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Purpose: To evaluate the utility of extended field swept-source Optical Coherence Tomography Angiography (SS-OCTA) imaging biomarkers in predicting the occurrence of clinically significant outcomes in eyes with Non-Proliferative Diabetic Retinopathy (NPDR)., Design: Retrospective clinical case-control study., Methods: Single-center clinical study. Eighty-eight eyes with NPDR from 57 participants (median age: 64.0 years; mean duration of diabetes: 15.8 years) with at least 2 consecutive SS-OCTA scans over a follow-up period of at least 6 months were included. The presence of intraretinal microvascular abnormalities (IRMAs) at baseline and the stability of IRMAs during follow-up period on 12 × 12-mm angiograms were evaluated. Baseline nonperfusion ischemia index (ISI) and other SS-OCTA metrics were calculated on FIJI and ARI Network. Significant clinical outcomes were defined as occurrence of one or more of the following events at the last available clinical visit:1. significant DR progression (2-step DR progression or progression to proliferative DR (PDR)); 2) development of new center-involving diabetic macular edema (CI-DME); and 3) initiation of treatment with PRP or anti-VEGF injections during the follow-up period. Mixed-effects Cox regression models was used to explore these outcomes., Results: Following a clinical follow-up period lasting 25.1 ± 10.8 months, we observed significant clinical outcomes in 17 eyes (19.3%). Among these, 7 eyes (8.0%) experienced significant progression and 4 eyes (4.5%) developed CI-DME. Anti-VEGF injections were initiated in 15 eyes (17.0%), while PRP was initiated in 2 eyes (2.3%). Upon adjusting for age, the duration of DM, and prior Anti-VEGF treatments, our analysis revealed that non-stable IRMAs during the follow-up periods and a higher ischemia index at baseline were significantly associated with the occurrence of significant clinical outcomes with HRs of 3.88 (95% CI: 1.56-9.64; p = .004) and 1.05 (95% CI: 1.02-1.09; p = .004), respectively., Conclusions: In conclusion, NPDR eyes with non-stable IRMAs over time and more ischemia at baseline are in higher risk of developing significant clinical outcomes. Our findings suggest that expanded field SS-OCTA may offer additional prognostic benefits for clinical DR staging and predicting high-risk patients., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: To investigate structure-function associations between contrast sensitivity (CS) and widefield swept-source optical coherence tomography angiography (WF SS-OCTA) vascular metrics across stages of non-proliferative (NPDR) and proliferative diabetic retinopathy (PDR), without diabetic macular oedema., Methods: Prospective cross-sectional study in 140 eyes of 99 patients: 33 mild NPDR, 24 moderate/severe NPDR, 15 PDR, 33 diabetic without DR (DMnoDR) and 46 control eyes. Mixed-effects multivariable regression models to evaluate associations between quantitative contrast sensitivity function (Adaptive Sensory Technology) and vessel density (VD) and vessel skeletonised density (VSD) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) on same-day imaging with WF SS-OCTA (Plex Elite 9000, Carl Zeiss Meditec)., Results: Standardised β coefficients for area under the logarithm of contrast sensitivity function curve (AULCSF) versus visual acuity (VA) at 3×3 mm scans: SCP VSD (β=0.32, p<0.001 vs -0.18, p=0.044), DCP VSD (β=0.30, p<0.001 vs -0.21, p=0.02), SCP VD (β=0.25, p=0.004 vs -0.13, p=0.129), DCP VD (β=0.26, p=0.003 vs -0.19, p=0.034). AULCSF was significantly reduced in mild NPDR (β=-0.28, p<0.001) and DMnoDR (β=-0.19, p=0.005) versus controls, while VA was not significantly different. AULCSF performed better than VA in differentiating between controls and DMnoDR (0.69 vs 0.50), controls and mild NPDR (0.76 vs 0.61) and controls and moderate/severe NPDR (0.89 vs 0.73)., Conclusions: DR-induced microvascular changes on OCTA are associated with larger changes on CS than in VA. CS is affected earlier than VA in the course of DR and performed better in discriminating between controls, DMnoDR and across DR stages., Competing Interests: Competing interests: No conflicting relationship exists for any author. FV, GB, RK, YC, IG, JYM and RZ—no disclosures. NAP is a consultant for Atheneum, Alcon, Allergan, Alimera, Eyepoint, Lifesciences, Guidepoint and GLG. DW holds a patent through Massachusetts Eye and Ear. DH is a consultant for Allergan, Genentech and Omeicos Therapeutics, and has received financial support from the National Eye Institute, Lions VisionGift, Commonwealth Grant, Lions International, Syneos and the Macular Society. JWM is a consultant for Heidelberg Engineering, Sunovion, KalVista Pharmaceuticals and ONL Therapeutics; holds a patent through and has received financial support from ONL, Valeant Pharmaceuticals/Massachusetts Eye and Ear; and has received financial support from Lowy Medical Research Institute. LK has received research support from the National Eye Institute and CureVac; and has a financial arrangement with Pykus Therapeutics. DV is a consultant for Valitor and Olix Pharmaceuticals; is a consultant for Valitor and Olix Pharmaceuticals; and has received financial support from the National Eye Institute and by grants from the National Institute of Health (R01EY025362 