title: Radiographic type p pneumoconiosis: high-resolution CT.
abstract: 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.
authors.affiliation: Department of Radiology, National Kinki Chuo Hospital for Chest Disease, Osaka, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Akira
authors.forename: T
authors.initials: T
authors.lastname: Higashihara
authors.forename: K
authors.initials: K
authors.lastname: Yokoyama
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.forename: N
authors.initials: N
authors.lastname: Kita
authors.forename: S
authors.initials: S
authors.lastname: Morimoto
authors.forename: J
authors.initials: J
authors.lastname: Ikezoe
authors.forename: T
authors.initials: T
authors.lastname: Kozuka
mesh_terms: D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011009:Pneumoconiosis / Q000000981:diagnostic imaging* / Q000473:pathology; D011656:Pulmonary Emphysema / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods*