1. All Articles

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    1. Choroidal Thickness Variation According to Refractive Error Measured by Spectral Domain-optical Coherence Tomography in Korean Children

      Choroidal Thickness Variation According to Refractive Error Measured by Spectral Domain-optical Coherence Tomography in Korean Children

      Purpose To assess choroidal thickness (CT) variation according to refractive errors using enhanced-depth imaging optical coherence tomography. Methods Eighty-nine eyes (in 89 children) <±6 diopter were categorized into three groups: hyperopia, emmetropia, and myopia, according to refractive error, and underwent choroidal scans using enhanced-depth imaging-optical coherence tomography. CT was measured at the fovea and at 1 mm and 3 mm nasal (N1 and N3), temporal (T1 and T3), superior (S1 and S3), and inferior (I1 and I3) from the fovea. Results Mean foveal CTs were 346.86 µm, 301.97 µm, and 267.46 µm in the hyperopia, emmetropia, and ...

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    2. Interchangeability and reliability of macular perfusion parameter measurements using optical coherence tomography angiography

      Interchangeability and reliability of macular perfusion parameter measurements using optical coherence tomography angiography

      Aim The aim of the study was to investigate the interchangeability and reliability of macular perfusion measurements using optical coherence tomography angiography. Methods A prospective cross-sectional observational study. Healthy adult Chinese subjects were recruited. Macular perfusion parameters were automatically analysed by software included in a spectral-domain optical coherence tomography system. The vessel density (VD) of the whole, parafovea, superior-hemi, inferior-hemi, fovea, temporal, superior, nasal and inferior quadrants as well as the foveal avascular zone (FAZ) and choroidal capillary VD (CCVD) were quantified. Results A total of 51 eyes in 27 subjects were included (8 men and 19 women, mean age ...

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    3. West Nile Virus Chorioretinitis With Foveal Involvement Evolution of Lesions on Optical Coherence Tomography

      West Nile Virus Chorioretinitis With Foveal Involvement Evolution of Lesions on Optical Coherence Tomography

      Purpose: To describe the clinical course of foveal West Nile virus (WNV) chorioretinitis with longitudinal spectral domain optical coherence tomography (SD-OCT) imaging. Methods: Case report. Results: A 41-year-old man with diabetes mellitus presented with flashes and floaters of both eyes (OU) and decreased vision of the right eye (OD) 2 weeks after being discharged from a local hospital. He had been treated for WNV meningoencephalitis, and he recovered systemically with supportive therapy. Ophthalmic examination revealed WNV chorioretinitis bilaterally, with predominantly foveal involvement OD. His best-corrected visual acuity (BCVA) was 8/200 OD and 20/20 of the left eye (OS ...

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    4. QUANTIFICATION OF RETINAL VESSEL TORTUOSITY IN DIABETIC RETINOPATHY USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

      QUANTIFICATION OF RETINAL VESSEL TORTUOSITY IN DIABETIC RETINOPATHY USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY

      Purpose: To investigate the association of vessel tortuosity with severity of diabetic retinopathy (DR) using optical coherence tomography angiography. Methods: We retrospectively analyzed 30 healthy eyes and 121 eyes of diabetic subjects with no DR, mild nonproliferative DR (NPDR), moderate to severe NPDR and proliferative DR (PDR). Binarized images were used to quantify the vessel tortuosity, vessel density, foveal avascular zone (FAZ) area, and FAZ acircularity. The vessels were divided vertically as superficial retinal layer and deep retinal layer, and horizontally as circular areas with 3 mm and 1.5 mm diameters. Analysis of variance was performed for multiple comparisons ...

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    5. SD-OCT Choroidal Thickness in Advanced Primary Open-Angle Glaucoma

      SD-OCT Choroidal Thickness in Advanced Primary Open-Angle Glaucoma

      Purpose: To assess the choroidal thickness in advanced primary open-angle glaucoma (POAG) comparing patients affected by advanced glaucoma and normal subject using spectral domain optical coherence tomography (SD-OCT). Methods: In total, 35 eyes of 35 patients affected by POAG with advanced perimetric defect (mean deviation worse than -12 dB) were prospectively enrolled and underwent a complete ophthalmologic examination, including enhanced depth imaging SD-OCT. One eye of 35 healthy subjects served as control group. Choroidal thickness was measured at the subfoveal location, at 0.5, 1.0, and 2.0 mm nasal and temporal to the fovea. Primary outcome measure was ...

