Relationship between macular perfusion and lesion distribution in diabetic retinopathy.

BACKGROUND/OBJECTIVES: To assess the relationship between macular vessel density metrics and foveal avascular zone (FAZ) characteristics on optical coherence tomography angiography (OCTA) and lesion distribution in eyes with diabetic retinopathy (DR). SUBJECTS/METHODS: Patients with DR who underwent both Optos ultrawidefield (UWF) pseudocolor imaging and macular OCTA (Cirrus Angioplex, 6 × 6 mm) were included in this cross-sectional observational study. The distribution of DR lesions was assessed by comparing each of the peripheral ETDRS extended fields (3-7) against their corresponding ETDRS field, hence eyes were defined as either having predominantly peripheral lesions (PPL) or predominantly central lesions (PCL). En face OCTA images from the superficial and deep capillary plexuses (SCP and DCP) were then analysed using Image J software. Perfusion density (PD), vessel length density (VLD), and fractal dimensions (FD) were calculated following binarization and skeletonization of the images. RESULTS: Out of 344 eyes, 116 (33.72%) eyes had PPL and 228 (66.28%) eyes had PCL. For all DRSS levels, VLD, PD, and FD were not significantly different between eyes with PPL and PCL. The FAZ in eyes with PPL, however, was found to be more circular in shape compared to eyes with PCL (p = 0.037). CONCLUSION: Although the presence of PPL has been associated with a higher risk for diabetic retinopathy progression, the macular perfusion is similar in eyes with PPL and PCL. The FAZ is more circular in eyes with PPL, but the clinical relevance of this difference remains to be defined.

Subretinal hyperreflective material in regions of atrophy and fibrosis in eyes with neovascular age-related macular degeneration.

BACKGROUND: Subretinal hyperreflective material (SHRM) is a significant biomarker for poor visual outcomes in neovascular age-related macular degeneration (nAMD); however, its relationship with fibrosis and atrophy is not well understood. This study aims to evaluate the relationship between SHRM, atrophy, and fibrosis in eyes receiving antivascular endothelial growth factor therapy for nAMD. METHODS: Post-hoc analysis of the 65 patients enrolled in the SEVEN-UP study, a multicenter cross-sectional study of patients originally enrolled in the ANCHOR and MARINA trials of ranibizumab. Color fundus photographs (CFP) were reviewed and manually segmented to define regions of atrophy and fibrosis. SHRM borders on OCT volume scans were manually delineated, and thickness measurements were computed and compared in corresponding regions of atrophy and fibrosis on the CFPs. RESULTS: Of the 65 subjects, 51 eyes showed atrophy and/or fibrosis on CFP and were included in the final analysis. Both atrophy and fibrosis regions exhibited SHRM on OCT. The mean SHRM thickness on OCT was significantly greater in CFP-fibrosis regions (44.19 ± 46.95 µm) compared with CFP-atrophy regions (14.28 ± 13.35 µm; p < 0.001). Additionally, the average maximum height of SHRM in fibrotic regions (268.04 ± 130.05 µm) was significantly thicker than in atrophic regions (121.95 ± 51.17 µm; p < 0.001). CONCLUSIONS: Although atrophy and fibrosis are thought to be different end-stage outcomes in eyes with nAMD, they both demonstrate SHRM on OCT; the main distinction being thickness. Given these similarities, these regions of nAMD-associated atrophy may be better-termed "atrosis" to distinguish these lesions from typical atrophy in the absence of neovascular disease.

Longitudinal Evaluation of the Distribution of Intraretinal Hyper-Reflective Foci in Eyes with Intermediate Age-Related Macular Degeneration.

PURPOSE: Intraretinal hyper-reflective foci (IHRF) are optical coherence tomography (OCT) risk factors for progression of age-related macular degeneration (AMD). In this study we assess the change in the number and distribution of IHRF over two years. METHODS: The axial distribution of IHRF were quantified in eyes with intermediate AMD (iAMD) at baseline and 24 months, using a series of 5 sequential equidistant en face OCT retinal slabs generated between the outer border of the internal limiting membrane (ILM) and the inner border of the retinal pigment epithelium (RPE). Following thresholding and binarization, IHRF were quantified in each retinal slab using ImageJ. The change in IHRF number in each slab between baseline and month 24 was calculated. RESULTS: Fifty-two eyes showed evidence of IHRF at baseline, and all continued to show evidence of IHRF at 24 months (M24). The total average IHRF count/eye increased significantly from 4.67 ± 0.63 at baseline to 11.62 ± 13.86 at M24 (p < 0.001) with a mean increase of 6.94 ± 11.12 (range: - 9 to + 60). Overall, at M24, 76.9% eyes showed an increase in IHRF whereas 15.4% of eyes showed a decrease (3 eyes [5.7%] showed no change). There was a greater number of IHRF and a greater increase in IHRF over M24 in the outer slabs. CONCLUSIONS: IHRF are most common in the outer retinal layers and tend to increase in number over time. The impact of the distribution and frequency of these IHRF on the overall progression of AMD requires further study.

