Читать книгу A Comprehensive Guide to Radiographic Sciences and Technology - Euclid Seeram - Страница 4

1 Chapter 2Figure 2.1 The overall system components of film screen radiography (FSR).Th...Figure 2.2 A plot of the OD as a function of the log of the relative radiati...Figure 2.3 DR detectors have wide‐exposure latitude and image postprocessing...Figure 2.4 The overall major system components of any DR modality includes a...Figure 2.5 The major components of a CR system include the imaging plate (IP...Figure 2.6 The major system components of a FPDR system include an x‐ray gen...Figure 2.7 The major system components of a DF system consist of a flat‐pane...Figure 2.8 The basic concept for DBT and DRT is related to the principle und...Figure 2.9 In CT, the patient is scanned as the x‐ray tube coupled to specia...Figure 2.10 The major system components of a PACS make use of digital techno...

2 Chapter 3Figure 3.1 Bohr's planetary model of the atom shows a dense nucleus surround...Figure 3.2 During excitation of the atom, electrons are not ejected, but rat...Figure 3.3 The production of characteristic radiation.Figure 3.4 Bremsstrahlung radiation is produced when a high‐speed electron i...Figure 3.5 The general form and shape of both the discrete and continuous x‐...Figure 3.6 The effect of kV on the intensity and quality of x‐rays. Note tha...Figure 3.7 The effects of mA on x‐ray spectra. The area under the curve incr...Figure 3.8 For higher atomic number target materials, there is an increase i...Figure 3.9 The effect of filtration on the x‐ray spectra. For high filtratio...Figure 3.10 The effect of rectification on the x‐ray spectra. For three‐phas...Figure 3.11 Classical scattering. A low‐energy photon is absorbed by the ato...Figure 3.12 Compton scattering is a photon–electron interaction in which the...Figure 3.13 Photoelectric absorption occurs when an incident photon interact...Figure 3.14 The difference between the attenuation of a homogeneous beam and...

3 Chapter 4Figure 4.1 The physical components of the x‐ray machine. See text for furthe...Figure 4.2 The major components of the x‐ray generator. See text for further...Figure 4.3 An electrical circuit diagram of the x‐ray machine. The circuit i...Figure 4.4 A generalized schematic of a high‐frequency generator. See text f...Figure 4.5 The essential components of an x‐ray tube include the cathode ass...

4 Chapter 5Figure 5.1 Mathematical images include continuous and discrete functions. Th...Figure 5.2 In a digital radiography imaging system, analog signals must be c...Figure 5.3 The major characteristics of a digital image include a matrix, pi...Figure 5.4 Tissue voxel information is converted into numerical values and e...Figure 5.5 The histogram is a graph of the number of pixels in the entire im...Figure 5.6 The lookup table (LUT) uses the input image pixel values and chan...Figure 5.7 Windowing is the most common technique that technologists and rad...Figure 5.8 The displayed WW and WL values are always shown on the image. Whi...Figure 5.9 When the WL is decreased, the image becomes lighter since more of...

5 Chapter 6Figure 6.1 Four essential steps in the CR imaging process. See text for furt...Figure 6.2 This figure shows that after the latent image is rendered visible...Figure 6.3 The essential steps for calculation of the DI in the new EI parad...Figure 6.4 The acceptable range of DI numbers is approximately −1 to +1, and...Figure 6.5 A flat‐panel DR imaging system is based on the use of a flat‐pane...Figure 6.6 Two types of flat‐panel digital radiography detectors have become...Figure 6.7 The fill factor then is defined as the ratio of sensing area of t...Figure 6.8 The major technical components of a typical II‐based DF imaging c...Figure 6.9 The components of the II tube and their layout include the input ...Figure 6.10 Artifacts such as pincushion distortion (due to the curvature of...Figure 6.11 The major system components of a FPDF imaging system (real‐time ...Figure 6.12 The fundamental process of digital tomosynthesis includes at lea...Figure 6.13 The fundamental principles of DT. See text for further explanati...Figure 6.14 The process for generating a synthesized 2D image from the DBT i...

