected visual acuity, retinal neuroepithelium and pigment epithelium detachment), were vascular network area and MNV area assessed at baseline and three months after treatment initiation. Both of these parameters were closely related in both MNV types during the follow-up. Key parameter with maximum number of clinically significant correlations ('very high' strength, p<0.05) in eyes with 'good' response was MNV area, in eyes with 'partial' response - vascular density and greatest vascular caliber.

CONCLUSIONS

Vascular network area and MNV area assessed at baseline and after three loading doses were determined as the most significant OCTA characteristics for predicting the number of injections and treatment response based on functional and morphological parameters. MNV area was found to be the most clinically significant marker in 'good' response, vascular density and greatest vascular caliber - in 'partial' response.

[Diagnosis and clinical features of non-exudative macular neovascularization]

Macular neovascularization (MNV) is the process of new abnormal blood vessels formation in the choroid and/or retina. The widespread adoption of optical coherence tomography angiography (OCTA) has significantly expanded the possibilities of not only detecting pathological blood flow before the development of exudation and deterioration of visual acuity, but also determining its characteristics. The purpose of this review is to substantiate the criteria for choosing terminology and diagnostic markers of MNV. The term "non-exudative MNV" refers to type 1 neovascularization without intraretinal or subretinal exudation detected on repeated OCT scans in the course of at least 6 months. This type of MNV may include previously untreated, non-exudative membranes with a low tendency to exudate, as well as previously treated membranes that have become inactive or dormant and no longer require anti-angiogenic therapy. The criterion for dividing the non-exudative form of MNV into inactive (with a low growth rate and vascular density (VD) at baseline) and subclinical (with a high growth rate and VD) is the time of its activation, generally recognized as 6 months. The diagnostic criteria is the visualized "double layer" sign on OCT scans (retinal pigment epithelium and Bruch's membrane), as well as patterns of neovascular membranes of varying sizes, morphology and localization on OCTA scans. The cumulative risk of conversion from subclinical to exudative at two years of follow-up is 13.6 times higher than in eyes without detectable neovascularization, which highlights the importance of frequent monitoring in this healthy eye population for early detection of MNV signs.

CHARACTERISTICS OF AGE-RELATED MACULAR DEGENERATION SHOWING A POOR RESPONSE TO THREE LOADING DOSES OF ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR

PURPOSE

To analyze the clinical features of refractory age-related macular degeneration patients associated with the response to three consecutive loading doses of anti-vascular endothelial growth factor.

METHODS

A retrospective chart review was performed on typical exudative age-related macular degeneration patients treated by three consecutive anti-vascular endothelial growth factor injections. The patients were divided into a group without residual fluid on optical coherence tomography images (Group 1) and a group with residual fluid (Group 2). We analyzed qualitative and quantitative morphologic features of optical coherence tomography and optical coherence tomography angiography. We performed univariate and multivariate logistic regression analyses to identify factors associated with the treatment response.

RESULTS

We enrolled a total of 90 patients (Group 1: n = 60, Group 2: n = 30). Under optical coherence tomography, the choroidal thickness differed significantly between groups 1 and 2 (246.60 ± 67.67 vs. 286.90 ± 40.92 µ m, P = 0.001). Under optical coherence tomography angiography, the presence of branching (48.3% vs. 73.3%, P = 0.024), loops (31.7% vs. 66.7%, P = 0.002), and a peripheral arcade (40.0% vs. 76.7%, P = 0.001) differed significantly. Logistic regression analysis showed that the initial CT (B = 0.012; P = 0.007), presence of loops (B = 1.289; P = 0.015), and peripheral arcade (B = 1.483; P = 0.008) significantly affected the anti-vascular endothelial growth factor treatment response.

CONCLUSION

A thicker choroid and the presence of loops and a peripheral arcade were significantly associated with a poorer response to three loading anti-vascular endothelial growth factor injections in typical exudative age-related macular degeneration patients.

