1. Articles from jstage.jst.go.jp

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    1. Neoatherosclerosis ― Long-Term Assessment of Bioresorbable Vascular Scaffold ―

      Neoatherosclerosis ― Long-Term Assessment of Bioresorbable Vascular Scaffold ―

      Although metallic stents improved the safety and efficacy of percutaneous coronary intervention (PCI), even the latest generation of drug-eluting stents (DES) is still limited by several factors. The limitations of DES are mainly related to the permanent metallic caging in vessel, chronic inflammatory response to the polymer and adverse effects of antiproliferative drug on endothelial tissue, leading to impaired physiological vasomotor response and late stent-related adverse events such as stent thrombosis and neoatherosclerosis. Bioresorbable vascular scaffold (Absorb BVS; Abbott Vascular) was designed to overcome these drawbacks of DES by disappearing from the vessel wall. Absorb BVS, however, was withdrawn from ...

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    2. Intravascular Polarimetry for Tissue Characterization of Coronary Atherosclerosis

      Intravascular Polarimetry for Tissue Characterization of Coronary Atherosclerosis

      The microscopic tissue structure and organization influence the polarization of light. Intravascular polarimetry leverages this compelling intrinsic contrast mechanism by using polarization-sensitive optical frequency domain imaging to measure the polarization properties of the coronary arterial wall. Tissues rich in collagen and smooth muscle cells appear birefringent, while the presence of lipid causes depolarization, offering quantitative metrics related to the presence of important components of coronary atherosclerosis. Here, we review the basic principles, the interpretation of polarization signatures, and first clinical investigations of intravascular polarimetry and discuss how this extension of contemporary intravascular imaging may advance our knowledge and improve clinical ...

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    3. Efficacy and Reproducibility of Attenuation-Compensated Optical Coherence Tomography for Assessing External Elastic Membrane Border and Plaque Composition in Native and Stented Segments ― An In Vivo and Histology-Based Study ―

      Efficacy and Reproducibility of Attenuation-Compensated Optical Coherence Tomography for Assessing External Elastic Membrane Border and Plaque Composition in Native and Stented Segments ― An In Vivo and Histology-Based Study ―

      Background: Attenuation-compensated (AC) technique was recently introduced to improve the plaque characterization of optical coherence tomography (OCT). Histological validation demonstrated promising results but the efficacy and reproducibility of this technique for assessing in-vivo tissue composition remains unclear. Methods and Results: OCT images portraying native (n=200) and stented (n=200) segments and 31 histological cross-sections were analyzed. AC-OCT appeared superior to conventional (C)-OCT in detecting the external elastic lamina (EEM) borders (76% vs. 65.5%); AC-OCT enabled larger EEM arc detection compared with C-OCT (174.2±58.7° vs. 137.5±57.9°; P<0.001). There was poor ...

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    4. Optical Technology Stepping Forward ― Utility of Intracoronary Optical Coherence Tomography ―

      Optical Technology Stepping Forward ― Utility of Intracoronary Optical Coherence Tomography ―

      I ntravascular optical coherence tomography (OCT) is a light-based imaging modality that enables detailed visualization of the intraluminal structures in coronary arteries. High-resolution (10–20μm) cross-sectional images are generated by measuring the echo time delay and intensity of light that is reflected or backscattered from the internal structures in tissues.1,2 OCT is clinically useful during percutaneous coronary intervention (PCI) to assess lesion severity, optimize stent implantation, and characterize atherosclerotic plaques, including the identification of thin-cap fibroatheroma (TCFA) and lipid-rich plaques, which are reportedly responsible for periprocedural complications. OCT can also be used to assess the mechanism for ...

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      Mentions: Toshiro Shinke
    5. A Local Multi-Layer Model for Tissue Classification of in-vivo Atherosclerotic Plaques in Intravascular Optical Coherence Tomography

      A Local Multi-Layer Model for Tissue Classification of in-vivo Atherosclerotic Plaques in Intravascular Optical Coherence Tomography

      Clinical researches show that the morbidity of coronary artery disease (CAD) is gradually increasing in many countries every year, and it causes hundreds of thousands of people all over the world dying for each year. As the optical coherence tomography with high resolution and better contrast applied to the lesion tissue investigation of human vessel, many more micro-structures of the vessel could be easily and clearly visible to doctors, which help to improve the CAD treatment effect. Manual qualitative analysis and classification of vessel lesion tissue are time-consuming to doctors because a single-time intravascular optical coherence (IVOCT) data set of ...

