Factors determining the best surgical exposure and safe clip positioning in surgical treatment of anterior communicating artery (AComA) aneurysms - particular significance of AComA complex rotation in the axial plane.

Abstract

The aim of this study was to evaluate whether Anterior Communicating Artery (AComA) complex rotation in axial plane may influence the ease of surgical exploration in this region and safety of clip positioning when left vs right-sided approach is compared. This is a retrospective study based on analysis of patients operated due to AComA aneurysm, both ruptured and unruptured. AComA complex position in relation to coronal plane was evaluated using 3D-CTA VR reconstructions. Next, comparison between surgical approach from the side where A1-A2 junction (angle) was located anterior and posterior to coronal plane was performed in relation to surgical difficulties and intra- and postoperative complications. Subgroup statistical analysis revealed that there is a strong and statistically significant correlation between AComA complex rotation and surgical difficulties expressed by the need of repeated temporary clip application and brain transgression. When anterior vs posterior angle side approach was compared in relation to surgical difficulties and complications, there was a statistically significant difference with strong correlation (p < 0.05) in favour of posterior angle side approach. Interestingly, in 72.7% and 45.5% of patients that were operated from the side where A1-A2 junction was located posterior to coronal plane, the approach was performed form the side of a non-dominant A1 and aneurysm dome projection side, respectively. Despite its limitations, our results suggest that microsurgical clipping strategy of AComA aneurysms should at least include AComA complex rotation in axial plane, besides well acknowledged factors, when deciding from which side these lesions will be approached.