Ruptured thoracic aneurysm: unusual manifestation and early diagnosis using CT.

Rupture of a thoracic aortic aneurysm across the posterior mediastinum into the right side of the chest is rare. The diagnosis may be delayed by the absence of expected findings in the left side of the chest. We recently encountered two patients with thoracic aneurysm rupture who came to medical attention initially because of right-sided pleural and/or extrapleural hematomas, which were accurately diagnosed preoperatively on the basis of computed tomography (CT) findings. Aortography, performed in one patient, added no useful information. Because CT accurately identifies the presence of pleural or extrapleural blood, as well as the underlying aneurysm or dissection, CT should be the first examination performed in cases of suspected thoracic aneurysm rupture.