This book acts as a primer for radiographers upon performing computed tomography (CT) examinations. The focus resides in radiation physics, radiobiology, anatomy, imaging protocols and image evaluation. It seeks to provide readers insight into the practical and innovative approaches within CT, backed up with key literature and examples in practice. Recent innovations and the importance of new technology to acquire enhanced quality remain a focal point. These are essential in understanding the importance of dose optimization, patient anatomy and common pathology observed. Patient care will remain central in this book, supported with a dedicated chapter discussing effective communication, patient education, informed consent, coupled with the assessment of laboratory results and vital signs. The editors draw from recent publications and clinical expertise, supported with the growing trend of technological advances utilized within the CT environment. Critically, this volume focuses on the role of CT for an array of audiences but, more specifically, undergraduate and postgraduate radiographers worldwide.
Author(s): Shayne Chau, Christopher M Hayre
Edition: 1
Publisher: CRC Press
Year: 2022
Language: English
Tags: Computed Tomography; Radiography; Medical Imaging; Radiology & Nuclear Medicine; Diagnostic Imaging
Cover
Half Title
Series Page
Title Page
Copyright Page
Dedication
Table of Contents
Acknowledgements
Preface
Editors
Contributors
SECTION 1 Physics, Principles and Radiobiology in Computed Tomography
Chapter 1 Computed Tomography in Medical Imaging
Chapter 2 Physics and Principles of Computed Tomography
Introduction
Why Computed Tomography?
CT Instruments
Major CT Components
Other CT Components
Digital Images and Display
Digital Images – A Brief Overview
Display of Digital Images
Window Width/Window Level
Image Capture and Reconstruction
CT Image Capture
CT Image Reconstruction Problem
Helical/Spiral Scanning
CT Image Reconstruction
Hounsfield Units/CT Numbers
Thins vs Thicks
Scan and Display Field of View
Scouts/Topograms/Planning Scans
Image Quality in CT
Contrast Resolution, Spatial Resolution and Noise
Spatial Resolution
Contrast Resolution
Noise
Contrast Resolution, Spatial Resolution and Noise Relationship
Artefacts
Conclusion
References
Bibliography
Chapter 3 Radiobiology
Introduction
Collective Effective Radiation Dose and the Contribution of Computed Tomography (CT) Dose
The Effects of Radiation on the Human Body
Measurement of CT Doses
Potential Radiation Risks from CT Examinations
Evidence for Radiobiological Damage of X-Rays
Radiation Hormesis
CT Radiation Dose in Children
Conclusion
References
SECTION 2 Dose Optimization
Chapter 4 Dose Optimization
Introduction
Biological Effects of Radiation Exposure
Radiation Protection Philosophy
ICRP System
Justification
Optimization
Image Quality
The Need to Optimize CT Doses
CT Dosimetry Fundamentals
Metrics Display
Dose Metrics Calculation
Technical Factors Affecting the Dose in CT
Exposure Technique Factors
Pitch
Collimation and Slices
Overbeaming and Overranging
AEC and Image Quality Index
Patient Positioning
Iterative Image Reconstruction
Dose Optimization in CT
Research on Dose Optimization and Image Quality
Findings from CT Dose Optimization Studies
The Role of the Radiographer in Dose Optimization
Conclusion
References
SECTION 3 Patient Care
Chapter 5 Patient Care in Computed Tomography
Introduction
Patient Communication and Patient Preparation