and R21EY0203079), Research to Prevent Blindness, Loefflers Family Foundation, Yeatts Family Foundation and Alcon Research Institute. JBM is a consultant for Alcon, Allergan, Carl Zeiss, Sunovion and Genentech., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To longitudinally investigate the changes in intraretinal microvascular abnormalities (IRMAs) over time, employing swept-source optical coherence tomography angiography in eyes with diabetic retinopathy., Methods: In this retrospective, longitudinal study, we evaluated 12 × 12-mm swept-source optical coherence tomography angiography centered on the macula at baseline and last available follow-up visit for (1) IRMA changes during follow-up, defined as (a) stable, (b) regressed, (c) obliterated, and (d) progressed; and the (2) development of new neovascularization (NV) and their origins. Competing-risk survival analysis was used to assess the factors associated with these changes., Results: In total, 195 eyes from 131 participants with diabetic retinopathy were included. Stable, regressed, obliterated, and progressed IRMA were observed in 65.1%, 12.8%, 11.3%, and 19% of eyes with diabetic retinopathy, respectively. Anti-VEGF injections during the follow-up periods and a slower increase of foveal avascular zone were associated with IRMA regression (P < 0.001 and P = 0.039). Obliterated IRMA were correlated with previous panretinal photocoagulation (P < 0.001) and a lower deep capillary plexus vessel density at baseline (P = 0.007), as well as with follow-up anti-VEGF injections (P = 0.025). A higher baseline ischemia index (ISI) and panretinal photocoagulation during the follow-up periods were associated with IRMA progression (P = 0.049 and P < 0.001). A faster increase in ISI predicted the development of NV elsewhere (NVE) from veins (P < 0.001). No significant factors were found to be associated with NVE originating from IRMA., Conclusions: Changes in IRMA closely correlated with the severity of retinal ischemia and treatment. Notably, our study confirmed the potential, yet relatively rare, development of NVE from IRMA in a large cohort; however, the risk factors associated with this transformation require further exploration.

Background/aims: We sought to evaluate widefield swept-source optical coherence tomography angiography (WF SS-OCTA) among eyes with concomitant age-related macular degeneration (AMD) and diabetes mellitus or diabetic retinopathy (DM/DR)., Methods: This cross-sectional, comparative study consisted of three study groups: eyes with (1) AMD and DM/DR, (2) AMD alone and (3) DM/DR alone. WF SS-OCTA (3×3, 6×6 and 12×12 mm) images were captured. Vascular metrics included foveal avascular zone (FAZ), vessel density (VD) and vessel skeletonised density (VSD). Mixed-effects multivariable regression models adjusted for age were performed by cohort and subgroup based on AMD and DR stages., Results: Our cohort included 287 eyes from 186 patients with an average age of 64±14.0 years old. Results revealed significantly reduced vascular metrics in concomitant AMD and DM/DR eyes (N=68) compared with AMD-only eyes (N=71) on all angiograms but not compared with DM/DR-only eyes (N=148). For example, when compared with AMD-only eyes, AMD and DM/DR eyes had significantly reduced VD (β=-0.03, p=0.016) and VSD (β=-1.09, p=0.022) on 12×12 mm angiograms, increased FAZ perimeter (β=0.51, p=0.025) and FAZ area (β=0.11, p=0.015) on 6×6 mm angiogram, and reductions in all VD and VSD metrics on 3×3 and 6×6 mm angiograms. However, only 3×3 mm angiogram FAZ metrics were significantly different when comparing DM/DR eyes with concomitant AMD and DM/DR eyes., Conclusion: WF SS-OCTA revealed significant reductions in retinal microvasculature metrics in AMD and DM/DR eyes compared with AMD-only eyes but not compared with DM/DR-only eyes., Competing Interests: Competing interests: JBM is a consultant for Alcon, Allergan, Carl Zeiss, Sunovion, Topcon and Genentech. DV is a consultant for Valitor and Olix Pharmaceuticals; and has received financial support from National Eye Institute and by grants from the National Institute of Health (R01EY025362 and R21EY0203079), Research to Prevent Blindness, Loefflers Family Foundation, Yeatts Family Foundation and Alcon Research Institute. DW holds a patent through Massachusetts Eye and Ear. JWM is a consultant for Sunovion, KalVista Pharmaceuticals and ONL Therapeutics; holds a patent through and has received financial support from ONL, Drusolv Therapeutics, Valeant Pharmaceuticals/Massachusetts Eye and Ear; has received financial support from Lowy Medical Research Institute; holds a position of influence with Apitnyx; and holds personal financial interest in Ciendias Bio. LK has received research support from National Eye Institute and CureVac; and has a financial arrangement with Pykus Therapeutics. NAP is a consultant for Alimera Sciences, Alcon, Allergan and Genentech. DH is a consultant for Allergen, Genentech and Omeicos Therapeutics; and has received financial support from National Eye Institute, Lions VisionGift, Commonwealth Grant, Lions International, Syneos and the Macular Society. The following authors do not have any competing interests to disclose—MF, GB, IG, HEW, TK, FV, RZ, HC and DS., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To explore the association between widefield