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    6. Effects of diurnal, lighting, and angle-of-incidence variation on anterior segment optical coherence tomography (AS-OCT) angle metrics

      Effects of diurnal, lighting, and angle-of-incidence variation on anterior segment optical coherence tomography (AS-OCT) angle metrics

      Background First reported study to assess the effect of diurnal variation on anterior chamber angle measurements, as well as, to re-test the effects of lighting and angle-of-incidence variation on anterior chamber angle (ACA) measurements acquired by time-domain anterior segment optical coherence tomography (AS-OCT). Methods A total of 30 eyes from 15 healthy, normal subjects underwent anterior chamber imaging using a Visante time-domain AS-OCT according to an IRB-approved protocol. For each eye, the inferior angle was imaged twice in the morning (8 am – 10 am) and then again in the afternoon (3 pm – 5 pm), under light meter-controlled conditions with ambient ...

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    7. Influence of cataract on image quality and macular thickness measured using spectral domain optical coherence tomography: a prospective cohort study

      Influence of cataract on image quality and macular thickness measured using spectral domain optical coherence tomography: a prospective cohort study

      Background: Optical coherence tomography (OCT) is one of the most useful imaging techniques in the management of retinal diseases affecting the macula. Factors affecting the image quality of OCT may affect the macular thickness and hence treatment of retinal pathologies. This study was aimed to evaluate the influence of cataract on macular scans using spectral domain OCT. Methods: The prospective study was done in 36 patients with cataract. Cataract was graded as cortical, nuclear or posterior cataracts. All patients underwent small incision cataract surgery. Pre and post-operative imaging of the macula (4 weeks after surgery) using spectral domain OCT. The ...

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    8. Role of high resolution optical coherence tomography in diagnosing ocular surface squamous neoplasia with coexisting ocular surface diseases

      Role of high resolution optical coherence tomography in diagnosing ocular surface squamous neoplasia with coexisting ocular surface diseases

      Purpose Coexistence of an ocular surface disease can mask the typical features of ocular surface squamous neoplasia (OSSN). The purpose of this study was to evaluate high resolution optical coherence tomography (HR-OCT) as an adjunct in the detection and differentiation of OSSN within coexisting ocular surface pathologies. Methods Retrospective study of 16 patients with ocular surface disease and lesions suspicious for OSSN that were evaluated with HR-OCT. HR-OCT images of the lesions were taken to look for evidence of OSSN. Biopsies were performed in all cases, and the HR-OCT findings were compared to the histological results. Results Of the 16 ...

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    9. ADULT-ONSET FOVEOMACULAR VITELLIFORM DYSTROPHY EVALUATED BY MEANS OF OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY: A Comparison With Dry Age-Related Macular Degeneration and Healthy Eyes

      ADULT-ONSET FOVEOMACULAR VITELLIFORM DYSTROPHY EVALUATED BY MEANS OF OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY: A Comparison With Dry Age-Related Macular Degeneration and Healthy Eyes

      Purpose: To investigate alterations of superficial and deep retinal vascular densities, as well as of choroidal thickness, in patients affected by adult-onset foveomacular vitelliform dystrophy (AOFVD). Methods: A total of 22 eyes (15 patients) affected by AOFVD were recruited in the study. Furthermore, 20 eyes of 20 healthy subjects and 20 eyes of 18 patients affected by intermediate dry age-related macular degeneration (AMD) were enrolled. All patients underwent a complete ophthalmologic examination, including optical coherence tomography angiography. Outcome measures were superficial vessel density, deep vessel density, and choroidal thickness. Results: Parafoveal superficial vessel density was increased in patients with AOFVD ...

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    10. Relationship of Optic Nerve Structure and Function to Peripapillary Vessel Density Measurements of Optical Coherence Tomography Angiography in Glaucoma

      Relationship of Optic Nerve Structure and Function to Peripapillary Vessel Density Measurements of Optical Coherence Tomography Angiography in Glaucoma

      Purpose: To evaluate the sectoral and global structure-structure (vessel density-retinal nerve fiber layer thickness) and structure-function (vessel density-visual sensitivity loss) relationships of peripapillary vessel density measurements on optical coherence tomography angiography in primary open-angle glaucoma and to determine if fractional polynomial (FP) models characterize the relationships better than linear models. Materials and Methods: In a cross-sectional study, structure-structure and structure-function relationships of peripapillary vessel densities were determined in 227 eyes of 143 subjects (63 control and 164 primary open-angle glaucoma eyes) who had undergone standard automated perimetry and optical coherence tomography testing within 6 months of each other, using linear ...

