Prevalence of Variations in the Anterior Communicating Artery Complex of the Circle of Willis: A CT Angiography Study in Malaysia

Abstract

INTRODUCTION: The anterior communicating artery complex (ACoA complex) within the circle of Willis, contributing to communicating arterial supply to the brain, exhibits significant anatomical diversity. Given the vulnerability of brain tissues to cell death resulting from poor blood supply, knowledge on this variability becomes crucial for diagnosing and managing diseases affecting the arterial supply to the brain. MATERIALS AND METHODS: A cross-sectional study was conducted to determine the prevalence and to give a description of these variations based on reconstructed CT angiographic (CTA) images. We included all individuals who underwent head CT angiography at a hospital in Kuantan, Pahang, Malaysia for various reasons between January 2009 and August 2015. A total of 81 CT angiographic images were analyzed for different variations, encompassing hypoplasia, aplasia, and duplication of the anterior communicating artery, as well as hypoplasia and aplasia of the A1 and A2 segments of the anterior cerebral artery, the A2 segments arising from a common trunk, and the third A2 segment. RESULTS: Ten distinct variation types were identified, with the typical pattern observed in 35.8% of cases. Vascular variations accounted for 64.2%, signifying a higher prevalence compared to previous studies. The cases presenting variations in the anterior communicating artery constituted 43.2%, with the aplasia being the most prevalent anatomical variation at 28.4%. CONCLUSION: The study highlights a higher prevalence of anatomical variations in the ACoA complex than the typical pattern.