1. Articles from Jay S. Duker

    1-24 of 163 1 2 3 4 5 6 7 »
    1. Multiscale correlation of microvascular changes on optical coherence tomography angiography with retinal sensitivity in diabetic retinopathy

      Multiscale correlation of microvascular changes on optical coherence tomography angiography with retinal sensitivity in diabetic retinopathy

      Purpose: To assess global, zonal, and local correlations between vessel density changes measured by optical coherence tomography angiography (OCTA) and retinal sensitivity measured by microperimetry across diabetic retinopathy severity. Methods: Diabetic patients and non-diabetic controls underwent OCTA imaging and microperimetry testing. Pearson's correlation was used to assess associations between average sensitivity and skeletonized vessel density (SVD) or FAZ area centrally. Linear mixed effects modeling was used to assess relationships between local SVD measurements and their spatially corresponding retinal sensitivity measurements. Results: Thirty-nine eyes from 39 participants were imaged. In all slabs, there was a statistically significant positive correlation between ...

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    2. Anterior segment optical coherence tomography angiography in the assessment of ocular surface lesions

      Anterior segment optical coherence tomography angiography in the assessment of ocular surface lesions

      Purpose: Describe the utility of anterior segment optical coherence tomography angiography (AS-OCTA) to assess ocular surface lesions. Methods: Retrospective, case-control study of 10 eyes of 9 patients with malignant lesions and 23 eyes of 22 patients with benign lesions. Lesions included 13 epithelial, 10 pigmented and 10 lymphoid lesions. Graders performed an average of 3 depth and diameter measurements of peri-lesional vessels entering each lesion on AS-OCTA. Statistical models to assess differences between groups accounted for bilateral eye inclusion and lesion thickness (on AS-OCT). Receiver operating characteristic curve and area under the curve (AUC) were performed for each parameter. Results ...

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      Mentions: Tufts University
    3. Optical coherence tomography angiography distortion correction in widefield montage images

      Optical coherence tomography angiography distortion correction in widefield montage images

      Background: Optical coherence tomography (OCT) imaging is inherently susceptible to distortion artifacts due to the natural curvature of the eye. This study proposes a novel model for widefield OCT angiography (OCTA) distortion correction and analyzes the effects of this correction on quantification metrics. Methods: Widefield OCTA images were obtained on normal subjects at five fixation spatial positions. Radial and field distortion correction were applied and images stitched together to form a corrected widefield montage image. Vessel area density (VAD), vessel complexity index (VCI), and flow impairment area were quantified on the original and corrected montage images. Results: This model allows ...

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    4. OCT-OCTA segmentation: combining structural and blood flow information to segment Bruch's membrane

      OCT-OCTA segmentation: combining structural and blood flow information to segment Bruch's membrane

      In this paper we present a fully automated graph-based segmentation algorithm that jointly uses optical coherence tomography (OCT) and OCT angiography (OCTA) data to segment Bruch's membrane (BM). This is especially valuable in cases where the spatial correlation between BM, which is usually not visible on OCT scans, and the retinal pigment epithelium (RPE), which is often used as a surrogate for segmenting BM, is distorted by pathology. We validated the performance of our proposed algorithm against manual segmentation in a total of 18 eyes from healthy controls and patients with diabetic retinopathy (DR), non-exudative age-related macular degeneration (AMD ...

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    5. Retinal hemangioblastoma vascular detail elucidated on swept source optical coherence tomography angiography

      Retinal hemangioblastoma vascular detail elucidated on swept source optical coherence tomography angiography

      Purpose To report the distinct vascular pattern of a treatment-naïve retinal hemangioblastoma imaged on swept source optical coherence tomography angiography (SS-OCTA). Observations A 33-year-old female with a history of Von Hippel-Lindau disease presented for follow-up of bilateral retinal hemangioblastomas. Ultra-widefield fundus photography of the left eye revealed a small, juxtapapillary lesion. SS-OCTA imaging centered at the lesion identified two distinct vascular foci. Centrally, the lesion was composed of a dense capillary meshwork. Peripherally, a pattern of branching vessels with terminal budding was identified. The patient was diagnosed with a new juxtapapillary retinal hemangioblastoma. Conclusions and Importance SS-OCTA can visualize ...

