Bleomycin-induced fibrosis in pigs: evaluation with CT.

Purpose: To establish an animal model for use in evaluation of early morphologic changes of pulmonary fibrosis by means of precise correlation of findings at thin-section computed tomography (CT) and pathologic findings.
Materials and Methods: Bleomycin (1.0-2.5 U per kilogram of body weight) was delivered selectively into the left lower lobe bronchus via balloon catheter in five Yorkshire pigs. Sequential CT examinations were performed at regular intervals. The animals were killed at follow-up of 5 days to 4 weeks. At autopsy, the lungs were removed, inflated, fixed and dried, and subsequently sliced into sections that corresponded to the CT sections. The fixed lungs were examined with thin-section CT, radiography, and histologic studies.
Results: There was good correlation between pathologic findings at CT and specimen radiography. Histologic study revealed signs of pneumonitis and developing fibrosis.
Conclusions: This disease model is suitable for radiologic and pathologic evaluation of interstitial fibrosis. CT was sensitive in detection of bleomycin-induced abnormalities.