In Vivo NMR Spectroscopy

Presents basic concepts, experimental methodology and data acquisition, and processing standards of in vivo NMR spectroscopy

This book covers, in detail, the technical and biophysical aspects of in vivo NMR techniques and includes novel developments in the field such as hyperpolarized NMR, dynamic 13C NMR, automated shimming, and parallel acquisitions. Most of the techniques are described from an educational point of view, yet it still retains the practical aspects appreciated by experimental NMR spectroscopists. In addition, each chapter concludes with a number of exercises designed to review, and often extend, the presented NMR principles and techniques.

The third edition of In Vivo NMR Spectroscopy: Principles and Techniques has been updated to include experimental detail on the developing area of hyperpolarization; a description of the semi-LASER sequence, which is now a method of choice; updated chemical shift data, including the addition of 31P data; a troubleshooting section on common problems related to shimming, water suppression, and quantification; recent developments in data acquisition and processing standards; and MatLab scripts on the accompanying website for helping readers calculate radiofrequency pulses.

    Provide an educational explanation and overview of in vivo NMR, while maintaining the practical aspects appreciated by experimental NMR spectroscopists
    Features more experimental methodology than the previous edition
    End-of-chapter exercises that help drive home the principles and techniques and offer a more in-depth exploration of quantitative MR equations
    Designed to be used in conjunction with a teaching course on the subject

In Vivo NMR Spectroscopy: Principles and Techniques, 3rd Edition is aimed at all those involved in fundamental and/or diagnostic in vivo NMR, ranging from people working in dedicated in vivo NMR institutes, to radiologists in hospitals, researchers in high-resolution NMR and MRI, and in areas such as neurology, physiology, chemistry, and medical biology

CONTENTS

1 Principles of NMR

1.1 Introduction

1.2 Classical magnetic moments

1.3 Nuclear magnetization

1.4 Nuclear induction

1.5 Rotating frame of reference

1.6 Transverse T2 and T2* relaxation

1.7 Bloch equations

1.8 Fourier transform NMR

1.9 Chemical shift

1.10 Digital NMR

1.10.1 Analog-to-digital conversion

1.10.2 Signal averaging

1.10.3 Digital Fourier transformation

1.10.4 Zero filling

1.10.5 Apodization

1.11 Quantum description of NMR

1.12 Scalar coupling

1.13 Chemical and magnetic equivalence

1.14 Exercises

References

2 In Vivo NMR Spectroscopy – Static Aspects

2.1 Introduction

2.2 Proton NMR Spectroscopy

2.2.1 Acetate (Ace)

2.2.2 N-Acetyl Aspartate (NAA)

2.2.3 N-Acetyl Aspartyl Glutamate (NAAG)

2.2.4 Adenosine Triphosphate (ATP)

2.2.5 Alanine (Ala)

2.2.6 g-Aminobutyric Acid (GABA)

2.2.7 Ascorbic Acid (Asc)

2.2.8. Aspartic Acid (Asp)

2.2.9 Branched-chain amino acids (isoleucine, leucine and valine)

2.2.10 Choline-Containing Compounds (tCho)

2.2.11 Creatine (Cr) and Phosphocreatine (PCr)

2.2.12 Ethanol

2.2.13 Ethanolamine (EA) and Phosphorylethanolamine (PE)

2.2.14 Glutamate (Glu)

2.2.15 Glutamine (Gln)

2.2.16 Glutathione (GSH)

2.2.17 Glycerol

2.2.18 Glycine

2.2.19 Glycogen

2.2.20 Histidine

2.2.21 Homocarnosine

2.2.22 b-Hydoxybutyrate (BHB)

2.2.23 2-Hydroxyglutarate (2HG)

