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    1. Optical coherence tomography angiography findings in axial spondylarthritis

      Optical coherence tomography angiography findings in axial spondylarthritis

      The aim of this study is to evaluate the density of retinal vascular structures and their relationship with disease duration and activity in patients with axial spondylarthritis (axSpA) using optical coherence tomography angiography (OCT-A). In this case–control study, 56 eyes of 29 axSpA patients and 61 eyes of 31 healthy controls (HCs) were evaluated using OCT-A. The capillary plexus density (CPD) of vessels in the parafovea and perifovea regions was evaluated from the superficial capillary plexus (SCP) and deep capillary plexus (DPC) flow areas. The CPD of vessels in the fundus was evaluated from the radial peripapillary capillary (RPC ...

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    2. Reproducibility and agreement of four anterior segment-optical coherence tomography devices for anterior chamber angle measurementsv

      Reproducibility and agreement of four anterior segment-optical coherence tomography devices for anterior chamber angle measurementsv

      Purpose To compare the reproducibility and agreement of anterior chamber angle (ACA) parameters and metrics obtained by four different anterior segment-optical coherence tomography (AS-OCT) devices. Methods In this prospective study, 30 eyes from 15 normal subjects underwent anterior segment angle scanning using the Spectralis, Cirrus, and Optovue spectral domain optical coherence tomography (SD-OCT), as well as the Visante time-domain optical coherence tomography (TD-OCT). For each eye, the scan line was performed perpendicularly on the inferior (270°) angle, and the inferior ACA image was acquired 2 times. Inter-instrument and intra-instrument, as well as inter-observer and intra-observer reproducibility of anterior chamber angle ...

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    3. Plasma Ceramides in Relation to Coronary Plaque Characterization Determined by Optical Coherence Tomography

      Plasma Ceramides in Relation to Coronary Plaque Characterization Determined by Optical Coherence Tomography

      Plasma ceramides (Cer), a subset of bioactive lipids, have mechanistic links to development of atherosclerosis and are related to major adverse cardiovascular events (MACEs). Previous researches have demonstrated vulnerable plaques contribute to acute cardiovascular events and poor prognosis. This study aimed to explore the associations between Cer and culprit plaque characterizations evaluated by optical coherence tomography (OCT). It was found that plasma Cer are associated with culprit plaque vulnerability evaluated by OCT, providing evidence supporting proatherogenic roles and potential to act as markers for plaque vulnerability of Cer.

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    4. Features of cotton wool spots in diabetic retinopathy: a spectral-domain optical coherence tomography angiography study

      Features of cotton wool spots in diabetic retinopathy: a spectral-domain optical coherence tomography angiography study

      Purpose To describe the features of cotton wool spots (CWSs) in diabetic retinopathy (DR) by using spectral-domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCT angiography). Methods We retrospectively studied patients with DR who presented CWSs and had been imaged by SD-OCT angiography. The retinal layer localisation and dimensions of the CWSs were assessed on SD-OCT, while the decorrelation signal generated by the CWSs and the vascular density (VD) of the superficial capillary plexus (SCP) and deep capillary plexus around the CWSs and in the macula were assessed on OCT angiography. Results A total of 87 eyes of ...

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    5. Application of Phase Correction for Compensation of Motion Artifacts in Spectral-Domain Optical Coherence Tomography

      Application of Phase Correction for Compensation of Motion Artifacts in Spectral-Domain Optical Coherence Tomography

      The application of computational methods to correct distortions in spectral-domain optical coherence tomography due to fast probe movements relative to a studied object is described. This technique is intended for use in endoscopy or in the study of external biological tissues using a handheld probe. The effectiveness of the method was confirmed experimentally.

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    6. Assessment of superficial and deep retinal vessel density in systemic lupus erythematosus patients using optical coherence tomography angiography

      Assessment of superficial and deep retinal vessel density in systemic lupus erythematosus patients using optical coherence tomography angiography

      Purpose The aim of this study is to evaluate the retinal microvascular density in SLE patients using optical coherence tomography angiography (OCTA) and to correlate vascular density with the disease activity and damage risk. Methods Twenty eyes of 20 SLE patients were compared with 20 eyes of normal subjects. The retinal capillary plexuses were examined by OCTA. The disease activity and damage risk were evaluated by the SLEDAI-2 K and SLICC/ACR SDI scoring systems. Results No difference was found between SLE patients’ central foveal thickness (CFT) and foveal avascular zone (FAZ) area and the normal ( P  > 0.05). SLE ...

