VASCULAR REMODELING OF CHOROIDAL NEOVASCULARIZATION AFTER ANTI–VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY VISUALIZED ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

Nomogram for predicting short-term response to anti-vascular endothelial growth factor treatment in neovascular age-related macular degeneration: An observational study

BACKGROUND

Anti-vascular endothelial growth factor (anti-VEGF) therapy is critical for managing neovascular age-related macular degeneration (nAMD), but understanding factors influencing treatment efficacy is essential for optimizing patient outcomes.

AIM

To identify the risk factors affecting anti-VEGF treatment efficacy in nAMD and develop a predictive model for short-term response.

METHODS

In this study, 65 eyes of exudative AMD patients after anti-VEGF treatment for ≥ 1 mo were observed using optical coherence tomography angiography. Patients were classified into non-responders (n = 22) and responders (n = 43). Logistic regression was used to determine independent risk factors for treatment response. A predictive model was created using the Akaike Information Criterion, and its performance was assessed with the area under the receiver operating characteristic curve, calibration curves, and decision curve analysis (DCA) with 500 bootstrap re-samples.

RESULTS

Multivariable logistic regression analysis identified the number of junction voxels [odds ratio = 0.997, 95% confidence interval (CI): 0.993-0.999, P = 0.010] as an independent predictor of positive anti-VEGF treatment outcomes. The predictive model incorporating the fractal dimension, number of junction voxels, and longest shortest path, achieved an area under the curve of 0.753 (95%CI: 0.622-0.873). Calibration curves confirmed a high agreement between predicted and actual outcomes, and DCA validated the model's clinical utility.

CONCLUSION

The predictive model effectively forecasts 1-mo therapeutic outcomes for nAMD patients undergoing anti-VEGF therapy, enhancing personalized treatment planning.

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.

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.

DEEP LEARNING FOR AUTOMATIC PREDICTION OF EARLY ACTIVATION OF TREATMENT-NAIVE NONEXUDATIVE MACULAR NEOVASCULARIZATIONS IN AGE-RELATED MACULAR DEGENERATION

BACKGROUND

Around 30% of nonexudative macular neovascularizations exudate within 2 years from diagnosis in patients with age-related macular degeneration. The aim of this study is to develop a deep learning classifier based on optical coherence tomography (OCT) and OCT angiography (OCTA) to identify nonexudative macular neovascularizations at risk of exudation.

METHODS

Patients with age-related macular degeneration showing OCTA and fluorescein angiography-documented nonexudative macular neovascularization with a 2-year minimum imaging follow-up were retrospectively selected. Patients showing OCT B-scan-documented macular neovascularization exudation within the first 2 years formed the EX GROUP while the others formed the QU GROUP. ResNet-101, Inception-ResNet-v2, and DenseNet-201 were independently trained on OCTA and OCT B-scan images. Combinations of the six models were evaluated with major and soft voting techniques.

RESULTS

Eighty-nine eyes of 89 patients with a follow-up of 5.7 ± 1.5 years were recruited (35 EX GROUP and 54 QU GROUP). Inception-ResNet-v2 was the best performing among the three single convolutional neural networks. The major voting model resulting from the association of the three different convolutional neural networks resulted in an improvement of performance both for OCTA and OCT B-scan (both significantly higher than human graders' performance). The soft voting model resulting from the combination of OCTA and OCT B-scan-based major voting models showed a testing accuracy of 94.4%. Peripheral arcades and large vessels on OCTA en face imaging were more prevalent in the QU GROUP.

CONCLUSION

Artificial intelligence shows high performances in identifications of nonexudative macular neovascularizations at risk for exudation within the first 2 years of follow-up, allowing better customization of follow-up timing and avoiding treatment delay. Better results are obtained with the combination of OCTA and OCT B-scan image analysis.

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.

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.

Comparative quantitative analysis of optical coherence tomography angiography in varied morphologies of macular neovascularization following intravitreal conbercept and ranibizumab treatments for neovascular age‑related macular degeneration

The present study aimed to examine the optical coherence tomography angiography (OCTA) parameters associated with macular neovascularization (MNV) in patients diagnosed with neovascular age-related macular degeneration (nAMD) and treated with either intravitreal conbercept (IVC) or ranibizumab (IVR). It enrolled 39 nAMD patients presenting with MNV, including 23 in the IVC group and 16 in the IVR group. All participants were treatment-naïve with intravitreal therapy and they underwent treatment following a '3+PRN' regimen. The MNV patterns identified through OCTA were categorized as Medusa, tangled, seafan and other variations. Key outcome measures encompassed best-corrected visual acuity (BCVA), MNV vascular area (MNV-VA), MNV vascular density (MNV-VD) ratio and central macular thickness (CMT). In the present study, 44 eyes were included, with 28 eyes undergoing treatment with IVC and 18 eyes with IVR. On day 90, there was a statistically significant improvement in mean BCVA from baseline among all patients treated with IVC (P=0.002). Notably, improved outcomes were observed in those with the 'tangled' pattern compared with the other three patterns (P=0.007). CMT exhibited a significant decrease from baseline (P=0.007), with consistent improvement observed across all four patterns (P=0.052) on day 90. The mean MNV-VA decreased in all patients, reaching statistical significance for the Medusa pattern (P=0.008), although the improvement in visual acuity was deemed unsatisfactory. Patients with the seafan pattern treated with IVR improved significantly in BCVA (P=0.042). The mean CMT significantly improved from baseline (P=0.001), consistent across the four patterns (P=0.114). Significant improvements were noted in the mean MNV-VA for the seafan pattern and in the mean MNV-VD ratio for the other patterns. The two regimens had no significant differences regarding BCVA, CMT, and MNV parameters. Conbercept emerged as a viable treatment option for patients presenting with tangled MNV patterns. On the other hand, ranibizumab might be considered an effective intervention for individuals with seafan MNV patterns. Notably, the Medusa MNV pattern was associated with a morphologic configuration indicative of a poor prognosis.

Myopic choroidal neovascularization with neovascular signal around perforating scleral vessel prone to recur after anti-VEGF therapy

BACKGROUND

To compare the recurrence of myopic choroidal neovascularization (mCNV) based on the neovascular signal of mCNV around the perforating scleral vessel (PSV).

METHODS

A consecutive series of naïve patients with mCNV accepted anti-VEGF therapy with a minimum 12-month follow-up period. The neovascular signal relationship between PSV and mCNV were classified into the presence of neovascular signal of CNV around PSV or not. The recurrence of mCNV, best-corrected visual acuity (BCVA), hyperreflective foci height, CNV area and CNV flow area were analyzed between two groups.

RESULTS

Neovascular signal of CNV around PSV was detected in 20 eyes (39.2%). The one-year recurrence rate in the group with neovascular signal of CNV around PSV was significantly higher than that in the group without neovascular signal of CNV around PSV (P = 0.045). The recurrence time in the group with neovascular signal around PSV was shorter than that in the group without neovascular signal around PSV (P = 0.030). Cox proportional hazard model showed that the presence of neovascular signal of CNV around PSV [hazard ratio (HR): 2.904] and subfoveal choroidal thickness ≤ 50 μm (HR: 0.368) were risk factors for recurrence of mCNV. In the group with neovascular signal around PSV, the BCVA was worse (P = 0.024) and the CNV flow area was more unstable (P = 0.027) after therapy.

CONCLUSIONS

PSV was commonly detected in patients with mCNV. The presence of neovascular signal of CNV around PSV was prone to recur with a shorter time in mCNV patients.

