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    1. Spectrally Encoded Coherence Tomography and Reflectometry (SECTR): simultaneous en face and cross-sectional imaging at 2 gigapixels-per-second

      Spectrally Encoded Coherence Tomography and Reflectometry (SECTR): simultaneous en face and cross-sectional imaging at 2 gigapixels-per-second

      Non-invasive biological imaging is crucial for understanding in vivo structure and function. Optical coherence tomography (OCT) and reflectance confocal microscopy are two of the most widely used optical modalities for exogenous contrast-free high-resolution three-dimensional imaging in non-fluorescent scattering tissues. However, sample motion remains a critical barrier to raster-scanned acquisition and reconstruction of wide-field anatomically accurate volumetric datasets. We introduce spectrally encoded coherence tomography and reflectometry (SECTR), a high-speed multimodality system for simultaneous OCT and spectrally-encoded reflectance (SER) imaging. SECTR utilizes a robust system design consisting of shared optical relays, scanning mirrors, swept-laser, and digitizer to achieve the fastest reported in ...

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    2. An overview of methods to mitigate artifacts in optical coherence tomography imaging of the skin

      An overview of methods to mitigate artifacts in optical coherence tomography imaging of the skin

      Background Optical coherence tomography (OCT) of skin delivers three-dimensional images of tissue microstructures. Although OCT imaging offers a promising high-resolution modality, OCT images suffer from some artifacts that lead to misinterpretation of tissue structures. Therefore, an overview of methods to mitigate artifacts in OCT imaging of the skin is of paramount importance. Speckle, intensity decay, and blurring are three major artifacts in OCT images. Speckle is due to the low coherent light source used in the configuration of OCT. Intensity decay is a deterioration of light with respect to depth, and blurring is the consequence of deficiencies of optical components ...

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    3. In-line optical fiber metallic mirror reflector for monolithic common path optical coherence tomography probes

      In-line optical fiber metallic mirror reflector for monolithic common path optical coherence tomography probes

      Background and Objectives Endoscopic optical coherence tomography probes suffer from various artifacts due to dispersion imbalance and polarization mismatch between reference and sample arm light. Such artifacts can be minimized using a common path approach. In this work, we demonstrate a miniaturized common path probe for optical coherence tomography using an inline fiber mirror. Materials and Methods A common path optical fiber probe suitable for performing high-resolution endoscopic optical coherence tomography imaging was developed. To achieve common path functionality, an inline fiber mirror was fabricated using a thin gold layer. A commercially available swept source engine was used to test ...

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    4. Transverse partial stent ablation with rotational atherectomy for suboptimal culotte technique in left main stem bifurcation

      Transverse partial stent ablation with rotational atherectomy for suboptimal culotte technique in left main stem bifurcation

      Longitudinal rotational atherectomy of metal struts is well described as bail-out strategy to treat undilatable instent restenosis. Ablation of metal stent struts jailing the ostium of a major side branch in a coronary bifurcation is not described. In the current report, we describe a case of “transverse” rotational atherectomy to treat a failure of culotte stenting in a left main stem bifurcation. We document for the first time in vivo and in man the effect of this strategy using optical coherence tomography.

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    5. Ganglion cell-inner plexiform layer and retinal nerve fibre layer changes within the macula in retinitis pigmentosa: a spectral domain optical coherence tomography study

      Ganglion cell-inner plexiform layer and retinal nerve fibre layer changes within the macula in retinitis pigmentosa: a spectral domain optical coherence tomography study

      Purpose To investigate how macular ganglion cell-inner plexiform layer (GCIPL) and retinal nerve fibre layer (RNFL) thicknesses within the macula change with retinitis pigmentosa (RP) severity. Methods Spectral domain optical coherence tomography (SD-OCT) was used to examine 177 patients with RP and 177 normal controls. An optical coherence tomography (OCT) line scan was used to grade RP severity. Retinitis pigmentosa (RP) was categorized as more advanced if there was no identifiable inner segment ellipsoid (ISe) band (NISE) and as less advanced if an ISe band could be identified and peripheral loss of ISe was apparent (IISE). Ganglion cell-inner plexiform layer ...