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    11. MIT Receives a 2017 NIH Grant for $395,107 for Novel Diagnostics with Optical Coherence Tomography

      MIT Receives a 2017 NIH Grant for $395,107 for Novel Diagnostics with Optical Coherence Tomography

      MIT Receives a 2017 NIH Grant for $395,107 for Novel Diagnostics with Optical Coherence Tomography. The principal investigatyor is James Fujimoto. THe program began in 1985 adn ends in 2020/ Below is a summary of hte proposed workd This proposal is a resubmission of a competing renewal application for an ongoing collaborative program among investigators at the Massachusetts Institute of Technology, New England Eye Center and University of Pittsburgh Medical Center Eye Center. This is a multidisciplinary program which integrates imaging technology research, clinical and small animal imaging studies. The specific aims are: Aim 1. Next generation OCT technology ...

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    12. Iatrogenic Coronary Artery Dissection Induced During Invasive Absolute Coronary Blood Flow Measurement: Optical Coherence Tomography Findings

      Iatrogenic Coronary Artery Dissection Induced During Invasive Absolute Coronary Blood Flow Measurement: Optical Coherence Tomography Findings

      A 65-year-old woman with previous history of hypertension was referred to our institution due to effort angina with a positive exercise stress test. Coronary angiography showed normal coronary arteries. A vasospasm provocation test with methylergonovine was negative. With the aim of assessing the state of microvasculature, absolute coronary blood flow by thermodilution was performed as previously described.

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      Mentions: Fernando Alfonso
    13. OCT probes and OCT optical probe component for use therein

      OCT probes and OCT optical probe component for use therein

      An OCT optical probe component comprising: A rod having a first end and a second end, a lens situated proximate to the second end of the rod, the lens having a surface with an inner zone a, and an outer zone b, wherein the inner zone a is associated with the focal length fla, and said outer zone b is associated with the focal length flb, such that optical probe component is multi-focal, the optical probe capable of imaging at multiple image planes, via the lens of an object adjacent to the first end of the rod, wherein the at ...

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      Mentions: Corning
    14. Focus defect and dispersion mismatch in full-field optical coherence microscopy

      Focus defect and dispersion mismatch in full-field optical coherence microscopy

      Full-field optical coherence microscopy (FFOCM) is an optical technique, based on low-coherence interference microscopy, for tomographic imaging of semi-transparent samples with micrometer-scale spatial resolution. The differences in refractive index between the sample and the immersion medium of the microscope objectives may degrade the FFOCM image quality because of focus defect and optical dispersion mismatch. These phenomena and their consequences are discussed in this theoretical paper. Experimental methods that have been implemented in FFOCM to minimize the adverse effects of these phenomena are summarized and compared.

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    15. Imaging outcomes of bioresorbable scaffold overlap: an optical coherence tomography analysis from the ABSORB EXTEND trial

      Imaging outcomes of bioresorbable scaffold overlap: an optical coherence tomography analysis from the ABSORB EXTEND trial

      Aims: The purpose of this study was to assess the vascular response and vessel healing of overlapped Absorb scaffolds (Abbott Vascular, Santa Clara, CA, USA) compared to non-overlapped devices in human coronary arteries as assessed by optical coherence tomography (OCT) in the same treated segment. Methods and results: The ABSORB EXTEND (NCT01023789) trial is a prospective, single-arm, openlabel clinical study which enrolled 800 patients. The planned overlap OCT subgroup in the ABSORB EXTEND trial was analysed and two-year OCT follow-up was performed in seven patients. In cross-section level analysis at baseline, lumen and abluminal scaffold areas were larger in overlap ...

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    16. Combined spectral-domain optical coherence tomography and hyperspectral imaging applied for tissue analysis: preliminary results

      Combined spectral-domain optical coherence tomography and hyperspectral imaging applied for tissue analysis: preliminary results

      In recent years many optoelectronic techniques have been developed for improvement and the development of devices for tissue analysis. Spectral-Domain Optical Coherence Tomography (SD-OCT) is a new medical interferometric imaging modality that provides depth resolved tissue structure information with resolution in the μm range. However, SD-OCT has its own limitations and cannot offer the biochemical information of the tissue. These data can be obtained with hyperspectral imaging, a non-invasive, sensitive and real time technique. In the present study we have combined Spectral-Domain Optical Coherence Tomography (SD-OCT) with Hyperspectral imaging (HSI) for tissue analysis. The Spectral-Domain Optical Coherence Tomography (SD-OCT) and ...

