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    1. Optical Coherence Tomography Angiography in Papilledema Compared With Pseudopapilledema

      Optical Coherence Tomography Angiography in Papilledema Compared With Pseudopapilledema

      Purpose : The purpose of this study is to evaluate differences in optical coherence tomography angiography (OCT-A) findings between patients with papilledema and pseudopapilledema. Methods : In this prospective, comparative study, 41 eyes of 21 subjects with papilledema, 27 eyes of 15 subjects with pseudopapilledema, and 44 eyes of 44 healthy normal subjects were included and were imaged using OCT-A. In addition to peripapillary total vasculature maps obtained with commercial vessel density mapping, major vessel removal using customized image analysis software was also used to measure whole image capillary density and peripapillary capillary density (PCD). Peripapiilary retinal nerve fiber layer (RNFL) and ...

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    2. Noninvasive Assessment of Corneal Crosslinking With Phase-Decorrelation Optical Coherence Tomography

      Noninvasive Assessment of Corneal Crosslinking With Phase-Decorrelation Optical Coherence Tomography

      Purpose : There is strong evidence that abnormalities in corneal biomechanical play a causal role in corneal ectasias, such as keratoconus. Additionally, corneal crosslinking (CXL) treatment, which halts progression of keratoconus, directly appeals to corneal biomechanics. However, existing methods of corneal biomechanical assessment have various drawbacks: dependence on IOP, long acquisition times, or limited resolution. Here, we present a method that may avoid these limitations by using optical coherence tomography (OCT) to detect the endogenous random motion within the cornea, which can be associated with stromal crosslinking. Methods : Phase-decorrelation OCT (PhD-OCT), based in the theory of dynamic light scattering, is a ...

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    3. Dynamic Changes of Retinal Microaneurysms in Diabetes Imaged With In Vivo Adaptive Optics Optical Coherence Tomography

      Dynamic Changes of Retinal Microaneurysms in Diabetes Imaged With In Vivo Adaptive Optics Optical Coherence Tomography

      Purpose : To prospectively monitor microaneurysms (MAs) in three dimensions using adaptive optics optical coherence tomography (AOOCT). Methods : Patients with diabetes mellitus and parafoveal MAs were included in this longitudinal study. At baseline, MAs were identified in standard fluorescein angiography (FA) and subsequently imaged with an AOOCT prototype, incorporated into an AO fundus camera (RTX1, Imagine Eyes) device. Imaging was repeated every 3 months in each patient to explore the potential structural change of MAs over time including size, shape, intraretinal position, (intra-) luminal reflectivity, and other qualitative morphologic characteristics. Results : We imaged 18 MAs in seven eyes (two left eyes ...

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    4. Diabetic Nonperfused Areas in Macular and Extramacular Regions on Wide-Field Optical Coherence Tomography Angiography

      Diabetic Nonperfused Areas in Macular and Extramacular Regions on Wide-Field Optical Coherence Tomography Angiography

      Purpose : To investigate the nonperfused areas (NPAs) in each subfield segmented by large arterioles on wide-field swept-source optical coherence tomography angiography (SS-OCTA) images in diabetic retinopathy. Methods : We retrospectively reviewed 101 consecutive eyes of 67 patients with severe nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR), for whom 12 × 12-mm SS-OCTA images centered on the optic disc were acquired. Both eyes were included in 34 patients. NPAs in the whole retinal layers were measured in each subfield segmented by large arterioles encompassing both the superficial and deep layers. We compared the percentage of NPAs between individual subfields, considering the ...

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    5. Segmentation of the Four-Layered Retinal Vasculature Using High-Resolution Optical Coherence Tomography Angiography Reveals the Microcirculation Unit

      Segmentation of the Four-Layered Retinal Vasculature Using High-Resolution Optical Coherence Tomography Angiography Reveals the Microcirculation Unit

      Purpose : To differentiate the four layers of the retinal vessel network in the human macula and examine their morphologic features using high-resolution optical coherence tomography angiography (HR-OCTA). Methods : Macular areas measuring 464 × 464 pixels of 10 right eyes of 10 healthy subjects without ocular disease were scanned 10 times using a HR-OCTA device. Averaged OCTA images were created. Based on clear decorrelation signals, four vascular slabs were segmented, comprising one each in the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and top and bottom of the inner nuclear layer (INL). Qualitative features and quantitative measurements in each slab ...

