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    1. Characteristics of the Optic Nerve Head in Myopic Eyes Using Swept-Source Optical Coherence Tomography

      Characteristics of the Optic Nerve Head in Myopic Eyes Using Swept-Source Optical Coherence Tomography

      Purpose: To investigate the characteristics of the optic nerve head (ONH) in myopia using swept-source optical coherence tomography (SS-OCT). Methods: Participants were divided into three groups according to the axial length (AL). The optic disc morphology, retinal nerve fiber layer (RNFL) thickness, and radial peripapillary capillary (RPC) vessel density (VD), optic disc tilt, rotation, Bruch's membrane opening distance (BMOD), border length (BL), border tissue angle, focal lamina cribrosa (LC) defects, β- and γ-zone peripapillary atrophy (PPA), microvasculature dropout (MvD), choroidal thickness (CT), and the choroidal vascularity index (CVI) were compared. Linear regression analysis evaluated relationships between spherical equivalent, AL, and ...

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    2. High-Density Optical Coherence Tomography Analysis Provides Insights Into Early/Intermediate Age-Related Macular Degeneration Retinal Layer Changes

      High-Density Optical Coherence Tomography Analysis Provides Insights Into Early/Intermediate Age-Related Macular Degeneration Retinal Layer Changes

      Purpose: To topographically map all of the thickness differences in individual retinal layers between early/intermediate age-related macular degeneration (AMDearly/AMDint) and normal eyes and to determine interlayer relationships. Methods: Ninety-six AMDtotal (48 AMDearly and 48 AMDint) and 96 normal eyes from 192 participants were propensity-score matched by age, sex, and refraction. Retrospective optical coherence tomography (OCT) macular cube scans were acquired, and high-density (60 × 60 0.01-mm2) grid thicknesses were custom extracted for comparison between AMDtotal and normal eyes corrected for confounding. Resultant "normal differences" underwent cluster, interlayer correlation, and dose-response analyses for the retinal nerve fiber layer (RNFL ...

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    3. Changes in Retinal Optical Coherence Tomography Angiography Indexes Over 24 Hours

      Changes in Retinal Optical Coherence Tomography Angiography Indexes Over 24 Hours

      Purpose: To evaluate changes in the retinal microvasculature of young adults over 24 hours using optical coherence tomography angiography (OCT-A). Methods: Participants (n = 44, mean age 23.2 ± 4.1 years, 24 myopes and 20 nonmyopes) with normal ophthalmological findings were recruited. Two macular OCT-A and OCT scans, systemic blood pressure, intraocular pressure (IOP), and biometry measurements were taken every four hours over 24 hours. Superficial and deep retinal layer en face images were analyzed to extract magnification-corrected vascular indexes using image analysis including foveal avascular zone metrics, vessel density, and perfusion density for the foveal, parafoveal, and perifoveal zones ...

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    4. OCTA Derived Vessel Skeleton Density Versus Flux and Their Associations With Systemic Determinants of Health

      OCTA Derived Vessel Skeleton Density Versus Flux and Their Associations With Systemic Determinants of Health

      Purpose: To examine the associations of optical coherence tomography angiography (OCTA)-derived retinal capillary flux with systemic determinants of health. Methods: This is a cross-sectional study of subjects recruited from the African American Eye Disease Study. A commercially available swept-source (SS)-OCTA device was used to image the central 3 × 3 mm macular region. Retinal capillary perfusion was assessed using vessel skeleton density (VSD) and flux. Flux approximates the number of red blood cells moving through vessel segments and is a novel metric, whereas VSD is a previously validated measure commonly used to quantify capillary density. The associations of OCTA ...

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    5. In Vivo Sublayer Analysis of Human Retinal Inner Plexiform Layer Obtained by Visible-Light Optical Coherence Tomography

      In Vivo Sublayer Analysis of Human Retinal Inner Plexiform Layer Obtained by Visible-Light Optical Coherence Tomography

      Purpose : Growing evidence suggests that dendrite retraction or degeneration in a subpopulation of the retinal ganglion cells (RGCs) may precede detectable soma abnormalities and RGC death in glaucoma. Visualization of the lamellar structure of the inner plexiform layer (IPL) could advance clinical management and fundamental understanding of glaucoma. We investigated whether visible-light optical coherence tomography (vis-OCT) could detect the difference in the IPL sublayer thicknesses between small cohorts of healthy and glaucomatous subjects. Method : We imaged nine healthy and five glaucomatous subjects with vis-OCT. Four of the healthy subjects were scanned three times each in two separate visits, and five ...

