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Michael D Attfield - One of the best experts on this subject based on the ideXlab platform.
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intramodality and intermodality comparisons of storage phosphor computed radiography and conventional film screen radiography in the recognition of small pneumoconiotic opacities
Chest, 2011Co-Authors: Scott A Laney, Edward L Petsonk, Michael D AttfieldAbstract:Background Digital radiography systems are replacing traditional film for chest radiographic monitoring in the recognition of pneumoconiosis. Methods To further investigate previous findings regarding the equivalence of film-screen radiographs (FSRs) and storage phosphor computed radiographs (CRs), FSRs and CRs from 172 underground coal miners were classified independently by seven National Institute for Occupational Safety and Health-approved B readers, using the International Labor Office (ILO) Classification of radiographs of pneumoconiosis. Results More CRs were classified as “good” quality compared with FSRs (prevalence ratio [PR], 1.5; 95% CI, 1.4-1.6; P , .001). B readers showed good overall agreement on scoring small opacity profusion using CRs vs FSRs (weighted κ, 0.58; 95% CI, 0.54-0.62). Significantly more irregular opacities (compared with rounded) were classified using CR images compared with FSR (PR, 1.3; 95% CI, 1.1-1.6; P = .01). Similarly, the smallest sized opacities (width P Conclusions Under optimal conditions, using standardized methods and equipment, reader visualization of small pneumoconiotic opacities does not appear to differ meaningfully, whether using CR or FSR. Variability in ILO Classifications between imaging modalities appears to be considerably lower than variability among readers. The well-documented challenge of reader variability does not appear to be resolved through the use of digital imaging alone, and additional approaches must be evaluated.
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comparison of storage phosphor computed radiography with conventional film screen radiography in the recognition of pneumoconiosis
European Respiratory Journal, 2010Co-Authors: A S Laney, Edward L Petsonk, Anita L Wolfe, Michael D AttfieldAbstract:Traditional film-screen radiography (FSR) has been useful in the recognition and evaluation of interstitial lung diseases, but is becoming increasingly obsolete. To evaluate the applicability of storage phosphor digital computed radiography (CR) images in the recognition of small lung opacities, we compared image quality and the profusion of small opacities between FSR and CR radiographs. We screened 1,388 working coal miners during the course of the study with FSR and CR images obtained on the same day from all participants. Each traditional chest film was independently interpreted by two of eight experienced readers using the International Labour Office (ILO) Classification of radiographs of pneumoconiosis, as were CR images displayed on medical-grade computer monitors. The prevalence of small opacities (ILO category 1/0 or greater) did not differ between the two imaging modalities (5.2% for FSR and 4.8% for soft copy CR; p>0.50). Inter-reader agreement was also similar between FSR and CR. Significant differences between image modalities were observed in the shape of small opacities, and in the proportion of miners demonstrating high opacity profusion (category 2/1 and above). Our results indicate that, with appropriate attention to image acquisition and soft copy display, CR digital radiography can be equivalent to FSR in the identification of small interstitial lung opacities.
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exposure to silica and silicosis among tin miners in china exposure response analyses and risk assessment
Occupational and Environmental Medicine, 2001Co-Authors: Weihong Chen, Z Zhuang, Michael D Attfield, B T Chen, Pi Gao, Joel C Harrison, Jq Chen, William E WallaceAbstract:Objectives—To investigate the risk of silicosis among tin miners and to investigate the relation between silicosis and cumulative exposure to dust (Chinese total dust and respirable crystalline silica dust). Methods—A cohort study of 3010 miners exposed to silica dust and employed for at least 1 year during 1960‐5 in any of four Chinese tin mines was conducted.Historical total dust data from China were used to create a job exposure matrix for facility, job title, and calendar year. The total dust exposure data from China were converted to estimates of exposure to respirable crystalline silica for comparison with findings from other epidemiological studies of silicosis. Each worker’s work history was abstracted from the complete employment records in mine files. Diagnoses of silicosis were based on 1986 Chinese pneumoconiosis Roentgen diagnostic criteria, which classified silicosis as stages I-III—similar to an International Labour Organisation (ILO) Classification of 1/1 or greater. Results—There were 1015 (33.7%) miners identified with silicosis, who had a mean age of 48.3 years, with a mean of 21.3 years after first exposure (equivalent to 11.0 net years in a dusty job). Among those who had silicosis, 684 miners (67.4%) developed silicosis after exposure ended (a mean of 3.7 years after). The risk of silicosis was strongly related to cumulative exposure to silica dust and was well fitted by the Weibull distribution, with the risk of silicosis less than 0.1% when the Chinese measure of cumulative exposure to total dust (CTD) was under 10 mg/m 3
Clifford Panter - One of the best experts on this subject based on the ideXlab platform.
