[Interstitial lung abnormalities : What the radiologist needs to know]

Interstitial lung abnormalities (ILA) are incidental findings on computed tomography (CT), particularly in elderly patients and smokers. They describe mild interstitial abnormalities that can be progressive and turn into overt interstitial lung disease (ILD). In recent years, ILA have increasingly come into focus because several large cohort studies have shown poorer clinical outcomes and increased mortality for patients with ILA compared to those without ILA. The radiological classification into nonsubpleural, subpleural nonfibrotic and subpleural fibrotic as well as the assessment over time can-together with clinical risk factors-help estimate clinical outcome. Clinical management of patients with ILA includes exclusion of ILD and risk-adapted control intervals, especially in the presence of risk factors.