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    6. Thickness mapping of individual retinal layers and sectors by Spectralis SD-OCT in Autosomal Dominant Optic Atrophy

      Thickness mapping of individual retinal layers and sectors by Spectralis SD-OCT in Autosomal Dominant Optic Atrophy

      Purpose To assess layer- and location-specific retinal thickness deficits in autosomal dominant optic atrophy (ADOA) using Spectralis SD-OCT. Methods This cross-sectional study included 41 ADOA patients with OPA1 exon 28 (2826delT) mutation [age, 8.6–83.5 years; best-corrected visual acuity (BCVA), 8–89 Early Treatment Diabetic Retinopathy Study (ETDRS) letters] and 55 mutation-free first-degree relatives as healthy controls (age, 8.9–68.7; BCVA, 80–99). Participants underwent routine examination and optical coherence tomography (OCT) with segmentation of the whole retina, inner retinal layers (IRL) and outer retinal layers (ORL). Individual segmentation was performed of the perifoveal retinal nerve ...

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    7. Optical coherence tomography for margin definition of basal cell carcinoma before micrographic surgery—recommendations regarding the marking and scanning technique

      Optical coherence tomography for margin definition of basal cell carcinoma before micrographic surgery—recommendations regarding the marking and scanning technique

      Background/purpose Mohs Micrographic Surgery (MMS) is the preferred therapeutic treatment for high-risk basal cell carcinoma (BCC). Optical Coherence Tomography (OCT) is a non-invasive imaging technique that enables the diagnosis of BCC. We thought to determine the margins of BCCs with OCT, prior to MMS, to reduce the number of surgical steps. Methods Different permanent markers were tested on the skin regarding line width, resistance against disinfection and brightness in the OCT image. The visible tumor margins of BCCs were defined by dermoscopy, adding a safety margin of 2 mm and labeled using the selected pen, causing a signal shadow ...

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    8. Optical coherence tomography: An efficient imaging method for the visualization of human epidermis orientation

      Optical coherence tomography: An efficient imaging method for the visualization of human epidermis orientation

      Recently, it has been shown that epidermal sheets taken from suction blisters are very appropriate skin samples for Multi-Photon (MP) microscopy. However, we observed that image quality was much better when the sample was visualized through the basale side. Thus, the epidermis orientation needs to be controlled before MP imaging. We observed that the use of standard laboratory binoculars led to a high rate of false results. In this context, we showed that optical coherence tomography provided clear images of the epidermis orientation without loss of sample integrity and thus represents an effective technique before slide sealing and MP analysis.

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    9. In vivo imaging of the internal nasal valve during different conditions using optical coherence tomography

      In vivo imaging of the internal nasal valve during different conditions using optical coherence tomography

      Objective Previously, we proposed long-range optical coherence tomography (LR-OCT) to be an effective method for the quantitative evaluation of the nasal valve geometry. Here, the objective was to quantify the reduction in the internal nasal valve angle and cross-sectional area that results in subjective nasal airway obstruction and to evaluate the dynamic behavior of the valve during respiration using LR-OCT. Methods For 16 healthy individuals, LR-OCT was performed in each naris during: 1) normal respiration, 2) peak forced inspiration, 3) lateral nasal wall depression (to the onset of obstructive symptoms), and 4) after application of a topical decongestant. The angle ...

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    10. Visibility of Fiducial Markers used for Image-Guided Radiation Therapy on Optical Coherence Tomography for Registration with CT: an Esophageal Phantom Study

      Visibility of Fiducial Markers used for Image-Guided Radiation Therapy on Optical Coherence Tomography for Registration with CT: an Esophageal Phantom Study

      Purpose Optical coherence tomography (OCT) is of interest to visualize microscopic esophageal tumor extensions to improve tumor delineation for radiation therapy (RT) planning. Fiducial marker placement is a common method to ensure target localization during planning and treatment. Visualization of these fiducial markers on OCT permits integrating OCT and computed tomography (CT) images used for RT planning via image registration. We studied the visibility of 13 (8 types) commercially available solid and liquid fiducial markers in OCT images at different depths using dedicated esophageal phantoms and evaluated marker placement depth in clinical practice. Materials and Methods We designed and fabricated ...

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    11. Optical coherence tomography guided carotid artery stent procedure: technique and potential applications

      Optical coherence tomography guided carotid artery stent procedure: technique and potential applications

      Objectives To (1) present a guide on how to perform optical coherence tomography (OCT) in carotid artery stenting (CAS), to (2) highlight several instructive cases illustrating OCT-guidance as an interventional strategy, and to (3) present the largest case-series of OCT-guided CAS performed in North America, demonstrating its feasibility as an imaging modality in this setting. Background OCT is an intravascular imaging method that captures images with an axial resolution 10 times higher than intravascular ultrasound. OCT has proven to be a useful modality in coronary angiography and may have similar applications in evaluating carotid atherosclerotic disease. Methods We compared our ...

