The most common roles of longitudinal high-resolution computed tomography (HRCT) data in the evaluation of patients with diffuse lung disease (DLD)
| HRCT role | Notes |
| Initial diagnosis | Pattern may become more diagnostic over time Resolved or improved findings suggest an inflammatory or infiltrative component (e.g. not IPF) |
| Prognosis | Worsening abnormalities or rapid progression suggest a worse prognosis |
| Routine follow-up | Particularly helpful when PFTs may be inaccurate: patient unable to cooperate with PFTs; multifactorial restrictive disease (e.g. both fibrosis and pleural disease); mixed interstitial and airways disease; or early disease (below threshold of PFTs) Distinguish inflammation/infiltration from fibrosis on baseline HRCT |
| Detection of disease progression | Particularly helpful in patients with worsening symptoms and/or PFTs HRCT may be used as endpoint in clinical drug trials Quantitative analysis may provide a more objective analysis of findings and extent of lung involved |
| Evaluation of patients with acute lung symptoms | Distinguish progression of DLD versus a superimposed process (e.g. infection) Detection of acute exacerbation |
| Detection of complications | Detection of lung cancer, pulmonary hypertension and other abnormalities associated with DLD |
IPF: idiopathic pulmonary fibrosis; PFT: pulmonary function test.