Value of CT in determining the need for angiography when findings of mediastinal hemorrhage on chest radiographs are equivocal

The role of CT in determining the need for angiography in patients with possible thoracic vascular injury resulting from blunt trauma is controversial. During a 24-month period, we prospectively evaluated the results of CT to screen 90 patients with a history of decelerating thoracic trauma for evidence of mediastinal hemorrhage or great vessel abnormality. All patients either had equivocally abnormal mediastinal contours on chest radiographs (64%) or had technically suboptimal chest radiographs owing to body habitus or restriction to the supine projection (36%). Patients with unequivocal signs of mediastinal hemorrhage on chest radiographs underwent immediate arteriography without prior CT. Thoracic CT was interpreted as normal in 63 (77%) patients and no further imaging was performed. Five patients had technically suboptimal CT studies, and CT scans were interpreted as equivocal in six. These 11 patients had normal arteriograms. Sixteen CT scans (18%) demonstrated evidence of mediastinal hemorrhage and/or great vessel contour abnormality. Four (27%) of 15 patients who underwent arteriography had injury to the great vessels. One patient refused to undergo angiography. In 11 patients with CT evidence of mediastinal hemorrhage, major vascular injury was not seen on arteriography. These results suggest a valuable role for CT in determining the need for arteriography to detect potential great vessel injury in patients with blunt decelerating thoracic trauma and equivocally abnormal mediastinal contours on chest radiographs.