Characterizing Macular Neovascularization in Myopic Macular Degeneration and Age-Related Macular Degeneration Using Swept Source OCTA

Purpose

Visual prognosis and treatment burden for macular neovascularization (MNV) can differ between myopic macular degeneration (MMD) and age-related macular degeneration (AMD). We describe and compare MNV associated with MMD and AMD using swept-source (SS)-OCTA.

Patients and Methods

Adult patients with documented MNV associated with MMD or AMD were consecutively recruited. Qualitative and quantitative features were assessed from 6x6mm angiograms, including the MNV area and vessel density (VD). Descriptive statistics and linear regression analyses were carried out.

Results

Out of 75 enrolled eyes with diagnosed MNV (30 MMD-MNV and 45 AMD-MNV; mean age 55±19 and 75±8 years, respectively), 44 eyes had discernible MNV (11 MMD-MNV and 33 AMD-MNV) on SS-OCTA at the time of the study and were included in the analysis. The MMD-MNV group exhibited a three-fold smaller sized MNV (p=0.001), lower greatest linear dimension (p=0.009) and greatest vascular caliber (p<0.001) compared to AMD-MNVs, and had a higher prevalence of tree-in-bud pattern. Eyes with AMD showed a higher prevalence of type 1 MNVs with medusa pattern. There was no difference in the location of the MNV, shape's regularity, margins, presence of core vessel, capillary fringe, peripheral loops, or perilesional dark halo (p>0.05) between both conditions. After adjustment, decreased MNV area and increased VD were associated with the tree-in-bud pattern, whereas the diagnosis did not significantly influence those parameters.

Conclusion

While larger studies are warranted, this study is the first to describe and compare MMD-MNV and AMD-MNV using SS-OCTA, providing relevant clinical insight on MNV secondary to MMD and AMD. These findings also further validate OCTA as a powerful tool to detect and characterize MNV non-invasively.

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.

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.

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).

Clinical Use of Optical Coherence Tomography Angiography in Retinal Diseases

The advent of optical coherence tomography angiography (OCTA) is one of the cornerstones of fundus imaging. Essentially, its mechanism depends on the visualization of blood vessels by using the flow of erythrocytes as an intrinsic contrast agent. Although it has only recently come into clinical use, OCTA has become a non-invasive diagnostic tool for the diagnosis and follow-up of many retinal diseases, and the integration of OCTA in multimodal imaging has provided a better understanding of many retinal disorders. Here, we provide a detailed overview of the current applications of OCTA technology in the diagnosis and follow-up of various retinal disorders.

Biomarkers of macular neovascularisation activity using optical coherence tomography angiography in treated stable neovascular age related macular degeneration

BACKGROUND

The aim of this study was to describe features of disease activity in patients with treated stable macular neovascularisation (MNV) in neovascular age related macular degeneration (nAMD) using optical coherence tomography angiography (OCTA).

METHODS

Thirty-two eyes of 32 patients with nAMD were included in this prospective, observational study. These patients were undergoing treatment with aflibercept on a treat-and-extend regimen attending an extension to a 12-week treatment interval.

RESULTS

All subjects had no macular haemorrhage and no structural OCT markers of active MNV activity at the index 12-week treatment extension visit. 31/32 OCTA images were gradeable without significant imaging artefact. The mean MNV size was 3.6mm² ± 4.6mm² and 27 (87.1%) had detectable MNV blood flow. 29/31 (93.5%) subjects had MNV with mature phenotypes including 10 non-specific, 10 tangle and 3 deadtree phenotypes. MNV halo and MNV central feeder vessel were noted in 18 (58.1%) and 19 (61.3%) of subjects respectively; only 1 (3.2%) subject was noted to have a MNV capillary fringe.

CONCLUSIONS

MNV blood flow is still detectable using OCTA in the majority of subjects in this study with treated stable MNV. OCTA features associated included MNV mature phenotype, MNV feeder vessel, MNV halo and absence of capillary fringe.

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.

Perforating scleral vessels adjacent to myopic choroidal neovascularization achieved a poor outcome after intravitreal anti-VEGF therapy

Background

This study aimed to summarize the features of perforating scleral vessels (PSVs) in patients with myopic choroidal neovascularization (CNV) (mCNV) using optical coherence tomography angiography (OCTA) and to identify the associations with the response after intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy.

Methods

A consecutive series of naïve patients who had mCNV and received intravitreal anti-VEGF therapy with a follow-up duration of 12 months or more were enrolled. The prevalence, location, and branches of PSVs were analyzed. Projection-resolved OCTA (PR-OCTA) was used to analyze the neovascular signals between CNV and PSVs. Best corrected visual acuity (BCVA) and central macular thickness (CMT) were measured. The proportion of CMT change relative to baseline was used to assess therapeutic response.

Results

A total of 44 eyes from 42 patients with mCNV were enrolled. PSVs were identified in 41 out of 44 eyes. Branches were identified in the PSVs of 24 eyes (57.14%), and 20 eyes did not have PSV branches (47.62%). In eight eyes (18.18%), PSVs were adjacent to mCNV, and in 36 eyes (81.82%), PSVs were not adjacent to mCNV. After anti-VEGF therapy for mCNV, BCVA increased (F = 6.119, p < 0.001) and CMT decreased (F = 7.664, p < 0.001). In the eyes where PSVs were adjacent to mCNV, BCVA improvements (F = 7.649, p = 0.009) were poor, and changes in CMT were small.

Conclusion

The eyes with PSVs adjacent to mCNV showed poor therapeutic responses after intravitreal anti-VEGF therapy.

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.

Undetectable Macular Neovascularization on OCT Angiography in Age Related Macular Degeneration: Comparison between Different Devices

Background and Objectives: The aim of this study was to report the characteristics of macular neovascularization (MNV) with undetectable flow on optical coherence tomography angiography (OCTA) in neovascular age related macular degeneration (nAMD), and compare them with the characteristics of detectable MNV. Materials and Methods: Patients with a diagnosis of nAMD who underwent dye imaging and OCTA in the same day were included and divided into two groups: undetectable and detectable flow on OCTA. Three OCTA devices were used, two with spectral-domain technology (AngioVue, RTVue 100xAvanti, Optovue, Freemont, CA, USA and Heidelberg OCT2 Beta Angiography Module, Heidelberg Engineering, Germany) and one swept-source OCTA (PlexElite 9000; Carl Zeiss Meditec, Inc., Dublin, CA, USA). We studied the demographics, neovascularization characteristics, and OCTA device and acquisition characteristics for both groups. Results: A global comparison between Group 1 and Group 2 was made, followed by an analysis of variables associated with (un)detectability for each OCTA device. A total of 108 eyes were included: 90 in the detectable group (Group 1) and 18 in the undetectable group (Group 2), corresponding to a global sensitivity of OCTA for the detection of MNV of 83.49%. There was a statistically significant difference between the two groups regarding MNV type (p = 0.02) and PED height (p = 0.017). For the three devices, detection sensitivity with automatic segmentation was significantly lower than with manual segmentation. For Heidelberg, PED Height and scan quality explained 68.3% of the undetectability. For AngioVue, PED Height and absence of hemorrhage explained 67.9% of undetectability. Conclusions: In this study, we found a global sensitivity of 83.49% for the three OCTA devices combined, with a range from 55.5% to 96.26% depending on the segmentation and OCTA device. This means that undetectable/undetected MNV can represent up to 45% of the examinations, eventually misdiagnosing choroidal neovascularization for 1 out every 2 patients.

