The ILO digital radiographs (2011) -old wine in a new bottle?
V Murlidhar, Occupational Health and Safety Centre, OHSC Mumbai
5 November 2014
The two corner stones in the diagnosis of pneumoconiosis are occupational history and chest radiographs [1, 2]. In 1980 the international labour organisation (ILO) had published a set of 22 chest radiographs, based on patient x-rays taken over a 30 year period from 1950, that could be used for classification and grading of pneumoconiosis [3]. This has been an invaluable tool for epidemiological studies of pneumoconiosis [2, 4]. Nevertheless the set of radiographs is limited by the inability to cover all the grades of the disease. For example, there are only three films showing the “s” shape category: s/t 1/1, s/s 2/2 and s/s 3/3, whereas there are three more categories that can be encountered in clinical practice: s/s 0/1, s/s 2/1 and s/s 3/2 [5]. In 2011, the ILO published a set of digital radiographs for the classification of pneumoconiosis [6]. This was created by scanning the same set of 22 analog radiographs of the 1980 version. However it is of concern that some studies have shown that that profusion levels 0/1 and 1/1 may be under-estimated when using digital radiographs created for research purposes as compared to the analog set for comparision [4]. Other studies have validated that ILO digital radiographs can be a close approximation for the analog set of x-rays in classification of pneumoconiosis [4, 7-9]. Nevertheless, the digital ILO x-ray set is a mere copy of the analog set and have not been taken from real patients as was done during the creation of the analog set of 1980 [4, 6, 7]. Moreover, it did not the critical address the earlier shortcoming of the coverage of intermediate grades of perfusion. The occupational health and safety centre in Mumbai, have been examining cases of pneumoconiosis for the past 10 years [2, 10]. In our experience, the ILO digital radiographs do not add any new value to the ILO analog set of 1980 and may cause an under-reporting of x-rays that have 0/1 and 1/1 profusion. In this scenario, the authors’ attempt to create an aid to reading of digital radiography by computer modelling is a welcome addition to the available radiography methods for the diagnosis of pneumoconiosis [11].
References
1. American Thoracic Society: Diagnosis and initial management of nonmalignant diseases related to asbestos. Am J Respir Crit Care Med 2004, 170(6):691-715.
2. Murlidhar V, Kanhere V: Asbestosis in an asbestos composite mill at Mumbai: a prevalence study. Environ Health 2005, 4:24.
3. International Labor Organization (ILO): Guidelines for the Use of the ILO International Classification of Radiographs of Pneumoconiosis. Occupational Safety and Health Series, No. 22 (Rev.). Geneva, Switzerland: International Labor Office; 1980.
4. Halldin CN, Petsonk EL, Laney AS: Validation of the international labour office digitized standard images for recognition and classification of radiographs of pneumoconiosis. Acad Radiol 2014, 21(3):305-311.
6. International Labor Organization (ILO): Guidelines for the use of the ILO International Classification of Radiographs of Pneumoconioses, Revised edition 2011. Geneva, Switzerland: International Labor Office; 2011.
7. Franzblau A, Kazerooni EA, Sen A, Goodsitt MM, Lee SY, Rosenman KD, Lockey JE, Meyer CA, Gillespie BW, Petsonk EL, Wang ML: Comparison of digital radiographs with film radiographs for the classification of pneumoconiosis. Acad Radiol 2009, 16(6):669-677.
8. Larson TC, Holiday DB, Antao VC, Thomas J, Pinheiro G, Kapil V, Franzblau A: Comparison of digital with film radiographs for the classification of pneumoconiotic pleural abnormalities. Acad Radiol 2012, 19(2):131-140.
9. Lee WJ, Choi BS: Reliability and validity of soft copy images based on flat-panel detector in pneumoconiosis classification: comparison with the analog radiographs. Acad Radiol 2013, 20(6):746-751.
10. Jadhav AV, Roy N: Asbestosis: Past voices from the Mumbai factory floor. Indian J Occup Environ Med 2012, 16(3):131-136.
11. Zhu B, Luo W, Li B, Chen B, Yang Q, Xu Y, Wu X, Chen H, Zhang K: The development and evaluation of a computerized diagnosis scheme for pneumoconiosis on digital chest radiographs. BioMedical Engineering OnLine 2014, 13(1):141.
The ILO digital radiographs (2011) -old wine in a new bottle?
