<unk>  is rarely used in the modern era. It can be used of the other imaging modalities are not available or are inconclusive.
Aortic dissection aortography
Thoracic aortic aneurysm CT
Aortic dissection physical examination
Abdominal aortic aneurysm ultrasound
Superior vena cava syndrome ultrasound
Fat embolism syndrome CT
Traumatic aortic rupture chest x ray
Thoracic aortic aneurysm MRI