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    1. Demographics Prediction and Heatmap Generation From OCT Images of Anterior Segment of the Eye: A Vision Transformer Model Study

      Demographics Prediction and Heatmap Generation From OCT Images of Anterior Segment of the Eye: A Vision Transformer Model Study

      Purpose: To predict demographic characteristics from anterior segment optical coherence tomography (AS-OCT) images of eyes using a Vision Transformer (ViT) model. Methods: A total of 2970 AS-OCT images were used to train, validate, and test a ViT to predict age and sex, and 2616 images were used for height, weight, and body mass index (BMI). The main outcome measure was the area under the receiver operating characteristic curve (AUC) of the ViT. Results: The ViT achieved the largest AUC (0.910) for differentiating age ≤75 versus >75 years, followed by age ≤60 versus 60-75 versus >75 years (AUC, 0.844 ...

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    2. Iris Color Matters-A Contractility Analysis With Dynamic Volume-Rendered Optical Coherence Tomography Pupillometry

      Iris Color Matters-A Contractility Analysis With Dynamic Volume-Rendered Optical Coherence Tomography Pupillometry

      Purpose: To analyze natural variability in pupillary contractility with dynamic volume-rendered optical coherence tomography (OCT) pupillometry regarding iris color, age, and sex in healthy Caucasian participants. Methods: The intrapupillary spaces (IPSs) derived from anterior segment swept-source OCT of 71 healthy eyes were retrospectively analyzed. Baseline scotopic and photopic volumes and the functional parameters of pupillary ejection fraction (PEF), three-dimensional (3D) contractility, and relative light response (RLR) were measured on the swept-source OCT volumes. The effect on these parameters of iris color (brown, green, and blue), age, and sex was assessed. Results: More pigmented irises were more contractile than less pigmented ...

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    3. Early Assessment of Circumferential Anterior Segment Structures Following Implantable Collamer Lens V4c Implantation Via SS-OCT

      Early Assessment of Circumferential Anterior Segment Structures Following Implantable Collamer Lens V4c Implantation Via SS-OCT

      Purpose: To explore early changes in circumferential anterior segment structures following Implantable Collamer Lens (ICL) V4c implantation via swept-source optical coherence tomography (SS-OCT). Methods: In 103 eyes of 56 myopic patients undergoing ICL V4c surgery, anterior segments were measured via SS-OCT to compute local anterior chamber angle (ACA) parameters on the nasal-temporal (0°-180°), superior-inferior (90°-270°), and superior nasal-inferior temporal (80°-260°) meridians, including angle-opening distance at 500 µm (AOD500), trabecular-iris space area at 500 µm (TISA500), trabecular-iris angle at 500 µm (TIA500), and circumferential ACA parameters, including AOD area at 500 µm (AODA500), trabecular-iris circumference volume at 500 ...

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    4. Degeneration of Melanin-Containing Structures Observed Longitudinally in the Eyes of SOD1-/- Mice Using Intensity, Polarization, and Spectroscopic OCT

      Degeneration of Melanin-Containing Structures Observed Longitudinally in the Eyes of SOD1-/- Mice Using Intensity, Polarization, and Spectroscopic OCT

      Purpose: Melanin plays an important function in maintaining eye health, however there are few metrics that can be used to study retinal melanin content in vivo. Methods: The slope of the spectral coefficient of variation (SSCoV) is a novel biomarker that measures chromophore concentration by analyzing the local divergence of spectral intensities using optical coherence tomography (OCT). This metric was validated in a phantom and applied in a longitudinal study of superoxide dismutase 1 knockout (SOD1-/-) mice, a model for wet and dry age-related macular degeneration. We also examined a new feature of interest in standard OCT image data, the ...

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    5. Application of Deep Learning for Automated Detection of Polypoidal Choroidal Vasculopathy in Spectral Domain Optical Coherence Tomography

      Application of Deep Learning for Automated Detection of Polypoidal Choroidal Vasculopathy in Spectral Domain Optical Coherence Tomography

      Objective: To develop an automated polypoidal choroidal vasculopathy (PCV) screening model to distinguish PCV from wet age-related macular degeneration (wet AMD). Methods: A retrospective review of spectral domain optical coherence tomography (SD-OCT) images was undertaken. The included SD-OCT images were classified into two distinct categories (PCV or wet AMD) prior to the development of the PCV screening model. The automated detection of PCV using the developed model was compared with the results of gold-standard fundus fluorescein angiography and indocyanine green (FFA + ICG) angiography. A framework of SHapley Additive exPlanations was used to interpret the results from the model. Results: A ...

