A restrained driver in a high-speed motor vehicle accident was evaluated in the emergency department where he was found to have a Glasgow Coma scale score (GCS) of 6 and significant facial fractures. His injuries were limited to the head, and a computed tomography (CT) scan of the abdomen and pelvis was otherwise negative, and the CT scan of his head showed no intracranial injury. He was admitted and intubated in the intensive care unit (ICU) where he awoke over the next 12 hours. On hospital day 1, he was found to have a new-onset right hemiparesis and aphasia. He was taken for a stat repeat head CT that did not reveal any bleeding but did demonstrate a small left temporal infarct. Angiography showed a left internal carotid artery (ICA) dissection with near-total occlusion in the carotid siphon (Figure 28-1). He was started on antiplatelet therapy (aspirin) and once there was no evidence of bleeding, he was anticoagulated on heparin. Serial head CT scans showed stable infarct size, and he slowly recovered over the next several days.
The typical location of a carotid dissection (shown by the arrow) is at the relatively fixed point of the internal carotid artery (ICA) near the siphon (S-shaped portion as it enters the skull base). This dissection is focal and is only causing about a 30% stenosis. Management would include anticoagulation or possibly antiplatelet agents for 6 months if the patient can tolerate it.
Blunt Carotid Artery Injury
Accounts for 3% to 10% of all carotid injuries.
Overall incidence of carotid artery injury in blunt trauma is 0.08% to 0.33%.
Half of the affected patients show no signs of cervical trauma or neurologic deficit at presentation.
90% of blunt injuries involve the ICA.
The most common location is as it enters the siphon.
Bilateral injury has been reported in 20% to 50% of cases.
There is an increase in the incidence of reported blunt carotid injuries due in part to better recognition and screening (Figure 28-2).
In a more severe dissection there can be complete occlusion of the internal carotid artery. The patient above has a normal common carotid artery (CCA) and external carotid artery (ECA). The internal carotid artery (ICA) has a proximal injury that has led to complete occlusion of the distal ICA.
Penetrating Carotid Injury
The incidence of major vascular trauma following a penetrating injury is 20%.
The low incidence, anatomic site, and variable presentation have made optimal diagnostic and management strategies difficult.
Mechanisms Leading to Blunt Carotid Injury