Traumatic vertebral artery injury: a review of the screening criteria, imaging spectrum, mimics, and pitfalls

PURPOSE: Traumatic vertebral artery injury (TVAI) can have a varied clinical presentation and appearance on imaging. In this review, we present the screening criteria, spectrum of imaging features, grading, and imaging pitfalls of TVAI. Our review focuses on the imaging of TVAI on computed tomography angiography (CTA), magnetic resonance angiography (MRA), and cases of TVAI mimics. IMAGING: The imaging spectrum on CTA can range from either focal or long segment luminal stenosis (the most common findings), smooth or tapered narrowing of lumen, string of pearls appearance, concentric intramural haematoma, intimal flap (the most definite sign), and double lumen of the artery. On time-of-flight MRA, the most common findings include loss of flow void within the vessel due to slow flow, thrombosis or occlusion, and hyperintense signal within the vessel wall due to intramural haematoma on T1 fat-saturated images. CONCLUSION: The reader should be aware of the screening criteria, common and uncommon findings, variant anatomy, artifacts, and mimics of TVAI when evaluating cases of craniocervical trauma, to be competent in calling in or ruling out injury.