1. 1-24 of 348 1 2 3 4 ... 13 14 15 »
    1. 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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    2. 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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    3. 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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    4. 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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    5. 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
    6. 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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    7. 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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    8. 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
    9. 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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    10. 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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    11. Relationship Between Optical Coherence Tomography Parameter and Visual Function in Eyes With Epiretinal Membrane

      Relationship Between Optical Coherence Tomography Parameter and Visual Function in Eyes With Epiretinal Membrane

      Purpose: To investigate the associations between visual function and the optical coherence tomography (OCT) parameters in eyes with idiopathic epiretinal membrane (ERM). Methods: Thirty-nine consecutive eyes with ERM were enrolled. In addition to OCT parameters, such as central retinal thickness (CRT), the area of gap between the ERM and the retinal surface (SUKIMA) was newly defined and calculated from the vertical and horizontal OCT images (SUKIMAv and SUKIMAh). The average of SUKIMAv and SUKIMAh (SUKIMAave) was used for the statistical analysis. The vertical and horizontal metamorphopsia scores (MV, MH) and the average of MV and MH (Mave) were also used ...

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    12. Parafoveal Microvascular Alterations in Ocular and Non-Ocular Behҫet's Disease Evaluated With Optical Coherence Tomography Angiography

      Parafoveal Microvascular Alterations in Ocular and Non-Ocular Behҫet's Disease Evaluated With Optical Coherence Tomography Angiography

      Purpose: To compare quantitative optical coherence tomography angiography (OCT-A) measurements of the parafoveal microvasculature in retinal capillary plexuses among Behҫet uveitis (BU) patients, non-ocular Behҫet's disease (NOBD) patients, and healthy volunteers (HVs). Methods: Sixty-eight subjects were enrolled in this prospective observational cross-sectional study. OCT-A imaging was performed using the Heidelberg Engineering Spectralis OCT. A custom algorithm was developed to calculate the vessel density (VD) in three retinal vascular layers: deep capillary plexus, intermediate capillary plexus, and superficial vascular plexus. The foveal avascular zone (FAZ) and acircularity index were calculated for the whole retinal vascular complex. Results: We analyzed one ...

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    13. Wide-Field Swept-Source Optical Coherence Tomography Analysis of Interocular Symmetry of Choroidal Thickness in Healthy Young Individuals

      Wide-Field Swept-Source Optical Coherence Tomography Analysis of Interocular Symmetry of Choroidal Thickness in Healthy Young Individuals

      Purpose: The purpose of this paper was to study the bilateral choroidal thickness (CT) symmetry and differences in healthy individuals using wide-field swept-source optical coherence tomography (SS-OCT). Methods: All participants underwent a wide-field 16-mm 1-line scan using SS-OCT. CTs were measured at the following 12 points: 3 points at 900 µm, 1800 µm, and 2700 µm away from the nasal optic disc margin (nasal peripapillary area), 1 point at the subfovea, 6 points at 900 µm, 1800 µm, and 2700 µm away from the subfovea to the nasal and temporal areas (macular area), and 2 peripheral points at 2700 and ...

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    14. Follow-Up of Nonarteritic Anterior Ischemic Optic Neuropathy With Optical Coherence Tomography Angiography

      Follow-Up of Nonarteritic Anterior Ischemic Optic Neuropathy With Optical Coherence Tomography Angiography

      Purpose : The purpose of this study was to describe capillary changes in patients with nonarteritic anterior ischemic optic neuropathy (NAION) using optical coherence tomography-angiography (OCT-A) and correlate the results with best corrected visual acuity (BCVA), visual field, OCT retinal nerve fiber layer (RNFL), and combined thickness of ganglion cell and inner plexiform layers (GCIPL) thicknesses. Methods : We enrolled 22 eyes with acute NAION and 30 normal control (NC) subjects in this study. Whole en face image vessel density (WiVD) was measured in the radial peripapillary capillary plexus (RPC), superficial capillary plexus (SCP), and deep vascular complex (DVC) using OCT-A. The ...

