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    1. 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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    2. The Relationship Between Ambient Atmospheric Fine Particulate Matter (PM2.5) and Glaucoma in a Large Community Cohort

      The Relationship Between Ambient Atmospheric Fine Particulate Matter (PM2.5) and Glaucoma in a Large Community Cohort

      Purpose : Glaucoma is more common in urban populations than in others. Ninety percent of the world's population are exposed to air pollution above World Health Organization (WHO) recommended limits. Few studies have examined the association between air pollution and glaucoma. Methods : Questionnaire data, ophthalmic measures, and ambient residential area air quality data for 111,370 UK Biobank participants were analyzed. Particulate matter with an aerodynamic diameter < 2.5 μm (PM 2.5 ) was selected as the air quality exposure of interest. Eye measures included self-reported glaucoma, intraocular pressure (IOP), and average thickness of macular ganglion cell–inner plexiform layer ...

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    3. Retinal and Choroidal Perfusion Status in the Area of Laser Scars Assessed With Swept-Source Optical Coherence Tomography Angiography

      Retinal and Choroidal Perfusion Status in the Area of Laser Scars Assessed With Swept-Source Optical Coherence Tomography Angiography

      Purpose : To evaluate the perfusion status of the retina and choriocapillaris in the area of laser scars on swept-source optical coherence tomography angiography (OCTA) images of eyes previously treated with panretinal photocoagulation (PRP). Methods : Cross-sectional exploratory analysis of swept-source OCTA images, which were retrospectively reviewed for laser scars. The appearance of the capillary networks in the area of previous laser were evaluated following a three-step grading system (normal/sparse/missing capillary network). The superficial and deep capillary plexus of the retina and the choriocapillaris were graded separately. Results : A total of 3140 laser scars in 54 eyes of 31 patients ...

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    4. Characteristics of Posterior Precortical Vitreous Pockets and Cloquet's Canal in Patients with Myopia by Swept-Source Optical Coherence Tomography

      Characteristics of Posterior Precortical Vitreous Pockets and Cloquet's Canal in Patients with Myopia by Swept-Source Optical Coherence Tomography

      Purpose : To describe the morphological features of posterior precortical vitreous pockets (PPVP) and Cloquet's Canal in patients with myopia using swept-source optical coherence tomography (SS OCT). Methods : A total of 96 eyes of 51 volunteers (range, 5–18 years) were enrolled in this study, and all individuals underwent OCT (Optovue Inc., Fremont, CA, USA) examinations. From the collected PPVPs images, the widths and heights of the PPVPs were measured, and connections between PPVPs and Cloquet's Canal were identified. The PPVPs widths and heights, width:height ratios and proportions of connections were compared among different age (5–8, 9 ...

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    5. Macular Vessel Density Measured With Optical Coherence Tomography Angiography and Its Associations in a Large Population-Based Study

      Macular Vessel Density Measured With Optical Coherence Tomography Angiography and Its Associations in a Large Population-Based Study

      Purpose : We investigate macular perfusion and the systemic and ocular associations in a population-based setting. Methods : In this cross-sectional study, 2018 adults residing in Hong Kong underwent detailed ophthalmic examinations after consenting to participate. Macular perfusion was measured with optical coherence tomography angiography (OCTA) using the split-spectrum amplitude decorrelation angiography algorithm. The parafoveal flow index and vessel area density were quantified using automated custom-built software. Results : Of the 2018 participants, the OCTA measurements were available for 1940, and 1631 (84.1%) had good quality scans. The right eyes of these 1631 participants (43.1% men) were included for final analysis ...

