Download or read book Signal Processing Tools of MRI Perfusion weighted Imaging Data Analysis written by Yang Wu and published by . This book was released on 2005 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keywords: flow heterogeneity, vasucular transport function, CBF, recirculation, DSC, MRI, Perfusion-weighted imaging.

Download or read book Signal Processing Tools of MRI Perfusion weighted Imaging Data Analysis written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In dynamic susceptibility contrast (DSC) magnetic resonance (MR) approaches, by injecting a bolus of paramagnetic contrast agent intravenously, the measured MR signal is converted to a concentration time course to estimate hemodynamic parameters like cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT). Before estimating hemodynamic parameters, recirculation effects need to be removed by a gamma-variate fit of the concentration curve. In this dissertation, however, it has been found and demonstrated by simulation that fitting may not discern recirculation from the first-pass in case of cerebral ischemia. A new methodology using temporal independent component analysis (ICA) to remove recirculation in both normal and ischemic brain tissues while preserving the first-pass is therefore proposed. This should improve hemodynamics accuracy particularly in ischemic lesions. In DSC MR approaches, bolus delays between the arterial input function (AIF) and tissue curves may induce significant CBF quantification error. Our second contribution is using ICA to estimate bolus arrival time for each 5x5 region of interest (ROI) throughout the brain parenchyma. A global AIF measured from a major artery can then be shifted in accordance to define a local AIF for each ROI. The bolus delay may therefore be minimized, and the general shape of the AIF is preserved. This should improve the flow quantification. Transfer function has been widely used to characterize an unknown system. In DSC MR approaches, vascular transfer function (VTF) represents the probability density function of the vascular transit time. Our third contribution is to propose a new tool to estimate intracranial VTF non-invasively. This should provide an alternative means of assessing tissue perfusion status, particularly in patients with cerebrovascular diseases. Bolus dispersion between the AIF and tissue curves may induce flow quantification error, which cannot be minimized without the kno.

Download or read book Signal Processing for Magnetic Resonance Imaging and Spectroscopy written by Hong Yan and published by CRC Press. This book was released on 2002-02-20 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: This reference/text contains the latest signal processing techniques in magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) for more efficient clinical diagnoses-providing ready-to-use algorithms for image segmentation and analysis, reconstruction and visualization, and removal of distortions and artifacts for increased detec

Download or read book Statistical Analysis of Noise in MRI written by Santiago Aja-Fernández and published by Springer. This book was released on 2016-07-12 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique text presents a comprehensive review of methods for modeling signal and noise in magnetic resonance imaging (MRI), providing a systematic study, classifying and comparing the numerous and varied estimation and filtering techniques. Features: provides a complete framework for the modeling and analysis of noise in MRI, considering different modalities and acquisition techniques; describes noise and signal estimation for MRI from a statistical signal processing perspective; surveys the different methods to remove noise in MRI acquisitions from a practical point of view; reviews different techniques for estimating noise from MRI data in single- and multiple-coil systems for fully sampled acquisitions; examines the issue of noise estimation when accelerated acquisitions are considered, and parallel imaging methods are used to reconstruct the signal; includes appendices covering probability density functions, combinations of random variables used to derive estimators, and useful MRI datasets.

Download or read book Quantitative Magnetic Resonance Imaging written by Nicole Seiberlich and published by Academic Press. This book was released on 2020-11-18 with total page 1094 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantitative Magnetic Resonance Imaging is a 'go-to' reference for methods and applications of quantitative magnetic resonance imaging, with specific sections on Relaxometry, Perfusion, and Diffusion. Each section will start with an explanation of the basic techniques for mapping the tissue property in question, including a description of the challenges that arise when using these basic approaches. For properties which can be measured in multiple ways, each of these basic methods will be described in separate chapters. Following the basics, a chapter in each section presents more advanced and recently proposed techniques for quantitative tissue property mapping, with a concluding chapter on clinical applications. The reader will learn: - The basic physics behind tissue property mapping - How to implement basic pulse sequences for the quantitative measurement of tissue properties - The strengths and limitations to the basic and more rapid methods for mapping the magnetic relaxation properties T1, T2, and T2* - The pros and cons for different approaches to mapping perfusion - The methods of Diffusion-weighted imaging and how this approach can be used to generate diffusion tensor - maps and more complex representations of diffusion - How flow, magneto-electric tissue property, fat fraction, exchange, elastography, and temperature mapping are performed - How fast imaging approaches including parallel imaging, compressed sensing, and Magnetic Resonance - Fingerprinting can be used to accelerate or improve tissue property mapping schemes - How tissue property mapping is used clinically in different organs - Structured to cater for MRI researchers and graduate students with a wide variety of backgrounds - Explains basic methods for quantitatively measuring tissue properties with MRI - including T1, T2, perfusion, diffusion, fat and iron fraction, elastography, flow, susceptibility - enabling the implementation of pulse sequences to perform measurements - Shows the limitations of the techniques and explains the challenges to the clinical adoption of these traditional methods, presenting the latest research in rapid quantitative imaging which has the possibility to tackle these challenges - Each section contains a chapter explaining the basics of novel ideas for quantitative mapping, such as compressed sensing and Magnetic Resonance Fingerprinting-based approaches

