Study Syllabus for Classification of Radiographs of Pneumoconioses
Section 3: Pleural Abnormalities (Continued)
In Radiograph #16, the extent of the right-sided in-profile calcified plaque is less than one-fourth of the lateral chest wall, indicating extent 1.
In Radiograph #17A, the extent of in-profile plaque on the right is extent 3 – greater than one half, and on the left is extent 2 – greater than one-fourth but less than one-half of the lateral chest wall. Additional face-on plaques are visible as ill-defined hazy opacity overlying the anterior third through sixth ribs. The face-on opacity on the left is partially well-defined laterally and medially but ill-defined superiorly and inferiorly. The summed extent of the right-side plaques is greater than one-half the vertical length of the lateral chest wall, extent 3. The face-on plaques in the left hemithorax of Radiograph #17A are visible as partially well-defined hazy opacity overlying the second through sixth anterior ribs. A plaque overlying the anterior second rib is well-defined laterally but does not blend in with the lateral chest wall, so it does not constitute a profile plaque. The summed extent of these plaques is greater than one-half the lateral chest wall, extent 3. Calcification attenuation is visible in the face-on plaques on the left with some linear well-defined densities. A check is placed in the L box on the “Face-on” line under “Calcification” in Section 3B.
Width. The width of in-profile plaque is measured as the maximum distance from the inner rib margin along the lateral chest wall to the sharp inner margin of the plaque. Depending on the purpose of the radiograph, recording of width may not be required. Face-on plaques are not classified in terms of width.
The sharp inner margin of the plaque is not necessarily in the same coronal plane as the inner margin of the rib at the lateral chest wall. The 2011 Classification requires a minimum width of 3 mm for in-profile pleural plaque or thickening to be recorded as present. The width of in-profile plaque is designated as follows:
a = maximum width of at least 3 mm up to 5 mm
b = maximum width over 5 mm and up to 10 mm
c = maximum width over 10 mm
Therefore, the maximum width for the in-profile plaque on the left in Radiograph #16 is b.