Interdisciplinary Neurosurgery (Mar 2022)
A rare case of azygous ACA with bilateral ICA aneurysm and distal ACA aneurysm
Abstract
Azygous ACA is one of the rare anatomic variants of the anterior cerebral artery. Predisposition to aneurysm development is attributed to the alteration in flow dynamics. This is most commonly seen in the anterior circulation, causing distal ACA aneurysm to be the most commonly associated vascular pathology. Although neurosurgical literature is replete with such cases, there have been no case reports where bilateral ICA aneurysms are also present with the distal ACA aneurysm. In this case, the presence of the hypoplastic left A1 segment might have predisposed the other segments of the Circle of Willis to hemodynamic stress. Thus, whenever we come across an azygous ACA in association with an additional anomaly we should be vigilant enough to look for other pathologies beyond the commonly encountered distal ACA aneurysm. On the other hand, we should always search for a DACA aneurysm, when we come across an azygous ACA despite having an aneurysm at other sites. The presence of azygous ACA also poses a technical challenge due to the risk of ischemic insult to anterior regions of bilateral hemispheres during temporary clipping of the single A2 trunk. So, the presence of multiple anatomic anomalies not just increases the number of vascular pathologies but also enhances the challenges that the surgeon has to face while planning the strategic approach to tackle all the lesions.
