Drusen morphometrics on optical coherence tomography in eyes with age-related macular degeneration and normal aging.

PURPOSE: To compare drusen size metrics (apical height and basal width) on optical coherence tomography (OCT) B-scans with their size assessed on color photos in eyes with age-related macular degeneration (AMD) and normal aging. METHODS: A total of 508 drusen were evaluated in this analysis. Flash color fundus photos (CFP), infrared reflectance (IR) images, and OCT B-scans obtained at the same visit were evaluated. Individual drusen were identified on CFPs and the diameters of the drusen were measured in planimetric grading software. CFPs were manually registered to the IR image with their corresponding OCT volume. After confirming correspondence between the CFP and OCT, the apical height and basal width of the same drusen were measured on OCT B-scans. RESULTS: Drusen were divided into small, medium, large, and very large categories based on their diameter on the CFP images (< 63, 63 to 124, 125 to 249, and [Formula: see text] 250 µm, respectively). The OCT apical height of small drusen on CFP ranged from 20 to 31 µm, while medium drusen ranged from 31 to 46 µm, large drusen ranged from 45 µm to 111 µm, and very large drusen ranged from 55 µm to 208 µm. The OCT basal width measured < 99 µm in small drusen, from 99 to 143 µm in medium drusen, from 141 to 407 µm in large drusen, and > 209 µm in very large drusen. CONCLUSION: Drusen of different size categories on color photographs may also be separated according to their apical height and basal width on OCT. The apical height and basal width ranges defined in this analysis may be of value in the design of an OCT-based grading scale for AMD.

The relationship of diabetic retinopathy severity scales with frequency and surface area of diabetic retinopathy lesions.

PURPOSE: To assess the relationship between qualitative diabetic retinopathy (DR) scales with the precise numbers and surface area of DR lesions within the Early Treatment Diabetic Retinopathy Study (ETDRS) standard seven field (S7F) region on ultrawide-field (UWF) color fundus images. METHODS: In this study, we collected UWF images from adult patients with diabetes. Poor-quality images and eyes with any pathology precluding assessment of DR severity were excluded. The DR lesions were manually segmented. DR severity was graded according to the International Clinical Diabetic Retinopathy (ICDR) and AA protocol by two masked graders within the ETDRS S7F. These lesions' numbers and surface area were computed and correlated against the DR scores using the Kruskal-Wallis H test. Cohen's Kappa was performed to determine the agreement between two graders. RESULTS: One thousand five hundred and twenty eyes of 869 patients (294 females, 756 right eyes) with a mean age of 58.7 years were included. 47.4% were graded as no DR, 2.2% as mild non-proliferative DR (NPDR), 24.0% as moderate NPDR, 6.3% as severe NPDR, and 20.1% as proliferative DR (PDR). The area and number of DR lesions generally increased as the ICDR level increased up to severe NPDR, but decreased from severe NPDR to PDR. There was perfect intergrader agreement on the DR severity. CONCLUSION: A quantitative approach reveals that DR lesions' number and area generally correlate with ICDR-based categorical DR severity levels with an increasing trend in the number and area of DR lesions from mild to severe NPDR and a decrease from severe NPDR to PDR.

NEW BIOMARKER QUANTIFYING THE EFFECT OF ANTI-VEGF THERAPY IN EYES WITH PROLIFERATIVE DIABETIC RETINOPATHY ON ULTRAWIDE FIELD FLUORESCEIN ANGIOGRAPHY: RECOVERY Study.

PURPOSE: To quantify changes of the retinal vascular bed area (RVBA) in mm2 on stereographically projected ultrawide field fluorescein angiography images in eyes with proliferative diabetic retinopathy after antivascular endothelial growth factor injection. METHODS: This is a prospective, observational study. The early-phase ultrawide field fluorescein angiography images (Optos 200Tx) of 40 eyes with proliferative diabetic retinopathy and significant nonperfusion obtained at baseline and after six months (NCT02863354) were stereographically projected by correcting peripheral distortion. The global retinal vasculature on ultrawide field fluorescein angiography was extracted for calculating RVBA by summing the real size (mm2) of all the pixels automatically. RESULTS: For the entire cohort, the global RVBA for the entire retina decreased from 67.1 ± 15.5 to 43.6 ± 18.8 mm2 after anti-VEGF treatment at six months (P < 0.001). In the subgroup receiving monthly anti-VEGF injections, the global RVBA decreased from 68.7 ± 16.2 to 33.9 ± 13.3 mm2 (P < 0.001). In the subgroup receiving anti-VEGF every three months, the global RVBA decreased from 65.6 ± 15.1 to 50.8 ± 19.3 mm2 (P = 0.004). CONCLUSION: RVBA seems to be a new biomarker to indicate efficiency of retinal vascular changes after anti-VEGF injection. Eyes with proliferative diabetic retinopathy and significant nonperfusion demonstrate reduced RVBA after anti-VEGF treatment.