Optical Coherence Tomography Features of Macular Hyperpigmented Lesions without Intraretinal Hyperreflective Foci in Age-Related Macular Degeneration.

PURPOSE: To evaluate the optical coherence tomography (OCT) features of hyperpigmented lesions in the absence of intraretinal hyperreflective foci (IHRF) on OCT in eyes with age-related macular degeneration (AMD). METHODS: We retrospectively analyzed OCT images of eyes with intermediate AMD (iAMD) and macular hyperpigmentation (HP) on color fundus photograph (CFP) but without IHRF on OCT in the corresponding location. The most prominent or definite HP was selected for analysis. The infrared reflectance (IR) image registered with the CFP, and the location corresponding to the HP lesion were defined on the IR image. The location of the HP on the corresponding OCT B-scan was assessed for retinal pigment epithelium (RPE) elevation, acquired vitelliform lesion (AVL), abnormal retinal pigment epithelium + basal lamina (RPE + BL) band reflectivity, RPE + BL band thickening, as well as interdigitation zone (IZ), ellipsoid zone (EZ) and external limiting membrane (ELM) disruption. RESULTS: 49 eyes (39 patients) were included in this study. Forty-six (94%) of the hyperpigmented lesions showed a thickened RPE + BL band. RPE + BL band reflectivity was increased in 37 (76%) of the lesions. RPE + BL band thickening, however, was not correlated with RPE + BL band reflectivity (p-value = 0.31). Either thickening or hyperreflectivity of the RPE + BL band was present in all cases. Twenty (41%) lesions had evidence of ELM disruption, 42 (86%) demonstrated EZ disruption and 48 (98%) had IZ disruption. Five (10%) HPs demonstrated AVL. Among cases with RPE elevation (15 cases, 31%), 10 were classified as drusen, 2 as drusenoid PEDs, and 3 as fibrovascular PEDs. CONCLUSIONS: Thickening and/or hyperreflectivity of the RPE + BL band commonly correspond to regions of macular hyperpigmentation without IHRF in eyes with iAMD.

Relationship between the distribution of intra-retinal hyper-reflective foci and the progression of intermediate age-related macular degeneration.

PURPOSE: To assess the relationship between the distribution of intra-retinal hyper-reflective foci (IHRF) on optical coherence tomography (OCT) and progression of intermediate age-related macular degeneration (iAMD) over 2 years. METHODS: Cirrus OCT volumes of the macula of subjects enrolled in the Amish Eye Study with 2 years of follow-up were evaluated for the presence of iAMD and IHRF at baseline. The IHRF were counted in a series of 5 sequential en face slabs from outer to inner retina. The number of IHRF in each slab at baseline and the change in IHRF from baseline to year 2 were correlated with progression to late AMD at 2 years. RESULTS: Among 120 eyes from 71 patients with iAMD, 52 eyes (43.3%) of 42 patients had evidence of both iAMD and IHRF at baseline. Twenty-three eyes (19.0%) showed progression to late AMD after 2 years. The total IHRF count increased from 243 at baseline to 604 at 2 years, with a significant increase in the IHRF number in each slab, except for the innermost slab 5 which had no IHRF at baseline or follow-up. The IHRF count increased from 121 to 340 in eyes that showed progression to late AMD. The presence of IHRF in the outermost retinal slabs 1 and 2 was independently associated with a significant risk of progression to late AMD. A greater increase in IHRF count over 2 years in these same slabs 1 and 2 was also associated with a higher risk of conversion to late AMD. CONCLUSIONS: The risk of progression to late AMD appears to be significantly associated with the distribution and extent of IHRF in the outermost retinal layers. This observation may point to significant pathophysiologic differences of IHRF in inner versus outer layers of the retina.

Ethnic Variation in Diabetic Retinopathy Lesion Distribution on Ultra-widefield Imaging.

PURPOSE: To evaluate whether the distribution of diabetic retinopathy (DR) lesions differs among various ethnicities. DESIGN: Multi-center, retrospective cohort study. METHODS: We accrued a cohort of 226 eyes with DR consisting of 51 East Asian eyes, 102 South Asian eyes, 30 Caucasian eyes, and 43 Latino eyes, all evaluated with ultrawide field pseudocolor images. Images were manually annotated for DR lesions and were classified as having predominantly peripheral lesions (PPL) or predominantly central lesions (PCL) using 4 quantitative methods. The percent distribution of PCL to PPL was compared among different ethnicities. RESULTS: Using a single-field lesion frequency-based method, East Asian eyes more frequently demonstrated a PPL distribution (86.3%), whereas South Asian eyes more frequently demonstrated a PCL distribution (64.7%). These findings were also observed when considering only the subset of treatment-naïve eyes. Furthermore, in treatment-naïve eyes without proliferative DR, the percent distribution of PPL to PCL in East Asian eyes was significantly different when compared to other ethnicities (P < .0001 South Asian, P = .035 Caucasian, P = .0003 Latino). The majority of patients (60%-78%) in all ethnic groups had moderate nonproliferative diabetic retinopathy(NPDR), and the same difference between East Asian and South Asian eyes was observed in this subgroup. CONCLUSIONS: The distribution of DR lesions appears to vary among different ethnicities. DR lesions tend to be distributed more peripherally in East Asian eyes compared to other ethnic groups, particularly South Asian eyes, which tend to have more central disease. The prognostic implications of these ethnic differences in DR lesion distribution require further investigation.

