Vascular density normative data of radial peripapillary capillary plexus in healthy Caucasian subjects.

PURPOSE: To establish a normative database for vascular density (VD) of radial peripapillary capillary plexus (RPC) in healthy Caucasian subjects. METHODS: 633 healthy Caucasian subjects underwent a complete ophthalmological examination, including slit-lamp biomicroscopy, best corrected visual acuity measurement with Early Treatment Diabetic Retinopathy Study charts, intraocular pressure measurement, fundus examination, and macular and optic nerve head (ONH) structural optical coherence tomography (OCT). En-face 4.5 × 4.5 mm OCT angiography scans of the RPC plexus were recorded and VD values, automatically provided by the AngioAnalytics™ software, noted. We statistically estimated the impact of age and gender on RPC VD values using a linear mixed model. RESULTS: 560 subjects fully met inclusion criteria and, according to age, were stratified into 5 groups: 18-50 years (77), 51-60 years (160), 61-70 years (110), 71-80 years (132), and ≥ 81 years (81). Overall, mean RPC VD of the whole en-face image was 53.03 ± 4.27%. Age was significantly related to RPC VD values of whole en-face image (r = -0.454; p < 0.0001), which decreased with aging. The linear mixed model disclosed that age has a statistically significant effect on RPC VD values in whole en-face image (p = 0.0006). As age increases, RPC VD values decrease by 0.12 per year. Conversely, no significant gender-related differences were found in terms of RPC VD values of whole en-face image and each parapapillary quadrant analyzing all age group. CONCLUSIONS: Results show that RPC VD values in healthy Caucasian subjects decrease with aging. These data may be used to create a reference normative database useful for clinical use. KEY MESSAGES: What is known Radial peripapillary capillary (RPC) plexus, consisting of long parallel capillaries with rare bifurcations and anastomosis and extending straight along the course of the retinal nerve fiber layer to the posterior pole, may be affected early in some optic nerve head (ONH) and retinal diseases. What is new This study reports RPC vascular density (VD) values, automatically measured on optical coherence tomography angiography, in healthy Caucasian subjects, demonstrating that age is negatively related to RPC VD values. Results show that RPC VD values in healthy Caucasian subjects decrease with aging. These data may be used to create a reference normative database useful for clinical use.

Optical coherence tomography angiography macular biomarkers of peripheral retinal ischemia in diabetic macular edema: secondary endpoints from the clinical study "FOVEA".

PURPOSE: To investigate the relationship between the macular values of fractal dimension (FD) and lacunarity (LAC) on optical coherence tomography angiography (OCTA) images and the presence of peripheral retina non-perfusion areas (NPAs) on fluorescein angiography (FA) in patients with treatment-naïve diabetic macular edema (DME). METHODS: Fifty patients with treatment-naïve DME underwent a full ophthalmic examination, including best-corrected visual acuity measurement, FA, spectral-domain optical coherence tomography, and OCTA. Specifically, FA was performed to detect the presence of retinal NPAs, whereas fractal OCTA analysis was used to determine macular FD and LAC values at the level of the superficial and deep capillary plexus (SCP and DCP). FA montage frames of the posterior pole and peripheral retina, as well as macular OCTA slabs of the SCP and DCP, were obtained. RESULTS: Thirty (60%) eyes with FA evidence of peripheral retinal NPAs in at least one quadrant showed significantly lower FD and higher LAC in both SCP and DCP, when compared with eyes presenting a well-perfused peripheral retina. Furthermore, macular FD and LAC values were found to be significantly associated with the extent of retinal NPAs. CONCLUSIONS: Macular FD and LAC of both SCP and DCP seem to be strongly associated with the extent of peripheral retinal NPAs, thus suggesting that may be useful predictive biomarkers of peripheral ischemia in treatment-naïve DME eyes.

Predictive Factors of Visual Outcome in Treatment-Naïve Diabetic Macular Edema: Preliminary Results from the Clinical Study "FOVEA".