COMPARISON OF SPECTRALIS AND CIRRUS OPTICAL COHERENCE TOMOGRAPHY FOR THE DETECTION OF INCOMPLETE AND COMPLETE RETINAL PIGMENT EPITHELIUM AND OUTER RETINAL ATROPHY.

PURPOSE: To evaluate and compare the detection of incomplete and complete retinal pigment epithelial and outer retinal atrophy (iRORA and cRORA) using Spectralis and Cirrus optical coherence tomography (OCT) devices. METHODS: Subjects with late age-related macular degeneration were imaged on the same day with Spectralis and Cirrus OCT. Two, masked, independent, and experienced retina specialist graders evaluated each case for the presence of cRORA and iRORA lesions. RESULTS: A significantly higher number of lesions were observed using Spectralis compared with Cirrus (239 vs. 226 and 223 vs. 209). Higher number of iRORA lesions were identified with Spectralis (105 vs. 90 and 96 vs. 82), and no significant difference was observed between devices for cRORA lesions (134 vs. 136 and 128 vs. 126). When considering the presence or absence of iRORA or cRORA, the agreement between devices for both graders was excellent for cRORA and good for iRORA. CONCLUSION: Spectralis and Cirrus OCT identified a similar number of cRORA lesions, although more iRORA lesions could be detected with Spectralis OCT. These findings may have implications for developing acquisition protocols for trials based on the intended atrophy targets and highlight the importance of using a consistent OCT instrument across a study.

CHORIOCAPILLARIS FLOW DEFICITS AS A RISK FACTOR FOR PROGRESSION OF AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To evaluate the association between choriocapillaris (CC) flow deficits and structural optical coherence tomography biomarkers and the progression of intermediate age-related macular degeneration (iAMD) to complete retinal pigment epithelial and outer retinal atrophy. METHODS: Retrospective analysis of consecutive patients with iAMD with a minimum follow-up of 12 months. Odds ratios of intraretinal hyperreflective foci, hyporeflective drusen cores, subretinal drusenoid deposits, the presence of drusen volume ≥0.03 mm3 within a central 3-mm circle, fellow eye with late stage of AMD, and CC flow deficits at baseline and months of follow-up were estimated from logistic regression. RESULTS: A total of 112 eyes with iAMD were included. Eyes that progressed were significantly more likely to show intraretinal hyperreflective foci, hyporeflective drusen cores, and drusen volume ≥0.03 mm3. The CC flow deficit was also significantly greater in eyes that developed complete retinal pigment epithelial and outer retinal atrophy. Intraretinal hyperreflective foci, hyporeflective drusen cores, drusen volume ≥0.03 mm3, and higher CC flow deficits were significantly and independently associated with the development of complete retinal pigment epithelial and outer retinal atrophy. CONCLUSION: The CC flow deficit was significantly greater in iAMD eyes that progressed to complete retinal pigment epithelial and outer retinal atrophy and remained an independent risk factor when structural optical coherence tomography biomarkers were considered. CC flow deficits may be useful for enhancing risk stratification and prognostication of patients with iAMD.

Choriocapillaris flow impairment predicts the development and enlargement of drusen.

PURPOSE: To evaluate the choriocapillaris flow in regions of enlarged or new incident drusen in patients with early and intermediate age-related macular degeneration (AMD). METHODS: We retrospectively reviewed and analyzed structural optical coherence tomography (OCT) and OCT angiography (OCTA) images of consecutive patients with early or intermediate AMD evaluated at the Doheny-UCLA Eye Centers between 2015 and 2018. All patients were imaged using a Cirrus OCT, and only one eye was included in the study. To be eligible for this analysis, patients were required to have a 3 × 3-mm OCTA scan acquired during the first visit (considered as baseline) and a fovea-centered 512 × 128 macular cube (6 × 6 mm) acquired at both the baseline visit and after a minimum of 1 year follow-up. The drusen maps generated from the macular cubes were used to generate a drusen area (DA) measurement and compute the difference between baseline and follow-up (ΔDA). After registering the structural OCTs to the baseline choriocapillaris (CC) OCTA, we analyzed and compared the baseline flow deficits (FD) within drusen-free region (FDDF), regions into which drusen enlarged or expanded at follow-up (FDEN), and regions in which new incident drusen (FDND) appeared at follow-up. RESULTS: Forty-six patients were eligible for the analysis and had a mean follow-up of 1.47 years. Twelve eyes of 12 subjects had a ΔDA < 0.1 mm2. In these eyes, only the FDDF was calculated (40.37 ± 2.29%) and it was not significantly different from the FDDF of eyes with ΔDA ≥ 0.1 mm2 (40.25 ± 4.37%, p = 0.849). When comparing the different regions within the eyes with ΔDA ≥ 0.1 mm2, there was no significant difference between FDED and FDND (43.61 ± 4.36% and 44.16 ± 2.38%, p = 528), but both were significantly higher than FDDF (p = 0.001 and p < 0.001, respectively). CONCLUSIONS: Significant CC flow impairment is present under regions of intact retinal pigment epithelium (RPE) where existing drusen will enlarge into or new drusen will appear within 2 years. These findings suggest that location of drusen may not be stochastic but may be driven by regional deficits in the choriocapillaris.

