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

Department of Neurology, Tao-Yuan General Hospital, Tao-Yuan City, Taiwan, ROC.
European Neurology (Impact Factor: 1.5). 02/2007; 57(4):208-11. DOI: 10.1159/000099160
Source: PubMed

ABSTRACT Anterior cerebral artery A1 segment hypoplasia is an uncommon fetal variant of the circle of Willis. The frequency of this congenital variation is 1-13% as derived from angiograms and autopsy reports. Impaired collateral blood flow through the circle of Willis is a recognized risk factor for ischemic stroke. The A1 segment of the anterior cerebral artery is a principal supplier of anterior collateral blood flow. The aim of our study was to determine whether A1 segment hypoplasia may be responsible for acute ischemic stroke. We consecutively examined 280 acute ischemic stroke patients (aged 66.9 +/- 14.2 years). Cerebral magnetic resonance angiography was performed within 72 h of ischemic stroke onset. The overall incidence of A1 variation in our experimental group was 15.0% (n = 42, agenesis/hypoplasia = 18/24), which was statistically higher than in the control group (n = 12). The majority (n = 30, 71.42%) had ipsilateral striatal lacunar infarctions. Based on our results, A1 agenesis/hypoplasia appears to be a risk factor contributing to ischemic stroke, especially to strokes in arteries penetrating the striatal area.

1 Bookmark
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Anomalies of the branches of internal carotid artery can lead to serious clinical conditions like stroke. Wereport here an anomalous pattern of the cerebral arteries. The left internal carotid artery was smaller than theright and it continued as middle cerebral artery instead of dividing into anterior and middle cerebral arteries.It also failed to give the posterior communicating artery. The right internal carotid artery was almost doublethe size compared to the left internal carotid artery. It gave rise to a common trunk which divided into rightand left anterior cerebral arteries. The knowledge of these anomalous arteries may be useful for neurosurgeons,radiologists and clinicians in general.
    Neuroanatomy. 01/2008;
  • Source
    Circulation 07/2011; 124(3):360-2. · 15.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Despite research in the anatomical sciences for the last 200 years, some structures of the human body remain controversial or incompletely described. One of these structures is the A1 segment of the anterior cerebral artery (ACA). To analyze the A1 segment of the ACA using novel stereoscopic methods because the 3-dimensional morphometry of the ACA is important to neurosurgeons. A digital-image computer-based system was used to analyze the A1 segment of 230 ACAs derived from computed tomography. Data analysis included the inner diameter, length, and volume and calculation of A1 symmetry, hypoplasia, and deviation, and tortuosity indexes. Hypoplasia of the A1 segment was found in 0.87% and only on the right sides, whereas asymmetry was found in 42.6% and was more common in female patients. Right A1 segments tended to be longer in male patients, and this reached significance. Also of significance was the correlation of an increased length with age. Right A1 segments tended to have greater volumes, and this was significant in a comparison of male and female patients. Tortuosity indexes tended to be greater for left sides, but deviation indexes tended to be greater on the right sides. Morphometric data of the A1 segment of the ACA as analyzed in the present study may be of utility to the neurosurgeon. Right A1 segments tend to be more tortuous, more deviated, longer, and narrower than left A1 segments.
    Neurosurgery 12/2010; 67(6):1768-82; discussion 1782. · 2.53 Impact Factor

Full-text (2 Sources)

Available from
Jun 3, 2014