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    1. Anterior segment optical coherence tomographic characterisation of keratic precipitate

      Anterior segment optical coherence tomographic characterisation of keratic precipitate

      Background/objectives Anterior segment optical coherence tomography (AS-OCT) can be used to visualise keratic precipitates (KPs) on the corneal endothelium. However, there has been no correlation between characteristic clinical appearances of KPs and AS-OCT morphology. We wished to assess the potential diagnostic role of AS-OCT in patients presenting with inflammatory eye disease and KPs. Subjects/methods Six patients with inflammatory KPs were compared to one patient with infective interface keratitis following Descemet Membrane Endothelial Keratoplasty (DMEK) and one patient with endothelial pigment. AS-OCT was performed in each case and morphological features of the KPs were compared. Reflectivity of KPs was ...

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    2. Optical coherence tomography of the retina in schizophrenia: Inter-device agreement and relations with perceptual function

      Optical coherence tomography of the retina in schizophrenia: Inter-device agreement and relations with perceptual function

      Background Optical coherence tomography (OCT) studies have demonstrated differences between people with schizophrenia and controls. Many questions remain including the agreement between scanners. The current study seeks to determine inter-device agreement of OCT data in schizophrenia compared to controls and to explore the relations between OCT and visual function measures. Methods Participants in this pilot study were 12 individuals with schizophrenia spectrum disorders and 12 age- and sex-matched controls. Spectralis and Cirrus OCT machines were used to obtain retinal nerve fiber layer (RNFL) thickness and macular volume. Cirrus was used to obtain ganglion cell layer + inner plexiform layer (GCL + IPL ...

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    3. Acquisition and Extraction of Surface and Internal Fingerprints from Optical Coherence Tomography through 3D Fully Convolutional Network

      Acquisition and Extraction of Surface and Internal Fingerprints from Optical Coherence Tomography through 3D Fully Convolutional Network

      Optical coherence tomography (OCT) is a non-destructive, high-resolution, and non-invasive imaging technique that has recently been applied to biometric field for three dimensional (3D) fingertip data acquisition. Fingertip volume data contains the epidermis and part of the dermis layers representing the surface fingerprint and internal fingerprint, respectively. As a 3D and under skin feature, internal fingerprint provides much higher anti-counterfeiting capability compared with traditional 2D fingerprints. Furthermore, it is not affected by fingertip conditions such as wet, worn out (old) and small scars/injuries. However, the extraction of surface and internal fingerprints is challenging due to the speckle noise and ...

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    4. Early Diagnostic Value of Optical Coherence Tomography in The Clinical Prediction Model for Optic Nerve Injury in Saddle Space Occupying Patients

      Early Diagnostic Value of Optical Coherence Tomography in The Clinical Prediction Model for Optic Nerve Injury in Saddle Space Occupying Patients

      In this study, 50 patients with anterior ischemic optic neuropathy due to saddle block were selected as the experimental group, and 50 healthy subjects were used as the control group to conduct a study. The best corrected visual acuity examination, optical coherence tomography and visual evoked potential examination were performed on the two groups. The results of the study showed that the majority of patients were middle-aged and older people over the age of 50, but the youngest patients were only 37 years old. After various examinations, it was found that patients with optic nerve injury had a significant reduction ...

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      Mentions: Yan Li
    5. Vitreoretinal interface slab in optical coherence tomography-angiography for detecting diabetic retinal neovascularization

      Vitreoretinal interface slab in optical coherence tomography-angiography for detecting diabetic retinal neovascularization

      Purpose To compare neovascularization (NV) identified in proliferative diabetic retinopathy (PDR) eyes by wide-field swept-source optical coherence tomography angiography (SS-OCTA) using vitreoretinal interface (VRI) slab images, composed by automated and manual segmentation, with that identified by fluorescein angiography (FA). Design Retrospective study. Subjects Forty-two eyes of 30 treatment-naïve PDR patients who visited the outpatient clinic of the Ophthalmology Department of Shinshu University from June 2018 through October 2019. Methods All patients underwent comprehensive ophthalmological examinations, including SS-OCTA and FA. Main Outcome Measures. NV detected by en face SS-OCTA 15 × 15-mm VRI slab images and FA in the same 15 ...