swept-source optical coherence tomography angiography (WF SS-OCTA) metrics, including nonperfusion area (NPA) and neovascularization (NV), and presence of neovascular glaucoma (NVG) in patients with proliferative diabetic retinopathy (PDR)., Methods: A prospective, cross-sectional study was conducted from November 2018 to February 2020. A total of 85 eyes of 60 PDR patients without NVG and 9 eyes of 8 PDR patients with NVG were included. Retinal ischemic parameters (NPA; ischemia index [NPA/total retinal area]) and NV features (NV number; NV area; NV vessel density) were evaluated. Foveal avascular zone (FAZ), macular thickness/volume, and choroidal thickness/volume were obtained using the Zeiss ARI Network. WF SS-OCTA retinal and choroidal metrics, systemic, and ocular parameters were screened using Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression for variable selection. Firth's bias-reduced logistic regression (outcome: presence of NVG) was subsequently used to identify parameters associated with NVG., Results: After LASSO variable selection, 8 variables were significantly associated with the presence of NVG: DM duration (years), insulin (yes/no), best-corrected visual acuity (BCVA) (logMAR), IOP, ischemia index, skeletonized vessel density, macular thickness (inner inferior, outer temporal regions). Firth's bias-reduced logistic regression showed ischemia index (odds ratio [OR]=13.2, 95% confidence interval [CI]:5.3-30.7, P<0.001) and BCVA (OR=5.8, 95%CI:1.2-28.8, P<0.05) were associated with the presence of NVG. NV metrics, FAZ, and choroidal parameters were not related to NVG., Conclusions: Retinal ischemia but not NV was associated with the presence of NVG in patients with PDR using WF SS-OCTA. Larger, longitudinal studies are needed to validate imaging biomarkers associated with diabetic NVG., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: To investigate the prevalence and clinical characteristics of diabetic patients with retinal venous loops (RVLs) and to assess the association with retinal ischemia using widefield swept-source optical coherence tomography angiography (WF SS-OCTA)., Methods: In this retrospective, cross-sectional study, a total of 195 eyes of 132 diabetic patients (31 eyes with no diabetic retinopathy (DR), 76 eyes with nonproliferative DR (NPDR), and 88 eyes with proliferative DR (PDR)) were imaged with WF SS-OCTA using Angio 6 × 6 mm and Montage 15 × 15 mm scans. Quantitative ischemia-related parameters, including ischemia index (ratio of nonperfusion area to total retinal area), foveal avascular zone (FAZ), and neovascularization features, were evaluated. RVLs were classified as type I or type II according to the branching level of the feeder vessel. A multivariate generalized estimating equations (GEE) logistic regression model was used to analyze the association of systemic parameters and ischemia-related metrics with RVLs in PDR eyes., Results: Forty-eight RVLs were identified in 22 eyes (11.28%). The prevalence of RVLs was higher in PDR compared to NPDR eyes (21.59% vs. 3.95%, P < 0.05). Type II RVLs accounted for a higher proportion than type I (89.58% vs. 10.42%, P < 0.001). RVLs were more likely to originate from superior (vs. inferior) and temporal (vs. nasal) veins (P < 0.05). The GEE model showed that neovascularization (NV) flow area and diastolic blood pressure were associated with RVLs in the PDR group (P < 0.05)., Conclusion: WF SS-OCTA is useful for the identification of RVLs in patients with DR. NV flow area and diastolic blood pressure were associated with the presence of RVLs in eyes with PDR. Ischemia index, FAZ, and other WF SS-OCTA parameters were not associated with RVLs. Further longitudinal studies are needed to identify the role of RVLs in DR progression., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aims: To compare the efficacy of diabetic retinal neovascularisation (NV) detection using the widefield swept-source optical coherence tomography angiography (WF SS-OCTA) vitreoretinal interface (VRI) Angio slab and SS-OCT VRI Structure slab., Methods: A prospective, observational study was performed at Massachusetts Eye and Ear from January 2019 to June 2020. Patients with proliferative diabetic retinopathy (PDR), patients with non-proliferative diabetic retinopathy and patients with diabetes but without diabetic retinopathy were included. All patients were imaged with WF SS-OCTA using the 12×12 mm Angio scan protocol centred on the fovea and optic disc. The en-face SS-OCTA VRI Angio slab and SS-OCT VRI Structure slab were evaluated for the presence or absence of NV. SS-OCTA B-scan was used to classify NV according to cross-sectional morphology (forward, tabletop or flat). All statistical analyses were performed using SPSS V.26.0., Results: One hundred and forty-two eyes of 89 participants were included in the study. VRI Angio detected NV at higher rates compared with VRI Structure (p<0.05). Combining VRI Angio and Structure improved detection rates compared with VRI Angio alone (p<0.05). Due to segmentation errors of the internal limiting membrane, NV with flat morphological classification had lower rates of detection on VRI Angio compared with NV with forward and tabletop morphology (p<0.05)., Conclusions: WF SS-OCTA 12×12 mm VRI Angio and SS-OCT VRI Structure imaging centred on the fovea and optic