Download or read book Pattern Recognition and Signal Analysis in Medical Imaging written by Anke Meyer-Baese and published by Elsevier. This book was released on 2014-03-21 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: Medical imaging is one of the heaviest funded biomedical engineering research areas. The second edition of Pattern Recognition and Signal Analysis in Medical Imaging brings sharp focus to the development of integrated systems for use in the clinical sector, enabling both imaging and the automatic assessment of the resultant data. Since the first edition, there has been tremendous development of new, powerful technologies for detecting, storing, transmitting, analyzing, and displaying medical images. Computer-aided analytical techniques, coupled with a continuing need to derive more information from medical images, has led to a growing application of digital processing techniques in cancer detection as well as elsewhere in medicine. This book is an essential tool for students and professionals, compiling and explaining proven and cutting-edge methods in pattern recognition for medical imaging. - New edition has been expanded to cover signal analysis, which was only superficially covered in the first edition - New chapters cover Cluster Validity Techniques, Computer-Aided Diagnosis Systems in Breast MRI, Spatio-Temporal Models in Functional, Contrast-Enhanced and Perfusion Cardiovascular MRI - Gives readers an unparalleled insight into the latest pattern recognition and signal analysis technologies, modeling, and applications

Download or read book Susceptibility Weighted Imaging in MRI written by E. Mark Haacke and published by John Wiley & Sons. This book was released on 2014-03-25 with total page 817 pages. Available in PDF, EPUB and Kindle. Book excerpt: MRI Susceptibility Weighted Imaging discusses the promising new MRI technique called Susceptibility Weighted Imaging (SWI), a powerful tool for the diagnosis and treatment of acute stroke, allowing earlier detection of acute stroke hemorrhage and easier detection of microbleeds in acute ischemia. The book is edited by the originators of SWI and features contributions from the top leaders in the science. Presenting an even balance between technical/scientific aspects of the modality and clinical application, this book includes over 100 super high-quality radiographic images and 100 additional graphics and tables.

Download or read book Intravoxel Incoherent Motion IVIM MRI written by Denis Le Bihan and published by CRC Press. This book was released on 2018-11-05 with total page 651 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intravoxel incoherent motion (IVIM) refers to translational movements which within a given voxel and during the measurement time present a distribution of speeds in orientation and/or amplitude. The concept was introduced in 1986 together with the foundation of diffusion MRI because it had been realized that flow of blood in capillaries (perfusion) would mimic a diffusion process and impact diffusion MRI measurements. IVIM-based perfusion MRI, which does not require injection of any tracer or contrast agent, has been first investigated in the brain, but is now experiencing a remarkable revival for applications throughout the body, especially for oncologic applications, from diagnosis to treatment monitoring. This book addresses a number of highly topical aspects of the field from leading authorities, introducing the concepts behind IVIM MRI, outlining related methodological issues, and summarizing its current usage and potential for clinical applications. It also presents future research directions, both in terms of methodological development and clinical application fields, extending to new, non-perfusion applications of IVIM MRI, such as virtual MR elastography.

Download or read book Brain Network Analysis written by Moo K. Chung and published by Cambridge University Press. This book was released on 2019-06-27 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: This coherent mathematical and statistical approach aimed at graduate students incorporates regression and topology as well as graph theory.

Download or read book Processing and Analysis of Phase and Magnitude MRI Data for Quantitative Cerebral Perfusion Imaging written by Melanie S. Kotys and published by . This book was released on 2004 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pattern Recognition and Signal Analysis in Medical Imaging written by Anke Meyer-Bäse and published by Academic Press. This book was released on 2004 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essential tool for students and professionals that compiles and explains proven and cutting-edge methods in pattern recognition for medical imaging.

