Blunt Cerebrovascular Injuries (BCVI)

Classic mechanisms of injury

• Carotid artery injury (CAI): Hyperextension of neck resulting in stretching of carotid artery over lateral processes of C1-C3
• Vertebral artery injury (VAI): Fracture through transverse process of C-spine, or hyperextension-stretch injury

Treatment

• Antithrombotic agent (heparin vs aspirin)

Denver Screening Criteria for BCVI

Signs / symptoms of BCVI

• Arterial hemorrhage from neck, nose, or mouth
• Cervical bruit in patients <50 years old
• Expanding cervical hematoma
• Focal neurologic deficit (TIA, hemiparesis, vertebrobasilar symptoms, Horner’s)
• Neurologic exam incongruous with head CT findings
• CVA on CT or MRI

Risk factors for BCVI

• LeFort II or III facial fracture
• C-spine fracture patterns: subluxation, fx extending into transverse foramen, fracture involving C1-C3
• Basilar skull fracture with carotid canal involvement
• Petrous bone fracture
• Diffuse axonal injury with GCS <6
• Near-hanging with anoxic brain injury
• Clothesline type injury or seat belt abrasion with significant swelling, pain, or altered mental status

Imaging Choice

• Gold standard: Digital subtraction angiography
• Accepted first-line imaging: CT angiography (at least 16-slice scanner)
• Alternative: MRI (does not need contrast), may be less sensitive and less specific than CT
• NOTE: A simple seat-belt sign along the neck does not warrant a CT angiogram. Patients with higher risk findings such as significant pain, tenderness, swelling, and/or a bruit may need imaging.

BCVI Grading and Incidence of CVA complication

Grade	Definition	CVA Rate Carotid	CVA Rate Vertebral
1	Irregularity of vessel wall, or dissection/intramural hematoma with <25% luminal stenosis	3%	6%
2	Intraluminal thrombus or raised intimal flap is visualized, or dissection/intramural hematoma with ≥25% luminal narrowing	14%	38%
3	Pseudoaneurysm	26%	27%
4	Vessel occlusion	50%	28%
5	Vessel transection	100%	100%

Risk of undiagnosed BVCI: Delayed CVA

• May occur hours to 14 years later
• Majority develop CVA symptoms in 10-72 hours

References

• Burlew CC, Biffl WL. Imaging for blunt carotid and vertebral artery injuries. Surg Clin N Amer. 2011, 91(1), 217-31 [PubMed]