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Oral radiography is a very important tool in veterinary medicine, however it is a widely underused and neglected commodity. The importance of its role in the optimal treatment of animals with oral and maxillofacial conditions, inc...
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Oral radiography is a very important tool in veterinary medicine, however it is a widely underused and neglected commodity. The importance of its role in the optimal treatment of animals with oral and maxillofacial conditions, including trauma and oncology cases, cannot be emphasised enough. A significant proportion of the pathological changes associated with oral disease processes are invisible to the naked eye as the tooth roots and alveolar bone are located subgingivally, therefore oral radiography is essential to facilitate a thorough assessment of their health and to identify underlying disease. Any practice admitting animals for 'dentals' are encouraged to invest in the equipment and training required to obtain diagnostic oral radiographs to enhance their treatment of these cases; this will be of benefit to the veterinary professionals involved with treating the animals, the clients and ultimately the patients.
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Objective: To compare proximal caries detection using intraoral bitewing, extraoral bitewing and panoramic radiography. Methods: 80 extracted human premolar and molar teeth with and without proximal caries were used. Intraoral rad...
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Objective: To compare proximal caries detection using intraoral bitewing, extraoral bitewing and panoramic radiography. Methods: 80 extracted human premolar and molar teeth with and without proximal caries were used. Intraoral radiographs were taken with Kodak Insight film (Eastman Kodak Co., Rochester, NY) using the bitewing technique. Extraoral bitewing and panoramic images were obtained using a Planmeca Promax Digital Panoramic X-ray unit (Planmeca Inc., Helsinki, Finland). Images were evaluated by three observers twice. In total, 160 proximal surfaces were assessed. Intra- and interobserver kappa coefficients were calculated. Scores obtained from the three techniques were compared with the histological gold standard using receiver operating characteristic analysis. Az values for each image type, observer and reading were compared using z-tests, with a significance level of a50.05. Results: Kappa coefficients ranged from 0.883 to 0.963 for the intraoral bitewing, from 0.715 to 0.893 for the extraoral bitewing, and from 0.659 to 0.884 for the panoramic radiography. Interobserver agreements for the first and second readings for the intraoral bitewing images were between 0.717 and 0.780, the extraoral bitewing readings were between 0.569 and 0.707, and the panoramic images were between 0.477 and 0.740. The Az values for both readings of all three observers were highest for the intraoral bitewing. Az values for the extraoral bitewing images were higher than those of the panoramic images without statistical significance (p>0.05). Conclusion: Intraoral bitewing radiography was superior to extraoral bitewing and panoramic radiography in diagnosing proximal caries of premolar and molar teeth ex vivo. Similar intra- and interobserver coefficients were calculated for extraoral bitewing and panoramic radiography.
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Radiologist are commonly required to compare a sequence of two or more chest radiographs of a given patient obtained over a period of time, which may range from a few hours to many years. In such cases, the task is one of detectin...
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Radiologist are commonly required to compare a sequence of two or more chest radiographs of a given patient obtained over a period of time, which may range from a few hours to many years. In such cases, the task is one of detecting interval change. In the case of patients who have had a previous chest radiograph, an opportunity exists to enhance selectively areas of interval change, including regions with new or altered pathology, by using the previous radiographs as a subtraction mask. With temporal subtraction, the previous image is superimposed and registered with the current image, using automated two-dimensional warping to compensate for any differences in positioning. A "difference image" is then created, by subtracting the previous from the current radiograph. In this temporal subtraction image, areas that are unchanged appear as uniform gray, while regions of new opacity, such as due to pneumonia or cancer, appear as prominent dark foci on a lighter background. By cancelling out the complex anatomical background, temporal subtraction can provide dramatically enhanced visibility of new areas of disease.
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Radiologist are commonly required to compare a sequence of two or more chest radiographs of a given patient obtained over a period of time, which may range from a few hours to many years. In such cases, the task is one of detectin...
