The role of contrast-enhanced spiral CT imaging versus chest X-rays in surgical therapeutic concepts and thoracic aortic injury: a 29-year Swiss retrospective analysis of aortic surgery.

BACKGROUND: Blunt chest trauma accounts for 90% of chest trauma in the civilian population in Europe and the United States and causes 20% of trauma-related deaths. Missed aortic injuries can rupture and lead to subsequent death of the patient.

MATERIALS AND METHODS: This retrospective study compared two different imaging strategies, chest X-rays compared to additional contrast-enhanced spiral CT imaging, in patients suffering from blunt thoracic trauma. The study also questioned whether the additional information obtained from CT scans changed further surgical therapeutic concepts or the decision for immediate surgery.

RESULTS: Between 1971 and 2001, 39 patients were detected with thoracic trauma and aortic lesions. Of the 28 patients who underwent initial CT scanning, 12 (31%) had an emergency thoracotomy (sternotomy) performed on them, which the other 16 did not require. In four (10%) of these 16 patients, the aorta was stabilised and a possible leak was covered with endovascular stenting. In another eight (21%) of them, the concomitant injuries were initially treated and, following regular check-ups, an elective repair of the aortic lesion was performed after a number of months. In four (10%) patients with intramural haematomas or minor leakage, no intervention was necessary. Eleven (28%) patients did not have a chest CT scan on admission and the diagnosis of a contained aortic rupture was missed. They were readmitted to the hospital between four months and 29 years after the initial accident with symptomatic posttraumatic pseudo-aneurysm of the thoracic aorta.

CONCLUSIONS: We believe that helical CT evaluation of the mediastinum should be performed in all patients who undergo blunt thoracic trauma, irrespective of chest radiographic findings. Missed diagnoses can occur after angiography or ultrasound alone, and false-positive diagnoses can also be made. Following the current literature, we therefore recommend a primary routine chest CT scan in all patients with a history of motor vehicle accident (MVA) at a speed of more than 16 km/h (unrestrained) or 48 km/h (restrained). Furthermore, we recommend a CT scan even if the height fallen was as little as seven metres.