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    1. Early microvascular retinal changes in optical coherence tomography angiography in patients with type 1 diabetes mellitus

      Early microvascular retinal changes in optical coherence tomography angiography in patients with type 1 diabetes mellitus

      Purpose Diabetic retinopathy (DR) can lead to significant vision loss and blindness and has a particularly high prevalence in patients with type 1 diabetes (DM1). In this study, we investigate quantitative differences in optical coherence tomography angiography (OCTA) data between DM1 patients with no or mild signs of retinopathy and non-diabetic subjects. Methods Optical coherence tomography angiography (OCTA) imaging was performed on DM1 patients with no or mild nonproliferative diabetic retinopathy and healthy, age-matched controls. Parafoveal vessel density and foveal avascular zone (FAZ) area in the deep capillary plexus (DCP) and superficial capillary plexus (SCP) were calculated with automated quantification ...

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    2. Non-invasive skin imaging for the diagnosis of myiasis

      Non-invasive skin imaging for the diagnosis of myiasis

      A 52-year-old man presented with a painful ulceration of the scalp (Fig. 1a). He had returned from Guyana the previous week. Dermoscopic examination (FotoFinder Systems GmbH, Bad Birnbach, Germany) showed an intermittent dynamic aspect changing from a sanguineous roundish ulcer (Fig. 1b) to a peculiar roundish structure characterized by a yellowish peripheral ring and a central brownish part (Fig. 1c). High-definition optical coherence tomography (HD-OCT; Skintell ® ; Agfa Gevaert, Antverpen, Belgium) showed a skin cavity (Fig. 2a). Reflectance confocal microscopy (RCM; Vivascope 3000 ® , Caliber, New York, USA, distributed in Europe by MAVIG GmbH, München, Germany) showed the roundish structure observed ...

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      Mentions: AGFA Healthcare
    3. Optical coherence tomography imaging of bullous diseases

      Optical coherence tomography imaging of bullous diseases

      Background  Optical coherence tomography (OCT) is a non-invasive optical imaging technique with a micrometer resolution that may potentially offer real-time bedside imaging of sufficient detail to allow for morphological discrimination between different types of bullae. Objective  To explore the potential of OCT in bullous skin disorders by looking at a set of patients with skin blisters of known origin and study the OCT images for possible hallmarks of the blistering level. Materials and methods  OCT provides cross-sectional, tomographic images of the skin. A consecutive series of patients were recruited and their lesions imaged by OCT: 3 patients with bullous pemphigoid ...

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    4. Optical coherence tomography angiography of macular telangiectasia type 1: Comparison with mild diabetic macular edema

      Optical coherence tomography angiography of macular telangiectasia type 1: Comparison with mild diabetic macular edema

      Objective The present study aimed to investigate the characteristics of macular telangiectasia type 1 (Mac tel type 1) using spectral-domain optical coherence tomography angiography (OCTA) and compare them with the characteristics of mild diabetic macular edema (DME), to provide a new objective method for quick clinical diagnosis and treatment. Methods A retrospective comparative analysis of 9 Mac tel type 1, 15 DME, and 15 normal eyes was performed using fluorescein angiography, spectral-domain optical coherence tomography, and OCTA. The morphological changes, retinal vessel density, and nonperfused areas were evaluated using split-spectrum amplitude-decorrelation angiography algorithm. Results OCTA revealed obvious saccular capillary telangiectasia ...

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    5. Coronary artery aneurysm after implantation of a bioresorbable vascular scaffold: Case report and literature review

      Coronary artery aneurysm after implantation of a bioresorbable vascular scaffold: Case report and literature review

      A 55-year-old man underwent successful percutaneous coronary intervention for the middle left circumflex artery with a 3.5 × 28-mm bioresorbable vascular scaffold (BVS). At 18 months, follow-up coronary angiography showed ectatic change with aneurysm formation over the BVS. Optical coherence tomography revealed absence of strut continuity at the aneurysm site, in the middle of the BVS. A literature review identified nine patients with intrascaffold aneurysm, including the present patient, which developed 6–32 months after BVS implantation. Of these nine patients, four underwent percutaneous coronary intervention for chronic total occlusion. The pathogenesis of coronary artery aneurysm is multifactorial. Most patients ...