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Radiologist are commonly required to compare a sequence of two or more chest radiographs of a given patient obtained over a period of time, which may range from a few hours to many years. In such cases, the task is one of detecting interval change. In the case of patients who have had a previous chest radiograph, an opportunity exists to enhance selectively areas of interval change, including regions with new or altered pathology, by using the previous radiographs as a subtraction mask. With temporal subtraction, the previous image is superimposed and registered with the current image, using automated two-dimensional warping to compensate for any differences in positioning. A "difference image" is then created, by subtracting the previous from the current radiograph. In this temporal subtraction image, areas that are unchanged appear as uniform gray, while regions of new opacity, such as due to pneumonia or cancer, appear as prominent dark foci on a lighter background. By cancelling out the complex anatomical background, temporal subtraction can provide dramatically enhanced visibility of new areas of disease.
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Since Roentgen's discovery of X rays in the late 1800s the use of penetrating radiation to form images has become a part of our everyday life as well as providing a useful tool for the scientific study of processes that have been ...
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Since Roentgen's discovery of X rays in the late 1800s the use of penetrating radiation to form images has become a part of our everyday life as well as providing a useful tool for the scientific study of processes that have been previously impossible to measure. This can include the study of processes that are too deeply embedded in opaque materials for direct observation, or that occur on a length or time scale smaller than otherwise can be easily measured. As technologies to generate penetrating radiation and quickly collect images have matured, new techniques have emerged to measure processes that have been hidden for many years. One example is advances in flash radiography using charged particles as radiographic probes, including proton radiography and electron radiography. Recently the successful commissioning of proton microscope systems has provided remarkable improvements in spatial resolution. These techniques are being implemented for applications with electron radiography. With the evolution of these new techniques comes the opportunity to choose the probe that provides the maximum information for the desired measurement. This paper describes these new imaging techniques, predicts the capabilities of high-energy electron radiography, and provides a guide for identifying the optimal probe for a wide range of measurements.
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Background and purpose: Radiographs are essential for detecting proximal caries. The aim of this study was to compare proximal caries detection using intra oral bitewing with film and digital bitewing. Materials and methods: Digit...
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Background and purpose: Radiographs are essential for detecting proximal caries. The aim of this study was to compare proximal caries detection using intra oral bitewing with film and digital bitewing. Materials and methods: Digital bitewing and conventional bitewing radiographs were taken from 100 extracted human teeth. Proximal caries depths in radiographs were scored by two oral and maxillofacial radiologists. Then the teeth were sectioned to evaluate and score the depth of caries lesions in proximal surfaces under microscope. Scores of radiographic and histopathologic assessments were compared using ROC curve analysis. Results: The differences of sensitivity and specificity of two techniques were not statistically significant. Conclusion: Accuracy of both radiographic techniques was found to be similar in this study.
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Introduction: Radiographers provide mobile radiography services for patients who are critically ill as well as patients isolated due to highly infectious diseases such as COVID-19. The pandemic has caused the demand for mobile rad...
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Introduction: Radiographers provide mobile radiography services for patients who are critically ill as well as patients isolated due to highly infectious diseases such as COVID-19. The pandemic has caused the demand for mobile radiography to increase. This study aims to understand the experience of radiographers performing mobile radiography during the COVID-19 pandemic to identify the success criteria and challenges faced. Methodology: This study utilized a cross sectional online survey to obtain data. The online survey was disseminated to radiographers working in public hospitals who have performed mobile radiography from February 2020 to September 2021. The key sections explored in the survey are: (1) demographics, (2) operations, (3) adequacy of resources, and (4) success criteria. The answers were obtained in the form of multiple choice questions, Likert scales or free text. Results: Radiographers reported a rise in mobile radiography workload as well as increased time required to perform an examination for COVID-19 patients. The factors identified for success criteria were: (1) infection control management, (2) resource management (3) modified techniques and (4) improved workflow. The challenges encountered were: (1) nature of exam, (2) juggling the demand for mobile imaging and (3) staff well-being. Conclusion: As the COVID-19 situation is evolving, departments have to constantly refine policies and processes as well as ensure the provision of adequate resources such as manpower and personal protective equipment (PPE) so that radiographers feel supported and can perform their duties safely.