Towards a better understanding of non-exudative choroidal and macular neovascularization

Non-exudative macular and choroidal neovascularization (MNV and CNV) usually refers to the entity of treatment-naïve type 1 neovascularization in the absence of associated signs of exudation. Histopathological studies, dating back in the early 70s, identified the presence of non-exudative MNV, but the first clinical report of this finding was in the late 90s using indocyanine green angiography in eyes with age-related macular degeneration (AMD). With more advanced retinal imaging, there has been an ever increasing appreciation of non-exudative MNV associated with AMD and CNV with other macular disorders. However, consensus regarding the exact definition and the clinical management of this entity is lacking. Furthermore, there may be variation in the imaging features and clinical course suggesting that a spectrum of disease may exist. Herein, we review the large body of published work that has provided a better understanding of non-exudative MNV and CNV in the last decade. The prevalence, multimodal imaging features, clinical course, and response to treatment are discussed to elucidate further key insights about this entity. Based on these observations, this review also proposes a new theory about the origin and course of different sub-types of non-exudative MNV/CNV which can have different etiologies and pathways according to the clinical context of disease.

Retinal and Choroidal Ultra-Widefield OCT - Technology, Insights, and Clinical Relevance

As one of the most state-of-the-art procedures for retinal and choroidal imaging, ultra-widefield optical coherence tomography (UWF-OCT) offers significant gains in terms of information pertaining to peripheral retinal lesions and their differential diagnoses. In particular, it enables the presence of minimal accumulations of subretinal fluid to be assessed in detail and then documented. It also enables choroidal expansion of choroidal lesions to be precisely measured. Similar to conventional OCT, its only limitations relate to patient compliance and opacities of the ocular media. While the pupil width is somewhat less important here, the quality of the images is nevertheless better with the patient under medication-induced mydriasis. Used in combination with UWF fundus photography, UWF-OCT is a helpful tool for assessing and monitoring peripheral retinal and choroidal lesions.

Prediction of the short-term efficacy of anti-VEGF therapy for neovascular age-related macular degeneration using optical coherence tomography angiography

Background

To evaluate whether the specific choroidal neovascularization (CNV) characteristics measured using optical coherence tomography angiography (OCTA) can predict the 6-month prognosis of neovascular age-related macular degeneration (nAMD) after anti-vascular endothelial growth factor (anti-VEGF) therapy.

Methods

Patients with type 1, type 2, or mixed-type neovascularization (NV) were prospectively included. Participants underwent an initial loading phase of three consecutive monthly intravitreal injections of Conbercept (0.5 mg) and were switched to a pro re nata (PRN) treatment strategy. OCTA images were evaluated for eyes that underwent follow-up assessments for more than 6 months. CNV lesions were manually segmented, and the CNV area, vessel area, greatest vascular caliber (GVC), and greatest linear dimension (GLD) were compared between responders and non-responders. Two masked graders independently measured the above-mentioned parameters using OCTA, and consistency was assessed using the intraclass correlation coefficient (ICC) values. Multiple logistic regression analysis was performed to evaluate the effect of a 3-month change in the CNV area, GLD, and GVC on the 6-month response to anti-VEGF agents.

Results

Among the 60 eyes of 60 patients with nAMD, 39 were responders and 21 were non-responders. The proportion of CNV types was significantly different between responders and non-responders (P = 0.009). Patients with type 2 or mixed NV seemed more likely to respond to the treatment (28.2% vs. 0.0%, and 30.8% vs. 23.8%, respectively). The change in GVC showed a significant difference between responders (− 4.98 ± 17.17 μm) and non-responders (11.01 ± 14.10 μm) after three monthly intravitreal anti-VEGF injections. Multiple logistic regression analysis showed that only the change in GVC remained significant after controlling for baseline GVC, injection number, and CNV type (adjusted OR = 1.083; P = 0.008).

Conclusions

Type 2 and mixed-type NV were significantly associated with a better response to anti-VEGF therapy. Changes in GVC after 3 months of treatment were significantly associated with a response to anti-VEGF therapy at 6 months.

Combination of AIBP, apoA-I, and Aflibercept Overcomes Anti-VEGF Resistance in Neovascular AMD by Inhibiting Arteriolar Choroidal Neovascularization

Purpose

Anti-VEGF resistance represents a major unmet clinical need in the management of choroidal neovascularization (CNV). We have previously reported that a combination of AIBP, apoA-I, and an anti-VEGF antibody overcomes anti-VEGF resistance in laser-induced CNV in old mice in prevention experiments. The purpose of this work is to conduct a more clinically relevant study to assess the efficacy of the combination of AIBP, apoA-I, and aflibercept in the treatment of anti-VEGF resistance of experimental CNV at different time points after laser photocoagulation.