5 November 2014
The two corner stones in the diagnosis of pneumoconiosis are occupational history and chest radiographs [1, 2]. In 1980 the international labour organisation (ILO) had published a set of 22 chest radiographs, based on patient x-rays taken over a 30 year period from 1950, that could be used for classification and grading of pneumoconiosis [3]. This has been an invaluable tool for epidemiological studies of pneumoconiosis [2, 4]. Nevertheless the set of radiographs is limited by the inability to cover all the grades of the disease. For example, there are only three films showing the “s” shape category: s/t 1/1, s/s 2/2 and s/s 3/3, whereas there are three more categories that can be encountered in clinical practice: s/s 0/1, s/s 2/1 and s/s 3/2 [5]. In 2011, the ILO published a set of digital radiographs for the classification of pneumoconiosis [6]. This was created by scanning the same set of 22 analog radiographs of the 1980 version. However it is of concern that some studies have shown that that profusion levels 0/1 and 1/1 may be under-estimated when using digital radiographs created for research purposes as compared to the analog set for comparision [4]. Other studies have validated that ILO digital radiographs can be a close approximation for the analog set of x-rays in classification of pneumoconiosis [4, 7-9]. Nevertheless, the digital ILO x-ray set is a mere copy of the analog set and have not been taken from real patients as was done during the creation of the analog set of 1980 [4, 6, 7]. Moreover, it did not the critical address the earlier shortcoming of the coverage of intermediate grades of perfusion. The occupational health and safety centre in Mumbai, have been examining cases of pneumoconiosis for the past 10 years [2, 10]. In our experience, the ILO digital radiographs do not add any new value to the ILO analog set of 1980 and may cause an under-reporting of x-rays that have 0/1 and 1/1 profusion. In this scenario, the authors’ attempt to create an aid to reading of digital radiography by computer modelling is a welcome addition to the available radiography methods for the diagnosis of pneumoconiosis [11].
References
1. American Thoracic Society: Diagnosis and initial management of nonmalignant diseases related to asbestos. Am J Respir Crit Care Med 2004, 170(6):691-715.
2. Murlidhar V, Kanhere V: Asbestosis in an asbestos composite mill at Mumbai: a prevalence study. Environ Health 2005, 4:24.
3. International Labor Organization (ILO): Guidelines for the Use of the ILO International Classification of Radiographs of Pneumoconiosis. Occupational Safety and Health Series, No. 22 (Rev.). Geneva, Switzerland: International Labor Office; 1980.
4. Halldin CN, Petsonk EL, Laney AS: Validation of the international labour office digitized standard images for recognition and classification of radiographs of pneumoconiosis. Acad Radiol 2014, 21(3):305-311.
5. Occupational Safety and Health Series No. 22 (Rev. 2011): Guidelines for the use of the ILO International Classification of Radiographs of Pneumoconioses, Revised edition 2011 [http://www.ilo.org/wcmsp5/groups/public/---ed_protect/---protrav/---safework/documents/publication/wcms_168260.pdf]
6. International Labor Organization (ILO): Guidelines for the use of the ILO International Classification of Radiographs of Pneumoconioses, Revised edition 2011. Geneva, Switzerland: International Labor Office; 2011.
7. Franzblau A, Kazerooni EA, Sen A, Goodsitt MM, Lee SY, Rosenman KD, Lockey JE, Meyer CA, Gillespie BW, Petsonk EL, Wang ML: Comparison of digital radiographs with film radiographs for the classification of pneumoconiosis. Acad Radiol 2009, 16(6):669-677.
8. Larson TC, Holiday DB, Antao VC, Thomas J, Pinheiro G, Kapil V, Franzblau A: Comparison of digital with film radiographs for the classification of pneumoconiotic pleural abnormalities. Acad Radiol 2012, 19(2):131-140.
9. Lee WJ, Choi BS: Reliability and validity of soft copy images based on flat-panel detector in pneumoconiosis classification: comparison with the analog radiographs. Acad Radiol 2013, 20(6):746-751.
10. Jadhav AV, Roy N: Asbestosis: Past voices from the Mumbai factory floor. Indian J Occup Environ Med 2012, 16(3):131-136.
11. Zhu B, Luo W, Li B, Chen B, Yang Q, Xu Y, Wu X, Chen H, Zhang K: The development and evaluation of a computerized diagnosis scheme for pneumoconiosis on digital chest radiographs. BioMedical Engineering OnLine 2014, 13(1):141.
Competing interests
none