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    12. Canine central corneal thickness measurements via Pentacam-HR®, optical coherence tomography (Optovue iVue®), and high-resolution ultrasound biomicroscopy

      Canine central corneal thickness measurements via Pentacam-HR®, optical coherence tomography (Optovue iVue®), and high-resolution ultrasound biomicroscopy

      Objective To compare central corneal thickness (CCT) values in canine eyes using Pentacam-HR ® Scheimpflug imaging (Pentacam), Optovue ® iVue spectral-domain optical coherence tomography (SD-OCT), and high-resolution ultrasound biomicroscopy (UBM) and generate normative canine Pentacam CCT values. Animals studied Twenty-four client-owned dogs (37 eyes) with nondiseased cornea(s) presenting to the Colorado State University Veterinary Teaching Hospital. Procedures Corneal images were acquired via Pentacam, SD-OCT, and UBM in the listed order. Machine-calculated values of CCT from Pentacam and SD-OCT were compared to operator-measured values from UBM. Bland–Altman analysis was performed to evaluate agreement between instruments. Results Mean CCT ± SD measured by ...

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      Mentions: Optovue
    13. An optical coherence tomography study of neointimal morphology and strut coverage at different time intervals from implantation of biodegradable polymer-coated sirolimus-eluting stents

      An optical coherence tomography study of neointimal morphology and strut coverage at different time intervals from implantation of biodegradable polymer-coated sirolimus-eluting stents

      Objectives The aim of the study was to capture the evolution of neointima after implantation of a biodegradable polymer–coated, sirolimus–eluting, cobalt–chromium coronary stent system (BP-DES). Background Optical coherence tomography (OCT) suggests that in-stent neointimal morphology influences clinical outcomes after DES implantation. Methods Sixty patients treated with single BP-DES implantation were examined by quantitative coronary angiography (QCA) and OCT at 3, 6, and 12-month follow-up. Results Median late lumen loss by QCA (mm) was 0.04 (IQR 0, 0.08), 0.17 (IQR 0, 0.32), and 0.14 (IQR 0.07, 0.31) at 3, 6, and ...

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    14. Retinal pulse wave velocity measurement using spectral-domain optical coherence tomography

      Retinal pulse wave velocity measurement using spectral-domain optical coherence tomography

      The human eyes provide a natural window for noninvasive measurement of the pulse wave velocity (PWV) of small arteries. By measuring the retinal PWV, the stiffness of small arteries can be assessed, which may better detect early vascular diseases. Therefore, retinal PWV measurement has attracted increasing attention. In this study, a jump-scanning method was proposed for non-invasive measurement of retinal PWV using spectral-domain OCT. The jump-scanning method uses the phase-resolved Doppler OCT to obtain the pulse shapes. To realize PWV measurement, the jump-scanning method extracts the transit time of the pulse wave from an original OCT scanning site to another ...

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    15. Microvasculature dropout detected by the optical coherence tomography angiography in nonarteritic anterior ischemic optic neuropathy

      Microvasculature dropout detected by the optical coherence tomography angiography in nonarteritic anterior ischemic optic neuropathy

      Objective To investigate microcirculation characteristics of peripapillary superficial retina and optic disc in eyes with nonarteritic anterior ischemic optic neuropathy (NAION) using optical coherence tomography angiography (OCTA). Methods Forty-one eyes of 30 NAION patients and 30 eyes of 30 normal subjects were evaluated with OCTA (AngioVue, Optovue). The whole vessel density, inside disc vessel density, peripapillary vessel density, and vessel densities based on the sectorial division in the nerve head mode peripapillary superficial retina and RPC mode optic disc were measured respectively. Results In the NAION group, vessel densities in both the peripapillary superficial retina and optic disc were significant ...

