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.

FLUID-BASED VISUAL PROGNOSTICATION IN TYPE 3 MACULAR NEOVASCULARIZATION-FLIP-3 STUDY.

PURPOSE: To analyze the effect of fluid on visual acuity in cases of Type 3 macular neovascularization. METHODS: This multicentric, retrospective cohort study included eyes with treatment-naïve Type 3 macular neovascularization. Analysis of fluid in different compartments was performed. Group A included eyes with isolated intraretinal fluid, whereas Group B included eyes with intraretinal fluid in conjunction with subretinal fluid and/or sub retinal pigment epithelial fluid. RESULTS: Eyes in Group A (31, 55.3%) had better best-corrected visual acuity of 20/50 snellen equivalent (0.42 ± 0.31 logarithm of the minimum angle of resolution) at baseline and 20/50 snellen equivalent (0.40 ± 0.28 logarithm of the minimum angle of resolution) at complete resolution compared with Group B with visual acuity of 20/80 snellen equivalent (0.64 ± 0.35 logarithm of the minimum angle of resolution) (P = 0.0181) at baseline and 20/100 snellen equivalent (0.70 ± 0.40 logarithm of the minimum angle of resolution) (P = 0.0021) at complete resolution. Subfoveal atrophy was more in Group B (82.6% 19/23) at complete resolution in comparison to Group A (16/31, 51.6%). Eyes in Group B needed more anti-vascular endothelial growth factor injections (10.3 ± 9.0) for complete resolution compared with Group A (5.7 ± 4.8). CONCLUSION: Intraretinal fluid may be associated with good visual acuity in Type 3 macular neovascularization in contrast to other forms of neovascular age related macular degeneration. Furthermore, intraretinal fluid in isolation may need fewer injections and could probably be associated with less subfoveal atrophy.

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

PURPOSE: To evaluate the morphologic features of macular neovascularization (MNV) trunks at different layers using optical coherence tomography angiography. METHODS: Type 1 MNV trunks in age-related macular degeneration were retrospectively evaluated at the subretinal pigment epithelium and sub-Bruch membrane (subBM) layers. The detectability and location of the trunks were compared. MNV trunks at the subBM layer on optical coherence tomography angiography B-scans were evaluated using a flow overlay. The correlations of the MNV trunk with optical coherence tomography angiography and optical coherence tomography parameters were evaluated. RESULTS: Among the 63 included eyes, 27 showed core vessels at the subretinal pigment epithelium layer and 52 showed MNV trunks at the subBM layer, which were connected with the MNV at the subretinal pigment epithelium layer. The locations of the MNV trunks in each layer were different. MNV trunk types at the subBM layer were related to disease duration, distance from the large choroidal vessels, and MNV vessel density. The large choroidal vessel diameter was correlated with the MNV trunk diameter at the subBM layer. CONCLUSION: Macular neovascularization trunks at the subBM layer were detected more frequently than distal MNV trunks at the subretinal pigment epithelium layer. Macular neovascularization trunk features at the subBM layer may be related to disease duration and a large choroidal vessel.

Lack of WWC2 Protein Leads to Aberrant Angiogenesis in Postnatal Mice.

The WWC protein family is an upstream regulator of the Hippo signalling pathway that is involved in many cellular processes. We examined the effect of an endothelium-specific WWC1 and/or WWC2 knock-out on ocular angiogenesis. Knock-outs were induced in C57BL/6 mice at the age of one day (P1) and evaluated at P6 (postnatal mice) or induced at the age of five weeks and evaluated at three months of age (adult mice). We analysed morphology of retinal vasculature in retinal flat mounts. In addition, in vivo imaging and functional testing by electroretinography were performed in adult mice. Adult WWC1/2 double knock-out mice differed neither functionally nor morphologically from the control group. In contrast, the retinas of the postnatal WWC knock-out mice showed a hyperproliferative phenotype with significantly enlarged areas of sprouting angiogenesis and a higher number of tip cells. The branching and end points in the peripheral plexus were significantly increased compared to the control group. The deletion of the WWC2 gene was decisive for these effects; while knocking out WWC1 showed no significant differences. The results hint strongly that WWC2 is an essential regulator of ocular angiogenesis in mice. As an activator of the Hippo signalling pathway, it prevents excessive proliferation during physiological angiogenesis. In adult animals, WWC proteins do not seem to be important for the maintenance of the mature vascular plexus.