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prevalence of occupational lung disease in a random sample of former mineworkers libode district eastern cape province south africa
American Journal of Industrial Medicine, 1998Co-Authors: A S M Trapido, Richard Goode, Nokuzola P Mqoqi, Cecil Macheke, Anthony J Davies, Albert Solomon, Brian G. Williams, N White, Clifford PanterAbstract:Background Gold mineworkers in South Africa are exposed to high levels of silica dust as a result of which they are at risk of developing silicosis, which is a compensable disease. The incidence of tuberculosis is also high. Methods To determine the prevalence of occupational lung disease and the previous compensation history in former migrant mineworkers, a study was undertaken in a random sample of men living in Libode, a rural district of Eastern Cape Province, South Africa. Two hundred thirty-eight ex-mineworkers were examined according to a protocol that included chest radiography and spirometry. Chest radiographs were read into the International Labour Organisation (ILO) Classification for pneumoconioses by two readers. Results The mean age was 52.8 years, and the mean length of service was 12.15 years. The prevalence of pneumoconiosis (≥ILO 1/0) was 22% and 36% (variation by reader). For both readers, a significant association between length of service and pneumoconiosis and between pneumoconiosis and reduction in FVC and FEV was found. Twenty-four percent of study subjects were eligible for compensation. Conclusion There is a high prevalence of previously undiagnosed, uncompensated pneumoconiosis in the study group. As a result of the failure to diagnose and compensate occupational lung disease, the social and economic burden of such disease is being borne by individuals, households, and the migrant labor-sending communities as a whole. Am. J. Ind. Med. 34:305–313, 1998. © 1998 Wiley-Liss, Inc.
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prevalence of occupational lung disease in a random sample of former mineworkers libode district eastern cape province south africa
American Journal of Industrial Medicine, 1998Co-Authors: A S M Trapido, Richard Goode, Nokuzola P Mqoqi, Cecil Macheke, Anthony J Davies, Albert Solomon, Brian G. Williams, N White, Clifford PanterAbstract:Background Gold mineworkers in South Africa are exposed to high levels of silica dust as a result of which they are at risk of developing silicosis, which is a compensable disease. The incidence of tuberculosis is also high. Methods To determine the prevalence of occupational lung disease and the previous compensation history in former migrant mineworkers, a study was undertaken in a random sample of men living in Libode, a rural district of Eastern Cape Province, South Africa. Two hundred thirty-eight ex-mineworkers were examined according to a protocol that included chest radiography and spirometry. Chest radiographs were read into the International Labour Organisation (ILO) Classification for pneumoconioses by two readers. Results The mean age was 52.8 years, and the mean length of service was 12.15 years. The prevalence of pneumoconiosis (≥ILO 1/0) was 22% and 36% (variation by reader). For both readers, a significant association between length of service and pneumoconiosis and between pneumoconiosis and reduction in FVC and FEV was found. Twenty-four percent of study subjects were eligible for compensation. Conclusion There is a high prevalence of previously undiagnosed, uncompensated pneumoconiosis in the study group. As a result of the failure to diagnose and compensate occupational lung disease, the social and economic burden of such disease is being borne by individuals, households, and the migrant labor-sending communities as a whole. Am. J. Ind. Med. 34:305–313, 1998. © 1998 Wiley-Liss, Inc.
Atila Gokcek - One of the best experts on this subject based on the ideXlab platform.
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comparison of the international Classification of high resolution computed tomography for occupational and environmental respiratory diseases with the international labor organization international Classification of radiographs of pneumoconiosis
Industrial Health, 2019Co-Authors: Melahat Uzel şener, Ceprail şimşek, şeref Ozkara, Hale Evran, Ilke Bursali, Atila GokcekAbstract:The International Classification of High-resolution Computed Tomography for Occupational and Environmental Respiratory Diseases (ICOERD) has been developed for screening and diagnosis of occupational lung diseases. We evaluated the association of icoerd with the International Labor Organization (ILO) Classification and respiratory functions in pneumoconiosis. Chest x-rays of patients with pneumoconiosis were classified with ILO and icoerd using hrct, irregular opacity, pleural pathology, and emphysema was detected in 78, 19, and 53 patients, and using chest x-rays in 47, 4, and 14 patients, respectively. There was a significant correlation between ILO categories and ICOERD grades. There was a negative correlation between ILO categories and FEV1% and FVC%, whereas, ICOERD grades were not correlated with FEV1% and FVC%. HRCT was superior to chest x-rays to detect pneumoconiosis in early stage, but not in evaluating pulmonary functions.