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Pediatric projection imaging differs from imaging of the adult patient. Children are smaller, more radiosensitive, and less compliant than their adult counterparts. Their characteristics affect the way projection imaging is practi...
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Pediatric projection imaging differs from imaging of the adult patient. Children are smaller, more radiosensitive, and less compliant than their adult counterparts. Their characteristics affect the way projection imaging is practiced and how dose is optimized. Computed radiography (CR) and digital radiography (DR) have been embraced by pediatric practitioners in order to reduce dose and improve image quality. Unfortunately, dose optimization with CR and DR has been hampered by a lack of definition of appropriate exposure levels, a lack of standardization in exposure factor feedback, and a lack of understanding of the fundamentals of CR and DR technology. The potential for over-exposure exists with both CR and DR. Both the Society for Pediatric Radiology and the American Association of Physicists in Medicine recognize the promise and shortcomings of CR and DR technology and have taken steps to join with manufacturers in improving the practice of CR and DR imaging. Although the risks inherent in pediatric projection imaging with CR and DR are low, efforts to reduce dose are worthwhile, so long as diagnostic quality is maintained. Long-standing recommendations for limiting radiation dose in pediatric projection imaging are still applicable to CR and DR.
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Pediatric projection imaging differs from imaging of the adult patient. Children are smaller, more radiosensitive, and less compliant than their adult counterparts. Their characteristics affect the way projection imaging is practi...
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Pediatric projection imaging differs from imaging of the adult patient. Children are smaller, more radiosensitive, and less compliant than their adult counterparts. Their characteristics affect the way projection imaging is practiced and how dose is optimized. Computed radiography (CR) and digital radiography (DR) have been embraced by pediatric practitioners in order to reduce dose and improve image quality. Unfortunately, dose optimization with CR and DR has been hampered by a lack of definition of appropriate exposure levels, a lack of standardization in exposure factor feedback, and a lack of understanding of the fundamentals of CR and DR technology. The potential for over-exposure exists with both CR and DR. Both the Society for Pediatric Radiology and the American Association of Physicists in Medicine recognize the promise and shortcomings of CR and DR technology and have taken steps to join with manufacturers in improving the practice of CR and DR imaging. Although the risks inherent in pediatric projection imaging with CR and DR are low, efforts to reduce dose are worthwhile, so long as diagnostic quality is maintained. Long-standing recommendations for limiting radiation dose in pediatric projection imaging are still applicable to CR and DR.
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Protons were first investigated as radiographic probes as high energy proton accelerators became accessible to the scientific community in the 1960s. Like the initial use of X-rays in the 1800s, protons were shown to be a useful t...
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Protons were first investigated as radiographic probes as high energy proton accelerators became accessible to the scientific community in the 1960s. Like the initial use of X-rays in the 1800s, protons were shown to be a useful tool for studying the contents of opaque materials, but the electromagnetic charge of the protons opened up a new set of interaction processes which complicated their use. These complications in combination with the high expense of generating protons with energies high enough to penetrate typical objects resulted in proton radiography becoming a novelty, demonstrated at accelerator facilities, but not utilized to their full potential until the 1990s at Los Alamos. During this time Los Alamos National Laboratory was investigating a wide range of options, including X-rays and neutrons, as the next generation of probes to be used for thick object flash radiography. During this process it was realized that the charge nature of the protons, which was the source of the initial difficulty with this idea, could be used to recover this technique. By introducing a magnetic imaging lens downstream of the object to be radiographed, the blur resulting from scattering within the object could be focused out of the measurements, dramatically improving the resolution of proton radiography of thick systems. Imaging systems were quickly developed and combined with the temporal structure of a proton beam generated by a linear accelerator, providing a unique flash radiography capability for measurements at Los Alamos National Laboratory. This technique has now been employed at LANSCE for two decades and has been adopted around the world as the premier flash radiography technique for the study of dynamic material properties.
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