Case Report: Peripheral Retinal Ischemia and Retinal Neovascularization in von Willebrand Disease.

SIGNIFICANCE: Although von Willebrand disease is the most common inherited bleeding disorder, there are only a few published reports of ocular complications. To our knowledge, this is the first case of peripheral retinal ischemia and retinal neovascularization in a patient with von Willebrand disease. PURPOSE: This study aimed to demonstrate the value of multispecialty care when exploring a diagnosis for bilateral retinopathy. CASE REPORT: A 55-year-old African American woman presented with peripheral retinal hemorrhages on routine examination. She was asymptomatic and did not have any personal or family history of bleeding disorders. Blood work was ordered, and she was referred to a retinal specialist who found peripheral telangiectasia, retinal ischemia, and leakage on fluorescein angiography, consistent with retinal neovascularization. Laser photocoagulation was performed while numerous specialists were consulted to determine the cause for her retinopathy. Laboratory testing confirmed low-grade type 1 von Willebrand disease. She was monitored without systemic treatment. She remained stable and asymptomatic, but her retinal neovascularization did not regress fully, so laser treatment was repeated. CONCLUSIONS: This case described a new finding of peripheral retinal ischemia and retinal neovascularization in von Willebrand disease. It was discovered in an asymptomatic patient who did not have a history of bleeding but presented with bilateral retinal hemorrhages. Diagnosis was challenging because of the high degree of variation in this bleeding disorder, requiring extensive testing and careful consideration of the individual's clinical profile. Most people with von Willebrand disease do not know they have the disease because symptoms are mild or absent, so most cases are unreported. The von Willebrand factor is poorly recognized in ocular disease, but given its role in angiogenesis, it may be a valuable target to consider in future research.

Interferon-γ inhibits retinal neovascularization in a mouse model of ischemic retinopathy.

Interferon-γ (IFNG) is one of the key cytokines that regulates both innate and adaptive immune responses in the body. However, the role of IFNG in the regulation of vascularization, especially in the context of Vascular endothelial growth factor A (VEGFa)-induced angiogenesis is not clarified. Here, we report that IFNG shows potent anti-angiogenic potential against VEGFa-induced angiogenesis. IFNG significantly inhibited proliferation, migration, and tube formation of Human umbilical vein endothelial cells (HUVECs) both under basal and VEGFa-treated conditions. Intriguingly, Knockdown (KD) of STAT1 abolished the inhibitory effect of IFNG on VEGFa-induced angiogenic processes in HUVECs. Furthermore, IFNG exhibited potent anti-angiogenic efficacy in the mouse model of oxygen-induced retinopathy (OIR), an in vivo model for hypoxia-induced retinal neovascularization, without induction of functional side effects. Taken together, these results show that IFNG plays a crucial role in the regulation of VEGFa-dependent angiogenesis, suggesting its potential therapeutic applicability in neovascular diseases.

Prostaglandin E2 promotes pathological retinal neovascularisation via EP4R-EGFR-Gab1-AKT signaling pathway.

