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Study Syllabus for Classification of Radiographs of Pneumoconioses

Radiograph Classification

Subset 2

Radiograph #24

Answer Key #24 (Updated 9/28/2023)

On initial inspection, this individual appears to have characteristic findings of silicosis and its sequelae. CWP may have the same appearance, however, and it is usually not possible to differentiate the two conditions. Large opacities are obvious in both lungs, more marked on the right. To differentiate pneumoconiosis for other diseases such as sarcoidosis or tuberculosis, one must search for associated findings that are almost always present in advanced pneumoconiosis. The most important include small rounded or irregular opacities, distortion of the intrathoracic organs because of retraction toward the conglomerate masses, compensatory emphysema, eggshell calcification in hilar or mediastinal lymph nodes. In this case, a pattern of small opacities is seen throughout both lungs, so the findings are consistent with pneumoconiosis. The case should be classified as follows:

The technical quality is good and is therefore classified 1.

Since there are parenchymal abnormalities consistent with pneumoconiosis, 2A is marked “YES.”

Small rounded opacities are present. Those whose shape and size correspond to the definition of q opacities (more than 1.5 mm but less than 3 mm in diameter) predominate so q is marked as the primary opacity type, however there are a number of opacities with diameters greater 3 mm so r is checked as the secondary type of small opacities. It is useful to compare the appearance of the small rounded opacities with the ILO Standards to confirm this classification with respect to size and shape.

All 6 lung zones are involved.

Comparison of the radiograph with the ILO Standards shows that the profusion of small opacities corresponds so well with the q/q – 1/1 Standard that no other Standard need be considered. The profusion is therefore 1/1 (the profusion was probably greater prior to the development of the large opacities and the compensatory emphysema). It is believed that multiple small opacities become incorporated into the mass, thus decreasing the apparent level of profusion.

The large opacities have a combined area less than the area of the right upper lung zone with the sum of the diameters of the large opacities exceeding 5 cm and they are, therefore, classified B. There is a poorly defined, possible additional large opacity seen through the heart in the left lower zone.

There are no pleural abnormalities consistent with pneumoconiosis.

As small pneumoconiotic opacities become incorporated into large opacities, the apparent profusion of small opacities may decrease. Note their relatively low profusion 1/1 in this patient with large pneumoconiotic opacities.

Other abnormalities include, cn, di and bu. A relatively large nodule seen through the heart in the left lower zone suggests an additional large opacity.