Magnetic resonance imaging (MRI) is a rapidly developing field in basic applied science and clinical practice. Research efforts in this area have already been recognized with five Nobel prizes awarded to seven Nobel laureates in the past 70 years. Based on courses taught at The Johns Hopkins University, Magnetic Resonance Imaging: The Basics provides a solid introduction to this powerful technology.
The book begins with a general description of the phenomenon of magnetic resonance and a brief summary of Fourier transformations in two dimensions. It examines the fundamental principles of physics for nuclear magnetic resonance (NMR) signal formation and image construction and provides a detailed explanation of the mathematical formulation of MRI. Numerous image quantitative indices are discussed, including (among others) signal, noise, signal-to-noise, contrast, and resolution.
The second part of the book examines the hardware and electronics of an MRI scanner and the typical measurements and simulations of magnetic fields. It introduces NMR spectroscopy and spectral acquisition and imaging techniques employing various pulse sequences. The final section explores the advanced imaging technique of parallel imaging.
Structured so that each chapter builds on the knowledge gained in the previous one, the book is enriched by numerous worked examples and problem sets with selected solutions, giving readers a firm grasp of the foundations of MRI technology.
Fourier Transformations
Mathematical Representation of Images
Continuous Images
Delta Function
Separable Images
Linear Shift Invariant (LSI) Systems
Cascade Systems
Stability
Fourier Transformation and Inverse FT
Properties of Fourier Transformations
Frequency Response
Discrete Images and Systems
Separable Images
Linear Shift Invariant Systems
Frequency Response—Point Spread Sequence
Discrete Fourier Transform and Its Inverse
Properties of Discrete Fourier Transforms
Fundamentals of Magnetic Resonance Imaging
Quantum Mechanical Description of NMR: Energy Level Diagrams
Boltzmann Statistics
Pulsed and Continuous Wave NMR
Spin Quantum Numbers and Charge Densities
Angular Momentum and Precession
Overview of MR Instrumentation
The Classical View of NMR—A Macroscopic Approach
Rotating Frame and Laboratory Frame
RF Excitation and Detection
Molecular Spin Relaxation—Free Induction Decay
T1 and T2 Measurements
Relaxation Times in Biological Tissues
Molecular Environment and Relaxation
Biophysical Aspects of Relaxation Times
Spectral Density and Correlation Times
T1 and T2 Relaxation
Quadrupolar Moments
Fundamentals of Magnetic Resonance II: Imaging
Magnetic Field Gradients
Spin–Warp Imaging and Imaging Basics
Slice Selection
Multislice and Oblique Excitations
Frequency Encoding
Phase Encoding
Fourier Transformation and Image Reconstruction
Fundamentals of Magnetic Resonance III: The Formalism of k-Space
MRI Signal Formulation
k-Space Formalism and Trajectories
Concept of Pulse Sequences
Echo Planar Imaging
Pulse Sequences
T1, T2, and Proton Density-Weighted Images
Saturation Recovery, Spin–Echo, Inversion Recovery
Gradient–Echo Imaging: FLASH, SSFP, and STEAM
Bloch Equation Formulation and Simulations
Technical Limits and Safety
Introduction to Instrumentation
Magnets and Designs
Stability, Homogeneity, and Fringe Field
Gradient Coils
RF Coils
RF Decoupling
B Field Distributions and Simulations
Safety Issues
Tour of an MRI Facility
Hardware
Imaging
Generation of MRI Images
Safety
Signal, Noise, Resolution, and Image Contrast
Signal and Noise Sources in MRI
Signal to Noise Ratio
Contrast-to-Noise Ratio
Tissue Parameters and Image Dependence
Imaging Parameters and Image Dependence
Resolution
Spectroscopy and Spectroscopic Imaging
Introduction to NMR Spectroscopy
Fundamental Principles
Localized Spectroscopy
Imaging Equation and Spectroscopic Imaging
Advanced Imaging Techniques: Parallel Imaging
Introduction to Parallel Imaging
Parallel Imaging Fundamentals
Transmit Phased Arrays
Problem Sets
Multiple Choice Questions
Solutions to Selected Problems
Answers to Multiple Choice Questions
Glossary
Bibliography
Index
Biography
Christakis Constantinides, PhD joined the faculty of the Mechanical Engineering Department at the University of Cyprus in September 2005. He has also acted as a consultant to his start-up firm, Chi-Biomedical Ltd. ever since. His specific research interest focuses on the study of cardiac mechanical function, computational and tissue structure modeling and characterization, hardware design, and functional and cellular tracking methods using MRI. The goal of his research efforts is the complete characterization of the electromechanical function of the heart in small animals and humans, aiming to promote the understanding of mechanisms of human disease that is predominantly underlined by genetic causes.
"Overall this is excellent book and author has taken lot of time/effort to explain complex physiscs concepts. It will be of great use to all the radiology trainees who wish to learn more about MRI physiscs."
—Jagadish Malla, The Society of Radiologists in Training