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    6. Prevalence and Clinical Significance of Layered Plaque in Patients With Stable Angina Pectoris ― Evaluation With Histopathology and Optical Coherence Tomography ―

      Prevalence and Clinical Significance of Layered Plaque in Patients With Stable Angina Pectoris ― Evaluation With Histopathology and Optical Coherence Tomography ―

      Background: Healed plaques are identified as a layered pattern with optical coherence tomography (OCT) imaging, but the exact relationship between healed plaques and the development of significant coronary stenosis in stable angina pectoris (SAP) is not fully understood. Methods and Results: A retrospective clinincal study investigated the OCT characteristics of culprit lesions of SAP patients (n=205), and a prospective study examined the histopathological characteristics of layered plaque in directional coronary atherectomy (DCA) samples (42 samples from 18 SAP patients). In the retrospective study, layered plaque was observed in 36.6% of the SAP culprit lesions. Compared with patients with ...

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    7. Zero-Contrast Optical Coherence Tomography- and Physiology-Guided Percutaneous Coronary Intervention for Severely Calcified Lesion

      Zero-Contrast Optical Coherence Tomography- and Physiology-Guided Percutaneous Coronary Intervention for Severely Calcified Lesion

      An 80-year-old man with severe kidney dysfunction (estimated glomerular filtration rate, 26 mL/min/1.73 m 2 ) not requiring hemodialysis presented with effort angina. Diagnostic angiography with minimum contrast showed a diffuse lesion in the proximal right coronary artery (RCA; Figure A ). On a later day, optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) with dextran injection was performed. Because multiple cracks were seen in the severely calcified lesion after pre-dilation ( Figure B,C ; Supplementary Movie 1 ), an everolimus-eluting stent (3.25–33 mm) was implanted ( Figure D ). The final OCT showed sufficient luminal expansion (minimum stent area ...

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    8. Stabilization of High Risk Coronary Plaque on Optical Coherence Tomography and Near-Infrared Spectroscopy by Intensive Lipid-Lowering Therapy With Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) Inhibitor

      Stabilization of High Risk Coronary Plaque on Optical Coherence Tomography and Near-Infrared Spectroscopy by Intensive Lipid-Lowering Therapy With Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) Inhibitor

      A 70-year-old woman with hypertension and dyslipidemia underwent drug-eluting stent implantation in the mid-left anterior descending artery (LAD) due to acute coronary syndrome (ACS). Optical coherence tomography (OCT) during the index procedure showed lipid-rich plaque in non-culprit lesions of the proximal LAD and mid-right coronary artery (Figure B,E). Near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS) showed plaque with high lipid burden in both sites (Figure C,F). Intensive lipid-lowering therapy with combined strong statin and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor was started after the index procedure. Scheduled 10-month follow-up OCT and NIRS-IVUS showed increase in minimum fibrous cap thickness ...

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    9. Detection of enamel subsurface lesions by swept-source optical coherence tomography

      Detection of enamel subsurface lesions by swept-source optical coherence tomography

      This study aimed to non-destructively analyze the progression of subsurface enamel caries using swept-source optical coherence tomography (SS-OCT), a recently developed imaging analysis modality. Artificial enamel caries at various stages of demineralization were created in bovine tooth enamel using a modified lactic acid gel system. Untreated enamel served as a control. OCT images from cross-sections of enamel were collected. Mineral density, distribution, and histological changes were analyzed using an electron probe microanalyzer, scanning electron microscopy, and contact microradiography. The Raman spectrum and X-ray structural analysis of the enamel surfaces were determined. SS-OCT detected significant differences in mineral loss among the ...

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    10. Optical Coherence Tomography/Optical Frequency Domain Imaging: Imaging Application for Assessment of Human Carotid Plaque

      Optical Coherence Tomography/Optical Frequency Domain Imaging: Imaging Application for Assessment of Human Carotid Plaque

      Optical coherence tomography (OCT) is an intravascular imaging tool. Its high resolution facilitates detailed examination of intravascular morphological characteristics. In the coronary field, OCT systems are applied as practical clinical diagnostic method. In the carotid artery field, OCT is not covered by health insurance, and it is used as a research tool. We have published many reports on the morphological characteristics of carotid artery lesions on OCT or its application for carotid artery stenting. In this article, we review the application of OCT for carotid artery plaque and its usefulness.

