Imaging of Occupational Lung Disease
The Royal Australian and New Zealand College of Radiologists®
Imaging of Occupational Lung Disease
Clinical Radiology
Position Statement
Name of document and version: Imaging of Occupational Lung Disease, Version 1
Approved by: Faculty of Clinical Radiology Council
Date of approval: 04 October 2019
ABN 37 000 029 863 Copyright for this publication rests with The Royal Australian and New Zealand College of Radiologists ®
The Royal Australian and New Zealand College of Radiologists Level 9, 51 Druitt Street Sydney NSW 2000 Australia
New Zealand Office: Floor 6, 142 Lambton Quay, Wellington 6011, New Zealand
Email: [email protected] Website: www.ranzcr.com Telephone: +61 2 9268 9777
Disclaimer: The information provided in this document is of a general nature only and is not intended as a substitute for medical or legal advice. It is designed to support, not replace, the relationship that exists between a patient and his/her doctor.
TABLE OF CONTENTS
1. Introduction 4 2. Role of Radiologists 4 3. Role of chest x-ray versus high resolution CT chest 4 4. Recommendations 5
5. Appendices 8 Imaging 6. References 12
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About the College
The Royal Australian and New Zealand College of Radiologists (RANZCR) is a not-for-profit association of members who deliver skills, knowledge, insight, time and commit to promoting the science and practice of the medical specialties of clinical radiology (diagnostic and interventional) and radiation oncology in Australia and New Zealand.
The Faculty of Clinical Radiology, RANZCR, is the peak bi-national body for setting, promoting and continuously improving the standards of training and practice in diagnostic and interventional radiology for the betterment of the people of Australia and New Zealand.
The work of the College is scrutinised and externally accredited against industry standard by the
Australian Medical Council and the Medical Council of New Zealand. October 2019 October Our Vision
RANZCR as the peak group driving best practice in clinical radiology and radiation oncology for the benefit of our patients.
Our Mission
To drive the appropriate, proper and safe use of radiological and radiation oncological medical services for optimum health outcomes by leading, training and sustaining our professionals.
Our Values
Commitment to Best Practice
Exemplified through an evidence-based culture, a focus on patient outcomes and equity of access to high quality care; an attitude of compassion and empathy.
Acting with Integrity
Exemplified through an ethical approach: doing what is right, not what is expedient; a forward thinking | © The Royal Australian and New Zealand College of Radiologists® | | Radiologists® of College Zealand New and Australian Royal The © | and collaborative attitude and patient-centric focus.
Accountability
Exemplified through strong leadership that is accountable to members; patient engagement at
isease, Version 1 Version isease, professional and organisational levels.
D ung ung
L Code of Ethics
The Code defines the values and principles that underpin the best practice of clinical radiology and radiation oncology and makes explicit the standards of ethical conduct the College expects of its
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Imaging Imaging
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1. INTRODUCTION
1.1 Purpose and scope
In Australia a significant incidence of silicosis in workers exposed to the dust from high silica content engineered stone has been identified. Imaging has a central role in the diagnosis and monitoring of occupational lung diseases including disease resulting from exposure to
engineered stone (1). A common context in which this exposure occurs is in working with Imaging kitchen benchtops.
The spectrum of diseases associated with respirable crystalline silica includes: of
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• Silicosis ccupational • Lung cancer • Chronic obstructive pulmonary disease (COPD)
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• Rheumatoid arthritis isease, Version1 • Chronic kidney disease In Australian workers the spectrum of lung disease being identified includes accelerated silicosis without calcified hilar or mediastinal lymphadenopathy, chronic silicosis complicated by
progressive massive fibrosis, and lymph node enlargement (2). |©The Royal Australian and New Zealand College of Radiologists® | Whilst there have been no reported cases in New Zealand, similar patterns of disease are anticipated due to similar products being used across both countries. Engineered stone workers may present for chest imaging as part of screening programs or
undergo imaging for unrelated reasons.
1.2 Definitions
College means The Royal Australian and New Zealand College of Radiologists.
Member means a member of the College.
2. ROLE OF RADIOLOGISTS
Radiologists are medical specialists who are experts in diagnostic imaging. The role of Radiologists in occupational lung disease is to use their expert knowledge to detect and characterise abnormalities and provide a definitive diagnosis or differential diagnosis to assist with informing disease management (3). Accurate diagnosis of occupational lung disease with low inter-reader variability is highly desirable for clinical, research and medicolegal reasons.
