From X-rays to advanced imaging modalities in pulmonary sarcoidosis

Sarcoidosis is a multisystem inflammatory disorder characterized by noncaseating epithelioid granulomata, most commonly involving the lungs and thoracic lymph nodes. Although definitive diagnosis relies on tissue biopsy, characteristic findings detected on computed tomography (CT) often allow a confident diagnosis. Atypical imaging patterns, however, can complicate differentiation from other diseases. Different high-resolution CT phenotypes of pulmonary sarcoidosis have been recently defined by the multinational Delphi consensus study, aiming at providing a basis for the development of a formal classification of pulmonary sarcoidosis. Chest CT plays a central role in the diagnosis and follow-up, complemented by magnetic resonance imaging and nuclear imaging, while quantitative approaches have shown promise in enhancing the evaluation of pulmonary sarcoidosis. This review focuses on the role of imaging in pulmonary sarcoidosis, highlighting both typical and atypical radiological manifestations.