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    6. Optical Coherence Tomography Angiography in Familial Exudative Vitreoretinopathy: Clinical Features and Phenotype-Genotype Correlatio

      Optical Coherence Tomography Angiography in Familial Exudative Vitreoretinopathy: Clinical Features and Phenotype-Genotype Correlatio

      Purpose : To evaluate the microstructure of the fovea in patients with familial exudative vitreoretinopathy (FEVR) compared to healthy controls using optical coherence tomography angiography (OCTA). Methods : In this consecutive, cross-sectional, observational case series, 41 eyes of 41 patients diagnosed as FEVR and 37 eyes in 37 control subjects were studied. OCTA was utilized to automatically measure the foveal avascular zone (FAZ) and the vessel density (VD). Inner retinal thicknesses (IRT) and central retinal thickness (CRT) were measured with the instrument caliper. Targeted next-generation sequencing was performed, and phenotype-genotype association was analyzed. Results : Small FAZ was found in 31.70% (13 ...

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    7. Mapping of Corneal Layer Thicknesses With Polarization-Sensitive Optical Coherence Tomography Using a Conical Scan Pattern

      Mapping of Corneal Layer Thicknesses With Polarization-Sensitive Optical Coherence Tomography Using a Conical Scan Pattern

      Purpose : We demonstrate segmentation and mapping of corneal layers (epithelium, Bowman's layer, and stroma) across the entire cornea (limbus to limbus), using additional contrast provided by polarization-sensitive optical coherence tomography (PS-OCT) and analyze the reproducibility of the procedure. Methods : A custom built PS-OCT system operating at 1045 nm central wavelength with conical scanning was used for image acquisition. Conical scanning allows for almost perpendicular beam incidence on the corneal surface and provides good signal quality over the entire field of view. Epithelium, Bowman's layer, and stroma were segmented using the additional contrast provided by PS-OCT. Thickness maps were ...

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    8. Author Response: Hyperreflective Intraretinal Foci as an OCT Biomarker of Retinal Inflammation in Diabetic Macular Edema

      Author Response: Hyperreflective Intraretinal Foci as an OCT Biomarker of Retinal Inflammation in Diabetic Macular Edema

      We would like to convey our gratitude to Midena et al. 1 for their thoughtful letter to the editor and their insightful comment regarding our article. 2 As shown in a previous study by Vujosevic et al., 3 the reflectivity of hyperreflective foci (HF), as aggregates of retinal microglial cells, might be lower than that of the retinal pigment epithelium (RPE) and could be similar to that of the retinal nerve fiber layer (RNFL). We also agree with the opinion that any investigation of HF regarding optical coherence tomography (OCT) in diabetic eyes should be more precise to avoid inconsistent ...

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    9. Hyperreflective Intraretinal Foci as an OCT Biomarker of Retinal Inflammation in Diabetic Macular Edema

      Hyperreflective Intraretinal Foci as an OCT Biomarker of Retinal Inflammation in Diabetic Macular Edema

      We read with great interest the article titled “Association Between Soluble CD14 in the Aqueous Humor and Hyperreflective Foci on Optical Coherence Tomography in Patients with Diabetic Macular Edema” by Lee et al. 1 The authors investigated the expression of soluble CD14 (sCD14) in aqueous humor (AH) samples of patients with diabetic macular edema (DME), and the presence of hyperreflective foci (HF) on spectral-domain optical coherence tomography (SD-OCT) in these eyes. The authors found both higher levels of sCD14, and increased number of HF in the inner retina compared to controls, and concluded that, since sCD14 is released by retinal ...

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    10. Diagnostic Capability of Three-Dimensional Macular Parameters for Glaucoma Using Optical Coherence Tomography Volume Scans

      Diagnostic Capability of Three-Dimensional Macular Parameters for Glaucoma Using Optical Coherence Tomography Volume Scans

      Purpose : To compare the diagnostic capability of three-dimensional (3D) macular parameters against traditional two-dimensional (2D) retinal nerve fiber layer (RNFL) thickness using spectral domain optical coherence tomography. To determine if manual correction and interpolation of B-scans improve the ability of 3D macular parameters to diagnose glaucoma. Methods : A total of 101 open angle glaucoma patients (29 with early glaucoma) and 57 healthy subjects had peripapillary 2D RNFL thickness and 3D macular volume scans. Four parameters were calculated for six different-sized annuli: total macular thickness (M-thickness), total macular volume (M-volume), ganglion cell complex (GCC) thickness, and GCC volume of the innermost ...

