1. Articles from iovs.org

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    1. Preservation of the Photoreceptor Layer following Subthreshold Laser Treatment for Diabetic Macular Edema as Demonstrated by SD-OCT

      Preservation of the Photoreceptor Layer following Subthreshold Laser Treatment for Diabetic Macular Edema as Demonstrated by SD-OCT

      Purpose: Subthreshold laser treatment of diabetic macular edema (DME) may have less deleterious effects on the photoreceptors than regular continuous wave laser. This study aimed to assess whether subthreshold laser causes a long-term damage to the retinal structures, as demonstrated by spectral-domain optical coherence tomography (SD-OCT), and to evaluate the change in the axial diameter of retinal diabetic microaneurysms following treatment. Methods: A retrospective study of eyes that were diagnosed with non-foveal involving DME and underwent subthreshold laser treatment with the Lumenis Novus SRT system. SD-OCT scans of treated retinal areas, performed prior to treatment and approximately 4 months following ...

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    2. Potential new diagnostic tool for Alzheimer's disease using a linear discriminant function for Fourier domain optical coherence tomography

      Potential new diagnostic tool for Alzheimer's disease using a linear discriminant function for Fourier domain optical coherence tomography

      Purpose: To calculate and validate a linear discriminant function (LDF) for Fourier domain optical coherence tomography (OCT) to improve the diagnostic ability of retinal and retinal nerve fiber layer (RNFL) thickness parameters in the detection of Alzheimer's disease (AD). Method: AD patients (n=151) and age-matched, healthy subjects (n=61) were enrolled. The Cirrus and Spectralis OCT systems were used to obtain retinal measurements and circumpapillary RNFL thickness for each participant. A LDF was calculated using all retinal and RNFL OCT measurements. Receiver operating characteristic (ROC) curves were plotted and compared among the LDF and the standard parameters provided ...

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    3. Advancing OCT Algorithmic Standardization

      Advancing OCT Algorithmic Standardization

      Neovascular exudative AMD (wet AMD) continues to rank as a top reason to visit eye care specialists, and the early identification of this disease has important prognostic implications for patients. 1 Advancements in optical coherence tomography (OCT) imaging have surpassed other modalities in the ability to detect the earliest development of wet AMD and prompt treatment initiation, in spite of lack of inter- and intradevice standardization. 2 , 3 Zhang et al. 4 present a novel, automated way to detect changes at the border where choroidal neovascularization (CNV) first affects the retina. They use a technique that presents an automated method ...

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    4. Structure-Function Correlations in Glaucoma Using Matrix and Standard Automated Perimetry Versus Time Domain and Spectral Domain OCT devices

      Structure-Function Correlations in Glaucoma Using Matrix and Standard Automated Perimetry Versus Time Domain and Spectral Domain OCT devices

      Purpose: To examine the structure-function relationship between two perimetric tests, the Frequency-Doubling Technology (FDT) Matrix and Standard Automated Perimetry (SAP), and two Optical Coherence Tomography (OCT) devices (Time-Domain and Spectral-Domain). Methods: This cross-sectional study included 97 eyes from 29 healthy individuals and 68 individuals with early, moderate, or advanced primary open-angle glaucoma. The correlations between overall and sectorial parameters of retinal nerve fiber layer thickness (RNFL) measured with Stratus and Spectralis OCT and the visual field sensitivity obtained with FDT Matrix and SAP were assessed. The relationship was also evaluated using a previously described linear model. Results: The correlation coefficients ...

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    5. Correlation between Spectral-Domain OCT findings and Visual Acuity in X-linked Retinoschisis

      Correlation between Spectral-Domain OCT findings and Visual Acuity in X-linked Retinoschisis

      PURPOSE: To investigate the tomographic characteristics of the outer retina and choroid and their relationship with visual auity in X-linked juvenile retinoschisis (XLRS) patients using spectral-domain optical coherence tomography (SD-OCT). METHODS: In this retrospective, observational, case-control study, we analyzed 20 eyes of 10 patients with XLRS using SD-OCT. The clinical and tomographic features of the outer retina, including the external limiting membrane (ELM), inner segment/outer segment (IS/OS) junction, cone cell outer segment tips (COST) line, photoreceptor outer segment (PROS) length, and choroid, were evaluated. As controls, 40 age-, sex-, and refraction-matched healthy eyes (1:2 matched) were randomly ...

