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Digital radiography has evolved and co-existed with the dental imaging since four decades. The complete replacement of digital imaging in place of conventional screen-film combination has proved to be beneficial to the new era of dentistry. Because of low cost, higher patient comfort, increased dose efficiency, and greater dynamic range of digital detectors with possible reduction of radiation exposure to the patient, the digital imaging has created a new place for itself not only in medical radiology but in dentistry as well. The future will be digital, irrespective of CCDs, CMOS, or phosphor plates the advancement in the field of imaging is rapid and progressive with constantly replacing the older ones. The present paper discusses thoroughly about the various advancements in digital imaging starting from CCDs to flexible phosphor plates. Digital imaging, a substitute for conventional film radiography, has ventured into the arena of dentistry as well and revolutionised the imaging concepts of Oral Health Care Professionals.
ABSTRACT
Objetivo: Avaliar a dose glandular média utilizando um detector de estado sólido e a qualidade da imagem de um sistema de radiografia direta a partir de objetos simuladores. Materiais e Métodos: Irradiações foram realizadas utilizando o controle automático de exposição e placas de polimetilmetacrilato com diferentes espessuras para o cálculo da dose glandular média. A qualidade da imagem foi avaliada por meio das estruturas visualizadas nas imagens dos objetos simuladores. Resultados: Considerando a incerteza das medições, os resultados de dose glandular média estão de acordo com os valores fornecidos pelo equipamento e com os níveis de referência adotados internacionalmente. Os resultados obtidos a partir das imagens dos objetos simuladores estavam em conformidade com os valores de referência. Conclusão: Este trabalho contribui para verificar a conformidade do equipamento em relação a dose e qualidade da imagem. .
Objective: To evaluate the mean glandular dose with a solid state detector and the image quality in a direct radiography system, utilizing phantoms. Materials and Methods: Irradiations were performed with automatic exposure control and polymethyl methacrylate slabs with different thicknesses to calculate glandular dose values. The image quality was evaluated by means of the structures visualized on the images of the phantoms. Results: Considering the uncertainty of the measurements, the mean glandular dose results are in agreement with the values provided by the equipment and with internationally adopted reference levels. Results obtained from images of the phantoms were in agreement with the reference values. Conclusion: The present study contributes to verify the equipment conformity as regards dose values and image quality. .
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BACKGROUND: This study examined the clinical utility of using indirect chest radiography during a physical examination of new conscripts for determine the presence of pulmonary tuberculosis. METHOD: Over an eight-month period, this study examined 25386 people who underwent a physical examination after conscription. The abnormal findings on mass miniature radiography were followed-up using direct chest radiography. The positive predictive value of mass miniature radiography and direct chest radiography was compared. The incidence, degree of infiltration and clinical outcome of active pulmonary tuberculosis were also evaluated during a follow-up examination. RESULTS: The positive rate of mass miniature radiography was 1.19% (n=302). Various lesions were identified: Parenchymal lesions (n=109), mediastinal lesions (n=6), cardiovascular lesions (n=45), pleural lesions (n=49), bony lesions (n=90) and miscellaneous lesions (n=7). The incidence of active pulmonary tuberculosis by mass miniature radiography was 0.26% (n=67). The first diagnosis was made in 50 people; active pulmonary tuberculosis (n=42), pneumonia (n=1), a mediastinal mass (n=1), a rib fracture (n=2) and a pneumothorax (n=4). Most cases of active pulmonary tuberculosis were mildly infiltrated and either improved or were cured by the follow-up examination. CONCLUSION: Although mass miniature radiography in a physical examination after conscription has limitations, but it is a useful means for detecting the presence of early disease, particularly in active pulmonary tuberculosis.
Subject(s)
Diagnosis , Follow-Up Studies , Incidence , Mass Screening , Physical Examination , Pneumonia , Pneumothorax , Radiography , Rib Fractures , Thorax , Tuberculosis, PulmonaryABSTRACT
Objective To evaluate the Imaging diagnosis of SARS in death case.Methods 11 death patients of SARS in keeping with criteria from April to May 2003 were enrolled into the study. Imaging characteristics of chest x-ray film and CT in these patients were analysed.Results All cases were positive on chest X-ray film and CT,the lung shadows were marked.The extent of the pathological changes in lungs was 80%～90% in 6 cases and 90% above in 5 cases,multilobcs of bilateral lungs were involved in all cases.The lesions were diffuse spotty shadow or shaggy cloudy shadow in 8 cases,ground-glass opacification in one case and bronchogram structures could be seen.Conclusion Imaging findings in the cases with severe SARS mostly manifest as effusion,consolidation and interstitial inflammation in multilobes of bilateral lungs.