A focal pleural thickening is called a pleural plaque. It may be calcified.
A focal pleural thickening is called a pleural plaque. It may be calcified. Pleural plaque is usually the sequela of previous diseases of the pleura, like pleural effusion, hemothorax, or empyema thoracis.
Q. How do you differentiate a lung lesion from a pleural plaque?
Pleural plaque is usually peripheral in location. When it is in the periphery of the lungs, then it appears dense because of overlap. It appears linear and not rounded. A lung nodule appears rounded.
Sometimes a pleural plaque will be posterior or anterior in a PA chest X-ray, when they lie in the posterior or anterior pleural space. In such a case, you can recognize it by its-
- Geographical shape.
- Denser towards the periphery and less dense towards the center.
In this image, we can see many calcified pleural plaques. Note that they have a geographical shape ( shaped like country borders) instead of a rounded shape, and they are most denser in the periphery than the centre ( blue arrow). Basal pleural plaques can also be appreciated in the bilateral diaphragmatic pleura.
Case courtesy of Dr Jeremy Jones, Radiopaedia.org, rID: 12388