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    1. Relative Postpartum Retinal Vasoconstriction Detected With Optical Coherence Tomography Angiography

      Relative Postpartum Retinal Vasoconstriction Detected With Optical Coherence Tomography Angiography

      Purpose : To characterize changes in retinal perfusion during pregnancy and the postpartum period using optical coherence tomography angiography (OCTA). Methods : A nonmydriatic OCTA camera was used to image healthy women who were pregnant or in the postpartum period along with nonpregnant controls. Perfusion density (PD) and vessel length density (VLD) in the superficial capillary plexus (SCP), intermediate capillary plexus (ICP), and deep capillary plexus (DCP) were evaluated. Results : A total of 16, 15, and 13 eyes from nonpregnant, pregnant, and healthy postpartum subjects, respectively, were evaluated. When compared to controls, there were significant increases in ICP PD during the second ...

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    2. Choroidal Thickness by Handheld Swept-Source Optical Coherence Tomography in Term Newborns

      Choroidal Thickness by Handheld Swept-Source Optical Coherence Tomography in Term Newborns

      Purpose : To describe normative values for choroidal thickness in newborns and characterize their relationship to vitreoretinal features. Methods : Term newborns underwent awake, handheld swept-source optical coherence tomography (SS-OCT) in this prospective cohort study. An automated segmentation algorithm followed by manual adjustments measured choroidal thickness at the fovea and five perifoveal locations. Two masked, trained graders, with a third mediating disagreements, analyzed scans for vitreoretinal findings. OCT vitreoretinal findings, including dome-shaped macula, subretinal fluid, punctate hyperreflective vitreous opacities, persistent inner retinal layers, foveal ellipsoid zone, tractional and non-tractional vitreous bands, epiretinal membrane, cystoid macular edema, vessel elevation, scalloped retinal layers, hyporeflective ...

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    3. Three-Dimensional Distribution Of Fundus Depolarization and Associating Factors Measured Using Polarization-Sensitive Optical Coherence Tomography

      Three-Dimensional Distribution Of Fundus Depolarization and Associating Factors Measured Using Polarization-Sensitive Optical Coherence Tomography

      Purpose : To investigate the three-dimensional distribution and associating demographic factors of depolarization, using polarization-sensitive optical coherence tomography (PS-OCT), to evaluate melanin pigmentation in the retinal pigment epithelium (RPE) and choroid in healthy eyes. Methods : In total, 39 unaffected healthy eyes of 39 subjects were examined using a PS-OCT clinical prototype. The degree of depolarization, expressed as the polarimetric entropy, was assessed in the RPE, the superficial and the total choroid layer, especially in the center, the inner, or the outer areas centered at the fovea. The values and their association with the demographic data were analyzed. Near-infrared fundus autofluorescence (NIRAF ...

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    4. A Wide-Field Optical Coherence Tomography Normative Database Considering the Fovea-Disc Relationship for Glaucoma Detection

      A Wide-Field Optical Coherence Tomography Normative Database Considering the Fovea-Disc Relationship for Glaucoma Detection

      Purpose : One purpose of this study was to collect wide-field swept-source optical coherence tomography (SS-OCT) data from healthy eyes and build a wide-filed normative database. Another purpose was to compare the glaucoma diagnostic ability of new parameters based on this normative database to the parameters that are currently in use, such as the peripapillary retinal nerve fiber layer (RNFL), macular ganglion cell-inner plexiform layer, and ganglion cell complex (GCC) thickness. Methods : This study had 220 healthy eyes and 292 eyes with early-stage glaucoma (EG) and moderate-stage glaucoma (MG) enrolled. Using the wide-field SS-OCT images (12 × 9 mm) of healthy eyes ...

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    5. Wide-Field Swept-Source Optical Coherence Tomography Angiography Analysis of the Periarterial Capillary-Free Zone in Branch Retinal Vein Occlusion

      Wide-Field Swept-Source Optical Coherence Tomography Angiography Analysis of the Periarterial Capillary-Free Zone in Branch Retinal Vein Occlusion

      Purpose : To investigate the characteristics of the retinal periarterial capillary-free zone (paCFZ) with wide-field swept-source optical coherence tomography angiography (SS-OCTA) in eyes with branch retinal vein occlusion (BRVO). Methods : Seventy treatment-naïve eyes with BRVO and 35 healthy eyes were included. The paCFZ areas, artery calibers, and areas of the major arteries in the unaffected quadrants of BRVO eyes were measured in 12 × 12-mm SS-OCTA images and compared with those of the contralateral eyes and healthy eyes. Other multimodal imaging data were collected. Results : There were no significant differences in the unaffected artery caliber or area among the three groups ...