Download or read book MRI from Picture to Proton written by Donald W. McRobbie and published by Cambridge University Press. This book was released on 2017-04-13 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: MR is a powerful modality. At its most advanced, it can be used not just to image anatomy and pathology, but to investigate organ function, to probe in vivo chemistry, and even to visualise the brain thinking. However, clinicians, technologists and scientists struggle with the study of the subject. The result is sometimes an obscurity of understanding, or a dilution of scientific truth, resulting in misconceptions. This is why MRI from Picture to Proton has achieved its reputation for practical clarity. MR is introduced as a tool, with coverage starting from the images, equipment and scanning protocols and traced back towards the underlying physics theory. With new content on quantitative MRI, MR safety, multi-band excitation, Dixon imaging, MR elastography and advanced pulse sequences, and with additional supportive materials available on the book's website, this new edition is completely revised and updated to reflect the best use of modern MR technology.

Download or read book Combined Spin and Gradient echo Perfusion MRI written by Heiko Hans Schmiedeskamp and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic susceptibility-contrast perfusion-weighted imaging (DSC PWI) is a magnetic resonance imaging (MRI) technique that measures the delivery of arterial blood to the tissue capillary bed using a contrast agent. DSC PWI can reveal important information in stroke patients by assessing hypoperfused brain tissue, while in tumor patients it is used to evaluate the tumor vasculature. For clinical applications, DSC PWI relies on both accurate and rapid image formation. Gradient-echo echo-planar imaging (EPI) is the most commonly used MRI pulse sequence for DSC PWI, mainly due to its fast image acquisition capability, a relatively high contrast-to-noise ratio, and its availability on most clinical MRI systems. However, quantification of perfusion parameters with gradient-echo EPI remains challenging. Gradient-echo EPI is most sensitive to larger vessels, including arteries and veins. These measurements do not provide specific information about true perfusion within the microvasculature, the site of oxygen and nutrient extraction to brain tissue. To acquire perfusion measurements that are more confined to the microvasculature, spin-echo EPI acquisition techniques have been proposed. Spin-echo EPI is most sensitive to smaller vessels, providing a clear advantage over gradient-echo EPI. Unfortunately, spin-echo EPI suffers from lower sensitivity to the contrast agent passage, and the determination of arterial contrast agent concentrations required for quantitative perfusion MRI remains an unsolved problem when using spin-echo EPI data. In the first part of this dissertation, a combined approach for simultaneous spin- and gradient-echo (SAGE) perfusion MRI is presented. The proposed imaging technique combines the advantages of higher overall sensitivity to contrast agent passage of gradient-echo EPI with superior microvascular selectivity of spin-echo EPI, resulting in complementary perfusion information. The combined method enabled improved detection of abnormal brain perfusion compared to conventionally processed DSC PWI data, as illustrated in cases of stroke and brain tumors. Specifically, reduced sensitivity to larger blood vessels of spin-echo data generated from SAGE perfusion MRI measurements improved the visibility of hypoperfused tissue. In the second part, the gradient-echo and spin-echo signal contributions to the proposed SAGE perfusion MRI acquisition technique are analyzed in detail. The development of an optimized pair of MRI excitation and refocusing pulses enhanced the contrast-to-noise ratio of the spin-echo signal. Moreover, augmented perfusion parameter estimation improved the accuracy of both gradient-echo and spin-echo signals to reduce perfusion quantification errors. In the last part, implications of contrast agent leakage from the brain vasculature are discussed. Considerable contrast agent extravasation, caused by blood-brain barrier leakage commonly observed in brain tumors and subacute strokes, results in additional quantification errors of brain perfusion parameters. To mitigate these errors, pharmacokinetic modeling of contrast agent distribution was applied to SAGE perfusion MRI data. Intravascular contrast agent concentrations could then be separated from extravascular concentrations, resulting in leakage-corrected perfusion data. Moreover, the applied pharmacokinetic modeling approach facilitated the extraction of permeability parameters. The combined evaluation of perfusion and permeability parameters, derived from SAGE perfusion MRI data, showed potential utility in brain tumor imaging with the goal of improving the diagnostic value of perfusion MRI in the assessment of brain tumor progression.

