Evaluating the Role of Imaging Markers in Predicting Stroke Risk and Guiding Management After Vertebral Artery Injury: A Retrospective Study

BACKGROUND AND PURPOSE: Traumatic vertebral artery injury is a severe consequence of head and neck trauma occurring when a disturbance to vessel wall architecture causes vessel dissection. These injuries come with a host of complications, including debilitating neurological damage, although patients are often asymptomatic upon presentation. Still, the screening recommendations, treatment strategies, and predicted outcomes of traumatic vertebral artery injury remain largely undefined. Therefore, it is imperative to investigate the risk of life-threatening sequelae occurring secondary to vertebral artery injury to minimize patient morbidity. This study aimed to explore the Biffl grade as an imaging marker for prognosticating acute stroke risk and guiding appropriate management strategies. We hypothesize that an increase in Biffl grade will directly correlate with an increase in post-injury stroke risk in a stepwise fashion.

MATERIALS AND METHODS: A database of patients admitted to a level 1 trauma center with CTA-diagnosed vertebral artery injury was retrospectively reviewed. The primary outcome was the risk of an acute ischemic stroke event within 14 days of injury. Univariable and multivariable logistic regression analyses were performed to explore the association between Biffl grade and stroke risk while controlling for clinically significant covariables.

RESULTS: Of 219 patients, the median age was 60 years. Within the acute period, 22 (10.0%) of traumatic vertebral artery injury patients had an acute stroke. In the multivariable regression, only Biffl Grade 2 (p=0.01) and 4 (p=0.04) were significantly associated with a higher risk of stroke. This risk did not increase in a stepwise fashion as Biffl grade increased. The predicted probability of a stroke event exceeds 20% for Biffl grade 2 and 5 injuries, and the probability of stroke decreases in patients managed with antithrombotic medication regardless of injury severity.

CONCLUSIONS: The risk of post-injury ischemic stroke does not consistently correlate with injury severity as assessed per the Biffl grade. Thus, Biffl grade alone is likely not an adequate prognostic factor to predict the risk of ischemic stroke in traumatic vertebral artery injury patients or for guiding optimal treatment for such patients with increased risk for stroke.

ABBREVIATIONS: TVAI = traumatic vertebral artery injury; IQR = interquartile range; GCS = Glasgow Coma Scale; DAPT = Dual Antiplatelet Therapy.