Risk Factors for Progression of Age-Related Macular Degeneration: Population-Based Amish Eye Study.

Objective: To evaluate the optical coherence tomography (OCT)-based risk factors for progression to late age-related macular degeneration (AMD) in a population-based study of elderly Amish. Methods: A total of 1332 eyes of 666 consecutive subjects who completed a 2-year follow-up visit were included in this multicenter, prospective, longitudinal, observational study. Imaging features were correlated with 2-year incidence of late AMD development. Odds ratios for imaging features were estimated from logistic regression. Baseline OCT images were reviewed for the presence of drusen volume ≥0.03 mm3 in the central 3 mm ring, intraretinal hyperreflective foci (IHRF), hyporeflective drusen cores (hDC), subretinal drusenoid deposits (SDD), and drusenoid pigment epithelium detachment (PED). Subfoveal choroidal thickness, drusen area, and drusen volume within 3 and 5 mm circles centered on the fovea were also assessed. Results: Twenty-one (1.5%) of 1332 eyes progressed to late AMD by 2 years. The mean age of the study subjects was 65 ± 10.17 (±SD) years and 410 subjects were female. Univariate logistic regression showed that drusen area and volume in both 3 mm and 5 mm circles, subfoveal choroidal thickness, drusen volume ≥ 0.03 mm3 in the 3 mm ring, SDD, IHRF, and hDC were all associated with an increased risk for development of late AMD. The multivariate regression model identified that drusen volume in the 3 mm ring (OR: 2.59, p = 0.049) and presence of IHRF (OR: 57.06, p < 0.001) remained as independent and significant risk factors for progression to late AMD. Conclusions: This population-based study confirms previous findings from clinic-based studies that high central drusen volume and IHRF are associated with an increased risk of progression to late AMD. These findings may be of value in risk-stratifying patients in clinical practice or identifying subjects for early intervention clinical trials.

Correlation between Fundus Autofluorescence and En Face OCT Measurements of Geographic Atrophy.

PURPOSE: To evaluate the correlation between fundus autofluorescence (FAF) and en face spectral-domain OCT (SD-OCT) measurements of geographic atrophy (GA) area associated with age-related macular degeneration. DESIGN: Retrospective, cross-sectional study. PARTICIPANTS: Two hundred seventy eyes from 172 subjects with GA associated with age-related macular degeneration. METHODS: Subjects with atrophic age-related macular degeneration who underwent both FAF (Heidelberg HRA + Spectralis) and dense volume (128 B-scans over 6 × 6 mm2) SD-OCT (Cirrus OCT) imaging were included in this retrospective analysis. The borders of all areas of definite decreased autofluorescence (DDAF) corresponding to GA were manually outlined on FAF images by certified graders at Doheny Image Reading Center using validated planimetric grading tools. Geographic atrophy was also automatically delineated using en face OCT (at the level of the choroid) using an instrument software (Cirrus v.6.2), and segmentation errors were manually corrected before the computation of the GA area. The fundus autofluorescence and SD-OCT-derived measurements were correlated. MAIN OUTCOME MEASURES: Correlation between the SD-OCT and FAF measurements of the GA area. RESULTS: The mean GA area measured from the FAF images was 8.1 ± 5.04 mm2, compared with an automated, uncorrected GA area of 6.82 ± 3.84 mm2 measured using SD-OCT. Despite the presence of apparent OCT segmentation errors, there was a significant correlation between the FAF and uncorrected SD-OCT measurements (r = 0.80; P < 0.001). After the manual correction of the SD-OCT GA segmentation errors, the measured GA area increased to 7.29 ± 4.18 mm2, and the correlation with the FAF-determined GA area significantly improved (r = 0.98; P < 0.001). CONCLUSIONS: Spectral-domain OCT-derived measurements of GA correlate well with areas of DDAF obtained from FAF images. The manual correction of SD-OCT segmentation errors can further improve this correlation. These observations may support the use of SD-OCT-based measurements of the GA area in clinical research and clinical trials.

Final Outcomes from the Randomized RECOVERY Trial of Aflibercept for Retinal Nonperfusion in Proliferative Diabetic Retinopathy.

