1. 1-24 of 785 1 2 3 4 ... 31 32 33 »
    1. Comparison of diagnostic performance in assessing the rewiring position into a jailed side branch between online 3D reconstruction systems version 1.1 and 1.2 derived from optical frequency domain imaging

      Comparison of diagnostic performance in assessing the rewiring position into a jailed side branch between online 3D reconstruction systems version 1.1 and 1.2 derived from optical frequency domain imaging

      The three-dimensional reconstruction of optical coherence tomography and optical frequency domain imaging (3D-OCT/OFDI) helps optimize bifurcation percutaneous coronary interventions (PCIs) with side branch (SB) dilatation by identifying the optimal rewiring position. 3D-OCT/OFDI’s diagnostic performance for assessing the rewiring position into a jailed SB is unknown. We retrospectively evaluated the diagnostic performances of a conventional (ver. 1.1) and a new (ver. 1.2) online 3D-OFDI reconstruction system based on an offline 3D reconstruction system’s performance. We analyzed 45 patients’ 52 OFDI pullbacks with main vessel stenting followed by rewiring into a jailed SB for coronary bifurcation ...

      Read Full Article
      Mentions: Takayuki Okamura
    2. Corneal sublayer thickness in patients with pseudoexfoliation syndrome evaluated by anterior segment optical coherence tomography

      Corneal sublayer thickness in patients with pseudoexfoliation syndrome evaluated by anterior segment optical coherence tomography

      Purpose The aim of the study was to evaluate the thickness of each corneal sublayer in patients with pseudoexfoliation syndrome (PXS). Methods The study’s sample consisted of the 74 eyes of 74 patients with PXS (group 1) and the 80 eyes of 80 individuals without PXS (group 2). Each participant was performed anterior segment optical coherence tomography (AS-OCT) and Pentacam–Scheimpflug imaging. The thicknesses of corneal epithelium, Bowman’s layer, stroma, and Descemet membrane–endothelial complex were measured separately from the AS-OCT images, on the central, 2 mm superior and inferior of the cornea. Central corneal thickness (CCT), apical ...

      Read Full Article
    3. Extended focus optical coherence tomography with Fresnel lens

      Extended focus optical coherence tomography with Fresnel lens

      We report a Fresnel lens based spectral domain optical coherence tomography (SDOCT) setup to overcome the trade-off between lateral resolution and focusing depth which is one of the main problems for OCT system. We demonstrated the feasibility of the Fresnel lens based SDOCT system by measuring the lateral resolution at different depth positions and compared these results with that obtained by conventional SDOCT illuminated with a light source of a central wavelength of 840 nm and a bandwidth of 50 nm. These results indicated that the Fresnel lens based SDOCT can maintain a constant lateral resolution (~ 6.2 μm or ...

      Read Full Article
    4. Visual impairment in children with a brain tumor: a prospective nationwide multicenter study using standard visual testing and optical coherence tomography (CCISS study)

      Visual impairment in children with a brain tumor: a prospective nationwide multicenter study using standard visual testing and optical coherence tomography (CCISS study)

      Background Children with a brain tumor have a high risk of impaired vision. Up to now, visual acuity measurement, visual field testing and orthoptic testing are the most informative diagnostic investigations for the assessment of visual function. Evaluating vision in children can be challenging given the challenges in cooperation, concentration and age-dependent shifts in visual tests. Since visual loss due to a brain tumor can be progressive and irreversible, we must aim to detect visual impairment as early as possible. Several studies have shown that optical coherence tomography facilitates discovery of nerve fiber damage caused by optic nerve glioma. Consequently ...