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    6. Intraluminal bioresorbable vascular scaffold dismantling with aneurysm formation leading to very late thrombosis

      Intraluminal bioresorbable vascular scaffold dismantling with aneurysm formation leading to very late thrombosis

      Coronary artery aneurysm formation has been described in patients after the placement of first-generation drug-eluting stents (DES), but is less common with newer generation metallic stents. In contrast, coronary artery aneurysm formation may be more common with the use of bioresorbable vascular scaffolds (BVS) due to the frequent formation of evaginations in the arterial wall seen with BVS. In this article, we describe a unique case of BVS dismantling and thrombus formation leading to an acute coronary syndrome thirty-two months after initial BVS placement. We also discuss existing literature and the pathophysiology of BVS degradation, in addition to the utility ...

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      Mentions: Gregg W. Stone
    7. Classification of mechanisms of strut malapposition after angiographically optimized stent implantation: An optical coherence tomography study

      Classification of mechanisms of strut malapposition after angiographically optimized stent implantation: An optical coherence tomography study

      Aims To elucidate causes and extent of strut malapposition in angiographically optimized stenting. Methods and Results Using a new classification system for strut malapposition, the mechanisms of stent strut malapposition were classified as localized lumen enlargement, vessel asymmetry, stent undersizing, strut underexpansion and stent deployment issue. Stent implantations ( n  = 110) in 100 consecutive patients undergoing optical coherence tomography (OCT) after the operator considered the stent as optimally deployed angiographically were reviewed to determine if strut apposition was complete. 127,894 stent struts in 110 stents were analyzed. There were 6,644 struts malapposed (5.2% ±7.3%), with strut malapposition ...

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    8. Reproducibility and repeatability of optical coherence tomography imaging of the optic nerve head in normal beagle eyes

      Reproducibility and repeatability of optical coherence tomography imaging of the optic nerve head in normal beagle eyes

      Objective To assess the reproducibility and repeatability of an optical coherence tomography (OCT) device for imaging the optic nerve region of normal canines. Animals studied Twelve clinically healthy beagles. Procedures All animals were anesthetized, and an OCT device was used to image the optic disk region. Total disk area and retinal nerve fiber layer (NFL) thickness in eight segments were obtained from each image. Images were collected by two operators in succession and each operator took five scans, repositioning the device between measurements. B-scan segmentations and disk outlines were subsequently redrawn to obtain manual measurements, allowing for comparisons between automated ...

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    9. Alterations of the outer retina in non-arteritic anterior ischemic optic neuropathy detected using spectral-domain optical coherence tomography

      Alterations of the outer retina in non-arteritic anterior ischemic optic neuropathy detected using spectral-domain optical coherence tomography

      Background Changes in peripapillary and macular retinal layer thickness in non-arteritic anterior ischemic optic neuropathy (NAION) measured using spectral-domain optical coherence tomography may reflect a characteristic disease pattern. Advanced software enables retinal layer segmentation. In this study, we compared retinal layer thicknesses in acute and chronic NAION. Design A single-center cross-sectional analysis in a university clinic. Participants 14 eyes with acute (<7 days) and 13 eyes with chronic NAION and 20 age-matched healthy eyes. Methods Macular volume and 12° peripapillary ring OCT scans (Spectralis®, Heidelberg Engineering). Main Outcome Measures The peripapillary thicknesses of the following layers were determined by manual ...

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    10. Differential standard deviation of log-scale intensity based optical coherence tomography angiography

      Differential standard deviation of log-scale intensity based optical coherence tomography angiography

      In this paper, a differential standard deviation of log-scale intensity (DSDLI) based optical coherence tomography angiography (OCTA) is presented for calculating microvascular images of human skin. The DSDLI algorithm calculates the variance in difference images of two consecutive log-scale intensity based structural images from the same position along depth direction to contrast blood flow. The en face microvascular images were then generated by calculating the standard deviation of the differential log-scale intensities within the specific depth range, resulting in an improvement in spatial resolution and SNR in microvascular images compared to speckle variance OCT and power intensity differential method. The ...

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    11. Identification and clinical role of choroidal neovascularization characteristics based on optical coherence tomography angiography

      Identification and clinical role of choroidal neovascularization characteristics based on optical coherence tomography angiography

      Purpose To suggest a novel classification of neovascular age-related macular degeneration (AMD) based on optical coherence tomography angiography (OCTA) and to correlate morphological characteristics based on optical coherence tomography (OCT)/OCTA with clinical criteria of disease activity. Methods A total of 88 eyes with neovascular AMD (14 treatment-naïve, 74 eyes following anti-vascular endothelial growth factor treatment (VEGF)) were examined using the AngioVue OCTA system (Optovue, Inc., Fremont, CA, USA) and evaluated based on vascular morphology. Choroidal neovascularization (CNV)-vessel morphology based on OCTA and associations with retinal layers were described and correlated with clinical markers of disease activity. Results ...