PURPOSE: Retinal nonperfusion (RNP) is an important biomarker for diabetic retinopathy (DR). Data suggest that consistent anti-VEGF pharmacotherapy can slow RNP development. The RECOVERY trial evaluated the impact of aflibercept (Eylea, Regeneron) on RNP among eyes with proliferative DR (PDR). DESIGN: Prospective, randomized clinical trial with treatment crossover in the second year. SUBJECTS: Eyes with PDR and RNP. METHODS: At baseline, the subjects were randomized 1:1 to monthly (arm 1) or quarterly (arm 2) intravitreal 2 mg aflibercept. At the beginning of year 2, the treatment arms were crossed over so that the monthly-dosed subjects subsequently received quarterly dosing and the quarterly-dosed subjects subsequently received monthly dosing. MAIN OUTCOME MEASURES: Change in total RNP area (mm2) through year 2. Secondary outcomes included Diabetic Retinopathy Severity Scale (DRSS) scores; best-corrected visual acuity; central subfield thickness; additional measures of RNP, including ischemic index (ISI); and adverse event incidence. Means and 95% confidence intervals were calculated. RESULTS: Among all subjects, from baseline to year 2, the mean RNP increased from 235 mm2 to 402 mm2 (P < 0.0001), and the ISI increased from 25.8% to 50.4% (P < 0.0001). Increases in the mean RNP (P < 0.0001) and ISI (P < 0.0001) were also observed from year 1 to year 2. The mean total RNP increased from 264 mm2 at baseline to 386 mm2 (P < 0.0001) at year 2 in arm 1 and from 207 mm2 at baseline to 421 mm2 (P < 0.0001) at year 2 in arm 2 (P = 0.023, arm 1 vs. arm 2). Increases in the mean RNP for both treatment arms (P < 0.0001) were also specifically observed within year 2 (P = 0.32, arm 1 vs. arm 2). Compared with baseline, the DRSS scores at the end of year 2 improved in 82% (n = 27) of subjects and remained stable in 18% (n = 6), with no subjects experiencing worsening; at 2 years, the DRSS scores had improved by 2 or more steps in 65% (n = 11) and 81% (n = 13) of subjects in arms 1 and 2, respectively. CONCLUSIONS: Through year 2 of the RECOVERY trial, both treatment arms experienced significant increases in RNP. Despite the expansion of the RNP area in nearly all subjects, 82% of subjects demonstrated an improvement in DRSS levels from baseline, with no subjects experiencing worsening in DRSS scores.

The 2-Year Leakage Index and Quantitative Microaneurysm Results of the RECOVERY Study: Quantitative Ultra-Widefield Findings in Proliferative Diabetic Retinopathy Treated with Intravitreal Aflibercept.

Eyes with proliferative diabetic retinopathy (PDR) have been shown to improve in the leakage index and microaneurysm (MA) count after intravitreal aflibercept (IAI) treatment. The authors investigated these changes via automatic segmentation on ultra-widefield fluorescein angiography (UWFA). Forty subjects with PDR were randomized to receive either 2 mg IAI every 4 weeks (Arm 1) or every 12 weeks (Arm 2) through Year 1. After Year 1, Arm 1 switched to quarterly IAI and Arm 2 to monthly IAI through Year 2. By Year 2, the Arm 1 leakage index decreased by 43% from Baseline (p = 0.03) but increased by 59% from Year 1 (p = 0.04). Arm 2 decreased by 61% from Baseline (p = 0.008) and by 31% from Year 1 (p = 0.12). Both cohorts exhibited a significant decline in MAs from Baseline to Year 2 (871 to 410; p < 0.001; 776 to 207; p < 0.001, respectively). Subjects with an improved leakage and MA count showed a more significant improvement in the Diabetic Retinopathy Severity Scale (DRSS) score. Moreover, central subfield thickness (CST) was positively associated with changes in the leakage index. In conclusion, the leakage index and MA counts significantly improved from Baseline following IAI treatment, and monthly injections provided a more rapid and sustained reduction in these parameters compared with quarterly injections.

Automated identification of clinical features from sparsely annotated 3-dimensional medical imaging.

One of the core challenges in applying machine learning and artificial intelligence to medicine is the limited availability of annotated medical data. Unlike in other applications of machine learning, where an abundance of labeled data is available, the labeling and annotation of medical data and images require a major effort of manual work by expert clinicians who do not have the time to annotate manually. In this work, we propose a new deep learning technique (SLIVER-net), to predict clinical features from 3-dimensional volumes using a limited number of manually annotated examples. SLIVER-net is based on transfer learning, where we borrow information about the structure and parameters of the network from publicly available large datasets. Since public volume data are scarce, we use 2D images and account for the 3-dimensional structure using a novel deep learning method which tiles the volume scans, and then adds layers that leverage the 3D structure. In order to illustrate its utility, we apply SLIVER-net to predict risk factors for progression of age-related macular degeneration (AMD), a leading cause of blindness, from optical coherence tomography (OCT) volumes acquired from multiple sites. SLIVER-net successfully predicts these factors despite being trained with a relatively small number of annotated volumes (hundreds) and only dozens of positive training examples. Our empirical evaluation demonstrates that SLIVER-net significantly outperforms standard state-of-the-art deep learning techniques used for medical volumes, and its performance is generalizable as it was validated on an external testing set. In a direct comparison with a clinician panel, we find that SLIVER-net also outperforms junior specialists, and identifies AMD progression risk factors similarly to expert retina specialists.

