Blunt cerebrovascular injury

Background

• BCVI includes: intimal flap/dissection, intramural hematoma, pseudoaneurysm, occlusion, and transection of the carotid or vertebral arteries
• ~50% of BCVI-related strokes occur before hospital arrival; the other half are preventable with screening and early treatment
• Carotid and vertebral arteries are equally affected; carotid injuries carry higher mortality
• Even with screening criteria, ~20% of BCVI may be missed — some institutions now advocate universal CTA of the neck in all significant blunt trauma
• Blunt cerebrovascular injury (BCVI) is a non-penetrating injury to the carotid and/or vertebral arteries that may be clinically silent initially but can cause devastating stroke if not identified and treated.
• Incidence is 1-2% of blunt trauma admissions but up to 9% in severe head injury.
• Screening with the Denver Screening Criteria and CTA has reduced the stroke rate from ~15% to <1% in asymptomatic patients.

Clinical Features

• Most patients are asymptomatic at initial presentation — this is why screening is critical
• Symptomatic patients may present with:
  • Acute stroke symptoms (hemiparesis, aphasia, facial droop) — may be delayed hours to days after injury
  • Expanding cervical hematoma
  • Arterial hemorrhage from neck, nose, or mouth
  • Cervical bruit in a young patient (uncommon but specific)
  • Horner syndrome (ptosis, miosis, anhidrosis) — from carotid dissection disrupting sympathetic fibers
  • Neurologic deficit inconsistent with CT head findings — think BCVI if stroke territory doesn't match the head injury pattern

Differential Diagnosis

Neck Trauma

• Penetrating neck trauma
• Blunt neck trauma
  • Vertebral and carotid artery dissection
  • Strangulation
  • Whiplash injury
• Cervical injury
  • Cervical fractures and dislocations
  • Cervical injury (peds)
  • Cervical spine clearance
• Neurogenic shock
• Spinal cord injury

Evaluation

Workup

• Apply Modified Denver Screening Criteria — obtain CTA if ANY ONE is present:

Signs/symptoms:

• Arterial hemorrhage from neck/nose/mouth
• Cervical bruit in patient <50 years
• Expanding cervical hematoma
• Focal neurologic deficit (TIA, hemiparesis, Horner syndrome)
• Neurologic deficit inconsistent with head CT findings
• Stroke on CT or MRI

Risk factors (injury pattern):

• Cervical spine fracture (any level, excluding isolated spinous/transverse process fractures)
• C1-C3 fracture, subluxation, or ligamentous injury
• Fracture through the transverse foramen
• Le Fort II or III facial fractures
• Basilar skull fracture involving the carotid canal
• Diffuse axonal injury with GCS <6
• Near-hanging or strangulation with anoxic brain injury
• Mandible fractures
• Complex skull fractures
• Scalp degloving
• Thoracic vascular injury
• Blunt cardiac rupture

• CTA of the neck (from aortic arch through circle of Willis): imaging modality of choice; sensitivity/specificity ~98%/100% with modern ≥16-slice CT
• Do NOT wait for symptoms to image — the whole point is to screen asymptomatic patients before they stroke

Diagnosis

• Biffl Grading Scale (determines management):

Grade	Injury	Stroke risk
I	Intimal irregularity or dissection with <25% luminal narrowing	Low
II	Dissection/intramural hematoma with ≥25% luminal narrowing, intraluminal thrombus, or raised intimal flap	Moderate
III	Pseudoaneurysm	Moderate-high
IV	Complete occlusion	High
V	Transection with active extravasation	Highest; hemorrhagic emergency

• Many grade I-II injuries heal spontaneously within 7-10 days with antithrombotic therapy
• Follow-up CTA at 7-10 days is standard to reassess injury progression or healing

Management

• Start antithrombotic therapy (ATT) as soon as safely possible — this is the single most important intervention to prevent stroke
  • ATT reduces stroke risk: OR 0.20 (80% reduction) and mortality: OR 0.17
• Preferred antithrombotic regimens:
  • Aspirin 325 mg daily — most commonly used; simplest; adequate for most grade I-II injuries
  • Aspirin + clopidogrel — used at some centers for higher-grade injuries
  • Heparin infusion (target PTT 40-50) — alternative, especially if higher-grade injury or concern for thrombus progression
• When ATT is contraindicated (intracranial hemorrhage, solid organ injury, other active bleeding):
  • Discuss with trauma surgery/neurosurgery — risk-benefit must be weighed case by case
  • Some centers delay ATT 24-72 hours until bleeding risk stabilizes; others accept the stroke risk temporarily
  • Do not simply omit ATT without a documented plan — untreated BCVI has a 21% stroke rate
• Grade V (transection with active hemorrhage): emergent hemorrhage control — direct pressure, emergent endovascular intervention, or operative repair
• Grade III-IV: ATT ± endovascular stenting (decision made by vascular surgery/interventional radiology at follow-up; not an ED decision)
• Consult: trauma surgery, and as needed neurosurgery and/or vascular surgery/interventional radiology

Disposition

• All patients with confirmed BCVI: admit to trauma service with serial neurologic examinations
• Start ATT in the ED if no contraindication — do not defer to the floor
• Follow-up CTA at 7-10 days — document this plan; many grade I-II injuries resolve; grade III+ may progress and require intervention
• If screening criteria are met but CTA is negative: admit the trauma patient per standard protocols; a negative CTA has very high NPV — no further BCVI-specific follow-up needed unless new neurologic symptoms develop
• Document clearly: Denver screening criteria met, CTA result, Biffl grade if positive, ATT initiated (and agent/dose), and follow-up imaging plan

See Also

• Vertebral artery dissection
• Carotid artery dissection
• Penetrating neck trauma
• Cervical fractures and dislocations
• Strangulation
• Stroke
• Traumatic brain injury

External Links

• EAST — Blunt Cerebrovascular Injury Practice Management Guideline (2020)
• Scand J Trauma — Best practice guidelines for BCVI (2018)
• AJNR — Blunt Cerebrovascular Injuries: Advances in Screening, Imaging, and Management (2021)
• EMRA — A Review of Blunt Cerebrovascular Injuries