Quantitative analysis of branching neovascular networks in polypoidal choroidal vasculopathy by optical coherence tomography angiography after photodynamic therapy and anti-vascular endothelial growth factor combination therapy

PURPOSE

To study serial changes in branching neovascular networks (BNN) by using optical coherence tomography angiography (OCTA) in patients with polypoidal choroidal vasculopathy (PCV) who underwent combined photodynamic therapy (PDT) and anti-vascular endothelial growth factor (anti-VEGF) therapy.

METHODS

In this retrospective study of 30 PCV patients who underwent combined therapy, OCTA images obtained at baseline and 1, 3, and 6 months after treatment were collected. The vessel area, vessel percentage area, average vessel length, and presence of polypoidal lesions on OCTA images as well as best-corrected visual acuity (BCVA), central retinal thickness (CRT), and central choroidal thickness (CCT) were recorded at each time point.

RESULTS

The BNN- and polypoidal lesion-detection rates on baseline OCTA images were 100% and 71%, respectively. The vessel area decreased during the first 3 months, and increased 6 months post-treatment, showing significant differences from baseline (p = 0.031). The vessel percentage area also reduced 1 and 3 months post-treatment (p = 0.025) and increased 6 months post-treatment. Continuous polypoidal lesion regression was observed from 1 to 3 and 6 months post-treatment (p = 0.031, p = 0.004, p = 0.002, respectively, in comparison with baseline). Patients with a decreasing vessel area over 6 months showed greater choroidal thickness than those with increasing vessel area (p = 0.004).

CONCLUSIONS

The BNN showed initial regression but were enlarged at 6 months after therapy. Patients showing continuous BNN regression showed a thicker choroid at baseline. This difference should be considered during treatment for PCV, and OCTA could be used for follow-up evaluations of PCV patients.

Quantitative OCT angiography findings according to pattern classification of type 1 neovascularization exudative age-related macular degeneration

OBJECTIVES

To define neovascularization (NV) patterns and their association with exudative activity in type 1 neovascular age-related macular degeneration (NVAMD).

METHODS

In optical coherence tomography angiography (OCTA) images of type 1 NVAMD, we stratified NV patterns according to whether they contained core vessel (C+/C-) and fine branching vessels (F+/F-) or not into C - F +, C + F +, and C + F - groups. Qualitative analyses assessing the status of peripheral tiny branching, inner branching capillaries, arcade, loop, and perilesional halo and quantitative analyses considering the NV area, length, density, and numbers of junctions and endpoints (open-ended vessels) in NV were conducted according to NV patterns and the presence of exudation on structural OCT.

RESULTS

Among 96 eyes, exudation was found in the C - F + (33.3%) and C + F + (47.6%) groups, related to peripheral tiny branching in both groups (p = 0.022 and p < 0.001) and perilesional halo in the C + F + group (p < 0.001). Peripheral arcades, inner branching capillaries, and loops were observed in more than half (68.3%, 58.7%, and 69.8%) in the C + F + group but not related with exudative activity in the C + F + group. In quantitative analysis, the number of endpoints was associated with exudation in univariate and multivariate analyses (p = 0.011 and p = 0.016) in C + F + group.

CONCLUSIONS

After pattern classification, type 1 NV patterns with fine branching vessels were considered to have exudative activity compared to NV without fine branching. The quantitative analysis of type 1 NV according to patterns showed the presence of peripheral tiny branching vessels was associated with NV activity.

Baseline predictors for subretinal fibrosis in neovascular age-related macular degeneration

To find baseline predictors for subretinal fibrosis (SF) in neovascular age-related macular degeneration (nAMD). Forty-five eyes of 45 participants with treatment-naïve nAMD were consecutively enrolled and treated according to a standardized treat-and-extend protocol. Spectral-domain optical coherence tomography (OCT), color fundus photography and fluorescein angiography as well as novel imaging modalities polarization-sensitive OCT and OCT angiography (OCTA) were performed to detect SF after 1 year and find baseline predictors for SF development. Baseline OCTA scans were evaluated for quantitative features such as lesion area, vessel area, vessel junctions, vessel length, vessel endpoints and mean lacunarity. Additionally, the type of macular neovascularization, the presence of subretinal fluid, intraretinal fluid (IRF), subretinal hyperreflective material (SHRM), retinal hemorrhage as well as best-corrected visual acuity (BCVA) were evaluated. After 12 months 8 eyes (18%) developed SF. Eyes with SF had worse baseline BCVA (p = .001) and a higher prevalence of IRF (p = .014) and SHRM at baseline (p = .017). There was no significant difference in any of the evaluated quantitative OCTA parameters (p > .05) between eyes with and without SF. There were no quantitative baseline microvascular predictors for SF in our study. Low baseline BCVA, the presence of IRF and SHRM, however, are easily identifiable baseline parameters indicating increased risk.

Five-Year Reactivation After Ranibizumab or Aflibercept Treatment for Neovascular Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy

Purpose: To evaluate 5-year reactivation after ranibizumab or aflibercept treatment for neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV). Methods: This retrospective study included 192 patients (192 eyes) who had been diagnosed with neovascular AMD or PCV and treated with ranibizumab or aflibercept. The incidence and timing of lesion reactivation during the 5-year follow-up period were evaluated, and the factors associated with reactivation were also investigated. Results: During the follow-up period, lesion reactivation was noted in 156 patients (81.3%) at a mean of 9.5 ± 10.5 months after the third antivascular endothelial growth factor injection. The incidence of reactivation was 59.9% during the first 12 months, 33.7% during ≥12 and <24 months, 11.8% during >24 and ≤36 months, 15.5% during >36 and ≤48 months, and 5.3% during >48 and ≤60 months. There was a significant difference in the incidence among the 5 periods (P < 0.001). The proportion of PCV was significantly higher in patients experiencing reactivation (51.9%) than in those who did not (30.6%) (P = 0.021). Conclusions: During the 5-year follow-up, lesion reactivation was noted in approximately four-fifths of the patients. The incidence of lesion reactivation was highest during the first 12 months and decreased thereafter. The incidence was higher in patients with PCV than in those with neovascular AMD, especially after 12 months.

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.

Combined quantitative and qualitative optical coherence tomography angiography biomarkers for predicting active neovascular age-related macular degeneration

To investigate choroidal neovascularization (CNV) characteristics after anti-vascular endothelial growth factor (anti-VEGF) therapy in patients with neovascular age-related macular degeneration by optical coherence tomography angiography (OCTA) and to assess the potential predictive role of combined qualitative and quantitative biomarkers for disease activity. Patients diagnosed with type 1 or type 2 CNV via multimodal imaging who had received anti-VEGF treatment were retrospectively reviewed. Qualitative and quantitative CNV responses on OCTA after serial injections were analyzed. The enrolled eyes were divided into two groups based on treatment intervals during follow-up, including an active group with less than 12 weeks intervals and a stable group with 12 weeks or longer intervals. Fifty-six eyes of 56 patients were included in the study. Twenty-seven eyes (48.2%) were classified as the “active group”, and 29 eyes (51.8%) were categorized as the “silent group”. Qualitative biomarkers of CNV showed significant differences between the two groups (branching capillaries: 48.1% vs 6.9%, p = 0.001; anastomoses and loops: 81.5% vs 13.8%, p < 0.001; peripheral arcade: 40.7% vs 10.3%, p = 0.013, and hypointense halo: 81.5% vs 41.4%, p = 0.002). A significantly higher vessel density was found in the active group (median 39.6% vs 30.5%, p = 0.003). “Anastomoses and loops” and “vessel density” predicted an active CNV status with a probability of 93.7% and achieved the best performance. The combination of two potential biomarkers of CNV on OCTA shows good discrimination for the prediction of recurrent exudation auxiliary to structural OCT that might associate with disease activity.

