Imaging Sciences Interesting Cases
Case 350
Nate Johnson, MD
Clinical Presentation: Patient is an 18-year-old male presenting status post-motor vehicle crash.
Imaging Findings: A 2.4 x 1.3 cm outpouching on the lateral side of the thoracic aorta just distal to the left subclavian artery takeoff.
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| Figure 1. Coronal reformat CT. |
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| Figure 2: Axial CT. |
Diagnosis: Traumatic pseudoaneurysm of the aortic arch
Discussion: Aortic injury is one of the most life threatening injuries that one may encounter. Eighty-five percent of these patients exsanguinate before reaching the hospital. Without intervention 80% of patients will die within one hour and 98% will die at 10 weeks.
Contrast enhanced CT with thin sections and multiplanar reformats is nearly 100% accurate in identifying aortic injury. Findings include: 1) Pseudoaneurysm; 2) Intimal flap; 3) Altered aortic contour; 4) Filling Defect; and 5) Rarely extravasation (patient likely would not have survived.)
Most common location for injury in CT: 1) Aortic isthmus (88%); 2) Aortic Arch with avulsed brachiocephalic (4.5%); 3) Descending Aorta (2%); and 4) Ascending Aorta (1%). Please note that ascending aortic tears are much more common overall than 1%, but patients rarely survive to obtain CT scan.
References:
- Jeffrey RB. Diagnostic Imaging: Emergency. Amirsys, 2007.
- Gurney JD. Diagnostic Imaging: Chest. Amirsys, 2006.