Оглавление
Euclid Seeram. A Comprehensive Guide to Radiographic Sciences and Technology
Table of Contents
List of Tables
List of Illustrations
Guide
Pages
A Comprehensive Guide to Radiographic Sciences and Technology
Dedication
Foreword
Preface
PURPOSE
CORE OBJECTIVES
USE OF THESE OBJECTIVES AND CONTENT
Acknowledgments
1 Radiographic sciences and technology: an overview
RADIOGRAPHIC IMAGING SYSTEMS: MAJOR MODALITIES AND COMPONENTS
RADIOGRAPHIC PHYSICS AND TECHNOLOGY
Essential physics of diagnostic imaging
Digital radiographic imaging modalities
Radiographic exposure technique
Image quality considerations
Computed tomography – physics and instrumentation
Quality control
Imaging informatics at a glance
RADIATION PROTECTION AND DOSE OPTIMIZATION
Radiobiology
Radiation protection in diagnostic radiography
Technical factors affecting dose in radiographic imaging
Radiation protection regulations
Optimization of radiation protection
Bibliography
2 Digital radiographic imaging systems: major components
FILM‐SCREEN RADIOGRAPHY: A SHORT REVIEW OF PRINCIPLES
DIGITAL RADIOGRAPHY MODALITIES: MAJOR SYSTEM COMPONENTS
Computed radiography
Flat‐panel digital radiography
Digital fluoroscopy
Digital mammography
Computed tomography
IMAGE COMMUNICATION SYSTEMS
Picture archiving and communication system
References
3 Basic physics of diagnostic radiography
STRUCTURE OF THE ATOM
Nucleus
Electrons, quantum levels, binding energy, electron volts
ENERGY DISSIPATION IN MATTER
Excitation
Ionization
TYPES OF RADIATION
Electromagnetic radiation
Wave–particle duality
Particulate radiation
X‐RAY GENERATION
X‐RAY PRODUCTION
Properties of x‐rays
Origin of x‐rays
Characteristic radiation
Bremsstrahlung radiation
X‐RAY EMISSION
X‐RAY BEAM QUANTITY AND QUALITY
Factors affecting x‐ray beam quantity and quality
kV
mA
Target material
X‐ray beam filtration
Voltage waveform
A general relationship
INTERACTION OF RADIATION WITH MATTER
Mechanisms of interaction in diagnostic x‐ray imaging
Classical scattering
Compton scattering
Photoelectric absorption
RADIATION ATTENUATION
Linear attenuation coefficient
Mass attenuation coefficient
Half value layer
RADIATION QUANTITIES AND UNITS
Bibliography
4 X‐ray tubes and generators
PHYSICAL COMPONENTS OF THE X‐RAY MACHINE
COMPONENTS OF THE X‐RAY CIRCUIT
The power supply to the x‐ray circuit
The low‐voltage section (control console)
The high‐voltage section
TYPES OF X‐RAY GENERATORS
Three‐phase generators
High‐frequency generators
Power ratings
THE X‐RAY TUBE: STRUCTURE AND FUNCTION
Major components
SPECIAL X‐RAY TUBES: BASIC DESIGN FEATURES
Double‐bearing axle
HEAT CAPACITY AND HEAT DISSIPATION CONSIDERATIONS
X‐RAY BEAM FILTRATION AND COLLIMATION
Inherent and added filtration
Effects of filtration on x‐ray tube output intensity
Half‐value layer
Collimation
References
5 Digital image processing at a glance
DIGITAL IMAGE PROCESSING
Definition
Image formation and representation
Processing operations
CHARACTERISTICS OF DIGITAL IMAGES
GRAY SCALE PROCESSING
Windowing
CONCLUSION
References
6 Digital radiographic imaging modalities: principles and technology
COMPUTED RADIOGRAPHY
Essential steps
Basic physical principles
Response of the IP to radiation exposure
The standardized exposure indicator
FLAT‐PANEL DIGITAL RADIOGRAPHY
What is FPDR?