PREDICTIVE ACTIVATION BIOMARKERS OF TREATMENT-NAIVE ASYMPTOMATIC CHOROIDAL NEOVASCULARIZATION IN AGE-RELATED MACULAR DEGENERATION

PURPOSE

To assess the long-term evolution of treatment-naive quiescent choroidal neovascularization (CNV), in age-related macular degeneration (AMD), to identify predictive activation biomarkers.

METHODS

Patients with quiescent CNV underwent a comprehensive ophthalmological examination, including fluorescein and indocyanine green angiographies, structural optical coherence tomography (OCT), and OCT angiography. Qualitative and quantitative analyses of structural OCT and OCT angiography images were performed during the study period. At the last follow-up evaluation, the enrolled eyes were divided into two groups: eyes with quiescent CNV converting to exudative AMD (eAMD) and those not progressing to eAMD.

RESULTS

Sixty-eight eyes of 68 patients were enrolled in the study. Mean follow-up duration was 40 ± 28 months using multimodal imaging and 22 ± 13 months using OCT angiography. On structural OCT, quiescent CNV not converting to eAMD showed a preferential growth of the pigment epithelium detachment greatest linear diameter (P = 0.009), whereas the eAMD group presented a preferential growth of the pigment epithelium detachment maximal height (P < 0.0001) during the study period. Quantitative analysis of choriocapillaris OCT angiograms confirmed the CNV area growth during follow-up (from 4.18 ± 4.77 mm at baseline to 5.10 ± 5.06 mm at the last follow-up visit; P = 0.02).

CONCLUSION

A close follow-up is recommended to early identify predictive activation biomarkers of treatment-naive quiescent CNV.

Imaging Biomarkers of 1-Year Activity in Type 1 Macular Neovascularization

Purpose

The purpose of this study was to evaluate the predictive value of optical coherence tomography (OCT) and OCT angiography (OCTA) parameters at baseline on lesion's activity at the 1-year follow-up in type 1 macular neovascularizations (MNVs) treated with 1-year fixed regimen of intravitreal aflibercept injections (q8 IAIs).

Methods

All patients were imaged by structural OCT to evaluate central macular thickness (CMT), subretinal fluid (SRF), subretinal hyper-reflective material (SHRM), intraretinal fluid (IRF) and intraretinal hyper-reflective dots (HRDs), and by Swept-Source OCTA to measure baseline MNV area, perfusion density (PD), vessel length density (VLD), and vessel diameter index. At the end of q8 IAI, patients were classified in two groups: active-MNV (A-MNV) and inactive-MNV (I-MNV), considering the OCT signs of activity. Three binary logistic regression models were developed: (1) OCT-based, (2) OCTA-based, and (3) OCT/OCTA-based model.

Results

Thirty-one treatment-naïve type 1 MNVs were enrolled (13 A-MNV and 18 I-MNV). No differences were observed in baseline OCT and OCTA characteristics between A-MNV and I-MNV. Among the models developed, model 3 that combined OCT/OCTA parameters showed a performance of 87.5% and excellent sensitivity for A-MNV lesions (100%). By analyzing the model, the A-MNV group appears more likely to show at baseline SRF, greater CMT, wider MNV area, and lower PD and VLD compared to I-MNV.

Conclusions

Our study demonstrated that the combination of baseline OCT and OCTA parameters allowed to achieve a good models’ performance in the prediction of MNV activity permitting to correctly classifying the active lesions at the end of follow-up period, with excellent sensitivity.

Translational Relevance

OCT/OCTA could integrate statistical models potentially useful for artificial intelligence.

AI-based monitoring of retinal fluid in disease activity and under therapy

Retinal fluid as the major biomarker in exudative macular disease is accurately visualized by high-resolution three-dimensional optical coherence tomography (OCT), which is used world-wide as a diagnostic gold standard largely replacing clinical examination. Artificial intelligence (AI) with its capability to objectively identify, localize and quantify fluid introduces fully automated tools into OCT imaging for personalized disease management. Deep learning performance has already proven superior to human experts, including physicians and certified readers, in terms of accuracy and speed. Reproducible measurement of retinal fluid relies on precise AI-based segmentation methods that assign a label to each OCT voxel denoting its fluid type such as intraretinal fluid (IRF) and subretinal fluid (SRF) or pigment epithelial detachment (PED) and its location within the central 1-, 3- and 6-mm macular area. Such reliable analysis is most relevant to reflect differences in pathophysiological mechanisms and impacts on retinal function, and the dynamics of fluid resolution during therapy with different regimens and substances. Yet, an in-depth understanding of the mode of action of supervised and unsupervised learning, the functionality of a convolutional neural net (CNN) and various network architectures is needed. Greater insight regarding adequate methods for performance, validation assessment, and device- and scanning-pattern-dependent variations is necessary to empower ophthalmologists to become qualified AI users. Fluid/function correlation can lead to a better definition of valid fluid variables relevant for optimal outcomes on an individual and a population level. AI-based fluid analysis opens the way for precision medicine in real-world practice of the leading retinal diseases of modern times.

Replacement of polyps with type 1 macular neovascularization in polypoidal choroidal vasculopathy imaged with swept source OCT angiography

Purpose

To investigate the morphological changes of polyps in eyes with polypoidal choroidal vasculopathy (PCV) after treatment with vascular endothelial growth factor (VEGF) inhibitors using swept source optical coherence tomography angiography (SS-OCTA).

Observations

Following anti-VEGF therapy, polyps were found to evolve into typical type 1 macular neovascularization (MNV) in five eyes. In all of these five eyes, a polypoidal lesion was detected adjacent to a serous or hemorrhagic retinal pigment epithelial detachment (PED).

Conclusions and importance

Polypoidal lesions in PCV can evolve into typical type 1 MNV. This morphological evolution suggests that these polyps are clusters of tangled vessels that can proliferate into a more typical neovascular pattern, and this evolution may be facilitated by being adjacent to a PED. Since this morphological appearance could be associated with a better prognosis, SS-OCTA might be helpful in identifying cases of transformed polyps that may be associated with a decreased risk for vision loss.

Quantitative Analysis of the Activity in Choroidal Neovascularizations after a Single Anti-VEGF Injection: OCT Versus OCT Angiography

PURPOSE

To analyze early quantitative changes in the choroidal neovascularization (CNV) area observed with optical coherence tomography angiography (OCTA) after single anti-vascular endothelial growth factor (anti-VEGF) injection.

MATERIALS AND METHODS

Treatment-naive patients with CNV secondary to neovascular age-related macular degeneration were analyzed immediately before and ~4 weeks after anti-VEGF injection. The primary endpoints of the study included changes in CNV total and vascular area. Secondary endpoints were best-corrected visual acuity (BCVA), central macular thickness (cMT), central total macular thickness (cTMT), and subfoveal choroidal thickness (SFCT).

RESULTS

A total of 27 patients (69.19 ± 5.91 years, 21 men/6 women, 14 type 1 NV, 11 type 2 NV, and 2 type 3 NV) were included in the study. There was a significant increase in BCVA and decreases in cMT, cTMT, and SFCT after treatment (p<0.05 for all). CNV total and vascular area changed by -11.55 ± 44.26% (95% confidence interval [CI]: -29.06 and 5.95; p=0.269) and -21.06 ± 41.2% (95% CI: -36.45/-5.67; p=0.786), respectively. The cases with decreased cTMT were accompanied by a decrease in CNV area only in 37% of the cases. No significant correlation was detected between cTMT and CNV total and vascular area percentage changes (r = -0.06, p=0.74; r = 0.02, p=0.9, respectively).