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    6. Association Between Perifoveal Drusen Burden Determined by OCT and Genetic Risk in Early and Intermediate Age-Related Macular Degeneration

      Association Between Perifoveal Drusen Burden Determined by OCT and Genetic Risk in Early and Intermediate Age-Related Macular Degeneration

      Purpose : The purpose of this study was to determine associations between macular drusen parameters derived from an automatic optical coherence tomography (OCT) algorithm, nonadvanced age-related macular degeneration (AMD) stage, and genetic variants. Methods : Eyes classified as early or intermediate AMD with OCT imaging and genetic data were selected ( n = 239 eyes). Drusen area and volume measurements were estimated using the Zeiss Cirrus advanced retinal pigment epithelium analysis algorithm in a perifoveal zone centered on the fovea. Associations between drusen measurements and common genetic variants in the complement and high-density lipoprotein (HDL) lipid pathways and the ARMS2/HTRA1 variant were calculated ...

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    7. Analysis of Hyperreflective Dots Within the Central Fovea in Healthy Eyes Using En Face Optical Coherence Tomography

      Analysis of Hyperreflective Dots Within the Central Fovea in Healthy Eyes Using En Face Optical Coherence Tomography

      Purpose : The purpose of this retrospective study was to describe and quantify superficial hyperreflective dots within the central fovea and correlate them with age, using en face and cross-sectional B-scan optical coherence tomography (OCT). Methods : Healthy eyes, evaluated with a spectral domain instrument (primary cohort) at the Stein Eye Institute (UCLA) and with a swept source instrument (secondary cohort) at the Vitreous Retina Macula Consultants of New York, were included in this study. En face OCT images (3 × 3 mm) segmented at the level of the superior vascular plexus were acquired, and hyperreflective dots in the foveal avascular zone were ...

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    8. 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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    9. Effect of Choroidal Vessel Density on the Ellipsoid Zone and Visual Function in Retinitis Pigmentosa Using Optical Coherence Tomography Angiography

      Effect of Choroidal Vessel Density on the Ellipsoid Zone and Visual Function in Retinitis Pigmentosa Using Optical Coherence Tomography Angiography

      Purpose : We evaluate the effect of choroidal vessel density on the residual length of the ellipsoid zone (EZ) and visual function in patients with retinitis pigmentosa (RP) using optical coherence tomography angiography (OCTA). Methods : Fifty-three patients with RP ( n = 101 eyes) and 53 normal participants ( n = 76 eyes) were enrolled in this study. Patients with RP were assigned to three groups according to their best-corrected visual acuity (BCVA). All patients underwent ophthalmologic examinations, including BCVA, fundus examination performed with a slit-lamp using an indirect 90 diopter (D) lens, OCTA, full-field electroretinogram (ERG), and visual field. The choroidal vessel density in ...

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    10. Histologic Correlation of Pig Retina Radial Stratification with Ultrahigh-Resolution Optical Coherence Tomography

      Histologic Correlation of Pig Retina Radial Stratification with Ultrahigh-Resolution Optical Coherence Tomography

      purpose. To compare ultrahigh-resolution optical coherence tomography (OCT) cross-sectional images of the pig retina with histology, to evaluate the potential of ultrahigh-resolution OCT for enhanced visualization of intra- and subretinal structures. methods. Ultrahigh-resolution OCT images were acquired with 1.4-μm axial × 3-μm transverse resolution from in vitro posterior eyecup preparations of the domestic pig. Frozen sections were obtained in precise alignment with OCT tomograms, by using major blood vessels as orientation markers and were counterstained with cresyl violet or unstained and examined by differential interference contrast microscopy. Micrographs from histologic sections were linearly scaled to correct for tissue ...

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    11. A Pilot Optical Coherence Tomography Angiography Study on Superficial and Deep Capillary Plexus Foveal Avascular Zone in Patients With Beta-Thalassemia Major

      A Pilot Optical Coherence Tomography Angiography Study on Superficial and Deep Capillary Plexus Foveal Avascular Zone in Patients With Beta-Thalassemia Major

      Purpose : To investigate foveal avascular zone (FAZ) changes in the superficial (SCP) and deep (DCP) capillary plexuses in beta-thalassemia major (BTM) patients, as shown in optical coherence tomography angiography. Methods : Nonrandomized, comparative case series of 54 eyes of 27 BTM patients and 46 eyes of 23 healthy controls, utilizing an automated FAZ detection algorithm. Measurements included FAZ area and FAZ shape descriptors (convexity, circularity, and contour temperature). Results were compared between the two groups, and correlated to iron load and chelation therapy parameters. Results : SCP and DCP FAZ area were not significantly different between the control and BTM groups ( P ...

