FIGURE 2.

Evolutionary radiological phases of pulmonary alveolar microlithiasis. a) Chest radiograph of the first, “precalcific” phase: diffuse noncalcific micronodules. b) Chest radiograph of the second phase: diffuse, scattered, calcific micronodules with a greater concentration in the medial and inferior regions, the outlines of the heart and diaphragm are still clearly visible. c) Chest radiograph of the second phase (variant): micronodules show a larger diameter (∼2–4 mm), uniformly distributed. d) High-resolution computed tomography scan of fig. 2c: diffuse endoalveolar micronodules with thickening of the interstitial picture.