Diabetic macular edema (DME) is a common cause of vision impairment in diabetic retinopathy. The aim of this study was to analyze the relationship between visual outcome and anatomic changes detected by traditional multimodal retinal imaging and optical coherence tomography angiography (OCTA) in DME eyes under treatment with Aflibercept. METHODS: Sixty-six DME eyes of 62 patients under treatment with intravitreal Aflibercept and with one-year follow-up were enrolled. All participants underwent a full ophthalmic evaluation, including best correct visual acuity (BCVA) measurement, spectral-domain optical coherence tomography, fluorescein angiography and OCTA, both at baseline and final examination. Fractal OCTA analysis of the superficial and deep capillary plexus (SCP and DCP) was performed to estimate vascular perfusion density and lacunarity (LAC). RESULTS: At the final examination, there was a significant improvement in terms of BCVA and central macular thickness (CMT). Furthermore, eyes with CMT <373 µm at baseline reached the higher BCVA at the last follow-up. Eyes with CMT ≥373 µm and DCP LAC <0.41 reached a higher final BCVA, if compared with eyes showing the same CMT but higher initial LAC. CONCLUSION: A 12-month treatment with intravitreal Aflibercept for DME resulted in significant visual and anatomic improvement. Multimodal retinal imaging, together with fractal OCTA analysis, may provide useful biomarkers, predictive of visual outcome in DME.

Final 4-year results of the RAINBOW real-world study: intravitreal aflibercept dosing regimens in France in treatment-naïve patients with neovascular age-related macular degeneration.

PURPOSE: The purpose of this study is to evaluate real-world treatment outcomes in patients with neovascular age-related macular degeneration (nAMD) treated with intravitreal aflibercept (IVT-AFL) in routine clinical practice in France. METHODS: RAINBOW (NCT02279537) was an ambispective, observational, 4-year study assessing IVT-AFL effectiveness, treatment patterns, and safety in patients with nAMD in France. Treatment-naïve patients prescribed IVT-AFL and treated according to local practice (pro re nata or treat-and-extend) were eligible. Three treatment cohorts were retrospectively identified based on their treatment pattern within the first 12 months: regular (3 initial monthly IVT-AFL injections received within 45-90 days after the first injection in month 0 and followed by injections every 2 months), irregular with the initial monthly injections, and irregular without the initial monthly injections. The primary endpoint was mean change in best-corrected visual acuity (BCVA) from baseline to month 12. The 48-month results are described here. RESULTS: Overall, the study included 516 patients (each with one study eye), and 30.2% of patients completed 48 months of IVT-AFL treatment. Mean change in BCVA from baseline (56.5 letters) to month 48 for patients with an assessment at both time points was + 1.1 (regular cohort, n = 47), + 0.1 (irregular cohort with initial monthly injections, n = 115), and - 1.3 letters (irregular cohort without initial monthly injections, n = 26), representing a decrease from the gains achieved at month 12. Mean number of IVT-AFL injections received by month 48 in the treatment cohorts was 14.9, 13.7, and 11.9, respectively. The safety profile of IVT-AFL was consistent with previous studies. CONCLUSION: In RAINBOW, the 48-month results demonstrate a lack of long-term effectiveness of IVT-AFL treatment of nAMD due to progressive undertreatment in routine clinical practice in France. These real-world findings highlight the importance of 3 initial monthly IVT-AFL injections followed by continuous proactive treatment beyond the first year to achieve optimal functional outcomes. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT02279537.

Polygenic risk score and biochemical/environmental variables predict a low-risk profile of age-related macular degeneration in Sardinia.

