1. Articles from Hyeong Soo Nam

    1-14 of 14
    1. Comprehensive Assessment of High-Risk Plaques by Dual-Modal Imaging Catheter in Coronary Artery

      Comprehensive Assessment of High-Risk Plaques by Dual-Modal Imaging Catheter in Coronary Artery

      Coronary plaque destabilization involves alterations in microstructure and biochemical composition; however, no imaging approach allows such comprehensive characterization. Herein, the authors demonstrated a simultaneous microstructural and biochemical assessment of high-risk plaques in the coronary arteries in a beating heart using a fully integrated optical coherence tomography and fluorescence lifetime imaging (FLIm). It was found that plaque components such as lipids, macrophages, lipids+macrophages, and fibrotic tissues had unique fluorescence lifetime signatures that were distinguishable using multispectral FLIm. Because FLIm yielded massive biochemical readouts, the authors incorporated machine learning framework into FLIm, and ultimately, their approach enabled an automated, quantitative imaging ...

      Read Full Article
    2. In Vivo Cellular-Level 3D Imaging of Peripheral Nerves Using a Dual-Focusing Technique for Intra-Neural Interface Implantation

      In Vivo Cellular-Level 3D Imaging of Peripheral Nerves Using a Dual-Focusing Technique for Intra-Neural Interface Implantation

      In vivo volumetric imaging of the microstructural changes of peripheral nerves with an inserted electrode could be key for solving the chronic implantation failure of an intra-neural interface necessary to provide amputated patients with natural motion and sensation. Thus far, no imaging devices can provide a cellular-level three-dimensional (3D) structural images of a peripheral nerve in vivo. In this study, an optical coherence tomography-based peripheral nerve imaging platform that employs a newly proposed depth of focus extension technique is reported. A point spread function with the finest transverse resolution of 1.27 µm enables the cellular-level volumetric visualization of the ...

      Read Full Article
    3. Macrophage targeted theranostic strategy for accurate detection and rapid stabilization of the inflamed high-risk plaque

      Macrophage targeted theranostic strategy for accurate detection and rapid stabilization of the inflamed high-risk plaque

      Rationale: Inflammation plays a pivotal role in the pathogenesis of the acute coronary syndrome. Detecting plaques with high inflammatory activity and specifically treating those lesions can be crucial to prevent life-threatening cardiovascular events. Methods: Here, we developed a macrophage mannose receptor (MMR)-targeted theranostic nanodrug (mannose-polyethylene glycol-glycol chitosan-deoxycholic acid-cyanine 7-lobeglitazone; MMR-Lobe-Cy) designed to identify inflammatory activity as well as to deliver peroxisome proliferator-activated gamma (PPARγ) agonist, lobeglitazone, specifically to high-risk plaques based on the high mannose receptor specificity. The MMR-Lobe-Cy was intravenously injected into balloon-injured atheromatous rabbits and serial in vivo optical coherence tomography (OCT)-near-infrared fluorescence (NIRF) structural-molecular imaging ...

      Read Full Article
      Mentions: Korea University
    4. Imaging catheter system

      Imaging catheter system

      Disclosed is an imaging catheter system that utilizes optical coherence tomography and autofluorescence lifetime imaging microscopy. The disclosed imaging catheter system may include: an autofluorescence light source; an OCT device; a catheter device configured to receive rays inputted from the autofluorescence light source and an OCT light source of the OCT device and scan a specimen; an optical detector unit configured to detect autofluorescence generated from the specimen; and a first optics system configured to transfer the autofluorescence to the optical detector unit and transfer a ray of the OCT light source reflected from the specimen to the OCT device.

      Read Full Article
    5. Full-field OCT system using wavelength-tunable laser and three-dimensional image correction method

      Full-field OCT system using wavelength-tunable laser and three-dimensional image correction method

      The present disclosure provides a full-field OCT system using a wavelength-tunable laser, which can observe peaks of a short-time A-line profile corresponding to each time point at which interference images of an object to be measured are acquired, so as to measure a depth direction movement of the object to be measured, and can correct the phases of interference signals on the basis of the measured depth direction movement, so as to generate an OCT image which is compensated for the depth direction movement.

      Read Full Article
    6. Comprehensive intravascular imaging of atherosclerotic plaque in vivo using optical coherence tomography and fluorescence lifetime imaging

      Comprehensive intravascular imaging of atherosclerotic plaque in vivo using optical coherence tomography and fluorescence lifetime imaging

      Comprehensive imaging of both the structural and biochemical characteristics of atherosclerotic plaque is essential for the diagnosis and study of coronary artery disease because both a plaque’s morphology and its biochemical composition affect the level of risk it poses. Optical coherence tomography (OCT) and fluorescence lifetime imaging (FLIm) are promising optical imaging methods for characterizing coronary artery plaques morphologically and biochemically, respectively. In this study, we present a hybrid intravascular imaging device, including a custom-built OCT/FLIm system, a hybrid optical rotary joint, and an imaging catheter, to visualize the structure and biochemical composition of the plaque in an ...