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    6. Structure-function relationships with spectral-domain optical coherence tomography retinal nerve fiber layer and optic nerve head measurements

      Structure-function relationships with spectral-domain optical coherence tomography retinal nerve fiber layer and optic nerve head measurements

      Purpose: To evaluate the regional structure-function relationship between visual field sensitivity and retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) measurements using spectral-domain optical coherence tomography (SD-OCT). Methods: Prospective cross-sectional study conducted on patients with glaucoma, suspected glaucoma and healthy subjects. Eyes were tested on Cirrus OCT and standard achromatic perimetry. RNFL thickness of 12 peripapillary 30° sectors, neuroretinal rim thickness extracted from 36 neuroretinal rim scans, and Bruch membrane opening minimum rim width (BMO-MRW) - a recently defined parameter - extracted from 36 neuroretinal rim scans were obtained. Correlations between peripapillary RNFL thickness, neuroretinal rim thickness, all six ...

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    7. Choroidal thickness in patients with reticular pseudodrusen using 3D-1060nm OCT maps

      Choroidal thickness in patients with reticular pseudodrusen using 3D-1060nm OCT maps

      Purpose: To map and analyze choroidal thickness (ChT) in age-related macular degeneration patients with reticular pseudodrusen (RPD) using 3-dimensional (3D) 1060nm optical coherence tomography (OCT). Methods: Fifty eyes from twenty-five patients with RPD were grouped according to the severity of age-related macular degeneration (AMD) and the presence of RPD. All patients were imaged by high speed (60.000 A-scans/s) 3D-1060nm OCT over a 36x36° field of view. ChT-maps were automatically generated and compared to RPD areas visualized by fundus autofluorescence and infra-red imaging. Retinal thickness maps, ChT maps, Haller's and Sattler's layer thickness were statistically analyzed between ...

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    8. Posterior Precortical Vitreous Pockets and Connecting Channels in Children on Swept-Source Optical Coherence Tomography

      Posterior Precortical Vitreous Pockets and Connecting Channels in Children on Swept-Source Optical Coherence Tomography

      PURPOSE. To observe the posterior vitreous in children using swept-source optical coherence tomography (SS-OCT). METHODS. The normal right eyes of 73 children (ages, 3-11) years were studied using SS-OCT with 12-mm horizontal and vertical scans in the posterior fundus. RESULTS. Posterior precortical vitreous pockets (PPVPs), narrow liquefied spaces along the vitreoretinal interface in the macula (mean, 165.4±35.2 µm (depth) x 3,327±615.7 µm (width), were observed at age 3 in horizontal scans. The PPVPs enlarged to 382.9±51.8 x 4,486.5±342.3 from ages 4 to 6 (P<0.01) and ...

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      Mentions: Gunma University
    9. Pilocarpine-induced dilation of Schlemm's canal and prevention of lumen collapse at elevated intraocular pressures in living mice visualized by OCT

      Pilocarpine-induced dilation of Schlemm's canal and prevention of lumen collapse at elevated intraocular pressures in living mice visualized by OCT

      Purpose:The goal was to assess effects of intraocular pressure (IOP) and pilocarpine-induced ciliary muscle contraction on conventional outflow pathway tissues in living anesthetized mice. Methods:IOP was controlled by intracameral cannulation of mouse eyes while imaging using spectral domain optical coherence tomography (SD-OCT). Time-lapse sagittal SD-OCT sections through Schlemm's canal (SC) were acquired while changing IOP stepwise between 10 and 45 mmHg. After topical application of 1% pilocarpine, the series of IOP steps and imaging were repeated. Effects of pilocarpine on IOP and outflow facility in living mice were verified by rebound tonometry and flow measurements at 3 ...

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    10. Three-dimensional Optical Coherence Tomography Evaluation of Vascular Changes at Arteriovenous Crossings

      Three-dimensional Optical Coherence Tomography Evaluation of Vascular Changes at Arteriovenous Crossings

      Purpose:To study the three-dimensional morphological features of retinal arteriovenous crossings with optical coherence tomography (OCT) and elucidate the vascular changes associated with crossing phenomena as seen on fundus photographs. Methods: We examined 150 consecutive eyes with no ocular disease. In each eye, fundus photographs were taken, and one randomly selected arteriovenous crossing was examined by OCT. The OCT analysis was performed using sequential thin sections along and perpendicular to the retinal vessels. Results:OCT analysis of these arteriovenous crossings showed that the veins abruptly changed their directions to pass the artery and frequently displayed focal luminal narrowing with no ...