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    12. Automatic identification of parathyroid in optical coherence tomography images

      Automatic identification of parathyroid in optical coherence tomography images

      Background and Objective The identification and preservation of parathyroid is a major problem in thyroid surgery. In order to solve this problem, optical coherence tomography was involved as a real-time, non-invasive high-resolution imaging technique. This study demonstrated an effective and fast method to distinguish parathyroid tissue from thyroid, lymph node, and adipose tissue in their ex vivo optical coherence tomography (OCT) images automatically. Methods OCT images were obtained from parathyroid, thyroid, lymph node, and adipose tissue, respectively. A classification and an identification system based on texture features analysis and back propagation artificial neural network (BP-ANN) were established to classify the ...

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      Mentions: Yanmei Liang
    13. Intracoronary optical coherence tomography: Clinical and research applications and intravascular imaging software overview

      Intracoronary optical coherence tomography: Clinical and research applications and intravascular imaging software overview

      By providing valuable information about the coronary artery wall and lumen, intravascular imaging may aid in optimizing interventional procedure results and thereby could improve clinical outcomes following percutaneous coronary intervention (PCI). Intravascular optical coherence tomography (OCT) is a light-based technology with a tissue penetration of approximately 1 to 3 mm and provides near histological resolution. It has emerged as a technological breakthrough in intravascular imaging with multiple clinical and research applications. OCT provides detailed visualization of the vessel following PCI and provides accurate assessment of post-procedural stent performance including detection of edge dissection, stent struts apposition, tissue prolapse, and healing ...

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    14. Investigation of the variability of anterior chamber scan protocol with Cirrus high definition optical coherence tomography

      Investigation of the variability of anterior chamber scan protocol with Cirrus high definition optical coherence tomography

      Importance The evaluation of anterior chamber scan (ACS) of Cirrus optical coherence tomography (OCT) for routine clinical use Background To assess the variability of anterior chamber angle (ACA) measurements using the ACS Design Cross-sectional observational study Participants Forty subjects aged 40-80 years Methods One randomly selected eye from 40 subjects was imaged with Cirrus OCT (model 5000, Carl Zeiss Meditec, Dublin, CA) by two different operators (expert vs non-expert) with a 15-minute interval for inter- and intra-observer variability of image acquisition. For image grading, the angle opening distance (AOD750) and the trabecular iris space area (TISA750) of nasal and temporal ...

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    15. Use of optical coherence tomography for the diagnosis of preclinical lesions of circumscribed palmar hypokeratosis

      Use of optical coherence tomography for the diagnosis of preclinical lesions of circumscribed palmar hypokeratosis

      Circumscribed hypokeratosis of palms and soles is a rare dermatosis, usually affecting women. Diagnosis is mainly based on the clinical characteristics, including the clinical appearance and anatomical site of the skin lesions and on the demographic features of the affected patients, usually middle-aged to elderly women. Skin biopsy may be performed to confirm clinical diagnosis. Optical coherence tomography (OCT) is a technique that has been undergone substantial development in dermatology in recent years, and its use in clinical practice has been growing progressively. Several dermatological conditions have been studied with this tool, but to our knowledge, it has not been ...

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    16. A computer aided diagnostic system for detecting diabetic retinopathy in optical coherence tomography images

      A computer aided diagnostic system for detecting diabetic retinopathy in optical coherence tomography images

      urpose Detection (diagnosis) of diabetic retinopathy (DR) in optical coherence tomography (OCT) images for patients with type 2 diabetes, but almost clinically normal retina appearances. Methods The proposed computer-aided diagnostic (CAD) system detects the DR in three steps: (i) localizing and segmenting 12 distinct retinal layers on the OCT image; (ii) deriving features of the segmented layers, and (iii) learning most discriminative features and classifying each subject as normal or diabetic. To localise and segment the retinal layers, signals (intensities) of the OCT image are described with a joint Markov-Gibbs random field (MGRF) model of intensities and shape descriptors. Each ...

