Handbook of MRI Technique E-Book

Catherine Westbrook

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 450

Veröffentlichungsjahr: 2014

Beschreibung

Now entering its fourth edition, the market-leading Handbook of MRI Technique has been fully revised and updated to incorporate new technologies and developments essential to good practice. Written specifically for technologists and highly illustrated, it guides the uninitiated through scanning techniques and helps more experienced technologists to improve image quality.

The first part of the book considers the main aspects of theory that relate to scanning and also includes practical tips on gating, equipment use, patient care and safety, and information on contrast media. The second half provides step-by-step instruction for examining each anatomical area, beginning with a basic anatomy section followed by sections on indications, patient positioning, equipment, artefacts and tips on optimizing image quality.

• Written by an international team of technologists from the United States, United Kingdom and Europe
• Suitable for users for all types of MRI systems
• Now includes key points throughout for quick reference
• Companion website at www.wiley.com/go/westbrook/mritechnique with self-assessment and image flashcards

Handbook of MRI Technique continues to be the ideal support both for radiographers new to MRI and for regular users looking for information on alternative techniques and suggestions on protocol modifications.

Leseprobe

CONTENTS

Cover

Title page

Copyright page

Preface

Acknowledgements

Contributors

1 How to use this book

Introduction

Basic anatomy

Common indications

Equipment

Patient positioning

Suggested protocol

Image optimization

Patient considerations

Contrast usage

Terms and abbreviations used in Part 2

Conclusion

Abbreviations

Part 1: Theoretical and practical concepts

2 Parameters and trade-offs

Introduction

Signal to noise ratio

Contrast to noise ratio

A note on tissue suppression techniques

Spatial resolution

Scan time

Decision strategies

Conclusion

3 Pulse sequences

Introduction

Spin echo

Fast spin echo or turbo spin echo

Inversion recovery (IR/IR-FSE)

Coherent gradient echo (T2*)

Balanced gradient echo (T2*)

Incoherent (spoiled) gradient echo (T1/PD)

Steady-state free precession (T2)

Echo planar imaging

Magnetic resonance angiography

Conclusion

4 Flow phenomena and artefacts

Flow phenomena

Introduction

Time of flight

Entry slice phenomenon

Intra-voxel dephasing

Flow artefact remedies

Artefacts

Introduction

Phase mismapping

Aliasing

Chemical shift

Chemical misregistration

Truncation

Magnetic susceptibility

Conclusion

5 Gating and respiratory compensation techniques

Introduction

Cardiac gating (ECG gating)

Lead placement

How to improve the trace

Cable safety

Peripheral gating (Pe gating)

Gating parameters

Cine imaging

Respiratory compensation (RC)

Conclusion

6 Patient care and safety

Introduction

Patient safety

Patient counselling

Patient immobilization

Patient after care

Conclusion

7 Contrast agents

Introduction

Positive contrast agents

Negative contrast agents

Conclusion

Part 2: Examination areas

8 Head and neck

Brain

Basic anatomy

(Figures 8.1 and 8.2)

Temporal lobes

Basic anatomy

(Figure 8.21)

Posterior fossa and internal auditory meatus

Pituitary fossa

Basic anatomy

(Figure 8.32)

Basic anatomy

(Figures 8.36 and 8.37)

Paranasal sinuses

Pharynx

Basic anatomy

(Figure 8.45)

Larynx

Basic anatomy

(Figure 8.45)

Thyroid and parathyroid glands

Basic anatomy

(Figures 8.52 and 8.53)

Salivary glands

Temporomandibular joints

Basic anatomy

(Figure 8.55)

Vascular imaging

9 Spine

Cervical spine

Basic anatomy

(Figures 9.1 and 9.2)

Thoracic spine

Lumbar spine

Whole spine imaging

10 Chest

Lungs and mediastinum

Basic anatomy

(Figure 10.1)

Heart and great vessels

Basic anatomy

(Figures 10.9 and 10.10)

Thymus

Breast

Basic anatomy

(Figure 10.23)

Axilla

Brachial plexus

11 Abdomen

Liver and biliary system

Basic anatomy

(Figure 11.1)

