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    1. 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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    2. 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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    3. 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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    4. 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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    5. Identification of multi-dimensional thread geometry using depth-resolved swept-source optical coherence tomography for assessment of dental implant fabrication

      Identification of multi-dimensional thread geometry using depth-resolved swept-source optical coherence tomography for assessment of dental implant fabrication

      The geometrical characteristics of dental implants, such as thread depth and width, facing angle, pitch, and surface roughness, are important to assess their stability and osseointegration after implant surgery. Herein, we demonstrate the potential use of depth-resolved swept-source optical coherence tomography (SS-OCT) to assess the structural quality of widely used dental implants. The implemented SS-OCT system was centered at a wavelength of 1300 nm with a 100 nm full-width at half-maximum. Four dental implants with different structural formations fabricated using either titanium or ceramic were visualized. Qualitative assessments were performed using boundary flattening with an amplitude-profiling algorithm to emphasize and ...

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    6. Spectral Domain Optical Coherence Tomography Findings in Myotonic Dystrophy

      Spectral Domain Optical Coherence Tomography Findings in Myotonic Dystrophy

      The purpose of the study is to evaluate retinal involvement in a cohort of patients affected by Myotonic Dystrophy type 1 (DM1). 61 eyes of 31 patients with genetically proven diagnosis of DM1 and 40 eyes of 20 healthy age- and gender- matched subjects were enrolled. All patients underwent complete ophthalmologic examination including best-corrected visual acuity, intraocular pressure measurement, fundoscopy, fundus autofluorescence, infrared imaging and spectral-domain optical coherence tomography (SD-OCT) with central macular thickness (CMT) measurement. DM1 patients showed statistically significant higher CMT values than controls. In the DM1 group, butterfly (14.8%) and reticular (13.1%) pigment abnormalities were ...

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    7. Percutaneous Treatment of Long Coronary Aneurysms: Novel Technique for Increased Efficacy and Safety

      Percutaneous Treatment of Long Coronary Aneurysms: Novel Technique for Increased Efficacy and Safety

      Although covered stents have been available for percutaneous treatment of coronary aneurysms, patients with longer aneurysmal segments have been difficult to treat with covered stents. The authors describe a case of a right coronary artery aneurysm with an angiographically estimated length exceeding 30 mm treated percutaneously using covered stents and conventionally available hardware. ( Level of Difficulty: Advanced. )

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    8. Serial OCT Imaging of Multiple Woven-Appearing Lesions in a Single Patient Demonstrating Long-Term Clinical Stabilit

      Serial OCT Imaging of Multiple Woven-Appearing Lesions in a Single Patient Demonstrating Long-Term Clinical Stabilit

      We report the case of a 58-year-old man with a history of myocardial infarction presenting with chest pain. Serial coronary artery optical coherence tomography over a 3-year period showed multiple woven-appearing lesions without progression, indicating that this type of lesion is potentially stable. ( Level of Difficulty: Advanced. )

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    9. Sectorwise Visual Field Simulation Using Optical Coherence Tomographic Angiography Nerve Fiber Layer Plexus Measurements in Glaucoma

      Sectorwise Visual Field Simulation Using Optical Coherence Tomographic Angiography Nerve Fiber Layer Plexus Measurements in Glaucoma

      Purpose To simulate 24-2 visual field (VF) using optical coherence tomographic angiography (OCTA) for glaucoma evaluation. Design Cross-sectional study. Methods One eye each of 39 glaucoma and 31 age-matched normal participants was scanned using 4.5-mm OCTA scans centered on the disc. The peripapillary retinal nerve fiber layer plexus capillary density (NFLP_CD, %area) was measured. The NFLP_CD and 24-2 VF maps were divided into 8 corresponding sectors using an extension of Garway-Heath scheme. Results Sector NFLP_CD was transformed to a logarithmic dB scale and converted to sector simulated VF deviation maps. Comparing simulated and actual 24-2 VF maps, the worst ...

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    10. Efficacy of Spectroscopic Optical Coherence Tomography (sOCT) for instantaneous study of nitrilase enzyme kinetics

      Efficacy of Spectroscopic Optical Coherence Tomography (sOCT) for instantaneous study of nitrilase enzyme kinetics

      We present monitoring of nitrilase enzyme assay in real-time by means of Spectroscopic Optical Coherence Tomography (sOCT). Combination of principal component analysis (PCA) algorithm with Swept Source Optical Coherence Tomography (SSOCT), to extract the absorption spectra of the sample, termed as sOCT. Spectroscopic information of nitrilase enzyme obtained from sOCT is used to investigate dynamic enzyme kinetic reactions. Different principle components give complete information regarding the composition of the samples. Further, Fourier Transform Infrared Spectroscopy (FTIR) analysis has been also performed to validate the PCA absorption spectra. Samples were prepared in controlled condition and evaluated at a regular time interval ...

