Chapter30 Aorta

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Section V: Cardiac Radiology

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Figure 30.42.  Descending Aortic Pseudoaneurysm Complicated by Aortobronchial Fistula and Pulmonary Hemorrhage. Coronal CT image ( A ) demonstrates the irregular margins of the pseudoaneurysm ( P, white arrows ) with adjacent hematoma (*). The neck of the pseudoaneurysm is narrower than the pseudoaneurysm itself. Air ( yellow arrow ) adjacent to the hematoma represents sequela of an aortobronchial fistula. Coronal CT image at the same level using lung algorithm ( B ) demonstrates the adjacent consolidative, reticular and ground-glass opacities representing pulmonary hemorrhage ( H ).

phy is almost invariably performed as part of the workup for trauma patients; while it is limited in sensitivity and speci- ficity and often performed using portable technique, it may demonstrate superior mediastinal widening, apical cap, and/ or loss of the normal aortic knob or descending aortic contour (Fig. 30.46). Positive findings on radiography and/or high clini- cal suspicion should prompt further imaging. Prior to the advent of modern CT scanners, direct catheter angiography was the pre- ferred method at many trauma centers, with the ability to diag- nose and treat with endovascular techniques in the same setting. However, CT has mostly supplanted angiography as a primary imaging modality, except in certain limited circumstances—

is a rapid deceleration injury in the setting of motor vehicle accident. The exact mechanism of injury is not known but may result from shearing forces and/or an “osseous pinch” between the manubrium and thoracic spine; the most com- mon sites of injury are those of maximum traction: the aortic root, the aortic isthmus, and much less commonly the aorta at the level of the diaphragmatic aortic hiatus. While survival rates for those with isthmus injuries have improved over the past few decades, those with injuries located at the aortic root rarely survive. Aortic injury with pseudoaneurysm is often asymptomatic; imaging is therefore key in rapid diagnosis. Chest radiogra-

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Figure 30.43.  Ascending Aorta Pseudoaneurysm. Axial-oblique CT image at the time of presentation ( A ) demonstrates two narrow-necked pseudoaneurysms ( P ) along the ascending aorta. There is associated hemopericardium (*) causing pericardial inflammation ( white arrows ). The patient adamantly refused treatment and returned 3 months later with severe chest pain. Axial-oblique ( B ) and coronal-oblique ( C ) CT images demonstrate marked interval increase in size of the pseudoaneurysm ( P ). In addition to hemopericardium (*), there is now blood in the medias- tinum ( white arrows ).