title: Crescent sign in pulmonary hematoma.
abstract: The pathophysiology of pulmonary hematoma is discussed. The presence of the air-crescent sign in a coin lesion is nonspecific; however, it may direct the attention of the physician to consider a traumatic etiology.
mesh_terms: D006406:Hematoma / Q000209:etiology*; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging / Q000209:etiology*; D055370:Lung Injury; D011859:Radiography; D003074:Solitary Pulmonary Nodule / Q000150:complications