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    11. Different Neoatherosclerosis Patterns in Drug-Eluting- and Bare-Metal Stent Restenosis ― Optical Coherence Tomography Study ―

      Different Neoatherosclerosis Patterns in Drug-Eluting- and Bare-Metal Stent Restenosis ― Optical Coherence Tomography Study ―

      Abstract Background: There are few reports about the differences between drug-eluting stents (DES) and bare metal stents (BMS) in neoatherosclerosis associated with in-stent restenosis (ISR), so we compared the frequency and characteristics of neoatherosclerosis with ISR evaluated by optical coherence tomography (OCT) in the present study. Methods and Results: Between March 2009 and November 2016, 98 consecutive patients with ISR who underwent diagnostic OCT were enrolled: 34 patients had a BMS, 34 had a 1st-generation DES, and 30 had a 2nd-generation DES. Neoatherosclerosis was defined as a lipid neointima (including a thin-cap fibroatheroma [TCFA] neointima, defined as a fibroatheroma with ...

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      Mentions: Osaka University
    12. High-accuracy endoscopic microscopy using a thin, 1.5 mm diameter probe with optical coherence tomography

      High-accuracy endoscopic microscopy using a thin, 1.5 mm diameter probe with optical coherence tomography

      We developed an endoscopic microscopy system with 20 nm accuracy that affords inspection through narrow gaps using a thin, 1.5 mm diameter probe. Accuracy was improved using Optical Coherence Tomography (OCT). The frequency modulated light source is stabilized with closed control from self-interference measurement. The probe is driven by two miniature motors, which allow three-dimensional scanning of an internal surface. Imaging performance is 60 frames per second. The high accuracy with narrow clearance capabilities of this system reduces the need for machine overhauls, which affords trustworthy daily inspections and hence greater machine reliability.

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    13. Effect of a coating material containing surface reaction-type pre-reacted glass-ionomer filler on prevention of primary enamel demineralization detected by optical coherence tomography

      Effect of a coating material containing surface reaction-type pre-reacted glass-ionomer filler on prevention of primary enamel demineralization detected by optical coherence tomography

      We used optical coherence tomography to examine the effect of a coating material containing surface reaction-type pre-reacted glass-ionomer (S-PRG) filler on primary enamel demineralization in 18 extracted human primary teeth. The pulp was removed, and each tooth was ultrasonically cleaned with distilled water. Six teeth were treated with 0.1-M lactic acid buffer solution (De group). In the second group (n = 6), a thin film of coating material was applied before demineralization (PRG group). A third group (Control group; n = 6) was maintained in artificial saliva. Using optical coherence tomography, we measured peak signal intensity (dB) and width at 1 ...

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    14. Assessment of root caries under wet and dry conditions using swept-source optical coherence tomography (SS-OCT)

      Assessment of root caries under wet and dry conditions using swept-source optical coherence tomography (SS-OCT)

      The purpose of this study was to compare optical properties of root caries under two observing conditions using swept-source optical coherence tomography (SS-OCT). In vitro and natural root caries were observed by SS-OCT under wet and dry conditions, followed by confocal laser scanning microscope (CLSM) and transverse microradiography (TMR). Signal intensity (SI), distance between SI peaks (SI-distance) and optical lesion depth were obtained from OCT. Lesion depth was measured from CLSM; lesion depth (LD TMR ) and mineral loss (ML) were obtained from TMR. In vitro root caries under wet and dry conditions showed different OCT images and SI patterns. Lesion ...

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    15. In vitro and clinical evaluation of optical coherence tomography for the detection of subgingival calculus and root cementum

      In vitro and clinical evaluation of optical coherence tomography for the detection of subgingival calculus and root cementum

      This study evaluated the effectiveness of swept-source optical coherence tomography (ss-OCT) for detecting calculus and root cementum during periodontal therapy. Optical coherence tomography (OCT) images were taken before and after removal of subgingival calculus from extracted teeth and compared with non-decalcified histological sections. Porcine gingival sheets of various thicknesses were applied to the root surfaces of extracted teeth with calculus and OCT images were taken. OCT images were also taken before and after scaling and root planing (SRP) in human patients. In vitro , calculus was clearly detected as a white-gray amorphous structure on the root surface, which disappeared after removal ...