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    6. Quantitative flow reserve virtual stenting and post stenting measurements to predict fractional flow reserve post stenting from the DOCTORS study population

      Quantitative flow reserve virtual stenting and post stenting measurements to predict fractional flow reserve post stenting from the DOCTORS study population

      Background Quantitative flow reserve (QFR) is a computation of fractional flow reserve (FFR) based on angiography without use of a pressure wire. The ability to predict post-PCI FFR using pre-PCI QFR analysis with a virtual PCI and the correlation between post-PCI QFR compared to post-PCI FFR remains unknown. We sought to evaluate the correlations of pre-PCI QFR analysis with virtual PCI called residual QFR and post-PCI QFR compared to post-PCI FFR. Methods From the DOCTORS (Does Optical Coherence Tomography Optimize Results of Stenting) study population; we blindly analyzed residual QFR and post-PCI QFR from angiographies and compared them to post-PCI ...

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    7. Cut-off value of strut-vessel distance for the resolution of acute incomplete stent apposition in the early phase using serial optical coherence tomography after cobalt-chromium everolimus-eluting stent implantation

      Cut-off value of strut-vessel distance for the resolution of acute incomplete stent apposition in the early phase using serial optical coherence tomography after cobalt-chromium everolimus-eluting stent implantation

      Objective The purpose of this study was to identify a cut-off value to predict the resolution of incomplete-stent-apposition (ISA) after cobalt-chromium everolimus-eluting stent (CoCr-EES) implantation at early follow-up. Background To date, appropriate stent apposition at the acute period using intracoronary imaging has been recommended because persistent ISA is considered to be a risk factor for stent thrombosis. We examined the indices for resolving acute ISA. In particular, we determined the cut-off value for strut vessel distance (SV-distance) as visualized by optical coherence tomography (OCT) at 8 months after CoCr-EES implantation. However, the cut-off value of SV-distance for the earlier resolution ...

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    8. Characterization of the calcium component of vulnerable coronary plaque in patients with NSTEMI: Prospective comparison between coronary CT and optical coherence tomography

      Characterization of the calcium component of vulnerable coronary plaque in patients with NSTEMI: Prospective comparison between coronary CT and optical coherence tomography

      Background Acute Coronary Syndrome (ACS) remains a leading cause of mortality worldwide. Several studies have demonstrated a role for Coronary Computed Tomographic Angiography (CCTA) to predict the vulnerability of the plaque. Recent works suggest a role for calcification in this vulnerability. Purpose To assess if the CCTA study of the calcium component of plaques can predict plaque vulnerability defined by intracoronary OCT analysis in patients with non-ST elevation myocardial infarction (NSTEMI). Methods Prospective study of consecutive patients with NSTEMI and elevated high-sensitivity cardiac troponin I level > 50 ng/ml from January to October 2018. CCTA was performed before coronary angiography ...

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    9. Automatic vessel lumen segmentation in optical coherence tomography (OCT) images

      Automatic vessel lumen segmentation in optical coherence tomography (OCT) images

      This paper presents a graph based method to automatically and accurately segment the lumen borders from optical coherence tomography (OCT) images. The proposed method unravels the OCT images from the Cartesian coordinates to polar coordinates so that the segmentation is transferred into a height field delineation problem. In effect, the method imposes a simplistic star shape prior but without the bias towards narrower lumen size. The lumen border is identified as the solution to finding the minimum closed set on a node-weighed, directed graph. In order to cope with both the variability in imaging condition and different forms of image ...

