Download or read book Design and Simulation of Coils for High Field Magnetic Resonance Imaging and Spectroscopy written by Joseph Vincent Rispoli and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The growing availability of high-field magnetic resonance (MR) scanners has reignited interest in the in vivo investigation of metabolics in the body. In particular, multinuclear MR spectroscopy (MRS) data reveal physiological details inaccessible to typical proton (1H) scans. Carbon-13 (13C) MRS studies draw considerable appeal owing to the enhanced chemical shift range of metabolites that may be interrogated to elucidate disease metabolism and progression. To achieve the theoretical signal-to-noise (SNR) gains at high B0 fields, however, J-coupling from 1H-13C chemical bonds must be mitigated by transmitting radiofrequency (RF) proton-decoupling pulses. This irradiated RF power is substantial and intensifies with increased decoupling bandwidth as well as B0 field strength. The preferred 13C MRS experiment, applying broadband proton decoupling, thus presents considerable challenges at 7 T. Localized tissue heating is a paramount concern for all high-field studies, with strict Specific Absorption Rate (SAR) limits in place to ensure patient safety. Transmit coils must operate within these power guidelines without sacrificing image and spectral quality. Consequently, RF coils transmitting proton-decoupling pulses must be expressly designed for power efficiency as well as B1 field homogeneity. This dissertation presents innovations in high-field RF coil development that collectively improved the homogeneity, efficiency, and safety of high field 13C MRS. A review of electromagnetic (EM) theory guided a full-wave modeling study of coplanar shielding geometries to delineate design parameters for coil transmit efficiency. Next, a novel RF coil technique for achieving B1 homogeneity, dubbed forced current excitation (FCE), was examined and a coplanar-shielded FCE coil was implemented for proton decoupling of the breast at 7 T. To perform a series of simulation studies gauging SAR in the prone breast, software was developed to fuse a suite of anatomically-derived heterogeneous breast phantoms, spanning the standard four tissue density classifications, with existing whole-body voxel models. The effects of tissue density on SAR were presented and guidance for simulating the worst-case scenario was outlined. Finally, for improving capabilities of multinuclear coils during proton coil transmit, a high-power trap circuit was designed and tested, ultimately enabling isolation of 13C coil elements during broadband proton decoupling pulses. Together, this work advanced the hardware capabilities of high-field multinuclear spectroscopy with immediate applicability for performing broadband proton-decoupled 13C MRS in the breast at 7 T. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/155400

Download or read book Magnetic Resonance Technology written by Andrew G Webb and published by Royal Society of Chemistry. This book was released on 2016-04-27 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic resonance systems are used in almost every academic and industrial chemistry, physics and biochemistry department, as well as being one of the most important imaging modalities in clinical radiology. The design of such systems has become increasingly sophisticated over the years. Static magnetic fields increase continuously, large-scale arrays of receive elements are now ubiquitous in clinical MRI, cryogenic technology has become commonplace in high resolution NMR and is expanding rapidly in preclinical MRI, specialized high strength magnetic field gradients have been designed for studying the human connectome, and the commercial advent of ultra-high field human imaging has required new types of RF coils and static shim coils together with extensive electromagnetic simulations to ensure patient safety. This book covers the hardware and engineering that constitutes a magnetic resonance system, whether that be a high-resolution liquid or solid state system for NMR spectroscopy, a preclinical system for imaging animals or a clinical system used for human imaging. Written by a team of experts in the field, this book provides a comprehensive and instructional look at all aspects of current magnetic resonance technology, as well as outlooks for future developments.

Download or read book Design and Simulation of a Birdcage Coil Using CST Studio Suite for Application at 7T written by Bernat Palau Tomás and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: [ANGLÈS] This work describes the study of coil for Magnetic Resonance Imaging (MRI) application. Concretely, the principal objective is the design of a birdcage coil (RF coil) to use in a 7 Tesla scanner. More strength field has a better SNR and increased chemical shift effects, improving spectral fat suppression and spectroscopy. Moreover, a better SNR increases the spatial resolution or reduces the imaging time. For this reason, it is interesting research with high fields. The birdcage coil achieves circular polarization and generates a high homogeneous radio frequency magnetic field under many conditions. In this project is designed a Birdcage coil for a 7T to obtain images from small animals (like a mouse). It opens the door to design and construct a Birdcage coil for a 7T to obtain human brain images. In this project thesis, for obtain the design, a study is carried out firstly using the computer program BirdcageBuilder. Secondly, the results obtained with this simulator are introduced to the CST Microwave Studio, creating a 3D model and generating a simulation. In this step, finally the parameters are readjusted to obtain our desired Larmor frequency (298,2MHz) for a correct operation in 7T. These simulations demonstrate the theoretical results from our design and it shows the designed antenna behaviour.

