Akira M, Higashihara T, Yokoyama K, Yamamoto S, Kita N, Morimoto S, Ikezoe J, Kozuka T
Department of Radiology, National Kinki Chuo Hospital for Chest Disease, Osaka, Japan.
Radiology. 1989 Apr;171(1):117-23. doi: 10.1148/radiology.171.1.2928514.
High-resolution computed tomography (CT) was performed in 90 patients with pneumoconiosis who had small rounded opacities on radiographs. The CT appearances of radiographic type p small rounded opacities in 55 patients were compared with the appearances of type q and r opacities. Radiographic type p pneumoconiosis on high-resolution CT scans was characterized by tiny binary branching structures or a gathering of a few dots. In 21 of the 55 patients, nonperipheral, small areas of low attenuation with a central dot were found. On the basis of CT-pathologic correlation in two postmortem specimens, these tiny opacities and areas of low attenuation corresponded to irregular fibrosis around and along the respiratory bronchioles and to focal-dust emphysema, respectively. Focal emphysema was most commonly found in pneumoconiosis with p-type changes and can be identified with high-resolution CT scanning. The addition of high-resolution CT to chest radiography is useful in achieving more accurate categorization of the lesions.
