Phenotyping pulmonary sarcoidosis

Pulmonary sarcoidosis, although generally associated with a good prognosis, remains challenging to manage in view of its unpredictable disease behaviour and outcome. Being able to phenotype patients with sarcoidosis could potentially facilitate treatment decisions and promote research anchored to disease behaviour and outcome. Efforts to phenotype sarcoidosis using imaging date back to the early 1900s when chest X-rays were the main modality for lung parenchymal evaluation. However, despite significant advances in technology, there is currently no consensus on how we should classify this disease utilizing more modern imaging techniques. In this review, we provide an overview of imaging phenotypes in sarcoidosis, discuss the challenges of disease classification, evaluate associations between imaging appearance and outcome, and explore new developments in this field.