Proliferative retinopathies, such as proliferative diabetic retinopathy (PDR) and retinopathy of prematurity (ROP) are major causes of visual impairment and blindness in industrialized countries. Prostaglandin E2 (PGE2) is implicated in cellular proliferation and migration via E-prostanoid receptor (EP4R). The aim of this study was to investigate the role of PGE2/EP4R signaling in the promotion of retinal neovascularisation. In a streptozotocin (STZ)-induced diabetic model and an oxygen-induced retinopathy (OIR) model, rats received an intravitreal injection of PGE2, cay10598 (an EP4R agonist) or AH23848 (an EP4R antagonist). Optical coherence tomography, retinal histology and biochemical markers were assessed. Treatment with PGE2 or cay10598 accelerated pathological retinal angiogenesis in STZ and OIR-induced rat retina, which was ameliorated in rats pretreated with AH23848. Serum VEGF-A was upregulated in the PGE2-treated diabetic rats vs non-treated diabetic rats and significantly downregulated in AH23848-treated diabetic rats. PGE2 or cay10598 treatment also significantly accelerated endothelial tip-cell formation in new-born rat retina. In addition, AH23848 treatment attenuated PGE2-or cay10598-induced proliferation and migration by repressing the EGF receptor (EGFR)/Growth factor receptor bound protein 2-associated binder protein 1 (Gab1)/Akt/NF-κB/VEGF-A signaling network in human retinal microvascular endothelial cells (hRMECs). PGE2/EP4R signaling network is thus a potential therapeutic target for pathological intraocular angiogenesis.

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

PURPOSE: To quantitatively analyze choriocapillaris alterations using swept-source optical coherence tomography angiography in eyes presenting with Type 3 macular neovascularization (MNV) and to compare these alterations with eyes presenting with intermediate AMD (iAMD). METHODS: Macular 3 × 3-mm swept-source optical coherence tomography angiography scans were retrospectively analyzed in eyes with Type 3 MNV and in eyes with iAMD. The choriocapillaris en face slabs were extracted from the swept-source optical coherence tomography angiography device after manual segmentation. En face choriocapillaris flow images were compensated with en face choriocapillaris structure images, followed by the Phansalkar local thresholding method using a window radius of 4 and 8 pixels. The percentage of flow deficits (FD%), the number, size, and total area of FDs were computed for comparison. A secondary analysis was performed in the four corners of the image to include equidistant regions in all eyes. RESULTS: Twenty-six Type 3 MNV eyes of 21 patients and 26 iAMD eyes of 17 patients were included. Compared with iAMD eyes, eyes with Type 3 MNV displayed a higher FD% (41.37% ± 14.74 vs. 19.80% ± 9.63 using radius 4 pixels [P < 0.001]; 45.24% ± 11.9 vs. 26.63% ± 8.96 using radius 8 pixels [P < 0.001]). The average size of FDs was significantly larger in Type 3 MNV eyes compared with iAMD eyes (P < 0.001), whereas the number of FDs was significantly lower in Type 3 MNV compared with iAMD eyes (P < 0.001). CONCLUSION: Type 3 MNV eyes present with increased choriocapillaris flow impairment compared with iAMD eyes. Reduced choriocapillaris perfusion may contribute to Type 3 MNV development and pathogenesis.

OCT-A characterisation of recurrent type 3 macular neovascularisation.

PURPOSE: To investigate optical coherence tomography angiography (OCT-A) findings in recurrent type 3 macular neovascularisation (MNV). METHODS: In this retrospective cohort study, consecutive patients with type 3 MNV secondary to age-related macular degeneration underwent OCT-A at three different time points: baseline, after anti-vascular endothelial growth factor treatment with complete resolution of the exudative signs (ie, non-exudative stage) and at the recurrence of exudation (ie, recurrence stage). Demographics and clinical findings were analysed, including OCT-A features of type 3 MNV recurrence. RESULTS: Twelve eyes (12 patients, mean age 78±7 years) were included. Using OCT-A, at baseline all type 3 MNVs showed the presence of detectable flow downgrowing from the deep vascular complex (DVC) to the retinal pigment epithelium (RPE)/sub-RPE space. 6/12 eyes (50%) showed anomalous flow under the RPE, while the other 6 eyes showed flow reaching the RPE without anomalous flow in the sub-RPE space. At the non-exudative stage (after treatment), BCVA and CMT significantly improved (p=0.004 and p=0.036), and flow inside the retinal lesions reduced; interestingly the connection to the RPE/sub-RPE space regressed. At the time of recurrence, all type 3 MNVs showed the presence of intra/sub-retinal exudation with restoration of the flow deepening from the DVC to the RPE/sub-RPE space. CONCLUSIONS: Detectable flow deepening from the DVC to the RPE/sub-RPE space using OCT-A is mandatory to have a new exudation secondary to recurrent type 3 MNV. Early detection of type 3 MNV recurrence by OCT-A characterisation may prompt retreatment and potentially prevent progression to late stages of the disease.

