Under recognized yet a clinically relevant impact of aneurysm location in Distal Anterior Cerebral Artery (DACA) aneurysms: insights from a contemporary surgical experience.

Aneurysms of the distal anterior cerebral artery (DACA) are rare but surgically challenging. Despite a known therapeutic implication of the aneurysm location on the DACA territory, the literature is unclear about its clinical and prognostic significance. Our surgical experience over the last 5 years was reviewed to compare the clinical, operative, and outcome characteristics between aneurysms located below the mid portion of the genu of the corpus callosum (called proximal aneurysms) to those distal to this point (called distal aneurysms). A prognostic factor analysis was done using uni and multivariable analysis. A total of 34 patients were treated (M: F = 1:2.3). The distal group had a higher frequency of poor clinical grade at presentation (n = 9, 47.4%) in contrast to (n = 2, 13.3%) proximal aneurysms (p = 0.039). Despite an overall tendency for a delayed functional improvement in these patients, the results were mainly due to favorable outcomes in the proximal group (favourable functional outcomes at discharge and at last follow-up being 80% and 86.7% respectively). On the multivariable analysis, only WFNS grade (> 2) at presentation (OR = 13.75; 95CI = 1.2-157.7) (p = 0.035) and application of temporary clips (AOR = 34.32; 95CI = 2.59-454.1) (p = 0.007), both of which were more in the distal group, independently predicted a poor long term functional outcome. Thus, the aneurysm location impacts the preoperative clinical grade, the intraoperative aneurysm rupture risk rate as well as the temporary clipping requirement. A combination of these factors leads to worse short and long-term functional outcomes in the distal DACA aneurysms.