Effect of Human Central Nervous System Stem Cell Subretinal Transplantation on Progression of Geographic Atrophy Secondary to Nonneovascular Age-Related Macular Degeneration.

PURPOSE: To evaluate the effect of subretinally transplanted human central nervous system stem cells (HuCNS-SC) on the progression of geographic atrophy (GA) in patients with nonneovascular age-related macular degeneration (AMD). DESIGN: Multicenter, prospective, phase 1 open-label clinical trial. PARTICIPANTS: Fifteen patients with bilateral GA solely the result of AMD. METHODS: The eye with the worst best-corrected visual acuity from each patient was selected for treatment and was considered the study eye; fellow eyes served as controls. A total of 0.25 × 106 or 1.0 × 106 HuCNS-SCs were infused directly into the subretinal space, superotemporal to the fovea near the junctional zone, outside the area of GA. All patients underwent spectral-domain OCT and fundus autofluorescence imaging using the Spectralis HRA+OCT (Heidelberg Engineering, Inc., Heidelberg, Germany). Total GA area in both eyes was measured at baseline and month 12 by certified reading center graders using the Spectralis Region Finder software. Sectoral (clock hour) per directional radial GA progression rates with respect to the foveal center in both eyes were calculated using the polar transformation method in Image J software (National Institutes of Health, Bethesda, MD). To facilitate comparative analysis across the cohort, all eyes were transformed to a right-eye orientation. MAIN OUTCOME MEASURES: Total GA area and sectoral per directional GA progression rates were compared in both study and control eyes. RESULTS: No statistically significant difference was found in mean change in total GA area at month 12 between study and fellow eyes (1.07 ± 0.84 mm2 vs. 2.08 ± 1.97 mm2; P = 0.08). However, the month 12 sectoral per directional radial GA growth rate for the superotemporal region (i.e., the location of HuCNS-SC transplantation) showed a significantly slower progression rate in study eyes than in fellow eyes (0.29 ± 0.58 mm vs. 1.08 ± 0.65 mm; P = 0.007). The progression rate in the superotemporal quadrant of the study eye was significantly slower than in the other 3 quadrants combined (P = 0.04). CONCLUSIONS: In this small pilot study, HuCNS-SC transplantation seems to be associated with slower expansion of the GA lesion in the transplanted quadrant. Larger confirmatory studies are required. Sectoral or directional analysis of growth rates of GA may be a useful approach for assessing the efficacy of locally delivered therapies.

Comparison and Correlation of Retinal Sensitivity Between Microperimetry and Standard Automated Perimetry in Low-tension Glaucoma.

PRéCIS:: Our study demonstrated that in low-tension glaucoma (LTG) patients, Microperimeter-3 (MP-3)-derived and Humphrey Field Analyzer (HFA)-derived retinal sensitivities were similar and strongly correlated, allowing the respective data to be interrelated. PURPOSE: To compare and correlate retinal sensitivities obtained by Nidek MP-3 with those obtained from the HFA in eyes with LTG. MATERIALS AND METHODS: In this prospective comparative study, 45 eyes of 24 LTG patients underwent retinal sensitivity assessments using the MP-3 (Nidek Technologies) and the HFA (Carl Zeiss Meditec) at the UCLA-Doheny Eye Center. Global and pointwise retinal sensitivity measurements were compared and correlated between the 2 devices. RESULTS: No statistically significant differences (P=0.85) were noted between the mean retinal sensitivities determined by each device (MP-3: 26.33±4.31 dB; range, 13.05 to 31.60 vs. HFA: 26.42±3.98 dB; range, 17.17 to 30.96), and a strong correlation (r=0.66, P<0.001) was noted for retinal sensitivity measurements. In addition, moderate to strong correlations were observed between the mean retinal sensitivity derived by MP-3 versus HFA-derived mean deviation (r=0.57, P<0.001), as well as, the pattern standard deviation (r=0.67, P<0.001). The intraclass correlation coefficient was excellent (ICC=0.80, 95% confidence interval, 0.63-0.89), while the Bland-Altman analysis showed good agreement between the 2 devices with respect to retinal sensitivity. CONCLUSION: Retinal sensitivity measurements obtained by the MP-3 microperimetry instrument and the standard automated HFA perimeter were similar and highly correlated in patients with LTG. Given the potential benefits of microperimetry technology such as auto-eye-tracking and potentially more precise structure-function correlations, the use of microperimetry to monitor visual function in glaucoma management warrants further consideration.