      Read Full Article
    7. Multispectral analog-mean-delay fluorescence lifetime imaging combined with optical coherence tomography

      Multispectral analog-mean-delay fluorescence lifetime imaging combined with optical coherence tomography

      The pathophysiological progression of chronic diseases, including atherosclerosis and cancer, is closely related to compositional changes in biological tissues containing endogenous fluorophores such as collagen, elastin, and NADH, which exhibit strong autofluorescence under ultraviolet excitation. Fluorescence lifetime imaging (FLIm) provides robust detection of the compositional changes by measuring fluorescence lifetime, which is an inherent property of a fluorophore. In this paper, we present a dual-modality system combining a multispectral analog-mean-delay (AMD) FLIm and a high-speed swept-source optical coherence tomography (OCT) to simultaneously visualize the cross-sectional morphology and biochemical compositional information of a biological tissue. Experiments using standard fluorescent solutions showed ...

      Read Full Article
    8. Endoscopic micro-optical coherence tomography with extended depth of focus using a binary phase spatial filter

      Endoscopic micro-optical coherence tomography with extended depth of focus using a binary phase spatial filter

      Micro-optical coherence tomography (μOCT) is an advanced imaging technique that acquires a three-dimensional microstructure of biological samples with a high spatial resolution, up to 1 μm, by using a broadband light source and a high numerical aperture (NA) lens. As high NA produces a short depth of focus (DOF), extending the DOF is necessary to obtain a reasonable imaging depth. However, due to the complexity of optics and the limited space, it has been challenging to fabricate endoscopic μOCT, which is essential for clinical translation. Here, we report an endoscopic μOCT probe with an extended DOF by using a binary ...

      Read Full Article
    9. Characterization of lipid-rich plaques using spectroscopic optical coherence tomography

      Characterization of lipid-rich plaques using spectroscopic optical coherence tomography

      Intravascular optical coherence tomography (IV-OCT) is a high-resolution imaging method used to visualize the internal structures of walls of coronary arteries in vivo . However, accurate characterization of atherosclerotic plaques with gray-scale IV-OCT images is often limited by various intrinsic artifacts. In this study, we present an algorithm for characterizing lipid-rich plaques with a spectroscopic OCT technique based on a Gaussian center of mass (GCOM) metric. The GCOM metric, which reflects the absorbance properties of lipids, was validated using a lipid phantom. In addition, the proposed characterization method was successfully demonstrated in vivo using an atherosclerotic rabbit model and was found ...

      Read Full Article
    10. Automated detection of vessel lumen and stent struts in intravascular optical coherence tomography to evaluate stent apposition and neointimal coverage

      Automated detection of vessel lumen and stent struts in intravascular optical coherence tomography to evaluate stent apposition and neointimal coverage

      Purpose: Intravascular optical coherence tomography (IV-OCT) is a high-resolution imaging method used to visualize the microstructure of arterial walls in vivo . IV-OCT enables the clinician to clearly observe and accurately measure stent apposition and neointimal coverage of coronary stents, which are associated with side effects such as in-stent thrombosis. In this study, the authors present an algorithm for quantifying stent apposition and neointimal coverage by automatically detecting lumen contours and stent struts in IV-OCT images. Methods: The algorithm utilizes OCT intensity images and their first and second gradient images along the axial direction to detect lumen contours and stent strut ...

      Read Full Article
    11. Intracoronary dual-modal optical coherence tomography-near-infrared fluorescence structural–molecular imaging with a clinical dose of indocyanine green for the assessment of high-risk plaques and stent-associated inflammation in a beating coronary artery

      Intracoronary dual-modal optical coherence tomography-near-infrared fluorescence structural–molecular imaging with a clinical dose of indocyanine green for the assessment of high-risk plaques and stent-associated inflammation in a beating coronary artery

      Aims Inflammation plays essential role in development of plaque disruption and coronary stent-associated complications. This study aimed to examine whether intracoronary dual-modal optical coherence tomography (OCT)-near-infrared fluorescence (NIRF) structural–molecular imaging with indocyanine green (ICG) can estimate inflammation in swine coronary artery. Methods and results After administration of clinically approved NIRF-enhancing ICG (2.0 mg/kg) or saline, rapid coronary imaging (20 mm/s pullback speed) using a fully integrated OCT-NIRF catheter was safely performed in 12 atheromatous Yucatan minipigs and in 7 drug-eluting stent (DES)-implanted Yorkshire pigs. Stronger NIRF activity was identified in OCT-proven high-risk plaque compared ...