Gavin J Churchyard - One of the best experts on this subject based on the ideXlab platform.
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predictors of silicosis and variation in prevalence across mines among employed gold miners in south africa
BMC Public Health, 2020Co-Authors: Dave Knight, Rodney Ehrlich, Annibale Cois, Katherine L Fielding, Alison D Grant, Gavin J ChurchyardAbstract:The stated intention to eliminate silicosis from the South African goldmining industry as well as current programmes to find and compensate ex-miners with silicosis require an understanding of variation in silicosis prevalence across the industry. We aimed to identify the predictors of radiological silicosis in a large sample of working miners across gold mines in South Africa. Routine surveillance chest radiographs were collected from 15 goldmine “clusters” in a baseline survey undertaken in preparation for a separate tuberculosis isoniazid prophylaxis trial. All images were read for silicosis by a health professional experienced in using the International Labour Organisation (ILO) Classification. Profusion thresholds of > 1/0 and > 1/1 were used. Demographic and occupational information was obtained by questionnaire. Predictors of silicosis were examined in a multivariable logistic regression model, including age, gender, racial ascription, country of origin, years since starting mine employment, mine shaft, skill category, underground work status and tuberculosis. The crude silicosis prevalence at ILO > 1/1 was 3.8% [95% confidence interval (CI) 3.5–4.1%]. The range across mine shafts was 0.8–6.9%. After adjustment for covariates, the interquartile range across shafts was reduced from 2.4 to 1.2%. Black miners [adjusted odds ratio (aOR) 2.8; 95% CI 1.1–7.2] and miners in full-time underground work (aOR 2.1; 95% CI 1.3–3.4) had substantially elevated odds of silicosis, while workers from Mozambique had lower odds (aOR 0.54; 95% CI 0.38–0.77). Silicosis odds rose sharply with both age and years since starting in the industry (p for linear trend 15 years since first exposure and 2.2% < 10 years. In surveillance of silicosis in working gold miners time since first exposure remains a powerful predictor. Age appears to be an independent predictor, while the detection of radiological silicosis in short-service miners requires attention. Public risk reporting by mines should include factors bearing on silicosis prevalence, specifically dust concentrations, with independent verification. Studies of silicosis and tuberculosis in ex-miners are needed, supported by an accessible electronic database of the relevant medical and dust exposure records of all gold miners.
Edward L Petsonk - One of the best experts on this subject based on the ideXlab platform.
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validation of the international labour office digitized standard images for recognition and Classification of radiographs of pneumoconiosis
Academic Radiology, 2014Co-Authors: Cara N Halldin, Edward L Petsonk, Scott A LaneyAbstract:Chest radiographs are recommended for the detection and prevention of pneumoconiosis in workers involved in dusty trades, such as underground mining (1). In clinical practice and public health surveillance, digital chest radiographs (DR) presented on medical-grade monitors have largely replaced the conventional film-screen radiograph (FSR) technology. The International Labour Office (ILO) Guidelines for the Classification of the Pneumoconioses has been an invaluable tool for standardization of interpretations of chest radiographs for epidemiologic studies of the pneumoconioses (2). To enhance accuracy and precision in applying the ILO Classification scoring system, readers are required to perform a side-by-side comparison of each individual worker’s radiograph to one or more prototypical chest images, which illustrate a variety of types and severity of radiographic abnormalities induced by dust inhalation. The ILO Classification system includes a standard set of chest images for comparison purposes. Until recently, the ILO Classification system only provided a set of standard images in the film-screen radiograph (FSR) format. However, in 2011, the ILO revised its guidelines to “extend the applicability of the Classification to digital radiographic images of the chest” (2). In the 2011 revision of the Classification, the ILO includes a set of electronic image files (ILO Standard Digital Images [2011-D]) that was digitized from the film-based standards included in the 2000 revision of the Classification. Prior to the adoption of the ILO Standard Digital Images (2011-D), a series of research studies was undertaken to assess any potential impact of image modality on the outcomes of ILO Classifications of chest radiographs (comparing FSR to DR displayed on medical-grade diagnostic monitors) (1,3–5). These investigations obtained both FSR and DR chest radiographs from study participants on the same day. FSR chest radiographs were interpreted using the ILO 2000 version of the Classification system with the traditional film-based standard images. To enable Classification of the DR chest radiographs displayed as soft copies on a medical-grade computer monitor, an existing set of the ILO standard