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 interstitialabnormalities that can be progressive and turn into overt interstitial lung disease (ILD).In recent years, ILA have increasingly come into focus because several large cohortstudies have shown poorer clinical outcomes and increased mortality for patients withILA compared to those without ILA. The radiological classification into nonsubpleural,subpleural nonfibrotic and subpleural fibrotic as well as the assessment over timecan-together with clinical risk factors-help estimate clinical outcome. Clinicalmanagement of patients with ILA includes exclusion of ILD and risk-adapted controlintervals, especially in the presence of risk factors.