Directional kinetics analysis of the progression of geographic atrophy.

PURPOSE: To investigate the influence of baseline geographic atrophy (GA) size on the rate of GA progression by using both distance and area measurements. METHODS: Thirty-five eyes from 24 patients with GA due to age-related macular degeneration were obtained from anonymized datasets available at the Doheny Image Reading Center. Baseline and month 12 fundus autofluorescence (FAF) images were used for this analysis. Borders of GA lesions were semiautomatically segmented by certified reading center graders to create masks of the GA lesion. The masks from the two visits were registered and overlaid to allow the differences in area as well as the differences in the position of GA border between the visits to be computed. Distance measurements were performed using a Euclidean distance map. Sectoral (clock hour)/directional GA progression rates with respect to the foveal center were also calculated. RESULTS: GA progressed 1.6 ± 0.9 mm2 in area and 92.9 ± 64.9 µm in distance over the 12 months. Smaller GA lesions were associated with more rapid progression when measured using distance (P = 0.0004, R = - 0.554). In contrast, there was no significant correlation in this cohort between baseline GA area and the progression measured in area (P = 0.406). In the sectoral/directional GA progression analysis, progression speed differed among clockwise directions, when progression was evaluated by using area measurements. However, this difference was not found, when evaluated by using distance measurements. CONCLUSIONS: Use of linear distance-based measurements enables evaluation of GA progression which is not confounded by baseline lesion size.

Impact of segmentation density on spectral domain optical coherence tomography assessment in Stargardt disease.

PURPOSE: Automated spectral domain optical coherence tomography (SD-OCT) segmentation algorithms currently do not perform well in segmenting individual intraretinal layers in eyes with Stargardt disease (STGD). We compared selective B-scan segmentation strategies for generating mean retinal layer thickness and preserved area data from SD-OCT scans in patients with STGD1. METHODS: Forty-five eyes from 40 Stargardt patients were randomly selected from the ongoing Natural History of the Progression of Atrophy Secondary to Stargardt Disease (ProgStar) study. All eyes underwent SD-OCT using a standard macular volume consisting of 1024 × 49 equally spaced B-scans within a 20 × 20 degree field centered on the fovea. All 49 B-scans were segmented manually to quantify total retina, outer nuclear layer (ONL), photoreceptor inner segments, photoreceptor outer segments (OS), and retinal pigment epithelial layer (RPE). Mean thickness and total area were generated using all 49 B-scans (spaced 122 µm apart), 25 B-scans (every other B-scan, spaced 240 µm apart), 17 B-scans (every third scan, 353 µm apart), and 13 B-scans (every fourth scan, 462 µm apart), as well as by using an "adaptive" method where a subset (minimum 25 B-scans) of B-scans that the grader deemed as significantly different from adjacent B-scans were utilized. Mean absolute and percentage errors were calculated for macular thickness and area of different retinal layers for the different B-scan subset selection strategies relative to using all 49 B-scans, which was considered the reference or ground truth. RESULTS: Mean thickness and area measurements were significantly different for any regularly spaced reduction in B-scan density relative to the ground truth. When an adaptive approach was applied using a minimum of half the scans, the differences relative to ground truth were no longer significantly different. The mean percent differences for the area and thicknesses of the various layers ranged from 0.02 to 33.66 (p < 0.05 for all comparisons) and 0.44 to 7.24 (p > 0.05) respectively. CONCLUSION: Manual segmentation of a subset of B-scans using an adaptive strategy can yield thickness and area measurements of retinal sublayers comparable to the reference ground truth derived from using all B-scans in the volume. These results may have implications for increasing the efficiency of SD-OCT grading strategies in clinical trials for STGD and other related macular degenerative disorders.

CLASSIFICATION AND QUANTITATIVE ANALYSIS OF GEOGRAPHIC ATROPHY JUNCTIONAL ZONE USING SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY.

