Role of computed tomography and magnetic resonance imaging in assessment of acute aortic syndromes.

Acute aortic syndromes refer to the spectrum of aortic emergencies that include nontraumatic diseases of the aorta, such as aortic dissection, intramural hematoma, penetrating atherosclerotic ulcer, aortic aneurysm leak, as well as traumatic aortic transection. Patients presenting with nontraumatic acute aortic syndromes usually have a similar clinical profile; hence, clinical diagnosis is difficult. Computed tomography (CT) and magnetic resonance imaging (MRI) allow for specific diagnosis of the underlying condition. Traumatic rupture of the aorta is one of the most dreaded complications of blunt chest trauma; therefore, in patients with high-risk deceleration injuries, radiographic assessment of the aorta is crucial. Imaging methods should detect even subtle aortic wall disruption and should provide a mechanism for communicating the findings to the surgical team. Noninvasive, cross-sectional imaging techniques have proven efficacy in the diagnosis of aortic pathology and have largely replaced aortography. Both CT and MR imaging provide aortogram-like reconstruction of the original data sets, and in addition to assessing the aortic lumen, permit detailed evaluation of the aortic wall, as well as comprehensive assessment of thoracic and abdominal viscera. This article addresses the role of different imaging modalities in assessment of acute aortic syndromes, with focus on CT and MRI, and with discussion of the key imaging findings that allow distinction among the various aortic pathologies.