Stent-assistant versus non-stent-assistant coiling for ruptured and unruptured intracranial aneurysms: A meta-analysis and systematic review

Background: Several different endovascular and non-invasive treatment methods are suggested for the various types of intracranial aneurysms including simple, balloon-assisted, and stent-assisted coiling (SAC). Previous studies investigated the safety and efficacy of SAC versus non-stent-assisted coiling (non-SAC) but the results were controversial. We aim to perform a systematic review and meta-analysis to compare the efficacy and safety of SAC with non-SAC technique in stratifying by the ruptured and unruptured aneurysms. Methods: PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials were searched in April 2022 for studies investigated the efficacy and safety of SAC versus non-SAC. Results: Overall, 26 studies entered into our qualitative and quantitative synthesis. We found that there was overall lower recurrence rate in SAC versus non-SAC significant (RR: 0.43, 95%CI: 0.33, 0.53). Furthermore, the comparisons were significant in unruptured (RR: 0.63, 95%CI: 0.40, 0.86), ruptured (RR: 0.29, 95%CI), and combination aneurysms (RR: 0.42, 95%CI: 0.30, 0.54). Also, we found higher risk of intraprocedural rupture for SAC versus non-SAC in unruptured aneurysms (RR: 1.40, 95%CI: 1.31, 1.50). Investigating hemorrhagic events risk showed that there was significant difference in ruptured (RR: 1.73, 95%CI: 1.12, 2.34) and combination aneurysms (RR: 0.60, 95%CI: 0.37, 0.82). There was no significant difference in immediate occlusion rate, complete occlusion, and risk of ischemic events in our analysis. Conclusion: Overall, our findings demonstrated that SAC may have higher efficacy in term of recurrence rate, but also may have a higher risk of complications in the treatment of intracranial aneurysms. As there are several factors affecting the outcomes and safety of these interventions, further RCTs controlled for multiple factors are required better guide the neurointerventionists choose the best strategy.