The reported incidence of blunt cerebrovascular injury (BCVI) has increased from approximately 0.1% to 1.0% of patients with closed head/neck trauma, with increased screening of asymptomatic patients. Symptomatic patients will have developed secondary strokes, which are associated with significant morbidity of up to 80% and mortality of up to 40% [56]. There is a variable latent period between vascular injury and symptom onset, with 17% to 36% developing symptoms >24 hours after injury, and when screening appropriately based on clinical or imaging risk factors, approximately 52% to 79% of patients with detected BCVI are asymptomatic [57]. Cerebrovascular injury is also a potential concern in the less common setting of penetrating head/neck trauma. In addition to indirect evidence of arterial injury on prior imaging (eg, hemorrhage or infarct), BCVI has a known association with head/face and cervical fractures. For example, with regard to intracranial arterial injury, positive imaging findings of a skull base fracture that involves the carotid canal or abnormal enlargement of the superior ophthalmic vein and cavernous sinus should prompt evaluation for a petrous or cavernous internal carotid artery injury, respectively [58]. Above the level of the skull base, the branches of the middle and anterior cerebral arteries are often at risk in the setting of penetrating head trauma [30]. Regarding clinical risk factors for BCVI, there are various screening criteria available, which involve tradeoffs in sensitivity (ranging between 63% and 84%) and positive predictive value or screening yield (ranging between 6% and 29%), similar to the clinical decision rules for selective CT scanning in mild head trauma [57]. The 2 original clinical decision rules were the Denver criteria (from University of Colorado) and the Memphis criteria (from University of Tennessee).
Head Trauma PCAs. The reported incidence of blunt cerebrovascular injury (BCVI) has increased from approximately 0.1% to 1.0% of patients with closed head/neck trauma, with increased screening of asymptomatic patients. Symptomatic patients will have developed secondary strokes, which are associated with significant morbidity of up to 80% and mortality of up to 40% [56]. There is a variable latent period between vascular injury and symptom onset, with 17% to 36% developing symptoms >24 hours after injury, and when screening appropriately based on clinical or imaging risk factors, approximately 52% to 79% of patients with detected BCVI are asymptomatic [57]. Cerebrovascular injury is also a potential concern in the less common setting of penetrating head/neck trauma. In addition to indirect evidence of arterial injury on prior imaging (eg, hemorrhage or infarct), BCVI has a known association with head/face and cervical fractures. For example, with regard to intracranial arterial injury, positive imaging findings of a skull base fracture that involves the carotid canal or abnormal enlargement of the superior ophthalmic vein and cavernous sinus should prompt evaluation for a petrous or cavernous internal carotid artery injury, respectively [58]. Above the level of the skull base, the branches of the middle and anterior cerebral arteries are often at risk in the setting of penetrating head trauma [30]. Regarding clinical risk factors for BCVI, there are various screening criteria available, which involve tradeoffs in sensitivity (ranging between 63% and 84%) and positive predictive value or screening yield (ranging between 6% and 29%), similar to the clinical decision rules for selective CT scanning in mild head trauma [57]. The 2 original clinical decision rules were the Denver criteria (from University of Colorado) and the Memphis criteria (from University of Tennessee).