Abstract
We report the incidental finding of a late post-traumatic pseudoaneurysm of the thoracic aorta in a patient being treated for subarachnoid hemorrhage from a motorcycle accident. The diagnosis of calcified vascular mediastinal masses may be suspected from routine chest roentgenograms and confirmed by aortography. Computed tomography and magnetic resonance imaging are helpful when the diagnosis remains obscure. The recognition of chronic pseudoaneurysms is clinically important.