HRCT technique for ILD diagnosis has been extensively discussed [62] [63] [64] . To optimise spatial resolution, there is a general agreement to use thin sections, the smallest field of view and a sharp resolution algorithm. The most common HRCT feature of ILD is widespread ground-glass attenuation. Intralobular lines, irregular interlobular septal thickening and honeycombing are less common findings. Large subpleural air cysts in the upper lobes adjacent to areas of ground-glass opacities have been also reported in young children with ILD. These cysts are interpreted as paraseptal or irregular emphysema. HRCT is useful for ILD diagnosis and selection of lung area to be biopsied. It is proposed that it also may contribute to monitor disease activity and/or severity. However, evaluation is still needed to support a role of HRCT as a follow up tool in pediatric patients.