Download or read book Optimizing of Dose and Imaging Quality for Computer and Digital Radhiography written by Zubir Ahmad Shazli and published by IIUM PRESS. This book was released on 2021-04-01 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimization of dose in radiographic examinations is essential since the utilization of x-radiation is related to increased cancer risk. The study’s objective was to guide radiographers in ensuring best practices for common radiographic examinations of acceptable image quality in digital radiography while minimizing radiation doses that could result in harmful effects. The study comprised of three phases. The first phase involved 90 respondents between 20 to 60 years of age and weighing between 60-80 kilograms for the following examinations: anterior-posterior (AP) abdomen, AP or lateral lumbar sacral spine and posterior-anterior (PA) chest examinations. During this phase, the radiographic examination’s technical parameters for 30 radiographs for each examination were at the radiographers’ discretion. Kerma X_plus, DAP (dose area product) meter was utilized to evaluate the entrance surface dose (ESD), while CALDose_X 5.0 Monte Carlo was used to estimate the effective dose. The experimental study utilized an anthropomorphic phantom (PBU-50) and Leeds test object to compare the image quality. The best parameters were adapted to the patient’s AP thickness for the optimization study from the different technical parameters used in the experimental phase.

Download or read book Assessment and Optimisation of Digital Radiography Systems for Clinical Use written by Philip Doyle and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Digital imaging has long been available in radiology in the form of computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound. Initially the transition to general radiography was slow and fragmented but in the last 10-15 years in particular, huge investment by the manufacturers, greater and cheaper computing power, inexpensive digital storage and high bandwidth data transfer networks have lead to an enormous increase in the number of digital radiography systems in the UK. There are a number of competing digital radiography (DR) technologies, the most common are computer radiography (CR) systems followed by indirect digital radiography (IDR) systems. To ensure and maintain diagnostic quality and effectiveness in the radiology department appropriate methods are required to evaluate and optimise the performance of DR systems. Current semi-quantitative test object based methods routinely used to examine DR performance suffer known short comings, mainly due to the subjective nature of the test results and difficulty in maintaining a constant decision threshold among observers with time. Objective image quality based measurements of noise power spectra (NPS) and modulation transfer function (MTF) are the 'gold standard' for assessing image quality. Advantages these metrics afford are due to their objective nature, the comprehensive noise analysis they permit and in the fact that they have been reported to be relatively more sensitive to changes in detector performance. The advent of DR systems and access to digital image data has opened up new opportunities in applying such measurements to routine quality control and this project initially focuses on obtaining NPS and MTF results for 12 IDR systems in routine clinical use. Appropriate automatic exposure control (AEC) device calibration and a reproducible measurement method are key to optimising X-ray equipment for digital radiography. The uses of various parameters to calibrate AEC devices specifically for DR were explored in the next part of the project and calibration methods recommended. Practical advice on dosemeter selection, measurement technique and phantoms were also given. A model was developed as part of the project to simulate CNR to optimise beam quality for chest radiography with an IDR system. The values were simulated for a chest phantom and adjusted to describe the performance of the system by inputting data on phosphor sensitivity, the signal transfer function (STF), the scatter removal method and the automatic exposure control (AEC) responses. The simulated values showed good agreement with empirical data measured from images of the phantom and so provide validation of the calculation methodology. It was then possible to apply the calculation technique to imaging of tissues to investigate optimisation of exposure parameters. The behaviour of a range of imaging phosphors in terms of energy response and variation in CNR with tube potential and various filtration options were investigated. Optimum exposure factors were presented in terms of kV-mAs regulation curves and the large dose savings achieved using additional metal filters were emphasised. Optimum tube potentials for imaging a simulated lesion in patient equivalent thicknesses of water ranging from 5-40 cm thick for example were: 90-110kVp for CsI (IDR); 80-100kVp for Gd2O2S (screen /film); and 65-85kVp for BaFBrI. Plots of CNR values allowed useful conclusions regarding the expected clinical operation of the various DR phosphors. For example 80-90 kVp was appropriate for maintaining image quality over an entire chest radiograph in CR whereas higher tube potentials of 100-110 kVp were indicated for the CsI IDR system. Better image quality is achievable for pelvic radiographs at lower tube potentials for the majority of detectors however, for gadolinium oxysulphide 70-80 kVp gives the best image quality. The relative phosphor sensitivity and energy response with tube potential were also calculated for a range of DR phosphors. Caesium iodide image receptors were significantly more sensitive than the other systems. The percentage relative sensitivities of the image receptors averaged over the diagnostic kV range were used to provide a method of indicating what the likely clinically operational dose levels would be, for example results suggested 1.8 μGy for CsI (IDR); 2.8 μGy for Gd2O2S (Screen/film); and 3.8 μGy for BaFBrI (CR). The efficiency of scatter reduction methods for DR using a range of grids and air gaps were also reviewed. The performance of various scatter reduction methods: 17/70; 15/80; 8/40 Pb grids and 15 cm and 20 cm air gaps were evaluated in terms of the improvement in CNR they afford, using two different models. The first, simpler model assumed quantum noise only and a photon counting detector. The second model incorporated quantum noise and system noise for a specific CsI detector and assumed the detector was energy integrating. Both models allowed the same general conclusions and suggest improved performance for air gaps over grids for medium to low scatter factors and both models suggest the best choice of grid for digital systems is the 15/80 grid, achieving comparable or better performance than air gaps for high scatter factors. The development, analysis and discussion of AEC calibration, CNR value, phosphor energy response, and scatter reduction methods are then brought together to form a practical step by step recipe that may be followed to optimise digital technology for clinical use. Finally, CNR results suggest the addition of 0.2 mm of copper filtration will have a negligible effect on image quality in DR. A comprehensive study examining the effect of copper filtration on image quality was performed using receiver operator characteristic (ROC) methodology to include observer performance in the analysis. A total of 3,600 observations from 80 radiographs and 3 observers were analysed to provide a confidence interval of 95% in detecting differences in image quality. There was no statistical difference found when 0.2 mm copper filtration was used and the benefit of the dose saving promote it as a valuable optimisation tool.