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    6. Glaucoma Diagnostic Performance of Retinal Blood Flow Measurement With Doppler Optical Coherence Tomography

      Glaucoma Diagnostic Performance of Retinal Blood Flow Measurement With Doppler Optical Coherence Tomography

      Purpose: The purpose of this study was to evaluate the diagnostic performance of retinal blood flow (RBF) measured with the Doppler optical coherence tomography (OCT) segmental scanning method to distinguish between healthy and glaucoma eyes. Methods: Fifty-eight patients with normal tension glaucoma (NTG) who had a single-hemifield visual field defect and 44 age-matched healthy subjects were enrolled. Retinal nerve fiber layer thickness (RNFLT) was measured with swept-source OCT. Superior and inferior temporal arteries (TAs) and temporal veins (TVs) RBF were measured with Doppler OCT. The area under the curve (AUC) of the receiver operating characteristic (ROC) was used to compare ...

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    7. Synthetic OCT Data Generation to Enhance the Performance of Diagnostic Models for Neurodegenerative Diseases

      Synthetic OCT Data Generation to Enhance the Performance of Diagnostic Models for Neurodegenerative Diseases

      Purpose: Optical coherence tomography (OCT) has recently emerged as a source for powerful biomarkers in neurodegenerative diseases such as multiple sclerosis (MS) and neuromyelitis optica (NMO). The application of machine learning techniques to the analysis of OCT data has enabled automatic extraction of information with potential to aid the timely diagnosis of neurodegenerative diseases. These algorithms require large amounts of labeled data, but few such OCT data sets are available now. Methods: To address this challenge, here we propose a synthetic data generation method yielding a tailored augmentation of three-dimensional (3D) OCT data and preserving differences between control and disease ...

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    8. Measurement of the Macular Hole Diameter by En Face Slab Optical Coherence Tomography Reflectance Imaging

      Measurement of the Macular Hole Diameter by En Face Slab Optical Coherence Tomography Reflectance Imaging

      Purpose: To evaluate the repeatability of macular hole (MH) diameter measurement on en face slab optical coherence tomography (OCT) reflectance images and assess its potential to predict visual acuity (VA). Methods: We enrolled 27 eyes with full-thickness MHs in this study. Preoperative en face slab OCT reflectance images were obtained. Image binarization, ellipse approximation, and uncorrected measurement of minimum diameter, min(ef_uc), and maximum diameter, max(ef_uc), were performed using ImageJ. In addition, magnification-corrected diameters were calculated as min(ef) and max(ef) using the Littman and modified Bennett formulas. Spectral-domain OCT horizontal images were used as the conventional method ...

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    9. Etiology of Macular Edema Defined by Deep Learning in Optical Coherence Tomography Scans

      Etiology of Macular Edema Defined by Deep Learning in Optical Coherence Tomography Scans

      Purpose: To develop an automated method based on deep learning (DL) to classify macular edema (ME) from the evaluation of optical coherence tomography (OCT) scans. Methods: A total of 4230 images were obtained from data repositories of patients attended in an ophthalmology clinic in Colombia and two free open-access databases. They were annotated with four biomarkers (BMs) as intraretinal fluid, subretinal fluid, hyperreflective foci/tissue, and drusen. Then the scans were labeled as control or ocular disease among diabetic macular edema (DME), neovascular age-related macular degeneration (nAMD), and retinal vein occlusion (RVO) by two expert ophthalmologists. Our method was developed ...

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    10. Visible Light Optical Coherence Tomography of Peripapillary Retinal Nerve Fiber Layer Reflectivity in Glaucoma

      Visible Light Optical Coherence Tomography of Peripapillary Retinal Nerve Fiber Layer Reflectivity in Glaucoma

      Purpose: To evaluate the clinical utility of visible light optical coherence tomography (VIS-OCT) and to test whether VIS-OCT reflectivity and spectroscopy of peripapillary retinal nerve fiber layer (pRNFL) are correlated with severity of glaucoma, compared with standard-of-care OCT thickness measurements. Methods: In total 54 eyes (20 normal, 17 suspect/preperimetric glaucoma [GS/PPG], 17 perimetric glaucoma [PG]) were successfully imaged with complete datasets. All the eyes were scanned by a custom-designed dual-channel device that simultaneously acquired VIS-OCT and near-infrared OCT (NIR-OCT) images. A 5 × 5 mm2 scan was taken of the pRNFL. The pRNFL reflectivity was calculated for both channels ...

