Dissection of the carotid and the vertebral artery

Carotid or vertebral artery dissection describes the separation of the tunica media and tunica intima of a vessel. This can lead to thrombosis of the false lumen, which can, in turn, lead to stenoses or embolisms with the risk of stroke. Dissections of the carotid and vertebral artery primarily affect young adults and may occur spontaneously or as a result of a major trauma (e.g., car accidents). The initial symptoms are usually headaches (temporal and occipital for carotid and vertebral artery dissection respectively), which may be followed by features of ischemia (e.g., stroke) a few hours or days later. Duplex ultrasonography may provide a rapid diagnosis, but definitive diagnosis requires CT angiography or MR angiography. Treatment is primarily conservative and involves blood thinners, anticoagulants, and antiplatelet therapy. Severe cases may require surgery.

• Mean age
  • Carotid artery: 40–45 years ^[1]
  • Vertebral artery: 40 years ^[2]
  • Important causes of stroke in young patients
• Occurrence: Dissection of the carotid artery occurs more frequently than dissection of the vertebral artery (∼ 4:1). ^[3]

Epidemiological data refers to the US, unless otherwise specified.

• Penetrating or blunt trauma, including:
  • High-impact car accidents
  • Mild trauma (e.g., minor sports injuries)
  • Mechanical triggering events (e.g., coughing, sneezing, chiropractic maneuvers)
  • Posterior oropharyngeal injury (especially in children)
• Spontaneous dissection
  • Ehlers-Danlos syndrome and Marfan syndrome
  • Fibromuscular dysplasia
  • Hypertension
  • Cystic medial necrosis
  • Respiratory tract infection
  • Oral contraceptive use

Dissection of the carotid artery

• Non-ischemic features
  • Ipsilateral headache; and facial/neck pain (constant, severe, throbbing or sharp)
  • Partial horner syndrome: ptosis and miosis
  • Pulse-synchronous tinnitus
  • Neck swelling
  • Reduced taste sensation
  • Cranial nerve lesions, usually caudal nerves (VI–XII)
• Ischemic features
  • Symptomatic middle cerebral artery infarction (see “Stroke”)
  • Amaurosis fugax (ischemic retina)

Dissection of the vertebral artery

• Non-ischemic features
  • Occipital headache
  • Posterior nuchal pain
• Ischemic features: vertebrobasilar insufficiency (leads to stroke resembling lateral medullary dysfunction, e.g., Wallenberg syndrome)
  • Ipsilateral loss of taste and facial pain and numbness (most common symptom)
  • Contralateral pain relief and reduced temperature sensation
  • Vertigo
  • Ataxia
  • Central Horner syndrome
  • Dysphagia and dysarthria or hoarseness
  • Nausea, vomiting

Carotid or vertebral artery dissection is the separation of the tunica media and tunica intima of a vessel. This can lead to thrombosis of the false lumen, which can, in turn, lead to stenoses or embolisms with the risk of stroke.

• Duplex ultrasonography: high resistance flow or complete absence of flow in affected artery
• Helical CT angiography (replacing MRI as diagnostic modality of choice ;)
  • Changed caliber of vessel
  • Oval or slit-like cross-section of vessel
• MR angiography
  • Intramural blood
  • Mural expansion
  • Irregular vessel margins
  • Filling defects ^[4]
  • Extravasation of contrast ^[5]
  • Caliber changes of vessel
• Conventional angiography
  • Intimal flap
  • Double lumen
  • Long tapered segment of contrast in distal portion of internal carotid artery

Baseline monitoring parameters (e.g., INR, PT, aPPT) should be performed before administering anticoagulant therapy.

• Treatment should be initiated after an intracerebral hemorrhage has been ruled out.
  • Heparin therapy followed by oral anticoagulation for 3–6 months and/or
  • Antiplatelet agents for 1 year
• Possibly angioplasty/stenting or surgical intervention may be warranted in severe cases

Asymptomatic pseudoaneurysms do not usually require treatment and most dissections heal spontaneously.