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    11. Quantifying disrupted outer retina-subretinal layer in SD-OCT images in choroidal neovascularization

      Quantifying disrupted outer retina-subretinal layer in SD-OCT images in choroidal neovascularization

      Purpose: To report a fully automated method to identify and quantify the thickness of the outer retinal-subretinal (ORSR) layer from clinical spectral-domain optical coherence tomography (SD-OCT) scans of choroidal neovascularization (CNV) due to exudative age-related macular degeneration (e-AMD). Methods: 23 Subjects with CNV met eligibility. Volumetric SD-OCT scans of 23 eyes were obtained (Zeiss Cirrus, 200×200×1024 voxels). In a subset of eyes, scans were repeated. OCT volumes were analyzed using our standard parameters and using a 3D graph-search approach with an adaptive cost function. A retinal specialist graded the segmentation as generally accurate, local segmentation inaccuracies, or failure ...

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    12. Comparison of Dynamic Changes in Anterior Ocular Structures Examined with Anterior Segment Optical Coherence Tomography in a Cohort of Various Origins

      Comparison of Dynamic Changes in Anterior Ocular Structures Examined with Anterior Segment Optical Coherence Tomography in a Cohort of Various Origins

      Purpose: To identify risk factors for angle closure from iris and angle anterior segment optical coherence tomography (ASOCT) measurements and to determine if these differ by geographic origin. Methods: ASOCT images from 267 clinic-based persons were compared between bright and dark conditions. An automated program quantified angle and iris parameters. Results: Iris area in bright light was larger with increasing age (univariate regression, p=0.0005), and largest in European and African-derived and smallest in Korean and Chinese eyes (multivariable regression, p=0.0001). Iris area was significantly larger in AC groups compared to normal and open angle glaucoma groups ...

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    13. Comparison of Time- and Spectral-Domain Optical Coherence Tomography in Management of Diabetic Macular Edema

      Comparison of Time- and Spectral-Domain Optical Coherence Tomography in Management of Diabetic Macular Edema

      Purpose: Some clinical trials that proved the benefits of anti-VEGF therapy for diabetic macular edema (DME) based retreatment decisions on visual acuity and time-domain ocular coherence tomography (TD-OCT) central subfield thickness changes since the last treatment. This study assessed the impact of TD-OCT followed by spectral domain (SD)-OCT on as needed treatment decision-making in the management of DME with anti-VEGF medications. Methods: Patients previously treated for DME with anti-VEGF medications in the Retina Division of the Wilmer Eye Institute, following an IRB approved informed consent process, underwent clinical examination, TD- and SD-OCT imaging. Their retina specialists recorded whether additional ...

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    14. Quantitative Fundus Autofluorescence and Optical Coherence Tomography in Best Vitelliform Macular Dystrophy

      Quantitative Fundus Autofluorescence and Optical Coherence Tomography in Best Vitelliform Macular Dystrophy

      Purpose: Quantitative fundus autofluorescence (qAF), spectral domain optical coherence tomography (SD-OCT) segmentation and multimodal imaging were performed to elucidate the pathogenesis of Best vitelliform macular dystrophy (BVMD) and to identify abnormalities in lesion versus non-lesion fundus areas. Methods: 16 patients with a clinical diagnosis of BVMD were studied. AF images (30°, 488 nm excitation) were acquired with a confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference to account for variable laser power and detector sensitivity. The grey levels (GLs) of each image were calibrated to the reference, zero GL, magnification, and normative optical media density, to yield qAF ...

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    15. Assessing sodium iodate induced outer retinal changes in rats using confocal scanning laser ophthalmoscopy and optical coherence tomography

      Assessing sodium iodate induced outer retinal changes in rats using confocal scanning laser ophthalmoscopy and optical coherence tomography

      Purpose: Sodium iodate induces retinal pigment epithelium (RPE) atrophy and photoreceptor degeneration, as seen in the pathogenesis of many retinal diseases. We investigated a new approach of analyzing retinal images using confocal scanning laser ophthalmoscopy (cSLO), which allows longitudinal assessment of sodium iodate induced lesions in the retina of living rats. Methods: Single dose of sodium iodate (25 to 75 mg/kg) was given intravenously to adult Sprague-Dawley rats. Control animals were given normal saline or sodium iodide. The retina was examined by cSLO and optical coherence tomography (OCT) in living rats, which were then sacrificed for histological assessments. Results ...

