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    1. Role of Intravascular Imaging in Primary PCI (Book Chapter)

      Role of Intravascular Imaging in Primary PCI (Book Chapter)

      Primary percutaneous coronary intervention (PPCI) is always targeted on the angiographically identified culprit lesion. However, the actual culprit lesion may not compromise the lumen and can be located proximally or distally to the angiographic target lesion. As a result, the risk of incomplete lesion coverage can be high when the PPCI is guided solely by angiography. Furthermore, stent implantation must be optimized, as incomplete apposition and/or edge dissection may result in in-stent restenosis or acute thrombotic events. Thus, invasive coronary imaging using intravascular ultrasound or optical coherence tomography can be useful to guide the PPCI procedure by locating the ...

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    2. Changes in conjunctival–scleral thickness after strabismus surgery measured with anterior segment optical coherence tomography

      Changes in conjunctival–scleral thickness after strabismus surgery measured with anterior segment optical coherence tomography

      Purpose To evaluate changes in conjunctival–scleral thickness following strabismus surgery with anterior segment optical coherence tomography (AS-OCT). Study Design Prospective, observational, consecutive case series. Methods Distances between the conjunctival epithelium and inner scleral wall were measured with AS-OCT before and 3–5 months after strabismus surgery. The measurements were performed at 1.5 mm (limbus), 7.0 mm (insertion), and 8.0 mm (tendon) posterior to the scleral spur on the lateral rectus muscle (LR); and 1.5 mm (limbus), 4.0 mm (insertion), and 5.5 mm (tendon) posterior to the scleral spur on the medial rectus muscle ...

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    3. In-Vitro Detection of Small Isolated Cartilage Defects: Intravascular Ultrasound Vs. Optical Coherence Tomography

      In-Vitro Detection of Small Isolated Cartilage Defects: Intravascular Ultrasound Vs. Optical Coherence Tomography

      This experimental work focused on the sensor selection for the development of a needle-like instrument to treat small isolated cartilage defects with hydrogels. The aim was to identify the most accurate and sensitive imaging method to determine the location and size of defects compared to a gold standard (µCT). Only intravascular ultrasound imaging (IVUS) vs. optical coherent tomography (OCT) were looked at, as they fulfilled the criteria for integration in the needle design. An in-vitro study was conducted on six human cadaveric tali that were dissected and submerged in saline. To simulate the natural appearance of cartilage defects, three types ...

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    4. The clinical usefulness of optical coherence tomography during cancer interventions

      The clinical usefulness of optical coherence tomography during cancer interventions

      Introduction Tumor detection and visualization plays a key role in the clinical workflow of a patient with suspected cancer, both in the diagnosis and treatment. Several optical imaging techniques have been evaluated for guidance during oncological interventions. Optical coherence tomography (OCT) is a technique which has been widely evaluated during the past decades. This review aims to determine the clinical usefulness of OCT during cancer interventions focussing on qualitative features, quantitative features and the diagnostic value of OCT. Methods A systematic literature search was performed for articles published before May 2018 using OCT in the field of surgical oncology. Based ...

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    5. Automatic Detection and Characterization of Biomarkers in OCT Images

      Automatic Detection and Characterization of Biomarkers in OCT Images

      Optical Coherence Tomography (OCT) is one of the most advanced, non-invasive method of eye examination. Age-related macular degeneration (AMD) is one of the most frequent reasons of acquired blindness. Our aim is to develop automatic methods that can accurately identify and characterize biomarkers in OCT images, related to AMD. We present methods for quantizing hyperreflective foci (HRF) with deep learning. We also describe an algorithm for determining pigmentepithelial detachment (PED) and localizing outer retinal tubulation (ORT) that appears between the layers of the retina.

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    6. Innovative Endoscopies to Be Clinically Used in the Near Future

      Innovative Endoscopies to Be Clinically Used in the Near Future

      In contrast to traditional single-lens endoscopies, recently introduced full-spectrum endoscopy (FUSE) scopes include multiple lenses providing a much wider field of view. In many studies, FUSE was shown to be feasible, effective, and safe, and FUSE colonoscopy yielded higher polyp (PDR), adenoma (ADR), and diverticular (DDR) detection rates than did traditional colonoscopy, without therapeutic failure or complications. Moreover, using FUSE gastroscopy, the prevalence of duodenal peri-ampullary diverticula (DPAD) in the general population could be analyzed without using ERCP. In the future, the next generation of modified FUSE system is expected to be useful in direct peroral cholangioscopy and in simultaneous ...