Comparison of macular neovascularization lesion size by the use of Spectral-Domain Optical Coherence Tomography Angiography and Swept-Source Optical Coherence Tomography Angiography versus Indocyanine Green Angiography.

PURPOSE: To compare the lesion sizes of macular neovascularization (MNV) imaged with spectral-domain (SD) and swept-source (SS) optical coherence tomography angiography (OCTA) as well as indocyanine green angiography (ICGA). METHODS: In this prospective, observational case series, patients showing a secured diagnosis of MNV on ICGA or Fluorescein Angiography, were imaged by SD-OCTA and SS-OCTA on the same day. Lesion size was measured on 3 × 3-mm2 and 6 × 6-mm2 scans using the Maestro 2 SD-OCTA (Topcon Corporation, Tokyo Japan) and the Triton SS-OCTA device (Topcon Corporation, Tokyo Japan) and compared to ICGA (Spectralis HRA, Heidelberg, Germany). RESULTS: Twenty eyes from 20 patients (11 females, 55%) were enrolled. The neovascularization area measured on 6 × 6-mm2 SD-OCTA was lower compared to that outlined on SS-OCTA, however, not reaching statistical significance (p = 0.094). Regarding 3 × 3-mm2 measurements, the median lesion sizes between the two OCTA devices were comparable (p = 0.492). Indocyanine green angiography depicted a larger lesion area than both OCTA devices, however, not reaching statistical significance. CONCLUSION: SD-OCTA tends to show smaller areas of MNV extension than SS-OCTA regarding 6 × 6 mm2 scans. The lesion size of MNV can be very well compared between the different devices, emphasizing the use of OCTA for monitoring neovascular area. Lesion measurements on SS-OCTA correlate better with ICGA than SD-OCTA.

Short-term outcomes of patients with neovascular exudative AMD: the effect of COVID-19 pandemic.

PURPOSE: To estimate the impact of delayed care during the coronavirus disease 2019 (COVID-19) pandemic on the outcomes of patients with neovascular age-related macular degeneration (AMD). METHODS: Consecutive patients with diagnosis of neovascular AMD were consecutively enrolled between March 9, 2020, and June 12, 2020, (during and immediately after the Italian COVID-19 quarantine). During the inclusion (or pandemic) visit (V0), patients received a complete ophthalmologic evaluation, including optical coherence tomography (OCT). Best-corrected visual acuity (BCVA) and OCT findings from the two preceding visits (V-1 and V-2) were compared with data at V0. RESULTS: One-hundred patients (112 eyes) were enrolled in this study. The time interval between following visits was 110.7 ± 37.5 days within V0 and V-1 and 80.8 ± 39.7 days within V-1 and V-2, respectively (P < 0.0001). BCVA was statistically worse at the V0 visit as compared with the immediately preceding (V-1) visit (0.50 ± 0.43 LogMAR and 0.45 ± 0.38 LogMAR at the V0 and V-1 visits, respectively; P = 0.046). On structural OCT, 91 out of 112 (81.2%) neovascular AMD eyes displayed the evidence of exudative disease activity at the V0 visit, while 77 (68.7%) eyes exhibited signs of exudation at the V-1 visit (P = 0.022). No differences in terms of BCVA and OCT findings were detected between the V-1 and V-2 visits. In multiple regression analysis, the difference in BCVA between V0 and V-1 visits was significantly associated with the interval time within these two visits (P = 0.026). CONCLUSION: The COVID-19 pandemic-related postponement in patient care proved to be significantly associated with worse short-term outcomes in these patients.

Retinal vascular development in an immature retina at 33-34 weeks postmenstrual age predicts retinopathy of prematurity.

