The CT Handbook: Optimizing Protocols for Today's Feature-Rich Scanners
Author: Timothy P. SzczykutowiczISBN: 9780944838532
Published: May 2020 | 580 pp | Hardcover
Price: $ 165.00
Table of Contents
Dedication v
Preface xvii
Acknowledgments xix
Chapter 1: Introduction to CT
1.1 How Does CT Work 1
1.2 Data Collection 5
1.2.1 Axial/Sequential Mode 10
1.2.2 Helical/Spiral Mode 10
1.2.3 Cine/Perfusion Mode 11
1.2.4 Shuttle Mode 11
1.2.5 CT Fluoroscopy 11
1.2.6 Gantry Tilting 12
1.2.7 Scan Angular Range 13
1.2.8 Detector Coverage 15
1.2.9 CBCT 16
1.3 Flavors of CT 17
1.3.1 Diagnostic Radiology 18
1.3.2 Interventional Radiology CT Fluoroscopy 20
1.3.3 Baggage Scanning CT 21
1.3.4 Interventional Radiology C-arm (CBCT) 21
1.3.5 Dedicated Head Scanner 22
1.3.6 Mobile CT 22
1.3.7 Dental CT 23
1.3.8 CT Simulation for Radiation Therapy 24
1.3.9 Image-Guided Radiation Therapy 25
1.3.10 TomoTherapy® and MVision® 26
1.3.11 Dedicated Breast CT 27
1.3.12 Synchrotron CT 28
1.3.13 Small Animal Imaging 29
1.3.14 Industrial CT 30
1.4 The Most Common Misconceptions in Medical CT Today 30
References 33
Chapter 2: Example CT Exam Workflows
2.1 Patient Preparation 35
2.1.1 Removable Artifact-Causing Objects 36
2.1.2 Pre-Scan Preparation and Questions 37
2.1.3 Inpatient Setting Prep and Transport 38
2.1.4 Outpatient Setting Prep and Transport 38
2.1.5 Emergency Department Setting Prep and Transport 39
2.2 Example MDCT Scan Workflow: Routine Non-Contrast Head 39
2.3 Scan Time Anatomical Landmark Guide 49
2.3.1 Example Anatomical Landmarks from CT Localizers 50
2.3.2 Example Scan Ranges 52
2.3.3 Bolus Tracking Locations 56
2.3.4 Basic Cross-Sectional CT Anatomy Tutorial 58
References 75
Chapter 3: Image Quality and System Performance
3.1 Image Noise 77
3.1.1 Factors that Influence Image Noise 81
3.1.2 Variability in ROI Measurements of CT Number 83
3.2 Image Contrast 85
3.3 CNR 87
3.4 Spatial Resolution 90
3.5 Temporal Resolution 94
3.6 Scatter 97
3.7 Slice Thickness 99
3.8 Other System Specifications Impacting Image Quality 101
3.8.1 DQE 101
3.8.2 Detector Dynamic Range and Bit Depth 101
3.8.3 Detector Element Size 102
3.8.4 Focal Spot Size 102
3.8.5 SID/SOD Magnification and Image Resolution 102
References 104
Chapter 4: Dose
4.1 Putting CT Ionizing Dose Risk in Perspective 111
4.2 Radiation Damage from CT and Guidance on Dose Thresholds 112
4.3 Overview of Patient Dose Surrogates 116
Understanding SSDE (Size-Specific Dose Estimate) 121
4.4 Diagnostic CT Dose 122
4.5 Shielding 134
4.5.1 Shielding in Diagnostic CT: Physical Shields 134
Guidance for PE Studies on Pregnant Patients 139
4.5.2 Shielding in Diagnostic CT: mA Modulation 140
4.5.3 Shielding in Diagnostic CT: Collimation 141
References 142
Chapter 5: Reconstruction Options
5.1 Slice Thickness and Interval 149
5.2 Reconstruction Kernels (Algorithms) 153
Vendor-Specific Options 155
5.3 Reconstruction Display Field of View/ Matrix Size 168
5.4 Display Window Width and Level 171
5.5 Nonlinear or Iterative Denoising Options 176
5.6 Beam Hardening Corrections 182
5.7 Clinical Recommendations: Master Protocol Concept for Reconstruction 185
References 188
Chapter 6: Acquisition Parameters and the Master Protocol Concept
6.1 Effective mAs 190
6.2 Pitch, Collimation, and Image Quality 194
6.3 Pitch, Collimation, and Dose 199
6.4 Why We Need Size-Based Protocols 203
6.5 Master Protocol Concept: Acquisition Parameters 206
References 224
Chapter 7: Automatic Exposure Control
7.1 Basic Principles of AEC 227
7.1.1 Tube Current Modulation 233
7.1.2 Beam Energy Modulation 235
7.2 Practical AEC Advice 237
7.3 MDCT Vendor Implementation Differences 241
7.3.1 GE 246
7.3.2 Canon (Toshiba) 248
7.3.3 Philips 252
7.3.4 Siemens 252
7.3.5 Rosetta Stone for CT AEC Systems? 253
References 255
Chapter 8: CT Contrast
8.1 Overview of CT Contrast and Injectors 257
8.2 Contrast Progression and Appearance in the Body 262
8.3 Contrast Injection Protocols and Protocol Parameters 263
