Introduction: We conducted a systematic review of the literature to evaluate the safety and efficacy of treatment strategies for PICA aneurysms.
Methods: A systematic search of Medline, EMBASE, Scopus, and Web of Science was done for studies published through November 2015. We included studies that described treatment of PICA aneurysms with ≥10 patients. Random-effects meta-analysis was used to pool the following outcomes: complete occlusion, technical success, periprocedural morbidity/mortality, stroke rates, aneurysm recurrence/rebleed, CN palsies rates, and long-term neurological morbidity/mortality.
Results: We included 29 studies with 796 PICA aneurysms. When considering all ruptured PICA aneurysms, complete occlusion rates were 97.1 % (95 % CI = 94.5-99.0 %) in the surgical group and 84.3 % (95 % CI = 73.8-92.6 %) in the endovascular group. Aneurysm recurrence occurred in 1.4 % (95 % CI = 0.3-3.3 %) after surgery and in 6.9 % (95 % CI = 3.6-10.9 %) after endovascular treatment. Overall neurological morbidity and mortality were 14.4 % (95 % CI = 8.7-21.2 %) and 9.8 % (95 % CI = 5.8-14.8 %) after surgery and 15.1 % (95 % CI = 10.5-20.2 %) and 17.1 % (95 % CI = 11.5-23.7 %) after endovascular treatment, respectively. When considering all unruptured PICA aneurysms, complete occlusion rates were 92.9 % (95 % CI = 79.5-100 %) in the surgical group and 75.7 % (95 % CI = 45.4-97.1 %) in the endovascular group. Overall long-term good neurological outcome rates were 91.5 % (95 % CI = 74.4-100 %) in the surgical series and 93.3 % (95 % CI = 82.7-99.5 %) in the endovascular group.
Conclusions: Our meta-analysis demonstrated that both treatment modalities are technically feasible with high rates of technical success and effective with sufficient long-term aneurysm occlusion rates. Our data suggest that surgery is associated with superior angiographic outcomes. While endovascular therapy could be a reasonable first-line treatment option for proximal PICA aneurysms, surgery remains a highly effective first-line choice for distal PICA aneurysms. These findings should be considered when deciding the best therapeutic strategy.
Keywords: Aneurysm; Endovascular treatment; Meta-analysis; Microsurgery; PICA.