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    15. Longitudinal Changes in Macular Optical Coherence Tomography Angiography Metrics in Primary Open-Angle Glaucoma With High Myopia: A Prospective Study

      Longitudinal Changes in Macular Optical Coherence Tomography Angiography Metrics in Primary Open-Angle Glaucoma With High Myopia: A Prospective Study

      Purpose : To characterize longitudinal changes in macular microvasculature as quantified from optical coherence tomography angiography (OCTA) metrics in primary open-angle glaucoma (POAG) eyes with and without high myopia. Methods : In total, 63 and 61 POAG eyes with and without high myopia, respectively, underwent swept-source OCTA imaging in at least four follow-up visits at an ophthalmic center, with a scanning protocol of 3- × 3-mm centered at the fovea. The foveal avascular zone (FAZ) area, FAZ circularity, and vessel density (VD) in both the superficial (SCP) and deep capillary plexuses (DCP) were measured. The rate of change in macular OCTA metrics over ...

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    16. The Macular Choriocapillaris Flow in Glaucoma and Within-Day Fluctuations: An Optical Coherence Tomography Angiography Study

      The Macular Choriocapillaris Flow in Glaucoma and Within-Day Fluctuations: An Optical Coherence Tomography Angiography Study

      Purpose: To assess quantitatively the choriocapillaris (CC) perfusion area in the macular area of healthy eyes, eyes with primary open-angle glaucoma, and eyes with ocular hypertension using optical coherence tomography angiography (OCTA). Methods: A consecutive series of healthy individuals and patients with glaucoma and ocular hypertension were recruited prospectively in this single-center, cross-sectional study based in Milan, Italy. OCTA was performed in the morning and evening, along with a complete ophthalmologic examination. Macular superficial capillary plexus vessel density (SCP-VD) and the thicknesses of the retina and ganglion cell complex (GCC), as well as their fluctuations, were investigated. Results: Thirty-nine eyes ...

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    17. Diabetic Macular Ischemia: Influence of Optical Coherence Tomography Angiography Parameters on Changes in Functional Outcomes Over One Year

      Diabetic Macular Ischemia: Influence of Optical Coherence Tomography Angiography Parameters on Changes in Functional Outcomes Over One Year

      Purpose : To prospectively evaluate whether diabetic macular ischemia detected with coherence tomography angiography (OCTA) is associated with change in functional outcomes over a period of one year. Methods : This is a one-year prospective, observational study that included 56 eyes with varying levels of diabetic retinopathy. All participants underwent best corrected visual acuity evaluation, swept-source OCTA and microperimetry at baseline and repeated at one year. Parafoveal vessel densities (VD) and foveal avascular zone (FAZ) areas were generated from OCTA in the superficial and deep vascular plexuses. The influence of baseline and change in OCTA parameters on change in visual acuity and ...

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    18. Assessment of Choroidal Vascularity and Choriocapillaris Blood Perfusion in Anisomyopic Adults by SS-OCT/OCTA

      Assessment of Choroidal Vascularity and Choriocapillaris Blood Perfusion in Anisomyopic Adults by SS-OCT/OCTA

      Purpose: To explore the association of choroidal vascularity and choriocapillaris blood perfusion with myopic severity in anisomyopes. Methods: Refractive error, axial length (AL), and other biometric parameters were measured in 34 anisomyopic young adults. Macular choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascularity index (CVI), were determined from swept-source optical coherence tomography (SS-OCT) vertical and horizontal B-scans. The percentage of choriocapillaris flow voids (FV%) was obtained from en face SS-OCT-angiography. Results: The spherical equivalent refraction (SER) was -3.35 ± 1.25 diopters in the more myopic eyes and ...

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    19. Focal Structure-Function Relationships in Primary Open-Angle Glaucoma Using OCT and OCT-A Measurements

      Focal Structure-Function Relationships in Primary Open-Angle Glaucoma Using OCT and OCT-A Measurements

      Purpose: To evaluate the focal structure-function associations among visual field (VF) loss, optical coherence tomography angiography (OCT-A) vascular measurements, and optical coherence tomography (OCT) structural measurements in glaucoma. Methods: In this cross-sectional study, subjects underwent standard automated perimetry, OCT-based nerve fiber thickness measurements, and OCT-A imaging. Mappings of focal VF test locations with OCT and OCT-A measurements were defined using anatomically adjusted nerve fiber trajectories and were studied using multivariate mixed-effects analysis. Segmented regression analysis was used to determine the presence of breakpoints in the structure-function associations. Results: The study included 119 eyes from 86 Chinese subjects with primary open-angle ...

