Diagnostic value of the helical CT scan for traumatic aortic injury: correlation with mortality and early rupture.

To evaluate the value of helical computed tomography of the thorax (HCTT) as a definitive tool for diagnosing traumatic aortic injury, this study retrospectively examined 53 patients with blunt thoracic injuries and HCTT during a 5-year period. All CT scans were reviewed for direct signs of aortic injury and correlated with aortography or surgery. Correlations between clinical parameters, as well as combinations of direct signs and individual signs, and mortality were analyzed in all traumatic aortic injury (TAI) cases. Direct signs were seen on the HCTT in 25 cases and 22 had TAI. All false positive results came from the group with only a single direct sign depicted on HCTT. Among individual direct signs examined, intimal flap and luminal thrombus were the most specific (100%), whereas irregular aortic contour was the most sensitive (100%). A combination of > or = 3 direct signs (p = 0.006) and periaortic contrast material extravasation significantly correlated with early rupture and mortality (p = 0.002). In conclusion, intimal flap on HCTT is both the most specific and sensitive sign for TAI. TAI patients with > or = 3 direct signs, including periaortic contrast material extravasation, may not require aortography before immediate surgery.