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    11. Feasibility of Automated Segmentation of Pigmented Choroidal Lesions in OCT Data With Deep Learning

      Feasibility of Automated Segmentation of Pigmented Choroidal Lesions in OCT Data With Deep Learning

      Purpose: To evaluate the feasibility of automated segmentation of pigmented choroidal lesions (PCLs) in optical coherence tomography (OCT) data and compare the performance of different deep neural networks. Methods: Swept-source OCT image volumes were annotated pixel-wise for PCLs and background. Three deep neural network architectures were applied to the data: the multi-dimensional gated recurrent units (MD-GRU), the V-Net, and the nnU-Net. The nnU-Net was used to compare the performance of two-dimensional (2D) versus three-dimensional (3D) predictions. Results: A total of 121 OCT volumes were analyzed (100 normal and 21 PCLs). Automated PCL segmentations were successful with all neural networks. The ...

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    12. Clinical Correlation Between Optical Coherence Tomography Biomarkers and Retinal Sensitivity in Best Vitelliform Macular Dystrophy

      Clinical Correlation Between Optical Coherence Tomography Biomarkers and Retinal Sensitivity in Best Vitelliform Macular Dystrophy

      Purpose: To investigate the clinical and imaging features associated with retinal sensitivity in Best vitelliform macular dystrophy (BVMD). Methods: This was a cross-sectional, single-center, observational study. Each patient underwent optical coherence tomography (OCT), near-infrared fundus autofluorescence, and OCT angiography. Macular integrity assessment microperimetry under mesopic conditions was performed to obtain retinal sensitivity thresholds from 68 testing points in the central macula. Structural OCT was used to classify BVMD lesions into four types according to their composition: vitelliform, mixed, subretinal fluid, and atrophy. Multilevel, mixed-effects linear regression was used to determine the factors associated with retinal sensitivity. Results: The study included ...

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    13. Hyperreflective Membrane at the Vitreoretinal Interface in Diabetic Macular Edema: A Finding in Ultra-High-Resolution Optical Coherence Tomography

      Hyperreflective Membrane at the Vitreoretinal Interface in Diabetic Macular Edema: A Finding in Ultra-High-Resolution Optical Coherence Tomography

      Purpose: Detecting subtle vitreoretinal interface (VRI) findings, such as a posterior hyaloid membrane, is difficult with conventional retinal imaging. We compared ultra-high-resolution spectral domain optical coherence tomography (UHR-SD-OCT) with standard-resolution OCT (SD-OCT) for the imaging of VRI abnormalities in diabetic retinopathy (DR). Methods: This prospective cross-sectional study included 113 consecutive patients (91 patients with diabetes and 22 healthy controls). The VRI was evaluated, and the results were compared between the conventional SD-OCT and UHR-SD-OCT images. VRI findings were also investigated before and after internal limiting membrane peeling during vitrectomy for proliferative DR. Results: A total of 159 eyes (87.4 ...

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    14. Biological Correlations and Confounders for Quantification of Retinal Ganglion Cells by Optical Coherence Tomography Based on Studies of Outbred Mice

      Biological Correlations and Confounders for Quantification of Retinal Ganglion Cells by Optical Coherence Tomography Based on Studies of Outbred Mice

      Purpose: Despite popularity of optical coherence tomography (OCT) in glaucoma studies, it's unclear how well OCT-derived metrics compare to traditional measures of retinal ganglion cell (RGC) abundance. Here, Diversity Outbred (J:DO) mice are used to directly compare ganglion cell complex (GCC) thickness measured by OCT to metrics of retinal anatomy measured ex vivo with retinal wholemounts and optic nerve histology. Methods: J:DO mice (n = 48) underwent fundoscopic and OCT examinations, with automated segmentation of GCC thickness. RGC axons were quantified from para-phenylenediamine-stained optic nerve cross-sections and somas from BRN3A-immunolabeled retinal wholemounts, with total inner retinal cellularity assessed ...

