Catherine Westbrook - Handbook of MRI Technique

1 Cover

2 Title Page

3 Copyright Page

4 Contributors

5 Preface

6 Acknowledgements

7 About the Companion Website

8 1 How to Use This Book INTRODUCTION COMMON INDICATIONS BASIC ANATOMY EQUIPMENT PATIENT POSITIONING SLICE PRESCRIPTION SUGGESTED PROTOCOL PROTOCOL OPTIMIZATION PATIENT CONSIDERATIONS CONTRAST USAGE SUMMARY TERMS AND ABBREVIATIONS USED IN PART 2 CONCLUSION

9 Part 1: Theoretical and Practical Concepts 2 Protocol Parameters and Trade‐offs INTRODUCTION SIGNAL‐TO‐NOISE RATIO (SNR) CONTRAST‐TO‐NOISE RATIO (CNR) SPATIAL RESOLUTION SCAN TIME DECISION STRATEGIES CONCLUSION 3 Pulse Sequences INTRODUCTION CONVENTIONAL SPIN ECHO (CSE) FAST SPIN ECHO OR TURBO SPIN ECHO (FSE/TSE) INVERSION RECOVERY (IR/FSE/TSE‐IR) REWOUND GRADIENT ECHO BALANCED GRE SPOILED GRE REVERSE ECHO GRE ECHO PLANAR IMAGING (EPI) CONCLUSION 4 Flow Phenomena and Artefacts FLOW PHENOMENAINTRODUCTION TIME OF FLIGHT (TOF) ENTRY SLICE PHENOMENON INTRA‐VOXEL DEPHASING FLOW ARTEFACT REMEDIES ARTEFACTSINTRODUCTION PHASE MISMAPPING ALIASING CHEMICAL SHIFT OUT‐OF‐PHASE SIGNAL CANCELLATION TRUNCATION MAGNETIC SUSCEPTIBILITY MAGIC ANGLE CONCLUSION 5 Gating and Respiratory Compensation Techniques INTRODUCTION CARDIAC GATING (ECG/EKG GATING) PERIPHERAL GATING (PE GATING) CINÉ IMAGING IMAGING PLANES RESPIRATORY COMPENSATION (RC) CONCLUSION 6 Patient Care and Safety INTRODUCTION PATIENT SCREENING SAFETY ZONES SAFETY CONCERNS DURING THE EXAMINATION PATIENT COUNSELLING PATIENT IMMOBILIZATION PATIENT AFTER‐CARE CONCLUSION 7 Contrast Agents INTRODUCTION GD‐BASED POSITIVE CONTRAST AGENTS NEGATIVE CONTRAST AGENTS PATIENT CONSIDERATIONS CONCLUSION

10 Part 2: Examination Areas 8 Head and Neck BRAIN TEMPORAL LOBES INTERNAL AUDITORY MEATUS AND POSTERIOR FOSSA PITUITARY FOSSA ORBITS PARANASAL SINUSES PHARYNX LARYNX THYROID AND PARATHYROID GLANDS SALIVARY GLANDS TEMPOROMANDIBULAR JOINTS VASCULAR IMAGING HEAD AND NECK IMAGING – KEY POINTS 9 Spine CERVICAL SPINE THORACIC SPINE LUMBAR SPINE WHOLE SPINE IMAGING SPINE IMAGING – KEY POINTS 10 Chest LUNGS AND MEDIASTINUM HEART AND GREAT VESSELS THYMUS BREAST AXILLA BRACHIAL PLEXUS CHEST IMAGING – KEY POINTS 11 Abdomen LIVER AND BILIARY SYSTEM KIDNEYS AND ADRENAL GLANDS PANCREAS BOWEL VASCULAR IMAGING ABDOMINAL IMAGING – KEY POINTS 12 Pelvis PROSTATE RECTUM AND TESTES UTERUS AND CERVIX PELVIC IMAGING – KEY POINTS 13 Upper Limb SHOULDER HUMERUS ELBOW FOREARM WRIST AND HAND UPPER LIMB IMAGING – KEY POINTS 14 Lower Limb HIPS FEMUR KNEE TIBIA AND FIBULA ANKLE FOOT VASCULAR IMAGING LOWER LIMB IMAGING – KEY POINTS 15 Paediatric Imaging INTRODUCTION CREATING THE RIGHT ENVIRONMENT SEDATION AND ANAESTHESIA THE MRI EXAMINATION CONCLUSION PAEDIATRIC IMAGING – KEY POINTS

11 Index

12 End User License Agreement

1 Chapter 1 Table 1.1 Abbreviations used in this book. Table 1.2 Summary of slice prescription criteria.

2 Chapter 2 Table 2.1 Summary of parameters. Table 2.2 Parameters and their trade‐offs.

3 Chapter 3 Table 3.1 Comparison of vendor acronyms.Table 3.2 Summary of contrast characteristics of pathology and normal anato...

4 Chapter 4Table 4.1 Artefacts and their remedies.

5 Chapter 6Table 6.1 Examples of acoustic noise (approximate loudness in dB).

1 Chapter 1 Figure 1.1 Correct placement of a flat surface receive coil. Figure 1.2 Positioning of the alignment lights.

2 Chapter 3 Figure 3.1 Conventional spin echo pulse sequence diagram with two echoes. ... Figure 3.2 Fast or turbo spin echo pulse sequence diagram.Figure 3.3 Inversion recovery pulse sequence diagram.Figure 3.4 Rewound gradient echo pulse sequence diagram.Figure 3.5 Spoiled gradient echo pulse sequence diagram.Figure 3.6 Reverse echo gradient echo pulse sequence diagram.Figure 3.7 Gradient echo – EPI pulse sequence diagram.

