64 research outputs found

    CT Scanning

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    Since its introduction in 1972, X-ray computed tomography (CT) has evolved into an essential diagnostic imaging tool for a continually increasing variety of clinical applications. The goal of this book was not simply to summarize currently available CT imaging techniques but also to provide clinical perspectives, advances in hybrid technologies, new applications other than medicine and an outlook on future developments. Major experts in this growing field contributed to this book, which is geared to radiologists, orthopedic surgeons, engineers, and clinical and basic researchers. We believe that CT scanning is an effective and essential tools in treatment planning, basic understanding of physiology, and and tackling the ever-increasing challenge of diagnosis in our society

    Reconstruction 3D personnalisée de la colonne vertébrale à partir d'images radiographiques non-calibrées

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    Les systèmes de reconstruction stéréo-radiographique 3D -- La colonne vertébrale -- La scoliose idiopathique adolescente -- Évolution des systèmes de reconstruction 3D -- Filtres de rehaussement d'images -- Techniques de segmentation -- Les méthodes de calibrage -- Les méthodes de reconstruction 3D -- Problématique, hypothèses, objectifs et méthode générale -- Three-dimensional reconstruction of the scoliotic spine and pelvis from uncalibrated biplanar X-ray images -- A versatile 3D reconstruction system of the spine and pelvis for clinical assessment of spinal deformities -- Simulation experiments -- Clinical validation -- A three-dimensional retrospective analysis of the evolution of spinal instrumentation for the correction of adolescent idiopathic scoliosis -- Auto-calibrage d'un système à rayons-X à partir de primitives de haut niveau -- Segmentation de la colonne vertébrale -- Approche hiérarchique d'auto-calibrage d'un système d'acquisition à rayons-X -- Personalized 3D reconstruction of the scoliotic spine from hybrid statistical and X-ray image-based models -- Validation protocol

    Left Ventricular Viability Maps : Fusion of Multimodal Images of Coronary Morphology and Functional Information

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    RÉSUMÉ Les maladies coronariennes demeurent encore la première cause de décès aux Etats-Unis étant donné que le taux de mortalité lié à ces maladies enregistré en 2005 est d’une personne sur cinq. Les sténoses (obstructions des artères coronaires) se manifestent par un rétrécissement du diamètre des coronaires, produisant une ischémie soit une réduction du flot sanguin vers le myocarde (le muscle cardiaque). Dans les cas les plus graves, les cellules qui composent le myocarde meurent définitivement et perdent leur fonction contractile. En présence de cette maladie les cliniciens ont recours à l’imagerie médicale pour étudier l’état du myocarde afin de déterminer si les cellules qui le composent sont mortes ou non ainsi que pour diagnostiquer les sténoses dans les coronaires. Actuellement, le clinicien utilise l’imagerie nucléaire pour étudier la perfusion du myocarde afin de déterminer son état. Une projection de cette information sur un modèle segmenté du myocarde, soit le modèle à 17-segments, établie le lien entre les zones atteintes et les coronaires qui sont les plus responsables de leur irrigation. Ce n’est que par la suite, lors d’une angiographie, que le clinicien pourra identifier les sténoses et possiblement intervenir par revascularisation. Une autre méthode de visualisation de la structure coronarienne et de la présence de sténoses est la méthode Green Lane. Le clinicien reproduit la structure des coronaires sur une carte circulaire en se basant sur l’angiographie. L’objectif de notre projet de recherche est de créer un modèle spécifique au patient où il serait possible de voir les territoires coronariens sur la surface du myocarde fusionnés avec la viabilité myocardique. Ce modèle s’adapterait au patient et permettrait l’étude d’autres groupes de coronaires, ce qui n’est pas possible avec le modèle à 17-segments qui est fixe et ne présente que les trois groupes principaux de coronaires (coronaire droite, gauche et circonflexe). De plus, ce modèle divise la surface de l’épicarde en segments à partir de données statistiques qui sont limitées par la nature et la représentativité de l’échantillon de la population considérée et ne permet pas de visualiser la distribution de perte de viabilité sur la surface épicardique.---------- ABSTRACT Coronary heart disease (CHD) can be attributed to the build up of plaque in the coronary arteries (atherosclerosis) which leads to ischemia, an insufficient supply of blood to the heart wall, which results in myocardial dysfunction. When ischemia remains untreated an infarction may appear (areas of necrosis in cardiac tissues) and consequently the heart’s contractility is affected, which may lead to death. This disease is the basis of one of every five deaths in the United States during 2005, elevating this disease to the largest cause of death in United States. In standard clinical practice, perfusion and viability studies allow clinicians to examine the extent and the severity of CHD over the myocardium. Then, by consulting a population-based coronary territory model, such as the 17-segment model, the clinician mentally integrates affected areas of myocardium, found in nuclear or magnetic resonance imaging, to coronaries that typically irrigate this region with blood. However, population-based models do not fit every patient. There are individuals whose coronary tree structure deviates from that of the majority of the population. In addition, the 17-segment model limits the number of coronary groups to three: left coronary artery (LAD), right coronary artery (RCA) and left circumflex (LCX). Moreover this map is not continuous; it divides the myocardial surface in segments.Our objective is therefore to create a patient-specific map explicitly combining coronary territories and myocardial viability. This continuous model would adapt to the patient and allow the study of groups of coronary unavailable with standard models. After having identified loss of viability, the clinician would use this model to infer the most likely obstructed coronary artery responsible for myocardial damage. Visualization of the loss of viability along with coronary structure would replace the physician’s task of mentally integrating information from various sources