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    6. Visual Field Sensitivity Prediction Using Optical Coherence Tomography Analysis in Hydroxychloroquine Toxicity

      Visual Field Sensitivity Prediction Using Optical Coherence Tomography Analysis in Hydroxychloroquine Toxicity

      Purpose: This study investigates the association between local retina structure and visual function in a cohort with long-term hydroxychloroquine (HCQ) use. Methods: The study included 84 participants (54 participants without toxicity and 30 participants with toxicity) with history of chronic HCQ use (14.5 ± 7.4 years) who had testing with spectral-domain optical coherence tomography (SD-OCT) imaging and Humphrey 10-2 visual fields. Optical coherence tomography (OCT) metrics (total and outer retina thickness [TRT and ORT], minimum intensity [MinI], and ellipsoid zone [EZ] loss) were sampled in regions corresponding to visual field test locations. Univariate linear correlations were investigated and a ...

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    7. Analysis of Microvasculature in Nonhuman Primate Macula With Acute Elevated Intraocular Pressure Using Optical Coherence Tomography Angiography

      Analysis of Microvasculature in Nonhuman Primate Macula With Acute Elevated Intraocular Pressure Using Optical Coherence Tomography Angiography

      Purpose: To investigate responses of macular capillary vessel area density (VAD) of superficial and deep retinal vascular plexuses to elevations in intraocular pressure (IOP) in cynomolgus macaque monkeys using optical coherence tomography angiography (OCTA). Methods: In five general anesthetized male cynomolgus monkeys, the IOP was increased incrementally by 10 mmHg from baseline (10 mmHg) to 70 mmHg and then decreased back to 10 mmHg (recovery state). Structural OCT (30° × 30°) and OCTA (20° × 15°) centered on the macula were obtained at each IOP and 3, 15, and 30 minutes after recovery. En face images of the superficial vascular complex (SVC ...

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      Mentions: Korea University
    8. Microvasculature Recovery Detected Using Optical Coherence Tomography Angiography and the Rate of Visual Field Progression After Glaucoma Surgery

      Microvasculature Recovery Detected Using Optical Coherence Tomography Angiography and the Rate of Visual Field Progression After Glaucoma Surgery

      Purpose: We evaluated microvascular changes using optical coherence tomography angiography (OCT-A) in glaucoma patients who underwent glaucoma surgery. Methods: The macula and optic nerve head were imaged using an OCT-A device at one day before surgery and at one week, one month, three months, and six months after surgery. Measurements of vessel density (VD) were made in the intradisc region and macula, and the area of the foveal avascular zone (FAZ) was measured in both superficial and deep vascular layers. A mean deviation (MD) slope value of < -1.0 decibel/y was considered to be indicative of VF progression. Results ...

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    9. Combining OCT and OCTA for Focal Structure-Function Modeling in Early Primary Open-Angle Glaucoma

      Combining OCT and OCTA for Focal Structure-Function Modeling in Early Primary Open-Angle Glaucoma

      Purpose: To investigate modeling of the focal visual field (VF) loss by combining structural measurements and vascular measurements in eyes with early primary open-angle glaucoma (POAG). Methods: In this cross-sectional study, subjects with early glaucoma (VF mean deviation, ≥-6 dB) underwent optical coherence tomography (OCT) imaging, optical coherence tomography angiography (OCTA) imaging, and Humphrey 24-2 VF tests. Capillary perfusion densities (CPDs) were calculated after the removal of large vessels in the OCTA images. Focal associations between VF losses at the individual VF test locations, circumpapillary retinal nerve fiber layer (RNFL) thickness measurements from OCT, and CPDs were determined using nerve ...

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    10. Choroidal Changes in Eyes With Polypoidal Choroidal Vasculopathy After Anti-VEGF Therapy Imaged With Swept-Source OCT Angiography

      Choroidal Changes in Eyes With Polypoidal Choroidal Vasculopathy After Anti-VEGF Therapy Imaged With Swept-Source OCT Angiography

      Purpose: Swept-source optical coherence tomography angiography was used to investigate choroidal changes and their association with pigment epithelial detachments (PEDs) in eyes with polypoidal choroidal vasculopathy (PCV) after treatment with vascular endothelial growth factor (VEGF) inhibitors. Methods: Patients with treatment-naïve PCV were included and underwent anti-VEGF therapy. Mean choroidal thickness (MCT), choroidal vascularity index (CVI), and PED volume measurements were obtained before and after treatment. Results: Thirty-four treatment-naïve PCV eyes from 33 patients were included. The PED volume decreased after treatment (P < 0.05). The MCT decreased from 223.0 ± 79.6 µm at baseline to 210.9 ...