3 Chapter 4Figure 4.1 Time of flight flow phenomenon.Figure 4.2 Intra‐voxel dephasing.Figure 4.3 The periodicity of fat and water.

4 Chapter 5Figure 5.1 Correct placement of gating leads.Figure 5.2 A normal ECG trace and correct placement of the triggering level....Figure 5.3 The ECG trace including safeguarding windows.Figure 5.4 Data acquisition in ciné imaging. Four slice locations at four ph...Figure 5.5 Correct positioning of respiratory bellows to catch abdominal and...

5 Chapter 6Figure 6.1 MRI safety zones as recommended by the ACR Guidance Document on M...

6 Chapter 7Figure 7.1 Tumbling of water molecules. Top left (time 1), top right (time 2...

7 Chapter 8Figure 8.1 Transverse aspect of the brain showing inferior structures.Figure 8.2 Oblique aspect of the brain showing inferior structures.Figure 8.3 Sagittal localizer of the brain showing the ACPC axis. (Source: S...Figure 8.4 Sagittal localizer showing slice prescription and angulation for ...Figure 8.5 Sagittal localizer showing slice prescription and angulation for ...Figure 8.6 Coronal FSE/TSE T2‐weighted image with radial k ‐space demonstrati...Figure 8.7 Axial IR‐T1‐weighted image of the brain.Figure 8.8 Axial FLAIR T2‐weighted image with radial k ‐space demonstrating h...Figure 8.9 DWI of the brain with a b value of 1000 mm 2/s. The high signal in...Figure 8.10 Tractography demonstrating tract orientation.Figure 8.11 Frequency and amplitude of common metabolites in the brain, meas...Figure 8.12 Image showing VOI in an MRS of the brain.Figure 8.13 The temporal lobe and its relationships.Figure 8.14 Sagittal localizer showing slice prescription and angulation for...Figure 8.15 Sagittal localizer showing slice prescription and angulation for...Figure 8.16 Coronal FSE/TSE‐IR T2‐weighted image of the brain with TI select...Figure 8.17 Coronal FSE/TSE‐IR T2‐weighted image video inverted to better de...Figure 8.18 Coronal localizer showing slice prescription for axial imaging o...Figure 8.19 Sagittal localizer showing slice prescription for coronal imagin...Figure 8.20 Axial FSE/TSE T2‐weighted high spatial resolution image demonstr...Figure 8.21 Axial FSE/TSE T2‐weighted high spatial resolution image demonstr...Figure 8.22 The pituitary fossa and its relationships.Figure 8.23 Sagittal localizer showing slice prescription and angulation for...Figure 8.24 Sagittal localizer showing slice prescription and angulation for...Figure 8.25 Coronal FSE/TSE T1‐weighted image after contrast enhancement dem...Figure 8.26 The structures of the orbit in sagittal section.Figure 8.27 Inner structures of the eye.Figure 8.28 Sagittal localizer showing the correct orientation for axial/obl...Figure 8.29 Sagittal localizer showing slice prescription and angulation for...Figure 8.30 Sagittal localizer showing slice prescription and angulation for...Figure 8.31 Coronal STIR of the orbits demonstrating a venous malformation. ...Figure 8.32 Axial 3D FSE/TSE T2‐weighted image with parallel imaging demonst...Figure 8.33 Anterior view of the paranasal sinuses.Figure 8.34 Sagittal localizer showing slice prescription and angulation for...Figure 8.35 Sagittal localizer showing slice prescription and angulation for...Figure 8.36 Sagittal/oblique section through the mouth, larynx and pharynx....Figure 8.37 Sagittal localizer showing slice prescription and angulation for...Figure 8.38 Coronal localizer showing slice prescription for axial imaging o...Figure 8.39 Coronal localizer showing slice prescription for sagittal imagin...Figure 8.40 Coronal STIR with radial k ‐space demonstrating a nasopharyngeal ...Figure 8.41 Sagittal localizer showing slice prescription for axial imaging ...Figure 8.42 Sagittal localizer showing slice prescription and angulation for...Figure 8.43 Axial FSE/TSE T2‐weighted image with fat suppression (Dixon) dem...Figure 8.44 Coronal STIR MIP demonstrating lymphoma.Figure 8.45 Sagittal view of the thyroid gland and its relationships.Figure 8.46 Anterior view of the thyroid gland and its relationships.Figure 8.47 Coronal localizer showing slice prescription for axial imaging o...Figure 8.48 Axial FSE/TSE T1‐weighted image with fat suppression (Dixon) dem...Figure 8.49 Axial FSE/TSE T2 weighted image with fat suppression (Dixon) dem...Figure 8.50 Sagittal view of the TMJ and its relationships.Figure 8.51 Axial localizer showing slice prescription and angulation for sa...Figure 8.52 Contrast enhanced multi‐phase images of the brain.Figure 8.53 Phase contrast venogram of the brain.Figure 8.54 Coronal contrast‐enhanced MRA of the neck vessels.