Rad Tech's Guide to Computed Tomography - Euclid Seeram

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Résumé :

Foreword viii

Preface xi

Acknowledgments xiv

1 The Invention of the CT Scanner and the Nobel Prize 1

Computed Tomography: A Definition 2

Three Major Stages of CT Imaging 4

Invention of the CT Scanner: The Nobel Prize for Pioneers Godfrey Hounsfield and Alan Cormack 8

Evolution of CT Scanners Leading to Present- Day Multi- Slice CT Imaging 10

References 14

2 Essential Physics of CT 17

Introduction 17

Radiation Attenuation: Essential Physics Related to CT Imaging 18

Attenuation and Hounsfield Units 22

The CT Gray- Scale Image 24

References 25

3 Data Acquisition: Principles and Technology 27

What Is Data Acquisition? 28

Types of Data Acquisition 28

Major Technical Data Acquisition Components 31

Detectors: Types, Principles, and Technology 35

References 41

4 Image Reconstruction Principles 43

Image Reconstruction: A Definition 45

Image Reconstruction Algorithms 45

Artificial Intelligence and Its Subsets: Definitions 52

References 59

5 Multi- Slice CT: Principles and Instrumentation 62

What Is Multi- Slice CT (MSCT)? 63

MSCT System Components 65

Selectable Scan Parameters 71

Advantages of MSCT 73

References 74

6 Image Postprocessing 76

Scope of Image Processing 77

Windowing: Effect on Image Contrast and Image Brightness 79

Multiplanar Image Reformatting 82

Advanced Image Postprocessing Techniques 84

References 88

7 Image Quality 90

What Is Image Quality in Computed Tomography? 90

Spatial Resolution 91

Low- Contrast Resolution 93

Noise 95

Artifacts in a Nutshell 98

References 99

8 CT Radiation Dose Considerations 101

CT Dose Trends 101

The Basics of CT Dosimetry 102

Factors Affecting the Dose in CT 105

Dose Optimization 107

References 109

9 CT Quality Control for Technologists/ Radiographers 114

Quality Assurance/Quality Control: Definitions 115

Essential Steps in QC 116

Tolerance Limits/Acceptance Criteria 117

Equipment for QC Testing 118

Routine QC Tests for the CT Technologist 121

References 124

Index 125