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    7. Features of neovascularization in pachychoroid neovasculopathy compared with type 1 neovascular age-related macular degeneration on optical coherence tomography angiography

      Features of neovascularization in pachychoroid neovasculopathy compared with type 1 neovascular age-related macular degeneration on optical coherence tomography angiography

      Purpose To compare neovascular membrane features of pachychoroid neovasculopathy (PNV) and type 1 neovascular age-related macular degeneration (nAMD) using optical coherence tomography angiography (OCTA). Design Retrospective study. Methods We assessed 34 treatment-naïve eyes with a diagnosis of PNV and 36 treatment-naïve eyes with a diagnosis of type 1 nAMD. Morphological patterns of neovascular membranes were categorized, and lesion sizes and flow areas were calculated by using en face images on the AngioVue (Optovue) OCTA system. Results Statistically significant differences were found between groups in age ( P =0.001), baseline best corrected visual acuity ( P =0.005), and baseline ...

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    8. Spectral domain optical coherence tomography classification of diabetic macular edema: a new proposal to clinical practice

      Spectral domain optical coherence tomography classification of diabetic macular edema: a new proposal to clinical practice

      Purpose To classify the types of diabetic macular edema (DME) and evaluate its morphological features on spectral domain optical coherence tomography (SD-OCT) and determine correlations between visual acuity and OCT findings. Methods We assessed 406 eyes of 309 patients with a diagnosis of DME retrospectively. Three types based on SD-OCT were identified: diffuse macular edema, cystoid macular edema, and cystoid degeneration. Morphological features such as serous macular detachment (SMD), vitreomacular interface abnormalities (VMAI), hard exudates, photoreceptor status, and correlations between visual acuity and those morphological features were also evaluated by SD-OCT. Results The most common type of DME was cystoid ...

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    9. Quantitative assessment of the retinal microvasculature and choriocapillaris in myopic patients using swept-source optical coherence tomography angiography

      Quantitative assessment of the retinal microvasculature and choriocapillaris in myopic patients using swept-source optical coherence tomography angiography

      Purpose To study the retinal capillary microvasculature and the choriocapillaris (CC) in myopic eyes using swept-source optical coherence tomography angiography (SS-OCTA). Methods Patients with high myopia (≥ − 6D; axial length ≥ 26.5 mm), moderate myopia (≥ − 3D, < − 6D), and age-matched healthy subjects presenting to the Shanghai General Hospital and Doheny-UCLA Eye Centers were enrolled in this prospective, multicenter study. Any subjects with evidence of macular abnormalities suggestive of pathologic myopia were excluded. SS-OCTA at both sites was performed using a Zeiss PLEX Elite instrument with a 6 × 6 mm scan pattern centered on the fovea. Two repeated volume scans were acquired for ...

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    10. Diversity in optical coherence tomography normative databases: moving beyond race

      Diversity in optical coherence tomography normative databases: moving beyond race

      Normative databases of optical coherence tomography (OCT) metrics, such as retinal nerve fiber layer (RNFL) and macular thickness, are critical to clinical use of OCT imaging. In order to accurately represent the range of normal variation in patient populations, these normative databases must themselves be adequately diverse. Thus far, diversity in OCT normative databases has largely been defined as racial diversity. However, this has largely been based on self-reported “race,” which is inconsistent and generally not scientifically rigorous as a form of categorization. Moreover, there is a great deal of variation even within any single racial group, suggesting that other ...

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    11. Efficacy of Zotarolimus-Eluting Stents in Treating Diabetic Coronary Lesions: An Optical Coherence Tomography Study

      Efficacy of Zotarolimus-Eluting Stents in Treating Diabetic Coronary Lesions: An Optical Coherence Tomography Study

      Background Diabetes mellitus (DM) plays an important role in restenosis and late in-stent thrombosis (ST). The current study using optical coherence tomography (OCT) aims to compare target lesion neointima in patients with or without diabetes after zotarolimus-eluting stent (ZES) treatment. Methods OCT images of 90,212 struts and quantitative coronary angiography (QCA) in 62 patients (32 with DM and 30 without DM) with 69 de novo coronary lesions (34 DM and 35 non-DM) both after ZES implantation and 12 ± 1 month angiographic follow-up were recorded. Patient characteristics, lesion characteristics, clinical outcomes, and OCT findings including neointimal thickness, coverage, malapposition, and ...