    Book of Abstracts 15th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering and 3rd Conference on Imaging and Visualization

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    In this edition, the two events will run together as a single conference, highlighting the strong connection with the Taylor & Francis journals: Computer Methods in Biomechanics and Biomedical Engineering (John Middleton and Christopher Jacobs, Eds.) and Computer Methods in Biomechanics and Biomedical Engineering: Imaging and Visualization (JoãoManuel R.S. Tavares, Ed.). The conference has become a major international meeting on computational biomechanics, imaging andvisualization. In this edition, the main program includes 212 presentations. In addition, sixteen renowned researchers will give plenary keynotes, addressing current challenges in computational biomechanics and biomedical imaging. In Lisbon, for the first time, a session dedicated to award the winner of the Best Paper in CMBBE Journal will take place. We believe that CMBBE2018 will have a strong impact on the development of computational biomechanics and biomedical imaging and visualization, identifying emerging areas of research and promoting the collaboration and networking between participants. This impact is evidenced through the well-known research groups, commercial companies and scientific organizations, who continue to support and sponsor the CMBBE meeting series. In fact, the conference is enriched with five workshops on specific scientific topics and commercial software.info:eu-repo/semantics/draf

    Imaging Sensors and Applications

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    In past decades, various sensor technologies have been used in all areas of our lives, thus improving our quality of life. In particular, imaging sensors have been widely applied in the development of various imaging approaches such as optical imaging, ultrasound imaging, X-ray imaging, and nuclear imaging, and contributed to achieve high sensitivity, miniaturization, and real-time imaging. These advanced image sensing technologies play an important role not only in the medical field but also in the industrial field. This Special Issue covers broad topics on imaging sensors and applications. The scope range of imaging sensors can be extended to novel imaging sensors and diverse imaging systems, including hardware and software advancements. Additionally, biomedical and nondestructive sensing applications are welcome

    Application of Advanced MRI to Fetal Medicine and Surgery

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    Robust imaging is essential for comprehensive preoperative evaluation, prognostication, and surgical planning in the field of fetal medicine and surgery. This is a challenging task given the small fetal size and increased fetal and maternal motion which affect MRI spatial resolution. This thesis explores the clinical applicability of post-acquisition processing using MRI advances such as super-resolution reconstruction (SRR) to generate optimal 3D isotropic volumes of anatomical structures by mitigating unpredictable fetal and maternal motion artefact. It paves the way for automated robust and accurate rapid segmentation of the fetal brain. This enables a hierarchical analysis of volume, followed by a local surface-based shape analysis (joint spectral matching) using mathematical markers (curvedness, shape index) that infer gyrification. This allows for more precise, quantitative measurements, and calculation of longitudinal correspondences of cortical brain development. I explore the potential of these MRI advances in three clinical settings: fetal brain development in the context of fetal surgery for spina bifida, airway assessment in fetal tracheolaryngeal obstruction, and the placental-myometrial-bladder interface in placenta accreta spectrum (PAS). For the fetal brain, MRI advances demonstrated an understanding of the impact of intervention on cortical development which may improve fetal candidate selection, neurocognitive prognostication, and parental counselling. This is of critical importance given that spina bifida fetal surgery is now a clinical reality and is routinely being performed globally. For the fetal trachea, SRR can provide improved anatomical information to better select those pregnancies where an EXIT procedure is required to enable the fetal airway to be secured in a timely manner. This would improve maternal and fetal morbidity outcomes associated with haemorrhage and hypoxic brain injury. Similarly, in PAS, SRR may assist surgical planning by providing enhanced anatomical assessment and prediction for adverse peri-operative maternal outcome such as bladder injury, catastrophic obstetric haemorrhage and maternal death