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    10. Beyond Performance Metrics: Automatic Deep Learning Retinal OCT Analysis Reproduces Clinical Trial Outcome

      Beyond Performance Metrics: Automatic Deep Learning Retinal OCT Analysis Reproduces Clinical Trial Outcome

      Purpose To validate the efficacy of a fully-automatic, deep learning-based segmentation algorithm beyond conventional performance metrics by measuring the primary outcome of a clinical trial for macular telangiectasia type 2 (MacTel2) Design Evaluation of diagnostic test or technology Participants 92 eyes from 62 participants with MacTel2 from a phase 2 clinical trial (NCT01949324) randomized to one of two treatment groups Methods The ellipsoid zone (EZ) defect areas were measured on spectral domain optical coherence tomography images of each eye at two time points (Baseline and Month 24) by a fully-automatic, deep learning-based segmentation algorithm. The change in EZ defect area ...

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    11. Use of optical coherence tomography angiography for assessment of microvascular changes in the macula and optic nerve head in hypertensive patients without hypertensive retinopathy

      Use of optical coherence tomography angiography for assessment of microvascular changes in the macula and optic nerve head in hypertensive patients without hypertensive retinopathy

      Purpose To compare optical coherence tomography angiography (OCTA) screening parameters of the macula and optic nerve head (ONH) between healthy volunteers and chronic hypertensive patients without hypertensive retinopathy. Methods This was an observational, cross-sectional study. Fifty-seven chronic hypertensive patients without hypertensive retinopathy (22 men and 35 women) and 40 healthy volunteers (17 men and 23 women), ranging in age from 60 to 70 years, were included in this study. Patients and volunteers were divided into three groups and one eye was selected randomly from each participant. Group A comprised patients who had a history of hypertension for >10 years (n ...

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      Mentions: Optovue
    12. Sensing high frequency sub-nanometer vibrations using optical coherence tomography with real-time profilometry of multiple inner layers

      Sensing high frequency sub-nanometer vibrations using optical coherence tomography with real-time profilometry of multiple inner layers

      A robust technique for vibration sensing using Optical Coherence Tomography is introduced, which can yield nanometer- and sub-nanometer-scale vibration measurements for multiple inner layers simultaneously, even with low signal to noise ratio (SNR) signals from low cost devices. Constructing a camera-based parallel spectral domain optical coherence tomography device with just 40 dB SNR, we demonstrate as proof-of-principle, how our technique can work with vibration amplitudes over three orders of magnitude, from hundreds of picometers to hundreds of nanometers. Our technique is unrestricted by the Nyquist sampling limit. This makes it suitable for measuring amplitudes of even MHz frequency vibrations which ...

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    13. Anterior segment optical coherence tomography scanning protocols and corneal thickness repeatability

      Anterior segment optical coherence tomography scanning protocols and corneal thickness repeatability

      Purpose To examine the influence of anterior segment optical coherence tomography imaging protocols on the intraobserver and intrasession repeatability of epithelial, stromal, and total corneal thickness measurements. Methods Repeated anterior segment optical coherence tomography (AS-OCT) images (Spectralis, Heidelberg) were obtained from 15 adults using single 8.3 mm wide horizontal line scans with an average of 2, 10, 20, 30, 50 and 100 B-scans. Volumetric scans consisting of nine 8.3 mm horizontal line scans encompassing a 1.3 mm vertical region were also captured (with 20 B-scans per line scan). Single point thickness measures (at the normal to the ...

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    14. OCT-Based Management of Nilotinib-Associated CAD in a Patient With Chronic Myeloid Leukemia

      OCT-Based Management of Nilotinib-Associated CAD in a Patient With Chronic Myeloid Leukemia

      Chronic myeloid leukemia (CML) is a myeloproliferative disorder of pluripotent hematopoietic stem cells caused by Bcr-Abl tyrosine kinase, the product of the Philadelphia chromosome. Bcr-Abl tyrosine kinase inhibitors (TKIs) have dramatically improved the prognosis of patients with CML (1). Although w 20% of patients with CML develop intolerance or resistance to the first Bcr-Abl TKI, imatinib mesylate, several second-generation TKIs, including nilotinib, dasatinib, and bosutinib, have overcome this issue (2). However, second-generation Bcr-Abl TKIs are associated with an increased risk of arterial thromboembolic events such as coronary artery disease (CAD), ischemic stroke, and peripheral arterial disease. In particular, nilotinib has ...

