Blunt cerebrovascular injury in patients with blunt multiple trauma: Diagnostic accuracy of duplex Doppler US and early CT angiography

PURPOSE: To retrospectively evaluate the frequency of blunt cerebrovascular injury (BCVI) in patients with multiple trauma and to retrospectively compare the diagnostic accuracy of duplex Doppler ultrasonography (US) and computed tomographic (CT) angiography by using clinical follow-up and subsequent imaging as reference standards. MATERIALS AND METHODS: The institutional review board approved this study; informed consent was not required. Charts and images of consecutive patients treated for multiple trauma (injury severity score, > 16) between January 1998 and October 2003 were reread by an experienced radiologist. Until October 2002, subjects were screened for BCVI with US. Since November 2002, patients underwent CT angiography of the carotid and vertebral arteries. Sensitivity and specificity of US and CT angiography were calculated with 95% confidence intervals (CIs). RESULTS: The early cohort included 1471 patients (mean age, 35.8 years +/- 17.7 [standard deviation]), and the late cohort included 407 patients (mean age, 39.2 years +/- 18.8). US depicted five blunt vessel injuries but later missed another eight, which led to cerebral ischemia. With a BCVI frequency of 0.9%, sensitivity and specificity of US were 38.5% (95% CI: 13.9%, 68.4%) and 100% (lower 95% confidence limit, 99.7%), respectively. In the second cohort, the BCVI rate was 2.7%. CT angiography depicted BCVI in 11 patients, with a sensitivity of 100% (lower 95% confidence limit, 71.5%), but produced one false-positive result. CONCLUSION: Injuries to the cervical arteries among blunt trauma patients are more common than previously reported. Duplex Doppler US has inadequate sensitivity to help rule out this condition. The notable morbidity with missed dissections warrants routine contrast material-enhanced studies of the carotid and vertebral vessels if patients are scheduled for CT of the cervical spine. (c) RSNA, 2005.