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    17. Impact of an optical coherence tomography guided approach in acute coronary syndromes: A propensity matched analysis from the international FORMIDABLE-CARDIOGROUP IV and USZ registry

      Impact of an optical coherence tomography guided approach in acute coronary syndromes: A propensity matched analysis from the international FORMIDABLE-CARDIOGROUP IV and USZ registry

      Aim. To determine the potential clinical impact of OCT (Optical Coherence Tomography) during primary percutaneous coronary intervention in patients presenting with ACS (Acute Coronary Syndrome). Methods and Results. FORMIDABLE is a multicentre retrospective registry enrolling all patients presenting with ACS and treated with an OCT-guided approach, while the USZ registry enrolled patients treated with a standard angiography guided approach. Multivariate adjustment was performed via a propensity score matching. The number stents useds was the primary outcome, while the incidence of MACE (a composite of death, myocardial infarction, target vessel revascularization, and stent thrombosis) was the secondary endpoint. A total of ...

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    18. Measurement of lacrimal punctum using spectralis domain anterior optical coherence tomography

      Measurement of lacrimal punctum using spectralis domain anterior optical coherence tomography

      Purpose Anterior segment optical coherence tomography (AS-OCT) was used to image the lacrimal punctum and establish normal punctal parameters including the tear volume inside the punctum. Methods This study included totally 67 eyes from 38 normal subjects. Punctal parameters and tear meniscus height (TMH) were measured using spectralis OCT anterior-segment scans. Outer punctal diameter (OPD), punctal depth, tear well diameter (TWD), tear well depth, punctal reserve (PR) and lower eyelid TMH were assessed. Authors defined a ‘tear well’ as a pool of standing tears in the punctum. Punctal reserve was defined as the difference between punctal depth and tear well ...

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    19. Comparative study of presurgical skin infiltration depth measurements of melanocytic lesions with OCT and high frequency ultrasound

      Comparative study of presurgical skin infiltration depth measurements of melanocytic lesions with OCT and high frequency ultrasound

      A reliable, fast, and non-invasive determination of melanoma thickness in vivo is highly desirable for clinical dermatology as it may facilitate the identification of surgical melanoma margins, determine if a sentinel node biopsy should be performed or not, and reduce the number of surgical interventions for patients. In this work, optical coherence tomography (OCT) and high frequency ultrasound (HFUS) are evaluated for quantitative in vivo preoperative assessment of the skin infiltration depth of melanocytic tissue. Both methods allow non-invasive imaging of skin at similar axial resolution. Comparison with the Breslow lesion thickness obtained from histopathology revealed that OCT is slightly ...

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    20. A useful way to develop effective in vivo skin optical clearing agents

      A useful way to develop effective in vivo skin optical clearing agents

      Skin optical clearing has shown tremendous potential in improving various optical imaging performances, but there is some certain blindness in screening out high-efficiency in vivo optical clearing methods. In this work, three optical clearing agents: sucrose (Suc), fructose (Fruc) and PEG-400 (PEG), and two chemical penetration enhancers: propylene glycol (PG) and thiazone (Thiaz) were used. PEG was firstly mixed with the two penetration enhancers, respectively, and then mixed with Fruc and Suc, respectively, to obtain six kinds of skin optical clearing agents (SOCAs). Optical coherence tomography angiography was applied to monitor SOCAs-induced changes in imaging performances, skin optical properties, refractive ...

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    21. Effect of different lubricant eye gels on tear film thickness as measured with ultrahigh-resolution optical coherence tomography

      Effect of different lubricant eye gels on tear film thickness as measured with ultrahigh-resolution optical coherence tomography

      Purpose To compare the effect of a single drop of different lubricant eye gels on tear film thickness (TFT) as measured with ultrahigh-resolution optical coherence tomography (UHR-OCT) in patients with mild-to-moderate dry eye disease (DED). Methods The study followed a randomized, single-masked, observer-blinded parallel group design. Patients received a single dose of either unpreserved trehalose 3% + hyaluronic acid 0.15% (TH), hyaluronic acid 0.2% (HA) or polyethylene glycol 0.4% + propylene glycol 0.3% (PP) eye drops. In total, 60 patients were included and TFT was measured using a custom-built UHR-OCT system. Results The mean TFT at baseline was ...

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    22. Modern trends in biophotonics for clinical diagnosis and therapy to solve unmet clinical needs

      Modern trends in biophotonics for clinical diagnosis and therapy to solve unmet clinical needs

      This contribution covers recent original research papers in the biophotonics field. The content is organized into main techniques such as multiphoton microscopy, Raman spectroscopy, infrared spectroscopy, optical coherence tomography and photoacoustic tomography, and their applications in the context of fluid, cell, tissue and skin diagnostics. Special attention is paid to vascular and blood flow diagnostics, photothermal and photodynamic therapy, tissue therapy, cell characterization, and biosensors for biomarker detection

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