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      Mentions: Fudan University
    6. Use of the Retinal Vascular Histology to Validate an Optical Coherence Tomography Angiography Technique

      Use of the Retinal Vascular Histology to Validate an Optical Coherence Tomography Angiography Technique

      Purpose: To determine the fidelity of optical coherence tomography angiography (OCTA) techniques by direct comparison of the retinal capillary network images obtained from the same region as imaged by OCTA and high-resolution confocal microscope. Method: Ten porcine eyes were perfused with red blood cells for OCTA image acquisition from the area centralis and then perfusion-fixed, and the vessels were labeled for confocal imaging. Two approaches involving post-processing of two-dimensional projection images and vessel tracking on three dimensional image stacks were used to obtain quantitative measurements. Data collected include vessel density, length of visible vessel track, count of visible branch points ...

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    7. Intra- and Intergrader Agreement for Detection of OCT Angiographic Characteristics Associated With Type 3 Neovascularization

      Intra- and Intergrader Agreement for Detection of OCT Angiographic Characteristics Associated With Type 3 Neovascularization

      Purpose: To examine the intra- and intergrader agreement on morphologic characteristics of type 3 neovascularization on optical coherence tomography angiography (OCT-A). Methods: OCT-A images of 22 eyes from 21 patients with a new-onset, treatment-naive type 3 neovascularization were included in this cross-sectional retrospective agreement study. Each image was graded three times by two independent medical retina specialists to assess intra- and intergrader agreement. The graders scored the presence or absence of the following vascular and structural features: intraretinal neovascularization (IRN), subretinal neovascularization, sub-retinal pigment epithelium (RPE) neovascularization (SRPEN), retinal choroidal anastomosis (RCA), intraretinal cysts, subretinal fluid, and pigment epithelial detachment ...

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    8. Hints for Gentle Submacular Injection in Non-Human Primates Based on Intraoperative OCT Guidance

      Hints for Gentle Submacular Injection in Non-Human Primates Based on Intraoperative OCT Guidance

      Purpose: Delivery of Advanced Therapy Medicinal Products to the submacular space is increasingly evolving into a therapeutic modality. Cell replacement for age-related macular degeneration (AMD) and gene therapy for RPE65 are recent successful examples. Herein, a nonhuman primate (NHP) model was used to investigate surgical means to detach the macula. Methods: Sixteen eyes of 13 healthy macaques underwent a 25-gauge vitrectomy and subretinal injection of balanced salt solution monitored by microscope-integrated intraoperative optical coherence tomography (miOCT). The animals were followed with OCT and histology. Results: The miOCT monitoring allowed a more precise definition of surgical trauma ranging from an initial ...

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    9. Evaluation of Automated Multiclass Fluid Segmentation in Optical Coherence Tomography Images Using the Pegasus Fluid Segmentation Algorithms

      Evaluation of Automated Multiclass Fluid Segmentation in Optical Coherence Tomography Images Using the Pegasus Fluid Segmentation Algorithms

      Purpose : To evaluate the performance of the Pegasus-OCT (Visulytix Ltd) multiclass automated fluid segmentation algorithms on independent spectral domain optical coherence tomography data sets. Methods : The Pegasus automated fluid segmentation algorithms were applied to three data sets with edematous pathology, comprising 750, 600, and 110 b-scans, respectively. Intraretinal fluid (IRF), sub-retinal fluid (SRF), and pigment epithelial detachment (PED) were automatically segmented by Pegasus-OCT for each b-scan where ground truth from data set owners was available. Detection performance was assessed by calculating sensitivities and specificities, while Dice coefficients were used to assess agreement between the segmentation methods. Results : For two data ...