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    12. In Vitro Imaging of Animal Tissue with Upconversion Nanoparticles (UCNPs) as a Molecular Probing Agent Using Swept Source Optical Coherence Tomography (SSOCT)

      In Vitro Imaging of Animal Tissue with Upconversion Nanoparticles (UCNPs) as a Molecular Probing Agent Using Swept Source Optical Coherence Tomography (SSOCT)

      Purpose The aim of the current study is to demonstrate the potential of rare earth (RE) based upconversion nanoparticles (UCNPs) as molecular probing agents for non-invasive depth-resolved bioimaging technique, swept-source optical coherence tomography (SSOCT). Methods The Na + doped La 2 O 3 :Er 3+ /Yb 3+ UCNPs were synthesized using a solution combustion route with characterization for emission spectra and morphological study. A custom made SSOCT system was also incorporated for tissue imaging with an A-scan rate of 100 kHz/s, the central wavelength of 1060 nm, an axial and lateral resolution of ~ 4.5 µm and ~ 13 µm in ...

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      Mentions: Raju Poddar
    13. Effects of iron deficiency anemia on peripapillary and macular vessel density determined using optical coherence tomography angiography on children

      Effects of iron deficiency anemia on peripapillary and macular vessel density determined using optical coherence tomography angiography on children

      Purpose To evaluate retinal vascular parameters by optical coherence tomography angiography (OCT-A) in iron deficiency anemia (IDA). Methods Thirty-two patients with IDA (study group) and 30 healthy children (control group) were enrolled in the study. All subjects underwent a complete ocular examination. OCT-A scans were performed in a 6 × 6 mm area centered on the macula. Foveal avascular zone (FAZ), non-flow area (NFA), FAZ perimeter (PERIM), acircularity index (AI) of FAZ, and foveal density (FD) were measured in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). SCP and DCP were also scanned centered on the optic disk. Hemoglobin ...

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    14. Foveal avascular zone area analysis in juvenile-onset type 1 diabetes using optical coherence tomography angiography

      Foveal avascular zone area analysis in juvenile-onset type 1 diabetes using optical coherence tomography angiography

      Purpose Optical coherence tomography angiography (OCTA) was performed on patients with juvenile-onset type 1 diabetes (T1DM) but with no diabetic retinopathy to measure the foveal avascular zone (FAZ) area. Study Design Retrospective single-facility study Methods Twenty-nine patients (58 eyes) with juvenile-onset T1DM were studied. Images (3 mm x 3 mm cube centered on the fovea) were acquired using an OCTA device. Age at examination was 16.1 ± 8.7 years; onset age was 6.4 ± 3.5 years; duration of diabetes was 9.7 ± 8.3 years. Twenty-four age-matched healthy individuals were studied as controls. Results FAZ area was significantly ...

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    15. Examination of corneal deposits in nephropathic cystinosis using in vivo confocal microscopy and anterior segment optical coherence tomography: an age-dependent cross sectional study

      Examination of corneal deposits in nephropathic cystinosis using in vivo confocal microscopy and anterior segment optical coherence tomography: an age-dependent cross sectional study

      Background Presence of corneal cystine crystals is the main ocular manifestation of cystinosis, although controversial findings concerning the corneal layer with the highest density have been reported. The aim of this study was the analysis of the characteristics of crystal arrangement in different corneal layers and the assessment of corneal morphological changes with age. Methods A cross sectional study was carried out in three children and three adults who had nephropathic cystinosis and corneal cystine depositions. All patients underwent a comprehensive ophthalmological examination including best corrected distance visual acuity, slit-lamp examination, in vivo confocal microscopy and anterior segment optical coherence ...

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    16. An assessment of the quality of optical coherence tomography image acquisition

      An assessment of the quality of optical coherence tomography image acquisition

      Optical coherence tomography (OCT) provides excellent image resolution, however OCT optimal acquisition is essential but could be challenging owing to several factors. We sought to assess the quality of OCT pullbacks and identify the causes of suboptimal image acquisition. We evaluated 784 (404 pre-PCI; 380 post-PCI) coronary pullbacks from an anonymized OCT database from our Cardiovascular Imaging Core Laboratory. Imaging of the region-of-interest (ROI—lesion or stented segment plus references) was incomplete in 16.1% pullbacks, caused by pullback starting too proximal (63.7%), inappropriate pullback length (17.1%) and pullback starting too distal (11.4%). The quality of image ...