      Read Full Article
    5. OCT Image-Guided Treatment of Scars (Book Chapter)

      OCT Image-Guided Treatment of Scars (Book Chapter)

      Improved scar rehabilitation is achieved with lasers by matching laser settings to heterogeneous thickness of fibrous pathology. Optical coherence tomography (OCT) provides accurate depth measurement and demonstrates vascularity in scar and healthy tissue noninvasively providing a clinical endpoint for optimally calculating dosimetry. Real-time imaging during treatment allows personalized treatment due to varying collagen densities in cicatricial tissues

      Read Full Article
    6. Optical Coherence Tomography for Imaging Dental Caries (Book Chapter)

      Optical Coherence Tomography for Imaging Dental Caries (Book Chapter)

      Optical Coherence tomography (OCT) is a noninvasive technique that can be used to measure reflectivity within dental hard tissues. Due to the strong reflection at the tooth surfaces, the contrast between sound and demineralized tissues can be enhanced by use of polarization. Polarized sensitive OCT (PS-OCT) can monitor demineralization and remineralization. Clinical studies have indicated that OCT was able to demonstrated penetration into DEJ more reliably that radiographs in questionable occlusal caries. In root caries, the system was able to discriminate sound dentin from demineralized dentin, assess cementum thickness and determine lesion severity by using shrinkage of dentin as a ...

      Read Full Article
    7. Changes in choroidal vascular parameters following pan-retinal photocoagulation using swept-source optical coherence tomography

      Changes in choroidal vascular parameters following pan-retinal photocoagulation using swept-source optical coherence tomography

      Background To assess the effect of pan-retinal photocoagulation (PRP) on choroidal vascular parameters in eyes with advanced diabetic retinopathy (DR). Methods Forty patients (65 eyes) with severe nonproliferative DR or proliferative DR who underwent PRP were included. Changes in choroidal vascular parameters were assessed at 3, 6, and 12 months after PRP by using swept-source optical coherence tomography (OCT) and OCT angiography and were compared with baseline values. Results Choroidal vascularity index (CVI) significantly decreased from 66.27% ± 1.55% at baseline to 65.85% ± 1.61%, 65.77% ± 1.29%, and 65.74% ± 1.60% at 3, 6, and ...

      Read Full Article
    8. Monitoring retinal changes with optical coherence tomography predicts neuronal loss in experimental autoimmune encephalomyelitis

      Monitoring retinal changes with optical coherence tomography predicts neuronal loss in experimental autoimmune encephalomyelitis

      Background Retinal optical coherence tomography (OCT) is a clinical and research tool in multiple sclerosis, where it has shown significant retinal nerve fiber (RNFL) and ganglion cell (RGC) layer thinning, while postmortem studies have reported RGC loss. Although retinal pathology in experimental autoimmune encephalomyelitis (EAE) has been described, comparative OCT studies among EAE models are scarce. Furthermore, the best practices for the implementation of OCT in the EAE lab, especially with afoveate animals like rodents, remain undefined. We aimed to describe the dynamics of retinal injury in different mouse EAE models and outline the optimal experimental conditions, scan protocols, and ...

      Read Full Article
      Mentions: Ari J. Green
    9. Neointimal characteristics comparison between biodegradable-polymer and durable-polymer drug-eluting stents: 3-month follow-up optical coherence tomography light property analysis from the RESTORE registry

      Neointimal characteristics comparison between biodegradable-polymer and durable-polymer drug-eluting stents: 3-month follow-up optical coherence tomography light property analysis from the RESTORE registry

      We aimed to quantitatively assess a possible difference of the neointimal quality between biodegradable polymer- (BP-) and durable polymer drug-eluting stents (DP-DESs). We conducted a single-center all-comer prospective cohort study: the RESTORE registry (UMIN000033009). All patients who received successful OCT examination at planned 3-month follow-up after DES implantation were analyzed. Study population was divided into 2 groups, BP-DES versus DP-DES groups. We evaluated standard OCT variables, coverage percent, and the quantitative light property values including light intensity, attenuation, and backscatter. We performed OCT analyses of 121 lesions in 98 patients (BP-DES 55 lesions in 51 patients vs. DP-DES 66 lesions ...