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    11. Color Fundus Image Guided Artery-Vein Differentiation in Optical Coherence Tomography Angiography

      Color Fundus Image Guided Artery-Vein Differentiation in Optical Coherence Tomography Angiography

      Purpose : This study aimed to develop a method for automated artery-vein classification in optical coherence tomography angiography (OCTA), and to verify that differential artery-vein analysis can improve the sensitivity of OCTA detection and staging of diabetic retinopathy (DR). Methods : For each patient, the color fundus image was used to guide the artery-vein differentiation in the OCTA image. Traditional mean blood vessel caliber (m-BVC) and mean blood vessel tortuosity (m-BVT) in OCTA images were quantified for control and DR groups. Artery BVC (a-BVC), vein BVC (v-BVC), artery BVT (a-BVT), and vein BVT (a-BVT) were calculated, and then the artery-vein ratio (AVR ...

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      Mentions: Xincheng Yao
    12. Longitudinal Changes of Retinal Thicknesses in Branch Retinal Artery Occlusion: Spectral-Domain Optical Coherence Tomography Study

      Longitudinal Changes of Retinal Thicknesses in Branch Retinal Artery Occlusion: Spectral-Domain Optical Coherence Tomography Study

      Purpose : To analyze longitudinal thickness changes in the overall macula, ganglion cell–inner plexiform layer (GC-IPL), and peripapillary retinal nerve fiber layer (pRNFL) using spectral-domain optical coherence tomography in branch retinal artery occlusion (BRAO). Methods : A prospective analysis was conducted in patients with BRAO. The thicknesses of the overall macula, GC-IPL, and pRNFL were measured at the initial visit, and at 1, 3, 6, and 12 months. Changes in the occluded areas of the affected and unaffected eyes were analyzed, and the nonoccluded areas were compared. Results : In the occluded areas of the affected eyes, the only overall macular thickness ...

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    13. Posterior Choroidal Stroma Reduces Accuracy of Automated Segmentation of Outer Choroidal Boundary in Swept Source Optical Coherence Tomography

      Posterior Choroidal Stroma Reduces Accuracy of Automated Segmentation of Outer Choroidal Boundary in Swept Source Optical Coherence Tomography

      Purpose : To determine the influence of choroidal boundary morphology on the accuracy of automated measurements of subfoveal choroidal thickness (SFCT) in swept source optical coherence tomography (SSOCT). Methods : A retrospective image analysis of foveal-centered horizontal line scans from normal and diseased eyes using the Topcon DRI OCT-1 Atlantis SSOCT was conducted. Subfoveal choroid-scleral junction (CSJ) and retina-choroidal junction (RCJ) morphologies were graded by two observers. Automated SFCT (A-SFCT) was compared with manual SFCT (M-SFCT) measurements from Bruch's membrane to the posterior limits of choroidal vessel, hyperreflective stroma, and hyporeflective lamina fusca. Agreement in boundary grading was assessed by Cohen ...

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    14. Statistical Model of Optical Coherence Tomography Angiography Parameters That Correlate With Severity of Diabetic Retinopathy

      Statistical Model of Optical Coherence Tomography Angiography Parameters That Correlate With Severity of Diabetic Retinopathy

      Purpose : To determine whether combining quantitative optical coherence tomography angiography (OCTA) parameters can achieve high sensitivity and specificity to distinguish eyes with nonproliferative diabetic retinopathy (NPDR) from those with proliferative diabetic retinopathy (PDR) as well as eyes with diabetes and no DR (NoDR) from those with clinical DR (any DR). Methods : This cross-sectional study included 28 eyes (17 patients) with NoDR, 54 eyes (34 patients) with NPDR, and 56 eyes (36 patients) with PDR. OCTA images were processed to quantify the foveal avascular zone (FAZ) area, acircularity, vessel density, skeletonized vessel density, fractal dimension, and intersections and average vessel diameter ...