Quantitative Assessment of the Severity of Diabetic Retinopathy.

PURPOSE: To determine whether a quantitative approach to assessment of the severity of diabetic retinopathy (DR) lesions on ultrawide field (UWF) images can provide new parameters to predict progression to proliferative diabetic retinopathy (PDR). METHODS: One hundred forty six eyes from 73 participants with DR and 4 years of follow-up data were included in this post hoc analysis, which was based on a cohort of 100 diabetic patients enrolled in a previously published prospective, comparative study of UWF imaging at the Joslin Diabetes Center. Diabetic Retinopathy Severity Score level was determined at baseline and 4-year follow-up visits using mydriatic 7-standard field Early Treatment Diabetic Retinopathy Study (ETDRS) photographs. All individual DR lesions (hemorrhage [H], microaneurysm [ma], cotton wool spot [CWS], intraretinal microvascular abnormality [IRMA]) were manually segmented on stereographic projected UWF. For each lesion type, the frequency/number, surface area, and distances from the optic nerve head (ONH) were computed. These quantitative parameters were compared between eyes that progressed to PDR in 4 years and eyes that did not progress. Univariable and multivariable logistic regression analyses were performed to identify parameters that were associated with an increased risk for progression to PDR. RESULTS: A total of 146 eyes of 73 subjects were included in the final analysis. The mean age of the study cohort was 53.1 years, and 42 (56.8%) subjects were female. The number and surface area of H/ma's and CWSs were significantly (P ≤ .05) higher in eyes that progressed to PDR compared with eyes that did not progress by 4 years. Similarly, H/ma's and CWSs were located further away from the ONH (ie, more peripheral) in eyes that progressed (P < .05). DR lesion parameters that conferred a statistically significant increased risk for proliferative diabetic retinopathy in the multivariate model included hemorrhage area (odds ratio [OR], 2.63; 95% confidence interval [CI], 1.25-5.53), and greater distance of hemorrhages from the ONH (OR, 1.24; 95% CI, 0.97-1.59). CONCLUSIONS: Quantitative analysis of DR lesions on UWF images identifies new risk parameters for progression to PDR including the surface area of hemorrhages and the distance of hemorrhages from the ONH. Although these risk factors will need to be confirmed in larger, prospective studies, they highlight the potential for quantitative lesion analysis to inform the design of a more precise and complete staging system for diabetic retinopathy severity in the future. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Reproducibility and agreement of four anterior segment-optical coherence tomography devices for anterior chamber angle measurements.

PURPOSE: To compare the reproducibility and agreement of anterior chamber angle (ACA) parameters and metrics obtained by four different anterior segment-optical coherence tomography (AS-OCT) devices. METHODS: In this prospective study, 30 eyes from 15 normal subjects underwent anterior segment angle scanning using the Spectralis, Cirrus, and Optovue spectral domain optical coherence tomography (SD-OCT), as well as the Visante time-domain optical coherence tomography (TD-OCT). For each eye, the scan line was performed perpendicularly on the inferior (270°) angle, and the inferior ACA image was acquired 2 times. Inter-instrument and intra-instrument, as well as inter-observer and intra-observer reproducibility of anterior chamber angle metrics, Schwalbe's line (SL) to scleral spur (SS) distance (TM-Span), angle opening distance (AOD), and trabecular iris space area (TISA) measurements, were evaluated by intraclass correlation coefficients (ICCs) and Bland-Altman plots with limits of agreement (LoA). RESULTS: For this cohort of 30 eyes of 15 normal subjects, the mean TM-Span, AOD, and TISA were 0.966 ± 0.198 mm, 0.750 ± 0.205 mm, and 0.286 ± 0.090 mm2 from the Spectralis; 0.929 ± 0.113 mm, 0.717 ± 0.120 mm, and 0.267 ± 0.095 mm2 from the Cirrus; 0.923 ± 0.191 mm, 0.683 ± 0.161 mm, and 0.265 ± 0.072 mm2 from the Optovue; and 0.970 ± 0.070 mm, 0.705 ± 0.150 mm, and 0.279 ± 0.065 mm2 from the Visante. The intra-instrument (ICCs > 0.838), intra-grader (ICCs > 0.910), and inter-grader (ICCs > 0.869) agreement were good. Agreement between the four instruments was also good with ICCs from 0.901 to 0.967 for TM-Span, 0.887 to 0.941 for AOD, and 0.923 to 0.961 for TISA. CONCLUSIONS: Consistent and reproducible ACA measurements could be obtained from multiple AS-OCT devices including both SD- and TD-OCT instruments. These findings have relevance when considering multiple imaging devices in future studies.

CHOROIDAL VASCULARITY INDEX AND CHOROIDAL THICKNESS IN EYES WITH RETICULAR PSEUDODRUSEN.