In preterm birth, the immature retina can develop a potentially blinding disorder of the eye known as retinopathy of prematurity (ROP). The vaso-proliferative phase of ROP begins at an approximate postmenstrual age (PMA) of 32 weeks. There is little or no evidence of an association between ROP development and retinal status in the early vaso-proliferative phase. We aimed to evaluate the retinal vascular findings of infants at 33-34 weeks PMA to determine their risk of ROP. We reviewed 130 serial wide-field retinal images from 65 preterm infants born before the gestational age of 31 weeks. ROP occurred more frequently in infants having a leading vascular edge within posterior Zone II. This was in contrast to normal infants, who are characterized by complete retinal vascularization up to Zone II at 34 weeks PMA. The probability of ROP development in preterm infants with retinal edge hemorrhage was 24.58 times higher than in preterm infants without retinal edge hemorrhage. Eyes with ROP that required treatment showed significantly delayed retinal vascularization accompanied by pre-plus disease. In conclusion, retinal status in the early vaso-proliferation phase might determine the risk of ROP.

The process of revascularization in the neonatal mouse retina following short-term blockade of vascular endothelial growth factor receptors.

Misdirected vascular growth frequently occurs in the neovascular diseases in the retina. However, the mechanisms are still not fully understood. In the present study, we created capillary-free zones in the central and peripheral retinas in neonatal mice by pharmacological blockade of vascular endothelial growth factor (VEGF) signaling. Using this model, we investigated the process and mechanisms of revascularization in the central and peripheral avascular areas. After the completion of a 2-day treatment with the VEGF receptor tyrosine kinase inhibitor KRN633 on postnatal day (P) 4 and P5, revascularization started on P8 in the central avascular area where capillaries had been dropped out. The expression levels of VEGF were higher in the peripheral than in the central avascular area. However, the expansion of the vasculature in the peripheral avascular retina remained suppressed until revascularization had been completed in the central avascular area. Additionally, we found disorganized endothelial cell division, misdirected blood vessels with irregular diameters, and abnormal fibronectin networks at the border of the vascular front and the avascular retina. In the central avascular area, a slight amount of fibronectin as non-vascular component re-formed to provide a scaffold for revascularization. Mechanistic analysis revealed that higher levels of VEGF attenuated the migratory response of endothelial cells without decreasing the proliferative activity. These results suggest that the presence of concentration range of VEGF, which enhances both migration and proliferation of the endothelial cells, and the structurally normal fibronectin network contribute to determine the proper direction of angiogenesis.

Choriocapillaris Flow Deficits and Treatment-Naïve Macular Neovascularization Secondary to Age-Related Macular Degeneration.

Purpose: To evaluate choriocapillaris (CC) flow deficits (FD) in eyes with treatment-naïve macular neovascularization (MNV) and to compare CC FD around exudative versus nonexudative MNV. Methods: Treatment-naïve eyes with a diagnosis of either exudative or nonexudative AMD and type 1 MNV were included. Normal control eyes were age-matched to each AMD eye one to one. En face optical coherence tomography angiograms were analyzed for percentage of CC FD (FD%) in two concentric 500 µm rings, ring 1 and ring 2, surrounding the dark halo around MNV. The mean CC FD% in ring 1 and ring 2 was evaluated for each eye. A secondary analysis was similarly carried out to investigate the differences in CC FD% in exudative versus nonexudative treatment-naïve MNV. Results: Twenty-three eyes with treatment-naïve MNV were age matched with 23 normal controls. The mean CC FD% was significantly greater in both rings in the MNV versus the normal control group (P < 0.05) and was significantly greater in the inner ring, closer to the lesion, than the outer ring. The mean FD% was also greater in both rings in the exudative versus the nonexudative MNV group, but this difference did not reach statistical significance. Conclusions: The CC FD% was greater in the area surrounding MNV versus age-matched normal controls and in the ring closer to the MNV lesion. Further, CC FD was greater in eyes with exudative versus nonexudative MNV in both rings surrounding the associated dark halo, although this difference was not statistically significant.