PURPOSE: The junctional zone at the border of areas of geographic atrophy (GA) in eyes with nonneovascular age-related macular degeneration is an important target region for future therapeutic strategies. The goal of this study was to perform a detailed classification and quantitative characterization of the junctional zone using spectral domain optical coherence tomography. METHODS: Spectral domain optical coherence tomography volume cube scans (Spectralis OCT, 1024 × 37, Automatic Real Time > 9) were obtained from 15 eyes of 11 patients with GA because of nonneovascular age-related macular degeneration. Volume optical coherence tomography data were imported into previously described validated grading software (3D-OCTOR), and manual segmentation of the retinal pigment epithelium (RPE) and photoreceptor layers was performed on all B-scans (total of 555). Retinal pigment epithelium and photoreceptor defect maps were produced for each case. The borders of the photoreceptor defect area and RPE defect area were delineated individually on separate annotation layers. The two outlines were then superimposed to compare the areas of overlap and nonoverlap. The perimeter of the RPE defect area was calculated by the software in pixels. The superimposed outline of the photoreceptor defect area and the RPE defect area was scrutinized to classify the overlap configuration of the junctional zone into one of three categories: Type 0, exact correspondence between the edge of the RPE defect and photoreceptor defect; Type 1, loss of photoreceptors outside and beyond the edge of the RPE defect; Type 2, preservation of photoreceptors beyond the edge of the RPE defect. The relative proportion of the various border configurations was expressed as a percentage of the perimeter of the RPE defect. Each configuration was then classified into four subgroups according to irregularity of the RPE band and the presence of debris. RESULTS: Fifteen eyes of 11 patients (mean age: 79.3 ± 4.3 years; range: 79-94 years) were included in this study. Seventeen GA lesions were analyzed. Two hundred and thirty-two B-scans were found to pass through the GA lesions, yielding 612 individual GA borders which were separately analyzed and classified. The mean area of the RPE defect was 4.0 ± 4.4 mm, which was significantly smaller than that of the photoreceptor defect which measured 4.4 ± 4.1 mm (paired t test, P = 0.037). On average, 18.0 ± 9.6% (range, 2.3-36.6%) of the junctional zone was of the Type 0 configuration, 57.3 ± 19.0% (range, 21.3-96.8%) was Type 1, and 24.7 ± 18.0% (range, 0.9-64.4%) was Type 2. Type 1 was more prevalent than Type 0 and 2 (analysis of variance, P = 0.000). Debris was present at the margin of the defect in 24.3% (149 of 612) of all assessed junctional zones; 20.0% (14 of 70) of Type 0 junctions, 28.7% (120 of 418) of Type 1, and 12.1% (15 of 124) of Type 2. Debris was more common in Type 1 than Type 2 junctions (P < 0.001). Retinal pigment epithelial irregularity was present at the margin of the defect in 34.8% (213 of 612) of all assessed junctional zones; 52.9% (37 of 70) of Type 0 junctions, 38.0% (159 of 418) of Type 1, and 13.7% (17 of 124) of Type 2. Retinal pigment epithelial irregularity was present more often at Type 0 and Type 1 than at Type 2 junctions (P < 0.001 for both). CONCLUSION: The size of the optical coherence tomography-visible RPE and photoreceptor defect in GA lesions differ significantly. There were significant areas where the photoreceptor outer segments were preserved despite the absence of visible RPE cells, and also areas of photoreceptor outer segment loss despite apparent RPE preservation. These findings have implications for development of therapeutic strategies, particularly cell-replacement approaches.

En Face and Volumetric Comparison of Hypertransmission Defects Evaluated by Cirrus and Spectralis Optical Coherence Tomography.

PURPOSE: To evaluate and compare en face and 3-dimensional (3-D) properties of hypertransmission defects (HTDs) between different optical coherence tomography (OCT) devices using OCT volumes and reconstructed en face images. SETTINGS: Comparative diagnostic evaluation study. METHODS: Thirty eyes with dry age-related macular degeneration (AMD) that underwent dense OCT macular volume scans with both the Spectralis (97 B-scans/volume; 2910 B-scans in total) and Cirrus OCT (128 B-scans/volume; 3840 B-scans in total) from the Amish Eye Study cohort were included in this analysis. HTD regions were labeled on each B-scan and reconstructed into en face and 3-D volume images. Properties of HTD volume were compared between the 2 devices. RESULTS: The qualitative score of en face images for HTD was higher for the Cirrus compared to the Spectralis (P < .01). The quality of Spectralis en face images improved after preprocessing and reconstruction. The 2-D HTD area on en face obtained from 2-D projections of 3-D volume did not differ between devices (P = .478, ICC = 0.998; Jaccard index 0.721 ± 0.086). There was no difference in the number, volume, PALs, and surface areas of HTDs between devices in the volumetric analysis (all P ≥ .090). The signal intensity of HTD normalized by the mean choroidal signal intensity did not differ between devices (P = .861). CONCLUSIONS: The visualization of HTD on en face images from Spectralis OCT could be enhanced through image processing. The equivalence in 3-D HTD parameters between the 2 devices suggests interchangeability for assessing these lesions in AMD.