PURPOSE: To evaluate choroidal vascularity index (CVI), choroidal thickness, choroidal volume, and choroidal intensity in subjects with nonneovascular age-related macular degeneration (NNVAMD) with and without reticular pseudodrusen (RPD). METHODS: We included 60 eyes of 35 subjects with NNVAMD (including 30 eyes of 18 subjects with RPD) and 30 eyes of 17 age-matched healthy individuals from the ongoing Amish Eye study. The choroid was segmented from dense volume spectral domain optical coherence tomography scans and choroidal thickness (microns), choroidal intensity (log units), and choroidal volume (mm) from the entire macula (6 × 6 mm) were computed. A central horizontal B-scan was binarized and the luminal and stromal portions of the choroid were segmented. Choroidal vascularity index (%) was calculated as the ratio of luminal area to total choroid area. Choroidal parameters were compared between the groups by pairwise comparisons using the Student's t-test. RESULTS: The CVI was significantly lower in healthy eyes compared to those with RPD (53.43 ± 8.51 vs. 54.76 ± 4.83, P < 0.001). The CVI was also significantly lower in NNVAMD eyes without RPD compared to those with RPD (50.09 ± 7.51 vs. 54.76 ± 4.83, P = 0.006). There was no difference in CVI between healthy eyes and NNVAMD eyes without RPD (P = 0.84). Choroidal thickness and choroidal volume were significantly higher in NNVAMD without RPD (P < 0.05); and significantly lower in NNVAMD with RPD (P < 0.05) when compared with normal eyes. Choroidal intensity was significantly higher in NNVAMD with RPD when compared with normal eyes (P = 0.02) and NNVAMD eyes without RPD (P = 0.001). CONCLUSION: Multiple choroidal parameters reflecting the status of the choroidal vasculature and stroma seem to be altered in eyes with RPD compared with both normal eyes and NNVAMD eyes without RPD. These findings may provide insights into the pathophysiology of RPD.

Effect of Intravitreal Ranibizumab on Intraretinal Hard Exudates in Eyes with Diabetic Macular Edema.

PURPOSE: To study the effect of monthly 0.3-mg intravitreal ranibizumab injections on intraretinal hard exudates (HEs) and correlate the effect with macular thickness in eyes with diabetic macular edema (DME). DESIGN: Randomized, controlled trial. METHODS: Twenty-four eyes of 24 subjects with DME were included in this institutional review board-approved, prospective longitudinal study. Subjects were randomly assigned to receive monthly intravitreal ranibizumab injections either until macular edema resolved or until both macular edema and HEs resolved. All subjects underwent spectral-domain optical coherence tomography imaging (Cirrus OCT), at baseline and monthly for 12 months. Mean HE area and mean macular thickness at baseline and month 12 were compared using a paired t test and correlated with Pearson analysis. RESULTS: The average age of the 24 subjects was 65 (±8.55) years. There was a significant decrease (P = .001) in mean HE area from baseline (0.48 ± 0.43 mm2) to month 12 (0.17 ± 0.19 mm2). There was a significant increase (P < .001) in best-corrected visual acuity from a letter score of 63.38 (±7.92) at baseline to 76.38 (±8.93) at month 12. There was no additional vision benefit for continuing to treat with monthly injections for persistent HE in the absence of macular thickening. CONCLUSION: In eyes with DME, monthly intravitreal ranibizumab injections resulted in significant reduction in intraretinal HEs that paralleled reductions in macular thickness and volume. Baseline foveal HEs were associated with worse vision outcomes, and continued treatment for persistent HEs in the absence of edema did not result in better vision.

Retinal Sensitivity Using Microperimetry in Age-Related Macular Degeneration in an Amish Population.

BACKGROUND AND OBJECTIVES: To evaluate retinal sensitivity (RS) by mesopic and scotopic microperimetry (MP-1S) in an elderly Amish population with age-related macular degeneration (AMD). PATIENTS AND METHODS: Mesopic and scotopic microperimetric testing was performed in 148 eyes of 77 elderly Amish subjects (age > 50 years) from Pennsylvania using a retinal function analyzer. Scotopic testing was performed using a 2.0 log unit neutral density filter following 30 minutes of dark adaptation. All subjects underwent complete ophthalmic examinations, including spectral-domain optical coherence tomography, fundus autofluorescence, infrared reflectance imaging, and flash color fundus photography. Certified graders at Doheny Image Reading Center identified subjects with evidence of AMD as defined by the Beckman classification and quantified drusen volume. RS in subjects with and without AMD was compared. Correlations between RS and drusen burden were analyzed. Ten eyes with incomplete MP-1S exams were excluded from the final analysis. RESULTS: Among the 138 eyes from 77 subjects included in the final analysis, 42 eyes from 29 subjects had evidence of early or intermediate AMD. The mean age of subjects with AMD was 69.65 years ± 13.81 years versus 63.04 years ± 12.69 years in those without AMD (P = .06). Mesopic RS was 18.8 dB ± 2.1 dB in subjects with AMD and 19.6 dB ± 1.4 dB in those without AMD (P = .07). Scotopic RS was significantly lower (P = .04) in subjects with AMD (15.9 dB ± 2.9 dB) compared with those without AMD (17.3 dB ± 2.4 dB). There was no relationship between mesopic RS and either drusen area (r = -0.06; P = .32) or drusen volume (r = -0.08; P = .30). There was a trend for an association between scotopic RS and both drusen area (r = -0.39; P = .24) and drusen volume (r = -0.36; P = .30). CONCLUSIONS: In an elderly Amish population, eyes with early or intermediate AMD show a greater reduction in scotopic RS than mesopic RS, suggesting that rod function is more severely affected than cone function. Drusen area and volume measurements better correlated with scotopic RS. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e236-e241.].

