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    1. Optical Coherence Tomography: Technology and Applications Second Edition (Textbook)

      Optical Coherence Tomography: Technology and Applications Second Edition (Textbook)

      New medical imaging technologies can improve the diagnosis and clinical management of many diseases. Furthermore, advanced imaging also contributes to a better understanding of pathogenesis and therefore to the development of new pharmaceuticals and novel therapies. Thus, imaging plays a critical role in modern medical research and clinical practice. Noninvasive or minimally invasive imaging techniques have revolutionized diagnostic medicine during the last decades, e.g., X-ray computed tomography (CT), magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), radioisotope imaging (position emission tomography (PET)), single-photon emission computed tomography (SPECT), and diffuse optical tomography (DOT). These techniques permit three-dimensional visualization; however ...

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    2. Real-time cancer diagnosis during prostate biopsy: ex vivo evaluation of full-field optical coherence tomography (FFOCT) imaging on biopsy cores

      Real-time cancer diagnosis during prostate biopsy: ex vivo evaluation of full-field optical coherence tomography (FFOCT) imaging on biopsy cores

      Objectives To evaluate the diagnostic accuracy (Acc) of full-field optical coherence tomography (FFOCT) for cancer detection on prostate biopsy. Materials and methods Thirty-eight consecutive patients with elevated PSA and/or suspicious digital rectal examination were prospectively included. For each patient, 1–10 cores were randomly selected and imaged with FFOCT immediately after sampling. The images obtained were de-identified and analyzed by three pathologists blinded to the results of pathological evaluation. The overall average Acc was measured, as well as sensitivity (Se), specificity (Sp), positive and negative predictive values (PPV and NPV). The Acc learning curve was assessed by multivariate logistic ...

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    3. Translating Intravascular Optical Coherence Tomography from a Research to a Clinical Tool

      Translating Intravascular Optical Coherence Tomography from a Research to a Clinical Tool

      Intravascular optical coherence tomography (IVOCT) continues to be a hot topic as a method for studying vulnerable plaque in research laboratories across the globe. It is also growing in popularity as a tool for interventional cardiologists to guide percutaneous coronary intervention (PCI). The power of IVOCT for diagnosis of thin-capped fibroatheromas (TCFAs) has yet to receive mainstream clinical attention due to the fact that clinicians still do not have a protocol to follow if TCFA are identified and that TCFA identification requires extensive training in IVOCT image analysis—it is not yet an automated process. In this review, we will ...

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    4. Optical Coherence Tomography for the Assessment of Coronary Artery Disease

      Optical Coherence Tomography for the Assessment of Coronary Artery Disease

      Angiography remains the gold standard for assessment of atherosclerotic impairment of coronary arteries and for guidance of coronary intervention. Angiography, as a main limitation, only depicts the luminal narrowings caused by coronary plaques, without showing the structures located beneath, such as the atherosclerotic lesions or the vessel wall. Intravascular imaging modalities are currently adopted to circumvent angiographic limitations. Optical coherence tomography (OCT)) is a novel imaging technique that uses infrared lights and can study atherosclerotic plaques and stented segments with extreme accuracy. Compared to intravascular ultrasound (IVUS) , OCT has a much higher resolution; this is at the expense of the ...

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      Mentions: Francesco Prati
    5. Mathematical Methods of Optical Coherence Tomography (Book Chapter)

      Mathematical Methods of Optical Coherence Tomography (Book Chapter)

      In this chapter a general mathematical model of Optical Coherence Tomography (OCT) is presented on the basis of the electromagnetic theory. OCT produces high-resolution images of the inner structure of biological tissues. Images are obtained by measuring the time delay and the intensity of the backscattered light from the sample considering also the coherence properties of light. The scattering problem is considered for a weakly scattering medium located far enough from the detector. The inverse problem is to reconstruct the susceptibility of the medium given the measurements for different positions of the mirror. Different approaches are addressed depending on the ...

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    6. Interventional Cardiology Imaging (Textbook)

      Interventional Cardiology Imaging (Textbook)

      Ever since the establishment of invasive coronary angiography, the limitations of the technique have not gone unnoticed. As a result, multiple invasive imaging modalities have been developed in an attempt to characterize the true severity of coronary artery disease as well as guide the percutaneous coronary interventions. Invasive imaging modalities have included ultrasound, optical, and chemographic technologies. Moreover, physiological assessment of the degree of the coronary blood fl ow has also been performed through fractional and coronary fl ow assessments. This book provides an overview of the current available invasive coronary imaging modalities in an attempt to present a concise ...

