Question

This CT of the thorax represents:

• A. Ascending aortic dissection
• B. Descending aortic dissection
• C. Aortic aneurysm
• D. Cystic fibrosis

Hint:

An intimal flap with true and false lumens, located beyond the arch.

Answer 1

The Correct Option is B

Step 1: The contrast-enhanced CT of the chest shows an intimal flap within the aorta separating a true and a false lumen, which is the diagnostic feature of aortic dissection. In this case the flap is located in the descending thoracic aorta.

Step 2: Aortic dissection occurs when an intimal tear lets blood track between the layers of the aortic wall, splitting them. CT with intravenous contrast demonstrates the two lumens. The position of the flap distal to the left subclavian, in the descending aorta, defines this as a descending (Stanford type B) dissection (option b).

Step 3: The distractors do not fit. An aneurysm is a focal dilatation without an intimal flap. Ascending dissection would show the flap in the ascending aorta. Cystic fibrosis is a lung disease showing bronchiectasis, not an aortic flap. So descending aortic dissection is correct.