Anterior cerebral artery A1 segment hypoplasia may contribute to A1 hypoplasia syndrome

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Microsurgical Clip Obliteration of Middle Cerebral Aneurysm Using Intraoperative Flow Assessment
18:50

Microsurgical Clip Obliteration of Middle Cerebral Aneurysm Using Intraoperative Flow Assessment

Published on: September 25, 2009

Yu-Ming Chuang1, Chih-Yang Liu, Po-Jung Pan

  • 1Department of Neurology, Tao-Yuan General Hospital, Tao-Yuan City, Taiwan, ROC.

European Neurology
|February 3, 2007
PubMed

Insights

Anterior cerebral artery A1 segment hypoplasia, a variant of the circle of Willis, is linked to increased ischemic stroke risk. This finding suggests A1 agenesis/hypoplasia may contribute to strokes, particularly lacunar infarctions.

Area of Science:

  • Neurology
  • Vascular Neurology
  • Neuroimaging

Background:

  • Anterior cerebral artery A1 segment hypoplasia is a rare congenital variation of the circle of Willis.
  • Impaired collateral blood flow within the circle of Willis is a known risk factor for ischemic stroke.
  • The A1 segment is crucial for anterior collateral blood supply.

Purpose of the Study:

  • To investigate the association between A1 segment hypoplasia and acute ischemic stroke.
  • To determine if A1 segment hypoplasia is a contributing factor to ischemic stroke development.

Main Methods:

  • Consecutive examination of 280 acute ischemic stroke patients.
  • Cerebral magnetic resonance angiography performed within 72 hours of stroke onset.
  • Comparison of A1 variation incidence between stroke patients and a control group.

Main Results:

  • The incidence of A1 variation (agenesis/hypoplasia) was 15.0% in stroke patients, significantly higher than in controls.
  • A1 agenesis/hypoplasia was observed in 42 patients (18 agenesis, 24 hypoplasia).
  • Ipsilateral striatal lacunar infarctions were prevalent in 71.42% of patients with A1 variation.

Conclusions:

  • A1 agenesis/hypoplasia is a potential risk factor for acute ischemic stroke.
  • This variation may particularly contribute to ischemic strokes affecting the striatal area.
  • Findings highlight the role of circle of Willis anatomy in stroke etiology.

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