471 Prospective Comparison of CT and Digital Subtraction Angiography to Diagnose Penetrating Cerebrovascular Injuries: Preliminary Data

Abstract

INTRODUCTION: Digital subtraction angiography (DSA) is the gold standard for detecting penetrating cerebrovascular injuries, but CT angiography (CTA) is often used. Few studies compare CTA and DSA for this indication and are retrospective, which indicate sensitivity of CTA is about 70%. METHODS: Prospective observational cohort study of all patients with penetrating head injuries at Harborview Medical Center, excluding patients with unsalvageable injuries. CTA of the head was performed immediately after presentation, followed by 6 vessel DSA within 48 hours. Sensitivity and specificity of CTA compared to DSA were then calculated. RESULTS: Enrollment is ongoing. 14 patients have undergone CTA and DSA of whom 7 have cerebrovascular injury. Of these CTA missed pathology seen on DSA in 4 cases, yielding sensitivity of 43%, all cases missing dural-arteriovenous or carotid-cavernous fistulae. In one case a small pseudoaneurysm was called on CTA that was not seen on DSA, yielding specificity of 86%. CONCLUSION: Early findings suggest that CTA is at least as insensitive for penetrating cerebrovascular injury as suggested by retrospective studies. This insensitvity is particularly relevant in cases of traumatic fistulae. More data are needed, and enrollment of subjects is ongoing at our center and at collaborating institutions.