      Read Full Article
    10. Optical coherence tomography (OCT) features of cystoid spaces in choroideremia (CHM)

      Optical coherence tomography (OCT) features of cystoid spaces in choroideremia (CHM)

      Purpose To investigate the prevalence and features of cystoid spaces (CS) in patients with confirmed genetic diagnosis of choroideremia (CHM) using swept source optical coherence tomography (OCT). Methods We retrospectively reviewed CHM patients examined at the Regional Reference Center for Hereditary Retinal Degenerations at the Eye Clinic in Florence. We took into consideration genetically confirmed CHM patients with ophthalmological and swept source optical coherence tomography (OCT) examinations. The presence/absence and location of cystoid spaces in the retina of each eye were reported. Results A total of 42 eyes of 21 CHM patients were included in our series. The average ...

      Read Full Article
    11. Authors’ reply to: Using anterior segment optical coherence tomography to compare the smoothness of anterior iris surface between two eyes in unilateral Fuchs’ uveitis syndrome

      Authors’ reply to: Using anterior segment optical coherence tomography to compare the smoothness of anterior iris surface between two eyes in unilateral Fuchs’ uveitis syndrome

      We thank Zarei M et al. for the comments on our article [ 1 ]. Iris changes are well-known features of Fuchs’ uveitis syndrome (FUS). Diffuse iris atrophy without hypochromia is reported as 49% in a large longitudinal study [ 2 ]. However, the decision on diffuse atrophy existence in this study has been made by observation not based on quantitative analysis. The studies that conducted for analysis of iris thickness of FUS quantitatively have shown decreased iris thickness (IT) in the affected eye compared with the healthy fellow eye [ 3 , 4 ]. In our study, we could not have found a statistically significant difference ...

      Read Full Article
    12. Using anterior segment optical coherence tomography to compare the smoothness of anterior iris surface between two eyes in unilateral Fuchs’ uveitis syndrome

      Using anterior segment optical coherence tomography to compare the smoothness of anterior iris surface between two eyes in unilateral Fuchs’ uveitis syndrome

      Dear editor, We read with great interest the article by Ozer et al. [ 1 ] titled “In vivo analysis and comparison of anterior segment structures of both eyes in unilateral Fuchs’ uveitis syndrome”. Using the specular microscope and anterior segment optical coherence tomography (ASOCT), the authors compared corneal endothelial cell density (ECD), iris stromal thickness (IST), iris pigment epithelium optical density (IPE OD), and Schlemm’s canal (SC) measurements in patients having unilateral Fuchs’ uveitis syndrome (FUS). They concluded that, despite significant reduction in IPE OD in temporal side of iris in FUS eyes, the mean IST is not significantly different ...

      Read Full Article
    13. Impact of integrated multiple image averaging on OCT angiography image quality and quantitative parameters

      Impact of integrated multiple image averaging on OCT angiography image quality and quantitative parameters

      Purpose Multiple image averaging (MIA) is a new approach to improve OCT angiography (OCTA) imaging. The aim of this work was to analyze the impact of MIA on image quality and quantitative OCTA parameters. Methods Twenty eyes from 20 healthy volunteers (55.65 ± 14.8 years) were prospectively enrolled. Imaging was performed using two commercially available OCTA devices (Canon OCT HS-100, Optovue AngioVue) using a uniform imaging protocol. Each participant had two single scans of the macula (3 × 3mm, Canon and Optovue) as well as five continuous single scan imaging procedures (3 × 3mm each) using the Canon device. Three out ...