Intravitreal Aflibercept for Retinal Nonperfusion in Proliferative Diabetic Retinopathy: Outcomes from the Randomized RECOVERY Trial.

PURPOSE: Evaluate the impact of intravitreal aflibercept (Eylea; Regeneron, Tarrytown, NY) on retinal nonperfusion (RNP) in eyes with proliferative diabetic retinopathy (PDR). DESIGN: Prospective, randomized clinical trial. PARTICIPANTS: Eyes with treatment-naïve PDR and extensive RNP without diabetic macular edema. METHODS: Patients were randomized 1:1 to intravitreal 2 mg aflibercept every 4 weeks (monthly) or every 12 weeks (quarterly). MAIN OUTCOME MEASURES: The primary outcome measure was change in total RNP area (in square millimeters) from baseline to year 1. Secondary outcomes included ischemic index (ISI), diabetic retinopathy severity scale (DRSS) scores, visual acuity, central retinal thickness, and adverse events. The mean and 95% confidence interval were calculated for each outcome. RESULTS: Through 1 year, the monthly (n = 20) and quarterly (n = 20) cohorts received 11.0 and 3.95 mean aflibercept injections, and DRSS scores improved 2 steps or more in 74% and 67% of patients, respectively. Among all patients through 1 year, mean total area of RNP increased from 235 mm2 to 266 mm2 (P = 0.18) and ISI increased from 25.8% to 31.9% (P = 0.004). Retinal nonperfusion outcomes favored monthly dosing. Mean total RNP increased from 207 mm2 at baseline to 268 mm2 (P = 0.01) at 1 year in the quarterly cohort and remained stable at 264 mm2 at baseline and 1 year (P = 0.70) in the monthly cohort (P = 0.05, monthly vs. quarterly cohorts). Although many eyes demonstrated increased areas of RNP longitudinally (n = 24 [66.7%]), this was more common with quarterly dosing (n = 14 [77.8%]), and a proportion of eyes (n = 12 [33.3%]) demonstrated localized areas of apparent reperfusion of nonperfused retina, more commonly in the monthly cohort (n = 8 [44.4%]). CONCLUSIONS: Widespread evidence of retinal reperfusion with aflibercept dosing of PDR eyes with extensive RNP was not identified, and therefore the primary outcome of the current study was not met. Nevertheless, zones of apparent reperfusion were detected in some patients, and a dose response was identified with a reduction of RNP progression with monthly compared to quarterly dosing.

The Value of Automated Diabetic Retinopathy Screening with the EyeArt System: A Study of More Than 100,000 Consecutive Encounters from People with Diabetes.

Background: Current manual diabetic retinopathy (DR) screening using eye care experts cannot scale to screen the growing population of diabetes patients who are at risk for vision loss. EyeArt system is an automated, cloud-based artificial intelligence (AI) eye screening technology designed to easily detect referral-warranted DR immediately through automated analysis of patient's retinal images. Methods: This retrospective study assessed the diagnostic efficacy of the EyeArt system v2.0 analyzing 850,908 fundus images from 101,710 consecutive patient visits, collected from 404 primary care clinics. Presence or absence of referral-warranted DR (more than mild nonproliferative DR [NPDR]) was automatically detected by the EyeArt system for each patient encounter, and its performance was compared against a clinical reference standard of quality-assured grading by rigorously trained certified ophthalmologists and optometrists. Results: Of the 101,710 visits, 75.7% were nonreferable, 19.3% were referable to an eye care specialist, and in 5.0%, the DR level was unknown as per the clinical reference standard. EyeArt screening had 91.3% (95% confidence interval [CI]: 90.9-91.7) sensitivity and 91.1% (95% CI: 90.9-91.3) specificity. For 5446 encounters with potentially treatable DR (more than moderate NPDR and/or diabetic macular edema), the system provided a positive "refer" output to 5363 encounters achieving sensitivity of 98.5%. Conclusions: This study captures variations in real-world clinical practice and shows that an AI DR screening system can be safe and effective in the real world. This study demonstrates the value of this easy-to-use, automated tool for endocrinologists, diabetologists, and general practitioners to address the growing need for DR screening and monitoring.