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    7. High-definition optical coherence tomography intrinsic skin ageing assessment in women: a pilot study

      High-definition optical coherence tomography intrinsic skin ageing assessment in women: a pilot study

      Several non-invasive two-dimensional techniques with different lateral resolution and measurable depth range have proved to be useful in assessing and quantifying morphological changes in skin ageing. Among these, only in vivo microscopy techniques permit histometric measurements in vivo. Qualitative and quantitative assessment of chronological (intrinsic) age-related (IAR) morphological changes of epidermis, dermo-epidermal junction (DEJ), papillary dermis (PD), papillary-reticular dermis junction and reticular dermis (RD) have been performed by high-definition optical coherence tomography in real time 3-D. HD-OCT images were taken at the internal site of the right upper arm. Qualitative HD-OCT IAR descriptors were reported at skin surface, at epidermal ...

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    8. Metrics of the normal anterior sclera: imaging with optical coherence tomography

      Metrics of the normal anterior sclera: imaging with optical coherence tomography

      Background To investigate anterior scleral thickness in a cohort of healthy subjects using enhanced depth imaging anterior segment optical coherence tomography. Methods Observational case series. The mean scleral thickness in the inferonasal, inferotemporal, superotemporal, and superonasal quadrant was measured 2 mm from the scleral spur on optical coherence tomography in healthy volunteers. Results Fifty-three eyes of 53 Caucasian patients (25 male and 28 female) with an average age of 48.6 years (range: 18 to 92 years) were analysed. The mean scleral thickness was 571 μm (SD 84 μm) in the inferonasal quadrant, 511 μm (SD 80 μm) in the ...

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    9. Enhanced-depth optical coherence tomography for imaging horizontal rectus muscles in Graves’ orbitopathy

      Enhanced-depth optical coherence tomography for imaging horizontal rectus muscles in Graves’ orbitopathy

      Graves’ orbitopathy (GO) is an extraocular eye disease with symptoms ranging from minor discomfort from dry eyes to strabismus and visual loss. One of the hallmarks of active GO is visible hyperemia at the insertion of the extraocular muscles. The aim of the present study was to evaluate the use of enhanced-depth imaging spectral domain anterior segment optical coherence tomography (EDI SD AS-OCT) for detecting pathological changes in horizontal recti muscles of patients with GO. Methods Prospective cross sectional study of 27 eyes. Only women were included. EDI AS-OCT was used to measure the thickness of the tendons of the ...

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    10. Marker-Free Tracking of Facet Capsule Motion Using Polarization-Sensitive Optical Coherence Tomography

      Marker-Free Tracking of Facet Capsule Motion Using Polarization-Sensitive Optical Coherence Tomography

      We proposed and tested a method by which surface strains of biological tissues can be captured without the use of fiducial markers by instead, utilizing the inherent structure of the tissue. We used polarization-sensitive optical coherence tomography (PS OCT) to obtain volumetric data through the thickness and across a partial surface of the lumbar facet capsular ligament during three cases of static bending. Reflectivity and phase retardance were calculated from two polarization channels, and a power spectrum analysis was performed on each a-line to extract the dominant banding frequency (a measure of degree of fiber alignment) through the maximum value ...

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    11. Enhanced-depth optical coherence tomography for imaging horizontal rectus muscles in Graves' orbitopathy

      Enhanced-depth optical coherence tomography for imaging horizontal rectus muscles in Graves' orbitopathy

      Purpose Graves’ orbitopathy (GO) is an extraocular eye disease with symptoms ranging from minor discomfort from dry eyes to strabismus and visual loss. One of the hallmarks of active GO is visible hyperemia at the insertion of the extraocular muscles. The aim of the present study was to evaluate the use of enhanced-depth imaging spectral domain anterior segment optical coherence tomography (EDI SD AS-OCT) for detecting pathological changes in horizontal recti muscles of patients with GO. Methods Prospective cross sectional study of 27 eyes. Only women were included. EDI AS-OCT was used to measure the thickness of the tendons of ...

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    12. Changes in macular layers in the early course of non-arteritic ischaemic optic neuropathy

      Changes in macular layers in the early course of non-arteritic ischaemic optic neuropathy

      Purpose To characterise the changes of the retinal layers in patients with acute anterior ischaemic optic neuropathy (AION), aiming to identify imaging markers for predicting the residual visual function. Methods This was a retrospective review of consecutive patients with unilateral AION from January 2010 to December 2013. We analysed affected eyes at baseline and 1 month later, compared to fellow healthy eyes. Utilising novel image analysis software, we conducted algorithmic segmentation in layers and division in early treatment of diabetic retinopathy study (ETDRS) quadrants of optical coherence tomography images of the macula. Pearson product moment regression analysis of retinal layer ...