Atrophic Lesions Associated with Age-Related Macular Degeneration: High-Resolution versus Standard OCT.

OBJECTIVE: The objective of this study was to determine whether high-resolution OCT (HR-OCT) could enhance the identification and classification of atrophic features in age-related macular degeneration (AMD) compared with standard resolution OCT. DESIGN: Prospective, observational, cross-sectional study. SUBJECTS: The study included 60 eyes from 60 patients > 60 years of age with a diagnosis of AMD. METHODS: The participants underwent volume OCT scanning using HR-OCT and standard resolution OCT devices. Trained graders reviewed and graded the scans, identifying specific regions of interest for subsequent analysis. MAIN OUTCOME MEASURES: The study focused on identifying and classifying complete retinal pigment epithelium (RPE) and outer retinal atrophy (cRORA), incomplete RORA (iRORA), and other nonatrophic AMD features. Additionally, qualitative and quantitative features associated with atrophy were assessed. RESULTS: The agreement among readers for classifying atrophic lesions was substantial to perfect for both HR-OCT (0.88) and standard resolution OCT(0.82). However, HR-OCT showed a higher accuracy in identifying iRORA lesions compared with standard OCT. Qualitative assessment of features demonstrated higher agreement for HR-OCT, particularly in identifying external limiting membrane (ELM) (0.95) and ellipsoid zone (EZ) disruption (0.94). Quantitative measurements of features such as hypertransmission defects, RPE attenuation/disruption, EZ disruption width, and ELM disruption width showed excellent interreader agreement with HR-OCT (> 0.90 for all features) but only moderate agreement with standard OCT (0.51-0.60). CONCLUSIONS: The study results suggest that HR-OCT improves the accuracy and reliability of classifying and quantifying atrophic lesions associated with AMD compared with standard resolution OCT. The quantitative findings in particular may have implications for future research and clinical practice, especially with the availability of therapeutic agents for treating geographic atrophy and the development of commercially available HR-OCT devices. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Assessment of intraretinal hyperreflective foci using multimodal imaging in eyes with age-related macular degeneration.

PURPOSE: This study aimed to investigate the correspondence between intraretinal hyperreflective foci (IHRF) identified on optical coherence tomography (OCT) B-scans with hyperpigmentation on colour fundus photography (CFP) or hyperreflectivity on infrared reflectance (IR) images in eyes with age-related macular degeneration (AMD). METHODS: Flash CFP, IR images and OCT B-scans obtained at the same visit were evaluated. Individual IHRF identified on OCT B-scans were assessed for the qualitative presence or absence of a hypotransmission tail into the choroid. The corresponding IR image obtained at the time of OCT acquisition was analysed for the presence or absence of hyperreflectivity in this region. The IR images were manually registered to the CFP image, and CFP images were inspected for the presence or absence of hyperpigmentation at the location of IHRF. RESULTS: From 122 eyes, a total of 494 IHRF were evaluated. For the primary analysis of qualitative presence or absence of hyperpigmentation on CFP and hyperreflectivity on IR at the locations corresponding to IHRF on OCT, 301 (61.0%) of the IHRFs demonstrated evidence of hyperpigmentation on CFP, while only 115 (23.3%) showed evidence of hyperreflectivity on IR. The qualitative determination of the presence or absence of an abnormality on CFP or IR were significantly different (p < 0.0001). 327 (66.2%) of the IHRF showed hypotransmission, and 80.4% of these IHRF showed hyperpigmentation on CFP, though only 23.9% (p < 0.0001) demonstrated hyperreflectivity on IR. CONCLUSIONS: Less than two-thirds of IHRF evident on OCT manifest as hyperpigmentation on colour photos, though IHRF with posterior shadowing are more likely to be evident as pigment. IR imaging appears to be even more poorly sensitive for visualizing IHRF.

Prediction of Long-Term Treatment Outcomes for Diabetic Macular Edema Using a Generative Adversarial Network.