CONCLUSIONS

Changes in CNV total and vascular area seem to have limited sensitivity as a biomarker in terms of activation, as wide variability was observed in CNV area after anti-VEGF injection.

Flow pattern and perforating vessels in three different phases of myopic choroidal neovascularization seen by swept-source optical coherence tomography angiography

PURPOSE

To compare the choroidal neovascularization (CNV) flow patterns and the relationship between perforating vessels (PVs) and CNV in the three different stages of networks in myopic CNV (mCNV) using swept-source optical coherence tomography angiography (SS-OCTA).

METHODS

This retrospective study included 28 eyes with mCNV that was divided into three phases (active, scar, and atrophic) and observed by SS-OCTA. SS-OCTA findings, with special focus on the relationship between the PVs and CNV, were compared among the three phases.

RESULTS

Overall, the CNV signal was detected in 31 of the 34 areas of CNV (91%); in the active, scar, and atrophic phases, respectively, CNV signals were detected in eight of eight areas of CNV (100%), 10 of 11 areas of CNV (91%), and 13 of 15 areas of CNV (86%). Two signal patterns were observed in each phase, i.e., dense and loop; in the atrophic phase, seven eyes were unclassifiable. The ratio between the dense and loop patterns did not differ significantly among the phases. In 30 of 34 areas of CNV for which clear images were obtained, the PVs and CNV were connected directly or indirectly in 19 area of CNV, and in five areas of CNV, trunk-like vessels were connected to the PVs within the CNV. The numbers of foveal or parafoveal CNVs accompanied by PVs were significantly (p=0.0048) greater than those of the extrafoveal CNV.

CONCLUSIONS

OCTA provides detailed observation of mCNV and the relationship between CNV and PVs. Although the CNV signal pattern does not differ depending on the degree of atrophy, there are cases in which only the trunk-like vessels connect to the PVs within the CNV in the atrophic phase without CNV flow signal.

Optical Coherence Tomography Angiography of the Choriocapillaris in Age-Related Macular Degeneration

The advent of optical coherence tomography angiography (OCTA) has allowed for remarkable advancements in our understanding of the role of the choriocapillaris in age-related macular degeneration (AMD). As a relatively new imaging modality, techniques to analyze and quantify choriocapillaris images are still evolving. Quantification of the choriocapillaris requires careful consideration of many factors, including the type of OCTA device, segmentation of the choriocapillaris slab, image processing techniques, and thresholding method. OCTA imaging shows that the choriocapillaris is impaired in intermediate non-neovascular AMD, and the severity of impairment may predict the advancement of disease. In advanced atrophic AMD, the choriocapillaris is severely impaired underneath the area of geographic atrophy, and the level of impairment surrounding the lesion predicts the rate of atrophy enlargement. Macular neovascularization can be readily identified and classified using OCTA, but it is still unclear if neovascularization features with OCTA can predict the lesion’s level of activity. The choriocapillaris surrounding macular neovascularization is impaired while the more peripheral choriocapillaris is spared, implying that choriocapillaris disruption may drive neovascularization growth. With continued innovation in OCTA image acquisition and analysis methods, advancement in clinical applications and pathophysiologic discoveries in AMD are set to follow.

IMPLICATIONS OF THE MORPHOLOGIC PATTERNS OF TYPE 1 MACULAR NEOVASCULARIZATION ON MACULAR ATROPHY GROWTH ON PATIENTS UNDER ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR TREATMENT

PURPOSE

To evaluate the correspondence between macular atrophy (MA) progression and Type 1 macular neovascularization morphology during long-term anti-vascular endothelial growth factor treatment for exudative neovascular age-related macular degeneration.

METHODS

Retrospective review of consecutive patients with complete retinal pigment epithelium and outer retina atrophy overlying or in the proximity of macular neovascularization. The assessment of MA was based on spectral domain optical coherence tomography, en-face near infra-red imaging and fundus autofluorescence. Macular neovascularization blood flow morphology was evaluated by swept-source optical coherence tomography-angiography. Qualitative features were categorized per ETDRS sector as: immature, mature; and hypermature pattern. An automatic analysis was designed in MATLAB coding language to compute MA per ETDRS. Measurements were compared between the baseline and the last follow-up visit.

RESULTS

Twenty eyes from 20 patients were included; the mean age was 85.4 (8.3) years. The median follow-up was 1.85 (1.0-2.4) years and the median anti-vascular endothelial growth factor injection rate during follow-up was 4.0 (2.0-5.0) injections/year. During follow-up, sectors with persistence of an immature blood flow pattern had a lower MA growth rate than sectors with mature macular neovascularization flow patterns (P = 0.001).

CONCLUSION

The presence of an immature blood flow pattern on optical coherence tomography-angiography is associated with a lower progression rate of MA.

QUANTITATIVE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FEATURES OF INACTIVE MACULAR NEOVASCULARIZATION IN AGE-RELATED MACULAR DEGENERATION

PURPOSE

To compare quantitative optical coherence tomography angiography parameters between treatment-naïve quiescent macular neovascularizations (MNVs) and previously treated nonexudative Type 1 MNVs, in patients with age-related macular degeneration.

METHODS

The eyes included in the study were analyzed by fluorescein angiography, indocyanine green angiography, spectral-domain optical coherence tomography, and optical coherence tomography angiography. According to their medical history and multimodal imaging evaluation, Type 1 MNVs were divided into 2 groups: 1) treatment-naïve quiescent MNVs; 2) previously treated nonexudative Type 1 MNVs. Quantitative optical coherence tomography angiography parameters, including perfusion density (PD), fractal dimension (FD), and lacunarity (LAC) were calculated. Receiver operating characteristic curves, showing the ability of PD, FD, and LAC to discriminate between the two MNV groups, were built.

RESULTS

Twenty-two eyes with treatment-naïve quiescent MNVs and 20 eyes with MNVs previously treated nonexudative Type 1 MNVs were analyzed. Mean FD and LAC were statistically different between the two study groups (P < 0.05). Lacunarity showed the best discrimination ability, followed by FD and PD (area under curve = 0.83, 0.78, 0.62, respectively).

CONCLUSION

Results suggest that FD and LAC may be useful optical coherence tomography angiography biomarkers to objectively discriminate inactive MNVs with different prognosis, such as treatment-naïve quiescent MNVs and previously treated nonexudative Type 1 MNVs, in age-related macular degeneration patients.

[Fibrovascular transformation of CNV in nAMD after long-term anti-VEGF therapy : Methodological evaluation of quantifying morphological changes]

BACKGROUND

Under long-term anti-VEGF therapy neovascular age-related macular degeneration (nAMD) may result in fibrovascular transformation of choroidal neovascularization (CNV). So far there is a lack of definitions on how a differentiated quantification of the associated morphological changes can best be carried out. This pilot study aimed to define the most appropriate imaging modalities.

PATIENTS AND METHODS

In 56 eyes with fibrotic CNV after at least 2 years of anti-VEGF therapy and at least 12 intravitreal anti-VEGF injections, the following imaging modalities were investigated with respect to the delimitation of vascular and fibrous portions of CNV as well as associated atrophy of retinal pigment epithelium (RPE) and disruption of the ellipsoid zone (EZ): multicolor imaging (MC), fundus autofluorescence (FAF), fluorescein angiography (FA) and indocyanine green angiography (ICGA), spectral domain optical coherence tomography (SD-OCT) and OCT angiography (OCTA).