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    15. Classification of Choroidal Neovascularization Using Projection-Resolved Optical Coherence Tomographic Angiography

      Classification of Choroidal Neovascularization Using Projection-Resolved Optical Coherence Tomographic Angiography

      Purpose : To evaluate if projection-resolved optical coherence tomographic angiography (PR-OCTA) reduces projection artifact with less attenuation of choroidal neovascularization (CNV) flow signal compared to conventional OCTA with slab subtraction. Methods : In this retrospective cross-sectional study, participants with subfoveal treatment-naïve CNV secondary to age-related macular degeneration underwent OCTA. Scans were exported for custom processing including manual segmentation as necessary, application of slab subtraction and PR-OCTA algorithm, and calculation of CNV vascular area and connectivity. CNV was classified as type 1, minimally type 2, or predominantly type 2 based on fluorescein angiography (FA) and OCT. Two masked retina specialists independently classified ...

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    16. The EYE-MI Pilot Study: A Prospective Acute Coronary Syndrome Cohort Evaluated With Retinal Optical Coherence Tomography Angiography

      The EYE-MI Pilot Study: A Prospective Acute Coronary Syndrome Cohort Evaluated With Retinal Optical Coherence Tomography Angiography

      Purpose : To evaluate the association between retinal microvasculature (vascular density) on optical coherence tomography-angiography (OCT-A) and the cardiovascular profile of patients hospitalized for acute coronary syndrome (ACS). Methods : EYE-Myocardial Infarction (EYE-MI) study is a prospective cross-sectional study in the Cardiology Intensive Care Unit of Dijon University Hospital. Retinal OCT-A was performed for each patient within 2 days after admission. Superficial retinal capillary plexus (SCP) vascular density was measured. The population was divided into tertiles according to OCT-A data. Results : Overall, 237 cases were retained for analysis. Patients in the tertile with the lowest retinal vascular density (RVD) were older, and ...

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    17. An Optical Coherence Tomography Angiography Study of the Relationship Between Foveal Avascular Zone Size and Retinal Vessel Density

      An Optical Coherence Tomography Angiography Study of the Relationship Between Foveal Avascular Zone Size and Retinal Vessel Density

      Purpose : To assess the relationship between the size of the foveal avascular zone (FAZ; area and perimeter) and vessel density (VD) at various retinal regions using optical coherence tomography angiography (OCTA) in patients with open-angle glaucoma (OAG). Methods : In this retrospective cross-sectional study, OAG eyes were grouped according to the presence/absence of central visual field (CVF) defects. A control group of normal eyes was also included. OCTA images were obtained from the optic nerve (4.5 × 4.5 mm 2 ) and macular (3 × 3 mm 2 ) area, in which VDs were measured in the circumpapilla, parafovea, and fovea regions ...

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    18. Human Parafoveal Capillary Vascular Anatomy and Connectivity Revealed by Optical Coherence Tomography Angiography

      Human Parafoveal Capillary Vascular Anatomy and Connectivity Revealed by Optical Coherence Tomography Angiography

      Purpose : To assess the connection among arterioles, venules, and capillaries in three retinal capillary plexuses using optical coherence tomography angiography (OCTA). Methods : This was a prospective, cross-sectional, observational study including 20 eyes of 10 healthy subjects. En face and cross-sectional OCTA images were segmented to study the superficial (SCP), middle (MCP), and deep capillary plexuses (DCP). Using thin slabs and manual segmentation within the three plexuses, we examined the connections between the large-caliber superficial vessels within a 3 × 3 mm 2 OCTA scan (arterioles and venules) and the smaller capillaries in each plexus. Results : Twenty eyes of 10 healthy subjects ...

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    19. Evaluation of Automated Segmentation Algorithms for Optic Nerve Head Structures in Optical Coherence Tomography Images

      Evaluation of Automated Segmentation Algorithms for Optic Nerve Head Structures in Optical Coherence Tomography Images

      Purpose : To compare the identification of optic nerve head (ONH) structures in optical coherence tomography images by observers and automated algorithms. Methods : ONH images in 24 radial scan sets by optical coherence tomography were obtained in 51 eyes of 29 glaucoma patients and suspects. Masked intraobserver and interobserver comparisons were made of marked endpoints of Bruch's membrane opening (BMO) and the anterior lamina cribrosa (LC). BMO and LC positional markings were compared between observer and automated algorithm. Repeated analysis on 20 eyes by the algorithm was compared. Regional ONH data were derived from the algorithms. Results : Intraobserver difference in ...

