Globally there is a lack of radiologists, which results in unreported radiographic examinations, or a delay in reporting on radiographic images even in emergency situations. In order to mitigate and alleviate the situation, and optimise the utilisation of radiographers a red dot system was introduced in the United Kingdom, which later aided in the transformation of the role of radiographers in terms of formal reporting of various radiographic examinations. Although there is a shortage of medical practitioners and radiologists in South Africa the extended role of radiographers has not been yet realised for radiographers. At present, radiographers and medical practitioners work in collaboration to interpret and report on radiographic examinations informally, to facilitate effective and efficient patient management, but this is done illegally because the regulations defining the scope of the profession of radiography does not allow for such practice, putting radiographers and organisations at risk of litigation. In order to gain an in-depth knowledge of the phenomena, to enable the researcher to provide recommendations to the Professional Board of Radiography and Clinical Technology (PBRCT) of the Health Professions Council of South Africa (HPCSA), a qualitative, exploratory, descriptive, and contextual research study was undertaken. Radiographers and medical practitioners were interviewed in order to elicit rich descriptions of their experiences regarding reporting of trauma related radiographic images in the after-hours trauma units. Data were gathered using in-depth semi-structured interviews, and the data were analysed using kesch’s method of thematic synthesis. Three themes emerged from the data, namely the challenges radiographers and medical practitioners face in the after-hours trauma units respectively, with regards to reporting of trauma related adiographs, and suggestions were proposed to optimize the participation of radiographers with regard to trauma related radiographs in these units. A thick description and literature control was done using quotes from participants. Measures to ensure trustworthiness and ethical research practices were also implemented. Thereafter, recommendations were put forward for the PBRCT of the HPCSA, using current literature and inferences made from the findings of the study.

The National Council of Radiation Protection and Measurements Report No. 49, originally issued on September 15, 1976, has been the primary design guide for diagnostic x-ray structural shielding in the United States. To further protect the public from various areas of medical radiation exposure, NCRP issued Report 116 in 1987 to decrease the public exposure limits. These new limits used in conjunction with NCRP 49 to determine shielding requirements for diagnostic radiological rooms can be shown to over-shield based on current technologies and protocols. This paper explores the NCRP conservative assumptions that physicists specifying barrier requirements for diagnostic x-ray facilities normally utilize. These evaluated assumptions, which are incorporated in the methodology and attenuation data presented in NCRP Report 49 formulas, include relatively high single kVp's, a "one size fits all" workload default, and the lack of attenuation factors by the patient, the wall, and the film. In essence, an analysis of the conservative nature of NCRP 49 is demonstrated. An example of Primary and Secondary Shielding Methodology utilizing NCRP 49 and NCRP 116 dose limits is provided as well as the cost factors associated with the results. These examples are further evaluated using a Monte Carlo software program. In addition, an analysis of actual current radiographic conditions in an imaging room is performed. This is done to determine first, the actual mA utilized for specific exams; secondly, the actual mA-min weekly workload; and thirdly, the tangible exams performed per week in small and large medical facilities. Based on the information and analysis presented, this paper concludes that the formulas for NCRP 49 and NCRP 116 need to be reexamined. Furthermore, this paper also demonstrates once again that NCRP 49, utilizing NCRP 116 dose limits is extremely conservative. / Graduation date: 2004

A Varian 4 MeV isocentric therapy accelerator has been modified to perform also as a CT scanner. The goal is to provide low cost computed tomography capability for use in radiotherapy. The system will have three principal uses. These are (i) to provide 2- and 3-dimensional maps of electron density distribution for CT assisted therapy planning, (ii) to aid in patient set up by providing sectional views of the treatment volume and high contrast scout-mode verification images and (iii) to provide a means for periodically checking the patients anatomical conformation against what was used to generate the original therapy plan. The treatment machine was modified by mounting an array of detectors on a frame bolted to the counter weight end of the gantry in such a manner as to define a 'third generation' CT Scanner geometry. The data gathering is controlled by a Z-80 based microcomputer system which transfers the x-ray transmission data to a general purpose PDP 11/34 for processing. There a series of calibration processes and a logarithmic conversion are performed to get projection data. After reordering the projection data to an equivalent parallel beam sinogram format a convolution algorithm is employed to construct the image from the equivalent parallel projection data. Results of phantom studies have shown a spatial resolution of 2.6 mm and an electron density discrimination of less than 1% which are sufficiently good for accurate therapy planning. Results also show that the system is linear to within the precision of our measurement (≈ .75%) over a wide range of electron densities corresponding to those found in body tissues. Animal and human images are also presented to demonstrate that the system's imaging capability is sufficient to allow the necessary visualization of anatomy.