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    13. Correlation between visual acuity changes and optical coherence tomography morphological findings in idiopathic epiretinal membranes

      Correlation between visual acuity changes and optical coherence tomography morphological findings in idiopathic epiretinal membranes

      Purpose To analyze the influence of spectral-domain optical coherence tomography (SD-OCT) features on visual acuity changes in patients with idiopathic epiretinal membranes (ERMs). Methods Seventy-nine eyes of 71 patients were included in this study. SD-OCT was performed for all patients; data were collected upon ERM diagnosis and at the final visit. The patients were divided into subgroups based on their SD-OCT features. The initial best corrected visual acuity (BCVA) and changes in BCVA for each subgroup were compared. A multivariate analysis was performed to assess the factors associated with changes in BCVA. Results During a mean follow-up period of 20 ...

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    14. Staging of development in Terrien's degeneration based on corneal curvatures detected by optical coherence tomography

      Staging of development in Terrien's degeneration based on corneal curvatures detected by optical coherence tomography

      Purpose We aimed to explore a new classification system based on the change of focal corneal curvatures and corneal thickness in Terrien’s corneal degeneration with optical coherence tomography. Methods This was a cross-sectional study. Ninety eyes of 59 patients with Terrien’s degeneration were examined with slit lamp biomicroscopy, Orbscan II corneal tomography and the Visante OCT system, and were staged according to Süveges’s classification. Results The ratio of female to male patients was 1.57:1. The ratio of bilateral to unilateral lesions was 1.27:1. The occurrence of bilateral lesion was higher in males ...

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    15. Photopic full-field electroretinography and optical coherence tomography in type 1 diabetic retinopathy

      Photopic full-field electroretinography and optical coherence tomography in type 1 diabetic retinopathy

      Purpose The purpose of this study was to evaluate the role of photopic full-field electroretinography (ERG) and retinal thickness measurements by spectral-domain optical coherence tomography (SD-OCT) in the assessment of disease severity in type 1 diabetic retinopathy. Methods A population-based cohort of 151 patients with type 1 diabetes underwent a complete ophthalmic examination, including photopic full-field ERG and SD-OCT for retinal thickness measurements. Stereoscopic fundus photographs were taken according to the Early Treatment Diabetic Retinopathy Study protocol, and the classification of diabetic retinopathy was based on the International Clinical Diabetic Retinopathy Disease Severity Scale. Associations between photographically determined retinopathy level ...

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    16. Staging of development in Terrien’s degeneration based on corneal curvatures detected by optical coherence tomography

      Staging of development in Terrien’s degeneration based on corneal curvatures detected by optical coherence tomography

      Purpose We aimed to explore a new classification system based on the change of focal corneal curvatures and corneal thickness in Terrien’s corneal degeneration with optical coherence tomography. Methods This was a cross-sectional study. Ninety eyes of 59 patients with Terrien’s degeneration were examined with slit lamp biomicroscopy, Orbscan II corneal tomography and the Visante OCT system, and were staged according to Süveges’s classification. Results The ratio of female to male patients was 1.57:1. The ratio of bilateral to unilateral lesions was 1.27:1. The occurrence of bilateral lesion was higher in males ...

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    17. Atherosclerosis and General Principles of Arterial Imaging

      Atherosclerosis and General Principles of Arterial Imaging

      The imaging of large arteries has expanded during recent years, both for clinical purposes and for research. The technical development has been very impressive. By the use of these modern technologies, it has been possible to achieve a better understanding of atherosclerosis and its morphology and mechanical interactions with the bloodstream. In addition, the imaging of large arteries, especially the aorta, has shed new light on the development of the changes in the arterial media linked to arterial stiffness, increased pulse wave velocity and arterial ageing. In this chapter, these aspects are discussed for atherosclerosis in general and for the ...

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    18. Retinal nerve fiber layer and ganglion cell complex thicknesses measured with spectral-domain optical coherence tomography in eyes with no light perception due to nonglaucomatous optic neuropathy

      Retinal nerve fiber layer and ganglion cell complex thicknesses measured with spectral-domain optical coherence tomography in eyes with no light perception due to nonglaucomatous optic neuropathy

      PURPOSE: To measure retinal nerve fiber layer thickness (RNFLT) and ganglion cell complex thickness (GCCT) in eyes with no light perception due to nonglaucomatous optic neuropathy using spectral-domain optical coherence tomography. METHODS: Fourteen eyes of 14 patients (9 women, 5 men; mean age 56.0 ± 16.6 (standard deviation) years] with no light perception due to optic neuropathy were recruited to this retrospective study. Only clinically stable eyes were included. Eyes were imaged at least 6 months after the onset of the disease. Five patients lost light perception due to traumatic optic neuropathy, four patients had ischemic optic neuropathy, two ...