    Characterization of alar ligament on 3.0T MRI: a cross-sectional study in IIUM Medical Centre, Kuantan

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    INTRODUCTION: The main purpose of the study is to compare the normal anatomy of alar ligament on MRI between male and female. The specific objectives are to assess the prevalence of alar ligament visualized on MRI, to describe its characteristics in term of its course, shape and signal homogeneity and to find differences in alar ligament signal intensity between male and female. This study also aims to determine the association between the heights of respondents with alar ligament signal intensity and dimensions. MATERIALS & METHODS: 50 healthy volunteers were studied on 3.0T MR scanner Siemens Magnetom Spectra using 2-mm proton density, T2 and fat-suppression sequences. Alar ligament is depicted in 3 planes and the visualization and variability of the ligament courses, shapes and signal intensity characteristics were determined. The alar ligament dimensions were also measured. RESULTS: Alar ligament was best depicted in coronal plane, followed by sagittal and axial planes. The orientations were laterally ascending in most of the subjects (60%), predominantly oval in shaped (54%) and 67% showed inhomogenous signal. No significant difference of alar ligament signal intensity between male and female respondents. No significant association was found between the heights of the respondents with alar ligament signal intensity and dimensions. CONCLUSION: Employing a 3.0T MR scanner, the alar ligament is best portrayed on coronal plane, followed by sagittal and axial planes. However, tremendous variability of alar ligament as depicted in our data shows that caution needs to be exercised when evaluating alar ligament, especially during circumstances of injury

    Case series of breast fillers and how things may go wrong: radiology point of view

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    INTRODUCTION: Breast augmentation is a procedure opted by women to overcome sagging breast due to breastfeeding or aging as well as small breast size. Recent years have shown the emergence of a variety of injectable materials on market as breast fillers. These injectable breast fillers have swiftly gained popularity among women, considering the minimal invasiveness of the procedure, nullifying the need for terrifying surgery. Little do they know that the procedure may pose detrimental complications, while visualization of breast parenchyma infiltrated by these fillers is also deemed substandard; posing diagnostic challenges. We present a case series of three patients with prior history of hyaluronic acid and collagen breast injections. REPORT: The first patient is a 37-year-old lady who presented to casualty with worsening shortness of breath, non-productive cough, central chest pain; associated with fever and chills for 2-weeks duration. The second patient is a 34-year-old lady who complained of cough, fever and haemoptysis; associated with shortness of breath for 1-week duration. CT in these cases revealed non thrombotic wedge-shaped peripheral air-space densities. The third patient is a 37‐year‐old female with right breast pain, swelling and redness for 2- weeks duration. Previous collagen breast injection performed 1 year ago had impeded sonographic visualization of the breast parenchyma. MRI breasts showed multiple non- enhancing round and oval shaped lesions exhibiting fat intensity. CONCLUSION: Radiologists should be familiar with the potential risks and hazards as well as limitations of imaging posed by breast fillers such that MRI is required as problem-solving tool

    Society for Cardiovascular Magnetic Resonance/European Society of Cardiovascular Imaging/American Society of Echocardiography/Society for Pediatric Radiology/North American Society for Cardiovascular Imaging Guidelines for the Use of Cardiac Magnetic Resonance in Pediatric Congenital and Acquired Heart Disease: Endorsed by The American Heart Association

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    Cardiovascular magnetic resonance has been utilized in the management and care of pediatric patients for nearly 40 years. It has evolved to become an invaluable tool in the assessment of the littlest of hearts for diagnosis, pre-interventional management and follow-up care. Although mentioned in a number of consensus and guidelines documents, an up-to-date, large, stand-alone guidance work for the use of cardiovascular magnetic resonance in pediatric congenital 36 and acquired 35 heart disease endorsed by numerous Societies involved in the care of these children is lacking. This guidelines document outlines the use of cardiovascular magnetic resonance in this patient population for a significant number of heart lesions in this age group and although admittedly, is not an exhaustive treatment, it does deal with an expansive list of many common clinical issues encountered in daily practice
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