disc detected NV with high sensitivity and low false positives. The VRI slab may be useful to diagnose and monitor PDR in clinical practice., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To investigate the association among widefield swept-source (SS) OCT angiography (OCTA) metrics and systemic parameters and vitreous hemorrhage (VH) occurrence in eyes with proliferative diabetic retinopathy (PDR)., Design: Prospective, observational study., Participants: Fifty-five eyes from 45 adults with PDR, with no history of VH, followed up for at least 3 months., Methods: All patients underwent widefield SS OCTA (Montage 15 × 15 mm and high-definition (HD)-51 line scan) imaging. Images were evaluated independently by 2 graders for quantitative and qualitative widefield SS OCTA metrics defined a priori. Systemic and ocular parameters and widefield SS OCTA metrics were screened using least absolute shrinkage and selection operator and logistic or Cox regression for variable selection. Firth's bias-reduced logistic regression models (outcome, occurrence of VH) and Cox regression models (outcome, time to occurrence of VH) were used to identify parameters associated with VH occurrence., Main Outcome Measures: Occurrence of VH., Results: Over a median follow-up of 363 days (range, 28-710 days), 13 of 55 PDR eyes (24%) demonstrated VH during the follow-up period. Presence of extensive neovascularizations (odds ratio, 8.05; 95% confidence interval [CI], 1.43-58.56; P = 0.02), defined as neovascularizations with total area of more than 4 disc diameters, and forward neovascularizations (odds ratio, 5.42; 95% CI, 1.26-35.16; P = 0.02) that traversed the posterior hyaloid face into the vitreous were associated with the occurrence of VH. The presence of flat neovascularizations (odds ratio, 0.25; 95% CI, 0.04-1.01; P = 0.05) confined to the posterior hyaloid face was associated with a lower risk of VH with borderline significance. Similarly, presence of extensive neovascularizations (hazard ratio, 18.24; 95% CI, 3.51-119.47; P < 0.001) and forward neovascularizations (hazard ratio, 9.60; 95% CI, 2.07-68.08; P = 0.002) was associated significantly with time to development of VH., Conclusions: Widefield SS OCTA is useful for evaluating neovascularizations and their relationship with the vitreous. The presence of forward and extensive neovascularizations was associated with the occurrence of VH in patients with PDR. Larger samples and longer follow-up are needed to verify the risk factors and imaging biomarkers for diabetic VH., (Copyright © 2021 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Retinal imaging remains the mainstay for monitoring and grading diabetic retinopathy. The gold standard for detecting proliferative diabetic retinopathy (PDR) requiring treatment has long been the seven-field stereoscopic fundus photography and fluorescein angiography. In the past decade, ultra-wide field fluorescein angiography (UWF-FA) has become more commonly used in clinical practice for the evaluation of more advanced diabetic retinopathy. Since its invention, optical coherence tomography (OCT) has been an important tool for the assessment of diabetic macular edema; however, OCT offered little in the assessment of neovascular changes associated with PDR until OCT-A became available. More recently, swept source OCT allowed larger field of view scans to assess a variety of DR lesions with wide field swept source optical coherence tomography (WF-SS-OCTA). This paper reviews the role of WF-SS-OCTA in detecting neovascularization of the disc (NVD), and elsewhere (NVE), microaneurysms, changes of the foveal avascular zone (FAZ), intraretinal microvascular abnormalities (IRMA), and capillary non-perfusion, as well as limitations of this evolving technology.

Aims: To compare widefield swept-source optical coherence tomography angiography (WF SS-OCTA) with ultra-widefield colour fundus photography (UWF CFP) and fluorescein angiography (UWF FA) for detecting diabetic retinopathy (DR) lesions., Methods: This prospective, observational study was conducted at Massachusetts Eye and Ear from December 2018 to October 2019. Proliferative DR, non-proliferative DR and diabetic patients with no DR were included. All patients were imaged with a WF SS-OCTA using a Montage 15×15 mm scan. UWF CFP and UWF FA were taken by a 200°, single capture retinal imaging system. Images were independently evaluated for the presence or absence of DR lesions including microaneurysms (MAs), intraretinal microvascular abnormalities (IRMAs), neovascularisation elsewhere (NVE), neovascularisation of the optic disc (NVD) and non-perfusion areas (NPAs). All statistical analyses were performed using SPSS V.25.0., Results: One hundred and fifty-two eyes of 101 participants were included in the study. When compared with UWF CFP, WF SS-OCTA was found to be superior in detecting IRMAs (p<0.001) and NVE/NVD (p=0.007). The detection rates of MAs, IRMAs, NVE/NVD and NPAs in WF SS-OCTA were comparable with UWF FA images (p>0.05). Furthermore, when we compared WF SS-OCTA plus UWF CFP with UWF FA, the detection rates of MAs, IRMAs, NVE/NVD and NPAs were identical (p>0.005). Agreement (κ=0.916) between OCTA and FA in classifying DR was excellent., Conclusion: WF SS-OCTA is useful for identification of DR lesions. WF SS-OCTA plus UWF CFP may offer a