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    7. Clinical efficacy of aspirin with identification of intimal morphology by optical coherence tomography in preventing event recurrence in patients with vasospasm-induced acute coronary syndrome

      Clinical efficacy of aspirin with identification of intimal morphology by optical coherence tomography in preventing event recurrence in patients with vasospasm-induced acute coronary syndrome

      Using optical coherence tomography (OCT), we found that there were morphological differences in the coronary intima between patients with vasospasm-induced acute coronary syndrome (VACS) and those with stable variant angina. We investigated whether aspirin use would protect against chest pain recurrence in patients with VACS. A retrospective cohort study was performed. Patients with ST-segment elevation who were confirmed to have VACS by a provocation test were included. OCT was performed at the index event and when chest pain recurred to assess intimal morphology. Chest pain recurrence was defined as the first revisit to the emergency room with angina. Propensity score ...

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    8. Optical coherence tomography angiography in retinal vein occlusions

      Optical coherence tomography angiography in retinal vein occlusions

      Purpose To examine the vascular density in different retinal layers and in the choriocapillaris in eyes with retinal vein occlusions (RVO). Methods Applying optical coherence tomography angiography (OCTA), we examined patients with unilateral RVOs and normal individuals of a control group. Results The study group included 48 patients with unilateral RVO and the control group 17 normal individuals. Eyes affected by RVO as compared to the contralateral unaffected eyes (all P  < 0.001), and the contralateral unaffected eyes as compared to the eyes of the control group ( P  < 0.05), showed a lower vessel density in the superficial and deep ...

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      Mentions: Jost B. Jonas
    9. Optical coherence tomography guidance in percutaneous coronary intervention: a meta-analysis of randomized controlled trials

      Optical coherence tomography guidance in percutaneous coronary intervention: a meta-analysis of randomized controlled trials

      The benefit of optical coherence tomography (OCT) guidance in percutaneous coronary intervention (PCI) is unclear. We aimed to assess the incremental value of adding OCT to coronary angiography in PCI by meta-analytic technique. We searched PubMed, EMBASE, Cochrane, Scopus and relevant references for randomized studies (inception through January 5, 2018 without language restrictions) and performed meta-analysis using random effects model. Major adverse cardiac events (MACE), all-cause mortality, myocardial infarction, target vessel revascularization, stent thrombosis, fluoroscopic time, contrast volume, and procedural side effects were the measured outcomes. Five randomized studies with a total population of 931 were analyzed. There was no ...

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    10. Pigmented Lesions: Biopsy Methods and Emerging Non-invasive Imaging Techniques (Book Chapter)

      Pigmented Lesions: Biopsy Methods and Emerging Non-invasive Imaging Techniques (Book Chapter)

      Melanoma incidence has been increasing in the US population, with early detection and treatment leading to decreased morbidity and mortality. The first steps in diagnosis are clinical examination and skin biopsy. Various methods of skin biopsy exist and the appropriate choice can be challenging. In this chapter, we review various biopsy techniques including excisional, scoop (saucerization), incisional or punch, shave, biopsy of special sites, and emerging noninvasive imaging techniques for pigmented lesions including reflectance confocal microscopy, optical coherence tomography, digital multispectral dermoscopy, and tape stripping mRNA.

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    11. Sub-4-micron full-field optical coherence tomography on a budget

      Sub-4-micron full-field optical coherence tomography on a budget

      We evaluate the construction and performance of an ultra-low-cost full-field optical coherence tomography (FF-OCT) instrument, also known as an optical coherence microscope. Although the cost of construction of the instrument from off-the-shelf parts is at least ten times lower than those of commercial products, sub-4-micron axial and lateral resolutions are obtained, albeit at the cost of higher acquisition times. Standard test samples are imaged and the performance of the instrument is evaluated. The device is found to be useful in measuring length, dispersion and group refractive index as well. Suggestions for bettering performance are discussed.

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    12. Choroidal thickness changes in non-treated eyes of patients with diabetes: swept-source optical coherence tomography study

      Choroidal thickness changes in non-treated eyes of patients with diabetes: swept-source optical coherence tomography study

      Aims To measure choroidal thickness (CT) in diabetic eyes and its correlation with metabolic status and the severity of diabetic retinopathy (DR). Materials and methods Prospective cross-sectional study using swept-source optical coherence tomography. CT maps of 96 treatment naïve eyes of 48 patients with diabetes were compared to 46 eyes of 23 healthy controls. CT changes and their relation to diabetes, age, gender, disease duration, hypertension (HT), hemoglobin A1c level, type and severity of DR were evaluated. Results A significantly thinner choroid was measured in patients with diabetes compared to controls ( p  < 0.009). In the diabetic group age ...