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    11. Intravascular Polarimetry in Patients With Coronary Artery Disease

      Intravascular Polarimetry in Patients With Coronary Artery Disease

      Objectives The aims of this first-in-human pilot study of intravascular polarimetry were to investigate polarization properties of coronary plaques in patients and to examine the relationship of these features with established structural characteristics available to conventional optical frequency domain imaging (OFDI) and with clinical presentation. Background Polarization-sensitive OFDI measures birefringence and depolarization of tissue together with conventional cross-sectional optical frequency domain images of subsurface microstructure. Methods Thirty patients undergoing polarization-sensitive OFDI (acute coronary syndrome, n = 12; stable angina pectoris, n = 18) participated in this study. Three hundred forty-two cross-sectional images evenly distributed along all imaged coronary arteries were classified into ...

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    12. Spectral domain - Optical coherence tomography (SD-OCT) as a monitoring tool for alterations in mouse lenses

      Spectral domain - Optical coherence tomography (SD-OCT) as a monitoring tool for alterations in mouse lenses

      The eye lens displayes a variety of phenotypes in the wake of genetical modifications or environmental influences. Therefore, a high-resolution in vivo imaging method for the lens is desirable. Optical coherence tomography (OCT) has become a powerful imaging tool in ophthalmology, especially for retinal imaging in small animal models such as mice. Here, we demonstrate an optimized approach specifically for anterior eye segment imaging with spectral domain OCT (SD-OCT) on several known murine lens cataract mutants. Scheimpflug and histological section images on the same eye were used in parallel to assess the observed pathologies. With SD-OCT images, we obtained detailed ...

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    13. Optical coherence tomography angiography assessment of retinal microvascular changes in diabetic eyes in an urban safety-net hospital

      Optical coherence tomography angiography assessment of retinal microvascular changes in diabetic eyes in an urban safety-net hospital

      PURPOSE To determine whether quantitative optical coherence tomography angiography (OCTA) parameters can be used to distinguish among eyes at various stages of diabetic retinopathy (DR) in an urban safety-net hospital population. DESIGN Prospective cross-sectional study PARTICIPANTS 329 eyes from 329 patients were included in this study; 90 nondiabetic patients, 170 diabetic patients without retinopathy, 57 diabetes with mild to moderate NPDR, and 12 diabetes with severe NPDR to PDR. METHODS Patients underwent OCTA imaging and ultra-widefield fundus photography at Zuckerberg San Francisco General Hospital and Trauma Center between April and October 2018. For participants with diabetes, imaging was classified according ...

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      Mentions: UCSF
    14. Human versus Machine: Comparing a Deep Learning Algorithm to Human Gradings for Detecting Glaucoma on Fundus Photographs

      Human versus Machine: Comparing a Deep Learning Algorithm to Human Gradings for Detecting Glaucoma on Fundus Photographs

      Abstract Purpose To compare the diagnostic performance of human gradings versus predictions provided by a machine-to-machine (M2M) deep learning (DL) algorithm trained to quantify retinal nerve fiber layer (RNFL) damage on fundus photographs. Design Evaluation of a machine learning algorithm. Methods A M2M DL algorithm trained with RNFL thickness parameters from spectral-domain optical coherence tomography was applied to a subset of 490 fundus photos of 490 eyes of 370 subjects graded by two glaucoma specialists for the probability of glaucomatous optical neuropathy (GON), and estimates of cup-to-disc (C/D) ratios. Spearman correlations with standard automated perimetry (SAP) global indices were ...

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    15. Intraoperative OCT-Assisted Retinal Detachment Repair in the DISCOVER Study: Impact and Outcomes

      Intraoperative OCT-Assisted Retinal Detachment Repair in the DISCOVER Study: Impact and Outcomes

      Purpose The purpose of this study is to evaluate intraoperative OCT (iOCT) utility and outcomes during retinal detachment (RD) repair. Design The DISCOVER intraoperative OCT study is a prospective IRB-approved study. Subjects Subjects in the DISCOVER study undergoing surgical repair for RD. Methods This was a post-hoc analysis of eyes in the DISCOVER study undergoing surgical repair for retinal detachments. Inclusion criteria included iOCT following perfluorocarbon liquid (PFO) placement and at least 6 months follow-up. Exclusion criteria included severe retinal pathology unrelated to RD. Surgeons completed standardized questionnaires after each case evaluating the iOCT instrument’s utility. Functional and surgical ...

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    16. Paediatric optical coherence tomography normative databases: A real need

      Paediatric optical coherence tomography normative databases: A real need

      Introduction Optical coherence tomography (OCT) has become an essential tool in paediatric ophthalmology. However, none of the currently available OCT devices include any kind of normative database for the paediatric population, which can lead to important interpretation errors. Objective To review the paediatric OCT normative databases. Material and methods The applications and implications of the use of paediatric OCT normative databases are reviewed. Results The paediatric normative databases that have been published so far in scientific literature with different OCT devices for Spanish and European population are presented. Conclusions The knowledge and interpretation of paediatric OCT normative databases in our ...