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    10. Deep Learning for Anterior Segment Optical Coherence Tomography to Predict the Presence of Plateau Iris

      Deep Learning for Anterior Segment Optical Coherence Tomography to Predict the Presence of Plateau Iris

      Purpose : The purpose of this study was to evaluate the diagnostic performance of deep learning (DL) anterior segment optical coherence tomography (AS-OCT) as a plateau iris prediction model. Design : We used a cross-sectional study of the development and validation of the DL system. Methods : We conducted a collaboration between a referral eye center and an informative technology department. The study enrolled 179 eyes from 142 patients with primary angle closure disease (PACD). All patients had remaining appositional angle after iridotomy. Each eye was scanned in four quadrants for both AS-OCT and ultrasound biomicroscopy (UBM). A DL algorithm for plateau iris ...

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    11. Optical Coherence Tomography Artifacts Are Associated With Adaptive Optics Scanning Light Ophthalmoscopy Success in Achromatopsia

      Optical Coherence Tomography Artifacts Are Associated With Adaptive Optics Scanning Light Ophthalmoscopy Success in Achromatopsia

      Purpose : To determine whether artifacts in optical coherence tomography (OCT) images are associated with the success or failure of adaptive optics scanning light ophthalmoscopy (AOSLO) imaging in subjects with achromatopsia (ACHM). Methods : Previously acquired OCT and non-confocal, split-detector AOSLO images from one eye of 66 subjects with genetically confirmed achromatopsia (15 CNGA3 and 51 CNGB3 ) were reviewed along with best-corrected visual acuity (BCVA) and axial length. OCT artifacts in interpolated vertical volumes from CIRRUS macular cubes were divided into four categories: (1) none or minimal, (2) clear and low frequency, (3) low amplitude and high frequency, and (4) high amplitude ...

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    12. Predicting Age From Optical Coherence Tomography Scans With Deep Learning

      Predicting Age From Optical Coherence Tomography Scans With Deep Learning

      Purpose : To assess whether age can be predicted from deep learning analysis of peripapillary spectral-domain optical coherence tomography (SD-OCT) B-scans and to determine the importance of specific retinal areas on the predictions. Methods : Deep learning (DL) convolutional neural networks were developed to predict chronological age in healthy subjects using peripapillary SD-OCT B-scan images. Models were built using the whole B-scan, as well as using specific regions through image ablation. Cross-validation was used for training and testing the model. Mean absolute error (MAE) and correlations between predicted and observed age were used to evaluate model performance. Results : A total of 7271 ...

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      Mentions: Duke University
    13. Optical Path Redirection Device for Optical Coherence Tomography Angiography of Recumbent Patients Under General Anesthesia

      Optical Path Redirection Device for Optical Coherence Tomography Angiography of Recumbent Patients Under General Anesthesia

      Purpose : Optical coherence tomography angiography is useful for the noninvasive imaging of retinal and choroidal vasculature, but some patients are unable to cooperate for imaging in clinic. We created a device that allows for imaging in the recumbent position under anesthesia. Methods : A three-dimensional printed prototype was designed to attach to the Optovue AngioVue. Within the device, a right-angled mirror was positioned to redirect the optical path of the optical coherence tomography angiography machine downward into the eye of a recumbent, intubated patient. Results : Three image sequences were successfully performed using the first test device. The image clarity was adequate ...

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      Mentions: Optovue
    14. Correlation of Visual Field With Peripapillary Vessel Density Through Optical Coherence Tomography Angiography in Normal-Tension Glaucoma

      Correlation of Visual Field With Peripapillary Vessel Density Through Optical Coherence Tomography Angiography in Normal-Tension Glaucoma

      Purpose : To investigate the retinal vessel density (VD) in healthy and normal-tension glaucoma (NTG) eyes through optical coherence tomography angiography (OCTA) and to determine the correlation between VD and the retinal nerve fiber layer (RNFL) thickness and functional visual field (VF) defects for different locations. Methods : A total of 74 NTG eyes and 24 healthy eyes were included. OCTA VD at 4.5 × 4.5 mm peripapillary region and 3.0 × 3.0 mm macula area, RNFL thickness, and VF pattern deviation results were individually analyzed on the basis of the Garway-Heath sectorization. Correlations between VD and VF/RNFL and ...