Methods

To understand the pathobiology of anti-VEGF resistance, we performed comprehensive examinations of the vascular morphology of laser-induced CNV in young mice that are highly responsive to anti-VEGF treatment, and in old mice that are resistant to anti-VEGF therapy by indocyanine green angiography (ICGA), fluorescein angiography (FA), optical coherence tomography (OCT), and Alexa 568 isolectin labeled choroid flatmounts. We examined the efficacy of the combination therapy of AIBP, apoA-I, and aflibercept intravitreally delivered at 2, 4, and 7 days after laser photocoagulation in the treatment of CNV in old mice.

Results

Laser-induced CNV in young and old mice exhibited cardinal features of capillary and arteriolar CNV, respectively. The combination therapy and the aflibercept monotherapy were equally effective in treating capillary CNV in young mice. In old mice, the combination therapy was effective in treating anti-VEGF resistance by potently inhibiting arteriolar CNV, whereas aflibercept monotherapy was ineffective.

Conclusions

Combination therapy of AIBP, apoA-I, and aflibercept overcomes anti-VEGF resistance in experimental CNV in old mice by inhibiting arteriolar CNV.

OCT angiography biomarkers in type 1 choroidal neovascularisation after one year of aflibercept treatment

OBJECTIVE

To assess the activity of biomarkers, through OCT angiography (OCTA), of choroidal neovascularisation (CNV) secondary to age-related macular degeneration (AMD) treated with aflibercept. As secondary endpoints, visual acuity (VA) and the relationship between biomarkers and visual prognosis were also studied.

MATERIAL AND METHODS

Prospective study that examined 33 eyes of 40 naïve patients with type 1 CNV secondary to AMD, who had been treated with aflibercept, according to summary of product characteristics, for one year. The patients were evaluated at the time of diagnosis, and at 4, 8 and 12 months.

RESULTS

The mean VA gain at 12 months was 15.2 ± 3.3 letters. The area of lesion decreased 1.2 ± 1.0 mm2 in the 4th month (P < .0001), remaining stable afterwards. The presence of tiny capillaries, anastomosis and perilesional hypointense halo was reduced by 85%, 70% and 25%, respectively, at 12 months of follow-up. The peripheral vascular arcade changed morphology, from having a leafy appearance to having a sharp appearance in 90% of cases. The size of the lesion and the presence/absence of perilesional hypointense halo were independently associated with the final VA, in such a way that larger lesions and the absence of a perilesional hypointense halo at the baseline visit were associated with less VA gain.

CONCLUSIONS

The OCTA is a useful, non-invasive tool that provides quantitative and qualitative information on the remodelling of the CNV vascular network after antiangiogenic therapy.

Peptide Lv augments intermediate-conductance calcium-dependent potassium channels (KCa3.1) in endothelial cells to promote angiogenesis

Peptide Lv is a small endogenous secretory peptide that is expressed in various tissues and conserved across different species. Patients with diabetic retinopathy, an ocular disease with pathological angiogenesis, have upregulated peptide Lv in their retinas. The pro-angiogenic activity of peptide Lv is in part through promoting vascular endothelial cell (EC) proliferation, migration, and sprouting, but its molecular mechanism is not completely understood. This study aimed to decipher how peptide Lv promotes EC-dependent angiogenesis by using patch-clamp electrophysiological recordings, Western immunoblotting, quantitative PCR, and cell proliferation assays in cultured ECs. Endothelial cells treated with peptide Lv became significantly hyperpolarized, an essential step for EC activation. Treatment with peptide Lv augmented the expression and current densities of the intermediate-conductance calcium-dependent potassium (KCa3.1) channels that contribute to EC hyperpolarization but did not augment other potassium channels. Blocking KCa3.1 attenuated peptide Lv-elicited EC proliferation. These results indicate that peptide Lv-stimulated increases of functional KCa3.1 in ECs contributes to EC activation and EC-dependent angiogenesis.