Carotid artery dissection
Carotid artery dissection is a tear in the wall of the internal carotid artery creating an intramural hematoma, typically presenting with unilateral head, face, or neck pain, partial Horner syndrome, and ischemic stroke or transient ischemic attack in a young or middle-aged patient. Diagnosis is by MRA or CTA of the neck, and most patients are treated with antiplatelet or anticoagulant therapy.
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What this article covers
- Overview
Definition: carotid artery dissection is a tear in the wall of the internal carotid artery, most often extracranial, that allows blood into the media and creates an intramural hematoma (false lumen)…
- Epidemiology
Young stroke etiology: extracranial carotid and vertebral artery dissection together account for a substantial proportion of ischemic strokes in adults younger than 50, making dissection one of the…
- Risk factors
Connective tissue disorders: heritable disorders of collagen or elastin (such as vascular Ehlers-Danlos syndrome and Marfan syndrome) predispose to spontaneous arterial wall tears.
- Pathophysiology
Site of injury: a tear (spontaneous or traumatic) develops in the arterial wall, most commonly in the extracranial internal carotid artery a few centimeters distal to the carotid bifurcation.
- Clinical features
No fixed diagnostic criteria; recognized by the clinical triad plus confirmatory imaging: the diagnosis is suggested clinically by the combination below and established by vessel imaging.
- Differential diagnosis
Vertebral artery dissection: occipital or posterior neck pain with posterior-circulation symptoms (dysarthria, dysphagia, ataxia, vertigo, hemifield visual loss) rather than anterior-circulation…
- Diagnosis
Established by vessel imaging showing an intramural hematoma: the diagnosis is confirmed by direct visualization of the dissected segment, most often as a crescent-shaped, hyperintense intramural…
- Management
Initial step: in a patient presenting with acute ischemic stroke from dissection who meets standard eligibility criteria, intravenous thrombolysis is not contraindicated by dissection alone and…
- Complications
Ischemic stroke: the principal early complication, from artery-to-artery embolism off the dissected, thrombogenic segment.
- Prognosis
Generally favorable: most dissected carotid arteries heal over weeks to months with resolution or improvement of the intramural hematoma and lumen on follow-up imaging.
- Prevention
No established primary prevention exists for spontaneous dissection, since most cases are unpredictable tears without a modifiable precipitant.
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Related articles
- Vertebral artery dissection
A tear in the vertebral artery wall, spontaneous or from neck trauma or manipulation, that causes posterior circulation ischemia through thrombus formation or direct luminal narrowing. Presents with posterior neck or occipital headache plus brainstem or cerebellar signs, most classically a lateral medullary (Wallenberg) syndrome; diagnosed with MRI/MRA or CT angiography of the neck and treated with antithrombotic therapy.
- Cerebellar stroke
Cerebellar stroke, ischemic or hemorrhagic infarction of the cerebellum, presents with vertigo, truncal ataxia, dysarthria, and limb incoordination and is diagnosed with brain MRI when CT is falsely reassuring. Its defining danger is delayed swelling that compresses the brainstem and fourth ventricle, which is treated with emergent decompressive suboccipital craniectomy.
- Carotid artery stenosis
Carotid artery stenosis is atherosclerotic narrowing of the extracranial internal carotid artery that raises ischemic stroke risk, graded by percent luminal narrowing on duplex ultrasound. Symptomatic stenosis of at least 50% warrants urgent revascularization; asymptomatic stenosis under 80% is managed with best medical therapy alone, including a high-intensity statin and antiplatelet agent.
- Basilar artery occlusion
Basilar artery occlusion is a posterior circulation large-vessel stroke that threatens the brainstem, cerebellum, and thalami, presenting with rapidly progressive quadriparesis, cranial nerve palsies, and impaired consciousness, up to locked-in syndrome or coma. Diagnosis requires urgent CT angiography, and management is emergent reperfusion with IV alteplase followed by mechanical thrombectomy in eligible patients.