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    19. Macular morphologic findings on optical coherence tomography after microincision vitrectomy for proliferative diabetic retinopathy

      Macular morphologic findings on optical coherence tomography after microincision vitrectomy for proliferative diabetic retinopathy

      Purpose To investigate macular morphology on spectral-domain optical coherence tomography (SD-OCT) images after microincision vitrectomy for vitreous hemorrhage associated with proliferative diabetic retinopathy (PDR). Methods In this retrospective case series, 69 eyes (57 consecutive patients) that underwent 23-gauge microincision vitrectomy for vitreous hemorrhage due to PDR were investigated. Qualitative and quantitative characteristics on SD-OCT images [central retinal thickness, external limiting membrane (ELM), and the ellipsoid zone, epiretinal membranes involving the fovea, and hyperreflective foci at the fovea] were assessed 6 months postoperatively. Their association with the logarithm of the minimum angle of resolution visual acuity (logMAR VA) was evaluated. Results ...

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    20. Real-life experience after intravitreal ocriplasmin for vitreomacular traction and macular hole: a spectral-domain optical coherence tomography prospective study

      Real-life experience after intravitreal ocriplasmin for vitreomacular traction and macular hole: a spectral-domain optical coherence tomography prospective study

      Purpose To evaluate prospectively the anatomical and functional results after ocriplasmin injection in patients with vitreomacular traction (VMT), or macular hole (MH) combined with VMT, providing the real-life experience of three centers, using spectral domain-optical coherence tomography (SD-OCT). Methods Twenty-four patients with VMT (17 with VMT alone and 7 with an MH combined with VMT) were treated with a single ocriplasmin injection and followed-up prospectively at baseline, day 1, 7, 28 and the last examination of the follow-up for each patient (range: 30–127 days). Best-corrected visual acuity (BCVA) and SD-OCT were performed for patient assessment, while various adverse events ...

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    21. Accurate velocity measurements of boundary-layer flows using Doppler optical coherence tomography

      Accurate velocity measurements of boundary-layer flows using Doppler optical coherence tomography

      Pulsed ultrasound Doppler velocimetry and nuclear magnetic resonance imaging are popular non-invasive measurement methods for flows of opaque fluids. The spatial and temporal resolution of these methods, however, is quite limited, and they lack accuracy, especially close to solid boundaries. In this paper, we show that solution to these problems is achieved by using Doppler optical coherence tomography (DOCT). DOCT provides simultaneous information about the fluid structure and velocity with very high spatial and temporal resolution. For benchmarking of the method we use water as the reference fluid. We show how DOCT gives a very good agreement with theory for ...

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    22. Optimizing flushing parameters in intracoronary optical coherence tomography: an in vivo swine study

      Optimizing flushing parameters in intracoronary optical coherence tomography: an in vivo swine study

      Intracoronary optical frequency domain imaging (OFDI), requires the displacement of blood for clear visualization of the artery wall. Radiographic contrast agents are highly effective at displacing blood however, may increase the risk of contrast-induced nephropathy. Flushing media viscosity, flow rate, and flush duration influence the efficiency of blood displacement necessary for obtaining diagnostic quality OFDI images. The aim of this work was to determine the optimal flushing parameters necessary to reliably perform intracoronary OFDI while reducing the volume of administered radiographic contrast, and assess the influence of flushing media choice on vessel wall measurements. 144 OFDI pullbacks were acquired together ...

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    23. PEGylated Aucore–Agshell Nanorods as Optical Coherence Tomography Signal Nanoamplifiers

      PEGylated Aucore–Agshell Nanorods as Optical Coherence Tomography Signal Nanoamplifiers

      Optimizing contrast enhancement in optical coherence tomography (OCT) is essential for producing specific image signals and realizing its potential use in various biomedical imaging fields besides ophthalmology and cardiology. Using nanoparticles as selective signal nanoamplifiers will be helpful to highlight the lesion sites and identify cancerous changes that are difficult to diagnose currently. In this study, a quantitatively detailed analysis on the improvement of contrast enhancement and penetration depth of Au core –Ag shell nanorods (Au@Ag NRs) as OCT contrast agent was performed. The average A-scan data of the tissue was extracted and investigated. The signal to noise ratio ...

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