Which of the following confirms the diagnosis of transection of the descending thoracic aorta?

D. Positive aortogram.

DISCUSSION: The diagnosis of transected aorta should be suspected with severe injury especially if the patient is thrown from the vehicle. A widened mediastinum, fractured first rib, or a pleural effusion can each be seen with chest trauma that does not involve the thoracic aorta. The diagnosis is best made by the use of the aortogram even though the diagnosis can be made with CT, MRI, and occasionally echocardiography.