Microsurgical clipping compared to new and most advanced endovascular techniques in the treatment of unruptured middle cerebral artery aneurysms: a meta-analysis in the modern era.

Abstract Objective Analyzing occlusion, complications rate and clinical results in unruptured saccular middle cerebral artery aneurysms (MCAAs) comparing clipping to the most advance and newer endovascular techniques. Methods We conducted a literature research from January 2009 to December 2018 to evaluating the efficacy and safety of microsurgical clipping or endovascular treatment with new devices (such as Flow-diverter or WEB) in patients with unruptured MCAAs. We extracted data involved: study and intervention features, occlusion rate; time of occlusion assessment and clinical outcome. Results A total of 29 studies and 1552 patients with unruptured saccular MCAAs were included in our analysis (464 patients included in endovascular group, 1088 patients in surgical group). Overall, the rate of long-term complete/near complete occlusion was 78.1% (311/405, 95%CI=69%-87.1%,) and 95.7% (113/118, 95%CI=92%-99.3%,)after endovascular and surgical treatments, respectively (p= .001). Long-term complete occlusion rate was 60% (153/405, 95%CI=45%-74%) and 95% (112/118, 95%CI=90%-98%) after endovascular and surgical treatments, respectively (p= .001). The overall rate of treatment-related complications was 5.6% (33/464, 95%CI=3.6%-7.7%) and 2.9% (37/1088, 95%CI=0.8%-5%) among the endovascular and surgical groups, respectively (p= .001). Endovascular treatments were associated with higher rates of good neurological outcome (283/293=97%, 95%CI=95%-98%, vs 570/716=84%, 95%CI=67%-98%, p=.001). No difference was found for the mortality rate (3/464=1.5%, 95%CI=0.4%- 2.6%, vs 1/1088, 95%CI=0.1%-0.6%, p=.5). Conclusion Treatment-related complication a nd mortality are comparable among these techniques, the risk of aneurysm rupture appears very low for both strategies. Endovascular approach seems to increase the probability of good functional outcome after treatment, compared to surgery.