Download or read book Introduction to Perfusion Quantification using Arterial Spin Labelling written by Michael Chappell and published by Oxford University Press. This book was released on 2018-01-18 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arterial Spin Labeling (ASL) is an increasingly popular tool to study the brain. What sets it apart from other neuroimaging methods is the combination of quantitative measurements of a physiologically well-defined process, namely perfusion, and a completely non-invasive acquisition methodology. Cerebral perfusion is a critical component to brain health, as it is the primary means to deliver nutrients to support brain function as well as clearing waste products. Hence it is a useful quantity to study in disease where changes in perfusion can indicate regions of the brain that are pathological. Likewise changes in perfusion can be indicative of greater demand for nutrients, such as might be required in response to an increase in neuronal activity. With the advent of a consensus by the ASL community on good practice and a recommendation on robust methods for ASL data collection, more and more researchers are now able to access and use ASL. Despite the technological advances, ASL remains a technique with a low signal to noise ratio. This makes the wise choice of the appropriate analysis methods more important. The aim of this primer is to equip someone new to the field of perfusion imaging and ASL with the knowledge not only to make good choices about ASL acquisition and analysis, but also to understand what choices they are making and why. Examples of analysis applied to real data are given throughout the text and instructions on how to reproduce the analyses are illustrated on the primer website. Written to provide a stand-alone introduction to perfusion qualification using ASL, this primer also works with other texts in the Oxford Neuroimaging Primers series to provide a comprehensive overview of the increasingly influential field of neuroimaging.

Download or read book Measuring Resting Cerebral Perfusion using Magnetic Resonance Imaging MRI written by James Duffin and published by Frontiers Media SA. This book was released on 2024-07-12 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: The acquisition of resting cerebral perfusion measures using magnetic resonance imaging (MRI) is one of the assessments of cerebrovascular health used to discern how well patients are coping with anatomical changes such as stenosis, and other factors impacting the supply of blood flow to the brain. Perfusion measures may be obtained using several MRI based techniques including arterial spin labeling (ASL) and dynamic contrast enhanced methods that rely on injected contrast agents such as gadolinium. Recently hypoxia-induced changes in deoxyhemoglobin have been used as a non-invasive contrast agent, measuring the resulting changes in blood oxygen dependent (BOLD) signals with MRI. With each approach, the means through which voxel-wise cerebral perfusion information is derived differs, leading to the development a variety of analysis methods in recent studies. This Research Topic is intended to attract manuscripts that advance the use of resting cerebral perfusion measures in clinical assessments of cerebrovascular health. In pursuit of this aim a better understanding of several aspects are needed.

Download or read book Comprehensive Biomedical Physics written by and published by Newnes. This book was released on 2014-07-25 with total page 4052 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Biomedical Physics, Ten Volume Set is a new reference work that provides the first point of entry to the literature for all scientists interested in biomedical physics. It is of particularly use for graduate and postgraduate students in the areas of medical biophysics. This Work is indispensable to all serious readers in this interdisciplinary area where physics is applied in medicine and biology. Written by leading scientists who have evaluated and summarized the most important methods, principles, technologies and data within the field, Comprehensive Biomedical Physics is a vital addition to the reference libraries of those working within the areas of medical imaging, radiation sources, detectors, biology, safety and therapy, physiology, and pharmacology as well as in the treatment of different clinical conditions and bioinformatics. This Work will be valuable to students working in all aspect of medical biophysics, including medical imaging and biomedical radiation science and therapy, physiology, pharmacology and treatment of clinical conditions and bioinformatics. The most comprehensive work on biomedical physics ever published Covers one of the fastest growing areas in the physical sciences, including interdisciplinary areas ranging from advanced nuclear physics and quantum mechanics through mathematics to molecular biology and medicine Contains 1800 illustrations, all in full color

Download or read book Tensors for Data Processing written by Yipeng Liu and published by Academic Press. This book was released on 2021-10-21 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tensors for Data Processing: Theory, Methods and Applications presents both classical and state-of-the-art methods on tensor computation for data processing, covering computation theories, processing methods, computing and engineering applications, with an emphasis on techniques for data processing. This reference is ideal for students, researchers and industry developers who want to understand and use tensor-based data processing theories and methods. As a higher-order generalization of a matrix, tensor-based processing can avoid multi-linear data structure loss that occurs in classical matrix-based data processing methods. This move from matrix to tensors is beneficial for many diverse application areas, including signal processing, computer science, acoustics, neuroscience, communication, medical engineering, seismology, psychometric, chemometrics, biometric, quantum physics and quantum chemistry. - Provides a complete reference on classical and state-of-the-art tensor-based methods for data processing - Includes a wide range of applications from different disciplines - Gives guidance for their application