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    15. EVALUATION OF POROSITY AND BIOFILM FORMATION IN RELINE RESINS THROUGH OPTICAL COHERENCE TOMOGRAPHY

      EVALUATION OF POROSITY AND BIOFILM FORMATION IN RELINE RESINS THROUGH OPTICAL COHERENCE TOMOGRAPHY

      Objective To evaluate the porosity and adhesion of mixed colony microorganisms in reline resins by means of optical coherence tomography (OCT). Study Design Two commercial brands of reline resins (Soft-Comfort and Coe-Comfort) were used, divided into 2 groups, and 10 samples were made for each group. Samples were submitted to OCT scanning before and after 96 hours inoculation with Candida albicans . The OCT images were composed of 2000 columns and 512 lines, obtained from a commercial model, Callisto SD-OCT (Thorlabs, USA), operating at 930 nm of central wavelength and 7 μm of axial resolution in the air. After the images ...

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    16. Average lens density quantification with swept-source optical coherence tomography: optimized, automated cataract grading technique

      Average lens density quantification with swept-source optical coherence tomography: optimized, automated cataract grading technique

      Purpose To assess a revised version of an objective cataract grading method based on the lens densitometry on swept-source optical coherence tomography (SS-OCT) scans. Setting Rothschild Foundation, Paris, France. Design Prospective case series. Methods All patients seeking a cataract evaluation and consenting to study participation were included. Exclusion criteria were a history of ocular surgery, cornea or retina disorders, and ocular dryness. The average lens densitometry (ALD) was measured on SS-OCT scans (IOLMaster 700) using an algorithm developed with MATLAB software. The ocular scatter index (OSI), measured using a double-pass aberrometer (Optical Quality Analysis System); Pentacam nucleus staging (PNS) score ...

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    17. Cholesterol Crystals are Associated with Carotid Plaque Vulnerability: An Optical Coherence Tomography Study

      Cholesterol Crystals are Associated with Carotid Plaque Vulnerability: An Optical Coherence Tomography Study

      Objective: Vulnerable carotid plaque is associated with cerebrovascular events. Cholesterol crystals are often seen in the atherosclerotic plaques. However, the potential role of cholesterol crystals in carotid plaques destabilization is unknown. We aimed to identify the association between cholesterol crystals and carotid plaque vulnerability. Methods: Optical coherence tomography assessment of carotid plaque was performed in 95 patients. Clinical characteristics and plaque morphology were examined. The differences in plaque characteristics (thrombus, calcification, neovascularization, and macrophage accumulations) and clinical parameters (age, symptom, coronary heart disease, total cholesterol, triglycerides, and C-reactive protein) between patients with or without cholesterol crystals were analyzed with multivariate ...

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    18. Investigation of sputtering target re-deposits by Optical Coherence Tomography and Grazing Incident X-ray Diffraction

      Investigation of sputtering target re-deposits by Optical Coherence Tomography and Grazing Incident X-ray Diffraction

      The sputtering target re-deposit grown by cumulative sputtering has been investigated in this work by studying both fresh and rigorously sputtered zirconium oxide target by Fourier Domain Optical Coherence Tomography (FDOCT), a depth resolved optical imaging modality. The Optical Coherence Tomography (OCT) depth profiles have further been analyzed to extract optical attenuation coefficient of sputtered target surface as well as fresh target surface. Re-deposited sputtered target surface shows larger optical attenuation coefficient in the range of 1.5-4.4 mm −1 as opposed to that of 1.1 mm −1 for fresh ZrO 2 target. The same sputtered target surfaces ...

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      Mentions: K. Divakar Rao
    19. Optical coherence tomography of patients with Parkinson’s disease and progressive supranuclear palsy

      Optical coherence tomography of patients with Parkinson’s disease and progressive supranuclear palsy

      Objectives To determine if Parkinson’s disease (PD) and progressive supranuclear palsy (PSP) differed on retinal measurements using optical coherence tomography (OCT). Patients and methods In a prospective, controlled, cross-sectional cohort study, we recruited patients with PD or PSP for more than three years, as well as control subjects. We measured peripapillary retinal nerve fiber layer (RNFL) thickness and macular volume using spectral-domain OCT. The association between these OCT measures and the disease characteristics of duration and disability were examined using a linear mixed effect model. Results We analyzed eyes from n = 12 PD patients, n = 11 PSP patients, and ...

