Azygos anterior cerebral artery
Citation, DOI, disclosures and article data
At the time the article was created Frank Gaillard had no recorded disclosures.View Frank Gaillard's current disclosures
An azygos anterior cerebral artery (sometimes spelled azygous) is a rare variant of the circle of Willis where the two A1 segments of the anterior cerebral artery (ACA) join to form a single trunk. As a result, there is no anterior communicating artery. This organization is similar to that seen in lower primates 2.
They are present in approximately 0.4-1% of the population 1.
An azygos anterior cerebral artery is associated with numerous abnormalities, including 1:
Berry aneurysms are often seen at the eventual bifurcation of the single vessel, due to either altered hemodynamics, a congenitally abnormal wall, or both. The reported incidence varies widely at 13-71% 1.
As there is frequent hypoplasia of the anterior communicating artery and supply of the medial surface of the hemispheres by contralateral anterior cerebral artery branches, confirmation of an azygos anterior cerebral artery can be difficult on angiography 2. Cross compression views can be helpful.
- 1. Huh JS, Park SK, Shin JJ et-al. Saccular aneurysm of the azygos anterior cerebral artery: three case reports. 2007;42 (4): 342-5. doi:10.3340/jkns.2007.42.4.342 - Free text at pubmed - Pubmed citation
- 2. LeMay M, Gooding CA. The clinical significance of the azygos anterior cerebral artery (A.C.A.). Am J Roentgenol Radium Ther Nucl Med. 1966;98 (3): 602-10. Am J Roentgenol Radium Ther Nucl Med (abstract) - Pubmed citation
- 3. Rossi A. Pediatric neuroradiology. Springer Verlag. (2005) ISBN:3540410775. Read it at Google Books - Find it at Amazon