Mediastinal bronchial artery aneurysm: dynamic computed tomography appearance.

Mediastinal aneurysms of the bronchial arteries are uncommon abnormalities with potentially fatal hemorrhagic complications. Their diagnosis is usually made by angiography in emergency situations but computed tomography (CT) scan may depict them in asymptomatic patients. We describe the CT appearance of such an aneurysm detected as an incidental finding in a patient with bleeding bronchiectasis.