      Read Full Article
    14. Automatic fibroatheroma identification in intravascular optical coherence tomography volumes

      Automatic fibroatheroma identification in intravascular optical coherence tomography volumes

      Coronary heart disease is the most common type of heart disease that leads to heart attacks. The identification of vulnerable plaques, especially the thin-cap fibroatheroma (TCFA), is crucial to the diagnosis of coronary artery disease. Intravascular optical coherence tomography (IVOCT), an emerging imaging modality, has been proven to be useful for the identification of vulnerable plaques. In this work, we propose an approach to identify the volumes with fibroatheroma frames automatically. In the proposed method, we first detect the lumen using a graph-search based method from unfolded images. Then a region of interest starting from the lumen boundary is cropped ...

      Read Full Article
    15. Cardiovascular OCT Imaging (Textbook)

      Cardiovascular OCT Imaging (Textbook)

      This heavily revised second edition comprehensively reviews the use of optical coherence tomography (OCT) in cardiovascular practice. It provides detailed guidance on how to properly interpret OCT images and successfully utilise it in daily clinical practice Chapters cover the development and physics associated with OCT, relevant interpretation skills, OCT imaging artifacts, plaque erosion, bioabsorbable stent, the detection of vulnerable plaque, and the use of OCT imaging in unison with other modalities such as phase contrast imaging (PCI). Areas of potential future development are also covered Cardiovascular OCT Imaging enables interventional cardiologists and cardiologists to quickly become both familiar and develop ...

      Read Full Article
    16. Expert consensus statement for quantitative measurement and morphological assessment of optical coherence tomography

      Expert consensus statement for quantitative measurement and morphological assessment of optical coherence tomography

      In this document, the methods for the quantitative measurement and morphological assessment of optical coherence tomography (OCT)/optical frequency domain imaging images (OFDI) are briefly summarized. The focus is on the clinical application of OCT/OFDI to guide percutaneous coronary interventions.

      Read Full Article
    17. Region-Based Segmentation of Capillary Density in Optical Coherence Tomography Angiography

      Region-Based Segmentation of Capillary Density in Optical Coherence Tomography Angiography

      Microvascular changes are one of the early symptoms of retinal diseases. Recently developed optical coherence tomography angiography (OCTA) technology allows visualization and analysis of the retinal microvascular network in a non-invasive way. However, automated analysis of microvascular changes in OCTA is not a trivial task. Current approaches often attempt to directly segment the microvasculature. These approaches generally have problems in cases of poor image quality and limited visibility of the vasculature. Evaluating the quality of the results is also challenging because of the difficulty of manually tracing the microvasculature, especially in cases of low image quality or with images with ...

      Read Full Article
    18. Structure-Aware Noise Reduction Generative Adversarial Network for Optical Coherence Tomography Image

      Structure-Aware Noise Reduction Generative Adversarial Network for Optical Coherence Tomography Image

      Optical coherence tomography (OCT) is a common imaging examination in ophthalmology, which can visualize cross-sectional retinal structures for diagnosis. However, image quality still suffers from speckle noise and other motion artifacts. An effective OCT denoising method is needed to ensure the image is interpreted correctly. However, lack of paired clean image restricts its development. Here, we propose an end-to-end structure-aware noise reduction generative adversarial network (SNR-GAN), trained with un-paired OCT images. The network is designed to translate images between noisy domain and clean domain. Besides adversarial and cycle consistence loss, structure-aware loss based on structural similarity index (SSIM) is added ...

      Read Full Article
    19. 3D-CNN for Glaucoma Detection Using Optical Coherence Tomography

      3D-CNN for Glaucoma Detection Using Optical Coherence Tomography

      The large size of raw 3D optical coherence tomography (OCT) volumes poses challenges for deep learning methods as it cannot be accommodated on a single GPU in its original resolution. The direct analysis of these volumes however, provides advantages such as circumventing the need for the segmentation of retinal structures. Previously, a deep learning (DL) approach was proposed for the detection of glaucoma directly from 3D OCT volumes, where the volumes were significantly downsampled first. In this paper, we propose an end-to-end DL model for the detection of glaucoma that doubles the number of input voxels of the previously proposed ...