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      Mentions: Tufts University
    6. Swept Source Optical Coherence Tomography Angiography in Small Choroidal Melanomas and Choroidal Nevi

      Swept Source Optical Coherence Tomography Angiography in Small Choroidal Melanomas and Choroidal Nevi

      Purpose: To evaluate the use of swept source optical coherence tomography angiography (SS-OCTA) to detect distinct vascular features in small choroidal melanomas and choroidal nevi. Methods: Patients with a choroidal nevus or a treatment-naïve choroidal melanoma were imaged with color fundus photography, ultrasound and SS-OCTA (12x12mm). High-risk features including overlying fluid, orange pigment, shaggy photoreceptors, acoustic hollowness, depth >2mm, and basal diameter >5mm were assessed. OCTA vascular markers included: choroidal vessel visualization, choroidal vessel depth, and choriocapillaris flow signal, assessed qualitatively by comparison to surrounding, unaffected choriocapillaris. Results: Twenty-nine lesions were included in this study, 7 flat choroidal nevi ...

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      Mentions: Tufts University
    7. Efficient and high accuracy 3-D OCT angiography motion correction in pathology

      Efficient and high accuracy 3-D OCT angiography motion correction in pathology

      We describe a novel method for non-rigid 3-D motion correction of orthogonally raster-scanned optical coherence tomography angiography volumes. This is the first approach that aligns predominantly axial structural features such as retinal layers as well as transverse angiographic vascular features in a joint optimization. Combined with orthogonal scanning and favorization of kinematically more plausible displacements, subpixel alignment and micrometer-scale distortion correction is achieved in all 3 dimensions. As no specific structures are segmented, the method is by design robust to pathologic changes. Furthermore, the method is designed for highly parallel implementation and short runtime, allowing its integration into clinical workflow ...

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    8. A practical guide to optical coherence tomography angiography interpretation

      A practical guide to optical coherence tomography angiography interpretation

      Background Optical coherence tomography angiography (OCTA) can image the retinal vasculature in vivo, without the need for contrast dye. This technology has been commercially available since 2014, however, much of its use has been limited to the research setting. Over time, more clinical practices have adopted OCTA imaging. While countless publications detail OCTA’s use for the study of retinal microvasculature, few studies outline OCTA’s clinical utility. Body This review provides an overview of OCTA imaging and details tips for successful interpretation. The review begins with a summary of OCTA technology and artifacts that arise from image acquisition. New ...

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      Mentions: Tufts University
    9. Anterior-segment spectral domain optical coherence tomography in epidermolysis bullosa

      Anterior-segment spectral domain optical coherence tomography in epidermolysis bullosa

      Purpose Assess epidermolysis bullosa (EB)-related corneal pathology using anterior segment optical coherence tomography (AS-OCT) and correlate imaging with clinical metrics in EB patients versus age-matched controls. Methods EB patients and controls were recruited during an EB conference (July 2018) and at Tufts Medical Center (June–August 2019). Subjects completed a questionnaire, had best corrected visual acuity (BCVA) tested, and underwent AS-OCT scanning. Stromal and epithelial thickness were measured. Depth, length, and type of the three largest lesions were assessed by a masked examiner using a novel pathology grading system. Multivariate analysis of AS-OCT findings and clinical metrics was performed ...

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      Mentions: Tufts University
    10. Repeatability of binarization thresholding methods for optical coherence tomography angiography image quantification

      Repeatability of binarization thresholding methods for optical coherence tomography angiography image quantification

      Binarization is a critical step in analysis of retinal optical coherence tomography angiography (OCTA) images, but the repeatability of metrics produced from various binarization methods has not been fully assessed. This study set out to examine the repeatability of OCTA quantification metrics produced using different binarization thresholding methods, all of which have been applied in previous studies, across multiple devices and plexuses. Successive 3 × 3 mm foveal OCTA images of 13 healthy eyes were obtained on three different devices. For each image, contrast adjustments, 3 image processing techniques (linear registration, histogram normalization, and contrast-limited adaptive histogram equalization), and 11 binarization ...

