All Articles from Andrew M. Rollins -Optical Coherence Tomography News

Articles from Andrew M. Rollins

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1. Feature Of The Week 1/20/13: CWRU Demonstrates Automatic Stent Detection in Intravascular OCT Images Using Bagged Decision Trees
  
  Explore Optical Coherence Tomography News Jan 20 2013 Cardiology
  
  Cardiovascular disease is the leading cause of death worldwide. Stent implantation by means of percutaneous coronary intervention is the most common coronary revascularization procedure. Intravascular Optical Coherence Tomography (iOCT) is the only imaging modality with the resolution and contrast necessary to enable accurate measurements of luminal architecture and neointima stent coverage. Manual analysis of intravascular OCT pullbacks is time consuming, limiting the size and number of studies that can be performed. We developed a highly automated method for detecting stent struts and measuring tissue coverage. Candidate struts were first identified using image processing techniques. We trained a bagged decision trees ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Marco A. Costa
2. 4D shear stress maps of the developing heart using Doppler optical coherence tomography
  
  Explore opticsinfobase.org Oct 31 2012 Developmental Biology , Doppler
  
  Accurate imaging and measurement of hemodynamic forces is vital for investigating how physical forces acting on the embryonic heart are transduced and influence developmental pathways. Of particular importance is blood flow-induced shear stress, which influences gene expression by endothelial cells and potentially leads to congenital heart defects through abnormal heart looping, septation, and valvulogenesis. However no imaging tool has been available to measure shear stress on the endocardium volumetrically and dynamically. Using 4D structural and Doppler OCT imaging, we are able to accurately measure the blood flow in the heart tube in vivo and to map endocardial shear stress throughout ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Michael W. Jenkins
3. Automatic stent detection in intravascular OCT images using bagged decision trees
  
  Explore opticsinfobase.org Oct 16 2012 Cardiology
  
  Intravascular optical coherence tomography (iOCT) is being used to assess viability of new coronary artery stent designs. We developed a highly automated method for detecting stent struts and measuring tissue coverage. We trained a bagged decision trees classifier to classify candidate struts using features extracted from the images. With 12 best features identified by forward selection, recall (precision) were 90%–94% (85%–90%). Including struts deemed insufficiently bright for manual analysis, precision improved to 94%. Strut detection statistics approached variability of manual analysis. Differences between manual and automatic area measurements were 0.12 ± 0.20 mm 2 and 0.11 ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Marco A. Costa
4. Post-doctoral Research Associate Positions in Translational OCT Imaging at Case Western Reserve University
  
  Explore Optical Coherence Tomography News Oct 5 2012 Jobs & Studentships
  
  The Department of Biomedical Engineering at Case Western Reserve University invites applications for post-doctoral Research Associate positions in translational optical coherence tomography (OCT) imaging. We are seeking sharp, enthusiastic, well-trained individuals who can contribute substantially to a highly collaborative research team focused on developing and translating clinical applications of OCT imaging. Project opportunities include application of endoscopic OCT imaging for guided therapeutics for cancer and cardiovascular disease. Applicants are expected to have an earned Ph.D. with relevant research experience. Specific expertise in OCT imaging and fiber-optic endoscopic applications is especially preferred, but the primary qualifications are outstanding technical proficiency ...
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  Mentions: Andrew M. Rollins Case Western Reserve University
5. Longitudinal Imaging of Heart Development With Optical Coherence Tomography
  
  Explore IEEE Xplore Jun 5 2012 Cardiology , Developmental Biology
  
  Optical coherence tomography (OCT) has great potential for deciphering the role of mechanics in normal and abnormal heart development. OCT images tissue microstructure and blood flow deep into the tissue (1-2 mm) at high spatiotemporal resolutions allowing unprecedented images of the developing heart. Here, we review the advancement of OCT technology to image heart development and report some of our recent findings utilizing OCT imaging under environmental control for longitudinal imaging. Precise control of the environment is absolutely required in longitudinal studies that follow the growth of the embryo or studies comparing normal versus perturbed heart development to obtain meaningful ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Michael W. Jenkins
6. Three-Dimensional Fourier-Domain Optical Coherence Tomography Imaging: Advantages and Future Development
  
  Explore SpringerLink Home Jun 3 2012 Cardiology
  
  Traditionally, intravascular imaging methods display the coronary anatomy in two dimensions, through a series of consecutive cross-sectional tomographic images. The physician is then required to mentally reassemble these images in order to visualize the vascular anatomy and all its complex interactions. The ability to depict the vascular structure with its actual spatial appearance, in three dimensions, is a powerful way to provide an easy, objective, and comprehensive overview of its complex and dynamic anatomy. However, three-dimensional (3D) application of intravascular imaging has been plagued by lack of enough resolution, frequent presence of imaging and motion artifacts and need for extensive ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Marco A. Costa
7. Quantification of fiber orientation in the canine atrial pacemaker complex using optical coherence tomography
  