8.4 Example Contrast-Enhanced Images 271
References 280
Chapter 9: Beam Energy, CT Number, and Dual-Energy CT
9.1 Beam Energy 282
Is It keV or kVp? 283
9.2 CT Number 286
9.3 Dual-Energy and Spectral Imaging 290
9.3.1 X-ray Attenuation Theory 290
9.3.2 Clinical Realization of Dual Energy 299
9.3.3 Types of Dual-Energy Images 302
9.3.4 Avoiding Confusion When Interpreting Basis Material Images 304
References 306
Chapter 10: Patient Positioning
10.1 Motivation for Patient Positioning 309
10.2 Position and Dose Modulation 315
10.3 Position and Spatial Resolution 318
10.4 Position and Temporal Resolution 320
10.5 Position and CT Number/Noise Uniformity 322
References 327
Chapter 11: Protocol Management
11.1 The Importance of Protocol Uniformity 329
11.1.1 How Scan Time May Affect Image Appearance 331
11.1.2 How Slice Thickness May Affect Image Appearance 332
11.1.3 How Slice/Reconstruction Interval May Affect Image Appearance 333
11.1.4 How Contrast Volume May Affect Image Appearance 333
11.1.5 How Contrast Strength May Affect Image Appearance 333
11.1.6 How Contrast-to-Scan Timing May Affect Image Appearance 334
11.1.7 How Contrast Injection Rate May Affect Image Appearance 334
11.1.8 How Reconstruction Kernel/Algorithm Sharpness May Affect Image Appearance 334
11.1.9 How Dose May Affect Image Appearance 335
11.1.10 How Beam Energy May Affect Image Appearance 335
11.1.11 How Scanner Platform May Affect Image Appearance 335
11.2 CT Protocol Optimization Team: Why We Need a Team 335
11.3 Components of a Protocol 342
11.4 Solutions for Protocol Management 348
11.5 Costs Associated with Protocol Management 352
References 353
Chapter 12: Protocol Review
12.1 Overview of Dose Tracking Software 355
12.1.1 Basic Functionality 355
12.1.2 IT Connections 357
12.1.3 Pitfalls of Dose Comparisons 358
12.2 How to Review Protocols Using Dose Information 360
12.3 Radiologist Image Review 365
12.4 Physicist and Technologist Protocol Review 369
References 372
Chapter 13: Clinical MDCT
13.1 Head/Neuro Imaging 375
13.2 Torso Imaging 384
13.3 Cardiac Gated Imaging 391
13.4 Musculoskeletal Imaging 396
13.5 Special Considerations for Pediatric Patients 399
References 401
Chapter 14: CBCT and Non-Diagnostic CT
14.1 CBCT 403
14.2 Industrial and Micro CT 410
14.3 CT Simulation (Radiation Therapy Treatment Planning) 416
References 421
Chapter 15: Informatics and CT
15.1 CT Dose Reporting 423
15.2 Networking 428
15.2.1 Master Protocol Concept in Networking 431
15.2.2 Digital Footprints in Radiology CT Workflows 431
15.3 Hanging Protocols 435
References 436
Chapter 16: Artifacts
16.1 Types of CT Artifacts 437
16.2 Workflow for Artifact Identification from the Reading Room 441
16.3 Workflow for Artifact Identification at the Scanner 443
16.3.1 Workflow for Being Sure You Have an Artifact that is Scanner-Based 443
16.3.2 Workflow for Figuring Out Which Scan Modes an Artifact Will Appear in or Which
Scanner Component/Process is Failing 444
16.4 Catalog of CT Artifact Examples 445
16.4.1 Isocentric Artifacts 445
16.4.2 Non-Isocentric Artifacts 447
References 508
Chapter 17: Buyer’s Guide of Optional Features in CT
17.1 MDCT Scanner Options 510
17.1.1 Software Ownership with Refurbished Scanners 511
17.1.2 Service Options 511
17.1.3 Apps Training 513
17.1.4 Slice Number 514
17.1.5 Option Bundling and Dependencies 516
17.1.6 Diagnostic CT-Specific Scanner Options 517
17.1.7 Radiation Therapy Scanner Options 521
17.1.8 PET/CT 523
17.1.9 Interventional CT Scanner Options 523
17.2 Scanner Options General to All Settings 524
17.2.1 Metal Artifact Reduction 524
17.2.2 RIS/PACS/EMR Workflow Options 525
17.2.3 3D Processing Workstations 525
17.3 Auxiliary Equipment Purchases 526
17.4 Indication-Specific MDCT Scanner Needs 528
17.5 Site Planning 528
References 531
Appendix A: Whitepaper—Using the Gammex Mercury 4.0 Phantom for Common Clinical Tasks in CT 533
Appendix B: “Homebrew” Dual Energy 559
Appendix C: Table of Figures Showing Common CT Artifacts 567