3. ROLE OF CHEST X-RAY VERSUS HIGH RESOLUTION CT CHEST October2019 3.1 Australian experience with imaging of engineered stone workers
Preliminary review of data from Australian centres caring for workers with engineered stone related lung disease has found that chest x-rays are failing to reliably detect disease (2,4). In one cohort of Queensland workers 43% with ILO classified normal chest x-rays had disease visible on CT. In the same cohort bilateral progressive massive fibrosis opacities was only visible on chest x-ray in 64% of workers with this finding on CT (4). A range of interstitial lung abnormalities have been identified on CT in engineered stone workers, including subtle findings such as small ground glass attenuation nodules. The relationship of some of the findings to morbidity and outcomes is uncertain.
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CT has replaced the chest x-ray in the diagnosis of non-occupational diffuse lung diseases and has been recommended for use in occupational lung diseases (5,6). While historically chest x- ray has been the primary imaging modality used to detect lung disease due to silica exposure, CT has a higher sensitivity for detecting early disease, and greater accuracy in characterising the patterns of disease (5,6). For these reasons, and in the context of the findings described in Australian workers, CT of the chest is strongly recommended as the primary imaging modality to be used for screening exposed workers.
3.2 Role of chest x-ray and CT classification systems
Classification systems exist for use with chest x-ray and CT in the context of occupational lung disease. Use of these classification systems does not replace the requirement for a diagnostic imaging report. These systems are intended to reduce inter-reader variability through
October 2019 October standardising the classification of abnormalities. They support comparisons of data and have utility in medicolegal settings such as compensation claims (7,8). Chest x-ray and referral without occupational history is likely to result in false negative interpretations of CXRs.
The International Labour Organisation (ILO) has guidelines for the classification of radiographs of pneumoconiosis that were developed to standardise classification of lung opacities and facilitate international comparisons of data (9). Although the ILO system is not used for patient care it has a role in screening and surveillance, and for medicolegal purposes. The National Institute for Occupational Safety and Health (NIOSH) in the USA oversees A and B reader programs to train and document proficiency of physicians who use the ILO classification for pneumoconiosis (10,11).
An equivalent classification system has been developed for CT. The International Classification of High-resolution Computed Tomography (HRCT) for Occupational and Environmental Respiratory Diseases (ICOERD) was developed for the screening, diagnosis, and epidemiological reporting of respiratory diseases caused by occupational exposures (8). The
target of this classification is asbestos-related pulmonary diseases, silicosis, and tobacco exposure-related respiratory diseases such as emphysema.
While the principles of the ILO system and ICOERD systems are relevant and applicable to occupational lung disease in Australia, a mandatory requirement for NIOSH reader
accreditation is not recommended for Radiologists reporting these studies in Australia. | © The Royal Australian and New Zealand College of Radiologists® | | Radiologists® of College Zealand New and Australian Royal The © |
4. RECOMMENDATIONS isease, Version 1 Version isease,
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ung ung L • RANZCR will ensure its membership is kept up to date on the emerging issue of occupational lung disease in engineered stone workers and any related
recommendations.
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Imaging Imaging diagnosis of abnormalities on chest x-ray or CT.
• In conjunction with other stakeholders, RANZCR supports raising general awareness amongst community and hospital health care providers of the importance of including information about occupational and non-occupational exposures associated with an increased risk for lung disease in the clinical details provided on referrals for imaging.
• With input from its special interest group, the Australian and New Zealand Society of Thoracic Radiology (ANZSTR) RANZCR will:
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o Advocate for Radiologist participation in taskforces, working groups and other initiatives relating to engineered stone (and other occupational lung disease), including those led by other professional bodies, government and non- government agencies.
o Support provision of educational opportunities to assist members in the development and maintenance of skills in diagnosing and characterising occupational lung disease.
4.2 Specific recommendations related to diagnosis, imaging and reporting of occupational lung disease due to engineered stone Imaging
4.2.1 Investigation pathways for workers at risk of occupational lung disease from of
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• The wellbeing of workers is paramount.
• Pathways for the diagnosis of occupational lung disease due to engineered stone L
should be evidence based and free of commercial bias. ung
o All individuals advising on or participating in pathway design should be asked to D disclose any conflicts of interest (disclosure should be documented). isease, Version1 • Pathways should be developed through a multidisciplinary consensus building process including Clinical Radiologists as the imaging experts. • Pathways should be deliverable in a variety of health care settings and as consistent as reasonably achievable across Australia and New Zealand. • The limited sensitivity of chest x-ray for the detection of disease needs to be |©The Royal Australian and New Zealand College of Radiologists® | acknowledged in the pathway development process. CT is strongly recommended for screening all workers. Participants in pathway design should actively consider how to lower/remove barriers to accessing CT.
