ISCHEMIC STROKE

Created 12/01/2022, last revision 21/04/2023

Definition

• the carotid artery web is increasingly recognized as an important cause of (recurrent) ischemic stroke in patients without other cardiovascular risk factors
• it is a thin membrane extending from the posterior wall of the carotid artery bulb into the lumen just above the bifurcation and is considered a variant of fibromuscular dysplasia  [Kim, 2019]
• various synonyms are used: carotid weblike formation, carotid pseudovalvular fold, carotid diaphragm
• a relatively rare vascular pathology with thrombogenic potential (due to blood stasis along the downstream surface of the web), which can lead to intracranial thromboembolism  [Compagne, 2019]
  • a significant risk factor for cryptogenic and recurrent ischemic stroke (the incidence rate of carotid web in cryptogenic stroke is 8.9% vs. 1.9% in the control group)   [Coutinho, 2017]

Epidemiology

• a relatively rare finding (approximately on 1-2.5% of CTAs performed)  (Coutinho, 2017)  [Compagne, 2017]
• more common in women

Clinical presentation

• often an asymptomatic, incidental lesion
• thrombus formation can lead to recurrent stroke/TIA
  • recurrence occurs in up to 29% of patients despite medical treatment [Haussen, 2019]
  • the web is a significant cause of “cryptogenic stroke” in young patients

Diagnostic evaluation

Differential diagnosis

• dissection
  • usually longer and localized distally (typically below the skull base)
  • irregular margins, sometimes with a double lumen
• atherosclerotic plaque
  • different shape, irregular margins
  • calcifications are often present

Management