Types of FPDR systems
Basic physical principles of indirect and direct flat‐panel detectors
The fill factor of the pixel in the flat‐panel detector
Exposure indicator
Image quality descriptors for DR systems
Continuous quality improvement for DR systems
DIGITAL FLUOROSCOPY
Digital fluoroscopy modes
II‐Based digital fluoroscopy characteristics
Flat‐panel digital fluoroscopy characteristics
DIGITAL MAMMOGRAPHY
Screen‐film mammography – basic principles
Imaging system characteristics
Limitations of SFM
Full‐field digital mammography – major elements
Imaging system characteristics
DIGITAL TOMOSYNTHESIS AT A GLANCE
Imaging system characteristics
Synthesized 2D digital mammography
References
7 Image quality and dose
THE PROCESS OF CREATING AN IMAGE
IMAGE QUALITY METRICS
Contrast
Contrast resolution
Spatial resolution
Noise
The concept of quantum noise
Contrast‐to noise ratio
Signal‐to‐noise ratio
ARTIFACTS
IMAGE QUALITY AND DOSE
Digital detector response to the dose
Detective quantum efficiency
References
8 The essential technical aspects of computed tomography1
BASIC PHYSICS
Radiation attenuation
TECHNOLOGY
Data acquisition: principles and components
Image reconstruction
Filtered back projection
Iterative reconstruction
Image display, storage, and communication
MULTISLICE CT: PRINCIPLES AND TECHNOLOGY
Slip‐ring technology
X‐ray tube technology
Interpolation algorithms
MSCT detector technology
Selectable scan parameters
Isotropic CT imaging
MSCT image processing
IMAGE POSTPROCESSING
Windowing
3‐D image display techniques
IMAGE QUALITY
Spatial resolution
Contrast resolution
Noise
RADIATION PROTECTION
CT dosimetry
Factors affecting patient dose
Optimizing radiation protection
Box 8.1 Essential elements for technologists to optimize CT dose
CONCLUSION
References
Note
9 Fundamentals of quality control
INTRODUCTION
DEFINITIONS
ESSENTIAL STEPS OF QC
QC RESPONSIBILITIES
STEPS IN CONDUCTING A QC TEST
THE TOLERANCE LIMIT OR ACCEPTANCE CRITERIA
PARAMETERS FOR QC MONITORING
Major parameters of imaging systems
QC TESTING FREQUENCY
TOOLS FOR QC TESTING
THE FORMAT OF A QC TEST
PERFORMANCE CRITERIA/TOLERANCE LIMITS FOR COMMON QC TESTS
Radiography. Visual inspection
Filtration
Collimation
Focal spot size
kV accuracy
Exposure timer accuracy
Exposure linearity
Exposure uniformity
Exposure index, dynamic range, and noise, spatial resolution, and contrast detectability
Electronic display performance
Computed radiography: qualitative acceptance criteria – three examples
Fluoroscopy
REPEAT IMAGE ANALYSIS
Corrective action/Reasons for rejection
COMPUTED TOMOGRAPHY QC TESTS FOR TECHNOLOGISTS
The ACR CT accreditation phantom
The ACR action limits for tests done by technologists
Artifact evaluation
References
10 PACS and imaging informatics at a glance
INTRODUCTION
PACS CHARACTERISTIC FEATURES. Definition
Core technical components
IMAGING INFORMATICS
Enterprise imaging
Cloud computing
Big Data
Artificial intelligence
Machine learning
Deep learning
APPLICATIONS OF AI IN MEDICAL IMAGING
AI in CT image reconstruction
Ethics of AI in radiology
References
11 Basic concepts of radiobiology
WHAT IS RADIOBIOLOGY?
BASIC CONCEPTS OF RADIOBIOLOGY
Generalizations about radiation effects on living organisms
Relevant physical processes
Radiosensitivity
Dose–response models
Radiation interactions in tissue: target theory, direct and indirect action
The target theory
Direct action
Indirect action
DNA and chromosome damage
DNA damage
Chromosome damage
EFFECTS OF RADIATION EXPOSURE TO THE TOTAL BODY
Hematopoietic of bone marrow syndrome
Gastrointestinal syndrome
Central nervous system (CNS) syndrome
DETERMINISTIC EFFECTS
STOCHASTIC EFFECTS
Tissue effects
Life‐span shortening
Radiation‐induced cancers
Hereditary effects
RADIATION EXPOSURE DURING PREGNANCY
References
12 Technical dose factors in radiography, fluoroscopy, and CT
DOSE FACTORS IN DIGITAL RADIOGRAPHY
The x‐ray generator
Exposure technique factors
X‐ray beam filtration
Collimation and field size
The SID and SSD
Patient thickness and density
Scattered radiation grid
The sensitivity of the image receptor
DOSE FACTORS IN FLUOROSCOPY
Fluoroscopic exposure factors
Fluoroscopic equipment factors
CT RADIATION DOSE FACTORS AND DOSE OPTIMIZATION CONSIDERATIONS
Dose distribution in the patient
CT dose metrics
Factors affecting the dose in CT
Dose optimization overview
References
13 Essential principles of radiation protection
INTRODUCTION
WHY RADIATION PROTECTION?
Categories of data from human exposure
Radiation dose–risk models
Summary of biological effects
Radiation protection organizations/reports
OBJECTIVES OF RADIATION PROTECTION
RADIATION PROTECTION PHILOSOPHY
Justification
Optimization
Dose limits
PERSONAL ACTIONS
Time
Shielding
Distance
RADIATION QUANTITIES AND UNITS
Sources of radiation exposure
Quantities and units
PERSONNEL DOSIMETRY
OPTIMIZATION OF RADIATION PROTECTION
Regulatory and guidance recommendations
Diagnostic reference levels (DRLs)
Gonadal shielding: past considerations
X‐ray room shielding
CURRENT STATE OF GONADAL SHIELDING
References
Index
WILEY END USER LICENSE AGREEMENT