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    17. Macular Optical Coherence Tomography Angiography in Nephropathic Patients with Diabetic Retinopathy in Iran: A Prospective Case–Control Study

      Macular Optical Coherence Tomography Angiography in Nephropathic Patients with Diabetic Retinopathy in Iran: A Prospective Case–Control Study

      Background Diabetic macular ischemia (DMI) is an important category of diabetic retinopathy (DR) which leads to severe visual loss. Clinically, it is defined by an enlargement of the foveal avascular zone (FAZ) that can be detected by optical coherence tomography angiography (OCTA). Studies have described a relationship between renal disease and these changes in FAZ area. The aim of this study was to compare disturbances in FAZ area in diabetic patients with or without overt nephropathy. Methods Following approval of the ethics committee, we examined diabetic patients with retinopathy. Patients were divided into two groups of DR, namely, with overt ...

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    18. Noninvasive Techniques for Quantification of Contact Dermatitis

      Noninvasive Techniques for Quantification of Contact Dermatitis

      The pathophysiology of contact dermatitis includes specific morphological and physiological changes in the skin as a result of the direct toxic effect of exogenous agents and the subsequent inflammatory cascade. These reactions can be quantified by a variety of noninvasive devices. Classical biophysical methods such as the assessment of transepidermal water loss, stratum corneum hydration, and laser Doppler flowmetry are widely used in the investigation, quantification, and discrimination of irritant and allergic reactions of the skin. Novel in vivo techniques such as in vivo Raman spectroscopy have emerged, and the body of evidence on the skin microstructure is growing. Visualization ...

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    19. Quantitative assessment of the effect of acute anaerobic exercise on macular perfusion via swept-source optical coherence tomography angiography in young football players

      Quantitative assessment of the effect of acute anaerobic exercise on macular perfusion via swept-source optical coherence tomography angiography in young football players

      Aim To evaluate the effect of acute anaerobic exercise on macular perfusion measured by swept-source optical coherence tomography angiography (SS-OCTA) in young football players. Materials and methods Football players with ages between 18 and 20 years were included into the study. After a detailed ophthalmological examination, physiological parameters including height (cm), body weight (kg), body fat percentage (%), systemic blood pressure (BP) (mmHg), hematocrit values (%), oxygen saturation pO 2 (%) and heart rate (bpm) were recorded. Intraocular pressure (IOP) (mmHg) and SS-OCTA using DRI OCT Triton (Topcon, Tokyo, Japan) were measured immediately before and after Wingate test. Results Out of 20, 16 ...

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    20. Compressed Sensing for Optical Coherence Tomography Angiography Volume Generation

      Compressed Sensing for Optical Coherence Tomography Angiography Volume Generation

      Optical coherence tomography angiography (OCTA) is an increasingly popular modality for imaging of the retinal vasculature. Repeated optical coherence tomography (OCT) scans of the retina allow the computation of motion contrast to display the retinal vasculature. To the best of our knowledge, we present the first application of compressed sensing for the generation of OCTA volumes. Using a probabilistic signal model for the computation of OCTA volumes and a 3D median filter, it is possible to perform compressed sensing reconstruction of OCTA volumes while suppressing noise. The presented approach was tested on a ground truth, averaged from ten individual OCTA ...

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    21. The Present and Future of Optical Imaging Technologies in the Clinic: Diagnosis and Therapy

      The Present and Future of Optical Imaging Technologies in the Clinic: Diagnosis and Therapy

      Medical techniques based upon optical imaging technologies are important tools in clinical practice. The use of optical imaging in medical diagnosis is well established, and a large array of techniques are in current use, such as white light endoscopy, autofluorescence imaging, and optical coherence tomography. The applications of these techniques are expanding, and newer imaging technologies are becoming available to address problems and limitations associated with existing methods. Beyond diagnostics, optical imaging is increasingly a useful component of interventional medical procedures, such as image-guided surgery. In procedures such as surgical tumor resection, fluorescence imaging can aid surgeons in improving both ...

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    22. Malapposition of graft-host interface after penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK): an optical coherence tomography study

      Malapposition of graft-host interface after penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK): an optical coherence tomography study

      Backgroud Previous studies of internal graft-host malappositions have not dealt with the precise ways in which each malapposition affected post-penetrating keratoplasty (post-PK) visual outcomes. In this study, we reviewed our post-PK and post-deep anterior lamellar keratoplasty (post-DALK) keratoconic patients and used anterior segment optical coherence tomography (AS-OCT) to evaluate the associations between graft-host interface (GHI) characteristics and visual outcomes. Methods Novel GHI metrics included: mean graft-host touch (GHT), total prevalence of malapposition proportion (Pm), frequency of apposition (F), size of malapposition (Sm), junctional graft thickness (Tg), junctional host thickness (Th) and the absolute value of difference between Tg and Th ...

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      Mentions: Fudan University
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