Dietary Restrictions
Sedation
Contrast Agents: Contrast Specifications
Contrast Complications and Adverse Effect
Oral & Rectal Contrast
Considerations for High-Risk Patients
Pregnant Women
Paediatrics
Dialysis Patients
Diabetic Patients & Metformin
Iodine Allergy
Hyperthyroidism
References
SECTION 4 Cross-Sectional Anatomy
Chapter 6 Cross-Sectional Anatomy of the Head
Axial CT – At the Level of the Cephalic End of Falx Cerebri
Axial CT – At the Level of Straight Sinus
Axial CT – At the Level of Pineal Gland
Axial CT – At the Level of Great Cerebral Vein
Axial CT – At the Level of the Confluence of Sinuses
Axial CT – At the Level of the Genu of Corpus Callosum
Axial CT – At the Level of the Terminal Part of Basilar Artery in Prepontine Cistern
Axial CT – At the Level of External Occipital Protuberance
Axial CT – At the Level of Ethmoidal Air Cells
Axial CT – At the Level of Posterior Nasal Choanae
Chapter 7 Cross-Sectional Anatomy of the Neck
Axial CT – At the Level of the Condyle of the Mandible
Axial CT – At the Level of Inferior Nasal Concha
Axial CT – At the Level of C1
Axial CT – At the Level of the Dens
Axial CT – At the Level of Posterior Arch of C2
Axial CT – At the Level of C3
Axial CT – At the Level of C4
Axial CT – At the Level of C5
Axial CT – At the Level of C6
Chapter 8 Cross-Sectional Anatomy of the Thoracic System
C7/T1 Vertebral Level
T2/T3 Thoracic Vertebral Level
T3/T4 Thoracic Vertebral Level
T5 Thoracic Vertebral Level
T9 Thoracic Vertebral Level
Chapter 9 Cross-Sectional Anatomy of the Abdominopelvic System
Introduction
T11 Images from Lower Thoracic Vertebral Levels Show Both the Thorax and Abdomen
T12 Upper
T12 Lower – Splenic Arteries Pancreas
Coronal Posterior Abdomen
L1 Lower
L2 – Transverse Colon Head of Pancreas
L3
L4
L5/S1 – Iliac Vessels
S3
Mid-Sagittal – Male
Coccyx – Male
Coccyx – Female
Chapter 10 Cross-Sectional Anatomy of the Upper Limb
T1 Vertebral Level
Left Mid Arm Level
Left Distal Arm Level
Left Cubital Fossa Level
Left Proximal Radioulnar Joint Level
Left Mid Forearm Level
Left Distal Forearm/Proximal Wrist Level
Left Mid Carpal Level
Left Distal Carpal Level
Chapter 11 Cross-Sectional Anatomy of the Lower Limb
Superior Pubic Rami Level
Ischial Tuberosity Level
Bilateral Mid-Femoral Level
Bilateral Distal-Femoral Level
Bilateral Patellofemoral Joint Level
Knee Joint Level
Proximal Tibiofibular Joint Level
Mid Leg Level
Distal Tibiofibular Joint Level
Ankle Joint Level
Tarsal Bones (Oblique View)
SECTION 5 Imaging Procedures
Chapter 12 Imaging of the Head
Introduction
Head
Considerations
CT Head Protocol
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
Contrast Phase and Timing
CT Sinuses Protocol
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
CT Orbits/Face Protocol
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
CT Petrous Bone (Internal Auditory Meatus) Protocol
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
CT Head Angiogram (Circle of Willis) Protocol
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
References
Chapter 13 Imaging of the Neck
Introduction
Considerations
CT Cervical Spine Protocol
Commonly Presenting/Significant Pathologies
CT Soft Tissue Neck Protocol
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
CT Head and Neck Angiogram Protocol
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
Reference
Chapter 14 Imaging of Paediatric Patients
Introduction
What Is a Paediatric Patient?