PURPOSE: To ascertain the prevalence and clinical and genetic features of age-related macular degeneration (AMD) in subjects living in the Lanusei valley, Central Sardinia, Italy, involved in a study on ageing (SardiNIA project). METHODS: A total of 814 volunteers aged ≥ 50 years, randomly selected from the SardiNIA project dataset, were included. A color fundus (CF) photograph of the 30° central retina of each eye was obtained and graded according to the Age-Related Eye Disease Study system. Life-style choices were investigated using standardized questionnaires. The concentrations of several inflammatory biomarkers (i.e., complement component, fibrinogen, and C-reactive protein) were measured. Polygenic risk score (PRS) was calculated and compared with results obtained from a European cohort. RESULTS: A total of 756 subjects had gradable CF photographs for AMD detection. In 91.3%, no signs of AMD were observed. The prevalence rates of early and late AMDs were 6.9% and 0.6%, respectively. A total of 85% of subjects were physically active; only 13.5% were current smokers. Low concentrations of complement component, fibrinogen, and C-reactive protein were found. We calculated the polygenic risk scores (PRS) using 40 AMD markers distributed on several candidate genes in Europeans and Sardinians. The mean PRS value was significantly lower in Sardinians than in the Europeans (0.21 vs. 0.248, respectively, p = 1.18 × 10-77). CONCLUSIONS: In our cohort, most subjects showed no sign of any AMD type and late AMD was a condition rarely observed. Results of genetic, biochemical, and life-style investigation support the hypothesis that Sardinia population may present of a peculiar background with a protective effect against AMD development.

Evaluation of Radial Peripapillary Capillary Density in G6PD Deficiency: An OCT Angiography Pilot Study.

Glucose-6-phosphate-dehydrogenase (G6PD) deficiency is an inherited enzymatic disorder causing hemolytic anemia. The purpose of this pilot study was to compare vascular density (VD) values of the radial peripapillary capillary (RPC) plexus in G6PD-deficient and G6PD-normal men, using optical coherence tomography angiography (OCTA). METHODS: 46 G6PD-deficient men and 23 age-matched male controls were included. A complete ophthalmological evaluation, consisting of slit-lamp biomicroscopy, best-corrected visual acuity, intra-ocular pressure measurement, structural optical coherence tomography, and OCTA scanning of the optic nerve head, was performed. The en-face angioflow images were carefully analyzed and the VD values of the RPC plexus were measured using the AngioAnalytics™ software embedded in the OCTA device. Medical conditions, including systemic hypertension, hypercholesterolemia, and diabetes mellitus, were also investigated. RESULTS: G6PD-deficient eyes showed higher values of VD in all peripapillary sectors, but a statistical significance (p = 0.03) was reached only in the infero-temporal sector. There were no significant differences in terms of hypercholesterolemia, systemic arterial hypertension, and diabetes mellitus between the two study groups. CONCLUSION: Results show that VD values of the RPC plexus are higher in G6PD-deficient men than in G6PD-normal subjects, but a statistically significant difference was found only in the inferior temporal sector. Overall, our preliminary findings support the hypothesis that the RPC layer of G6PD-deficient men consists of a denser vascular network, which may contribute to offering protection against ocular atherosclerotic vasculopathies.

POLYPOIDAL CHOROIDAL NEOVASCULARIZATION VERSUS TYPE 1 CHOROIDAL NEOVASCULARIZATION IN AGE-RELATED MACULAR DEGENERATION: A Fractal Analysis Study.