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    15. A Metascore of Multiple Imaging Methods to Measure Long-Term Glaucoma Structural Progression

      A Metascore of Multiple Imaging Methods to Measure Long-Term Glaucoma Structural Progression

      Purpose : To develop a structural metascore (SMS) that combines measurements from different devices and expresses them on a single scale to facilitate their long-term analysis. Methods : Three structural measurements (Heidelberg Retina Tomograph II [HRT] rim area, HD-Cirrus optical coherence tomography [OCT] average retinal nerve fiber layer [RNFL] thickness, Spectralis OCT RNFL global thickness) were normalized on a scale of 0 to 100 and converted to a reference value. The resultant metascores were plotted against time. SMS performance was evaluated to predict future values (internal validation), and correlations between the average grades assigned by three clinicians were compared with the SMS ...

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      Mentions: UCLA
    16. Regression-Based Strategies to Reduce Refractive Error-Associated Glaucoma Diagnostic Bias When Using OCT and OCT Angiography

      Regression-Based Strategies to Reduce Refractive Error-Associated Glaucoma Diagnostic Bias When Using OCT and OCT Angiography

      Purpose : The purpose of this study was to correct refractive error-associated bias in optical coherence tomography (OCT) and OCT angiography (OCTA) glaucoma diagnostic parameters. Methods : OCT and OCTA imaging were obtained from participants in the Hong Kong FAMILY cohort. The Avanti/AngioVue OCT/OCTA system was used to measure the peripapillary nerve fiber layer thickness (NFLT), peripapillary nerve fiber layer plexus capillary density (NFLP-CD), macular ganglion cell complex thickness (GCCT), and macular superficial vascular complex vascular density (SVC-VD). Healthy eyes, including ones with axial ametropia, were enrolled for analysis. Results : A total of 1346 eyes from 792 participants were divided ...

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    17. The Impact of Image Processing Algorithms on Optical Coherence Tomography Angiography Metrics and Study Conclusions in Diabetic Retinopathy

      The Impact of Image Processing Algorithms on Optical Coherence Tomography Angiography Metrics and Study Conclusions in Diabetic Retinopathy

      Purpose: The purpose of this study was to evaluate the impact of image processing on quantitative metrics in optical coherence tomography angiography (OCTA) images and study conclusions in patients with diabetes. Methods: This was a single center, retrospective cross-sectional study. OCTA imaging with the Cirrus HD-OCT 5000 AngioPlex of patients with diabetes was performed. The 8 × 8 mm superficial slab images underwent 4 different preprocessing methods (none, background subtraction [BGS], foveal avascular zone brightness adjustment, and contrast limited adaptive histogram equalization [CLAHE]) followed by 4 different binarization algorithms (global Huang, global Otsu, local Niblack, and local Phansalkar) in ImageJ. Vessel ...

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      Mentions: Yale University
    18. Visible Light Optical Coherence Tomography Reveals the Relationship of the Myoid and Ellipsoid to Band 2 in Humans

      Visible Light Optical Coherence Tomography Reveals the Relationship of the Myoid and Ellipsoid to Band 2 in Humans

      Purpose: We employ visible light optical coherence tomography (OCT) to investigate the relationship between the myoid, ellipsoid, and band 2 in the living human retina. Rather than refute existing theories, we aim to reveal new bands and better delineate the structures at hand. Methods: An upgraded spectral/Fourier domain visible light OCT prototype, with 1.0-µm axial resolution, imaged 13 eyes of 13 young adult human subjects (23-40 years old) without a history of ocular pathology. The external limiting membrane (band 1) and band 2 edges were segmented. Reflectivity was examined along the inner segment (IS), defined as extending ...

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    19. Development of Cumulative Order-Preserving Image Transformation Based Variational Autoencoder for Anterior Segment Optical Coherence Tomography Images

      Development of Cumulative Order-Preserving Image Transformation Based Variational Autoencoder for Anterior Segment Optical Coherence Tomography Images

      Purpose: To develop a variational autoencoder (VAE) suitable for analysis of the latent structure of anterior segment optical coherence tomography (AS-OCT) images and to investigate possibilities of latent structure analysis of the AS-OCT images. Methods: We retrospectively collected clinical data and AS-OCT images from 2111 eyes of 1261 participants from the ongoing Asan Glaucoma Progression Study. A specifically modified VAE was used to extract six symmetrical and one asymmetrical latent variable. A total of 1692 eyes of 1007 patients were used for training the model. Conventional measurements and latent variables were compared between 74 primary angle closure (PAC) and 51 ...