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    16. Detection and Analysis of Hard Exudates by Polarization-Sensitive Optical Coherence Tomography in Patients with Diabetic Maculopathy

      Detection and Analysis of Hard Exudates by Polarization-Sensitive Optical Coherence Tomography in Patients with Diabetic Maculopathy

      Purpose: To image and analyze hard exudates (HE) and their precursors in patients with diabetic macular edema (DME) using polarization sensitive optical coherence tomography (PS-OCT). Methods: Twenty-two eyes of 16 patients with DME were imaged using color fundus photography (CF) and PS-OCT. In PS-OCT, HE were automatically detected based on their distinct polarization-scrambling qualities. CF images were manually graded for the presence of HE by two masked graders and correlated with the corresponding PS-OCT HE maps: corresponding images were overlaid and an identical grid of 128x128 fields was used for correlation of detected HE. Results: In all eyes, HE were ...

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    17. Vitreous Changes in High Myopia Observed by Swept-Source Optical Coherence Tomography

      Vitreous Changes in High Myopia Observed by Swept-Source Optical Coherence Tomography

      PURPOSE. To observe vitreous changes in high myopia using swept-source optical coherence tomography (SS-OCT). METHODS. We performed slit-lamp biomicroscopy and SS-OCT in the highly myopic right eyes of 151 patients (mean age, 52.7 years; mean refraction, -11.4 diopters [D]) and the right eyes with no myopia of 363 healthy control volunteers (mean age, 52.8 years; mean refraction, -1.4 D). To estimate the sizes of the posterior precortical vitreous pockets (PPVPs), we measured the height between the fovea and the anterior border of the PPVPs. RESULTS. Patients with partial posterior vitreous detachments (PVDs) around the macula and ...

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      Mentions: Gunma University
    18. Tear meniscus volume changes in dacryocystorhinostomy evaluated with quantitative measurement using anterior segment optical coherence tomography

      Tear meniscus volume changes in dacryocystorhinostomy evaluated with quantitative measurement using anterior segment optical coherence tomography

      PURPOSE: To evaluate tear meniscus (TM) changes in external dacryocystorhinostomy (ex-DCR) with quantitative measurement on tear meniscus height (TMH), area (TMA) and volume (TMV) using an anterior segment optical coherence tomography (AS-OCT). METHODS: Twenty-one patients of 25 eyes (11 males and 10 females) with a primary acquired nasolacrimal duct obstruction (PANDO) who received ex-DCR from May 2010 to April 2011 were evaluated prospectively on their TMH, TMA, and TMV changes by AS-OCT. Measurements were performed before surgery (Pre), and 2 weeks (2W), 2 months (2M), and 6 months (6M) after surgery. Data was analyzed using Kruskal-Wallis test, Wilcoxon signed-rank test ...

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    19. Automated Segmentation of Optic Nerve Head Structures with Optical Coherence Tomography

      Automated Segmentation of Optic Nerve Head Structures with Optical Coherence Tomography

      Purpose: To quantify and characterise the difference between automated and manual segmentation of optic nerve head structures with spectral domain-optical coherence tomography (SD-OCT). Methods: Optic nerve head radial scans in 107 glaucoma patients and 48 healthy controls were conducted with SD-OCT. Independent segmentations of the internal limiting membrane (ILM) and Bruch's membrane opening (BMO) were performed manually with custom software and with an automated algorithm in each radial scan. The minimum distance between BMO and ILM, termed BMO-minimum rim width (BMO-MRW) was calculated with each segmentation method. Absolute differences between automated and manual segmentations of ILM (ΔILM) and BMO ...

