Nodular opacity

Complicated silicosis, also called PMF, occurs when the nodules coalesce and form large conglomerate lesions. Complicated silicosis is characterized radiographically by the presence of nodular opacities greater than 10 mm in diameter on the chest x-ray. CompHcated silicosis typically causes respiratory impairment. Recurrent bacterial infection may occur, and tuberculosis is a concern (NIOSH 1995). 

Fig. 3.3.4. a The chest X-ray in worker 2 showing nodular opacities in the middle and lower zones, b A thin-section computed tomography cut above the diaphragm showing widespread nodules and a mosaic effect... 

Fig.5.6a,b. A 69-year-old retired construction site worker, a Posterior-anterior chest radiograph shows irregular nodular opacities in both upper- and mid-zones, b Spiral computed tomography (7-mm thickness) through the lung apices show early conglomeration of nodules, particularly on the left... 

Two major forms of pulmonary emphysema can be detected using CT in patients with CWP bullous changes around PMF, considered as paracicatricial emphysema (Fig. 6.6), and irregular emphysematous lesions characterized by areas of low attenuation without definable walls that, when nodular opacities are present, are considered to be features of CWP (Remy-Jardin et al. 1992). 

Fig. 12.8a,b. Talc pneumoconiosis, (a) Chest radiograph shows fine nodular and tiny irregular opacities, diffusely distributed throughout both lungs. Confluent opacities are also seen, (b) Thin-section computed tomography scan shows fine nodular opacities, mainly distributed in the centrilobular location... 

On chest radiographs and CT, IPA appears as one or more nodular opacities. On CT, the CT halo sign may be seen a zone of ground glass opacity surrounding the nodule (Fig. 2.2.6). The nodular... 

Fig. 6.2.3. Halo sign due to angioinvasive aspergillosis in a 47-year-old woman after allogeneic hematopoietic stem cell transplantation. Close-up view of a HRCT scan at the right lower lohe shows a peripheral nodular opacity with a surrounding halo of ground-glass attenuation. These findings correspond to a nodular area of infarction surrounded by hemorrhage...

Centrilobular nodular opacities similar to those seen in Aspergillus bronchiolitis have been described in a number of conditions, including endobronchial spread of pulmonary tuberculosis, M. avium-intracellulare, viral and mycoplasma pneumonia (Aquino et al. 1996). The radiologic manifestations of Aspergillus bronchopneumonia are indistinguishable from those of bronchopneumonias caused by other microorganisms (Aquino et al. 1996 Franquet et al. 2004). 

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