Pleural plaques are localized scars in the lungs. These localized scars have collagen fiber deposits and normally form after there has been exposure to asbestos fibers. Pleural plaques that form because of asbestos fibers are normally found in the parietal pleura, the lining of the inner wall of the chest. However, there are a few rare cases in which pleural plaques are found near a person’s rib cage. The plaques are considered a highly specific sign of asbestos exposure
Pleural plaques are unlike other diseases that form after being exposed to asbestos fibers in that the plaques do not cause any noticeable symptoms. They can only be found and detected on a CT scan or a radiograph. When found on a radiograph pleural plaques simply look like pleural thickening, an increase in the density of large areas of the pleura. When found on a CT scan pleural plaques look like localized areas of pleural thickening.
Pleural plaques are considered benign in that they are not cancerous. In addition, they cannot become malignant. Unfortunately, individuals who have pleural plaques often develop an asbestos related disease. These asbestos related diseases can include mesothelioma, asbestosis, and pleural effusion. It does not take much exposure to asbestos fibers in order to develop pleural plaques.
Asbestos and Pleural Plaques
One Belgian study looked at the differences of CT scans for patients with asbestosis, pleural plaques, and pleural thickening, all symptoms of asbestos exposure. Of 231 workers, 99 showed pleural or lung abnormalities. Of those whose scans showed pleural plaques, 64% had plaques on both lungs and 36% had plaques on only one. The presence of plaques alone, without any other sign, was not correlated with asbestosis or diffuse pleural thickening.
Though there is no known treatment that can reverse the effects of asbestos exposure, the appearance of pleural plaques can serve as a warning sign to evaluate any further symptoms carefully for the possibility of a deadly condition like asbestosis or mesothelioma. Patients found to have pleural plaques or other lung abnormalities will almost certainly be advised to stop smoking, as smoking raises the risk for a variety of respiratory problems.