Treatment outcome of flow-diversion with Surpass Evolve stent for unruptured intracranial aneurysms: Predictors of poor occlusion

We aimed to investigate the predictors of aneurysm occlusion following flow diversion treatment for unruptured intracranial aneurysms (UIA) using the Surpass Evolve (SE) stent. The radiological and clinical outcomes of UIAs treated using SE stent at a single tertiary hospital were reviewed retrospectively. We categorized radiological outcome into the poor (O'Kelly-Marotta [OKM] grade A-B) and favorable occlusion group (OKM grade C-D). Univariate and multivariate analyses were conducted to identify risk factors associated with poor occlusion. A total of 68 unruptured intracranial aneurysms in 52 patients were treated in our institution from December 2019 to July 2024. At last radiological follow-up (mean 17.5±10.1 months), the overall favorable occlusion rate was 79.4% (n=52). Multivariate analysis showed larger aneurysm (p=0.011, OR=0.89, 95% CI [0.81-0.98]) and presence of incorporated branch (p=0.007, OR=8.26, 95% CI [1.78-38.28]) were associated with independent factors for poor occlusion, respectively. Procedural mortality and morbidity were 0% (n=0) and 1.9% (n=1). One patient presented with delayed ischemic stroke (1.9%, n=1) without permanent neurological deficit. Treatment for UIAs using the Surpass Evolve flow-diverting stent might be feasible for efficacy and safety. In this study, larger size of aneurysm and branch incorporated aneurysm were associated with poor occlusion after flow-diversion using SE stent.