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    11. Retinal Microcirculatory Responses to Hyperoxia in Primary Open-Angle Glaucoma Using Optical Coherence Tomography Angiography

      Retinal Microcirculatory Responses to Hyperoxia in Primary Open-Angle Glaucoma Using Optical Coherence Tomography Angiography

      Purpose: To investigate the retinal vascular response to hyperoxia in patients with primary open-angle glaucoma (POAG) using optical coherence tomography angiography (OCTA). Methods: This prospective study included 27 eyes in 27 patients with POAG and 14 eyes in 14 age- and sex-matched healthy participants. Retinal radial peripapillary capillary (RPC) perfusion was measured by OCTA before and after inhaling oxygen in all participants. Systemic hemodynamic variables were also examined and recorded before and after hyperoxia. Results: Hyperoxia significantly reduced the perfused vessel density (PVD) of RPCs in both healthy controls (baseline and hyperoxia: 54.2 ± 4.1 and 51.0 ± 4 ...

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    12. Morphometric and Microstructural Changes During Murine Retinal Development Characterized Using In Vivo Optical Coherence Tomography

      Morphometric and Microstructural Changes During Murine Retinal Development Characterized Using In Vivo Optical Coherence Tomography

      Purpose : The purpose of this study was to develop an in vivo optical coherence tomography (OCT) system capable of imaging the developing mouse retina and its associated morphometric and microstructural changes. Methods : Thirty-four wild-type mice (129S1/SvlmJ) were anesthetized and imaged between postnatal (P) day 7 and P21. OCT instrumentation was developed to optimize signal intensity and image quality. Semi-automatic segmentation tools were developed to quantify the retinal thickness of the nerve fiber layer (NFL), inner plexiform layer (IPL), inner nuclear layer (INL), and the outer retinal layers (ORL), in addition to the total retina. The retinal maturation was characterized ...

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    13. A Study of the Association Between Retinal Vessel Geometry and Optical Coherence Tomography Angiography Metrics in Diabetic Retinopathy

      A Study of the Association Between Retinal Vessel Geometry and Optical Coherence Tomography Angiography Metrics in Diabetic Retinopathy

      Purpose: The purpose of this study was to investigate whether optical coherence tomography angiography (OCTA) metrics are related to retinal vessel geometry parameters in diabetic retinopathy (DR). Methods: In total, 119 eyes (119 patients) were included in this retrospective cross-sectional study. Retinal vessel geometry parameters were analyzed using semi-automated software. OCTA metrics were analyzed using automated manufacturer-provided algorithms. Associations between the severity of DR and retinal vessel geometry parameters and OCTA metrics were evaluated. Multivariable regression analyses were performed to evaluate associations between retinal vessel geometry parameters and OCTA metrics after adjusting for clinical characteristics and DR severity. Results: DR ...

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    14. Assessment of Detailed Photoreceptor Structure and Retinal Sensitivity in Diabetic Macular Ischemia Using Adaptive Optics-OCT and Microperimetry

      Assessment of Detailed Photoreceptor Structure and Retinal Sensitivity in Diabetic Macular Ischemia Using Adaptive Optics-OCT and Microperimetry

      Purpose: The purpose of this study was to assess density and morphology of cone photoreceptors (PRs) and corresponding retinal sensitivity in ischemic compared to nonischemic retinal capillary areas of diabetic eyes using adaptive optics optical coherence tomography (AO-OCT) and microperimetry (MP). Methods: In this cross-sectional, observational study five eyes of four patients (2 eyes with proliferative diabetic retinopathy (DR) and 3 eyes moderate nonproliferative DR) were included. PR morphology and density was manually assessed in AO-OCT en face images both at the axial position of the inner-segment outer segment (IS/OS) and cone outer segment tips (COSTs). Retinal sensitivity was ...

