Aortic pseudoaneurysm versus ductus diverticulum

Differentiation of aortic pseudoaneurysm from ductus diverticulum is critical, particularly in the trauma setting. A traumatic aortic pseudoaneurysm is a surgical emergency whereas a ductus diverticulum is a normal anatomic variant.

The following are differentiating features:

Aortic pseudoaneurysm

  • location: often seen along the inferior surface of the aortic isthmus 
  • angle with the aortic wall: acute angle
  • calcification: not present
  • other supportive findings: signs of regional traumatic injuries such as an intimal flap or hematoma nearby within the aortic wall and/or mediastinum

Ductus diverticulum

  • location: usually found at the anteromedial aspect of the aortic isthmus 
  • angle with the aortic wall: often gentle, obtuse angle 
  • calcification: an important differentiating point when present
  • absence of other supportive findings