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    12. Relations Among Corneal Curvature, Thickness, and Volume in Keratoconus as Evaluated by Anterior Segment–Optical Coherence Tomography

      Relations Among Corneal Curvature, Thickness, and Volume in Keratoconus as Evaluated by Anterior Segment–Optical Coherence Tomography

      Purpose : To provide insight into the mechanism underlying corneal deformation in keratoconus, we examined the relations among corneal curvature, thickness, and volume as well as the association of corneal scar formation with these parameters. Methods : A total of 288 corneas of 174 keratoconus patients and 114 corneas of 57 control subjects were examined by anterior segment–optical coherence tomography (AS-OCT). Anterior and posterior refractive values, corneal thickness (CT), and corneal volume (CV) were determined by AS-OCT for both control and keratoconic eyes. The pattern of corneal stromal scarring was also determined from the AS-OCT images. Results : The distribution of CV ...

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    13. Association of Body Fluid Expansion With Optical Coherence Tomography Measurements in Diabetic Retinopathy and Diabetic Macular Edema

      Association of Body Fluid Expansion With Optical Coherence Tomography Measurements in Diabetic Retinopathy and Diabetic Macular Edema

      Purpose : To evaluate associations of body fluid status with optical coherence tomography measurements in patients with diabetic retinopathy (DR). Methods : This prospective, cross-sectional study enrolled a total of 104 eyes from 104 patients with diabetes mellitus for fundus evaluations of DR and optical coherence tomography examinations. DR severity was graded via fundus photography. Systemic body fluid status was recorded via a body composition monitor with output values of total body water, extracellular water (ECW), intracellular water, and overhydration (OH). Relative overhydration (ROH) was defined as OH/ECW. Volume overload was defined as ROH ≥7%. Correlations of central subfield thickness (CST ...

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    14. Effects of Age on Peripapillary and Macular Vessel Density Determined Using Optical Coherence Tomography Angiography in Healthy Eyes

      Effects of Age on Peripapillary and Macular Vessel Density Determined Using Optical Coherence Tomography Angiography in Healthy Eyes

      Purpose : To evaluate the effect of age on global and sectoral vascular parameters of the peripapillary area and macula in healthy eyes by using optical coherence tomography angiography (OCT-A). Methods : This retrospective cross-sectional study included 239 eyes of 172 healthy subjects. Subjects were scanned using the high-definition disc angio scan (4.5 × 4.5 mm), retina angio scan (6 × 6 mm), and optic nerve head/ganglion cell complex (GCC) modes of OCT-A. Global and sectoral circumpapillary vessel density (VD), parafoveal VD, retinal nerve fiber layer (RNFL), and GCC thickness parameters were modeled in terms of age by using linear mixed-effect ...

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    15. Comparison of Retinal Microvasculature in Patients With Alzheimer's Disease and Primary Open-Angle Glaucoma by Optical Coherence Tomography Angiography

      Comparison of Retinal Microvasculature in Patients With Alzheimer's Disease and Primary Open-Angle Glaucoma by Optical Coherence Tomography Angiography

      Purpose : Comparison of retinal microvasculature within the macula and the optic nerve head in the eyes of patients with Alzheimer's disease (AD), primary open-angle glaucoma (POAG), and in a healthy control (HC) group, using optical coherence tomography angiography (OCTA). Methods : In this cross-sectional study, 27 patients with AD, 27 with POAG, and 27 healthy controls were enrolled. The Mini-Mental State Examination test was used to assess cognitive function. Ophthalmic examination included OCTA, which was used for the imaging of vascular flow within the layer of radial peripapillary capillaries (RPCs), and also in the superficial vascular plexus (SVP) and deep ...