• In addition to via screening, pathways should accommodate any at risk worker with
pulmonary or pleural abnormalities incidentally detected on chest x-ray or CT performed for non-occupational indications being able to access specialist review. • A multidisciplinary approach to establishing a diagnosis of interstitial lung disease (ILD) due to occupational exposure is strongly recommended. o Radiologists are integral members of the ILD multidisciplinary team. o In the New Zealand practice environment regional ILD services are recommended as the access point for multidisciplinary review.
4.2.2 Imaging technique recommendations
CT is strongly recommended for screening all workers at risk of occupational lung disease from engineered stone exposure. Any concerns about the relatively higher radiation dose received from CT must be balanced against the benefits of a more sensitive test that reliably detects
disease in exposed workers. Information on ionising radiation and health, can be found on the October2019 Australian Radiation Protection and Nuclear Safety Agency website: https://www.arpansa.gov.au/understanding-radiation/radiation-sources/more-radiation-
sources/ionising-radiation-and-health
A) CT Technique:
High-resolution (HR) images are required to detect and characterise occupational lung disease. A volumetric CT of the entire chest at end inspiration is recommended along with expiratory images. • On the inspiratory CT the entire lungs should be assessed without an interslice gap. Scan range for the inspiratory acquisition should extend from lung apices to the costophrenic sulci. Contiguous high-resolution (HR) images should be reconstructed at
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0.625-mm to 1.5-mm slice thickness with a high spatial frequency reconstruction algorithm (12). All contiguous high-resolution images must be archived to ensure they are available for any subsequent reviews and for comparison. • Expiratory imaging may be acquired as a volume or traditional gapped HRCT technique depending on which yields the lowest dose/is most appropriate for scanner technology. • Prone HRCT images should only be used in selected cases where they will add value i.e., they should not be routinely performed. • Utilisation of techniques to reduce dose to as low as reasonably achievable is
recommended. Care should be taken to ensure resulting image quality supports the detection of subtle abnormalities including small ground glass attenuation nodules. • Intravenous contrast should not be used when performing CT for suspected diffuse interstitial lung disease as intrapulmonary contrast can obscure subtle pulmonary
October 2019 October findings (12).
B) Chest x-ray technique:
Although chest x-ray lacks sensitivity and cannot characterise disease as accurately as CT, a baseline chest x-ray is recommended in combination with CT. In selected cases this could allow a chest x-ray to be used as an alternative to CT in ongoing follow-up. A quality PA chest x-ray optimised for assessing the lungs is recommended as a baseline test in conjunction with a CT chest (6,13,14).
C) Reporting recommendations
All examinations undertaken to screen for occupational lung disease due to engineered stone require a diagnostic imaging report by a Radiologist.
To assist with reducing inter-reader variability and help standardise report content, use of standard report templates for chest x-ray (appendix 1) and CT is strongly recommended (appendix 2).
To ensure there is clarity with respect to the final interpretation of a chest x-ray and CT, use of
| © The Royal Australian and New Zealand College of Radiologists® | | Radiologists® of College Zealand New and Australian Royal The © | standardised comments is strongly recommended, and where appropriate, use of standardised recommendations aligned with local pathways is strongly recommended (appendix 1 and 2).
Reporting of the imaging of occupational lung disease should be undertaken by Radiologists with experience in the interpretation of chest x-rays and CT for interstitial lung disease, familiar
isease, Version 1 Version isease, with the patterns seen in occupational lung disease, and the common differential diagnoses.
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ccupational ccupational While the ILO accreditation in chest x-ray reading is acknowledged in its historical
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standardised report, however, is recommended (see appendices 1 and 2). Imaging Imaging Radiologists reporting chest x-rays and HRCT for occupational lung disease should also be regularly reporting chest x-rays and HRCT for other ILDs.
Radiologists reporting HRCT for occupational ILD should ideally participate in interstitial lung disease multidisciplinary meetings at established ILD sites (or an equivalent review group).
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Radiologists reporting HRCT for occupational lung disease should be undertaking CPD activities specific to imaging of ILD including due to occupational exposures.
It is recommended that Radiologists reporting chest x-rays and HRCT for ILD in general and occupational lung disease incorporate peer review of performance and peer discussion of occupational lung disease cases in their CPD activities.