      Read Full Article
    12. A bi-directional assessment of spontaneous coronary artery dissection by three-dimensional flythrough rending of optical coherence tomography images

      A bi-directional assessment of spontaneous coronary artery dissection by three-dimensional flythrough rending of optical coherence tomography images

      A 71-year-old woman was admitted to our hospital due to unstable chest pain. Coronary angiography demonstrated a complex eccentric lesion with 80% narrowing of the right coronary arterial lumen ( Panel A ). Intravascular optical coherence tomography (IV-OCT) revealed typical characteristics of spontaneous coronary artery...

      Read Full Article
    13. Feature Of The Week 8/31/14: Fully Integrated High-speed Intravascular OCT/NIRF Structural/Molecular Imaging In Vivo using a Clinically-available NIRF Emitting Indocyanine Green to Detect Inflamed Lipid-rich Atheromata in Coronary-sized Vessels

      Feature Of The Week 8/31/14: Fully Integrated High-speed Intravascular OCT/NIRF Structural/Molecular Imaging In Vivo using a Clinically-available NIRF Emitting Indocyanine Green to Detect Inflamed Lipid-rich Atheromata in Coronary-sized Vessels

      In current study, we fully integrated near-infrared fluorescence (NIRF) molecular imaging into intravascular OCT structural imaging. The OCT/NIRF single catheter imaging clearly demonstrated the microstructure of atheromata and simultaneously identified ICG-enhancing macrophage abundant lipid-rich areas of the plaques. Ex vivo NIRF imaging evidently validated in vivo OCT-NIRF imaging. NIRF signals on ex vivo fluorescence reflectance imaging colocalized well with in vivo NIRF imaging. In vitro ICG cell uptake, correlative fluorescence microscopy, and histopathology corroborated the in vivo imaging findings. Herein, our research team have solved the issues critical for application of this OCT/NIRF imaging technology to clinical practice ...

      Read Full Article
    14. Fully Integrated High-Speed Intravascular OCT/NIRF Structural/Molecular Imaging In Vivo Using a Clinically Available Near-Infrared Fluorescence–Emitting Indocyanine Green to Detect Inflamed Lipid-Rich Atheromata in Coronary-Sized Vessels

      Fully Integrated High-Speed Intravascular OCT/NIRF Structural/Molecular Imaging In Vivo Using a Clinically Available Near-Infrared Fluorescence–Emitting Indocyanine Green to Detect Inflamed Lipid-Rich Atheromata in Coronary-Sized Vessels

      Background— Lipid-rich inflamed coronary plaques a reprone to rupture. The purpose of this study was to assess lipid-rich inflamed plaques invivo using fully integrated high-speed optical coherence tomography (OCT)/ near-infrared fluorescence (NIRF) molecular imaging with a Food and Drug Administration– a pproved indocyanine green (ICG). Methods a nd Results— A n integrated high-speed intravascular OCT/NIRF imaging c a theter a nd a du a l-mod a l OCT/NIRF system were constructed b a sed on a cl in ic a l OCT pl a tform. For imaging lipid-rich inflamed plaques, the Food and Drug Administration– approved NIRF-emitting ICG ...

      Read Full Article
    1-14 of 14
  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
  2. Topics in the News

    1. (11 articles) Korea University
    2. (11 articles) Hanyang University
    3. (9 articles) Korea Advanced Institute of Science and Technology
    4. (2 articles) FDA
  3. Popular Articles

  4. Picture Gallery

    Fully Integrated High-Speed Intravascular OCT/NIRF Structural/Molecular Imaging In Vivo Using a Clinically Available Near-Infrared Fluorescence–Emitting Indocyanine Green to Detect Inflamed Lipid-Rich Atheromata in Coronary-Sized Vessels Feature Of The Week 8/31/14: Fully Integrated High-speed Intravascular OCT/NIRF Structural/Molecular Imaging In Vivo using a Clinically-available NIRF Emitting Indocyanine Green to Detect Inflamed Lipid-rich Atheromata in Coronary-sized Vessels A bi-directional assessment of spontaneous coronary artery dissection by three-dimensional flythrough rending of optical coherence tomography images Intracoronary dual-modal optical coherence tomography-near-infrared fluorescence structural–molecular imaging with a clinical dose of indocyanine green for the assessment of high-risk plaques and stent-associated inflammation in a beating coronary artery Automated detection of vessel lumen and stent struts in intravascular optical coherence tomography to evaluate stent apposition and neointimal coverage Characterization of lipid-rich plaques using spectroscopic optical coherence tomography Endoscopic micro-optical coherence tomography with extended depth of focus using a binary phase spatial filter Multispectral analog-mean-delay fluorescence lifetime imaging combined with optical coherence tomography Comprehensive intravascular imaging of atherosclerotic plaque in vivo using optical coherence tomography and fluorescence lifetime imaging Full-field OCT system using wavelength-tunable laser and three-dimensional image correction method Association of retinal thickness and microvasculature with cognitive performance and brain volumes in elderly adults A Deep Learning Framework for the Detection and Quantification of Reticular Pseudodrusen and Drusen on Optical Coherence Tomography