  Explore Linking to Scitation Content May 18 2012 Cardiology
  
  The atrial pacemaker complex is responsible for the initiation and early propagation of cardiac impulses. Optical coherence tomography (OCT), a nondestructive imaging modality with spatial resolutions of ∼ 1 to 15 μm, can be used to identify unique fiber orientation patterns in this region of the heart. Functionally characterized canine sinoatrial nodes (SAN) (n = 7) were imaged using OCT up to ∼ 1 mm below the endocardial tissue surface. OCT images were directly compared to their corresponding histological sections. Fiber orientation patterns unique to the crista terminalis (CT), SAN, and surrounding atrial myocardium were identified with dominant average fiber angles of 89 ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Washington University in St. Louis
8. Volumetric quantification of fibrous caps using intravascular optical coherence tomography
  
  Explore opticsinfobase.org May 16 2012 Cardiology
  
  The rupture of thin-cap fibroatheroma accounts for most acute coronary events. Optical Coherence Tomography (OCT) allows quantification of fibrous cap (FC) thickness in vivo. Conventional manual analysis, by visually determining the thinnest part of the FC is subject to inter-observer variability and does not capture the 3-D morphology of the FC. We propose and validate a computer-aided method that allows volumetric analysis of FC. The radial FC boundary is semi-automatically segmented using a dynamic programming algorithm. The thickness at every point of the FC boundary, along with 3-D morphology of the FC, can be quantified. The method was validated against ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Marco A. Costa
9. In vivo intracardiac OCT imaging through percutaneous access: Towards image guided radio-frequency ablation
  
  Explore SPIE Digital Library Feb 17 2012 Cardiology
  
  BACKGROUND Complete catheter-tissue contact and permanent tissue destruction are essential for efficient radio-frequency ablation (RFA) during cardiac arrhythmia treatment. Current methods of monitoring lesion formation are indirect and unreliable. We aim to develop optical coherence tomography (OCT) as an imaging guidance for RFA. OBJECTIVES The purpose of this study is to evaluate the feasibility of using OCT catheter to image endocardia wall in active beating hearts through percutaneous access. This is a critical step toward image guided RFA in a clinic setting. METHODS A cone-scanning forward-viewing OCT catheter was advanced into active beating hearts through percutaneous access in four swine ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Hui Wang
10. Intravascular Optical Coherence Tomography Detection of Atherosclerosis and Inflammation in Murine Aorta
  
  Explore atvb.ahajournals.org Feb 5 2012 Cardiology
  
  Objective—The goal of this study was to evaluate the feasibility of imaging the aorta of apolipoprotein E–deficient (ApoE−/−) mice for the detection of atherosclerosis and macrophages using optical coherence tomography (OCT) compared with histology. Methods and Results—Atherosclerosis was induced by high-fat diet in 7-week-old ApoE−/− mice for 10 (n=7) and 22 (n=7) weeks. Nine-week-old ApoE−/− mice (n=7) fed a standard chow diet were used as controls. OCT images of a 10-mm descending aorta in situ were performed in 4 mice for each, and plaque and macrophages were determined at 0.5-mm intervals. Automated detection ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Marco A. Costa
11. Optical coherence tomography captures rapid hemodynamic responses to acute hypoxia of the embryonic cardiovascular system of Early Embryos
  
  Explore Wiley Online Library Jan 10 2012 Developmental Biology
  
  Background.The trajectory to heart defects may start in tubular and looping heart stages when detailed analysis of form and function is difficult by currently available methods. We used a novel method, Doppler optical coherence tomography (OCT), to follow changes in cardiovascular function in quail embryos during acute hypoxic stress. Chronic fetal hypoxia is a known risk factor for congenital heart diseases (CHDs). Decreased fetal heart rates during maternal obstructive sleep apnea suggest that studying fetal heart responses under acute hypoxia is warranted.Results.We captured responses to hypoxia at the critical looping heart stages. Doppler OCT revealed detailed vitelline ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Michael W. Jenkins
12. Congratulations to Zhao Wang from CWRU a Winner of a 2012 Student Travel Grant Award
  
  Explore Optical Coherence Tomography News Jan 9 2012 Cardiology
  
  Zhao Wang from Case Western Reserve University is one of four winners of the OCT News 2012 student travel grant awards (see prior announcement Here). Below is a summary of his work. Coronary artery disease is the leading cause of death worldwide. The rupture of thin-cap fibroatheroma (TCFA) accounts for most acute coronary events. Optical Coherence Tomography (OCT) is able to quantify the fibrous cap (FC) thickness in vivo. Conventional analysis measuring the thinnest part of the FC is subject to inter-observer variability and does not capture the 3-D morphology of the FC. The aim of this study is to ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Marco A. Costa
13. In vivo intracardiac optical coherence tomography imaging through percutaneous access: toward image-guided radio-frequency ablation
  