Download or read book Ultra High Field Magnetic Resonance Imaging written by Pierre-Marie Robitaille and published by Springer Science & Business Media. This book was released on 2007-12-31 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt: The foundation for understanding the function and dynamics of biological systems is not only knowledge of their structure, but the new methodologies and applications used to determine that structure. This volume in Biological Magnetic Resonance emphasizes the methods that involve Ultra High Field Magnetic Resonance Imaging. It will interest researchers working in the field of imaging.

Download or read book RF Coils for MRI written by J. Thomas Vaughan and published by John Wiley & Sons. This book was released on 2012-12-19 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: The content of this volume has been added to eMagRes (formerly Encyclopedia of Magnetic Resonance) - the ultimate online resource for NMR and MRI. To date there is no single reference aimed at teaching the art of applications guided coil design for use in MRI. This RF Coils for MRI handbook is intended to become this reference. Heretofore, much of the know-how of RF coil design is bottled up in various industry and academic laboratories around the world. Some of this information on coil technologies and applications techniques has been disseminated through the literature, while more of this knowledge has been withheld for competitive or proprietary advantage. Of the published works, the record of technology development is often incomplete and misleading, accurate referencing and attribution assignment being tantamount to admission of patent infringement in the commercial arena. Accordingly, the literature on RF coil design is fragmented and confusing. There are no texts and few courses offered to teach this material. Mastery of the art and science of RF coil design is perhaps best achieved through the learning that comes with a long career in the field at multiple places of employment...until now. RF Coils for MRI combines the lifetime understanding and expertise of many of the senior designers in the field into a single, practical training manual. It informs the engineer on part numbers and sources of component materials, equipment, engineering services and consulting to enable anyone with electronics bench experience to build, test and interface a coil. The handbook teaches the MR system user how to safely and successfully implement the coil for its intended application. The comprehensive articles also include information required by the scientist or physician to predict respective experiment or clinical performance of a coil for a variety of common applications. It is expected that RF Coils for MRI becomes an important resource for engineers, technicians, scientists, and physicians wanting to safely and successfully buy or build and use MR coils in the clinic or laboratory. Similarly, this guidebook provides teaching material for students, fellows and residents wanting to better understand the theory and operation of RF coils. Many of the articles have been written by the pioneers and developers of coils, arrays and probes, so this is all first hand information! The handbook serves as an expository guide for hands-on radiologists, radiographers, physicians, engineers, medical physicists, technologists, and for anyone with interests in building or selecting and using RF coils to achieve best clinical or experimental results. About EMR Handbooks / eMagRes Handbooks The Encyclopedia of Magnetic Resonance (up to 2012) and eMagRes (from 2013 onward) publish a wide range of online articles on all aspects of magnetic resonance in physics, chemistry, biology and medicine. The existence of this large number of articles, written by experts in various fields, is enabling the publication of a series of EMR Handbooks / eMagRes Handbooks on specific areas of NMR and MRI. The chapters of each of these handbooks will comprise a carefully chosen selection of articles from eMagRes. In consultation with the eMagRes Editorial Board, the EMR Handbooks / eMagRes Handbooks are coherently planned in advance by specially-selected Editors, and new articles are written (together with updates of some already existing articles) to give appropriate complete coverage. The handbooks are intended to be of value and interest to research students, postdoctoral fellows and other researchers learning about the scientific area in question and undertaking relevant experiments, whether in academia or industry. Have the content of this Handbook and the complete content of eMagRes at your fingertips! Visit: www.wileyonlinelibrary.com/ref/eMagRes View other eMagRes publications here

