[Radiological diagnosis of interstitial lung disease]

Diffuse interstitial lung diseases (ILDs) represent a complex and heterogeneous group of pulmonary disorders, requiring a structured, rigorous, and integrated radiologic approach for accurate diagnosis. High-resolution computed tomography (CT) remains the cornerstone examination, enabling precise identification of elementary lesions and their organization into diagnostic imaging patterns that are critical for etiologic classification. This analysis, guided by the most recent international guidelines, relies on strict technical protocols (thin slices, expiratory and prone acquisitions), longitudinal comparative reading, and systematic multidisciplinary discussion. The recognition of progressive pulmonary fibrosis as a distinct clinical entity with significant prognostic and therapeutic implications underscores the need for consistent and reproducible imaging assessment. Emerging tools such as artificial intelligence and photon-counting CT are enhancing early lesion detection, quantitative analysis, and prognostic stratification, allowing for dynamic evaluation of ILD progression and facilitating more personalized therapeutic strategies. This article aims to provide a structured radiologic interpretation framework based on elementary lesions, their distribution, and their organization into imaging patterns, while addressing common diagnostic pitfalls and incorporating the latest international recommendations.