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    20. OCT evaluation of neuroprotective effects of tafluprost on retinal injury after intravitreal injection of endothelin-1 in the rat eye

      OCT evaluation of neuroprotective effects of tafluprost on retinal injury after intravitreal injection of endothelin-1 in the rat eye

      Purpose: To determine whether optical coherence tomography (OCT) is a useful technique to monitor retinal damage and to evaluate the neuroprotective effect of topical tafluprost in a rat model of intravitreal endothelin-1 (ET-1) injection. Methods: A single intravitreal injection of ET-1 (0.2-200 pmol/eye) was performed in one eye. OCT imaging was performed until 2 weeks after ET-1 injection. Subsequently, an intravitreal injection of ET-1 (20 pmol/eye) was performed in one eye of each rat, which was followed by topical instillation of tafluprost or saline once daily for 4 weeks. OCT imaging was performed until 4 weeks after ...

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    21. Noninvasive Imaging of Retinal Morphology and Microvasculature in Obese Mice using Optical Coherence Tomography and Optical Microangiography

      Noninvasive Imaging of Retinal Morphology and Microvasculature in Obese Mice using Optical Coherence Tomography and Optical Microangiography

      Purpose:To evaluate early diabetes-induced changes in retinal thickness and microvasculature in a type II diabetic mouse model using OCT/OMAG. Methods:22 week old obese BTBR mice (OB, n=10) and wild type control mice (WT, n=10) were imaged. Three-dimensional data were captured with OCT using an ultrahigh sensitive OMAG scanning protocol for 3D angiography of the retina and dense A-scan protocol for measurement of the total retinal blood flow (RBF) rate. The thickness of the nerve fiber layer (NFL) and NFL to inner plexiform layer (IPL) were measured and compared between OB and WT mice. The linear ...

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    22. Electrophysiology and optical coherence tomography to evaluate Parkinson disease severity

      Electrophysiology and optical coherence tomography to evaluate Parkinson disease severity

      Objective: To evaluate correlations between visual evoked potentials (VEP), pattern electroretinogram (PERG), and macular and retinal nerve fiber layer (RNFL) thickness measured by optical coherence tomography (OCT) and the severity of Parkinson disease (PD). Methods: Forty-six PD patients and 33 age and sex-matched healthy controls were enrolled, and underwent VEP, PERG, and Cirrus and Spectralis OCT measurements of macular and RNFL thicknesses, and evaluation of PD severity using the Hoehn & Yahr scale to measure PD symptom progression, the Schwab and England Activities of Daily Living Scale (SE-ADL) to evaluate patient quality of life (QOL), and disease duration. Logistical regression was ...

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    23. Differential Vulnerability of Retinal Layers to Early Age-Related Macular Degeneration: Evidence by SD-OCT Segmentation Analysis.

      Differential Vulnerability of Retinal Layers to Early Age-Related Macular Degeneration: Evidence by SD-OCT Segmentation Analysis.

      Purpose:To evaluate layer-by-layer retinal thickness in spectral-domain optical coherence tomography (SD-OCT), determined by automated segmentation analysis (ASA) software in healthy and early age-related maculopathy (ARM) eyes. Methods:Fifty-seven eyes, specifically, 19 healthy eyes under 60 years old, 19 healthy eyes over 60, and 19 ARM eyes, were recruited into this cross-sectional study. The mean ages were 36.78 (SD: ± 13.82), 69.89 (SD: ± 6.14) and 66.10 (SD: ± 8.67) years, respectively, in the three study groups. SD-OCT scans were transferred into a dedicated software program that performed automated segmentation of different retinal layers. Results:Automated layer ...

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    24. Improving Glaucoma Detection Using Spatially Correspondent Clusters of Damage and by Combining Standard Automated Perimetry and Optical Coherence Tomography

      Improving Glaucoma Detection Using Spatially Correspondent Clusters of Damage and by Combining Standard Automated Perimetry and Optical Coherence Tomography

      PURPOSE. To improve the detection of glaucoma, techniques for assessing local patterns of damage and for combining structure and function were developed. METHODS. Standard automated perimetry (SAP) and frequency-domain optical coherence tomography (fdOCT) data, consisting of macular retinal ganglion cell plus inner plexiform layer (mRGCPL) as well as macular and optic disc retinal nerve fiber layer (mRNFL and dRNFL) thicknesses, were collected from 52 eyes of 52 healthy controls and 156 eyes of 96 glaucoma suspects and patients. In addition to generating simple global metrics, SAP and fdOCT data were searched for contiguous clusters of abnormal points and converted to ...

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    1-24 of 532 1 2 3 4 ... 21 22 23 »
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