Purpose: The purpose of this study was to analyze optical coherence tomography (OCT) images of generative adversarial networks (GANs) for the prediction of diabetic macular edema after long-term treatment. Methods: Diabetic macular edema (DME) eyes (n = 327) underwent anti-vascular endothelial growth factor (VEGF) treatments every 4 weeks for 52 weeks from a randomized controlled trial (CRTH258B2305, KINGFISHER) were included. OCT B-scan images through the foveal center at weeks 0, 4, 12, and 52, fundus photography, and retinal thickness (RT) maps were collected. GAN models were trained to generate probable OCT images after treatment. Input for each model were comprised of either the baseline B-scan alone or combined with additional OCT, thickness map, or fundus images. Generated OCT B-scan images were compared with real week 52 images. Results: For 30 test images, 28, 29, 15, and 30 gradable OCT images were generated by CycleGAN, UNIT, Pix2PixHD, and RegGAN, respectively. In comparison with the real week 52, these GAN models showed positive predictive value (PPV), sensitivity, specificity, and kappa for residual fluid ranging from 0.500 to 0.889, 0.455 to 1.000, 0.357 to 0.857, and 0.537 to 0.929, respectively. For hard exudate (HE), they were ranging from 0.500 to 1.000, 0.545 to 0.900, 0.600 to 1.000, and 0.642 to 0.894, respectively. Models trained with week 4 and 12 B-scans as additional inputs to the baseline B-scan showed improved performance. Conclusions: GAN models could predict residual fluid and HE after long-term anti-VEGF treatment of DME. Translational Relevance: The implementation of this tool may help identify potential nonresponders after long-term treatment, thereby facilitating management planning for these eyes.

Spectral-domain OCT characteristics of intraretinal hyper-reflective foci associated with age-related macular degeneration and diabetic retinopathy.

OBJECTIVE: The purpose of this study was to quantitatively analyze and compare OCT characteristics of intraretinal hyper-reflective foci (IHRF) in eyes with diabetic retinopathy (DR) versus age-related macular degeneration (AMD). DESIGN: a retrospective observational study. PARTICIPANTS: 54 treatment-naïve eyes (27 DR and 27 AMD). METHODS: The IHRF lesions in OCT B-scan were semi-automatically segmented. Mean reflectivity (MR), maximum diameter, circularity index (Cir), area, and the angle between the greatest linear dimension (GLD) and the horizontal were computed for each IHRF lesion. The presence and absence of a posterior shadow and the axial location were assessed. The MR was normalized using the vitreous and nerve fiber layer reflectance as dark and bright reference standards, respectively. RESULTS: A total of 1149 IHRF (1051 in DR and 98 in the AMD group) were identified, with a mean of 39 ± 36 lesions in DR eyes compared to only 4 ± 4 in AMD eyes (p < 0.001). The mean area of individual IHRF lesions was greater in DR eyes (1305 ± 1647 µm² vs 1031 ± 750 µm²; p = 0.016), but IHRF in AMD eyes had higher reflectivity (1.17 ± 0.14 vs 1.03 ± 0.17; p < 0.001). The angle of the GLD relative to the horizontal was greater in AMD eyes, indicating that IHRF in AMD eyes were more horizontally oriented. In AMD eyes, 88.8% of IHRF were located beneath the inner border of the outer nuclear layer (ONL), while in DR eyes, 56.9% were located there (p < 0.001). CONCLUSIONS: IHRF lesions in eyes with DR and AMD demonstrate significant differences, with IHRF in DR eyes tending to be larger and less hyper-reflective compared to AMD eyes.

Retinal Imaging Findings in Inherited Retinal Diseases.

Inherited retinal diseases (IRDs) represent one of the major causes of progressive and irreversible vision loss in the working-age population. Over the last few decades, advances in retinal imaging have allowed for an improvement in the phenotypic characterization of this group of diseases and have facilitated phenotype-to-genotype correlation studies. As a result, the number of clinical trials targeting IRDs has steadily increased, and commensurate to this, the need for novel reproducible outcome measures and endpoints has grown. This review aims to summarize and describe the clinical presentation, characteristic imaging findings, and imaging endpoint measures that are being used in clinical research on IRDs. For the purpose of this review, IRDs have been divided into four categories: (1) panretinal pigmentary retinopathies affecting rods or cones; (2) macular dystrophies; (3) stationary conditions; (4) hereditary vitreoretinopathies.

OCT outcomes as biomarkers for disease status, visual function, and prognosis in diabetic macular edema.