less invasive alternative to FA for DR diagnosis., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To compare different scan protocols of wide-field swept-source optical coherence tomography angiography (SS-OCTA) for the detection of diabetic retinopathy (DR) lesions., Design: Comparison of diagnostic approaches., Methods: A prospective, observational study was conducted at Massachusetts Eye and Ear from December 2018 to July 2019. Proliferative diabetic retinopathy (PDR), nonproliferative diabetic retinopathy (NPDR), and diabetic patients without DR were included. All patients were imaged using SS-OCTA using the following scan protocol: 3- × 3-mm Angio centered on the fovea; 6- × 6-mm Angio centered on the fovea and the optic disc; 15- × 9-mm Montage; and 12- × 12-mm Angio centered on the fovea and the optic disc. Images were independently evaluated by 2 graders for the presence or absence of DR lesions including microaneurysms, intraretinal microvascular abnormalities, neovascularization, nonperfusion areas, venous looping, and hard exudates. All statistical analyses were performed using commercial software., Results: A total of 176 eyes in 119 participants were included in the study. The detection rate of neovascularization on 6- × 6-mm Angio centered on the fovea was approximately one-half that on 15- × 9-mm Montage (P < .05) imaging. Combining 6- × 6-mm Angio imaging centered on the fovea and the optic disc could increase the rate to approximately two-thirds (P < .05). The 12- × 12-mm Angio imaging centered on the combination of fovea and optic disc had detection rates comparable to those of 15- × 9-mm Montage imaging for all DR lesions (P > .05). For microaneurysms, 6- × 6-mm Angio had better performance than 15- × 9-mm Montage (P < .05)., Conclusions: Wide-field SS-OCTA images were useful in detecting DR lesions. The 12- × 12-mm Angio imaging centered on the fovea and on the optic disc may be an optimal balance between speed and efficacy for evaluation of DR in clinical practice., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: To compare the choroidal thickness (CT) of diabetic eyes (different stages of disease) with controls, using swept-source optical coherence tomography., Methods: A multicenter, prospective, cross-sectional study of diabetic and nondiabetic subjects using swept-source optical coherence tomography imaging. Choroidal thickness maps, according to the nine Early Treatment Diabetic Retinopathy Study (ETDRS) subfields, were obtained using automated software. Mean CT was calculated as the mean value within the ETDRS grid, and central CT as the mean in the central 1 mm. Diabetic eyes were divided into four groups: no diabetic retinopathy (No DR), nonproliferative DR (NPDR), NPDR with diabetic macular edema (NPDR + DME), and proliferative DR (PDR). Multilevel mixed linear models were performed for analyses., Results: The authors included 50 control and 160 diabetic eyes (n = 27 No DR, n = 51 NPDR, n = 61 NPDR + DME, and n = 21 PDR). Mean CT (ß = -42.9, P = 0.022) and central CT (ß = -50.2, P = 0.013) were statistically significantly thinner in PDR eyes compared with controls, even after adjusting for confounding factors. Controlling for age, DR eyes presented a significantly decreased central CT than diabetic eyes without retinopathy (β = -36.2, P = 0.009)., Conclusion: Swept-source optical coherence tomography demonstrates a significant reduction of CT in PDR compared with controls. In the foveal region, the choroid appears to be thinner in DR eyes than in diabetic eyes without retinopathy.

Purpose: To compare choroidal vascular density (CVD) and volume (CVV) in diabetic eyes and controls, using en face swept-source optical coherence tomography (SS-OCT)., Design: Prospective cross-sectional study., Methods: Setting: Multicenter., Patient Population: Total of 143 diabetic eyes-27 with no diabetic retinopathy (DR), 47 with nonproliferative DR (NPDR), 51 with NPDR and diabetic macular edema (DME), and 18 with proliferative DR (PDR)-and 64 age-matched nondiabetic control eyes., Observation Procedures: Complete ophthalmologic examination and SS-OCT imaging. En face SS-OCT images of the choroidal vasculature were binarized., Main Outcome Measures: CVD, calculated as the percent area occupied by choroidal vessels in the central macular region (6-mm-diameter circle centered on the fovea), and throughout the posterior pole (12 × 9 mm). The central macular CVV was calculated by multiplying the average CVD by macular area and choroidal thickness (obtained with SS-OCT automated software). Multilevel mixed linear models were performed for analyses., Results: Compared to controls (0.31 ± 0.07), central macular CVD was significantly decreased by 9% in eyes with NPDR + DME (0.28 ± 0.06; ß = -0.03, P = .02) and by 15% in PDR (0.26 ± 0.05; ß = -0.04, P = .01). The central macular CVV was significantly decreased by 19% in eyes with PDR (0.020 ± 0.005 mm 3 , ß = -0.01, P = .01) compared to controls (0.025 ± 0.01 mm 3 )., Conclusions: Choroidal vascular density and volume are significantly reduced in more advanced stages of diabetic retinopathy. New imaging modalities should allow further exploration of the contributions of choroidal vessel disease to diabetic eye disease pathogenesis, prognosis, and treatment response., (Copyright © 2017. Published by Elsevier Inc.)