      Read Full Article
    20. U-Net with Spatial Pyramid Pooling for Drusen Segmentation in Optical Coherence Tomography

      U-Net with Spatial Pyramid Pooling for Drusen Segmentation in Optical Coherence Tomography

      The presence of drusen is the main hallmark of early/intermediate age-related macular degeneration (AMD). Therefore, automated drusen segmentation is an important step in image-guided management of AMD. There are two common approaches to drusen segmentation. In the first, the drusen are segmented directly as a binary classification task. In the second approach, the surrounding retinal layers (outer boundary retinal pigment epithelium (OBRPE) and Bruch’s membrane (BM)) are segmented and the remaining space between these two layers is extracted as drusen. In this work, we extend the standard U-Net architecture with spatial pyramid pooling components to introduce global feature ...

      Read Full Article
    21. Acoustic Radiation Force Optical Coherence Elastography

      Acoustic Radiation Force Optical Coherence Elastography

      Mechanical properties, such as the elasticity and viscosity, are often major indicators of diseases. Over the years, tissue mechanical properties have been demonstrated to be an early indicator for cardiovascular disease. Mechanical imaging technologies have been quickly evolving with a goal to effectively diagnose coronary artery disease and atherosclerosis in their early stages. By combining the advantages of acoustic and optical properties, acoustic radiation force optical coherence elastography (ARF-OCE) has become an imaging tool with a high potential for translation into clinics. In this chapter, we review the principles of OCE and describe the development of ARF-OCE systems for imaging ...

      Read Full Article
    22. Optical coherence tomography of onychomycosis: proposed terminology and a suggestion of practical usage

      Optical coherence tomography of onychomycosis: proposed terminology and a suggestion of practical usage

      Onychomycosis is the most common cause of nail changes accounting for about half of all nail diseases. It is important to diagnose the fungal pathogen to prescribe adequate treatment, but as genus- and species-specific diagnostic tests can be time consuming and expensive, it is crucial to obtain representative tissue during nail scrapings. Optical coherence tomography (OCT) is a non-invasive imaging tool enabling real-time imaging of skin and tissue. Pilot studies using OCT have described morphological characteristics of onychomycosis, though diagnostic criteria of onychomycosis and other nail diseases are lacking. The aim of this study is to investigate the applicability of ...

      Read Full Article
    23. 3D Fingerprint Gender Classification Using Deep Learning

      3D Fingerprint Gender Classification Using Deep Learning

      Optical Coherence Tomography (OCT) is a high resolution imaging technology, which provides a 3D representation of the fingertip skin. This paper for the first time investigates gender classification using those 3D fingerprints. Different with current fingerprint gender classification methods, the raw multiple longitudinal( X - Z ) fingertip images of one finger can be applied instead of studying features extracted from fingerprints, and the model can be trained effectively when the training data set is relatively small. Experimental results show that the best accuracy of 80.7% is achieved by classifying left fore finger on a small database with 59 persons. Meanwhile ...

      Read Full Article
    24. Spectral domain optical coherence tomography based imaging biomarkers for diabetic retinopathy

      Spectral domain optical coherence tomography based imaging biomarkers for diabetic retinopathy

      To evaluate the role of central subfield thickness (CST), cube average thickness (CAT), and cube volume (CV) as imaging biomarkers for severity of diabetic retinopathy within the ETDRS-based grades of retinopathy using spectral domain optical coherence tomography (SD-OCT). This study aims to evaluate the role of macular CST, CAT, and CV on SD-OCT as imaging biomarkers for severity of DR. One hundred ninety-four consecutive cases of type 2 diabetes mellitus were divided according to ETDRS classification: diabetes mellitus without retinopathy (No DR; n  = 65), nonproliferative diabetic retinopathy (NPDR; n  = 66), and proliferative diabetic retinopathy (PDR; n  = 63). Sixty-three healthy controls ...

      Read Full Article
    1-24 of 785 1 2 3 4 ... 31 32 33 »
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks