Variants of cerebral arteries – anterior circulation

Abstract

SummaryAdvances in imaging techniques allow for in vivo identification of abnormalities and normal variants of cerebral arteries. These arterial variations can be asymptomatic and uncomplicated although, some of them increase the risk of aneurysm formation, acute intracranial hemorrhage, play a vital role in neurosurgical planning or can be misidentified as serious pathology and medical errors. The goal of this publication is to discuss arterial anomalies of anterior cerebral circulation, their prevalence and demonstrate radiological images of some of those variants. In this article we will discuss variants of internal carotid artery, anterior cerebral artery, anterior communicating artery, middle cerebral artery, persistent stapedial artery and fenestration.

Thrombosis of the Azygos Anterior Cerebral Artery

“…The AACA is a rare variant, characterized by the absence of the anterior communicating artery and the union of the two proximal segments (A1) of the anterior cerebral arteries, forming a single stem (A2) and ascending through the interhemispheric fissure [1–3]. The occurrence of occlusion of this vessel determines bifrontal infarctions, with potentially devastating functional consequences, so it is important to recognize this anatomical variation in imaging exams.…”

“…The anatomical recognition of this variant becomes important for the occurrence of saccular aneurysms, relatively common (13–71%), associated malformations (dysgenesis of the corpus callosum, lobar holoprosencephaly, septooptic dysplasia, porencephalic cysts, and arteriovenous malformations), and presence of bifrontal infarctions in case of occlusion [1]. …”

“…It is characterized by a single vessel which provides the blood supply to both anterior cerebral hemispheres. This anatomical variation has a significant impact on blood hemodynamics of the frontal lobe, especially in cases of occlusion, determining bifrontal infarction [1–3]. …”

Rupture of a giant aneurysm of the accessory middle cerebral artery: a case report and a literature review

“…По данным литературы [3], аневризмы чаще всего формируются в проксимальных отделах добавочной артерии (в устье). Имеется несколько наблюдений, где аневризма, как и в описанном нами случае, отходила дистальнее устья -от ствола добавочной артерии [5,15].…”

Acute Stroke due to Electrocution: Uncommon or Unrecognized?

“…The interesting but unfortunate finding of A1 segment aplasia contributed to significant bilateral frontal lobe injury in our patient. A1 segment aplasia is an uncommon developmental defect seen in approximately 2% of cases of stroke on angiograms [18]. Bilateral frontal lobe stroke due to A1 segment aplasia has been reported in only three case reports [19].…”