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    13. A review in enormity of OCT and its enduring understanding of vulnerable plaque in coronary bifurcation lesion

      A review in enormity of OCT and its enduring understanding of vulnerable plaque in coronary bifurcation lesion

      Optical coherence tomography (OCT) has emerged as one of the most promising tools to assist the optimization of percutaneous coronary intervention (PCI). Its ability to provide unique information on the plaque at high risk for rupture, plaque composition, the thickness of the fibrous cap, the presence of macrophage and thrombi has not only assisted simple PCI but also in many complex bifurcation lesions PCI. OCT has helped to provide valuable anatomic information to optimize stent implantation and adapt PCI strategy in individual patients. This review article summarizes the current role of OCT as an imaging technology and prediction of vulnerable ...

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    14. Development of an efficient algorithm for the detection of macular edema from optical coherence tomography images

      Development of an efficient algorithm for the detection of macular edema from optical coherence tomography images

      Purpose Detection of eye diseases and their treatment is a key to reduce blindness, which impacts human daily needs like driving, reading, writing, etc. Several methods based on image processing have been used to monitor the presence of macular diseases. Optical coherence tomography (OCT) imaging is the most efficient technique used to observe eye diseases. This paper proposes an efficient algorithm to automatically classify normal as well as disease-affected (macular edema) retinal OCT images by using segmentation of Inner Limiting Membrane and the Choroid Layer. Methods In the proposed method, preprocessing of the input image is done to improve the ...

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      Mentions: Duke University
    15. Cross-Polarization Optical Coherence Tomography with Active Maintenance of the Circular Polarization of a Sounding Wave in a Common Path System

      Cross-Polarization Optical Coherence Tomography with Active Maintenance of the Circular Polarization of a Sounding Wave in a Common Path System

      We consider a cross-polarization optical coherence tomography system with a common path for the sounding and reference waves and active maintenance of the circular polarization of a sounding wave. The system is based on the formation of birefringent characteristics of the total optical path, which are equivalent to a quarter-wave plate with a 45° orientation of its optical axes with respect to the linearly polarized reference wave. Conditions under which any light-polarization state can be obtained using a two-element phase controller are obtained. The dependence of the local cross-scattering coefficient of light in a model medium and biological tissue on ...

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    16. One-year optical coherence tomography findings in patients with late and very-late stent thrombosis treated with intravascular imaging guided percutaneous coronary intervention

      One-year optical coherence tomography findings in patients with late and very-late stent thrombosis treated with intravascular imaging guided percutaneous coronary intervention

      Patients with late/very-late stent thrombosis (ST) are at high risk of recurrent-ST. The mechanisms of recurrent-ST are largely unknown. The objective is to describe the 1-year optical coherence tomography (OCT) findings of patients suffering from late/very-late ST treated with intravascular imaging guided percutaneous coronary intervention (PCI). All consecutive patients with late/very-late ST undergoing intravascular imaging guided PCI were screened to undergo coronary angiography and OCT examination at 1 year. Patients were classified according to the observation of stent malapposition as most contributing cause of the ST. Thirty-four patients were included. Stent malapposition was observed in 17 (50 ...

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    17. Differences between first-generation and second-generation drug-eluting stent regarding in-stent neoatherosclerosis characteristics: an optical coherence tomography analysis

      Differences between first-generation and second-generation drug-eluting stent regarding in-stent neoatherosclerosis characteristics: an optical coherence tomography analysis

      We compared first-generation and second-generation drug-eluting stent (DES) with respect to neoatherosclerosis using optical coherence tomography or optical frequency domain imaging. In-stent restenoses in 102 first-generation and 114 second-generation DES were retrospectively assessed. Neoatherosclerosis, which was defined as the presence of lipid-laden neointima or calcification inside a stent, was observed in 33 (27.2%) and 31 (32.4%) lesions in the first-generation and second-generation DES respectively. In the first-generation DES group, the lipid length was significantly longer (5.5 ± 3.8 vs. 3.1 ± 2.1 mm, P  = 0.0007), the lipid arc was significantly larger (324 ± 70° vs. 250 ...