2.2.24 Myo-Inositol (mI) and scyllo-Inositol (sI)

2.2.25 Lactate (Lac)

2.2.26 Macromolecules

2.2.27 Nicotinamide Adenine Dinucleotide (NAD+)

2.2.28 Phenylalanine

2.2.29 Pyruvate

2.2.30 Serine

2.2.31 Succinate

2.2.32 Taurine (Tau)

2.2.33 Threonine (Thr)

2.2.34 Tryptophan (Trp)

2.2.35 Tyrosine (Tyr)

2.2.36 Water

2.2.37 Non-cerebral metabolites

2.2.38 Carnitine and acetyl-carnitine

2.2.39 Carnosine

2.2.40 Citric Acid

2.2.41 Deoxymyoglobin (DMb)

2.2.42 Lipids

2.2.43 Spermine and polyamines

2.3 Phosphorus-31 NMR spectroscopy

2.3.1 Chemical shifts

2.3.2 Intracellular pH

2.4 Carbon-13 NMR spectroscopy

2.4.1 Chemical shifts

2.5 Sodium-23 NMR spectroscopy

2.6 Fluorine-19 NMR spectroscopy

2.7 In vivo NMR on other non-proton nuclei

2.8 Exercises

References

3 In Vivo NMR Spectroscopy – Dynamic Aspects

3.1 Introduction

3.2 Relaxation

3.2.1 General principles of dipolar relaxation

3.2.2 Nuclear Overhauser effect

3.2.3 Alternative relaxation mechanisms

3.2.4 Effects of T1 relaxation

3.2.5 Effects of T2 relaxation

3.2.6 Measurement of T1 and T2 relaxation

3.2.7 In vivo relaxation

3.3 Magnetization transfer

3.3.1 Principles of magnetization transfer

3.3.2 Magnetization transfer methods

3.3.3 Multiple exchange reactions

3.3.4 Magnetization transfer contrast (MTC)

3.3.5 Chemical exchange saturation transfer (CEST)

3.4 Diffusion

3.4.1 Principles of diffusion

3.4.2 Diffusion and NMR

3.4.3 Anisotropic diffusion

3.4.4 Restricted diffusion

3.5 Dynamic NMR of isotopically-enriched substrates

3.5.1 General principles and setup

3.5.2 Metabolic modeling

3.5.3 Thermally polarized dynamic 13C NMR spectroscopy

3.5.4 Hyperpolarized dynamic 13C NMR spectroscopy

3.5.5 Deuterium metabolic imaging

3.6 Exercises

References

4 Magnetic Resonance Imaging

4.1 Introduction

4.2 Magnetic field gradients

4.3 Slice selection

4.4 Frequency encoding

4.4.1 Principle

4.4.2 Echo formation

4.5 Phase encoding

4.6 Spatial frequency space

4.7 Fast MRI sequences

4.7.1 Reduced TR methods

4.7.2 Rapid k-space traversal

4.7.3 Parallel MRI

4.8 Contrast in MRI

4.8.1 T1 and T2 relaxation mapping

4.8.2 Magnetic field B0 mapping

4.8.3 Magnetic field B1 mapping

4.8.4 Alternative image contrast mechanisms

4.8.5 Functional MRI

4.9 Exercises

References

5 Radiofrequency Pulses

5.1 Introduction

5.2 Square RF pulses

5.3 Selective RF pulses

5.3.1 Fourier-transform-based RF pulses

5.3.2 RF pulse characteristics

5.3.3 Optimized RF pulses

5.3.4 Multi-frequency RF pulses

5.4 Composite RF pulses

5.5 Adiabatic RF pulses

5.5.1 Rotating frame of reference

5.5.2 Adiabatic condition

5.5.3 Modulation functions

5.5.4 AFP refocusing

5.5.5 Adiabatic plane rotation of arbitrary nutation angle

5.6 Multi-dimensional RF pulses

5.7 Spectral-spatial RF pulses

5.8 Exercises

References

6 Single Volume Localization and Water Suppression

6.1 Introduction

6.2 Single-volume localization

6.2.1 Image-selected in vivo spectroscopy (ISIS)

6.2.2 Chemical shift displacement

6.2.3 Coherence selection

6.2.4 Stimulated echo acquisition mode (STEAM)

6.2.5 Point resolved spectroscopy (PRESS)