RANZCR will, with input from its thoracic imaging special interest group (The Australian and New Zealand Society of Thoracic Radiology ANZSTR), encourage and facilitate the sharing of Imaging experience and knowledge and the development of evidence-based guidelines to support its
members to provide quality care to workers with suspected occupational lung disease.
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5. APPENDICES L 1. Chest x-ray reports in suspected occupational lung disease should contain the ung
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Clinical information
Technique PA chest x-ray
Exam quality |©The Royal Australian and New Zealand College of Radiologists® | Specify if: Satisfactory positioning (costo-pleural junctions included) Satisfactory exposure (fine detail of parenchymal markings visible, vascular markings visible through heart) or underexposure (may over-call profusion) or overexposure (may under-call profusion)
Findings Fibrotic abnormalities Specify presence/absence of chest x-ray findings suggesting: o Reticular abnormality o Traction bronchiectasis o Honeycombing
Non-fibrotic Abnormalities Specify presence/absence of chest x-ray findings suggesting: • Diffuse pulmonary opacity • Consolidation or ground glass opacity • Nodules • Airway abnormalities • Bronchial wall thickening, bronchiectasis
• Emphysema, cysts October2019 Masses Specify presence/absence of chest x-ray findings suggesting: • PMF/conglomerate • Rounded atelectasis • Bronchogenic carcinoma
Other findings Specify presence/absence of chest x-ray findings suggesting: • Lymph node enlargement including whether hyperdense or calcified • Pleural abnormality • Pulmonary arterial enlargement
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• Oesophageal dilation, hiatal hernia
Impression Specify imaging classification based on chest x-ray: • No evidence of occupational exposure related disease. or • Abnormalities are present that may be due to occupational exposure related disease.
Dedicated non-contrast HRCT chest recommended. • Differential diagnosis with level of confidence • Change since prior imaging
October 2019 October Adapted from Chung C, Lynch D and Cox CW et al (5,15).
Sample x-ray report template:
CLINICAL DETAILS:
COMPARISON:
TECHNIQUE: PA Chest
FINDINGS: Lungs and airways: Abnormal findings:
Relevant negative findings: No nodules. No findings to suggest emphysema, airways disease or interstitial lung disease. No findings to suggest progressive massive fibrosis/conglomerate mass, rounded atelectasis or bronchogenic carcinoma.
| © The Royal Australian and New Zealand College of Radiologists® | | Radiologists® of College Zealand New and Australian Royal The © | Heart and mediastinum:
Relevant negative findings: Allowing for the limitations of chest x-ray: No enlarged thoracic lymph nodes. No calcified lymph nodes. Normal MPA. No hiatus hernia.
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IMPRESSION:
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Or of Abnormalities are present that may be due to occupational exposure related disease. Dedicated non-contrast HRCT chest recommended.
Imaging Imaging Differential diagnosis with level of confidence Change since prior imaging
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2. CT reports in suspected occupational lung disease should contain the following:
Clinical information
Technique End Inspiratory CT whole chest 1mm
Expiratory HRCT Imaging
Exam quality of
Fibrotic abnormalities O
• Specify presence/absence of and axial and craniocaudal distribution of: ccupational o Reticular abnormality o Traction bronchiectasis, bronchiolectasis
o Honeycombing L Non-fibrotic Abnormalities ung
Specify presence/absence of: D isease, Version1 • Diffuse pulmonary opacity o Consolidation o Ground glass opacity o Crazy paving
• Nodules |©The Royal Australian and New Zealand College of Radiologists® | o Specify if solid or ground glass attenuation, and distribution perilymphatic/subpleural or centrilobular or random • Airway abnormalities o Mosaic attenuation/air-trapping
o Bronchial wall thickening o Bronchiectasis o Emphysema o Cysts
Masses Specify presence/absence of: • PMF/conglomerate • Rounded atelectasis • Bronchogenic carcinoma
Other findings • Specify presence/absence of: o Lymph node enlargement including whether hyperdense or calcified o Pleural abnormality o Pulmonary arterial enlargement October2019 o Oesophageal dilation o Hiatal hernia
Impression • It is recommended that the final diagnosis of occupational exposure related disease is made by multidisciplinary consensus therefore a simple classification at the end of each report is recommended: • No evidence of occupational exposure related disease. or • Abnormalities are present that may be due to occupational exposure related disease. Multidisciplinary review is recommended.
