Visceral Pleural Thickening in Asbestos Exposure: The Occurrence and Implications of Thickened Interlobar Fissures.
Rockoff-SD; Schwartz-A; Hix-W; Rohatgi-P; Kagan-E; Kriebel-D
NIOSH 1990 Nov:1200-1201
The relationship between visceral pleural thickening and asbestos (1332214) exposure was examined. The cohort consisted of 220 asbestos exposed workers who were participating in an occupational health screening program. The comparisons consisted of 100 adult male patients who were being treated for nonthoracic problems. They had no known asbestos exposure and had chest X-rays which were read as having no active disease. Posterior/anterior chest X-rays were made and read for fissural thickening, parietal pleural plaques, and interstitial fibrosis. Among the comparisons, 84% had normal fissures and 16% had fissural thickening. The degree of thickening was rated as slight or moderate. Approximately 54.5% of the cohort had fissural thickening. After adjusting for age the extent of fissural thickening increased with increasing length of time since first asbestos exposure. The 50% probability of having fissural thickening occurred 21 years after first exposure. Approximately 38.2% of the asbestos workers had parietal pleural plaques. The 50% probability of having pleural plaques occurred 31 years after first exposure. Fissural thickening and pleural plaque formation occurred together in 85% of the subjects. Radiographic evidence of pulmonary fibrosis was usually not observed when fissural thickening was absent. Additionally, chest X-ray films from an unspecified number of patients with clinically or histologically confirmed asbestosis were also analyzed. Fissural thickening was noted in all asbestosis patients even when diffuse chest wall pleural thickening was absent. Histologically detected asbestosis occurred in the absence of radiographic changes in the lungs. The authors conclude that fissural thickening despite its not being specific for asbestos exposure can serve as an early indicator of asbestos related diseases of the thorax.
Chest-X-rays; X-ray-analysis; Lung-lesions; Asbestos-dust; Occupational-exposure; Respiratory-system-disorders; Histomorphology;
Asthma and Chronic Obstructive Pulmonary Disease; Disease and Injury; Respiratory-system-disorders;
Proceedings of the VIIth International Pneumoconioses Conference