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    17. Ultra-Widefield Protocol Enhances Automated Classification of Diabetic Retinopathy Severity with Optical Coherence Tomography Angiography

      Ultra-Widefield Protocol Enhances Automated Classification of Diabetic Retinopathy Severity with Optical Coherence Tomography Angiography

      Purpose To assess the diagnostic utility of retinal nonperfusion to classify eyes based on diabetic retinopathy (DR) severity on optical coherence tomography angiography (OCTA). To determine whether wider field of view (FOV) OCTA protocols enhance the diagnostic utility of retinal nonperfusion in the classification of DR severity. Design Retrospective cross-sectional study Subjects Diabetic patients undergoing ultra-widefield OCTA imaging at one academic retina practice Methods Ultra-widefield OCTA images with 100 degree FOV were obtained from 60 eyes. Eyes were grouped as diabetes without retinopathy (DWR), nonproliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR). The ratio of nonperfusion (RNP) was expressed ...

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    18. Relationship Of Geographic Altitude With Foveal Avascular Zone Metrics And Vascular Density Values Assessed By Optical Coherence Tomography Angiography

      Relationship Of Geographic Altitude With Foveal Avascular Zone Metrics And Vascular Density Values Assessed By Optical Coherence Tomography Angiography

      Objective To evaluate variations in vascular density (VD) and foveal avascular zone (FAZ) metrics in relation to geographical altitude in healthy subjects from six different Latin American cities. Design Cross-sectional. Subjects Healthy volunteers from six Latin American cities. Methods One hundred eighty-five volunteers were recruited over a 3-month period. The RTVue-XR Avanti system was used along with split-spectrum amplitude-decorrelation angiography (SSADA) software 7.1. to obtain optical coherence tomography angiography (OCTA) images from 3×3 mm 2 and 6×6 mm 2 Angioscans centered on the fovea for both the superficial capillary plexus (SCP) and the deep capillary plexus (DCP ...

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    19. At-line Validation of Optical Coherence Tomography as In-line/At-line Coating Thickness Measurement Method

      At-line Validation of Optical Coherence Tomography as In-line/At-line Coating Thickness Measurement Method

      Optical Coherence Tomography (OCT) is a promising technology for monitoring of pharmaceutical coating processes. However, the pharmaceutical development and manufacturing require a periodic validation of the sensor’s accuracy. For this purpose, we propose polyethylene terephthalate (PET) films as a model system, which can be periodically measured during manufacturing coating monitoring via OCT. This study proposes a new approach addressing the method validation requirement in the pharmaceutical industry and presents results for complementary methods. The methods investigated include direct measurement of the layer thickness using a micrometer gauge as reference, X-ray micro computed tomography, transmission and reflectance terahertz pulsed imaging ...

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    20. Topography and pachymetry maps for mouse corneas using optical coherence tomography

      Topography and pachymetry maps for mouse corneas using optical coherence tomography

      The majority of the eye's refractive power lies in the cornea, and pathological changes in its shape can affect vision. Small animal models offer an unparalleled degree of control over genetic and environmental factors that can help elucidate mechanisms of diseases affecting corneal shape. However, there is not currently a method to characterize the corneal shape of small animal eyes with topography or pachymetry maps, as is done clinically for humans. We bridge this gap by demonstrating methods using optical coherence tomography (OCT) to generate the first topography and pachymetry (thickness) maps of mouse corneas. Radii of curvature acquired ...

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    21. Assessing internal fouling during microfiltration optical coherence tomography and evapoporometry

      Assessing internal fouling during microfiltration optical coherence tomography and evapoporometry

      The internal fouling of membranes is typically presumed and inferred, but the direct characterization of representative samples is challenging. This study targeted to assess internal fouling using the Optical Coherence Tomography (OCT) and Evapoporometry (EP) techniques for real-time monitoring during filtration and off-line measurement of the pore size distributions (PSDs) of the fouled membranes, respectively. The results were validated by atomic force microscopy (AFM) measurements and also the three-mechanism fouling model. The foulant used was the well-studied bovine serum albumin (BSA), while the membranes were three commercially available polymeric microfiltration membranes with similar nominal pore sizes and porosities. Although the ...

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    22. Evaluation of foveal avascular zone and capillary plexus in smokers using optical coherence tomography angiography

      Evaluation of foveal avascular zone and capillary plexus in smokers using optical coherence tomography angiography

      Purpose To evaluate the macular microvasculature in smokers in comparison to healthy subjects using optical coherence tomography angiography (OCTA). Methods Fifty chronic, regular smokers and 50 healthy non-smokers, as a control group, were recruited for the study. Foveal avascular zone (FAZ) area (mm 2 ) and vessel density (VD) (%) in the superficial (SCP) and deep capillary plexus (DCP) were evaluated. Results FAZ area was 0.424 ± 0.100 mm 2 in the smoker group and 0.333 ± 0.093 mm 2 in the non-smoking control group ( P = 0.002). The deep foveal VD was 31.76 ± 6.33% in the smoker ...

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