6 Chapter 7Figure 7.1 The process of creating a diagnostic quality image. The goal of t...Figure 7.2 Technical exposure factors such as mAs and kV affect the dose to ...Figure 7.3 A schematic illustrating the difference between subject contrast ...Figure 7.4 In digital radiography, contrast resolution is described bradiogr...Figure 7.5 The effect of bit depth on the visual appearance of shades of gra...Figure 7.6 Illustration of spatial resolution. While (a) shows a sharp image...Figure 7.7 The size of the x‐ray tube focal spot influences the spatial shar...Figure 7.8 Spatial resolution can be measured by metrics such as the line pa...Figure 7.9 Two images with different levels of noise. (a) Shows an image wit...Figure 7.10 The presence of noise in an image destroys image quality and aff...Figure 7.11 The concept of quantum noise. The photons from the x‐ray tube fa...Figure 7.12 The visual effect of high and low mAs on image noise. See text f...Figure 7.13 A conceptual approach to understanding SNR. See text for further...Figure 7.14 The relationship between image noise and patient dose, and visua...Figure 7.15 The DQE can be thought of as the efficiency of the digital detec...

7 Chapter 8Figure 8.1 The computed tomography (CT) scanner consists of three primary sy...Figure 8.2 CT data collection. The x‐ray tube and detectors rotate around th...Figure 8.3 The difference between the attenuation behavior of two types of x...Figure 8.4 Attenuation of a homogeneous beam of radiation is exponential and...Figure 8.5 As a single ray of the x‐ray beam passes through a stack of voxel...Figure 8.6 Attenuation through a single voxel. The attenuation value is conv...Figure 8.7 The matrix of CT numbers (numerical image = gray levels) must be ...Figure 8.8 Multislice CT (MSCT) scanners use fan‐beam geometry to scan the v...Figure 8.9 Primary components of a CT scanner data acquisition system: the x...Figure 8.10 Flow charts showing the primary steps of the filtered back‐proje...Figure 8.11 A visual comparison between CT images obtained at 180 mAs and re...Figure 8.12 A main difference between conventional slice‐by‐slice CT scannin...Figure 8.13 The main components of two types of scintillation detectors: con...Figure 8.14 A main difference between single‐slice CT and MSCT is the detect...Figure 8.15 Two types of 2‐D detector arrays used in MSCT scanners: the matr...Figure 8.16 The effect of pitch on dose and image quality in MSCT. As the pi...Figure 8.17 The geometry of isotropic and anisotropic voxels. The overall go...Figure 8.18 A graphic illustration of the effect of window width (WW) on a C...Figure 8.19 The effect of window level (WL) on image brightness. As the wind...Figure 8.20 Creating 3‐D CT images involves four primary steps: image acquis...

8 Chapter 9Figure 9.1 The relationships between CQI, QA, and QC. See text for further e...Figure 9.2 The essential steps of QC include acceptance testing, routine per...Figure 9.3 Conducting QC tests for the evaluation of equipment performance r...Figure 9.4 Evaluation of the results of QC tests require established accepta...Figure 9.5 A useful tool to evaluate display performance in digital radiogra...Figure 9.6 Qualitative acceptance criteria for three QC tests of the CR IP, ...Figure 9.7 A general schematic of the ACR CT QC accreditation phantom. The p...Figure 9.8 Artifacts can arise from a number of different sources leading to...

9 Chapter 10Figure 10.1 The functional organization of the major system components of a ...Figure 10.2 Two types of image compression, namely, lossless compression or ...Figure 10.3 An example of one element of DICOM^® which identifies a set ...Figure 10.4 The four Vs used to characterize Big Data. See text for further ...Figure 10.5 Two subsets of AI include machine learning (ML) and deep learnin...

10 Chapter 11Figure 11.1 The sequence of events in which radiation damage in cells occurs...Figure 11.2 A more elaborate scheme leading to biological damage that shows ...Figure 11.3 High‐LET radiation (b) produces more ionizations and free radica...Figure 11.4 Two categories of dose–response models: the linear dose–response...Figure 11.5 Direct and indirect action on the target molecule DNA. Direct ac...

11 Chapter 12Figure 12.1 The general radiographic system components affecting the dose to...Figure 12.2 The effect of SID on dose to the patient. A short SID increases ...Figure 12.3 The major components of two types of fluoroscopy systems in use ...Figure 12.4 Electronic magnification in digital fluoroscopy includes binning...Figure 12.5 The distribution of the dose in the patient in radiography is no...Figure 12.6 The typical dose distribution in CT is a bell‐shaped curve. The ...Figure 12.7 The difference between overbeaming and overranging in CT. Adapti...

12 Chapter 13Figure 13.1 The three philosophical pillars of the ICRP on which the fundame...Figure 13.2 The second triad of radiation protection is referred to as perso...Figure 13.3 The use of the OSL dosimeter involves at least three major steps...Figure 13.4 Three major steps involved when using the TLD: exposure to x‐ray...Figure 13.5 Factors that affect the thickness of protective barriers in radi...