114 Treatment of Bifurcation Aneurysms Using Single Stent-Coiling With Relation to Aneurysm Configuration: A Cohort Study of Two Academic Institutions in the United States.

INTRODUCTION Stent-coiling of bifurcation aneurysms has significantly expanded the spectrum of aneurysms amenable to endovascular therapy. A variety of techniques have evolved to deal with wide-necked bifurcation aneurysms such as Y-stenting and WEB embolization device. In our 2 institutions, we have primarily used a single stent coiling to treat most bifurcation aneurysms. We present a large series in which a single stent was utilized with angiographic and clinical outcomes. METHODS Two academic institutions in the United States contributed prospectively maintained data on consecutive patients with bifurcation aneurysms treated with single stent coiling between 2007 and 2015. RESULTS A total of 58 bifurcation aneurysms were treated with single stent coiling at the 2 institutions. The aneurysms were located in the basilar bifurcation in 51.7%, carotid bifurcation in 24.1%, middle cerebral artery bifurcation in 19%, and anterior communicating artery bifurcation in 5.2%. The median aneurysm diameter, neck size, height, width, and aspect ratio were 8.4, 6, 7.5, 7.4, and 1.5 mm, respectively. Median length of follow-up was 16.5 months. Complete occlusion at last follow-up was achieved in 70.6% of cases, residual neck was found in 21.6%, and residual aneurysm was found in 7.8%. Re-treatment was needed in 12.1% of cases due to recanalization. There was a significant association between complete occlusion and smaller neck size (notably <6 mm; P = .036) and smaller width (notably <7.5 mm; P = .022). Furthermore, complete occlusion rate was lower in basilar bifurcation aneurysms (P = .088) and in large bifurcating angle (notably >180°; P = .034). Symptomatic complications occurred in 6.9% of cases. There was no mortality. CONCLUSION Treatment of bifurcation aneurysm using single stent-coiling is considered safe and effective. Complete and near-complete occlusion were achieved in 92.2% of cases. Residual aneurysm or recanalization was found only in 7.8% of cases. Therefore, the use of Y-stenting or other devices can be limited to a subset of basilar bifurcation aneurysms, with aneurysm neck wider than 7 mm and/or those with a bifurcation angle greater than 180°.