Screening for blunt cerebrovascular injury: evaluating the accuracy of multidetector computed tomographic angiography

BACKGROUND: Digital subtraction angiography (DSA) has been widely considered the "gold standard" for diagnosing blunt cerebral vascular injury, but recent advances in multidetector computed tomographic angiography (CTA) may have led to improved accuracy compared with DSA. METHODS: A retrospective study of patients who underwent CTA and DSA for suspected blunt cerebral vascular injury was performed. Two neuroradiologists and one radiology resident, blinded to the other test, independently reviewed CTA and DSA studies. Sensitivity and specificity of CTA were determined using DSA as the gold standard. RESULTS: Thirty-two patients met the study criteria. Consensus DSA interpretation identified 17 vascular injuries in 15 patients. Among the three radiologists, the sensitivity of CTA for carotid injury ranged from 83% (10 of 12) to 92% (11 of 12), and the specificity ranged from 88% (36 of 41) to 98% (40 of 41). The sensitivity for vertebral artery injury ranged from 40% (2 of 5) to 60% (3 of 5), and the specificity ranged from 90% (35 of 39) to 97% (38 of 39). CTA sensitivity rose to 80% (four of five) in the vertebral artery when a lower diagnostic threshold was used. CONCLUSION: The sensitivity of CTA for carotid artery injury at our center was higher than in previous studies. This might be attributable to the superior quality of multidetector CTA images. Our conclusions on CTA accuracy in the vertebral artery are limited by the small number of injuries.