PURPOSE: To compare quantitative optical coherence tomography angiography parameters between polypoidal choroidal neovascularizations (PCNVs) and Type 1 choroidal neovascularizations (CNVs) in patients with age-related macular degeneration. METHODS: PCNV and Type 1 CNV lesions were retrospectively recruited in a cohort of patients with age-related macular degeneration. All the patients underwent a comprehensive ophthalmic evaluation, including best-corrected visual acuity, fluorescein and indocyanine green angiography, structural optical coherence tomography (OCT), and optical coherence tomography angiography.Vascular perfusion density, fractal dimension, and lacunarity were computed by means of fractal analysis of neovascular en face optical coherence tomography angiography slabs. RESULTS: Sixty-eight eyes were included in the analysis. Of them, 35 of 68 eyes (51.5%) had PCNV and 33 of 68 (48.5%) had Type 1 CNV. Patients with PCNV were significantly younger (P = 0.0003) and had a higher best-corrected visual acuity (P < 0.0001). The mean vascular perfusion density was 0.83 ± 0.11% in PCNVs and 0.46 ± 0.10% in Type 1 CNVs (P < 0.0001). The mean fractal dimension was 1.44 ± 0.1 in PCNVs and 1.45 ± 0.09 in Type 1 CNVs (P = 0.86) while the mean lacunarity was 2.46 ± 1.03 in PCNVs and 1.86 ± 0.52 in Type 1 CNVs (P = 0.006). CONCLUSION: PCNVs resulted to be more heterogeneous and characterized by higher vascular perfusion density and lacunarity values than Type 1 CNVs. These interesting findings seem to support the idea that PCNVs and Type 1 CNVs are two separate clinical entities. However, future studies based on optical coherence tomography angiography fractal analysis, but also involving other relevant parameters such as demographics, presentation, morphology on multimodal imaging, and response to treatment, are necessary before drawing any definitive conclusions on whether PCNV is a specific clinical entity or a neovascular age-related macular degeneration variant.

OCT Angiography Fractal Analysis of Choroidal Neovessels Secondary to Central Serous Chorioretinopathy, in a Caucasian Cohort.

Central serous chorioretinopathy (CSCR) can be complicated by different types of choroidal neovascularization (CNV). The purpose of this study was to investigate the incidence and quantitative optical coherence tomography angiography (OCT-A) features of CSCR-related CNVs. METHODS: This was a retrospective multicenter study including 102 eyes of 102 Caucasian patients with acute or complex CSCR. All patients underwent a comprehensive ophthalmological examination. Quantitative OCT-A parameters, including vascular perfusion density (VPD), fractal dimension (FD), and lacunarity (LAC), were measured in CNV eyes. RESULTS: Forty eyes (39.2%) had acute CSCR, whereas the remaining sixty-two (60.8%) had complex CSCR. CNV was observed in 37 (36.27%) eyes, all of which had the complex form. CNVs were classified as type 1 CNV in 11/37 (29.73%) cases and as polypoidal choroidal vasculopathy (PCV) in the remaining 26/37 (70.27%). Overall, the mean VPD, FD, and LAC of CSCR-related CNVs were 0.52 ± 0.20%, 1.44 ± 0.12, and 2.40 ± 1.1, respectively. No significant difference between type 1 CNV and PCV was found. CONCLUSION: Complex CSCR is often complicated by type 1 CNV and PCV with similar neovascular architecture and branching complexity, a finding supporting the idea that they might be different stages of the same neovascular process. Future OCT-A fractal analysis-based studies that also include other relevant parameters, such as demographics, presentation, morphology on multimodal imaging, and response to treatment, are necessary before drawing any definitive conclusions.

Uveitis associated with cancer immunotherapy: long-term outcomes.

Background: We report the long-term outcome of uveitis associated with cancer immunotherapy (CIT). Methods: This retrospective review included serial patients with CIT-associated uveitis treated using various regimen. Results: Eight patients treated with rituximab (anti-CD20), nivolumab (anti-PD-1), ipilimumab (anti-CTLA-4), vemurafenib and dabrafenib (anti-BRAF), trametinib (anti-MEK) and ibritunib showed uveitis with hypopion (one patient), macular edema (five patients) and choroiditis (two patients). Various regimens of corticosteroid therapy showed a favorable ophthalmological outcome, whether the CIT was continuing or suspended. Conclusion: Local corticosteroid injections in combination with CIT could be suggested as a first-line treatment. This could help to preserve the quality of life without threatening the vital prognosis.

