title: Spectrum of high resolution computed tomography findings in occupational lung disease: experience in a tertiary care institute.
abstract: OBJECTIVE
  To study the spectrum of high resolution computed tomography (HRCT) findings in occupational lung disease in industrial workers and to assess the utility of International classification of HRCT for occupational and environmental respiratory diseases (ICHOERD).
  
  
  METHODS
  Retrospective analysis of radiological data (radiographs and computed tomography chest scans) gathered over a period of 3 years (January 2010- December 2012) of industrial workers in an organised sector who presented with respiratory complaints. The HRCT findings were evaluated using ICHOERD.
  
  
  RESULTS
  There were 5 females and 114 males in the study, with a mean age of 49 years. These workers were exposed to different harmful agents including silica, asbestos, cotton dust, metal dust, iron oxide, organic dust, rubber fumes, plastic fumes, acid fumes, and oil fumes. There were 10 smokers in the study. The radiograph of chest was normal in 53 patients. 46% of these normal patients (21.8% of total) demonstrated positive findings on HRCT. When the radiograph was abnormal, HRCT provided more accurate information and excluded the other diagnosis. The HRCT findings were appropriately described using the ICHOERD. Bronchiectasis was the most common finding (44.5%) with mild central cylindrical bronchiectasis as the most common pattern. Pleural thickening was seen in 41 patients (34.5%). Enlarged hilar or mediastinal lymphnodes were seen in 10 patients (8.4%) with egg-shell calcification in 1 patient exposed to silica. Bronchogenic carcinoma was seen in 1 patient exposed to asbestos.
  
  
  CONCLUSIONS
  Occupational lung disease is a common work related condition in industrial workers even in the organized sector. Though chest radiograph is the primary diagnostic tool, HRCT is the undisputed Gold Standard for evaluation of these patients. Despite the disadvantage of radiation exposure, low dose CT may serve as an important tool for screening and surveillance. The ICHOERD is a powerful and reliable tool not only for diagnosis, but also for quantitative and analytical measurement of disease, thereby contributing to assessing the medical epidemiology of lung disease. It should always be used while evaluating HRCT of a patient with occupational lung disease.
authors.affiliation: Department of Radiodiagnosis, Delhi State Cancer Institute, Employee's State Insurance Hospital and Post Graduate Institute of Medical Science and Research, Basaidarapur, New Delhi, India.
authors.forename: Satija
authors.initials: S
authors.lastname: Bhawna
authors.affiliation: Institute of Occupational Health, Education and Research, Employee's State Insurance Hospital and Post Graduate Institute of Medical Science and Research, Basaidarapur, New Delhi, India.
authors.forename: U C
authors.initials: UC
authors.lastname: Ojha
authors.affiliation: Department of Radiodiagnosis, Employee's State Insurance Hospital and Post Graduate Institute of Medical Science and Research, Basaidarapur, New Delhi, India.
authors.forename: Sanyal
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Department of Pulmonary Medicine, Employee's State Insurance Hospital and Post Graduate Institute of Medical Science and Research, Basaidarapur, New Delhi, India.
authors.forename: Rajiv
authors.initials: R
authors.lastname: Gupta
authors.affiliation: Department of Pulmonary Medicine, Employee's State Insurance Hospital and Post Graduate Institute of Medical Science and Research, Basaidarapur, New Delhi, India.
authors.forename: Dipti
authors.initials: D
authors.lastname: Gothi
authors.affiliation: Department of Pulmonary Medicine, Employee's State Insurance Hospital and Post Graduate Institute of Medical Science and Research, Basaidarapur, New Delhi, India.
authors.forename: R S
authors.initials: RS
authors.lastname: Pal
keywords: Classification; ICHOERD; high resolution computed tomography; industrial worker; occupational lung disease