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    11. Using the Pathophysiology of Dry AMD to Guide Binarization of the Choriocapillaris on OCTA: A Model

      Using the Pathophysiology of Dry AMD to Guide Binarization of the Choriocapillaris on OCTA: A Model

      Especially since the incorporation of swept laser sources, optical coherence tomography angiography (OCTA) has enabled quantification of choriocapillaris perfusion. A critical step in this process is binarization, which makes angiographic images quantifiable in terms of perfusion metrics. It remains challenging to have confidence that choriocapillaris perfusion metrics reflect the reality of pathophysiologic flow, largely because choice of binarization method can result in significantly different perfusion metric outcomes. This commentary discusses a proof-of-concept case involving comparative assessment of binarization methods for a set of dry age-related macular degeneration OCTA data. One of these methods was deemed preferable based on superior agreement ...

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    12. The long-term effects of anti-vascular endothelial growth factor therapy on the optical coherence tomography angiographic appearance of neovascularization in age-related macular degeneration

      The long-term effects of anti-vascular endothelial growth factor therapy on the optical coherence tomography angiographic appearance of neovascularization in age-related macular degeneration

      Background The short-term effects of anti-vascular endothelial growth factor (anti-VEGF) treatment on macular neovascularization (MNV) morphology is well described, but long-term studies on morphologic changes and correlation of such changes to the type of MNV have not been conducted. This study aims to determine if different types of MNVs in neovascular AMD (nAMD) behave differently with anti-VEGF treatment as visualized on optical coherence tomography angiography (OCTA). Methods Treatment-naïve nAMD patients were retrospectively screened for baseline and follow-up OCTA imaging 10 or more months after initial treatment. Images were graded for MNV type, area, activity, mature versus immature vessels, vessel ...

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    13. Model-to-Data Approach for Deep Learning in Optical Coherence Tomography Intraretinal Fluid Segmentation

      Model-to-Data Approach for Deep Learning in Optical Coherence Tomography Intraretinal Fluid Segmentation

      Importance Amid an explosion of interest in deep learning in medicine, including within ophthalmology, concerns regarding data privacy, security, and sharing are of increasing importance. A model-to-data approach, in which the model itself is transferred rather than data, can circumvent many of these challenges but has not been previously demonstrated in ophthalmology. Objective To determine whether a model-to-data deep learning approach (ie, validation of the algorithm without any data transfer) can be applied in ophthalmology. Design, Setting, and Participants This single-center cross-sectional study included patients with active exudative age-related macular degeneration undergoing optical coherence tomography (OCT) at the New England ...

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      Mentions: Tufts University
    14. Analyzing Relative Flow Speeds in Diabetic Retinopathy Using Variable Interscan Time Analysis Optical Coherence Tomography Angiography

      Analyzing Relative Flow Speeds in Diabetic Retinopathy Using Variable Interscan Time Analysis Optical Coherence Tomography Angiography

      Objective Further insight into the flow characteristics of the vascular features associated with diabetic retinopathy (DR) may improve assessment and treatment of disease progression. The variable interscan time analysis (VISTA) algorithm is an extension of optical coherence tomography angiography (OCTA) that detects relative blood flow speeds which can then be depicted on a color-coded map. This study utilized VISTA to analyze relative blood flow speeds in the microvascular changes associated with DR. Design and Participants: In this cross-sectional study at New England Eye Center, Boston, Massachusetts, thirteen patients of varying severities of DR were enrolled. Methods OCTA images centered at ...

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    15. Morphological changes in intraretinal microvascular abnormalities after anti-VEGF therapy visualized on optical coherence tomography angiography

      Morphological changes in intraretinal microvascular abnormalities after anti-VEGF therapy visualized on optical coherence tomography angiography

      Background To examine the baseline morphological characteristics and alterations in intraretinal microvascular abnormalities (IRMAs) in response to anti-vascular endothelial growth factor (anti-VEGF) treatment, documented by optical coherence tomography angiography (OCTA) in diabetic eyes. Methods In this retrospective study, IRMAs were evaluated with multimodal imaging (fundus photography, fluorescein angiography, OCTA) in treatment-naïve diabetic eyes before and after anti-VEGF treatment for diabetic macular edema (DME) and/or proliferative diabetic retinopathy (PDR) and compared to diabetic control eyes with similar diabetic retinopathy (DR) severity that did not receive anti-VEGF therapy. The morphological characteristics of IRMAs on enface OCTA imaging were graded by ...