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    20. Pointwise Visual Field Estimation From Optical Coherence Tomography in Glaucoma Using Deep Learning

      Pointwise Visual Field Estimation From Optical Coherence Tomography in Glaucoma Using Deep Learning

      Purpose : Standard automated perimetry is the gold standard to monitor visual field (VF) loss in glaucoma management, but it is prone to intrasubject variability. We trained and validated a customized deep learning (DL) regression model with Xception backbone that estimates pointwise and overall VF sensitivity from unsegmented optical coherence tomography (OCT) scans. Methods : DL regression models have been trained with four imaging modalities (circumpapillary OCT at 3.5 mm, 4.1 mm, and 4.7 mm diameter) and scanning laser ophthalmoscopy en face images to estimate mean deviation (MD) and 52 threshold values. This retrospective study used data from patients ...

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      Mentions: K. U. Leuven
    21. In Vivo Imaging of Retinal and Choroidal Morphology and Vascular Plexuses of Vertebrates Using Swept-Source Optical Coherence Tomography

      In Vivo Imaging of Retinal and Choroidal Morphology and Vascular Plexuses of Vertebrates Using Swept-Source Optical Coherence Tomography

      Purpose: To perform in vivo evaluation of the structural morphology and vascular plexuses of the neurosensory retina and choroid across vertebrate species using swept-source optical coherence tomography (SS-OCT) and SS-OCT angiography (SS-OCTA) imaging. Methods: A custom-built SS-OCT system with an incorporated flexible imaging arm was used to acquire the three-dimensional (3D) retinal OCT and vascular OCTA data of five different vertebrates: a mouse (C57BL/6J), a rat (Long Evans), a gray short-tailed opossum (Monodelphis domestica), a white sturgeon (Acipenser transmontanus), and a great horned owl (Bubo virginianus). Results: In vivo structural morphology of the retina and choroid, as well as ...

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    22. Widefield OCT Imaging for Quantifying Inner Retinal Thickness in the Nonhuman Primate

      Widefield OCT Imaging for Quantifying Inner Retinal Thickness in the Nonhuman Primate

      Purpose: To determine the agreement and repeatability of inner retinal thickness measures from widefield imaging compared to standard scans in healthy nonhuman primates. Methods: Optical coherence tomography (OCT) scans were acquired from 30 healthy rhesus monkeys, with 11 animals scanned at multiple visits. The scan protocol included 20° × 20° raster scans centered on the macula and optic nerve head (ONH), a 12° diameter circular scan centered on the ONH, and a 55 × 45° widefield raster scan. Each scan was segmented using custom neural network-based algorithms. Bland-Altman analysis were used for comparing average circumpapillary retinal nerve fiber layer (RNFL) thickness and ...

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    23. Retinal Microvasculature and Choriocapillaris Flow Deficit in Relation to Serum Uric Acid Using Swept-Source Optical Coherence Tomography Angiography

      Retinal Microvasculature and Choriocapillaris Flow Deficit in Relation to Serum Uric Acid Using Swept-Source Optical Coherence Tomography Angiography

      Purpose: To explore the relationship between serum uric acid (SUA) and retinochoroidal microcirculation in the Chinese population. Methods: This prospective cross-sectional study was conducted among the residents of Guangzhou, southern China. A commercially available optical coherence tomography angiography (OCTA) device was used to obtain the superficial vessel density (SVD) and deep vessel density in the retina and the choriocapillaris flow deficit (CFD) in the macular region. Univariable and multivariable linear regression models were used to assess the association of hyperuricemia and SUA levels with OCTA parameters. Results: A total of 638 participants with normal SUA and 296 participants with hyperuricemia ...

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    24. Real-Time Risk Score for Glaucoma Mass Screening by Spectral Domain Optical Coherence Tomography: Development and Validation

      Real-Time Risk Score for Glaucoma Mass Screening by Spectral Domain Optical Coherence Tomography: Development and Validation

      Purpose: To develop and validate a risk score assessable in real-time using only retinal thickness-related values measured by spectral domain optical coherence tomography alone for use in population-based glaucoma mass screenings. Methods: A total of 7572 participants (aged 35-74 years) underwent spectral domain optical coherence tomography examination annually between 2016 to 2021 in a population-based setting. We selected 284 glaucoma cases and 284 controls, matched by age and sex, from 11,487 scans in 2016. We conducted multivariable logistic regression with backward stepwise selection of retinal thickness-related variables to develop the diagnostic models. The developed risk scores were applied to ...

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