OBJECTIVE: To evaluate disorganization of retinal inner layers (DRIL), as detected on spectral-domain optical coherence tomography (OCT) images, as a biomarker for diabetic macular edema (DME) activity, visual function, and prognosis in eyes with DME. DESIGN: Longitudinal prospective. METHODS: Post hoc correlation analyses were performed on data from a phase 2 clinical trial. Seventy-one eyes of 71 patients with treatment-naive DME received either suprachoroidally administered CLS-TA (proprietary formulation of a triamcinolone acetonide injectable suspension) combined with intravitreal aflibercept or intravitreal aflibercept with a sham suprachoroidal injection procedure. DRIL area, maximum horizontal extent of DRIL, ellipsoid zone (EZ) integrity, and the presence and location of subretinal (SRF) and intraretinal fluid (IRF) were evaluated at baseline and week 24 by certified reading centre graders. RESULTS: At baseline, the area and maximum horizontal extent of DRIL were negatively correlated with best-corrected visual acuity (BCVA; r = -0.25, p = 0.05 and r = -0.32, p =0.01, respectively). Mean baseline BCVA progressively worsened with each ordinal drop in EZ integrity, improved with the presence of SRF, and was invariant to the presence of IRF. DRIL area and maximum extent were significantly decreased at week 24 (-3.0 mm2 [p < 0.001] and -775.8 mm [p < 0.001], respectively. At week 24, decreases in the area and maximum horizontal extent of DRIL were positively correlated with increases in BCVA (r = -0.40, p = 0.003 and r = -0.30, p = 0.04). Improvements in BCVA at week 24 were no different between patients showing improvement in EZ, SRF, or IRF and those showing no improvement or worsening from baseline. CONCLUSIONS: DRIL area and DRIL maximum horizontal extent were demonstrated to be novel biomarkers for macular edema status, visual function, and prognosis in eyes with treatment-naive DME.

Alterations of the Ganglion Cell Complex in Age-Related Macular Degeneration: An Amish Eye Study Analysis.

PURPOSE: To compare the ganglion cell complex (GCC) thickness in eyes with age-related macular degeneration (AMD) vs healthy controls in an elderly Amish population. DESIGN: Prospective cross-sectional study. METHODS: This is a post hoc analysis of the family-based prospective study of Amish subjects. Study subjects underwent imaging with the Cirrus HD-OCT (Carl Zeiss Meditec Inc) using a macular cube protocol of 512 × 128 scans (128 horizontal B-scans, each comprising 512 A-scans) over a 6 mm × 6 mm region centered on the fovea. The ganglion cell analysis algorithm calculated the GCC thickness by segmenting the outer boundaries of the retinal nerve fiber layer (RNFL) and inner plexiform layer (IPL) in all B-scans of the volume, with the region between these boundaries representing the combined thickness of the ganglion cell layer (GCL) and the IPL. A number of parameters were used to evaluate the GCC thickness: the average GCC thickness, minimum (lowest GCC thickness at a single meridian crossing the elliptical annulus), and sectoral (within each of 6 sectoral areas: superior, superotemporal, superonasal, inferior, inferonasal, and inferotemporal). The stage of AMD was graded on color fundus photographs in accordance with the Beckman Initiative for Macular Research classification system. RESULTS: Of 1339 subjects enrolled in the Amish eye study, a total of 1294 eyes of 1294 subjects had all required imaging studies of sufficient quality and were included in the final analysis. Of these, 798 (62%) were female. Following age adjustment, the average GCC thickness was significantly (P < .001) thinner in AMD subjects (73.71 ± SD; 13.77 µm) compared to normals (77.97 ± 10.42 µm). An independent t test showed that the early AMD (75.03 ± 12.45 µm) and late AMD (61.64 ± 21.18 µm) groups (among which eyes with geographic atrophy [GA] had the lowest thickness, of 58.10 ± 20.27 µm) had a statistically significant lower GCC thickness compared to eyes without AMD. There was no significant differences in average GCC thickness between early AMD and intermediate AMD (76.36 ± 9.25 µm) eyes. CONCLUSIONS: The GCC thickness in AMD eyes is reduced compared to normal eyes; however, the relationship is complex, with the greatest reduction in late AMD eyes (particularly eyes with GA) but no difference between early and intermediate AMD eyes.

Comparison of diabetic retinopathy severity grading on ETDRS 7-field versus ultrawide-field assessment.

OBJECTIVES: To compare the diabetic retinopathy (DR) severity level determined when considering only the ETDRS 7-field region versus the entire ultrawidefield (UWF) image. METHODS: In this retrospective, cross-sectional study, UWF pseudocolor images were graded on the Eyenuk image viewing, grading, and annotation platform for the severity of DR considering only the regions within the ETDRS 7-fields as well as the entire UWF image using two different protocols: 1) the simple International Classification of Diabetic Retinopathy (ICDR) scale and 2) the more complex DRCR.net Protocol AA grading scale. RESULTS: A total of 250 eyes from 157 patients were included in this analysis. Six eyes (2.4%) demonstrated a discrepancy in severity level between the ETDRS 7-field region and the entire UWF image when using the ICDR classification system. The discrepancies were due to the presence of lesions [intraretinal haemorrhage (n = 2), neovascular disease (n = 4)] in the peripheral fields which were not identified in the ETDRS 7-fields. Fourteen eyes (5.6%) had a discrepancy in severity level between the ETDRS 7-field region and the entire UWF image when using the ETDRS DRSS Protocol AA grading scale. The discrepancies were due to the presence of a higher level of disease [intraretinal haemorrhage (n = 4), neovascularization (n = 4), preretinal haemorrhage (n = 2), scatter laser scars (n = 4)] in the peripheral fields. CONCLUSION: Although considering regions outside of the ETDRS 7-fields altered the DR severity level assessment in <5% of cases in this cohort, significant and potentially vision-threatening lesions including neovascularization and preretinal haemorrhage were identified in these peripheral regions. This highlights the importance of evaluating the entire UWF region when assessing patients with diabetic retinopathy.