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    15. DeepRetina: Layer Segmentation of Retina in OCT Images Using Deep Learning

      DeepRetina: Layer Segmentation of Retina in OCT Images Using Deep Learning

      Purpose: To automate the segmentation of retinal layers, we propose DeepRetina, a method based on deep neural networks. Methods: DeepRetina uses the improved Xception65 to extract and learn the characteristics of retinal layers. The Xception65-extracted feature maps are inputted to an atrous spatial pyramid pooling module to obtain multiscale feature information. This information is then recovered to capture clearer retinal layer boundaries in the encoder-decoder module, thus completing retinal layer auto-segmentation of the retinal optical coherence tomography (OCT) images. Results: We validated this method using a retinal OCT image database containing 280 volumes (40 B-scans per volume) to demonstrate its ...

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    16. Quantitative Handheld Swept-Source Optical Coherence Tomography Angiography in Awake Preterm and Full-Term Infants

      Quantitative Handheld Swept-Source Optical Coherence Tomography Angiography in Awake Preterm and Full-Term Infants

      Purpose : To compare retinal vascular parameters acquired by handheld swept-source optical coherence tomography angiography (SS-OCTA) between nonsedated preterm and full-term infants. Methods : Preterm and full-term infants at the University of Washington Medical Center were enrolled. Retinal angiograms (nominal size ∼7 × 7 mm 2 ) were obtained at each routine retinopathy of prematurity (ROP) screening session for preterms and once during the first 72 hours of life for full-terms. Macular vessel area density and nonperfusion area were evaluated on the binarized vasculature map in both small (1.5 × 1.5 mm) and large (3 × 3 mm) quadrants. Average vessel diameter and tortuosity ...

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    17. Maternal Optical Coherence Tomography Angiography Changes Related to Small for Gestational Age Pregnancies

      Maternal Optical Coherence Tomography Angiography Changes Related to Small for Gestational Age Pregnancies

      Purpose : To study maternal retinal changes in pregnancies that resulted in a small for gestational age (SGA) infant. Methods : Pregnant women with SGA infants at birth and age-matched pregnant women with appropriate for gestational age (AGA) infants at birth (controls) were enrolled. All subjects underwent spectral domain optical coherent tomography angiography (OCTA) imaging using a 10° × 10° scan pattern centered on the fovea. Vessel density (VD) and vessel length density (VLD) of the superficial capillary plexus (SCP), intermediate capillary plexus (ICP), and deep capillary plexus (DCP) were analyzed and compared between the two groups. Results : Twelve eyes of eight subjects ...

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    18. Automated Segmentation of Optical Coherence Tomography Angiography Images: Benchmark Data and Clinically Relevant Metrics

      Automated Segmentation of Optical Coherence Tomography Angiography Images: Benchmark Data and Clinically Relevant Metrics

      Purpose : To generate the first open dataset of retinal parafoveal optical coherence tomography angiography (OCTA) images with associated ground truth manual segmentations, and to establish a standard for OCTA image segmentation by surveying a broad range of state-of-the-art vessel enhancement and binarization procedures. Methods : Handcrafted filters and neural network architectures were used to perform vessel enhancement. Thresholding methods and machine learning approaches were applied to obtain the final binarization. Evaluation was performed by using pixelwise metrics and newly proposed topological metrics. Finally, we compare the error in the computation of clinically relevant vascular network metrics (e.g., foveal avascular zone ...

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    19. Using OCT Fixation Shift to Assess Eccentric Fixation in Children With Residual Amblyopia

      Using OCT Fixation Shift to Assess Eccentric Fixation in Children With Residual Amblyopia

      Purpose : Eccentric fixation in amblyopia is often estimated grossly without precision. Although the usefulness of optical coherence tomography (OCT) fixation shift in the quantification of eccentric fixation in a small cohort of amblyopic children was recently reported, there is a lack of understanding of characteristics of OCT fixation shift. In a retrospective cohort study, we evaluated eccentric fixation with OCT in a large cohort of children with residual amblyopia. Methods : Children, age 4 to 17 years, with residual amblyopia (amblyopic, n = 56) and without amblyopia (control, n = 75) were enrolled. Amblyopia was associated with anisometropia alone (anisometropia subtype, n = 28 ...