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    18. Optical coherence tomography in STEMI with bioresorbable scaffold: possible cause of coronary flow impairment? A sub-study from the Prague 19 trial

      Optical coherence tomography in STEMI with bioresorbable scaffold: possible cause of coronary flow impairment? A sub-study from the Prague 19 trial

      This study assessed the Optical Coherence Tomography (OCT) impact on the coronary flow in ST-elevation myocardial infarction (STEMI) after bioresorbable scaffold implantation. Only few data about OCT use in STEMI are available and coronary flow before and after OCT is not well studied yet. 54 patients with OCT performed at the end of procedure from the Prague 19 trial were selected and coronary flow was evaluated as TIMI frame count (TFC) before and just after OCT. Significant increase in TIMI frame count after OCT [from 9.5 (6.75–12.25) to 11.5 (8–15.25) frames; p = 0 ...

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    19. The Effect of Glatiramer Acetate on Retinal Nerve Fiber Layer Thickness in Patients with Relapsing–Remitting Multiple Sclerosis: A Longitudinal Optical Coherence Tomography Study

      The Effect of Glatiramer Acetate on Retinal Nerve Fiber Layer Thickness in Patients with Relapsing–Remitting Multiple Sclerosis: A Longitudinal Optical Coherence Tomography Study

      Background Optical coherence tomography (OCT) is a technique that allows for the assessment of retinal nerve fiber layer thickness (RNFLT) and total macular volume (TMV), which reflect neuroaxonal integrity within the retina. As such it has been used in multiple sclerosis (MS) to study neurodegeneration. Glatiramer acetate (GA) is a widely used treatment for MS, which is suggested to have a possible neuroprotective role. Objective The aim of this study was to assess RFNLT and TMV changes in relapsing–remitting MS (RRMS) patients who started treatment with GA and were followed for a 24-month period. Methods A cohort of 60 ...

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    20. Optical Coherence Tomography for Brain Imaging (Book Chapter)

      Optical Coherence Tomography for Brain Imaging (Book Chapter)

      Optical coherence tomography (OCT) is an imaging technique based on the detection of light back-reflected or backscattered by tissue. Based on the principles of low-coherence interferometry, OCT provides rapid volumetric imaging with micrometer-scale resolution. OCT has been massively successful in ophthalmology where it became a routine tool for retinal diagnostics. In recent years, however, OCT has also been applied to other fields including—amongst others—cardiovascular imaging, endoscopy of the gastrointestinal tract, and neuroimaging. In the brain and other neural tissues, OCT provides contrast for tissue microstructures and enables noninvasive in vivo and in vitro imaging with high resolution. Novel ...

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      Mentions: Bernhard Baumann
    21. Investigation of retinal nerve fiber layer thickness and ganglion cell layer-inner plexiform layer thickness in patients with optic pathway gliomas

      Investigation of retinal nerve fiber layer thickness and ganglion cell layer-inner plexiform layer thickness in patients with optic pathway gliomas

      Purpose This study aimed to compare the optical coherence tomography (OCT) findings of optic pathway glioma (OPG) patients (sporadic or secondary to neurofibromatosis type 1, NF1) with NF1 without OPG patients and healthy controls. Methods This was a prospective, case-control study in which 27 patients (13 with OPGs and 14 with NF1 without OPGs) and 13 control subjects were included. The retinal nerve fiber layer (RNFL) thickness, macular thickness, and ganglion cell layer-inner plexiform layer (GCL-IPL) thickness findings measured using OCT and the results were compared between the groups. Results The macular thickness was significantly lower in the OPG group ...

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    22. Equidistant Recording of the Spectral Components in Ultra-Wideband Spectral-Domain Optical Coherence Tomography

      Equidistant Recording of the Spectral Components in Ultra-Wideband Spectral-Domain Optical Coherence Tomography

      We develop an effective method for reducing nonequidistance when recording the spectral components of an interference signal in ultra-wideband spectral-domain optical coherence tomography. For this purpose, a corrector consisting of two identical prisms is used in a diffraction-grating spectrometer. The corrector rotation with respect to the diffraction-grating plane and a variation in the angle between the corrector elements allow one to adjust the equidistant spatial distribution of the spectral components in the photoreceiver array. It is shown experimentally that the developed method substitutes digital correction and leads to a significant reduction of the computational load in the optical coherence tomography ...

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