Automated Identification of Incomplete and Complete Retinal Epithelial Pigment and Outer Retinal Atrophy Using Machine Learning.

OBJECTIVE: To assess and validate a deep learning algorithm to automatically detect incomplete retinal pigment epithelial and outer retinal atrophy (iRORA) and complete retinal pigment epithelial and outer retinal atrophy (cRORA) in eyes with age-related macular degeneration. DESIGN: In a retrospective machine learning analysis, a deep learning model was trained to jointly classify the presence of iRORA and cRORA within a given B-scan. The algorithm was evaluated using 2 separate and independent datasets. PARTICIPANTS: OCT B-scan volumes from 71 patients with nonneovascular age-related macular degeneration captured at the Doheny-University of California Los Angeles Eye Centers and the following 2 external OCT B-scans testing datasets: (1) University of Pennsylvania, University of Miami, and Case Western Reserve University and (2) Doheny Image Reading Research Laboratory. METHODS: The images were annotated by an experienced grader for the presence of iRORA and cRORA. A Resnet18 model was trained to classify these annotations for each B-scan using OCT volumes collected at the Doheny-University of California Los Angeles Eye Centers. The model was applied to 2 testing datasets to assess out-of-sample model performance. MAIN OUTCOMES MEASURES: Model performance was quantified in terms of area under the receiver operating characteristic curve (AUROC) and area under the precision-recall curve (AUPRC). Sensitivity, specificity, and positive predictive value were also compared against additional clinician annotators. RESULTS: On an independently collected test set, consisting of 1117 volumes from the general population, the model predicted iRORA and cRORA presence within the entire volume with nearly perfect AUROC performance and AUPRC scores (iRORA, 0.61; 95% confidence interval [CI] [0.45, 0.82]: cRORA, 0.83; 95% CI [0.68, 0.95]). On another independently collected set, consisting of 60 OCT B-scans enriched for iRORA and cRORA lesions, the model performed with AUROC (iRORA: 0.68, 95% CI [0.54, 0.81]; cRORA: 0.84, 95% CI [0.75, 0.94]) and AUPRC (iRORA: 0.70, 95% CI [0.55, 0.86]; cRORA: 0.82, 95% CI [0.70, 0.93]). CONCLUSIONS: A deep learning model can accurately and precisely identify both iRORA and cRORA lesions within the OCT B-scan volume. The model can achieve similar sensitivity compared with human graders, which potentially obviates a laborious and time-consuming annotation process and could be developed into a diagnostic screening tool.

Enhanced Detection of Reticular Pseudodrusen on Color Fundus Photos by Image Embossing.

PURPOSE: To evaluate whether processing a color fundus photo (CFP) using an image embossing technique can improve the detection of reticular pseudodrusen (RPD). METHODS: This post-hoc analysis included the eyes of subjects enrolled in the Amish Eye Study with early or intermediate age-related macular degeneration and evidence of RPD. All patients underwent CFP, near-infrared reflectance (NIR), and fundus autofluorescence (FAF) imaging. The ground-truth presence of RPD was established with a combination of NIR and FAF imaging. An embossing processed (EP) image was created by replacing each pixel of the CFP image with a highlight or a shadow representing light and dark boundaries in the original CFP image. The presence of RPD in CFP and EP images was assessed by two graders in a masked fashion and the sensitivity of CFP and EP for detection of RPD was evaluated. Cohen's kappa (k) was used to test inter-grader agreement for CFP and EP. RESULTS: A total of 106 eyes from 62 patients with RPDs were analyzed. The sensitivity for detection of RPD on CFP and EP was 63.2% (95%CI: 52.0%-74.4%) and 91.5% (95%CI: 85.0%-98.0%), respectively. The inter-rater reliabilities of CFP and EP for RPD detection were 0.81 and 0.84, respectively. CONCLUSIONS: Embossing of CFP can improve the sensitivity for detection of RPD. The embossing technique can be a useful tool for better assessment of the true frequency of RPD in datasets where only CFP images are available.