  Explore SPIE Digital Library Nov 8 2011 Cardiology
  
  Complete catheter-tissue contact and permanent tissue destruction are essential for efficient radio-frequency ablation (RFA) during cardiac arrhythmia treatment. Current methods of monitoring lesion formation are indirect and unreliable. The purpose of this study is to evaluate the feasibility of using optical coherence tomography (OCT) catheter to image endocardial wall in actively beating hearts through percutaneous access. We reported the first in vivo intracardiac OCT imaging through percutaneous access with a thin and flexible OCT catheter. This is a critical step toward image-guided RFA in a clinical setting. A cone-scanning forward-viewing OCT catheter was advanced into beating hearts through percutaneous access ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Hui Wang
14. Motion artifacts associated with in vivo endoscopic OCT images of the esophagus
  
  Explore opticsinfobase.org Oct 4 2011 Gastroenterology
  
  3-D optical coherence tomography (OCT) has been extensively investigated as a potential screening and/or surveillance tool for Barrett’s esophagus (BE). Understanding and correcting motion artifact may improve image interpretation. In this work, the motion trace was analyzed to show the physiological origin (respiration and heart beat) of the artifacts. Results showed that increasing balloon pressure did not sufficiently suppress the physiological motion artifact. An automated registration algorithm was designed to correct such artifacts. The performance of the algorithm was evaluated in images of normal porcine esophagus and demonstrated in images of BE in human patients.
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  Mentions: Andrew M. Rollins Case Western Reserve University Hui Wang
15. Using optical coherence tomography for the longitudinal non-invasive evaluation of epidermal thickness in a murine model of chronic skin inflammation
  
  Explore Wiley Online Library Sep 14 2011 Dermatology
  
  Background Non-invasive methods are desirable for longitudinal studies examining drug efficacy and disease resolution defined as decreases in epidermal thickness in mouse models of psoriasiform skin disease. This would eliminate the need for either sacrificing animals or collecting serial skin biopsies to evaluate changes in disease progression during an individual study. The quantitation of epidermal thickness using optical coherence tomography (OCT) provides an alternative to traditional histology techniques. Methods Using the KC-Tie2 doxycycline-repressible psoriasiform skin disease mouse model, OCT imaging was completed on diseased back skin of adult KC-Tie2 (n = 3–4) and control (n = 3–4) mice, followed immediately ...
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  Mentions: Andrew M. Rollins National Institutes of Health Case Western Reserve University
16. Optical Coherence Tomography and Fibrous Cap Characterization
  
  Explore SpringerLink Home May 11 2011 Cardiology
  
  The pathophysiology of acute coronary syndromes has long been associated with atherosclerotic plaque rupture. Inflammation, thinning, and disruption of the fibrous cap have been implicated with the final processes leading to plaque rupture, but confirmation of these mechanisms of coronary thrombosis in humans has been hampered by the lack of imaging methods with sufficient resolution to resolve fibrous cap characterization and thickness in vivo. Intravascular optical coherence tomography (OCT) provides images with micron-level axial and lateral resolution, enabling detailed visualization of micro-structural changes of the arterial wall. The present article provides an overview of the potential role of OCT in ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Marco A. Costa
17. Method for measuring biomechanical properties in an eye
  
  Explore uspto.gov May 3 2011 Ophthalmology , Patents
  
  Systems and methods are provided for characterizing biomechanical properties of tissue within an eye. A perturbation component introduces a stress to the eye tissue. An imaging component is operative to obtain an image of the eye tissue. A first image of the tissue can be obtained prior to the introduction of the stress and a second image of the tissue can be obtained after the introduction of the stress. An image analysis component compares the first image and the second image as to determine at least one biomechanical property of the tissue.
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  Mentions: Andrew M. Rollins Case Western Reserve University Cleveland Clinic
18. Even frequency spacing spectrometer and optical coherence tomography device
  
  Explore uspto.gov Apr 19 2011 Patents
  
  This application describes a spectrometer that includes a set of collimating optics to collimate received EMR to produce a collimated EMR. The spectrometer also includes a first dispersive optical element for dispersing the collimated EMR and a second dispersive optical element spaced apart from the first dispersive optical element to produce further dispersed EMR. The first dispersive optical element and the second dispersive optical element cooperate to disperse received EMR into a plurality of even frequency spaced EMR spectra. The spectrometer also includes a detector positioned to receive the EMR after passing though an optical path that includes the set ...
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  Mentions: Andrew M. Rollins Case Western Reserve University
19. Optical Coherence Tomography Imaging of Early Quail Embryos
  