6.2.6 Localization by adiabatic selective refocusing (LASER)

6.3 Water suppression

6.3.1 Binomial and related pulse sequences

6.3.2 Frequency selective excitation

6.3.3 Frequency selective refocusing

6.3.4 Relaxation based methods

6.3.5 Non-water-suppressed NMR spectroscopy

6.4 Exercises

References

7 Spectroscopic Imaging and Multivolume Localization

7.1 Introduction

7.2 Principles of MR spectroscopic imaging

7.3 K-space description of MRSI

7.4 Spatial resolution in MRSI

7.5 Temporal resolution in MRSI

7.5.1 Conventional methods

7.5.2 Methods based on fast MRI

7.5.3 Methods based on prior knowledge

7.6 Lipid suppression

7.6.1 Relaxation based methods

7.6.2 Inner volume selection (IVS) and volume pre-localization

7.6.3 Outer volume suppression (OVS)

7.7 MR spectroscopic image processing and display

7.8 Multi-volume localization

7.8.1 Hadamard localization

7.8.2 Sequential multi-volume localization

7.9 Exercises

References

8 Spectral Editing and 2D NMR

8.1 Introduction

8.2 Quantitative descriptions of NMR

8.2.1 Density matrix formalism

8.2.2 Classical vector model

8.2.3 Correlated vector model

8.2.4 Product operator formalism

8.3 Scalar evolution

8.4 J-difference editing

8.4.1 Principle

8.4.2 Practical considerations

8.4.3 GABA, 2HG and lactate

8.5 Multiple quantum coherence editing

8.6 Spectral editing alternatives

8.7 Heteronuclear spectral editing

8.7.1 Proton-observed, carbon-edited (POCE) MRS

8.7.2 Polarization transfer – INEPT and DEPT

8.8 Broadband decoupling

8.9 Sensitivity

8.10 Two-dimensional NMR spectroscopy

8.10.1 Correlation spectroscopy (COSY)

8.10.2 J-resolved spectroscopy

8.10.3 In vivo 2D NMR methods

8.11 Exercises

References

9. Spectral Quantification

9.1 Introduction

9.2 Data acquisition

9.3 Data pre-processing

9.3.1 Phased-array coil combination

9.3.2 Phasing and frequency alignment

9.3.3 Line shape correction

9.3.4 Removal of residual water

9.3.5 Baseline correction

9.4 Data quantification

9.4.1 Time- and frequency-domain parameters

9.4.2 Prior knowledge

9.4.3 Spectral fitting algorithms

9.4.4 Error estimation

9.5 Data calibration

9.5.1 Internal concentration reference

9.5.2 External concentration reference

9.5.3 Phantom replacement concentration reference

9.6 Exercises

References

10 Hardware

10.1 Introduction

10.2 Magnets

10.3 Magnetic field homogeneity

10.3.1 Origins of magnetic field inhomogeneity

10.3.2 Effects of magnetic field inhomogeneity

10.3.3 Principles of spherical harmonic shimming

10.3.4 Practical spherical harmonic shimming

10.3.5 Alternative shimming strategies

10.4 Magnetic field gradients

10.4.1 Eddy currents

10.4.2 Pre-emphasis

10.4.3 Active shielding

10.5 Radiofrequency (RF) coils

10.5.1 Electrical circuit analysis

10.5.2 RF coil performance

10.5.3 Spatial field properties

10.5.4 Principle of reciprocity

10.5.5 Parallel transmission

10.5.6 RF power and specific absorption rate (SAR)

10.5.7 Specialized RF coils

10.6 Complete MR system

10.6.1 RF transmission

10.6.2 Signal reception

10.6.3 Quadrature detection

10.6.4 Dynamic range

10.6.5 Gradient and shim systems

10.7 Exercises

References

Appendix

Index