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    16. Interspecies Variation of Outer Retina and Choriocapillaris Imaged With Optical Coherence Tomography

      Interspecies Variation of Outer Retina and Choriocapillaris Imaged With Optical Coherence Tomography

      Purpose : The purpose of this study is to assess with spectral-domain optical coherence tomography (OCT) the interspecies variation of outer retinal morphology and identification of choriocapillaris in four research animal species. Methods : Spectralis HRA+OCT images acquired from locations dorsal, central, and ventral to the optic disc in healthy, anesthetized animals were evaluated by two independent readers. First, the number of OCT B-scans on which a choriocapillaris layer could clearly be identified was determined and quantified, and B-scans were correlated with histology. Second, B-scans demonstrating the highest number of discernable individual outer retinal bands (ORBs) were defined as ideal presentation ...

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    17. Volumetric Analysis of Vascularized Serous Pigment Epithelial Detachment Progression in Neovascular Age-Related Macular Degeneration Using Optical Coherence Tomography Angiography

      Volumetric Analysis of Vascularized Serous Pigment Epithelial Detachment Progression in Neovascular Age-Related Macular Degeneration Using Optical Coherence Tomography Angiography

      Purpose : To analyze the evolution of type 1 neovascularization associated with vascularized serous pigment epithelial detachment (vsPED) using three-dimensional, volumetric, en face optical coherence tomography angiography (OCTA). Methods : This was a retrospective case series from four tertiary medical centers. OCTA images were analyzed at baseline and at the 3-, 6-, 12-, 18-, and 24-month follow-up visit when available. Visual acuity, number of injections, PED maximal height and PED area and volume, and choroidal neovascularization (CNV) flow area and progression were determined at each visit. Qualitative and quantitative analysis of CNV progression (including CNV/PED flow area) and final PED morphology ...

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    18. Evaluation of Retinal Pigment Epithelium Layer Change in Vogt-Koyanagi-Harada Disease With Multicontrast Optical Coherence Tomography

      Evaluation of Retinal Pigment Epithelium Layer Change in Vogt-Koyanagi-Harada Disease With Multicontrast Optical Coherence Tomography

      Purpose : Clinical evaluation of retinal pigment epithelium (RPE) change is important for the therapeutic management of chronic Vogt-Koyanagi-Harada (VKH) disease. We evaluated long-term change in the RPE layer in VKH disease, using near-infrared (NIR; 817 nm) images and autofluorescence images at 488 nm (short-wavelength [SW]-AF) and 785 nm (NIR-AF), and compared those images with images from multicontrast optical coherence tomography (MC-OCT). MC-OCT is capable of simultaneous measurement of OCT angiography, polarization-sensitive OCT, and standard OCT. Methods : We evaluated 24 eyes of 12 patients with chronic VKH disease. RPE changes were assessed using NIR, NIR-AF, SW-AF, and MC-OCT imaging performed ...

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    19. Retinal Vascular Changes During Pregnancy Detected With Optical Coherence Tomography Angiograph

      Retinal Vascular Changes During Pregnancy Detected With Optical Coherence Tomography Angiograph

      Purpose : To evaluate retinal vascular status during pregnancy by using optical coherence tomography angiography (OCTA). Methods : Women in their third trimester of pregnancy and nonpregnant age-matched women were recruited for this prospective, case-control study. Subjects were imaged with OCTA. Main outcome measures were foveal avascular zone parameters, perfusion density (PD) percentage in the superficial retinal capillary plexus (SCP), PD percentage in the deep retinal capillary plexus (DCP), SCP vessel length density (VLD), DCP-VLD, and choriocapillaris (CC) flow voids (i.e., flow deficits in the CC). Results : Nineteen eyes of 10 pregnant subjects and 44 eyes of 27 nonpregnant control women ...