Lay abstract This study aims to report the long-term outcome of intra-ocular inflammation (uveitis) associated with cancer immunotherapy (CIT). Serial patients complaining of blurred vision and painful eyes showed intra-ocular inflammation that was related to CIT, after infectious, inflammatory and tumoral causes of uveitis have been ruled out. The length of follow-up was more than 12 months for most patients. Eight serial patients treated with rituximab (anti-CD20), nivolumab (anti-PD-1), ipilimumab (anti-CTLA-4), vemurafenib and dabrafenib (anti-BRAF), trametinib (anti-MEK) and ibritunib showed intra-ocular inflammation with hypopion (one patient), macular edema (five patients) and choroiditis (two patients). Various regimens of corticosteroid therapy showed a favorable ophthalmological outcome, whether the CIT was continuing or suspended. Local corticosteroid injections in combination with CIT could be suggested as a first-line treatment. This could help to preserve the quality of life without threatening the vital prognosis.

The role of future treatments in the management of neovascular age-related macular degeneration in Europe.

Anti-vascular endothelial growth factor (VEGF) agents have transformed the management of patients with neovascular age-related macular degeneration (nAMD) over the past two decades. However, as more long-term real-world data become available, it is clear that treatment outcomes are inferior to those reported in large, controlled clinical trials. This is largely driven by undertreatment, that is, not maintaining a consistent injection frequency to achieve sustained VEGF suppression, whether due to patient non-compliance, an important injection burden, or non/incomplete anatomical response. Newer therapeutic advances under evaluation hold promise in achieving more, for less. We review the latest drugs currently in or having successfully finished phase III clinical trials, and determine their potential place in the management of patients with nAMD in Europe.

Fractal analysis of polypoidal choroidal neovascularisation in age-related macular degeneration.

AIM: To describe optical coherence tomography angiography (OCTA) features of polypoidal choroidal neovascularisation (PCNV) secondary to age-related macular degeneration. METHODS: A retrospective consecutive series of 51 patients with a diagnosis of PCNV, based on clinical and multimodal imaging, was analysed. All patients with PCNV underwent a comprehensive ophthalmological examination, including fluorescein and indocyanine green angiography, structural optical coherence tomography (OCT) and OCTA. Two blinded retinal specialists carefully reviewed OCTA slabs in order to assess the morphological patterns of PCNV lesions. Furthermore, fractal analysis of PCNV en face images on OCTA, including vascular perfusion density (VPD), fractal dimension (FD) and lacunarity (LAC), was performed. RESULTS: Fifty-one PCNV eyes were included in the study. In all, the branching vascular network appeared hyper-reflective. Polyps showed two different patterns: in 34/51 (67%) eyes, they corresponded to hypo-reflective structures, whereas in the remaining 17 (33%) eyes, they appeared as hyper-reflective lesions. In all PCNV eyes, mean VPD, FD and LAC were 0.76±0.17%, 1.46±0.12 and 2.4±0.87, respectively. No significant difference was found between PCNVs showing a different OCTA pattern, in terms of quantitative OCTA parameters. CONCLUSION: Fractal analysis provides quantitative parameters demonstrating that PCNVs with different OCTA patterns share the same neovascular architecture and branching complexity. These new findings improve our ability to interpret OCTA slabs, opening new areas of discussion about this type of neovascular lesion.

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.

Detection of serum uric acid in primary open angle glaucoma: A pilot study.