  Explore Cold Spring Harbor Protocols Feb 3 2011 Developmental Biology
  
  Congenital heart defects (CHDs) affect thousands of newborns each year in the United States. Recent research using animal model systems indicates that the abnormal function of the early tubular heart precedes structural defects such as septal defects. Optical coherence tomography (OCT) is an imaging modality that can provide high spatial and temporal resolution to study both the structure and the function of the tubular heart. With technical advances in OCT imaging speed, especially with frequency domain OCT and image-based retrospective gating, it is now possible to image a beating avian embryonic heart in three dimensions under physiological conditions and follow ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Michael W. Jenkins
20. High-Speed Optical Coherence Tomography Imaging of the Beating Avian Embryonic Heart
  
  Explore Cold Spring Harbor Protocols Feb 3 2011 Developmental Biology
  
  Congenital heart defects (CHDs) affect thousands of newborns each year in the United States. Recent research using animal model systems indicates that the abnormal function of the early tubular heart precedes structural defects such as septal defects. Optical coherence tomography (OCT) is an imaging modality that can provide high spatial and temporal resolution to study both the structure and the function of the tubular heart. With technical advances in OCT imaging speed, especially with frequency domain OCT and image-based retrospective gating, it is now possible to image a beating avian embryonic heart in three dimensions under physiological conditions and follow ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Michael W. Jenkins
21. Method for optical coherence elastography of the cornea
  
  Explore SPIE Digital Library Jan 24 2011 Ophthalmology
  
  The material properties of the cornea are important determinants of corneal shape and refractive power. Corneal ectatic diseases, such as keratoconus, are characterized by material property abnormalities, are associated with progressive thinning and distortion of the cornea, and represent a leading indication for corneal transplantation. We describe a corneal elastography technique based on optical coherence tomography (OCT) imaging, in which displacement of intracorneal optical features is tracked with a 2-D cross-correlation algorithm as a step toward nondestructive estimation of local and directional corneal material properties. Phantom experiments are performed to measure the effects of image noise and out-of-plane displacement on ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Cleveland Clinic
22. Three-Dimensional Imaging of Ureter With Endoscopic Optical Coherence Tomography
  
  Explore ScienceDirect Jan 23 2011 Urology
  
  Objectives To verify the ability to identify the layered structures of the ureteral wall and to image a segment of the ureter in 3 dimensions with high-speed, endoscopic optical coherence tomography (EOCT). Methods We imaged a porcine ureter ex vivo using a spectral-domain EOCT with a specially designed circumferential scanning fiber catheter. The images were correlated with the histologic findings to identify the corresponding structures. Three-dimensional images and en face images at different depths from the luminal surface were reconstructed from the multiple cross-sectional images to visualize the layered structure of a segment of the ureter from different perspectives. Results ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Wei Kang
23. Blood Flow Dynamics of One Cardiac Cycle and Relationship to Mechanotransduction and Trabeculation during Heart Looping
  
  Explore AJP - Heart and Circulatory Physiology Jan 15 2011 Cardiology
  
  Analyses of form-function relationships during heart looping are directly related to technological advances. Recent advances in 4-D optical coherence tomography (OCT) permit observations of cardiac dynamics at high speed acquisition rates and high resolution. Real-time observation of the avian stage 13 looping heart reveals that interactions between the endocardial and myocardial compartments are more complex than previously depicted. Here we applied 4-D OCT to elucidate the relationships of the endocardium, myocardium, and cardiac jelly compartments in a single cardiac cycle during looping. Six cardiac levels along the longitudinal heart tube were each analyzed at 15 time points from diastole to ...
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  Mentions: Andrew M. Rollins Massachusetts Institute of Technology James G. Fujimoto
24. Diagnostic efficacy of computer extracted image features in optical coherence tomography of the precancerous cervix
  
  Explore Medical Physics Dec 16 2010 Gynecology , Oncology
  
  Purpose: To determine the diagnostic efficacy of optical coherence tomography (OCT) to identify cervical intraepithelial neoplasia (CIN) grade 2 or higher by computer-aided diagnosis (CADx). Methods: OCT has been investigated as a screening/diagnostic tool in the management of preinvasive and early invasive cancers of the uterine cervix. In this study, an automated algorithm was developed to extract OCT image features and identify CIN 2 or higher. First, the cervical epithelium was detected by a combined watershed and active contour method. Second, four features were calculated: The thickness of the epithelium and its standard deviation and the contrast between the ...
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  Mentions: Andrew M. Rollins Case Western Reserve University Cleveland Clinic
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