Purpose: To explore the association between widefield swept-source optical coherence tomography angiography (WF SS-OCTA) metrics, including nonperfusion area (NPA) and neovascularization (NV), and presence of neovascular glaucoma (NVG) in patients with proliferative diabetic retinopathy (PDR). Methods: A prospective, cross-sectional study was conducted from November 2018 to February 2020. A total of 85 eyes of 60 PDR patients without NVG and 9 eyes of 8 PDR patients with NVG were included. Retinal ischemic parameters (NPA; ischemia index [NPA/total retinal area]) and NV features (NV number; NV area; NV vessel density) were evaluated. Foveal avascular zone (FAZ), macular thickness/volume, and choroidal thickness/volume were obtained using the Zeiss ARI Network. WF SS-OCTA retinal and choroidal metrics, systemic, and ocular parameters were screened using Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression for variable selection. Firth's bias-reduced logistic regression (outcome: presence of NVG) was subsequently used to identify parameters associated with NVG. Results: After LASSO variable selection, 8 variables were significantly associated with the presence of NVG: DM duration (years), insulin (yes/no), best-corrected visual acuity (BCVA) (logMAR), IOP, ischemia index, skeletonized vessel density, macular thickness (inner inferior, outer temporal regions). Firth's bias-reduced logistic regression showed ischemia index (odds ratio [OR]=13.2, 95% confidence interval [CI]:5.3–30.7, P<0.001) and BCVA (OR=5.8, 95%CI:1.2–28.8, P<0.05) were associated with the presence of NVG. NV metrics, FAZ, and choroidal parameters were not related to NVG. Conclusions: Retinal ischemia but not NV was associated with the presence of NVG in patients with PDR using WF SS-OCTA. Larger, longitudinal studies are needed to validate imaging biomarkers associated with diabetic NVG. [ABSTRACT FROM AUTHOR]

Purpose : To investigate the prevalence and clinical characteristics of diabetic patients with retinal venous loops (RVLs) and to assess the association with retinal ischemia using widefield swept-source optical coherence tomography angiography (WF SS-OCTA). Methods: In this retrospective, cross-sectional study, a total of 195 eyes of 132 diabetic patients (31 eyes with no diabetic retinopathy (DR), 76 eyes with nonproliferative DR (NPDR), and 88 eyes with proliferative DR (PDR)) were imaged with WF SS-OCTA using Angio 6 × 6 mm and Montage 15 × 15 mm scans. Quantitative ischemia-related parameters, including ischemia index (ratio of nonperfusion area to total retinal area), foveal avascular zone (FAZ), and neovascularization features, were evaluated. RVLs were classified as type I or type II according to the branching level of the feeder vessel. A multivariate generalized estimating equations (GEE) logistic regression model was used to analyze the association of systemic parameters and ischemia-related metrics with RVLs in PDR eyes. Results: Forty-eight RVLs were identified in 22 eyes (11.28%). The prevalence of RVLs was higher in PDR compared to NPDR eyes (21.59% vs. 3.95%, P < 0.05). Type II RVLs accounted for a higher proportion than type I (89.58% vs. 10.42%, P < 0.001). RVLs were more likely to originate from superior (vs. inferior) and temporal (vs. nasal) veins (P < 0.05). The GEE model showed that neovascularization (NV) flow area and diastolic blood pressure were associated with RVLs in the PDR group (P < 0.05). Conclusion: WF SS-OCTA is useful for the identification of RVLs in patients with DR. NV flow area and diastolic blood pressure were associated with the presence of RVLs in eyes with PDR. Ischemia index, FAZ, and other WF SS-OCTA parameters were not associated with RVLs. Further longitudinal studies are needed to identify the role of RVLs in DR progression. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the short- and long-term impact of COVID-19—related lockdown on the vision of patients requiring intravitreal injections (IVI) for neovascular Age-related Macular degeneration (nvAMD), diabetic retinopathy (DR), central retinal vein occlusion (CRVO), or branch retinal vein occlusion (BRVO). Methods: This is a retrospective study from the Retina department of three Mass Eye and Ear centers. Charts of patients age of ≥ 18 years with any of the abovementioned diagnoses who had a scheduled appointment anytime between 17 March 2020 until 18 May 2020 (lockdown period in Boston, Massachusetts) were reviewed at baseline (up to 12 weeks before the lockdown), at first available follow-up (=actual f/u) during or after the lockdown period, at 3 months, 6 months, and at last available completed appointment of 2020. Results: A total of 1001 patients met the inclusion criteria. Of those patients, 479 (47.9%) completed their intended f/u appointment, while 522 missed it (canceled and "no show"). The delay in care of those who missed it was 59.15 days [standard deviation (SD) ± 49.6]. In these patients, significant loss of vision was noted at actual f/u [Best corrected visual acuity (BCVA) in LogMAR (Logarithm of the Minimum Angle of Resolution)—mean (±SD)—completed: 0.45 (±0.46), missed: 0.53 (±0.55); p = 0.01], which was more prominent in the DR group [Visual acuity (VA) change in LogMAR—mean (±SD); completed: 0.04 (±0.28), missed: 0.18 (±0.44); p = 0.02] and CRVO [completed: −0.06 (±0.27), missed: 0.11 (±0.35); p = <0.001] groups followed by nvAMD [completed: 0.006 (±0.16), missed: 0.06 (±0.27); p = 0.004] and BRVO [completed: −0.02 (±0.1), missed: 0.03 (±0.14); p = 0.02] ones. Overall, a higher percent of people who missed their intended f/u experienced vision loss of more than 15 letters at last f/u compared to those who completed it [missed vs. completed; 13.4% vs. 7.4% in nvAMD (p = 0.72), 7.8% vs. 6.3% in DR (0.84), 15.5% vs. 9.9% in CRVO (p < 0.001) and 9.6% vs. 2% in BRVO (p = 0.48)]. Conclusions: Delay in care of about 8.45 weeks can lead to loss of vision in patients who receive IVI with DR and CRVO patients being more vulnerable in the short-term, whereas in the long-term, CRVO patients followed by the nvAMD patients demonstrating the least vision recovery. BRVO patients were less likely to be affected by the delay in care. Adherence to treatment is key for maintaining and improving visual outcomes in patients who require IVI. [ABSTRACT FROM AUTHOR]