Effect and mechanism of the long noncoding RNA MALAT1 on retinal neovascularization in retinopathy of prematurity.

AIMS: The most typical pathological manifestation of retinopathy of prematurity (ROP) is Retinal neovascularization (RNV). Long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been reported to mediate angiogenesis. Our experiment aimed to research the effect and mechanism of the MALAT1 on RNV in ROP. MAIN METHODS: C57 mice was used to establish oxygen-introduced retinopathy (OIR), and divided into control, hyperoxia, hyperoxia control siRNA, and hyperoxia MALAT1 siRNA groups. KEY FINDINGS: It was shown that MALAT1 mRNA was high expressed in the retinas of OIR mice. Further studies revealed that after intravitreal injection of MALAT1 siRNA, the degree of retinopathy was significantly reduced compared with OIR group. In addition, the protein and mRNA expression levels of CCN1, AKT and VEGF were significantly decreased. This was accompanied by a decrease in inflammatory genes including IL-1ß, IL-6, and TNF-α compared with the hyperoxia control siRNA mice. SIGNIFICANCE: The result suggested that MALAT1 may be involved in the process of RNV in ROP and MALAT1 siRNA may be a promising agent for the treatment of ROP by inhibiting RNV.

Association of Intravitreal Aflibercept With Optical Coherence Tomography Angiography Vessel Density in Patients With Proliferative Diabetic Retinopathy: A Secondary Analysis of a Randomized Clinical Trial.

Importance: Although previous studies have evaluated the association between anti-vascular endothelial growth factor therapy and macular vessel density, they were confounded by the presence of macular edema, which may be associated with artifacts and segmentation errors in optical coherence tomography angiography (OCTA). Objective: To evaluate the association of intravitreal aflibercept with changes in macular vascular density using OCTA in patients with proliferative diabetic retinopathy without diabetic macular edema. Design, Setting, and Participants: This post hoc analysis of a randomized clinical trial used data on 40 eyes of 40 patients with proliferative diabetic retinopathy without diabetic macular edema who were enrolled in the Intravitreal Aflibercept for Retinal Nonperfusion in Proliferative Diabetic Retinopathy (RECOVERY) clinical trial from August 1, 2016, to June 31, 2017. Three patients were lost to follow-up at month 12, and 5 patients were excluded from analysis because of poor OCTA image quality, leaving 16 patients in each cohort in the final analysis. Data analysis was performed from March 1, 2018, to January 15, 2019. Intervention: In the RECOVERY trial, patients were randomized into cohorts receiving 2 mg of aflibercept injections monthly (n = 20) or quarterly (n = 20) and treated for 12 months. Main Outcomes and Measures: The percentage of vascular density (in total scan and foveal and parafoveal regions) was compared before and after 12 months of therapy. Results: The sample for this OCTA analysis included 32 eyes from 32 patients (mean [SD] age, 48.37 [12.30] years; 17 [53.1%] male). The mean (SD) total scan vascular density for the superficial vascular complex was 42.28% (4.03%; 95% CI, 40.63%-43.93%) at baseline and 39.64% (4.01%; 95% CI, 37.91%-41.37%) at month 12 (P = .69). For the deep vascular complex, the mean (SD) vascular density was 48.42% (4.99%; 95% CI, 46.36%-50.47%) at baseline and 45.69% (4.63%; 95% CI, 43.69%-47.70%) at month 12 (P = .40). For the choriocapillaris, the mean (SD) vascular density was 64.42% (3.36%; 95% CI, 63.04%-65.81%) at baseline and 62.55% (4.79%; 95% CI, 60.48%-64.62%) at month 12 (P = .16). There was no difference in vascular density parameters between monthly and quarterly injection arms at month 12. Conclusions and Relevance: In this study, macular vascular density did not change after 12 months of intravitreal aflibercept therapy. Because nonperfusion is expected to progress in diabetic retinopathy, this finding may represent a beneficial association between anti-vascular endothelial growth factor therapy and macular vascular density. Trial Registration: ClinicalTrials.gov Identifier: NCT02863354.