Download or read book Digital Radiography written by Euclid Seeram and published by Cengage Learning. This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Digital Radiography: An Introduction for Technologists, presents the physical principles and technical description of digital radiography imaging systems and associated technologies. This book functions as both a primary source for introductory digital imaging courses and as a reference for radiologic technologists and other imaging personnel. The book begins by exploring the many digital image acquisition imaging modalities such as computed radiography (CR), flat-panel digital radiography, digital fluoroscopy, and digital mammography systems in detail, followed by an outline of the essential elements of digital image processing. Associated technologies such as picture archiving and communication systems (PACS) and medical imaging informatics (MII) are also outlined. Finally, the book concludes with a description of quality control procedures for digital radiography.

Download or read book Optimisation of Dose and Performance in Interventional and Digital Imaging written by K. Faulkner and published by . This book was released on 2005 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Image Optimization in Digital Dental Radiography written by Kelli J. Silverstrim and published by . This book was released on 2014 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: When the United States Air Force completed a multi-million dollar transition to digital dental radiography in 2010 there was no quantitative method available for establishing the appropriate balance of image quality and radiation dose. The objective of this research was to devise a process to fill this need. Through computer simulation and clinical validation the effect of technical parameters on digital dental radiographic image quality was investigated and an optimization method was devised. The Monte Carlo N-Particle Extended (MCNPX) radiation transport code was used to model the DC Planmeca Intra and AC Gendex 770 dental intraoral radiographic units and a unique anthropomorphic phantom simulating dental bitewing anatomy. The Carestream 6100 RVG sensor signal response, noise response, dose rate dependence and reproducibility were determined experimentally, as were their uncertainties and the inter- and intra- radiographic unit variabilities. The experimental measurements were used to calibrate and scale the MCNPX generated data for the optimization analysis. The technical parameters modified in the simulation were peak kilovoltage, (50 through 90) and tube filtration (inherent, 0.1 mm and 0.2 mm added copper). The entrance air KERMA (~720 microGy) at the current clinical technique (63 kVp at 1 milliAmpere-seconds) was used to establish the reference image quality metrics for comparison. Four figures of merit (FOM) were chosen to encompass the impact of variations in the adjustable parameters. With equal weighting of all FOMs and given no limitations on the equipment, the optimal combination of kVp and tube filtration for dental bitewing imaging identified was 90 kVp with 0.1 mm added copper filtration. The optimal technique in the radiographic units' operating range was 70 kVp and 0.1 mm added copper filtration, which could be immediately adopted for a ~50% (+/-17%) entrance dose and ~40% effective dose savings (Planmeca units). In general, the optimization method facilitates image quality standardization across different radiographic units and sensors in a dental clinic. The unique computer model and optimization method used could be easily customized to evaluate any adult or pediatric intraoral imaging task. The results underscore the importance of tailoring the technical parameters to the particular imaging devices in service.