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    16. Characterizing biochemical and morphological variations of clinically relevant anatomical locations of oral tissue in vivo with hybrid Raman spectroscopy and optical coherence tomography technique

      Characterizing biochemical and morphological variations of clinically relevant anatomical locations of oral tissue in vivo with hybrid Raman spectroscopy and optical coherence tomography technique

      his study aims to characterize biochemical and morphological variations of the clinically relevant anatomical locations of in vivo oral tissue (i.e., alveolar process, lateral tongue, and floor of the mouth) by using hybrid Raman spectroscopy (RS) and optical coherence tomography (OCT) technique. A total of 1049 in vivo fingerprint (FP: 800-1800 cm -1 ) and high wavenumber (HW: 2800-3600 cm -1 ) Raman spectra were acquired from different oral tissue (alveolar process=331; lateral tongue=339, and floor of mouth=379) of 26 normal subjects in the oral cavity under the OCT imaging guidance. The total Raman dataset were split into ...

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    17. Investigating the healing mechanisms of an angiogenesis-promoting topical treatment for diabetic wounds using multimodal microscopy

      Investigating the healing mechanisms of an angiogenesis-promoting topical treatment for diabetic wounds using multimodal microscopy

      Impaired skin wound healing is a significant co-morbid condition of diabetes that is caused by poor microcirculation, among other factors. Studies have shown that angiogenesis, a critical step in the wound healing process in diabetic wounds, can be promoted under hypoxia. In this study, an angiogenesis-promoting topical treatment for diabetic wounds, which promotes angiogenesis by mimicking a hypoxic environment via inhibition of prolyl hydroxylase resulting in elevation or maintenance of hypoxia inducible factor (HIF), was investigated utilizing a custom-built multimodal microscopy system equipped with phase-variance optical coherence tomography (PV-OCT) and fluorescence lifetime imaging microscopy (FLIM). PV-OCT was used to track ...

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    18. Flexible wide-field optical micro-angiography based on Fourier-domain multiplexed dual-beam swept source optical coherence tomography

      Flexible wide-field optical micro-angiography based on Fourier-domain multiplexed dual-beam swept source optical coherence tomography

      Wide-field optical coherence tomography angiography (OCTA) is gaining interest in clinical imaging applications. In this pursuit, it is challenging to maintain the imaging resolution and sensitivity throughout the wide field of view (FoV). Here, we propose a novel method/system of dual-beam arrangement and Fourier domain multiplexing to achieve wide field OCTA when imaging the uneven surface samples. The proposed system provides two separate FoVs, with flexibility that the imaging area, focus of the imaging beam and imaging depth range can be individually adjusted for each FoV, leading to either 1) increased system imaging FoV or 2) capability of targeting ...

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    19. Real-time optical coherence tomography coregistration with angiography in percutaneous coronary intervention–impact on physician decision-making: The OPTICO-integration study

      Real-time optical coherence tomography coregistration with angiography in percutaneous coronary intervention–impact on physician decision-making: The OPTICO-integration study

      Aims Intracoronary optical coherence tomography (OCT) imaging allows for high-resolution characterization of coronary lesions. Difficulties in matching cross-sectional OCT-images with angiographic lesion localization may limit optimal clinical utilization. We sought to prospectively assess the impact of a novel system of real-time OCT coregistration with angiography (ACR) on physician decision-making during percutaneous coronary interventions (PCI). Methods and Results Strategy for PCI (stent - length, - diameter, - strategy, landing zone) and PCI-optimization (stent-malappostion, -underexpansion, edge-dissections, geographical mismatch) was prospectively assessed in 50 patients with 58 coronary lesions after (I) angiography, (II) OCT imaging, and (III) ACR. Preprocedural OCT imaging altered stent-length (58.9%), diameter ...

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    20. Evaluation of retinal nerve fibre layer, ganglion cell layer and choroidal thickness with optical coherence tomography in migraine patients: a case-control study

      Evaluation of retinal nerve fibre layer, ganglion cell layer and choroidal thickness with optical coherence tomography in migraine patients: a case-control study

      Background Evaluation of retinal nerve fibre layer (RNFL), ganglion cell layer (GCL) and choroidal thickness (CT) with optical coherence tomography (OCT) in chronic migraine patients, to compare with healthy controls. Material and Method Ninety-four eyes of 47 chronic migraine patients (Group 1) and 68 eyes of 34 healthy individuals (Group 2) were included in this prospective case-control study. The right and left eyes were separately evaluated. Mean peripapillary RNFL thicknesses, mean GCL measured from superior and inferior quadrants, and mean CT were measured at three different regions (central, 500 μm nasal and temporal region of the fovea). Results There was ...

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