[Pathologic-HRCT correlation of pneumoconiosis--a study on inflation-fixed lungs].
High resolution computed tomography (HRCT) findings were correlated with pathologic features of 14 inflation-fixed postmortem lungs with pneumoconiosis to evaluate the ability of HRCT to depict pneumoconiotic changes. The results are as follows: 1) Irregular peribronchiolar and interlobular fibrosis was the most constant pathologic feature in all lungs. This pathologic finding corresponded to an area of hazy increased density or reticular density on HRCT. The reticular density on HRCT became coarser with the progression of fibrosis. Mild fibrosis, confirmed by histologic procedures, could not be detected with HRCT. 2) Subpleural curvilinear line seen on HRCT in 5 lungs corresponded to band-like zone of fibrosis containing bronchioles or zone of collapsed alveoli with fibrotic thickening on histologic sections. A subpleural band-like zone of organized pneumonia was recognized in 2 cases. Subpleural patchy density was seen on HRCT in 8 cases. Five of them were histologically a focus of fibrosis and the other 3 were localized pulmonary edema, organized pneumonia, or atelectasis without fibrosis. 3) Pneumoconiotic nodules were located at centrilobular portion or along interlobular septa on histologic sections. These location were correspond to HRCT findings. They were round with irregular borders and were surrounded by a zone of enlarged air space. Overall 71% (182/256) of pathologically proved nodules were seen on HRCT, but 63% (52/83) of small "p" type nodules (smaller than 1.5 mm) could not be detected. Enlarged air space at the periphery of the nodules was seen on HRCT in 78% (122/156) of those pathologically proved. 4) A total of 12 lesions of progressive massive fibrosis was found in 5 lungs. An irregular border, seen on HRCT in all lesions, was pathologically based on the fibrosis extending into the surrounding alveoli and partially confluencing pneumoconiotic micronodules. Pleural indentation was seen in 8 lesions. Patent residual bronchi, spared from destructive fibrotic change, were seen as strand-like air density on HRCT in 4 of 6 lesions. 5) Focal emphysema was found pathologically in 9 of the 14 lungs. They appeared as non-peripheral, small low-attenuation area with a central dot on HRCT. The dot histologically corresponded to fibrosis around centriacinar bronchovascular bundle. The limit of visibility of this form of emphysema on HRCT was 2.0 mm in size. When emphysema was complicated by pneumonia, some showed honeycomb appearance on HRCT. 6) It is concluded that HRCT can detect and quantify the various pneumoconiotic changes of the lung and the HRCT-pathological correlation data presented here will be useful for the interpretation of the findings in clinical cases of pneumoconiosis.
Hirakata
K
K
Department of Radiology, University of Occupational and Environmental Health, School of Medicine.
D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D066298:In Vitro Techniques; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology*; D008875:Middle Aged; D011009:Pneumoconiosis / Q000000981:diagnostic imaging* / Q000473:pathology; D014057:Tomography, X-Ray Computed