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    20. OCTA Multilayer and Multisector Peripapillary Microvascular Modeling for Diagnosing and Staging of Glaucoma

      OCTA Multilayer and Multisector Peripapillary Microvascular Modeling for Diagnosing and Staging of Glaucoma

      Purpose: To develop and assess an automatic procedure for classifying and staging glaucomatous vascular damage based on optical coherence tomography angiography (OCTA) imaging. Methods: OCTA scans (Zeiss Cirrus 5000 HD-OCT) from a random eye of 39 healthy subjects and 82 glaucoma patients were used to develop a new classification algorithm based on multilayer and multisector information. The averaged circumpapillary retinal nerve fiber layer (RNFL) thickness was also collected. Three models, support vector machine (SVM), random forest (RF), and gradient boosting (xGB), were developed and optimized for classifying between healthy and glaucoma patients, primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG ...

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    21. Combined Multi-Modal Assessment of Glaucomatous Damage With Electroretinography and Optical Coherence Tomography/Angiography

      Combined Multi-Modal Assessment of Glaucomatous Damage With Electroretinography and Optical Coherence Tomography/Angiography

      Abstract Purpose : To compare the diagnostic performance and to evaluate the interrelationship of electroretinographical and structural and vascular measures in glaucoma. Methods : For 14 eyes of 14 healthy controls and 15 eyes of 12 patients with glaucoma ranging from preperimetric to advanced stages optical coherence tomography (OCT), OCT-angiography (OCT-A), and electrophysiological measures (multifocal photopic negative response ratio [mfPhNR] and steady-state pattern electroretinography [ssPERG]) were applied to assess changes in retinal structure, microvasculature, and function, respectively. The diagnostic performance was assessed via area-under-curve (AUC) measures obtained from receiver operating characteristics analyses. The interrelation of the different measures was assessed with correlation ...

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    22. Improved Automated Foveal Avascular Zone Measurement in Cirrus Optical Coherence Tomography Angiography Using the Level Sets Macro

      Improved Automated Foveal Avascular Zone Measurement in Cirrus Optical Coherence Tomography Angiography Using the Level Sets Macro

      Purpose : To evaluate automated measurements of the foveal avascular zone (FAZ) using the Level Sets macro (LSM) in ImageJ as compared with the Cirrus optical coherence tomography angiography (OCTA) inbuilt algorithm and the Kanno–Saitama macro (KSM). Methods : The eyes of healthy volunteers were scanned four times consecutively on the Zeiss Cirrus HD-OCT 5000 system. The FAZ metrics (area, perimeter, and circularity) were measured manually and automatically by the Cirrus inbuilt algorithm, the KSM, and the LSM. The accuracy and repeatability of all methods and agreement between automated and manual methods were evaluated. Results : The LSM segmented the FAZ with ...

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    23. Pathological-Corneas Layer Segmentation and Thickness Measurement in OCT Images

      Pathological-Corneas Layer Segmentation and Thickness Measurement in OCT Images

      Purpose : The purpose of this study was to propose a new algorithm for the segmentation and thickness measurement of pathological corneas with irregular layers using a two-stage graph search and ray tracing. Methods : In the first stage, a graph, with only gradient edge-cost, is used to segment the air-epithelium and endothelium-aqueous boundaries. In the second stage, a graph, with gradient, directional, and multiplier edge-cost, is used to correct segmentation. The optical coherence tomography (OCT) image is flattened using the air-epithelium boundary and a graph search is used to segment the epithelium-Bowman's and Bowman's-stroma boundaries. Then, the OCT image ...

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    24. A Novel Approach to Quantitative Evaluation of Outer Retinal Lesions Via a New Parameter “Integral” in Spectral Domain Optical Coherence Tomography

      A Novel Approach to Quantitative Evaluation of Outer Retinal Lesions Via a New Parameter “Integral” in Spectral Domain Optical Coherence Tomography

      Purpose : The purpose of this study was to design a new parameter “integral” to quantitatively evaluate the spatial cumulative reflectivity of the outer retinal layers in optical coherence tomography (OCT), and to investigate its role in the detection of outer retinal diseases. Methods : This was a cross-sectional study. Fovea-centered line OCT scans were performed on 60 eyes of 60 healthy volunteers and 44 eyes of 44 patients diagnosed with outer retinal diseases. The integrals of the ellipsoid zone (EZ) and interdigitation zone (IZ) were measured by respectively accumulating the grayscale values of all the pixels within the EZ and IZ ...

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      Mentions: Fudan University
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