films was scanned and digitized (see Franzblau et al. (3) for methods). The resulting image files (“research” digitized standards) were used as the ILO standards for classifying digital images in a number of previous investigations (3–6). These “research” digitized standards appear quite similar to the current set of standard films that are included in the ILO 2000 Classification, but were digitized from a prior version of the ILO standard films that had been issued with a black label rather than the current white label. The methods used in these modality studies required that at least two National Institute for Occupational Safety and Health (NIOSH)-certified B Readers1 interpret each participant’s DR chest radiograph presented as a soft copy image side-by-side with the digitized ILO standard radiographs, using two identical medical-grade monitors. In brief, these studies concluded that, with appropriate attention to image acquisition and soft copy display, both of the widely available digital radiography systems2 can be equivalent to FSR in the visualization and Classification of small interstitial lung opacities. Despite the subjective similarity between the “research” digitized standards and the new ILO Standard Digital Images (2011-D), to our knowledge, there is no objective evidence that Classifications acquired using either set would be equivalent. The objective of this study was to evaluate the equivalence of the “research” digitized standards and the ILO Standard Digital Images (2011-D) using paired digital and film chest radiographic examinations performed on the same day in miners from our previous studies. We searched for systematic differences in both the level of abnormality reported and the intra- and inter-reader variability.
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intramodality and intermodality comparisons of storage phosphor computed radiography and conventional film screen radiography in the recognition of small pneumoconiotic opacities
Chest, 2011Co-Authors: Scott A Laney, Edward L Petsonk, Michael D AttfieldAbstract:Background Digital radiography systems are replacing traditional film for chest radiographic monitoring in the recognition of pneumoconiosis. Methods To further investigate previous findings regarding the equivalence of film-screen radiographs (FSRs) and storage phosphor computed radiographs (CRs), FSRs and CRs from 172 underground coal miners were classified independently by seven National Institute for Occupational Safety and Health-approved B readers, using the International Labor Office (ILO) Classification of radiographs of pneumoconiosis. Results More CRs were classified as “good” quality compared with FSRs (prevalence ratio [PR], 1.5; 95% CI, 1.4-1.6; P , .001). B readers showed good overall agreement on scoring small opacity profusion using CRs vs FSRs (weighted κ, 0.58; 95% CI, 0.54-0.62). Significantly more irregular opacities (compared with rounded) were classified using CR images compared with FSR (PR, 1.3; 95% CI, 1.1-1.6; P = .01). Similarly, the smallest sized opacities (width P Conclusions Under optimal conditions, using standardized methods and equipment, reader visualization of small pneumoconiotic opacities does not appear to differ meaningfully, whether using CR or FSR. Variability in ILO Classifications between imaging modalities appears to be considerably lower than variability among readers. The well-documented challenge of reader variability does not appear to be resolved through the use of digital imaging alone, and additional approaches must be evaluated.
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comparison of storage phosphor computed radiography with conventional film screen radiography in the recognition of pneumoconiosis
European Respiratory Journal, 2010Co-Authors: A S Laney, Edward L Petsonk, Anita L Wolfe, Michael D AttfieldAbstract:Traditional film-screen radiography (FSR) has been useful in the recognition and evaluation of interstitial lung diseases, but is becoming increasingly obsolete. To evaluate the applicability of storage phosphor digital computed radiography (CR) images in the recognition of small lung opacities, we compared image quality and the profusion of small opacities between FSR and CR radiographs. We screened 1,388 working coal miners during the course of the study with FSR and CR images obtained on the same day from all participants. Each traditional chest film was independently interpreted by two of eight experienced readers using the International Labour Office (ILO) Classification of radiographs of pneumoconiosis, as were CR images displayed on medical-grade computer monitors. The prevalence of small opacities (ILO category 1/0 or greater) did not differ between the two imaging modalities (5.2% for FSR and 4.8% for soft copy CR; p>0.50). Inter-reader agreement was also similar between FSR and CR. Significant differences between image modalities were observed in the shape of small opacities, and in the proportion of miners demonstrating high opacity profusion (category 2/1 and above). Our results indicate that, with appropriate attention to image acquisition and soft copy display, CR digital radiography can be equivalent to FSR in the identification of small interstitial lung opacities.
