Minimal aortic injury

Dr Vincent Tatco et al.

Minimal aortic injuries are traumatic aortic lesions that usually involve the intima and are recognised more frequently due to the use of high-resolution imaging.

Minimal aortic injuries account for 10-28% of all blunt traumatic aortic injuries 1,6,7. The proportion of this type of aortic injury among overall blunt traumatic aortic injuries is higher in more recent studies due to the widespread use of multidetector computed tomography (MDCT) for trauma emergencies.   

Minimal aortic injuries are mild forms of blunt traumatic aortic injury.  Various definitions of minimal aortic injury have been used in literature. They were originally defined as small (<1 cm) intimal flaps with no or minimal periaortic haematoma. Some authors defined the lesions as post-traumatic abnormalities of the inner aortic wall projecting into the lumen with no evidence of an abnormality to the outer contour of the aorta.

Like other blunt traumatic aortic injuries, proposed mechanisms include:

  • rapid deceleration
  • shearing forces
  • osseous pinch
  • sudden increase in hydrostatic forces or water-hammer phenomenon

Injuries limited to the intimal layer usually do not compromise the resistance of the aortic wall and may heal spontaneously by endothelialization.

Most minimal aortic injuries occurred in the descending thoracic aorta, particularly the proximal portion called the aortic isthmus

CT angiography is the investigation of choice. With improvements in imaging technology, which allow a thinner CT slice thickness, minimal aortic injuries are being diagnosed more frequently.

Minimal aortic injuries can present with:

  • intimal irregularity or flap
    • most common imaging appearance (~80%) 1
    • rounded, triangular or focal thin membrane-like filling defects
  • intraluminal aortic thrombus
  • intramural haematoma (~10%) 1

Since intimal injuries may resolve spontaneously, minimal aortic injuries are amenable to non-operative or medical management and can be treated conservatively with anti-hypertensives, anticoagulants or both depending on the coexisting injuries. Limited data on the natural history of this type of aortic injury necessitates close imaging surveillance for detection of any potential complication or adverse evolution of the minimal aortic injury. In some institutions, endovascular repair is another option for treatment.

Normal anatomic variants and conditions that can mimic minimal aortic injuries on CT include:

  • breathing, arterial pulsation and other motion artefacts
  • streaming of contrast
  • ductus diverticulum and ductus remnant
  • infundibulum of branch vessel
Share article

Article information

rID: 55840
Systems: Vascular, Chest, Trauma
Tag: cases
Synonyms or Alternate Spellings:
  • Minimal aortic injuries
  • Minimal injury of the aorta
  • Minimal injuries of the aorta
  • Minimal aortic injury (MAI)
  • Minimal aortic injuries (MAIs)
  • MAI
  • MAIs
  • MAI's

Support Radiopaedia and see fewer ads

Cases and figures

  • Drag
    Figure 1: illustration
    Drag here to reorder.
  • Drag
    Case 1
    Drag here to reorder.
  • Drag
    Case 2
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.