Optical coherence tomography angiography (OCT-A) has enabled fast, non-invasive, high-resolution visualization of vasculature within the eye. In the past few years, it has become increasingly utilized for a range of disorders including age-related macular degeneration, diabetic retinopathy, retinal vein occlusions, and uveitis among others. This article reviews technical aspects of OCT-A, its applications in chorioretinal disease, and known limitations of the technology. [ABSTRACT FROM AUTHOR]

Purpose: To assess the prevalence of foveal neovascularization (FNV) and its associated clinical features in proliferative diabetic retinopathy (PDR) eyes.Cross-sectional observational study. Participants underwent ultra-widefield photography, optical coherence tomography (OCT), and swept-source OCT angiography (SS-OCTA). FNV was defined as a hyperreflective lesion breaching the internal limiting membrane and displaying flow signal on OCTA, within 1-mm of foveal avascular zone. Vascular metrics were obtained from the ARI Network portal. Ischemic index (ISI) and inner choroid flow deficit percentage were calculated using FIJI from 12 × 12 and 6 × 6-mm scans, respectively. Logistic regression models were used to compare eyes with and without FNV.We included 249 eyes of 164 patients (age: 58 [50–65] years). FNV was identified in 20 eyes (8%). Univariate logistic regression revealed significant associations between FNV and younger age (p = 0.03), higher maximal HbA1c (p = 0.04), worse visual acuity (VA) (p = 0.01), presence of disorganization of retinal inner layers (DRIL) (p = 0.01), no macular posterior vitreous detachment (PVD) (p = 0.03), neovascularization elsewhere (NVE) and at the disc (NVD) (p = 0.01 and p = 0.001), and greater ISI (p = 0.04). In multivariable analysis, a significant association remained between FNV and worse VA (p = 0.04), NVD (p < 0.001), DRIL (p < 0.001), and absence of macular PVD (p = 0.01). No associations were found with SS-OCTA vascular metrics.This study provides a comprehensive characterization of FNV in PDR. FNV was identified in 8% of our cohort, being more prevalent in younger patients with severe PDR, as evidenced by NVD and DRIL presence. The absence of macular PVD may explain its association with younger age.What is known• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.What is new• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.Methods: To assess the prevalence of foveal neovascularization (FNV) and its associated clinical features in proliferative diabetic retinopathy (PDR) eyes.Cross-sectional observational study. Participants underwent ultra-widefield photography, optical coherence tomography (OCT), and swept-source OCT angiography (SS-OCTA). FNV was defined as a hyperreflective lesion breaching the internal limiting membrane and displaying flow signal on OCTA, within 1-mm of foveal avascular zone. Vascular metrics were obtained from the ARI Network portal. Ischemic index (ISI) and inner choroid flow deficit percentage were calculated using FIJI from 12 × 12 and 6 × 6-mm scans, respectively. Logistic regression models were used to compare eyes with and without FNV.We included 249 eyes of 164 patients (age: 58 [50–65] years). FNV was identified in 20 eyes (8%). Univariate logistic regression revealed significant associations between FNV and younger age (p = 0.03), higher maximal HbA1c (p = 0.04), worse visual acuity (VA) (p = 0.01), presence of disorganization of retinal inner layers (DRIL) (p = 0.01), no macular posterior vitreous detachment (PVD) (p = 0.03), neovascularization elsewhere (NVE) and at the disc (NVD) (p = 0.01 and p = 0.001), and greater ISI (p = 0.04). In multivariable analysis, a significant association remained between FNV and worse VA (p = 0.04), NVD (p < 0.001), DRIL (p < 0.001), and absence of macular PVD (p = 0.01). No associations were found with SS-OCTA vascular metrics.This study provides a comprehensive characterization of FNV in PDR. FNV was identified in 8% of our cohort, being more prevalent in younger patients with severe PDR, as evidenced by NVD and DRIL presence. The absence of macular PVD may explain its association with younger age.What is known• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.What is new• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.Results: To assess the prevalence of foveal neovascularization (FNV) and its associated clinical features in proliferative diabetic retinopathy (PDR) eyes.Cross-sectional observational study. Participants underwent ultra-widefield photography, optical coherence tomography (OCT), and swept-source OCT angiography (SS-OCTA). FNV was defined as a hyperreflective lesion breaching the internal limiting membrane and displaying flow signal on OCTA, within 1-mm of foveal avascular zone. Vascular metrics were obtained from the ARI Network portal. Ischemic index (ISI) and inner choroid flow deficit percentage were calculated using FIJI from 12 × 12 and 6 × 6-mm scans, respectively. Logistic regression models were used to compare