Risk factors for recurrence of distal anterior cerebral artery aneurysms after endovascular treatment

Objective We aimed to investigate risk factors for the recurrence of distal anterior cerebral artery (DACA) aneurysms after endovascular treatment (EVT). Methods The clinical and radiological outcomes of DACA aneurysms treated with endovascular methods at a single tertiary hospital from September 2008 to December 2021 were retrospectively reviewed. We measured the angle between two distal branches of DACA aneurysms and categorized the angle as follows: 1) Wide-angle (≥ 180 degrees), and 2) Narrow-angle type configuration (< 180 degrees). Univariate and multivariate analyses were performed to demonstrate the relationships between characteristics of DACA aneurysm and recurrence risk. Results A total of 132 DACA aneurysms were treated in our institution. Among these, 47 DACA aneurysms after EVT were included in this study. Forty patients underwent coil embolization without stent, seven for stent-assisted coil embolization. At the last follow-up (mean 30.2 ± 24.2 months), overall recurrence rate was 23.4% (n=11). Recurrence rate of the wide-angle type (9 of 23, 39.1%) was significantly higher than narrow-angle type (2 of 24, 8.3%) (p=0.041, OR=8.174, 95% confidence interval [CI] 1.094-61.066). Irregular shape of the DACA aneurysm also showed significantly higher recurrence rate (p=0.011, OR=10.663, 95% CI 1.701-66.838) after endovascular treatment. Conclusion The wide-angle between two distal branches of DACA aneurysm and irregular shape might be independent risk factors for the recurrence after endovascular treatment for DACA aneurysms.