Download or read book A General Purpose Computational Approach to the Design of Gradient Coils for Arbitrary Geometries written by and published by . This book was released on 2004 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: This research concentrates on two major engineering areas associated with biomedical instrumentation that have recently gained significant academic and industrial interest: the gradient coil design for Magnetic Resonance Imaging (MRI) and the high frequency full-wave field simulations with the Method of Moments (MoM). A new computational approach to the design of gradient coils for magnetic resonance imaging is introduced. The theoretical formulation involves a constrained cost function between the desired field in a particular region of interest in space and the current-carrying coil plane. Based on Biot-Savart's integral equation, an appropriate weight function is introduced in conjunction with linear approximation functions. This permits the transformation of the problem formulation into a linear matrix equation whose solution yields discrete current elements in terms of magnitude and direction within a specified coil plane. These current elements can be synthesized into practical wire configuration by suitably combining the individual wire loops. Numerical predictions and measurements underscore the success of this approach in terms of achieving a highly linear field while maintaining low parasitic fields, low inductance and a sufficient degree of shielding. Experimental results confirm the field predictions of the computational approach. Extending the numerical modeling efforts to dynamic phenomena, a novel MoM formulation permits the computation of electromagnetic fields in conductive surfaces and in three-dimensional biological bodies. The excitation can be provided with current loops, voltage sources, or an incident electromagnetic wave. This method enables us to solve a broad spectrum of problems arising in MRI: full-wave RF coil simulations, eddy currents predictions in the magnet bore, and induced currents in the biological body. Surfaces are represented as triangles and the three-dimensional bodies are subdivided into tetrahedra. This numerical discretization methodology makes the approach very flexible to handle a wide range of practical coil geometries. Specifically, in this thesis the MoM is employed to study the effect of switching gradient coils in the presence of a biological load.

Download or read book Nmr Probeheads For Biophysical And Biomedical Experiments Theoretical Principles And Practical Guidelines 2nd Edition written by Joel Mispelter and published by World Scientific Publishing Company. This book was released on 2015-05-27 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt: NMR Probeheads for Biophysical and Biomedical Experiments 2nd Edition is essential reading for anyone in the field of NMR or MRI, from students to medical or biological scientists performing experiments under certain physical and/or geometrical conditions, unattainable by conventional or available probes. The material guides the reader through the most basic and comprehensive stages in accomplishing a correct probe design, from a very basic oscillating circuit to much more elaborate designs.This new edition has been revised and updated to include a chapter dedicated to RF components, which are commonly used for probes realization and their frequency-dependent characteristics. Another completely revised chapter concerns the multiple coil systems and discusses arrays coils, different decoupling methods, and some principles for interfacing coils with low-noise preamplifiers. The principles of linear circuit analysis are presented in a dedicated chapter. Last but not least, accompanying files containing updated software for probe design have been made available from the publisher's website.