This dissertation presents a contrast-enhancement algorithm called Artifact-Suppressed Adaptive Histogram Equalization (ASAHE). This algorithm was developed as part of a larger effort to replace the film radiographs currently used in radiology departments with digital images. Among the expected benefits of digital radiology are improved image management and greater diagnostic accuracy. Film radiographs record X-ray transmission data at high spatial resolution, and a wide dynamic range of signal. Current digital radiography systems record an image at reduced spatial resolution and with coarse sampling of the available dynamic range. These reductions have a negative impact on diagnostic accuracy. The contrast-enhancement algorithm presented in this dissertation is designed to boost diagnostic accuracy of radiologists using digital images. The ASAHE algorithm is an extension of an earlier technique called Adaptive Histogram Equalization (AHE). The AHE algorithm is unsuitable for chest radiographs because it over-enhances noise, and introduces boundary artifacts. The modifications incorporated in ASAHE suppress the artifacts and allow processing of chest radiographs. This dissertation describes the psychophysical methods used to evaluate the effects of processing algorithms on human observer performance. An experiment conducted with anthropomorphic phantoms and simulated nodules showed the ASAHE algorithm to be superior for human detection of nodules when compared to a computed radiography system's algorithm that is in current use. An experiment conducted using clinical images demonstrating pneumothoraces (partial lung collapse) indicated no difference in human observer accuracy when ASAHE images were compared to computed radiography images, but greater ease of diagnosis when ASAHE images were used. These results provide evidence to suggest that Artifact-Suppressed Adaptive Histogram Equalization can be effective in increasing diagnostic accuracy and efficiency.

Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: digital x-ray imaging; pixel size; scintillator. Includes bibliographical references (p. 57-59).

Thesis (M.S.)--University of Florida, 2002. / Title from title page of source document. Includes vita. Includes bibliographical references.

Thesis (M.Sc.(Hons.))--University of Western Sydney, Nepean, 1995. / "A thesis submitted in fulfilment of the requirements for the degree of Master of Science (Honours) in Physics at the University of Western Sydney, Nepean" -- T.p. Bibliography: leaves 123-128.

Thesis (Ph.D.)--Mississippi State University. Department of Electrical and Computer Engineering. / Title from title screen. Includes bibliographical references.

Thesis (MTech (Radiography))--Peninsula Technikon, Cape Town, 2003 / Brain Compatible Learning (BCL), as its name suggests, is a type of learning which is aligned with how the human brain naturally learns and develops. BCL offers many different options and routes to learning as alternatives to conventional 'chalk and talk' methodologies. A BCL curriculum is planned to define the structure and content of a programme of learning, but it also provides opportunities for students to participate in activities, which encourage and enhance the development of an active and deep approach to learning. Using BCL approaches in the classroom thus creates both a stimulating and a caring environment for student learning. This project researches a BCL intervention in a Radiation Science course. The use of BCL techniques has tended to have been done predominantly in the social sciences; this research fills an important 'gap' in the research literature by examining how BCL might be implemented in a technical and scientific context. The research was conducted using an adapted Participatory Active Research methodology in which classroom interventions were planned (within a constructive framework), rather than implemented and then reflected on by all participants. The PAR method was supplemented with a series of detailed questionnaires and interviews. The broad findings of this study relate to students' experiences of BCL in Radiation Science in terms of 'process' and 'product" issues. In terms of process, or the methodology of BCL, students' responses were largely positive.

Thesis (DTech (Radiology))--Cape Peninsula University of Technology, 2016. / The aim of this study was to provide evidence basedforecast for radiology demand in Zimbabwe that would support policies aimed at optimising radiology resource allocation and utilisation. This was upon the realisation that the Ministry of Health and Childcare required such forecast in order to ensure equitable, accessible and quality health services as prescribed in the 2009-2015 National Health Strategy as well as in Section 29 and 76 of the Zimbabwean constitution. On the international perspective, many researchers have reported stable high demand for radiology services giving rise to long waiting lists and backlogs. In the United Kingdom’s National Health Services (NHS), there is general consensus that these waiting lists are caused by variation mismatches between capacity and demand for radiology services. Elsewhere, it has been reported that skill mix, role changes, dynamic nature of radiography teaching and learning, technology diffusion, service transaction time, overutilisation, and unjustified exposures are key drivers of high demand for radiology services. It has long been established that demand for radiology services is stochastic in nature, and therefore planning of future investments in radiology must be guided by an understanding of how these variables interact to model the criterion variable. However, there is paucity of information pertaining to key aspects of legitimate radiology demand forecasts. Formulation of these fundamental concepts formed the impetus of this study. A document review, interviews and non-participatory observations revealed that justification of radiology examinations, dynamic nature of radiography teaching and learning, diffusion of extended roles and technology, equipment and personnel capacity, and most importantly service transaction time all had an impact on the demand for radiology services in Zimbabwe. Limited diffusion of extended roles and technology had increased over a ten year period. Observed role changes were informal additions to the procedures normally carried out by radiographers and these were not supported by formal education. Consistent with global concerns, over utilisation and unjustified requests were a national concern. In situations where capacity outweighed demand, there was evidence that internal management of radiology departments was responsible for most variation mismatches which then gave rise to long waiting times.