RESULTS

The vascular portion of fibrotic CNV was best visualized by OCTA, the fibrous portion by SD-OCT. The RPE atrophy was best delimitated by FAF, but differentiation was also possible by MC and ICGA. Disruption of the EZ could be delineated by SD-OCT b‑scan.

CONCLUSION

The use of MC is suitable for visualization of RPE atrophy and the fibrous portion of fibrotic CNV and FAF is suitable for differentiation of RPE atrophy. The SD-OCT can be used to quantify the fibrous portion of CNV; the EZ interruption is delimitable in the b‑scan but not in the transverse structure-scan. The vascular part can best be detected by OCTA.

Assessment of conbercept therapy for high myopia macular neovascularization by optical coherence tomography angiography

This study aimed to evaluate the efficacy and safety of the intravitreal injection of conbercept in the treatment of macular neovascularization (MNV) secondary to high myopia and to observe the application of optical coherence tomography angiography (OCTA) in the treatment follow-up. We reviewed the medical records of 20 patients (21 eyes) with MNV secondary to high myopia who were enrolled in the Department of Ophthalmology of the First Hospital of China Medical University between May 2018 and January 2020. Each patient received one or more intravitreal injections of conbercept (0.5 mg/0.05 mL). The treatment was conducted according to a 1 + PRN (pro re nata) regimen. The changes of best corrected visual acuity (BCVA), central macular thickness (CMT), and selected MNV and flow areas measured by OCTA were observed over a 6-month follow-up period. The mean logarithm of the minimum angle of resolution (logMAR) BCVA was 1.03 ± 0.61 before treatment and improved to 0.83 ± 0.59 (P = 0.007), 0.78 ± 0.62 (P = 0.001), 0.81 ± 0.73 (P = 0.027), and 0.79 ± 0.72 (P = 0.023) at 1 month, 2 months, 3 months, and 6 months after treatment, respectively. The mean CMT was 358.16 ± 206.11 μm before treatment and decreased to 295.38 ± 178.70 μm (P = 0.003), 288.34 ± 165.60 μm (P = 0.004), 284.36 ± 163.07 μm (P = 0.005), and 283.00 ± 160.32 μm (P = 0.004) at 1 month, 2 months, 3 months, and 6 months after treatment, respectively. Nineteen eyes (90.5%) had stable or improved vision at 6 months of follow-up. One month after conbercept injection, in OCTA images, the small-diameter blood vessels of the MNV decreased, the intertwined small blood vessels decreased or even disappeared, and the main or larger-diameter blood vessels were still present. The mean selected MNV and blood flow areas were 0.62 ± 0.81 and 0.22 ± 0.27 mm², respectively, before treatment and decreased to 0.23 ± 0.33 and 0.07 ± 0.08 mm² (P = 0.04 for both), respectively, 1 month after treatment. No drug-related systemic or ocular adverse effects were observed. Our results suggest that conbercept can effectively and safely improve BCVA and reduce CMT in patients with myopic MVN (mMNV). OCTA can be used to observe MNV area, blood flow area, and MNV morphological changes after treatment with conbercept, thus providing a reference for treatment follow-up.

Analysis of the Vascular Morphology of the Fibrotic Choroidal Neovascularization in Neovascular Age-Related Macular Degeneration Using Optical Coherence Tomography Angiography

Purpose Choroidal neovascularization (CNV) in neovascular age-related macular degeneration (nAMD) undergoing anti-VEGF therapy transforms into a fibrotic lesion. This fibrovascular transformation is associated with a great variety of functional and morphological effects. The aim of this study was to investigate the vascular morphology of fibrotic CNV, to compare it with its surrounding tissue and to identify phenotypes using optical coherence tomography angiography (OCTA).

Methods In 18 eyes with fibrotic CNV in nAMD spectral domain OCT (SD-OCT) and OCTA were performed. The automated segmentation lines were manually adjusted. A slab from 60 µm beneath Bruchʼs membrane to the inner edge of the subretinal hyperreflective material was applied. Quantitative analysis of the vascular morphology was performed using skeletonized OCTA images.

Results Compared to the perilesional rim, the number of segments per area was significantly lower (234.75 ± 25.68 vs. 255.30 ± 20.34 1/mm2, p = 0.0003) within the fibrovascular lesion. Two phenotypes could be identified within the lesion. The phenotypic traits of cluster 1 were few, long and thick vascular segments; Cluster 2 was characterized by many, short and thin vascular segments (number of segments per area: 219.4 ± 18.8 vs. 258.8 ± 13.2 1/mm2, p = 0.00009, segment length: 49.6 ± 2.7 vs. 45.0 ± 1.3 µm, p = 0.0002, vascular caliber: 26.6 ± 1.2 vs. 23.5 ± 1.8 µm, p = 0.003). The clusters did not differ significantly regarding visual acuity (0.52 ± 0.44 vs. 0.54 ± 0.18 logMAR, p = 0.25), differentiability of subretinal (OR = 3.43, CI = [0.30, 39.64], p = 0.6) and intraretinal fluid (OR = 5.34, CI = [0.48, 89.85], p = 0.14). Less normalized ellipsoid zone (EZ) loss could be observed in cluster 1 (131.0 ± 161.3 vs. 892.4 ± 955.6 1/m, p = 0.006).

Conclusion In this study the vascular morphology of fibrotic CNV was analyzed using OCTA. Differences between the lesion and a perilesional rim could be detected. Two phenotypes within the fibrovascular lesion were identified. These morphological clusters could indicate different patterns of fibrovascular transformation of the CNV under long-term anti-VEGF therapy and be useful identifying possible predictive biomarkers in future studies.

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

Background

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

Methods

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

Results

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

Conclusions

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

Optical coherence tomography angiography cyclic remodeling of CNV in patients affected by Best macular dystrophy

PURPOSE

To evaluate the effect of photodynamic therapy and/or intravitreal injections on choroidal neovascularization in treatment-naïve patients affected by Best Macular Dystrophy using OCT-A.

MATERIALS AND METHODS

BMD patients with CNV treated using PDT and/or IV were included in the study. All patients underwent a complete ophthalmological examination, OCT and 3 × 3 mm OCT-A. The OCT-A images were analyzed using an open-source software (ImageJ) to assess the CNV membrane area (CNV-MA), the CNV vessel area (CNV-VA), and vessel density (VD) at the follow-ups (3 months after PDT and 1 month after IV).

RESULTS

Five eyes of four patients with CNV were included. All eyes received PDT as first-line therapy; 4 eyes underwent more than 1 treatment session: three eyes received 1 IV, whereas one eye had one further PDT. After PDT, the CNV-MA, CNV-VA, and VD quantitative parameters were obtained for four out of five eyes: in three eyes of two patients CNV-MA, CNV-VA, and VD first decreased and then gradually increased during follow-up, whereas in one eye of one patient CNV-MA, CNV-VA, and VD slightly increased. After IV the CNV-MA, CNV-VA, and VD had significantly decreased at the 1-month follow-up in three eyes of three patients.

CONCLUSION

OCT-A is an important tool for the diagnosis of both naïve and fibrotic CNV in BMD patients; it is a non-invasive method for the qualitative and quantitative analysis of neovascular lesions during follow-up. Our results have shown a cyclic remodeling of treated CNV in BMD patients using both PDT and IV.

Establishing a mouse model of choroidal neovascularization to study the therapeutic effect of levotinib and its mechanism

Objective

To study the therapeutic effect and mechanism of levotinib on choroidal neovascularization (CNV) in mice.