Kidneys and adrenal glands

Basic anatomy

(Figure 11.8)

Pancreas

Basic anatomy

(Figure 11.15)

Vascular imaging

12 Pelvis

Male pelvis

Basic anatomy

(Figure 12.1)

Female pelvis

Basic anatomy

(Figure 12.10)

Obstetrics

13 Upper limb

Shoulder

Basic anatomy

(Figure 13.1)

Humerus

Basic anatomy

(Figure 13.12)

Elbow

Basic anatomy

(Figures 13.13 and 13.14)

Forearm

Wrist and hand

Key points

14 Lower limb

Hips

Basic anatomy

(Figure 14.1)

Femur

Basic anatomy

(Figure 14.7)

Knee

Basic anatomy

(Figure 14.8)

Tibia and fibula

Basic anatomy

(Figure 14.19)

Ankle

Basic anatomy

(Figure 14.21)

Foot

Vascular imaging

Basic anatomy

(Figures 14.33 and 14.34)

Index

Access to companion website

End User License Agreement

List of Tables

Chapter 02

Table 2.1 Summary of parameters

Table 2.2 Parameters and their trade-offs

Chapter 03

Table 3.1 Comparison of manufacturer acronyms (see

How to use this book

for abbreviations)

Table 3.2 Summary of the contrast characteristics of pathology and normal anatomy

Chapter 04

Table 4.1 Artefacts and their remedies

Chapter 08

Table 8.1

Summary of parameters

Chapter 09

Table 9.1

Summary of parameters

Chapter 10

Table 10.1

Summary of parameters

Chapter 11

Table 11.1

Summary of parameters

Chapter 12

Table 12.1

Summary of parameters

Chapter 13

Table 13.1

Summary of parameters

Chapter 14

Table 14.1

Summary of parameters

List of Illustrations

Chapter 01

Figure 1.1 Correct placement of a flat surface coil in the bore of the magnet. The surface of the coil (shaded) area must be parallel to the Z axis to receive signal. The coil is therefore positioned so that transverse magnetization created in the X and Y axes is perpendicular to the coil.

Figure 1.2 Positioning of the alignment lights.

Chapter 05

Figure 5.1 The correct placement of gating leads.

Figure 5.2 A normal ECG Trace and the correct placement of the triggering threshold relative to the R wave.

Figure 5.3 Correct positioning of the respiratory bellows to ‘catch' both thoracic and abdominal respiration.

Chapter 08

Figure 8.1 Transverse aspect of the brain showing inferior structures.

Figure 8.2 Oblique aspect of the brain showing inferior structures.

Figure 8.3 Axial/oblique FSE T2-weighted image of the brain showing normal appearances.

Figure 8.4 Sagittal SE T1-weighted midline slice of the brain showing the axis of the anterior and posterior commissures.

Figure 8.5 Sagittal SE T1-weighted midline slice of the brain showing slice prescription boundaries and orientation for axial/oblique imaging.

Figure 8.6 Sagittal SE T1-weighted image showing slice prescription boundaries and orientation for coronal imaging.

Figure 8.7 Axial IR T1-weighted image using a TI of 700 ms.

Figure 8.8 Axial/oblique FLAIR image of the brain. Periventricular abnormalities will have a high signal intensity in contrast to the low signal of CSF which has been nulled using a long TI.

Figure 8.9 Axial/oblique incoherent (spoiled) GRE image of the brain.

Figure 8.10 SS-FSE T2-weighted image of the brain. The entire brain was scanned in 40 s.

Figure 8.11 SS-EPI image of the brain. The entire brain was scanned in 14 s.

Figure 8.12 DWI showing large area of high signal on right. High signal on a DWI can be the result of restricted diffusion or ‘T2 shine-through'.

Figure 8.13 Calculated ADC image showing restricted diffusion (acute stroke) as low signal. Small area of high signal in right posterior represents ‘T2 shine-through'.

Figure 8.14 T2-weighed FLAIR showing lesion.

Figure 8.15 Fractional anisotropy (FA) map showing anisotropic (ordered) diffusion in the white matter tracts.