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    20. Reduced Pulsatile Trabecular Meshwork Motion in Eyes With Primary Open Angle Glaucoma Using Phase-Sensitive Optical Coherence Tomography

      Reduced Pulsatile Trabecular Meshwork Motion in Eyes With Primary Open Angle Glaucoma Using Phase-Sensitive Optical Coherence Tomography

      Purpose: The purpose of this study was to investigate the difference in pulsatile trabecular meshwork (TM) motion between normal and eyes with POAG using phase-sensitive optical coherence tomography (PhS-OCT). Methods: In this cross-sectional study, eight healthy subjects (16 eyes) and nine patients with POAG (18 eyes) were enrolled. A laboratory-based prototype PhS-OCT system was used to measure pulsatile TM motion. PhS-OCT images were analyzed to obtain parameters of pulsatile TM motion (i.e. maximum velocity [MV] and cumulative displacement [CDisp]). Outflow facility and ocular pulse amplitude were measured using pneumotonography. Detection sensitivity was compared among various parameters by calculating the ...

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    21. Dynamic Optical Coherence Elastography of the Anterior Eye: Understanding the Biomechanics of the Limbus

      Dynamic Optical Coherence Elastography of the Anterior Eye: Understanding the Biomechanics of the Limbus

      Purpose : Currently, the biomechanical properties of the corneo-scleral limbus when the eye-globe deforms are largely unknown. The purpose of this study is to evaluate changes in elasticity of the cornea, sclera, and limbus when subjected to different intraocular pressures (IOP) using wave-based optical coherence elastography (OCE). Special attention was given to the elasticity changes of the limbal region with respect to the elasticity variations in the neighboring corneal and scleral regions. Methods : Continuous harmonic elastic waves (800 Hz) were mechanically induced in the sclera near the corneo-sclera limbus of in situ porcine eye-globes ( n = 8). Wave propagation was imaged using ...

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    22. Retinal Neurovascular Impairment in Patients with Essential Hypertension: An Optical Coherence Tomography Angiography Study

      Retinal Neurovascular Impairment in Patients with Essential Hypertension: An Optical Coherence Tomography Angiography Study

      Purpose : To investigate retinal neurovascular structural changes in patients with essential hypertension. Methods : This observational cross-sectional study consisted of 199 right eyes from 169 nondiabetic essential hypertensive patients, divided into groups as follows: group A, 113 patients with hypertensive retinopathy (HTNR); group B, 56 patients without HTNR; and a control group of 30 healthy subjects. Peripapillary retinal nerve fiber layer (RNFL), radial peripapillary segmented (RPC), ganglion cell–inner plexiform layer (GC-IPL), and superficial (SVP) and deep (DVP) vascular plexus density at the macula (6 × 6 mm 2 ) were measured by optical coherence tomography angiography (OCTA). Results : DVP density was significantly ...

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    23. Ultrahigh Resolution Spectral Domain Optical Coherence Tomography for the Assessment of Micro-Structural Changes in Central Serous Chorioretinopathy: A Pilot Study.

      Ultrahigh Resolution Spectral Domain Optical Coherence Tomography for the Assessment of Micro-Structural Changes in Central Serous Chorioretinopathy: A Pilot Study.

      Purpose : In central serous chorioretinopathy (CSCR), choroidal hyperpermeability associated with retinal pigment epithelium (RPE) impairment causes a leakage of fluid from the choroid into the subretinal space, with potential damage to the photoreceptors. We hypothesize that ultrahigh-resolution spectral domain optical coherence tomography (UHR SD-OCT) will enable more detailed assessment of structural changes in this condition. Methods : Patients in all stages of CSCR (acute, chronic and post-resolution) were imaged using an UHR SD-OCT prototype, with an 850 nm center wavelength and an axial resolution of ~2.7 µm in tissue at a 128kHz A-scan rate. Volumetric cube scans and high-density (HD ...

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    24. Evaluating the long-term effects of anti-vascular endothelial growth factor therapy on choroidal neovascularization in age-related macular degeneration using optical coherence tomography angiography

      Evaluating the long-term effects of anti-vascular endothelial growth factor therapy on choroidal neovascularization in age-related macular degeneration using optical coherence tomography angiography

      Purpose : Optical coherence tomography angiography (OCTA) allows for precise, non-invasive monitoring of changes to choroidal neovascularization (CNV) structure over time. The short-term effects of anti-vascular endothelial growth factor (anti-VEGF) treatment on CNV morphology is well described, but long-term studies on morphologic changes and correlation of such to the type of CNV have not been conducted. This study aims to determine if different types of CNVs in neovascular AMD (nAMD) behave differently with anti-VEGF treatment as visualized on OCTA. Methods : AMD Patients with treatment naive type 1, type 2, and type 3 CNVs were retrospectively screened for baseline and follow-up OCTA ...

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