Methods

45 healthy C57BL/6 mice were selected and randomly divided into three groups: control group (group A), model group (group B) and levotinib group (group C). The model of CNV in mice was established. The fluorescence leakage of choroidal lesions in mice was observed by fundus fluorescein angiography. The morphological changes of retinal vessels in mice were observed by retinal slice preparation, the pathological changes of eyeball tissues in mice were observed by hematoxylin-eosin (HE) staining, the expression of vascular endothelial growth factor (VEGF) in mice retina was detected by real-time quantitative fluorescence PCR, and the protein expression of VEGF in mice retina was detected by Western blotting.

Result

On the 7th, 14th and 21st day after modeling, compared with group B, the fluorescence leakage area of group C mice was significantly reduced, and the difference was statistically significant (P < 0.05). The morphology of retinal vessels in group A was normal. In group B, the retinal vessels showed large areas of ischemia without perfusion and abundant neovascularization clusters and capillaries. Compared with group B, the morphology of retinal vessels in group C was significantly improved. Group A mice had normal eyeball structure, group B mice had visible spindle-like damage to the inner and outer retina, while group C mice had significantly less spindle-like damage than group B. Compared with group A, group B mice had significantly higher expression of retinal VEGF and the difference was statistically significant (P < 0.05), but compared with group B mice, the expression of VEGF in the retina of mice in group C was significantly decreased, and the difference was statistically significant (P < 0.05). Compared with group A, the expression of VEGF in retina of group B mice was significantly increased, and the difference was statistically significant (P < 0.05). Compared with group B, the expression of VEGF in retina of group C mice was significantly decreased, and the difference was statistically significant (P < 0.05).

Conclusion

Levatinib has obvious therapeutic effect on CNV, which may be achieved by inhibiting the high expression of VEGF in CNV.

Comparison of different morphologies of choroidal neovascularization evaluated by ocular coherence tomography angiography in age-related macular degeneration

IMPORTANCE

The clinical implications of different morphologies of choroidal neovascularization (CNV), as evaluated by ocular coherence tomography angiography (OCTA) in neovascular age-related macular degeneration (nAMD), are lacking.

BACKGROUND

To describe the morphology of CNV in nAMD using OCTA, and to compare the visual prognosis and other structural OCT biomarkers between different morphologic patterns.

DESIGN

Retrospective cohort study.

PARTICIPANTS

One hundred and forty eyes with nAMD treated with anti-vascular endothelial growth factor (VEGF).

METHODS

Patients were examined using OCTA prior to and at 3, 6 and 12 months after receiving anti-VEGF therapy.

MAIN OUTCOME MEASURES

Best-corrected visual acuity (BCVA) and morphologic retinal features.

RESULTS

Organized CNV was identified in 110/140 eyes (78.6%) using OCTA. These CNV complexes could be divided into three OCTA patterns: the 'medusa' pattern (n = 41), characterized by branching vessels radiating in all directions; the 'seafan' pattern (n = 43), characterized by branching vessels radiating to one side of the lesion; and the 'tangled' pattern (n = 26), characterized by globular entwined vessels without a main trunk. At baseline, the eyes with the tangled pattern were from younger patients (P = .031) with better BCVA (P = .007). There were also fewer intraretinal cysts (P = .021), less fibrovascular pigment epithelial detachment (P = .009), and more pachychoroid (P = .007) in eyes with the tangled pattern on OCT. At 12 months post-treatment, patients with the tangled CNV pattern also showed greater visual improvement than patients with the other two patterns (P = .049).

CONCLUSIONS AND RELEVANCE

Using OCTA, distinct morphologies of CNV in nAMD patients were identified. These different patterns might be useful predictors for the prognosis of nAMD patients after anti-VEGF therapy.

Agreement of Spectral-Domain OCT with Fluorescein Leakage in Neovascular Age-Related Macular Degeneration: Post Hoc Analysis of the HARBOR Study

PURPOSE

To evaluate the agreement between detection of activity of choroidal neovascularization (CNV) in neovascular age-related macular degeneration (AMD) by fundus fluorescein angiography (FFA) and spectral-domain (SD) OCT in the HARBOR study. Most retina specialists rely on OCT to guide treatment decisions in neovascular AMD. However, OCT may not always detect exudative activity. Traditionally, FFA was frequently performed in clinical practice, but its use has diminished due to reliance on OCT.

DESIGN

Retrospective post hoc analysis of prospective clinical trial (HARBOR; ClinicalTrials.gov identifier, NCT00891735).

PARTICIPANTS

Patients with neovascular AMD in the HARBOR Trial.

METHODS

Baseline to month 24 data from all randomized study eyes in HARBOR with both FFA and SD OCT data were analyzed for (1) evidence of CNV activity on SD OCT (presence of subretinal fluid, intraretinal fluid, and/or cystoid spaces); (2) evidence of CNV activity on FFA identified by the presence of leakage, and (3) cross-tabulation of CNV activity identified by FFA and SD OCT by office visit.

MAIN OUTCOME MEASURES

The percent agreement between FFA and SD OCT in detecting CNV activity and sensitivity and specificity of SD OCT to detect fluorescein leakage in neovascular AMD using FFA as the reference standard.

RESULTS

At baseline, 1094 patients (99.9%) had agreement between SD OCT and FFA in detecting CNV activity. By month 24, of the 779 total active cases, the agreement was only 36% (277 cases). By month 24, most cases (n = 452 [58%]) had evidence of CNV activity on SD OCT only, whereas 6% of cases (n = 50) had CNV activity identified by FFA only. At screening and months 3, 6, 12, and 24, 92% to 100% of cases identified by FFA only were occult CNV lesions. Using FFA as the reference standard, the sensitivity and specificity of SD OCT in detecting CNV activity was 91% (95% confidence interval [CI], 84%-99%) and 13% (95% CI, 4%-22%).

CONCLUSIONS

Spectral-domain OCT alone can be relied upon for detecting CNV activity while monitoring eyes with neovascular AMD. However, FFA may still be of value in those with occult lesions that appear quiescent on SD OCT, as this type of lesion may show leakage on FFA.

Optic Coherence Tomography Angiography Findings of Bilateral Choroidal Neovascularization Associated with Optic Disc Drusen Treated with Intravitreal Aflibercept Injection

Purpose

The purpose of this case report is to present the findings of optical coherence tomography angiography (OCTA) of a patient with bilateral choroidal neovascularization (CNV) associated with optic disc drusen (ODD), who was treated with intravitreal aflibercept injection. Case presentation. A 14-year-old girl presented with a complaint of visual loss and metamorphopsia in her both eyes. Best-corrected visual acuity (BCVA) was 20/32 and 20/25, respectively, in the right and left eyes. Intraocular pressure and anterior segment examination were normal. Dilated fundus examination revealed elevated optic discs with blurred margins in both eyes. In addition, slightly elevated yellow lesion extending from optic nerve head to the macula was observed bilaterally. The patient underwent imaging with colour fundus photography, fundus autofluorescence (FAF), fundus fluorescein angiography (FFA), spectral-domain optic coherence tomography (SD-OCT), OCTA, orbital ultrasonography (USG), and computed tomography (CT). In particular, OCTA demonstrated clearly the large circular CNV complex in the right eye and the CNV structure in the left eye containing slightly activated main trunk and minimal vessel loops in the papillomacular region. CNV secondary to bilateral ODD was suspected. Intravitreal aflibercept injections were performed in 3 doses to the right eye and a single dose to the left eye. After the injections, BCVA reached its complete level in both eyes. SD-OCT revealed irregularity of RPE in the temporal region of the optic disc and complete regression of the subretinal fluid. Interestingly, the entire CNV complex including the main trunk completely disappeared in OCTA. CNV complex was not observed in OCTA during 1-year follow-up, and peripapillary and macular vascular density measurements did not show any significant change. BCVA was preserved, and no additional injections were needed.