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    16. Visualization of viscoelastic behavior in vivo skin using optical coherence tomography-based straingraphy combined with suction device

      Visualization of viscoelastic behavior in vivo skin using optical coherence tomography-based straingraphy combined with suction device

      Although various apparatuses have been developed to assess the skin mechanical function, the spatial viscoelastic behavior of each skin layer including the epidermis and dermis is yet unclear. To resolve that lack of clarity, we built a handmade system combining a suction device with optical coherence tomography (OCT). OCT can visualize the vertical section of the skin with high spatial resolution and high acquisition speed. In addition, we developed an algorithm for time-dependent strain tomography, named Dynamic Optical Coherence Straingraphy (D-OCSA), which can analyze the changes in strain distributions over time in sequential OCT images. Using the system, successive OCT ...

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    17. The Diagnosis of Spontaneous Coronary Artery Dissection by Optical Coherence Tomography

      The Diagnosis of Spontaneous Coronary Artery Dissection by Optical Coherence Tomography

      Spontaneous coronary artery dissection (SCAD) is rare, but it frequently presents as acute myocardial infarction. It is frequently fatal and most cases are diagnosed at autopsy. We herein present the case of a 65-year-old woman with ST-elevation and myocardial infarction due to SCAD. Optical coherence tomography (OCT) helped us to confirm the diagnosis. The information on the intravascular morphology provided by OCT imaging is much more detailed in comparison to that provided by coronary angiography (CAG) and intravascular ultrasound (IVUS).

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    18. Optical Coherence Tomography Assessment of Glucose Fluctuation Impact on the Neointimal Proliferation After Stent Implantation in a Diabetic/Hypercholesterolemic Swine Model

      Optical Coherence Tomography Assessment of Glucose Fluctuation Impact on the Neointimal Proliferation After Stent Implantation in a Diabetic/Hypercholesterolemic Swine Model

      The aim of the present study was to investigate the effects of glucose fluctuation on neointimal proliferation after stent implantation by optical coherence tomography (OCT) in a diabetic/hypercholesterolemic (DM/HC) swine model. A total of 24 everolimus-eluting stents (EES) were implanted in the right coronary artery (RCA) of the animals using a 20% overstretch ratio. The 24 swines were divided into a DM-high glucose fluctuation (HGF) group (n = 8), DMlow glucose fluctuation (LGF) group (n = 8), and a control group (n = 8). Percent diameter stenosis (%DS), late loss (LL), percent area stenosis (%AS), and neointimal thickness (NIT) were analyzed ...

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    19. Intravascular Images of Coronary Stenosis with Multiple Channels in a Patient with Antiphospholipid Syndrome: The Optical Coherence Tomography Findings

      Intravascular Images of Coronary Stenosis with Multiple Channels in a Patient with Antiphospholipid Syndrome: The Optical Coherence Tomography Findings

      Intravascular images of coronary stenosis by antiphospholipid syndrome (APS) would be beneficial to understand the mechanism of this disease. A 59-year-old woman with APS/systemic lupus erythematosis (SLE) underwent emergent coronary angiography which revealed stenosis with micro channels in the proximal left anterior descending artery. According to optical coherence tomography (OCT), the central lumen was surrounded by a thick septum with a homogenous and high intensity. Multiple small channels existed near the vessel wall with diffuse intimal hyperplasia. White thrombi were floating distal to the stenosis. Intravascular images obtained by optical coherence tomography (OCT) revealed the microstructure of complex coronary ...

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    20. Comparison between Preoperative Optical Coherence Tomography Findings of Carotid Artery Stenosis and Pathological Specimen of Removed Carotid Plaque: Case Report

      Comparison between Preoperative Optical Coherence Tomography Findings of Carotid Artery Stenosis and Pathological Specimen of Removed Carotid Plaque: Case Report

      Objective: Optical coherence tomography (OCT) has recently been applied for the characterization of carotid plaques, but few studies have compared OCT findings with findings from histopathologic examination of carotid plaques. We consider the accuracy, problems, and limitation of OCT findings by comparing OCT findings of carotid artery stenosis and pathological specimen of removed carotid plaque, and confirm that the interpretation of coronary artery findings of OCT can be applied to OCT findings of carotid artery plaque. Case Presentation: A 63-year-old man with asymptomatic left carotid stenosis underwent carotid endarterectomy (CEA). Findings for histopathologic assessment of excised plaque were compared with ...

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    1-24 of 113 1 2 3 4 5 »
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