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    20. Regional Differences of Choroidal Structure Determined by Wide-Field Optical Coherence Tomography

      Regional Differences of Choroidal Structure Determined by Wide-Field Optical Coherence Tomography

      Purpose : To compare the submacular to the perimacular choroidal structure in images obtained by wide-field optical coherence tomography (OCT). Methods : Thirty eyes of 30 healthy volunteers (15 men) were studied. Twelve wide-field radial circumferential scans were recorded with enhanced depth imaging OCT from the macular and perimacular zones. The sizes of the luminal and stromal areas of the choroid were determined. The two zones were subdivided into the superior, inferior, nasal, and temporal sectors. The total choroidal area, the luminal and stromal areas, and the luminal ratio of each sector were compared. Results : All of the choroidal structural parameters analyzed ...

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    21. Impaired Retinal Vascular Reactivity in Diabetic Retinopathy as Assessed by Optical Coherence Tomography Angiography

      Impaired Retinal Vascular Reactivity in Diabetic Retinopathy as Assessed by Optical Coherence Tomography Angiography

      Purpose : To assess retinal vascular reactivity in healthy controls and subjects with diabetic retinopathy (DR). Methods : A total of 22 healthy control eyes and 16 eyes with DR were enrolled. Images were acquired using a commercially available swept-source optical coherence tomography angiography (SS-OCTA) system. Three conditions were tested for each patient (hyperoxia, hypercapnia, and room-air) by employing a non-rebreathing apparatus that delivered appropriate gas mixtures (100% O 2 , 5% CO 2 , room air). Vessel skeleton density (VSD) and vessel diameter index (VDI) were compared between the conditions using mixed-model ANOVA adjusting for age and hypertension. Significant gas or interaction effects ...

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    22. Impact of Posterior Sclera on Glaucoma Progression in Treated Myopic Normal-Tension Glaucoma Using Reconstructed Optical Coherence Tomographic Images

      Impact of Posterior Sclera on Glaucoma Progression in Treated Myopic Normal-Tension Glaucoma Using Reconstructed Optical Coherence Tomographic Images

      Purpose : To investigate factors associated with visual field (VF) progression in treated myopic normal-tension glaucoma (NTG) using a novel posterior sclera reconstruction method involving swept-source optical coherence tomography (OCT). Methods : Fifty-six myopic patients on ocular hypotensive therapy with the diagnose NTG had five or more VF tests during a period of 72.63 ± 20.46 months in clinical follow-up. Glaucomatous VF progression was decided by the standards of Early Manifest Glaucoma Trial criteria. Coronally reconstructed OCT images were used to obtain the position of the deepest point of the eye (DPE), and parameterized the distance (Disc-DPE distance), depth (Disc–DPE ...

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    23. Air-Puff-Induced Dynamics of Ocular Components Measured with Optical Biometry

      Air-Puff-Induced Dynamics of Ocular Components Measured with Optical Biometry

      Purpose : To analyze the dynamics of all optical components of the eye and the behavior of the eyeball under air-puff conditions in vivo. To determine the impact of the intraocular pressure (IOP) on the air-puff-induced deformation of the eye. Methods : Twenty eyes of 20 healthy subjects were included in this study. The dynamics of the ocular components, such as the cornea, the crystalline lens, and the retina, was measured by a prototype swept source optical coherence tomography biometer integrated with the air-puff system. The system allows to acquire a series of axial scans at the same location as a function ...

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    24. Peripapillary and Macular Vessel Density in Dysthyroid Optic Neuropathy: An Optical Coherence Tomography Angiography Study

      Peripapillary and Macular Vessel Density in Dysthyroid Optic Neuropathy: An Optical Coherence Tomography Angiography Study

      Purpose : To evaluate peripapillary and macular vessel density in eyes with dysthyroid optic neuropathy (DON) and its correlation with visual function. Methods : Patients diagnosed as thyroid-associated ophthalmopathy (TAO) with or without DON and healthy participants were recruited. All subjects underwent a complete ophthalmic examination and optical coherence tomography angiography centered on the fovea and the optic nerve head. Microvascular measurements were summarized as vessel density in the whole image and in each subfield. Visual function, including best-corrected visual acuity (BCVA), visual field (VF), and visual evoked potential (VEP), were assessed for all TAO patients. Areas under the receiver operating characteristic ...

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