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    16. Repeatability and reproducibility of vessel density measurements on optical coherence tomography angiography in diabetic retinopathy

      Repeatability and reproducibility of vessel density measurements on optical coherence tomography angiography in diabetic retinopathy

      Purpose Understanding the precision of measurements on and across optical coherence tomography angiography (OCTA) devices is critical for tracking meaningful change in disease. The purpose of this study is to investigate the repeatability and reproducibility of vessel area density and vessel skeleton density measurements from various commercial OCTA devices in diabetic eyes. Methods Patients were imaged three consecutive times each on three different OCTA devices. En face OCTA images of the superficial capillary plexus, deep capillary plexus, and full retinal layer were exported for analysis. Vessel area density and vessel skeleton density were calculated. The coefficient of repeatability (CoR) was ...

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      Mentions: Tufts University
    17. Topographic analysis of macular choriocapillaris flow deficits in diabetic retinopathy using swept–source optical coherence tomography angiography

      Topographic analysis of macular choriocapillaris flow deficits in diabetic retinopathy using swept–source optical coherence tomography angiography

      Background The purpose of this study was to investigate the association between diabetic retinopathy (DR) severity and macular choriocapillaris (CC) flow deficit percentage (FD %) in different macular regions using swept-source optical coherence tomography angiography (SS-OCTA). Methods Diabetic patients with SS-OCTA images were graded by severity and retrospectively assessed. CC FD % was calculated in four different regions of the OCTA image: inner, middle, outer, and full-field region. The generalized estimating equations (GEE) approach for clustered eye data was used to determine effect size and significance of age and disease severity on FD % for each region. Results 160 eyes from 90 total ...

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    18. SPATIAL DISTRIBUTION OF CHORIOCAPILLARIS IMPAIRMENT IN EYES WITH CHOROIDAL NEOVASCULARIZATION SECONDARY TO AGE-RELATED MACULAR DEGENERATION: A Quantitative OCT Angiography Study

      SPATIAL DISTRIBUTION OF CHORIOCAPILLARIS IMPAIRMENT IN EYES WITH CHOROIDAL NEOVASCULARIZATION SECONDARY TO AGE-RELATED MACULAR DEGENERATION: A Quantitative OCT Angiography Study

      Purpose: To develop an optical coherence tomography angiography ( OCTA )-based framework for quantitatively analyzing the spatial distribution of choriocapillaris (CC) impairment around choroidal neovascularization ( CNV ) secondary to age-related macular degeneration. Methods: In a retrospective, cross-sectional study, 400-kHz swept-source OCTA images from 7 eyes of 6 patients with CNV secondary to age-related macular degeneration were quantitatively analyzed using custom software. A lesion-centered zonal OCTA analysis technique—which portioned the field-of-view into zones relative to CNV boundaries—was developed to quantify the spatial dependence of CC flow deficits. Results: Quantitative, lesion-centered zonal analysis of CC OCTA images revealed highest flow-deficit percentages near ...

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    19. How SD-OCT is enhancing our management of DR

      How SD-OCT is enhancing our management of DR

      Laser therapy was a major breakthrough in diabetic retinopathy treatment, with its efficacy validated by a number of clinical studies in the last three decades of the 20th century. However, it relied on fundus photography and fluorescein angiography to diagnose clinically significant macular edema. Since then, optical coherence tomography has revolutionized the clinical management of diabetic macular edema because of its widespread availability, ease of use, and ability to quantify DME noninvasively. This tool has become even more powerful coupled with the emergence of pharmacotherapies to treat the disease. Here, we review how OCT has changed the way retina specialists ...

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      Mentions: Tufts University
    20. A Framework for Multiscale Quantitation of Relationships Between Choriocapillaris Flow Impairment and Geographic Atrophy Growth

      A Framework for Multiscale Quantitation of Relationships Between Choriocapillaris Flow Impairment and Geographic Atrophy Growth

      Purpose To develop a multiscale analysis framework for investigating the relationships between geographic atrophy (GA) growth rate and choriocapillaris (CC) blood flow impairment using optical coherence tomography (OCT) and OCT angiography (OCTA). Design Retrospective case series. Methods We developed an OCT/OCTA analysis framework that quantitatively measures GA growth rates at global and local scales, and CC impairment at global, zonal, and local scales. A geometric GA growth model was used to measure local GA growth rates. The utility of the framework was demonstrated on 7 eyes with GA imaged at two time points using a prototype 400 kHz, 1050 ...

