Study Syllabus for Classification of Radiographs of Pneumoconioses
Section 3: Pleural Abnormalities (Continued)
Radiograph #18A and Radiograph #18B
Pleural thickening, whether circumscribed or diffuse, may be seen only in profile, only face on, or in combination. Each form of pleural thickening that is seen should be separately recorded, even though it may appear that these different forms, in fact, represent a single extended zone of pleural thickening seen in a variety of projections.
Remember the rule distinguishing localized plaque from diffuse pleural thickening: plaque spares the apex and costophrenic angle (Radiograph #17A); diffuse pleural thickening involves the costophrenic angle (Radiograph #18A). Lastly, it should be emphasized that it is common to see unequivocal plaque formation in the absence of small parenchymal pneumoconiotic opacities (Radiograph #17A).
Pleural calcification may be seen with exposure to asbestos, but may also be secondary to trauma or old infection. The calcification associated with pneumoconiosis is more often bilateral than unilateral. Unilateral pleural calcifications should be classified as pneumoconiosis (Radiograph #16), however one may note other etiologies in the comments section if they are suspected. One should search for other findings indicative of pneumoconiosis before attributing unilateral pleural calcification to a pneumoconiotic process. If pleural calcification is linear, it is relatively easy to recognize. It may be discontinuous and may appear in the form of punctate opacities or spicules, making recognition more difficult. In particular, punctate or spiculated calcification seen in face-on plaques may be confused with small pneumoconiotic opacities or calcified granulomas. Large plaques containing marginal calcification may appear to have rolled edges and have been likened in appearance to holly leaves or candle wax.
Hemidiaphragmatic calcification is seen in Radiograph #15B.
In Radiograph #19, extensive diffuse pleural thickening is present on the left. Note the obliteration of the left constophrenic angle and the veiling of the left lower lung zone.
Furthermore, in Radiograph #19, the face on pleural plaque demonstrates calcifications. On the right, the pleural process is diffuse with extent 3 and the width is c. Face on and in profile plaque with calcification is seen on the left. Note, do not confuse scapula overlay with pleural shadows.