PURPOSE: To assess the association between the serum levels of uric acid (UA) and primary open-angle glaucoma (POAG). METHODS: In this pilot study, 46 eyes of 23 patients with a clinical history of POAG and 30 eyes of 15 healthy subjects were included. All patients underwent a complete ophthalmological examination, including best corrected visual acuity (BCVA), intraocular pressure (IOP), and gonioscopy. Visual field parameters, such as mean deviation (MD) and pattern standard deviation (PSD), and optical coherence tomography (OCT) values of the optic nerve head, including retinal nerve fiber layer (RNFL) thickness and vertical cup/disc ratio (VCDR), were noted. A blood sample was collected from each subject for serum UA measurement. RESULTS: IOP, MD, PSD, RNFL thickness, and VCDR resulted significantly different in POAG patients, when compared with controls (p < 0.05). POAG patients showed significantly lower levels of mean serum UA than healthy controls (4.00 ± 0.66 mg/dL vs 4.95 ± 0.86 mg/dL, respectively, p < 0.0001). Furthermore, severe POAG patients showed mean serum levels of UA lower than mild POAG patients (3.36 ± 0.70 mg/dL vs 4.22 ± 0.51 mg/dL, respectively, p = 0.01). Visual field and OCT parameters were statistically correlated with the mean serum levels of UA in POAG eyes (p < 0.05). CONCLUSION: Results suggest that in POAG patients, serum UA levels may be decreased and correlated with visual field and OCT parameters worsening. Further larger multi-center prospective studies are necessary to confirm our findings and establish the role of UA in glaucoma.

OCT-Angiography as a reliable prognostic tool in laser-treated proliferative diabetic retinopathy: The RENOCTA Study.

PURPOSE: To quantitatively assess retinal neovascularizations (RNVs) in proliferative diabetic retinopathy (PDR) before and after photocoagulative laser treatment (PLT) using Optical Coherence Tomography Angiography (OCT-A). METHODS: Consecutive patients with PDR were examined with fluorescein angiography (FA) and OCT-A before and after PLT. Baseline and after-treatment FA images were quantitatively analyzed to assess both the RNVs area and leakage area. On OCT-A RNVs area, vascular perfusion density (VPD), vessel length density (VLD) and fractal dimension were computed. VPD of the full-retina OCT-A underneath the RNV was determined to evaluate potential laser-induced changes in vascular perfusion. RESULTS: Fifteen eyes of 13 patients with PDR were enrolled. The mean area of the RNVs was 0.47 ± 0.50 mm2 in the baseline OCT-A and 0.32 ± 0.40 mm2 in the post-treatment assessment (p = 0.0002). The mean RNV VPD of RNV was 2% ± 4% in pre-treatment and 1% ± 1% for the post-treatment (p = 0.0001). The mean VLD of RNV was 7.26 ± 1.53 at baseline and 6.64 ± 1.65 in the post treatment (p = 0.0002). A significant difference in terms of mean RNVs area and VPD reduction between eyes that needed additional treatment and those that did not (~40% vs ~20%; p < 0.05), was observed. Mean VPD of full-retinal thickness OCT-angiogram was 55% ± 10% for the pre-treatment and 53% ± 8% for the post treatment scan (p = 0.02). CONCLUSION: The quantitative OCT-A assessment of laser-induced changes of RNVs can be a useful non-invasive approach for determining treatment efficacy. A reduction of RNVs area or VPD ⩾ 40% might reveal those eyes that won't require additional treatment. Retinal perfusion impairment seemed to progress independently from the treatment.

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 Biomarkers in a Treat-and-Extend Dosing Regimen in Neovascular Age-Related Macular Degeneration.