Quantification of Retinal Nonperfusion and Neovascularization With Ultrawidefield Fluorescein Angiography in Patients With Diabetes and Associated Characteristics of Advanced Disease.

Importance: Quantification of nonperfusion (NP) and neovascularization (NV) in diabetic retinopathy (DR) may identify better biomarkers of disease progression. Objective: To identify demographic risk factors and markers of advanced DR that are associated with increased areas of NP and NV in eyes with disease ranging from no DR but diagnosed as having diabetes to proliferative DR (PDR) and to calculate a threshold total area of NP that may be associated with an increased risk of PDR. Design, Setting, and Participants: This retrospective case series was performed on ultrawidefield fluorescein angiography (UWF FA) images from January 2009 to May 2018 at the University of Michigan Kellogg Eye Center. A total of 363 participants (651 eyes) diagnosed as having type 1 or 2 diabetes receiving UWF FA were included. Exclusion criteria included previous panretinal photocoagulation (PRP) and poor-quality images (eg, vitreous hemorrhage and significant cataract). Main Outcomes and Measures: The surface areas in millimeters squared of the foveal avascular zone; total NP; NP at posterior pole, midperiphery, and far periphery; total NV; NV at posterior pole, midperiphery, and far periphery were measured. Results: Of 363 patients, most were male (205 patients [56.5%]) and white (247 [68%]) or black (77 [21.2%]). The mean (SD) age was 59.4 (13.7) years. Seventy-six eyes with no DR, 92 with mild NPDR, 144 with moderate NPDR, 101 with severe NPDR, 220 with PDR, and 18 with DR of unknown severity were included. Male sex had a positive association with total NP (difference, 15.72; 95% CI, 4.83-26.61; P = .005); black race/ethnicity with total NV (difference, 2.32; 95% CI, 0.09-4.55; P = .04); and vitreous hemorrhage with total NP (difference, 30.00; 95% CI, 5.26-54.75; P = .02). A threshold total NP area of 77.48 mm2 (95% CI, 54.24-92.66 mm2) was identified, at greater than which patients may have an increased risk of developing PDR (sensitivity of 59.5% and specificity of 73.6%). Conclusions and Relevance: Our results indicate NP and NV can be quantified on UWF FA. These biomarkers interpreted with demographic risk factors may help predict disease progression. Conclusions are limited by ascertainment and information biases because the results are from retrospective data.

Anti-angiogenic effect of EGHB010, a standardized herbal formula of Paeoniae radix and Glycyrrhizae radix.

EGHB010 is a standardized herbal formula of the rhizome mixture of Paeonia lactiflora Pallas and Glycyrrhiza uralensis Fisch. Neovascularization in the retina is a common pathophysiology of diabetic retinal microvasculopathy and exudative macular degeneration. In this study, we evaluated the inhibitory effects of EGHB010 on abnormal retinal angiogenesis in a hyperoxia-induced neovascular retinopathy model. Vascular endothelial growth factor (VEGF)-mediated vascular tube formation was assayed in human umbilical vascular endothelial cells (HUVECs). Experimental angiogenesis in the retinas was induced by exposing C57BL/6 pups to hyperoxic environment (75% oxygen) on postnatal day 7 (P7) and then returning them to normal oxygen pressure on P12. EGHB010 (50 and 100 mg/kg/day) was administered intraperitoneally for 5 days (P12 - P16). Retinal flat mounts were prepared to measure the extent of retinal neovascularization on P17. The incubation of HUVECs with EGHB010 (1-25 µg/mL) resulted in the inhibition of VEGF-mediated tube formation in a dose-dependent manner. EGHB010 at doses of 50 and 100 mg/kg/day inhibited the formation of retinal neovascular tufts by 31.15±2.28% and 59.83±2.92%, respectively. Together, our results indicate that EGHB010 is a potent anti-angiogenic agent and may have potential for the control of abnormal retinal vessel growth in patients with ischemic retinopathy.