Despite these advantages, TTE is limited in its ability to evaluate the aortic arch and proximal descending aorta [42,43]. US Echocardiography Transesophageal Transesophageal echocardiography (TEE) can provide views of the descending aorta, but physiologic information derived from these views can be inaccurate [21]. TEE is invasive and may not provide additional information than that gained from TTE [10]. Variant 2: Inflammatory or infectious or neoplastic or metabolic nontraumatic aortic disease. Initial imaging. Aortography Chest and Abdomen Catheter-based aortography provides high spatial and temporal resolution, but because of its invasive nature and inability to detect changes to the vessel wall, it is considered inferior to cross-sectional imaging modalities. For example, a recent meta-analysis found that CT, MRI, and US were better than catheter-based angiography in detecting vascular lesions resulting from Takayasu arteritis [44]. Aortography is of most benefit when an intervention is planned. Overall, the addition of a contrast-enhanced CT scan after an unenhanced CT scan may be of benefit. For suspected vascular infection, one small series found rim enhancement to be the only finding associated with infection that required the administration of IV contrast [45]. Other findings in this series associated with infection did not need Nontraumatic Aortic Disease For suspected vascular infection, CT imaging without IV contrast has some value in identifying signs associated with infection, including perivascular stranding, gas, wall thickening, aneurysmal dilatation, and involvement of adjacent bony structures [45,48]. Similarly, periaortic hemorrhage from ruptured aneurysm can be identified on CT without IV contrast [49]. Benign and malignant aortic tumors are exceedingly rare and often difficult to prospectively diagnose on imaging [50]. For suspected primary vascular neoplasms, an irregular soft-tissue density adjacent to the vessel wall may be seen [46,47].
Nontraumatic Aortic Disease. Despite these advantages, TTE is limited in its ability to evaluate the aortic arch and proximal descending aorta [42,43]. US Echocardiography Transesophageal Transesophageal echocardiography (TEE) can provide views of the descending aorta, but physiologic information derived from these views can be inaccurate [21]. TEE is invasive and may not provide additional information than that gained from TTE [10]. Variant 2: Inflammatory or infectious or neoplastic or metabolic nontraumatic aortic disease. Initial imaging. Aortography Chest and Abdomen Catheter-based aortography provides high spatial and temporal resolution, but because of its invasive nature and inability to detect changes to the vessel wall, it is considered inferior to cross-sectional imaging modalities. For example, a recent meta-analysis found that CT, MRI, and US were better than catheter-based angiography in detecting vascular lesions resulting from Takayasu arteritis [44]. Aortography is of most benefit when an intervention is planned. Overall, the addition of a contrast-enhanced CT scan after an unenhanced CT scan may be of benefit. For suspected vascular infection, one small series found rim enhancement to be the only finding associated with infection that required the administration of IV contrast [45]. Other findings in this series associated with infection did not need Nontraumatic Aortic Disease For suspected vascular infection, CT imaging without IV contrast has some value in identifying signs associated with infection, including perivascular stranding, gas, wall thickening, aneurysmal dilatation, and involvement of adjacent bony structures [45,48]. Similarly, periaortic hemorrhage from ruptured aneurysm can be identified on CT without IV contrast [49]. Benign and malignant aortic tumors are exceedingly rare and often difficult to prospectively diagnose on imaging [50]. For suspected primary vascular neoplasms, an irregular soft-tissue density adjacent to the vessel wall may be seen [46,47].