Conclusion

It is possible that OCTA can be used for detailed evaluation of CNV associated with ODD, response to anti-VEGF treatment, and peripapillary and macular vascular density. There is a need for further studies to confirm the changes such as disappearance of CNV in OCTA after injection as we observed in our patient.

Predictors of neovascular activity during neovascular age-related macular degeneration treatment based on optical coherence tomography angiography

The advent of anti-vascular endothelial growth factor (VEGF) therapies has remarkably improved the functional outcomes of neovascular age-related macular degeneration (nAMD) patients. However, there are guidelines on how to start treatment, the guidelines for discontinuing treatment are not yet clear. In this respect, the treat-extend-stop (TES) protocol have showed us the possibility of discontinuing treatment. In this study, we tried to investigate optical coherence tomography angiography (OCTA) biomarkers related to recurrence of neovascular activity in eyes with nAMD undergoing treatment using TES protocol. A total of 134 eyes with nAMD were divided into two groups (stop, non-stop) depending on whether they met criteria for stopping anti-VEGF treatment. Quantitative and qualitative OCTA parameters including the morphologic pattern of choroidal neovascularization (CNV) were compared between groups. Of these, 44 eyes (32.8%) were in the stop group and 90 eyes (67.2%) were in the non-stop group. In multivariate regression analysis, closed-circuit pattern of CNV and the presence of peripheral loop were associated with the non-stop group (all p < 0.001). Our results imply that the morphologic appearance of CNV on OCTA after anti-VEGF treatment may be a useful biomarker to predict weaning from treatment.

Predictors of treatment response to intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy for choroidal neovascularisation secondary to chronic central serous chorioretinopathy

PURPOSE

The aim of this study was to evaluate the effect of anti-vascular endothelial growth factor (VEGF) therapy on choroidal neovascularisation (CNV) complicating central serous chorioretinopathy (CSC) using multimodal imaging, and to identify possible predictive factors of the treatment response.

DESIGN

Retrospective study.

METHODS

Data of 27 eyes with CNV complicating CSC treated with anti-VEGF therapy (either ranibizumab or aflibercept) were reviewed. Response to anti-VEGF treatment was evaluated by change in visual acuity, intra/subretinal fluid modifications and CNV changes on optical coherence tomography angiography (OCTA). Univariate and multivariate analyses were performed to identify predictive factors for central retinal thickness (CRT) change and for the relative degree of treatment response (complete, incomplete or absent fluid reduction).

RESULTS

CRT was significantly reduced at 32±15 days after 2.8±1.3 injections (p=0.0004) as was the subretinal fluid (p=0002). Complete fluid resorption was observed in 45% of cases. Best corrected visual acuity did not significantly improve (p=0.18). CNV area (p=0.09) and CNV flow area (p=0.07) did not significantly decrease. No changes in CNV pattern were noted. Univariate analysis identified greater CRT at baseline (p<0.0001), greater amount of subretinal fluid (p<0.0001), a shorter period of retinal fluid (p=0.04) and female gender (p=0.04) as predictors for CRT reduction. After multivariate analysis the factor of greater CRT at baseline (p<0.0001) proved independent. The degree of treatment response was dependent on the size of CNV surface (p=0.05) and flow area (p=0.05) on OCTA in the univariate analysis, and the latter independent after multivariate analysis. In addition, a shorter time period of retinal fluid appeared to play a role (p=0.01 multivariate, p=0.19 univariate).

CONCLUSION

The anti-VEGF response was highly variable and often incomplete, suggesting that CNV was not solely responsible for the fluid accumulation. Predictive factors may guide indication for anti-VEGF in CNV associated with CSC.

One-Year Outcomes of 1 Dose versus 3 Loading Doses Followed by Pro Re Nata Regimen Using Ranibizumab for Neovascular Age-Related Macular Degeneration: The ARTIS Trial

Purpose. To compare the functional and anatomical outcomes of one dose and three loading doses followed by the pro re nata (PRN) regimen in Chinese neovascular age-related macular degeneration (nvAMD) (including polypoidal choroidal vasculopathy (PCV)) patients. Methods. In this multicenter, prospective, open-label, controlled, 12-month study (ClinicalTrials.gov: NCT02810808), patients were randomized (1 : 1) to 1 dose + PRN (PRN group) or 3 loading doses + PRN (LD group) using intravitreal ranibizumab treatment. Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were evaluated. The main outcome was the change in BCVA. The noninferiority limit was 5 letters. Results. Forty-five patients in the PRN group and 49 patients in the LD group finished 12-month follow-up. Each group included 4 PCV patients. The mean change in BCVA from baseline was 7.8 letters in the PRN group, compared with 10.9 letters in the LD group (P=0.344). There were no significant differences between two groups in the mean change of CRT (−159.3 μm vs. −120.5 μm) at month 12. The mean number of injections during the 12-month follow-up was 6.0 in the PRN group and 6.8 in the LD group. The proportion of patients who gained an improvement in visual acuity by 15 or more letters was 28.9% in the PRN group and 44.9% in the LD group (P=0.066). Conclusion. One dose + PRN showed noninferior visual gains than 3 loading doses + PRN regimen using ranibizumab in Chinese nvAMD and PCV patients. Number of injections in the PRN group was similar as that in the LD group but remained a potential risk of vision instability during one-year follow-up using OCT-guided retreatment criteria. This trial is registered with NCT02810808.

Effect of total anti-VEGF treatment exposure on patterns of choroidal neovascularisation assessed by optical coherence tomography angiography in age-related macular degeneration: a retrospective case series

Objective

To compare clinical characteristics of patients suffering from neovascular age-related macular degeneration (nAMD) with mature and immature choroidal neovascularisation (CNV) as assessed by optical coherence tomography angiography (OCTA). To explore the effect of total anti-vascular endothelial growth factor exposure on the occurrence of mature CNV when correcting for potential confounders.

Methods and analysis

In this retrospective case series, we included 40 eyes of 36 patients with nAMD with CNV assessed by OCTA at the Manchester Eye Hospital between June 2016 and June 2017. A retinal specialist masked to patient information graded CNV depicted on OCTA scans. For statistical comparisons, we used t-tests, Fisher's exact tests and a mixed-effects logistic regression model.

Results

18 patients (20 eyes) were treatment naïve, and the mean number of intravitreal injections (IVI) in the remaining eyes was 18.4 (range 2-71). The mean duration of nAMD was 19.3 months (range 0-87.4). 25 eyes (62.5%) exhibited mature CNV. Eyes with mature CNV did not differ from those with immature CNV regarding age (+2.8 years; p=0.288) or duration of disease (+9.4 months; p=0.061). However, they had a higher number of IVIs (+3.1; p=0.035). Among eyes with best corrected visual acuity over 25 letters, there was a strong association between the number of IVIs (0 vs 1-20: OR 68.01 [95% CI 1.30 to 3546.99; p=0.036], 0 vs >20 IVI: OR 380.01 [95% CI 2.60 to 55 464.89; p=0.019]) and maturity status when correcting for potential confounders.

Conclusion

Maturity status of CNV as assessed by OCTA may indicate treatment exposure of CNV in nAMD.