Purpose: To evaluate the association between quantitative optical coherence tomography angiography (OCT-A) parameters and clinical outcomes in treatment-naïve neovascular age-related macular degeneration (nAMD) patients treated with a treat-and-extend dosing regimen on a 12-month follow-up interval. Methods: Observational, prospective study of consecutive patients. The treatment protocol was based on a loading dose of three anti-vascular endothelial growth factor (VEGF) intravitreal injections (IVI) followed by a treat-and-extend regimen. Eyes were evaluated by swept-source OCT-A at baseline, 1 month after the loading dose and at 12 months. A quantitative analysis was issued for fractal dimension (FD), lacunarity index (LAC), blood flow surface area (SA), and vessel density (VD). An association of these parameters with the anatomic response and functional responses, and IVI number at 12 months of follow-up was assessed. A level of significance α = 0.05 was considered. Results: Sixty-four patients were included, 52 of whom (81%) completed the 12-month study protocol. The median number of injections at 12 months was 7 (P25-P75: 6-12). FD and SA were reduced 1 month after the loading dose of anti-VEGF (P < 0.001). The generalized linear models using baseline FD and baseline SA achieved the best performance in discriminating a lower treatment burden (area under the curve [AUC] = 0.78; 95% confidence interval [CI]: 0.64-0.91 and AUC = 0.76; 95% CI: 0.63-0.90, respectively). Conclusions: Baseline OCT-A may provide useful biomarkers for the treatment burden in nAMD. Translational Relevance: The application of fractal dimension and automatic blood flow area algorithms to OCT-A data can distinguish patients with distinct treatment burdens in the first year of nAMD.

Volume Rendering of Dense B-Scan Optical Coherence Tomography Angiography to Evaluate the Connectivity of Macular Blood Flow.

Purpose: To characterize macular blood flow connectivity using volume rendering of dense B-scan (DB) optical coherence tomography angiography (OCTA) data. Methods: This was a prospective, cross-sectional, observational study. DB OCTA perifoveal scans were performed on healthy subjects using the Spectralis HRA+OCT2. A volumetric projection artifact removal algorithm and customized filters were applied to raw OCTA voxel data. Volume rendering was performed using a workflow on Imaris 9.5 software. Vascular graphs were obtained from angiographic data using the algorithm threshold-loops. Superficial arteries and veins were identified from color fundus photographs and connections between adjacent arteries and veins displayed using the shortest path algorithm. Connective pathway locations were analyzed with cross-sectional OCT and OCTA to determine their course through the superficial vascular complex (SVC) and the deep vascular complex (DVC). Results: Fourteen eyes from seven subjects (mean age: 28 ± 5 years; 3 women) were included in this analysis. One hundred and twenty-six vascular connections were analyzed. In all cases, the shortest path connections between superficial arteries and veins coursed through the DVC. We did not identify shortest path connections confined to the SVC. Conclusions: Volumetric analysis of vascular connectivity supports a predominantly in-series arrangement of blood flow between the SVC and DVC within the human perifoveal macula.

Impact of intravitreal aflibercept dosing regimens in treatment-naïve patients with neovascular age-related macular degeneration in routine clinical practice in France: results from the RAINBOW study.

OBJECTIVE: To evaluate 12-month outcomes in treatment-naïve patients with neovascular (wet) age-related macular degeneration (AMD) stratified by intravitreal aflibercept (IVT-AFL) regimen. METHODS AND ANALYSIS: Patients included in the 12-month interim analysis of Real life of intravitreal Aflibercept In FraNce: oBservatiOnal Study in Wet AMD (RAINBOW), a 4-year, ongoing observational study conducted in France, were stratified by IVT-AFL dosing regimen. Safety (n=593) and effectiveness (n=428) data were analysed. Regimens included a regular cohort (three initial monthly IVT-AFL injections and ≥6 injections) and irregular cohorts (<6 injections) with and without three initial monthly injections. The main outcome measure was mean gain in best-corrected visual acuity (BCVA) at 12 months. RESULTS: Mean number of IVT-AFL injections was 6.0 (all patients, n=513), 7.2 (regular cohort, n=102), 6.1 (irregular cohort with three initial monthly injections, n=266) and 5.2 (irregular cohort without three initial monthly injections, n=60). Overall mean gain in BCVA at 12 months was 5 letters; +7.1 letters (regular cohort) and +5.6 letters (irregular cohort with three initial monthly injections), both p<0.001 versus baseline, and -1.1 letters (irregular cohort without three initial monthly injections), p=0.669. Improvements in BCVA were also significantly greater in the regular cohort (p<0.001) and irregular cohort with three initial monthly injections (p=0.003) compared with the irregular cohort without three initial monthly injections. Ocular and non-ocular adverse events were reported in 14.7% and 17.4% of all patients, respectively. CONCLUSION: Treatment-naïve patients with neovascular AMD receiving three initial monthly injections followed by regular or irregular injections over 12 months experienced better visual acuity outcomes than those receiving irregular treatment without three initial monthly injections. TRIAL REGISTRATION NUMBER: NCT02279537.