eyes with and without FNV.We included 249 eyes of 164 patients (age: 58 [50–65] years). FNV was identified in 20 eyes (8%). Univariate logistic regression revealed significant associations between FNV and younger age (p = 0.03), higher maximal HbA1c (p = 0.04), worse visual acuity (VA) (p = 0.01), presence of disorganization of retinal inner layers (DRIL) (p = 0.01), no macular posterior vitreous detachment (PVD) (p = 0.03), neovascularization elsewhere (NVE) and at the disc (NVD) (p = 0.01 and p = 0.001), and greater ISI (p = 0.04). In multivariable analysis, a significant association remained between FNV and worse VA (p = 0.04), NVD (p < 0.001), DRIL (p < 0.001), and absence of macular PVD (p = 0.01). No associations were found with SS-OCTA vascular metrics.This study provides a comprehensive characterization of FNV in PDR. FNV was identified in 8% of our cohort, being more prevalent in younger patients with severe PDR, as evidenced by NVD and DRIL presence. The absence of macular PVD may explain its association with younger age.What is known• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.What is new• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.Conclusions: To assess the prevalence of foveal neovascularization (FNV) and its associated clinical features in proliferative diabetic retinopathy (PDR) eyes.Cross-sectional observational study. Participants underwent ultra-widefield photography, optical coherence tomography (OCT), and swept-source OCT angiography (SS-OCTA). FNV was defined as a hyperreflective lesion breaching the internal limiting membrane and displaying flow signal on OCTA, within 1-mm of foveal avascular zone. Vascular metrics were obtained from the ARI Network portal. Ischemic index (ISI) and inner choroid flow deficit percentage were calculated using FIJI from 12 × 12 and 6 × 6-mm scans, respectively. Logistic regression models were used to compare eyes with and without FNV.We included 249 eyes of 164 patients (age: 58 [50–65] years). FNV was identified in 20 eyes (8%). Univariate logistic regression revealed significant associations between FNV and younger age (p = 0.03), higher maximal HbA1c (p = 0.04), worse visual acuity (VA) (p = 0.01), presence of disorganization of retinal inner layers (DRIL) (p = 0.01), no macular posterior vitreous detachment (PVD) (p = 0.03), neovascularization elsewhere (NVE) and at the disc (NVD) (p = 0.01 and p = 0.001), and greater ISI (p = 0.04). In multivariable analysis, a significant association remained between FNV and worse VA (p = 0.04), NVD (p < 0.001), DRIL (p < 0.001), and absence of macular PVD (p = 0.01). No associations were found with SS-OCTA vascular metrics.This study provides a comprehensive characterization of FNV in PDR. FNV was identified in 8% of our cohort, being more prevalent in younger patients with severe PDR, as evidenced by NVD and DRIL presence. The absence of macular PVD may explain its association with younger age.What is known• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.What is new• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.Key messages: To assess the prevalence of foveal neovascularization (FNV) and its associated clinical features in proliferative diabetic retinopathy (PDR) eyes.Cross-sectional observational study. Participants underwent ultra-widefield photography, optical coherence tomography (OCT), and swept-source OCT angiography (SS-OCTA). FNV was defined as a hyperreflective lesion breaching the internal limiting membrane and displaying flow signal on OCTA, within 1-mm of foveal avascular zone. Vascular metrics were obtained from the ARI Network portal. Ischemic index (ISI) and inner choroid flow deficit percentage were calculated using FIJI from 12 × 12 and 6 × 6-mm scans, respectively. Logistic regression models were used to compare eyes with and without FNV.We included 249 eyes of 164 patients (age: 58 [50–65] years). FNV was identified in 20 eyes (8%). Univariate logistic regression revealed significant associations between FNV and younger age (p = 0.03), higher maximal HbA1c (p = 0.04), worse visual acuity (VA) (p = 0.01), presence of disorganization of retinal inner layers (DRIL) (p = 0.01), no macular posterior vitreous detachment (PVD) (p = 0.03), neovascularization elsewhere (NVE) and at the disc (NVD) (p = 0.01 and p = 0.001), and greater ISI (p = 0.04). In multivariable analysis, a significant association remained between FNV and worse VA (p = 0.04), NVD (p < 0.001), DRIL (p < 0.001), and absence of macular PVD (p = 0.01). No associations were found with SS-OCTA vascular metrics.This study provides a comprehensive characterization of FNV in PDR. FNV was identified in 8% of our cohort, being more prevalent in younger patients with severe PDR, as evidenced by NVD and DRIL presence. The absence of macular PVD may explain its association with younger age.What is known• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.• Neovascularization at the fovea occurs rarely in proliferative diabetic retinopathy.• OCT and OCT-angiography can be used to evaluate foveal neovascularization, which may be associated with choroidal vascular abnormalities.What is new• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study.• Foveal neovascularization was seen in 8% of eyes with proliferative diabetic retinopathy in this cohort.• Risk factors for foveal neovascularization included younger age, absence of macular posterior vitreous detachment, presence of neovascularization of the disc, and presence of disorganization of retinal inner layers.• We did not identify an association between foveal neovascularization and choroidal perfusion abnormalities in this study. [ABSTRACT FROM AUTHOR]