Symptomatic ischemic complications following endovascular treatment of vertebral artery dissecting aneurysms

Purpose The aim of this study is to investigate the clinical and radiological features related to the symptomatic ischemic complications of vertebral artery dissecting aneurysm (VADA) following endovascular treatment (EVT). Methods The clinical and radiological features of 127 VADAs, which were treated in a single tertiary institute between September 2008 and December 2020, were retrospectively reviewed. We defined a thrombosed aneurysm as being one which the thrombus was in the aneurysm in magnetic resonance imaging (MRI). Symptomatic ischemic complication was defined as a case in which acute infarction was confirmed on diffusion weighted image after EVT with associated clinical symptoms. Univariate and multivariate analyses were executed to demonstrate the associations between symptomatic ischemic complication and characteristics of VADA. Results The rate of symptomatic ischemic complication was 13.4% (17 of 127). The thrombosed aneurysms were observed in 24.4% (31 of 127) and posterior inferior cerebellar artery (PICA) involvement was shown in 38.6% (49 of 127). Multivariate logistic regression analysis demonstrated that thrombosed aneurysms (odds ratio [OR] = 8.54, 95% confidence interval [CI] 1.98-36.87, p = 0.004) and PICA involvement (OR = 4.26, 95% CI 1.03-17.68, p = 0.046) were significantly associated with symptomatic ischemic complications following EVT. Conclusion This study showed that the VADAs with intra-aneurysmal thrombose and PICA involvement may be independent risk factors for symptomatic ischemic complications following EVT. Therefore, when the thrombosed VADAs with PICA involvement are observed, practitioners may consider close postoperative monitoring for early detection of ischemic complications.