PULMONARY hematoma is a traumatically-induced, subacute condition of the lung parenchyma characterized by blood-filled cysts which compress the surrounding parenchyma and alveolar spaces. Forty-one cases of this entity have been fairly well documented in the English literature.
Williams and Bonte1 have contributed the only definitive discussion in any of the standard texts, as distinquished from published case reports in the journals. They state in The Roentgenologic Aspect of Non-Penetrating Chest Injuries that pulmonary hematoma results from extensive hemorrhage into a site of parenchymal laceration and elaborate on the usual course of, events following nonpenetrating chest trauma. The authors stress the chronic nature of pulmonary hematomas, giving 17 weeks as the average time of resolution, and plead for serial roentgenographic study of all chest injuries.
Shanks and Kerley2 mention that "A dense round opacity, a 'hemorrhagic cyst,' occasionally persists after contusion or a penetrating wound of the lung." Other
SPECHT EE. Pulmonary Hematoma. Am J Dis Child. 1966;111(5):559-563. doi:10.1001/archpedi.1966.02090080137017