Use of Pipeline Embolization Device for Posterior Circulation Aneurysms: Single-Center Experiences with Comparison with Anterior Circulation Aneurysms

Objective: To evaluate the performance of the Pipeline embolization device (PED) for posterior circulation aneurysms.

Methods: From November 2015 to November 2016, 35 patients with 38 posterior circulation aneurysms were treated with the PED in this retrospective study. We evaluated the angiographic and clinical outcomes of these aneurysms at last follow-up, and made a comparison between anterior (n = 163) and posterior circulation (n = 38) aneurysms regarding the technical nuances, occlusion rate, complications rate, and time to occlusion to explore whether we should rationalize the use of the PED for these aneurysms.

Results: With a median follow-up time of 5.5 months, complete occlusion was achieved in 33 aneurysms (91.7%). Aneurysms with stenosis parent artery tended to have lower occlusion rate (P = 0.064; odds ratio, 0.074; 90% confidence interval, 0.001-1.781), and V4 segment aneurysms tended to occlude themselves much faster than vertebrobasilar junction aneurysms (median, 148 vs. 246 days, respectively; P = 0.076). The periprocedural complication rate was 10.8%, and no major adverse events occurred. Compared with anterior circulation aneurysms, shorter procedure time (116.0 vs. 135.4 minutes, P = 0.012) and higher occlusion rate (91.4% vs. 72.8%, P = 0.023) were achieved for posterior circulation aneurysms. Besides, technical event rate (8.1% vs. 14.1%, P = 0.424) and complication rate (10.8% vs. 18.4%, P = 0.338) tended to be lower. Survival analysis indicated a shorter interval to complete occlusion for V4 segment aneurysms compared with anterior circulation (148 vs. 191 days, respectively; P = 0.047).

Conclusions: PED has a favorable performance at posterior circulation, and it is rational to expand the indication to include these aneurysms. However, a case-control study is still needed to further expatiate whether the PED has advantages over traditional endovascular treatment.