Management of Adult Unruptured Brain Arteriovenous Malformations: An Updated Network Meta-Analysis

The management of unruptured brain arteriovenous malformations (ubAVMs) is a complex challenge to neurovascular practitioners. This meta-analysis aimed to identify the optimal management of ubAVMs comparing conservative management, embolization, radiosurgery, microsurgical resection, and multimodality. The search strategy was developed a priori according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched the Ovid Medline, Embase, Web of Science, and Cochrane Library databases to identify relevant papers. Using R version 4.1.1., a frequentist network meta-analysis was conducted to compare different management modalities for the ubAVMs. Overall, the conservative group had the lowest risk of rupture (P-score=0.77), and the lowest rate of complications was found in the conservative group (P-score=1). Among different interventions, the multimodality group had the highest rupture risk (P-score=0.34), the lowest overall complications (P-score=0.75), the best functional improvement (P-score=0.65), and the lowest overall mortality (P-score=0.8). However, multimodality treatment showed a significantly higher risk of rupture (odds ratio [OR]=2.13; 95% confidence interval [95% CI]=1.18-3.86) and overall complication rate (OR=5.56; 95% CI=3.37-9.15) compared to conservative management; nevertheless, there were no significant differences in overall mortality or functional independence when considered independently. Conservative management is associated with the lowest rupture risk and complication rate overall. A multimodal approach is the best option when considering mortality rates and functional improvement in the context of existing morbidity/symptoms. Microsurgery, embolization, and radiosurgery alone are similar to the natural history in terms of functional improvement and mortality, but have higher complication rates.