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    17. A Case Report of Occipital Lobe Epilepsy and Related Optical Coherence Tomography Findings

      A Case Report of Occipital Lobe Epilepsy and Related Optical Coherence Tomography Findings

      Purpose In the present case report, visual pathway damage confirmed by retinal ganglion cell layer (GCL) damage on optical coherence tomography (OCT) in occipital lobe epilepsy was described. Case summary A 25-year-old female with idiopathic generalized epilepsy developed visual blurring followed by a generalized seizure. On brain magnetic resonance imaging (MRI), very subtle changes of the cortex in the left parietooccipital lobe were observed. Two days after the attack, even after the disappearance of epileptiform wave on electroencephalogram (EEG), visual acuity in both eyes was 0.5 and a perimetry revealed nearly complete visual defect in both eyes. OCT showed ...

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    18. Comparison of Central Corneal Thickness Measured by Swept-source Optical Coherence Tomography and Ultrasound Pachymetry

      Comparison of Central Corneal Thickness Measured by Swept-source Optical Coherence Tomography and Ultrasound Pachymetry

      Purpose To analyze and compare ultrasound pachymetry (USP) with a more recently adopted device, the intra ocular lens (IOL) master 700, which are both used to measure central corneal thickness. Methods The central corneal thickness was measured in 24 eyes of 12 glaucoma patients and in 83 eyes of 42 normal patients. First, the IOL master 700 was used to measure the central corneal thickness, followed by measurements taken using USP later. The results were analyzed using a paired t -test. We analyzed the agreement and the correlations between the two test devices by using Bland-Altman plots and the Pearson ...

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    19. One-year follow-up optical coherence tomography after endovascular treatment with a new-generation zotarolimus-eluting stent for chronic mesenteric ischemia

      One-year follow-up optical coherence tomography after endovascular treatment with a new-generation zotarolimus-eluting stent for chronic mesenteric ischemia

      A 62-year-old man experienced lower abdominal pain triggered by a hypotensive episode during hemodialysis for end-stage renal failure. Computed tomography scan and subsequent angiography revealed a significant calcified stenosis at the proximal part of inferior mesenteric artery (IMA) ( Fig. 1 A-C). Abdominal angina was diagnosed and his symptoms were reproduced during intentional hypotension induced by intravenous administration of calcium channel blocker with drop in the Pd/Pa within the IMA lesion from 0.90 to 0.80. In addition, the balloon occlusion during endovascular treatment as described below also reproduced his symptoms. Pre-procedural optical coherence tomography (OCT) showed a lipid-rich ...

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      Mentions: Yusuke Fujino
    20. Speckle noise reduction for optical coherence tomography images via non-local weighted group low-rank representation

      Speckle noise reduction for optical coherence tomography images via non-local weighted group low-rank representation

      In this work, a non-local weighted group low-rank representation (WGLRR) model is proposed for speckle noise reduction in optical coherence tomography (OCT) images. It is based on the observation that the similarity between patches within the noise-free OCT image leads to a high correlation between them, which means that the data matrix grouped by these similar patches is low-rank. Thus, the low-rank representation (LRR) is used to recover the noise-free group data matrix. In order to maintain the fidelity of the recovered image, the corrupted probability of each pixel is integrated into the LRR model as a weight to regularize ...

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    21. Near-IR and CP-OCT imaging of suspected occlusal caries lesions

      Near-IR and CP-OCT imaging of suspected occlusal caries lesions

      Introduction Radiographic methods have poor sensitivity for occlusal lesions and by the time the lesions are radiolucent they have typically progressed deep into the dentin. New more sensitive imaging methods are needed to detect occlusal lesions. In this study, cross-polarization optical coherence tomography (CP-OCT) and near-IR imaging were used to image questionable occlusal lesions (QOC's) that were not visible on radiographs but had been scheduled for restoration on 30 test subjects. Methods Near-IR reflectance and transillumination probes incorporating a high definition InGaAs camera and near-IR broadband light sources were used to acquire images of the lesions before restoration. The ...

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    22. Feature of The Week 03/26.2017: Segmentation of nucleus and cytoplasm of a single cell in 3D tomogram using OCT

      Feature of The Week 03/26.2017: Segmentation of nucleus and cytoplasm of a single cell in 3D tomogram using OCT

      uclear-to-cytoplasmic (N/C) ratio is an effective feature to distinguish cancer cells from their normal counterparts. In conventional cytopathology, cells printed or smeared on a glass slide were stained and then evaluated by two-dimensional (2D) images through light microscopy. A random rayburst sampling (RRBS) framework was developed to detect the nucleus and cell membrane boundaries in three-dimensional (3D) space. Raw images were acquired through a full-field optical coherence tomography (FF-OCT) system with submicron resolution—i.e. 0.8 µm in lateral and 0.9 µm in axial direction. The near isometric resolution enables 3D segmentation of nucleus and cell membrane ...

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