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    20. Optical coherence tomography of retinal and choroidal layers in patients with familial hypercholesterolaemia treated with lipoprotein apheresis

      Optical coherence tomography of retinal and choroidal layers in patients with familial hypercholesterolaemia treated with lipoprotein apheresis

      Purpose Detect and quantify morpho-functional alterations of the retina and choroid in patients affected by familial hypercholesterolemia (FH) treated with lipoprotein apheresis (LA) using optic coherence tomography (OCT) and optic coherence tomography-angriography (OCTA). Design Observational study. Subjects To be diagnosed: A group of 20 patients (40 eyes) being clinically and genetically diagnosed as FH and under treatment (FH-Group)”, for at least 2 years, was compared to a control group of 20 healthy subjects (40 eyes), with a normal lipid profile and no ocular disease (CT-Group). Methods Participants were studied with the slit lamp, binocular indirect fundoscopy, OCT and OCTA. Main ...

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    21. Deep-Learning System Detects Neoplasia in Patients With Barrett’s Esophagus With Higher Accuracy Than Endoscopists in a Multi-Step Training and Validation Study with Benchmarking

      Deep-Learning System Detects Neoplasia in Patients With Barrett’s Esophagus With Higher Accuracy Than Endoscopists in a Multi-Step Training and Validation Study with Benchmarking

      Background & Aims We aimed to develop and validate a deep-learning computer-aided detection (CAD) system, suitable for use in real time in clinical practice, to improve endoscopic detection of early neoplasia in patients with Barrett’s esophagus (BE). Methods We developed a hybrid ResNet-UNet model CAD system using 5 independent endoscopy datasets. We performed pre-training using 494,364 labelled endoscopic images collected from all intestinal segments. Then, we used 1704 unique esophageal high-resolution images of rigorously confirmed early-stage neoplasia from patients with BE, and non-dysplastic BE, derived from 669 patients. System performance was assessed using datasets 4 and 5. Dataset 5 ...

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    22. Intravascular ultrasound or optical coherence tomography-defined anatomic severity and hemodynamic severity assessed by coronary physiologic indices

      Intravascular ultrasound or optical coherence tomography-defined anatomic severity and hemodynamic severity assessed by coronary physiologic indices

      Introduction and objectives Fractional flow reserve or instantaneous wave-free ratio has become a standard criterion for revascularization . We sought to evaluate the association between intravascular ultrasound (IVUS) or optical coherence tomography (OCT)-derived quantitative plaque characteristics and the severity of physiologic stenosis. Methods A total of 365 stenoses from 330 patients were evaluated. The association between IVUS or OCT-derived parameters and resting physiologic indices (instantaneous wave-free ratio, resting full-cycle ratio, and diastolic pressure ratio) and fractional flow reserve were explored. Results Among the total number of lesions, 50.7% and 58.1% showed an instantaneous wave-free ratio ≤ 0.89 and ...

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    23. Optical coherence tomography in the assessment of cutaneous cancer margins of the face: an immediate ex vivo study

      Optical coherence tomography in the assessment of cutaneous cancer margins of the face: an immediate ex vivo study

      Background The assessment of cutaneous cancer margins intra-operatively or in the immediate postoperative phase can guide the operator into achieving clearer margins. Achieving a clear (tumour-free) margins following surgery is an essential factor that can reduce morbidity and disfigurement. The aim of present study was to determine the accuracy of optical coherence tomography in assessing cutaneous cancer margins of the face. Materials and Methods The excised tissue specimens that were examined, in this study, were acquired from 70 patients with 70 facial cancer lesions, with no nodal disease. Forty lesions were basal cell carcinomas (150 margins; 27 tumour positive) and ...

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