Paediatric Patients in the Medical Imaging Department
Neonate–Infants (0–6 Months)
Feed and Wrap Technique
Toddler–Preschool (6 Months to 4 Years)
Young Children and Pre-Teens (5–12 years)
Adolescents (13–16 Years)
Environment
Justification
Contrast
IV Contrast
Oral Contrast
Protocols
Vascular Access and Contrast Timing
Scan Speed
Scan Direction
Dose Optimisation
Topogram
Bolus Tracking or Test Bolus
Scan Acquisition
Patient Positioning
Shielding
Reconstruction
Head and Neck Imaging
CT Head
Non-Contrast CT Head Protocol
Commonly Presenting/Significant Pathologies
Pre-Acquisition
Patient Positioning
Planning
Protocol Considerations
Image Reconstruction
Low Dose Non-Contrast CT Head
Commonly Presenting/Significant Pathologies
Contrast CT Head Protocol
Soft Tissue Neck
Commonly Presenting/Significant Pathologies
Pre-Acquisition
Patient Positioning
Planning
Protocol Considerations
Contrast Phase and Timing
Image Reconstruction
Cervical Spine
Patient Positioning
Planning
Image Reconstruction
Torso Imaging
Chest
Non-Contrast Chest
Commonly Presenting/Significant Pathologies
Chest with Contrast
Commonly Presenting/Significant Pathologies
Pre-Acquisition
Patient Positioning
Planning
Image Reconstruction
HRCT (High-Resolution Computed Tomography) Chest
Commonly Presenting/Significant Pathologies
Patient Positioning
Planning
Image Reconstruction
Portal Venous Phase Abdomen
Commonly Presenting/Significant Pathologies
Patient Positioning
Planning
Contrast Phase and Timing
Image Reconstruction
Multi-Region Studies
Head, Neck, Chest, Abdomen and Pelvis – Malignancy
Head, C-Spine, Chest, Abdomen and Pelvis – Multi-Trauma
Pre-Acquisition
Patient Positioning
Planning
Contrast Phase and Timing
Axial Skeleton
Thoracic and Lumbar Spine
Appendicular Skeleton
Extremities (Non-contrast)
References
Chapter 15 Imaging of the Thorax
Introduction
CT Chest Protocol
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
Use of Intravenous Contrast
Acquisition and Reconstruction
High-Resolution CT (HRCT) of the Chest
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
CT Pulmonary Angiography (CTPA)
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Patient Positioning
Planning
Protocol Considerations
CT Calcium Score
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Pre-scan
Patient Positioning
Planning
Protocol Considerations
CT Coronary Angiography (CTCA)
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Pre-scan
Patient Positioning
Planning
Protocol Considerations
CT Gated Aortogram
Commonly Presenting/Significant Pathologies
Approaches to Imaging
Pre-scan
Patient Positioning
Planning
Protocol Considerations
References
SECTION 6 Image Evaluation
Chapter 16 Introduction to CT Image Interpretation
Introduction
Clinical History
Systematic Methods
A
Adequacy
Anatomy
Window Level/Width
Reconstruction
Hounsfield Units
A
B
C
D
E
S
Normal vs Abnormal and Normal Variants
Failure to Search
Language Used for Reporting
Conclusion
References
Chapter 17 CT Head Image Evaluation
Introduction
Writing a Report
Radiological Errors
Haemorrhages
Intra-axial Haemorrhage
Extradural Haemorrhage
Subdural
Subarachnoid Haemorrhage (SAH)
Strokes
Hyperacute/Acute Phase
Subacute Phase
Chronic Stage.
Brain Tumours
Meningioma
Glioma
Metastatic Tumours
Obstructive Hydrocephalus
Aneurysms
Skull Fractures
Cerebral Atrophy/Ageing of the Brain
Conclusion
References
Chapter 18 CT Thoracic Image Evaluation
Introduction
Clinical History
Systematic Review
Using the ABCDES System
Emphysema
Pulmonary Embolism
Lung Neoplasm and Pulmonary Metastases
Tuberculosis (TB)
Pleural Effusion
Pneumothorax
COVID-19
Conclusion
Acknowledgement
References
Chapter 19 CT Abdomen Image Evaluation
Introduction
Clinical History
Systematic Method
Ascites
Cholelithiasis
Hydronephrosis
Jaundice
Placement of Nasogastric Tube
Colostomy
Pelvic Abscess
Abdominal Aortic Aneurysm
Conclusion
Acknowledgement
References
Chapter 20 CT Image Evaluation in Oncology
Introduction
CT
Contrast
Luminal Contrast
The Tumour, Nodes, Metastases (TNM) Approach
NB. Not all Masses are Cancer and not all Cancers are Solitary
Initial Diagnosis and Staging of Common Cancers
Lung Carcinoma
T
N
M
Colorectal Carcinoma
Clues
Mimics
T
N
M
Breast Cancer
Clues
Important Mimics
T
N
M
Prostate Carcinoma
Mimics
Clues
T
N
M
Melanoma
Mimics – Other Hypervascular Metastases
Mimics
Clues
T
N
M
Tumours of the Brain
Examples of Intra and Extra-Axial Masses Include
Mimics
Clues
Additional Roles for CT in Cancer Diagnosis
Acknowledgements
References
Index
