Images and case Danielle Martinez
An 89 year old lady presented to hospital with severe abdominal pain and collapse on a background of a known AAA. On arrival, she was hypotensive and pale with a reduced level of consciousness.
A Point of Care Ultrasound was performed. A shows a transverse view through the mid aorta. B AP diameter of mid aorta. C a longitudinal view of the proximal abdominal aorta. D a longitudinal view of the mid aorta. E a longitudinal view of the distal aorta.
Describe the following scans. At which point is an aorta considered aneurysmal? Why is there thrombus within the cavity of the aorta?
A 
B 
C 
D 
E 
- There is a large AAA measuring 6.7 cm.
- The measurement is made outer wall to outer wall
- A AAA of > 3cm is considered aneurysmal
- There is significant hypoechoic thrombus within the aorta suggesting there may be liquefication of the thrombus.
- The aneurysm extends from the proximal to the distal aorta
- A AAA often has thrombus hugging its wall as flow through an aneurysmal aorta is not laminar. The echogenicity of the thrombus will depend on it’s age and the degree of organization of the layers within the thrombus.
Note that the risk of rupture increases with the size of the aneurysms
AAA diameter (cm) Rupture risk (%/year)
4.0–4.9 1%
5.0–5.9 1–10%
6.0–6.9 10–22%
>7.0 30–50%
AFP 2013 June Aortic aneurysms Screening, surveillance and referral Domenic Robinson Barend Mees Hence Verhagen Jason Chuen
This is a scan of her mid aorta with colour. What can you see?
There is colour extravasation through the wall of the aorta at 11 o’clock. Adjacent to this there is a hypoechoic para-aortic area which is coagulated blood
Is it likely that you will see a rupture of a AAA on ultrasound ?
It is rarely possible to see a rupture of a AAA on ultrasound because AAA’s usually rupture in the retroperitoneal space where ultrasound visualization is limited. The case presented here is unusual
In 2005, Catalano described 8 characteristics on ultrasound suggestive of a rupture
- Deformation of aneurysmal shape
- Inhomogeneous appearance of the luminal thrombus
- Focal discontinuity of the thrombus layer
- A floating intraluminal thrombus layer
- Focal disruption of the outer aneurysmal wall
- A para-aortic hypoechoic area
- Retroperitoneal hematoma
- Hemoperitoneum
After discussions with vascular surgery, ED and the patient’s family, a decision was made to palliate the patient and she passed away in the ED the focus being on pain relief for this patient
References
- Ruptured abdominal aortic aneurysm identified on point-of-care ultrasound in the emergency department Omar Diaz & Wesley Eilbert
International Journal of Emergency Medicine volume - Catalano O, Lobianco R, Cusati B. Contrast-enhanced sonography for diagnosis of ruptured abdominal aortic aneurysm. AJR Am J Roentgenol. 2005;184(2):423–7.
- AFP 2013 June Aortic aneurysms Screening, surveillance and referral Domenic Robinson Barend Mees Hence Verhagen Jason Chuen