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    15. U-Shaped Effect of Blood Pressure on Structural OCT Metrics and Retinal Perfusion in Ophthalmologically Healthy Subjects

      U-Shaped Effect of Blood Pressure on Structural OCT Metrics and Retinal Perfusion in Ophthalmologically Healthy Subjects

      Purpose: We wanted to investigate the association of blood pressure (BP) status with the ganglion cell-inner plexiform layer (GCIPL) and retinal nerve fiber layer (RNFL) thickness of nonglaucomatous eyes and to elucidate whether this effect is related to vascular metrics proxying retinal perfusion. Methods: For this case-control study, we prospectively included 96 eyes of 96 healthy subjects (age 50-65) from a large-scale population-based cohort in the northern Netherlands (n = 167,000) and allocated them to four groups (low BP, normal BP [controls], treated arterial hypertension [AHT], untreated AHT). We measured macular GCIPL and RNFL (mRNFL) and peripapillary RNFL (pRNFL) thicknesses ...

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    16. High-Speed, Long-Range Swept-Source Optical Coherence Tomography for the Anterior Segment of the Eye

      High-Speed, Long-Range Swept-Source Optical Coherence Tomography for the Anterior Segment of the Eye

      Purpose : The anterior segment (AS) of the eye is of interest in multiple diseases and procedures, including glaucoma, ocular surface inflammation, and refractive / cataract surgeries. Visualizing the anterior eye using optical coherence tomography (OCT) has unique challenges, and AS OCT technology is less developed than retinal imaging. We developed next generation swept-source OCT (SS-OCT) technology to enable high-speed and long-range AS structural and angiographic imaging in clinical settings. Methods : We designed a SS-OCT prototype instrument using wavelength-tunable, vertical-cavity surface-emitting laser (VCSEL) with linearized frequency sweep. The OCT wavelength centers at 1310 nm with a 105 nm bandwidth. The A-scan rate ...

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    17. MHz Swept Source Optical Coherence Tomography of the Choriocapillaris

      MHz Swept Source Optical Coherence Tomography of the Choriocapillaris

      Purpose : Resolving individual capillaries of the choriocapillaris with swept source optical coherence tomography (SS-OCT) angiography is challenging and has so far been limited to very small field of views (FOV). We present a MHz SS-OCT prototype, which provides high-contrast choriocapillaris (CC) images. Methods : We developed a 1060 nm SS-OCT prototype, capable of A-scan rates up to 1.7 MHz. Its lateral resolution was 7.8 μm and its axial resolution was 9 μm in tissue. We acquired Angio 12 mm x 12 mm scans with a sampling of 1024 (A-scans) x 1024 (B-scans) x 4 (B-scan repetitions) and Angio 2 ...

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    18. Hyperreflective Foci, Optical Coherence Tomography Progression Indicators in Age-Related Macular Degeneration, Include Transdifferentiated Retinal Pigment Epithelium

      Hyperreflective Foci, Optical Coherence Tomography Progression Indicators in Age-Related Macular Degeneration, Include Transdifferentiated Retinal Pigment Epithelium

      Purpose: By optical coherence tomography (OCT) imaging, hyperreflective foci (HRF) indicate progression risk for advanced age-related macular degeneration (AMD) and are in part attributable to ectopic retinal pigment epithelium (RPE). We hypothesized that ectopic RPE are molecularly distinct from in-layer cells and that their cross-retinal course follows Müller glia. Methods: In clinical OCT (61 eyes, 44 patients with AMD, 79.4 ± 7.7 years; 29 female; follow-up = 4.7 ± 0.9 years), one HRF type, RPE plume (n = 129 in 4 morphologies), was reviewed. Twenty eyes of 20 donors characterized by ex vivo OCT were analyzed by histology (normal ...

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    19. En Face Optical Coherence Tomography Imaging of Foveal Dots in Eyes With Posterior Vitreous Detachment or Internal Limiting Membrane Peeling

      En Face Optical Coherence Tomography Imaging of Foveal Dots in Eyes With Posterior Vitreous Detachment or Internal Limiting Membrane Peeling

      Purpose: To analyze the morphology of foveal hyperreflective dots (HRD) identified with en face optical coherence tomography (OCT) and evaluate the effects of internal limiting membrane (ILM) peeling and posterior vitreous detachment (PVD) on the number of these lesions. Methods: Retrospective cross-sectional study of patients with OCT angiography and en face OCT. Using en face OCT, superficial HRD lying on the foveal floor were measured and quantitated in eyes with ILM peel and in the fellow nonsurgical eyes. Eyes with foveal PVD were also compared to fellow eyes without foveal PVD. High-magnification en face OCT was also performed to better ...