Download or read book Dose Optimization in Digital Radiography and Computed Tomography written by Euclid Seeram and published by Springer Nature. This book was released on 2023-02-21 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses radiation protection of patients having digital radiography and computed tomography (CT) examinations. The literature on radiation doses to patients from these two modalities have reported that the doses to patients are high. As a result, the radiology community has focused on methods and procedures to keep these doses as low as reasonably achievable (ALARA) without compromising the diagnostic image quality. This book outlines the motivation for dose optimization in radiology, identifies and describes the ICRP principle of optimization, outlines the factors affecting the dose in digital radiography and in CT, and identifies and describes strategies used in digital radiography and in CT for dose optimization. This book is intended for all those working in digital radiography and CT environments including radiological technologists, and radiographers, radiologists, biomedical engineering technologists, and student medical physicists. It is best used as a supplement to radiologic science textbooks, and in particular, radiation protection textbooks. Furthermore, this book lays the foundations for students and practitioners engaged in research on dose reduction and dose optimization in radiology. · Provides practical and useful methods for optimization of doses from digital radiography and CT · Describes the International Commission on Radiological Protection (ICRP) principle of optimization · Outlines the factors affecting the dose in digital radiography and in computed tomography

Download or read book Optimization of Image Quality and Minimization of Radiation Dose for Chest Computed Radiography written by Xiang Kong and published by . This book was released on 2006 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Computer Assisted Radiology Computergest tzte Radiologie written by AMK Berlin and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 721 pages. Available in PDF, EPUB and Kindle. Book excerpt: New imaging technology and more sophisticated image processing systems will have a profound effect on those areas of medicine which are concerned with imaging for diagnosis and therapy planning. Digitally formated data will form the basis of an increasing number of medical imaging modalities. Before the diagnostic imaging department of the future will largely be digital, many problems have still to be solved as regards image quality, costs, and ease of use. The computer and other information science derived methods will contribute towards solving many of the problems in these areas. It is widely expected that there will be an information science derived evolution in imaging for radiology and related departments. Computer assistance may be applied to image generation, e.g. CT, MRI, DR and DSR, storing and transferring of images, and viewing, analysing and interpreting of images. The application of computers to these activities (which characterise radiological departments), may be defined as Computer Assisted Radiology (CAR) . In the main, CAR will promote the transition from analog imaging systems to digital systems, integration of digital imaging modalities through Picture Archiving and Communication Systems (PACS') and the graduated employment of Medica~ Work Stations (MWS) for diagnosis and therapy planning. It will transfer geographically, organisationally and/or mentally isolate imaging activities towards fully integrated multi-imaging modality diagnostic departments. This development will have a considerable impact on patient management, on the medical profession and on the health care system.

Download or read book Digital Imaging Systems for Plain Radiography written by Luis Lanca and published by Springer Science & Business Media. This book was released on 2012-10-25 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in digital technology led to the development of digital x-ray detectors that are currently in wide use for projection radiography, including Computed Radiography (CR) and Digital Radiography (DR). Digital Imaging Systems for Plain Radiography addresses the current technological methods available to medical imaging professionals to ensure the optimization of the radiological process concerning image quality and reduction of patient exposure. Based on extensive research by the authors and reference to the current literature, the book addresses how exposure parameters influence the diagnostic quality in digital systems, what the current acceptable radiation doses are for useful diagnostic images, and at what level the dose could be reduced to maintain an accurate diagnosis. The book is a valuable resource for both students learning the field and for imaging professionals to apply to their own practice while performing radiological examinations with digital systems.