Download or read book Ultra high Field Magnetic Resonance Imaging Mri Instrumentation And Clinical Implementation written by Shaileshkumar B. Raval, Ph.D. and published by Index of Sciences Ltd. This book was released on 2021-04-06 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic Resonance Imaging“Magnetic Resonance Imaging” (MRI) is the most widely clinically used diagnostic tool for soft tissue imaging. This advanced technology and its applications are under continuous research and development, ranging from lower fields to ultra-high fields to the highest possible fields for preclinical (animal) and human imaging. Formerly known as Nuclear Magnetic Resonance Imaging (NMR), with the rising demands of clinical diagnosis requirements, it is under constant development and innovation in hospitals for populations around the world because of constant desire to go to higher fields that lead to unique research and clinical applications that aren’t achievable with other commercially and or research technologies. The basics of MRIThe human body is rich in hydrogen, when a human body is subjected to a large magnetic field, many of the free hydrogen nuclei align themselves with the direction of the magnetic field. MRI works on the principle of the directional magnetic field associated with charged particles in motion. MRI is also known as nuclear magnetic resonance imaging, a technique used to create images of parts of the human body based on the resonance of nuclei in motion under the effect of a magnetic field. Overview of the bookThis book’s lucid style makes it an easy read. It is written in a simple and comprehensible way, making it easy to followand readfor a large audience ranging from students to researchers. The areas covered include an overview of the theories and practical aspects of High-Field MRIwith each chapter Introduction, Challenges, Objectives, Methods(Materials), Results, Discussion, FutureWworks,including basic concepts, along with research-oriented and clinical concepts, technologies that are researched and developed, and implemented clinically, and published nationally and internationally recognized conferences, and publications with global awards recognition from ISMRM, TTS, and many other academic and industry organizationsthat are recognized worldwide. In this book, unexplored research theories are described along with a list of products, project developments, and completion of major and unattempted theories, which are considered to be challenging in high-field MRI. These unexplored research theories are further delved into to emerge with practical and translational products, as described in various chapters. These products are deemed to be of potential research and clinical use if implemented in clinical and hospital settings, to help thus could the patients as well as healthy populations to improve the standard of their lives. Advances in extremities and musculoskeletal imaging in patients undergoing transplants, including first-ever(never been implemented)technologies such as Ultra high field upper extremity RF coils, research publications, and intellectual properties have been explored in detail. Another major advancement discussed in this book is the Whole-body MRI RF high density transmit coil and receiver array designs(first evevr application of antenna design), published in national and international journals as intellectual properties. Various other aspects of these 4intellectual properties have been discussed such as instrumentation developed, design procedures, Electromagnetic Simulations (simulated versions), Novel whole head(Brain) MRI RF array, Innovative Visualization Techniques, Neuro and vascular flow imaging, Segmentation methods. Regenerative Imaging, Pre and post-operative (surgical) imaging, clinical implementations, pulse sequence developments and optimizations, imaging resultswith 3D volume Texture and Visualizations, also peer research and references from around the world, plus future works, and more have been entailed. This is a rather different book in terms of depth and detail in which the subject is dealt with in this book. The data is well represented with tables, equations, and nearly three hundred figures. Combining technologies, research, and clinical applications of innovations in the field of MRI, it is one of a kind and a treat for curious minds. The content is mainly focused on whole head imaging, whole-body imaging, and extremity imaging, describing their clinical applications and their implementation for high risk and high demand patient populations, healthy populations for enhanced human anatomical, biological, functional and physiological performances in a detailed manner. The research has been utilized by peers in their studies, research, publications, and learning as part of the research and clinical developments, and implementations. This book presents the author’s original research works and their applications in the real world to offer advanced innovations to the healthcare sector and improve quality and standard of life for the masses around the world and beyond as future goals as there are many aviations,Biomedical Applications and projects are in demand. The author’s research works have been publishedand awarded in various nationalllyand internationallyrecognized journals and presented in numerous conferences as well. The chapters of this book are each one of the many research publications by the author

Download or read book Brain and Human Body Modeling written by Sergey Makarov and published by Springer Nature. This book was released on 2019-08-27 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book describes modern applications of computational human modeling with specific emphasis in the areas of neurology and neuroelectromagnetics, depression and cancer treatments, radio-frequency studies and wireless communications. Special consideration is also given to the use of human modeling to the computational assessment of relevant regulatory and safety requirements. Readers working on applications that may expose human subjects to electromagnetic radiation will benefit from this book’s coverage of the latest developments in computational modelling and human phantom development to assess a given technology’s safety and efficacy in a timely manner. Describes construction and application of computational human models including anatomically detailed and subject specific models; Explains new practices in computational human modeling for neuroelectromagnetics, electromagnetic safety, and exposure evaluations; Includes a survey of modern applications for which computational human models are critical; Describes cellular-level interactions between the human body and electromagnetic fields.

Download or read book Nuclear Magnetic Resonance written by Navin Khaneja and published by . This book was released on 2020-04-08 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical and Analytical Methods in Electromagnetics written by Hristos T. Anastassiu and published by MDPI. This book was released on 2021-03-19 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Like all branches of physics and engineering, electromagnetics relies on mathematical methods for modeling, simulation, and design procedures in all of its aspects (radiation, propagation, scattering, imaging, etc.). Originally, rigorous analytical techniques were the only machinery available to produce any useful results. In the 1960s and 1970s, emphasis was placed on asymptotic techniques, which produced approximations of the fields for very high frequencies when closed-form solutions were not feasible. Later, when computers demonstrated explosive progress, numerical techniques were utilized to develop approximate results of controllable accuracy for arbitrary geometries. In this Special Issue, the most recent advances in the aforementioned approaches are presented to illustrate the state-of-the-art mathematical techniques in electromagnetics.

