Case Series, Systematic Review, and Meta-Analysis of Basilar Bifurcation Aneurysms Treated Between 2001 and 2017

INTRODUCTION: A lower rate of aneurysmal recanalization in stent assisted coiling vs coiling alone has been observed. This study aims to stratify and compare degree of occlusion outcomes by treatment modalities for basilar bifurcation aneurysms. Secondarily, this study aims to stratify and compare postoperative adverse events. METHODS: Medical literature including MEDLINE and EMBASE database was searched. We performed metaregressions, bias analysis, and fail-safe N. We controlled for the quality of the studies. RESULTS: Eligible studies (N = 12) and study center patients (n = 117) data were pooled for a total of 396 nonduplicated patients. Patients were separated into 4 groups: microsurgical, stent-assisted coiling, coiling, stent only. Stent-assisted coiling had a lower rate of retreatment (17% vs 24%) and higher rate of post-treatment haemorrhage (5% vs 3%) compared to coiling. Stent-assisted coiling had a higher rate of complete occlusion (55% vs 45%) and lower rate of residual aneurysm (15% vs 23%) compared to coiling. Comparative analyses were performed. Microsurgical technique remained the most morbid treatment modality with the best rate of complete occlusion (93%) and lowest rehemorrhage (2%) and retreatment rate (5%). CONCLUSION: This is the first and largest meta-analysis focusing on patients treated for basilar bifurcation aneurysm. This is the first study to stratify and compare degree of occlusion and clinical outcomes per treatment modality. This is the first study to report higher rates of post-treatment hemorrhage with stent-assisted coiling. This study provides benchmark data to guide clinicians in future treatment decision-making and encourages future research to stratify outcomes.