Analysis of Extracranial Cerebrovascular Injuries: Clinical Predictors of Management and Outcomes.

OBJECTIVE: Optimal management of traumatic extracranial cerebrovascular injuries (ECVI) remains undefined. We sought to evaluate the factors that influence management, and neurologic outcomes (stroke and brain death) following traumatic ECVI.

METHOD: A retrospective review of a single level 1 trauma center's prospectively maintained data registry of patients older than 18 years of age with a diagnosis of ECVI was performed from 2013-2019. Injuries limited to the external carotid artery were excluded. Patient demographics, type of injury, timing of presentation, Biffl Classification of Cerebrovascular Injury Grade, Injury Severity Score (ISS), and Abbreviated Injury Scale (AIS) were documented. Ultimate treatments (medical management, procedural interventions) and brain-related outcomes (stroke and brain death) were recorded.

RESULTS: ECVI were identified in 96 patients. The primary mechanism of injury was blunt trauma (89.5% vs 10.5%, blunt vs penetrating), with 70 cases (66%) of vertebral artery injury and 37 cases of carotid artery injury. Treatments included vascular intervention (6.5%) and medical management (93.5%). Overall outcomes included ipsilateral ischemic stroke (29%) and brain death (6.5%). In the carotid group, vascular intervention was associated with higher Biffl grades (mean Biffl 3.17 vs. 2.23; p = 0.087) and decreased incidence of brain death (0% vs 19%, p=0.006), with no difference seen in ISS scores. Brain death was associated with higher ISS scores (40.29 vs. 24.17, p=0.01), lower GCS on arrival (3.57 vs. 10.63, p<0.001), and increased rates of ischemic stroke (71% vs. 30%, p=0.025). In the vertebral group, neither Biffl grade nor ISS were associated with treatment or outcomes. Regarding the timing of stroke in ECVI, there was no significant difference in the time from presentation to cerebral infarction between the carotid and vertebral artery groups (24.7 hours vs. 21.20 hours, p=0.739). After this window, 98% of the ECVI cases demonstrated no further aneurysmal degeneration or new neurological deficits beyond the early time period (mean follow up 9.7 months).

CONCLUSION: Blunt cerebrovascular injuries should be viewed distinctly in the carotid and vertebral territories. In cases of injury to the carotid artery, Biffl grade and ISS score are associated with surgical intervention and neurologic events respectively; vertebral artery injuries did not share this association. Neurologic deficits were detected in a similar time frame between the carotid artery and the vertebral artery injury groups and both groups had rare late neurologic events.