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      Mentions: UCLA
    20. Macrophage-Like Cell Density Is Increased in Proliferative Diabetic Retinopathy Characterized by Optical Coherence Tomography Angiography

      Macrophage-Like Cell Density Is Increased in Proliferative Diabetic Retinopathy Characterized by Optical Coherence Tomography Angiography

      Purpose: To quantitatively characterize macrophage-like cells (MLCs) at the vitreoretinal interface in different severity stages of diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA). Methods: The study included 72 eyes of 72 subjects: 18 healthy controls, 22 diabetes mellitus (DM) without DR, 17 nonproliferative DR (NPDR), and 15 proliferative DR (PDR). We obtained repeated (average, 6.5; range, 3-10) macular OCTA scans for each eye. We registered and averaged the 3-µm OCT slab above the vitreoretinal interface to visualize MLCs. Using a semiautomated method, we binarized and quantified MLCs and compared MLC densities among groups. We also evaluated ...

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    21. Long-Term Reproducibility of Optical Coherence Tomography Angiography in Stable Glaucomatous Eyes

      Long-Term Reproducibility of Optical Coherence Tomography Angiography in Stable Glaucomatous Eyes

      Purpose : To assess and compare long-term reproducibility of optical coherence tomography angiography (OCTA) vascular parameters and spectral-domain optical coherence tomography (OCT) thickness parameters in stable glaucoma, glaucoma suspect, and healthy eyes. Methods : A total of 88 eyes (15 healthy, 38 glaucoma suspect, and 35 non-progressive POAG) of 68 subjects were enrolled who had at least 3 visits within 1 to 1.5 years and both OCT and OCTA (Optovue Inc, Fremont, California, USA) imaging on the same day. A series of vascular and thickness parameters were measured including macula whole image vessel density (wiVD), optic nerve head (ONH) circumpapillary capillary ...

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    22. Predicting central 10 degrees visual field from peripapillary optical coherence tomography using deep learning approach

      Predicting central 10 degrees visual field from peripapillary optical coherence tomography using deep learning approach

      Purpose: To develop a deep learning (DL) simulation of standard automated perimetry (SAP) in the central 10 ° based on spectral domain optical coherence tomography (SD-OCT) retinal nerve fiber layer thickness (RNFLT). Methods : This study included 5352 pairs of SD-OCT and 10-2 SAP from 1365 eyes of 724 healthy, glaucoma suspect and glaucoma patients from the Diagnostic Innovations in Glaucoma Study (DIGS) and the African Descent and Glaucoma Evaluation Study (ADAGES). Each pair of SD-OCT and 10-2 SAP was obtained within a 6-month duration. The dataset was randomly divided into training (65%), validation (15%), and test (20%) sets at the patient ...

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      Mentions: UCSD
    23. Volumetric Optical Imaging and Quantitative Analysis of Age-Related Changes in Anterior Human Vitreous

      Volumetric Optical Imaging and Quantitative Analysis of Age-Related Changes in Anterior Human Vitreous

      Purpose : The purpose of this study was to characterize age-related changes in anterior human vitreous with 3-D swept source optical coherence tomography (SS-OCT) and evaluate associations with axial length (AL) and contrast sensitivity function (CSF). Methods : There were 49 phakic eyes in 49 patients (40.0 ± 19.3 years) had 3-D volumetric scanning of the lens and retrolental vitreous with SS-OCT at 1050 nm. OCT-derived indices of vitreous optical density (VOD), vitreous opacification ratio (VOR), and lens optical density (LOD) were correlated with AL and double-pass assessment of retinal point spread function (Objective Scatter Index [OSI]). CSF was measured using ...

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    24. Swept-Source OCT Angiographic Characteristics of Treatment-Naïve Nonexudative Macular Neovascularization in AMD Prior to Exudation

      Swept-Source OCT Angiographic Characteristics of Treatment-Naïve Nonexudative Macular Neovascularization in AMD Prior to Exudation

      Purpose: To investigate the characteristics of treatment-naïve nonexudative macular neovascularization (MNV) in age-related macular degeneration before the onset of exudation using swept-source optical coherence tomography angiography. Methods: MNV area, choriocapillaris (CC) flow deficits (FDs), vessel area density (VAD), vessel skeleton density (VSD), retinal pigment epithelial detachment (PED) volume, mean choroidal thickness (MCT), and choroid vascularity index (CVI) measurements were assessed at two visits prior to exudation. We compared measurements made at the second visit and the rate of change between visits in eyes with and without exudation. The differences in these parameters between eyes with and without subsequent exudation ...

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