Impact of intravitreal aflibercept dosing regimens in treatment-naïve patients with neovascular age-related macular degeneration: 2-year results of RAINBOW.

BACKGROUND: To review treatment outcomes from real-world data of patients with neovascular age-related macular degeneration (nAMD) treated with intravitreal aflibercept (IVT-AFL) injection. METHODS: RAINBOW (ClinicalTrials.gov, NCT02279537) is an ongoing, observational, 4-year study to monitor the effectiveness and safety of IVT-AFL in patients with nAMD in clinical practice in France. Treatment-naïve patients diagnosed with nAMD who had been prescribed IVT-AFL by their treating physician were eligible. The regimens of interest were regular treatment interval cohort (patients who received three initial monthly IVT-AFL injections followed by regular injections every 2 months) and two irregular treatment interval cohorts (with and without three initial monthly injections). Here we describe results at 24 months in patients according to IVT-AFL treatment regimen. RESULTS: The mean change in best-corrected visual acuity (BCVA) with IVT-AFL from baseline to 24 months was + 3.0 letters in the overall population (P < 0.05 vs baseline). The mean change was positive for the regular and irregular treatment interval cohorts with initial doses (+ 4.9 and + 4.0 letters, respectively; P < 0.05 vs baseline) and negative for the irregular treatment interval cohort without initial doses (- 2.5 letters; P = 0.365 vs baseline) at 24 months. The mean overall number of IVT-AFL injections over 12 and 24 months was 6.0 and 8.8, respectively. The most common ocular adverse events were lack of efficacy (6.3%), vitreous floaters (2.7%), and increased lacrimation (1.7%). CONCLUSIONS: In the real-world RAINBOW study, visual outcomes observed at 24 months were consistent with results from the primary endpoint at 12 months. In this study, treatment-naïve patients who received three initial IVT-AFL doses and regular IVT-AFL treatment over the first 24 months experienced better visual outcomes than patients who received no initial doses and an irregular treatment regimen. TRIAL REGISTRATION: www.ClinicalTrials.gov (NCT02279537). Registered 29 October 2014.

Functional correlation between choroidal and retinal vascularity in low-grade diabetic retinopathy.

AIMS: To perform an automated functional assessment of retinal and choroidal microvasculature in eyes with low-grade diabetic retinopathy (DR) using optical coherence tomography angiography (OCT-A) and to identify potential perfusion changes in case of early vascular damage. METHODS: This is an observational, case-control study of consecutive diabetic patients with level 20 DR severity scale score and age-matched healthy subjects. A prototypal OCT-angiography was used to obtain the OCT-angiograms of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC) layer. A validated automated microstructural analysis provided data on SCP, DCP and CC vascular perfusion density (VPD). A comparative assessment between different vascular layers and different groups was performed. RESULTS: Twenty-nine diabetic patients (7 females, 24%) and 20 healthy controls were enrolled. VPD values were significantly lower in the DCP (25.1% vs. 26.5%; p = 0.04) and CC (71.2% vs. 86.6%; p = 0.0001) of diabetic patients compared with controls. A statistically significant negative linear correlation was reported between CC VPD and DCP VPD in diabetic patients; at the reverse, a positive linear correlation between the same parameters was noticed in controls. CONCLUSION: Retinal and choroidal vascular networks, although distinct entities, seem functionally interconnected: varying the degree of perfusion may be a mutual compensatory mechanism in response to an ischemic injury.