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    20. Macular Features on Spectral-Domain Optical Coherence Tomography Imaging Associated With Visual Acuity in Coats' Disease

      Macular Features on Spectral-Domain Optical Coherence Tomography Imaging Associated With Visual Acuity in Coats' Disease

      Purpose : To investigate the association between macular features on spectral-domain optical coherence tomography (SD-OCT) and visual acuity (VA) in Coats' disease. Methods : Thirty-nine eyes (39 patients) with SD-OCT from January 1, 2008 to December 31, 2016 were reviewed for SD-OCT features. Central subfield (CSF) SD-OCT findings were analyzed relative to VA (logarithm of the minimum angle of resolution) at baseline and final visit (when follow-up ≥ 6 months) and across visits. Results : Mean VA ± standard deviation at baseline (37 eyes) was 0.92 ± 0.82. SD-OCT features associated with worse VA included, for treatment-naïve eyes ( n = 21), outer retinal atrophy ...

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    21. Automated Diagnosis and Grading of Diabetic Retinopathy Using Optical Coherence Tomography

      Automated Diagnosis and Grading of Diabetic Retinopathy Using Optical Coherence Tomography

      Purpose : We determine the feasibility and accuracy of a computer-assisted diagnostic (CAD) system to diagnose and grade nonproliferative diabetic retinopathy (NPDR) from optical coherence tomography (OCT) images. Methods : A cross-sectional, single-center study was done of type II diabetics who presented for routine screening and/or monitoring exams. Inclusion criteria were age 18 or older, diagnosis of diabetes mellitus type II, and clear media allowing for OCT imaging. Exclusion criteria were inability to image the macula, posterior staphylomas, proliferative diabetic retinopathy, and concurrent retinovascular disease. All patients underwent a full dilated eye exam and spectral-domain OCT of a 6 × 6 mm ...

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    22. Fluorescein Leakage and Optical Coherence Tomography Features of Choroidal Neovascularization Secondary to Pathologic Myopia

      Fluorescein Leakage and Optical Coherence Tomography Features of Choroidal Neovascularization Secondary to Pathologic Myopia

      Purpose : We compare the fluorescein angiography (FA) patterns with morphologic alterations detectable on spectral-domain OCT (SD-OCT) in myopic choroidal neovascularization (mCNV) and evaluate whether they influence the effects of intravitreal ranibizumab (IVRI) in an as-needed (PRN) regimen. Methods : The 49 patients enrolled in this prospective case series underwent a complete ophthalmologic examination, including best-corrected visual acuity (BCVA), FA, and SD-OCT assessment. The main outcome measure was correlation between FA patterns and SD-OCT features. Secondary outcomes were changes in BCVA and central macular thickness (CMT), and characterization of subretinal hyperreflective exudation (SHE). Results : Three main patterns were identified on the FA ...

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    23. Error Correction and Quantitative Subanalysis of Optical Coherence Tomography Data Using Computer-Assisted Grading

      Error Correction and Quantitative Subanalysis of Optical Coherence Tomography Data Using Computer-Assisted Grading

      purpose. To demonstrate feature subanalysis and error correction of optical coherence tomography (OCT) data by using computer-assisted grading. methods. The raw exported StratusOCT (Carl Zeiss Meditec, Inc., Dublin, CA) scan data from 20 eyes of 20 patients were analyzed using custom software (termed OCTOR) designed to allow the user to define manually the retinal borders on each radial line scan. Measurements calculated by the software, including thickness of the nine standard macular subfields, foveal center point (FCP), and macular volume, were compared between two graders and with the automated Stratus analysis. Mean and range of differences for each parameter were ...

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    24. The Relationship Between Blue-Fundus Autofluorescence and Optical Coherence Tomography in Eyes With Lamellar Macular Holes

      The Relationship Between Blue-Fundus Autofluorescence and Optical Coherence Tomography in Eyes With Lamellar Macular Holes

      Purpose : The purpose of this study was to evaluate the relationship between blue-fundus autofluorescence (B-FAF) and optical coherence tomography (OCT) in eyes with lamellar macular holes (LMHs). Methods : this was a multicenter, observational case series. Ninety-two eyes with LMH associated with the standard epiretinal membrane (ERM) or lamellar hole–associated epiretinal proliferation (LHEP) were evaluated. The eyes must also present an area of increased autofluorescence on B-FAF. Results : The ERM-alone group and the LHEP group differed with respect to the following variables: logarithm of the minimum angle of resolution best-corrected visual acuity (0.13 ± 0.13 vs. 0.25 ± 0 ...

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