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    21. Global Analysis of Macular Choriocapillaris Perfusion in Dry Age-Related Macular Degeneration using Swept-Source Optical Coherence Tomography Angiography

      Global Analysis of Macular Choriocapillaris Perfusion in Dry Age-Related Macular Degeneration using Swept-Source Optical Coherence Tomography Angiography

      Purpose : Swept-source optical coherence tomography angiography (SS-OCTA) was used to investigate if the clinical stage of dry age-related macular degeneration (AMD) was correlated with global and regional macular choriocapillaris (CC) perfusion. Methods : In this retrospective, cross-sectional study, 6 × 6-mm SS-OCTA images from eyes with early, intermediate, and advanced dry AMD (56 eyes, 41 patients) were analyzed using algorithms described in the literature to assess regional flow deficit percentage (FD%) and average flow deficit size. Regions were defined by concentric areas centered on the fovea: a 1-mm-diameter area, 3-mm-diameter ring, 5-mm-diameter area, 5-mm-diameter ring, and 6 × 6-mm whole image. Data were ...

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    22. Retinal Nonperfusion Relationship to Arteries or Veins Observed on Widefield Optical Coherence Tomography Angiography in Diabetic Retinopathy

      Retinal Nonperfusion Relationship to Arteries or Veins Observed on Widefield Optical Coherence Tomography Angiography in Diabetic Retinopathy

      Purpose : To evaluate whether retinal capillary nonperfusion is found predominantly adjacent to arteries or veins in eyes with diabetic retinopathy (DR). Methods : Sixty-three eyes from 44 patients with proliferative DR (PDR) or non-PDR (NPDR) were included. Images (12 × 12-mm) foveal-centered optical coherence tomography (OCT) angiography (OCTA) images were taken using the Zeiss Plex Elite 9000. In 37 eyes, widefield montages with five fixation points were also obtained. A semiautomatic algorithm that detects nonperfusion in full-retina OCT slabs was developed, and the percentages of capillary nonperfusion within the total image area were calculated. Retinal arteries and veins were manually traced. Based ...

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    23. Controlling for Artifacts in Widefield Optical Coherence Tomography Angiography Measurements of Non-Perfusion Area

      Controlling for Artifacts in Widefield Optical Coherence Tomography Angiography Measurements of Non-Perfusion Area

      The recent clinical adoption of optical coherence tomography (OCT) angiography (OCTA) has enabled non-invasive, volumetric visualization of ocular vasculature at micron-scale resolutions. Initially limited to 3 mm × 3 mm and 6 mm × 6 mm fields-of-view (FOV), commercial OCTA systems now offer 12 mm × 12 mm, or larger, imaging fields. While larger FOVs promise a more complete visualization of retinal disease, they also introduce new challenges to the accurate and reliable interpretation of OCTA data. In particular, because of vignetting, wide-field imaging increases occurrence of low-OCT-signal artifacts, which leads to thresholding and/or segmentation artifacts, complicating OCTA analysis. This study presents ...

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    24. Impact of Binarization Thresholding and Brightness/Contrast Adjustment Methodology on Optical Coherence Tomography Angiography Image Quantification

      Impact of Binarization Thresholding and Brightness/Contrast Adjustment Methodology on Optical Coherence Tomography Angiography Image Quantification

      Purpose Binarization is a critical technique in OCTA image analysis, but there is no consistency in the method used in published OCTA studies. This study assessed whether differences in OCTA binarization and brightness/contrast adjustments affect quantification metrics. Design Prospective cross-sectional validity study Methods This was a single-center study examining 21 eyes of 11 healthy individuals. All eyes were imaged using the Carl Zeiss PLEX Elite 9000 swept source-OCTA, and quantitative metrics resulting from five binarization thresholding and five brightness/contrast adjustment methodologies were compared. All metrics were calculated for the superficial plexus and choriocapillaris (CC), as well as unaveraged ...

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      Mentions: Tufts University
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