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• Alternative imaging classification: • Consistent with, or probable, or indeterminate, for occupational exposure related disease or most consistent with a non-occupational disease diagnosis. • Differential diagnosis with level of confidence • Change since prior imaging
Adapted from Chung C, Lynch D and Cox CW et al (5,15).
Sample CT report template:
October 2019 October CLINICAL DETAILS:
COMPARISON:
TECHNIQUE: End Inspiratory 1mm CT Chest Expiratory HRCT
FINDINGS: Lungs and airways: Abnormal findings:
Relevant negative findings: No ground glass opacity, consolidation or crazy paving. No reticulation, traction bronchiectasis, bronchiolectasis or honeycombing. No nodules.
No progressive massive fibrosis/conglomerate mass, rounded atelectasis or bronchogenic carcinoma. No mosaic attenuation/air trapping, bronchial wall thickening, bronchiectasis, emphysema or cysts.
Pleura:
Lymph nodes: | © The Royal Australian and New Zealand College of Radiologists® | | Radiologists® of College Zealand New and Australian Royal The © |
Relevant negative findings: No enlarged thoracic lymph nodes. No hyperdense or calcified lymph nodes.
Other mediastinal: isease, Version 1 Version isease,
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Relevant negative findings: ung ung
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Upper abdomen: ccupational ccupational
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IMPRESSION: Imaging Imaging No evidence of occupational exposure related disease or Abnormalities are present that may be due to occupational exposure related disease. Multidisciplinary review is recommended. or Consistent with, or probable, or indeterminate, for occupational exposure related disease or most consistent with a non-occupational disease diagnosis.
Differential diagnosis with level of confidence.
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Change since prior imaging.
6. REFERENCES
1. WorkCover Queensland. Immediate action required to prevent exposure to silica for engineered stone benchtop workers. WorkCover Queensland; 2018. 2. Edwards G. Accelerated Silicosis Forum, Wellington, New Zealand June 2019. 3. Royal Australian and New Zealand College of Radiologists. The Role and value of the Clinical Radiologist Position Paper Sydney: RANZCR; 2014 November 2014. Imaging 4. Newbigin K et al. Stonemasons with silicosis: Preliminary findings and a warning message
from Australia. Respirology 2019 of
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5. Cox CW, Rose CS, Lynch DA. State of the Art: Imaging of Occupational Lung Disease. ccupational Radiology 2014 270(3): 681-696. 6. Bacchus L et al. American College of Radiology (ACR) Appropriateness Criteria: Occupational
Lung Diseases 2014. L 7. Halldin C et al. Pneumoconiosis Radiographs is a Large Population of US Coal Workers: ung
Variability in A Reader and B reader Classifications by Using the International Labour Office D isease, Version1 Classification. Radiology 2017 284(3): 870-876. 8. Tamura T et al. Relationships (I) of International Classification of High Resolution Computed Tomography for Occupational and Environmental Respiratory Diseases with the ILO International Classification of Radiographs of Pneumoconioses for parenchymal abnormalities.
Industrial Health 2015, 53, 260–270. |©The Royal Australian and New Zealand College of Radiologists® | 9. Guidelines for the use of the ILO International Classification of Radiographs of Pneumoconioses. Revised edition 2011, Geneva, International. 10. Centres for Disease Control and Prevention. The National Institute for Occupational Safety
and Health (NIOSH). Chest Radiography. Issues in classification of chest radiographs. CDC;
May 2011. https://www.cdc.gov/niosh/topics/chestradiography/interpretation.html 11. Centres for Disease Control and Prevention. The National Institute for Occupational Safety and Health (NIOSH). Chest Radiography. The NIOSH B Reader Program. CDC; March 2019. https://www.cdc.gov/niosh/topics/chestradiography/breader.html 12. ACR–SPR–STR Practice Parameter for the Performance of High-Resolution Computed Tomography (HRCT) of the Lungs in Adults 2015. 13. ACR–SPR-STR Practice Parameter for the Performance of Chest Radiography 2017. 14. Standards for acquiring digital chest radiography images for medical surveillance of Queensland coal mine workers. Department of Natural Resources and Mines. State of Queensland 2017. 15. Jonathan Chung, MD, David Lynch, MD Pulmonary Fibrosis Foundation, Care Centre Network Radiology working group guideline content for HRCT report in suspected pulmonary fibrosis. On line: https://www.pulmonaryfibrosis.org/medical-community/pff-patient-registry/statements- hrct
October2019
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