Findings on CT that strongly suggest fibrotic interstitial lung disease
| Usual interstitial pneumonia (including idiopathic pulmonary fibrosis) |
| Basal predominance of honeycombing |
| Absence of relative subpleural sparing |
| Absence of centrilobular nodules |
| Nonspecific interstitial pneumonia |
| Relative subpleural sparing |
| Absence of lobular areas with decreased attenuation |
| Lack of honeycombing |
Information from Silva CI, Müller NL, Lynch DA, et al. Chronic hypersensitivity pneumonitis: differentiation from idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia by using thin-section CT. Radiology 2008; 246:288–297.