Download or read book Digital Mammography written by Ulrich Bick and published by Springer Science & Business Media. This book was released on 2010-03-11 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Digital Radiography has been ? rmly established in diagnostic radiology during the last decade. Because of the special requirements of high contrast and spatial resolution needed for roentgen mammography, it took some more time to develop digital m- mography as a routine radiological tool. Recent technological progress in detector and screen design as well as increased ex- rience with computer applications for image processing have now enabled Digital Mammography to become a mature modality that opens new perspectives for the diag- sis of breast diseases. The editors of this timely new volume Prof. Dr. U. Bick and Dr. F. Diekmann, both well-known international leaders in breast imaging, have for many years been very active in the frontiers of theoretical and translational clinical research, needed to bring digital mammography ? nally into the sphere of daily clinical radiology. I am very much indebted to the editors as well as to the other internationally rec- nized experts in the ? eld for their outstanding state of the art contributions to this v- ume. It is indeed an excellent handbook that covers in depth all aspects of Digital Mammography and thus further enriches our book series Medical Radiology. The highly informative text as well as the numerous well-chosen superb illustrations will enable certi? ed radiologists as well as radiologists in training to deepen their knowledge in modern breast imaging.

Download or read book Optimization of Image Quality and Patient Exposure in Diagnostic Radiology written by B. M. Moores and published by . This book was released on 1989 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: A concise review of the overall framework for quality control in diagnostic radiology including clinical, scientific and technical requirements. These are the proceedings of a workshop organized by the Commission of the European Communities and National Radiological Protection Board.

Download or read book Digital Radiography written by William R. Brody and published by Lippincott Williams & Wilkins. This book was released on 1984 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiation Exposure and Image Quality in X Ray Diagnostic Radiology written by Horst Aichinger and published by Springer Science & Business Media. This book was released on 2011-10-25 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: This completely updated second edition of Radiation Exposure and Image Quality in X-ray Diagnostic Radiology provides the reader with detailed guidance on the optimization of radiological imaging. The basic physical principles of diagnostic radiology are first presented in detail, and their application to clinical problems is then carefully explored. The final section is a supplement containing tables of data and graphical depictions of X-ray spectra, interaction coefficients, characteristics of X-ray beams, and other aspects relevant to patient dose calculations. In addition, a complementary CD-ROM contains a user-friendly Excel file database covering these aspects that can be used in the reader’s own programs. This book will be an invaluable aid to medical physicists when performing calculations relating to patient dose and image quality, and will also prove useful for diagnostic radiologists and engineers.

Download or read book Optimisation of Image Quality and Patient Dose for Chest Radiography with Digital Radiographic Systems written by Ana Isabel Lourenço Pascoal and published by . This book was released on 2006 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Computer Assisted Radiology Computergest tzte Radiologie written by Heinz U. Lemke and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 835 pages. Available in PDF, EPUB and Kindle. Book excerpt: CAR is a symposium and exhibition covering the impact of computer and communication systems applied to radiology and other medical disciplines, which use digital imaging for diagnosis and therapy planning. CAR '93 also provides tutorials, but more emphasis is given to a broad variety of specific problems related to medical/technical issues in digital imaging. This is achieved through in-depth presentations of results of current medical imaging projects on a worldwide basis.

Download or read book Diagnostic Radiology Physics written by International Atomic Energy Agency and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication is aimed at students and teachers involved in programmes that train medical physicists for work in diagnostic radiology. It provides a comprehensive overview of the basic medical physics knowledge required in the form of a syllabus for the practice of modern diagnostic radiology. This makes it particularly useful for graduate students and residents in medical physics programmes. The material presented in the publication has been endorsed by the major international organizations and is the foundation for academic and clinical courses in both diagnostic radiology physics and in emerging areas such as imaging in radiotherapy.

Download or read book Digital Radiography written by Euclid Seeram and published by Springer. This book was released on 2019-01-23 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the second edition of a well-received book that enriches the understanding of radiographers and radiologic technologists across the globe, and is designed to meet the needs of courses (units) on radiographic imaging equipment, procedures, production, and exposure. The book also serves as a supplement for courses that address digital imaging techniques, such as radiologic physics, radiographic equipment and quality control. In a broader sense, the purpose of the book is to meet readers’ needs in connection with the change from film-based imaging to film-less or digital imaging; today, all radiographic imaging worldwide is based on digital imaging technologies. The book covers a wide range of topics to address the needs of members of various professional radiologic technology associations, such as the American Society of Radiologic Technologists, the Canadian Association of Medical Radiation Technologists, the College of Radiographers in the UK, and the Australian and New Zealand Societies for Radiographers.