Thromboembolic Events Detected by Diffusion-Weighted Magnetic Resonance Imaging after Flow Diverter Treatment: The Impact of Procedure Time

Abstract

Periprocedural thromboembolism is a serious complication of endovascular treatment for intracranial aneurysms. In addition to symptomatic ischemia, asymptomatic postprocedural diffusion-weighted image-positive lesions (DPLs) are considered important. However, few studies have reported significant risk factors associated with DPLs and symptomatic ischemic stroke after flow diverter (FD) treatment. This study aimed to investigate the frequency and risk factors associated with DPLs after FD treatment. Between November 2015 and December 2021, 84 patients harboring 85 untreated, unruptured intracranial aneurysms treated with FD were enrolled. DPLs after FD treatment were confirmed in 74 patients (87.1%), among whom 69 (93.2%) were clinically asymptomatic. In the univariate analyses, age >55years (P= 0.040), smoking (P= 0.023), preprocedural P2Y12 reaction unit value of >185 (P= 0.030), larger dome size of >9.3mm (P= 0.013), and prolonged procedure time >80minutes (P < 0.001) were significantly associated with postprocedural DPLs. In the multiple logistic regression model, only prolonged procedure time >80minutes (oddsratio, 10.72; 95% confidence interval, 1.346-233.899; P= 0.023) was statistically significant. The mediator effect showed that the association between procedure time and the occurrence of DPLs was not significantly modified by any other factors, although only adjunctive coiling showed a tendency (P-value for interaction= 0.070). Prolonged procedure time >80minutes was the only identifiable factor related to postprocedural DPLs. Adjunctive coiling tended to mediate the effects of a prolonged procedure time on the occurrence of DPLs after FD treatment.