Download or read book Electromagnetics in Magnetic Resonance Imaging written by Christopher M. Collins and published by Morgan & Claypool Publishers. This book was released on 2016-03-01 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past few decades, Magnetic Resonance Imaging (MRI) has become an indispensable tool in modern medicine, with MRI systems now available at every major hospital in the developed world. But for all its utility and prevalence, it is much less commonly understood and less readily explained than other common medical imaging techniques. Unlike optical, ultrasonic, X-ray (including CT), and nuclear medicine-based imaging, MRI does not rely primarily on simple transmission and/or reflection of energy, and the highest achievable resolution in MRI is orders of magnitude smaller that the smallest wavelength involved. In this book, MRI will be explained with emphasis on the magnetic fields required, their generation, their concomitant electric fields, the various interactions of all these fields with the subject being imaged, and the implications of these interactions to image quality and patient safety. Classical electromagnetics will be used to describe aspects from the fundamental phenomenon of nuclear precession through signal detection and MRI safety. Simple explanations and Illustrations combined with pertinent equations are designed to help the reader rapidly gain a fundamental understanding and an appreciation of this technology as it is used today, as well as ongoing advances that will increase its value in the future. Numerous references are included to facilitate further study with an emphasis on areas most directly related to electromagnetics.

Download or read book Radio Frequency Coils for Ultra high Field Magnetic Resonance Imaging written by Daniel Lee and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radio Frequency Coils for Ultra high Field Magnetic Resonance Imaging written by Shajan Gunamony and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Magnetic Resonance Imaging written by Robert W. Brown and published by John Wiley & Sons. This book was released on 2014-06-23 with total page 976 pages. Available in PDF, EPUB and Kindle. Book excerpt: New edition explores contemporary MRI principles and practices Thoroughly revised, updated and expanded, the second edition of Magnetic Resonance Imaging: Physical Principles and Sequence Design remains the preeminent text in its field. Using consistent nomenclature and mathematical notations throughout all the chapters, this new edition carefully explains the physical principles of magnetic resonance imaging design and implementation. In addition, detailed figures and MR images enable readers to better grasp core concepts, methods, and applications. Magnetic Resonance Imaging, Second Edition begins with an introduction to fundamental principles, with coverage of magnetization, relaxation, quantum mechanics, signal detection and acquisition, Fourier imaging, image reconstruction, contrast, signal, and noise. The second part of the text explores MRI methods and applications, including fast imaging, water-fat separation, steady state gradient echo imaging, echo planar imaging, diffusion-weighted imaging, and induced magnetism. Lastly, the text discusses important hardware issues and parallel imaging. Readers familiar with the first edition will find much new material, including: New chapter dedicated to parallel imaging New sections examining off-resonance excitation principles, contrast optimization in fast steady-state incoherent imaging, and efficient lower-dimension analogues for discrete Fourier transforms in echo planar imaging applications Enhanced sections pertaining to Fourier transforms, filter effects on image resolution, and Bloch equation solutions when both rf pulse and slice select gradient fields are present Valuable improvements throughout with respect to equations, formulas, and text New and updated problems to test further the readers' grasp of core concepts Three appendices at the end of the text offer review material for basic electromagnetism and statistics as well as a list of acquisition parameters for the images in the book. Acclaimed by both students and instructors, the second edition of Magnetic Resonance Imaging offers the most comprehensive and approachable introduction to the physics and the applications of magnetic resonance imaging.

Download or read book Ultra High Field Neuro MRI written by Karin Markenroth Bloch and published by Elsevier. This book was released on 2023-08-21 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultra-High Field Neuro MRI is a comprehensive reference and educational resource on the current state of neuroimaging at ultra-high field (UHF), with an emphasis on 7T. Sections cover the MR physics aspects of UHF, including the technical challenges and practical solutions that have enabled the rapid growth of 7T MRI. Individual chapters are dedicated to the different techniques that most strongly benefit from UHF, as well as chapters with a focus on different application areas in anatomical, functional and metabolic imaging. Finally, several chapters highlight the neurological and psychiatric applications for which 7T has shown benefits. The book is aimed at scientists who develop MR technologies and support clinical and neuroscience research, as well as users who want to benefit from UHF neuro MR techniques in their work. It also provides a comprehensive introduction to the field. Presents the opportunities and technical challenges presented by MRI at ultra-high field Describes advanced ultra-high field neuro MR techniques for clinical and neuroscience applications Enables the reader to critically assess the specific UHF advantages over currently available techniques at clinical field strengths

Download or read book Design of Optimized Gradient Coils for Magnetic Resonance Imaging written by Yoseph Shiferaw and published by . This book was released on 1990 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: