LAUSR

BACKGROUND Nearly 20% of individuals with an aneurysm will harbor multiple aneurysms-these individuals are at increased risk of subarachnoid hemorrhage. Treatment of bilateral aneurysms with flow diverters (FD), Pipeline Embolization Device (PED) has not yet been established as an effective therapy. Our aim is to evaluate the safety and efficacy of a two-stage treatment of bilateral aneurysms with PEDs placed 6 months apart. METHODS This study is a retrospective review analyzing the clinical and angiographic outcomes of 16 individuals with bilateral aneurysms who were treated with a two-stage flow diversion treatment at a tertiary referral center between January 2010 and July 2018. RESULTS 16 individuals with 33 aneurysms who were treated with flow diversion bilaterally; one patient had two aneurysms treated with a single FD on the contralateral side. The aneurysms treated were either ophthalmic, superior hypophyseal, posterior communicating, or cavernous segment aneurysms with an average size of 6.5 mm. There were no major complications such as in-stent stenosis, thromboembolic events, distal intra-parenchymal hemorrhage, re-rupture, stent migration, or neurological death. All patients had good functional outcomes. At 24 months follow-up, 81% of aneurysms showed complete occlusion of all treated aneurysms. No aneurysm required re-treatment. CONCLUSIONS This study demonstrates that a two-stage flow diversion treatment of bilateral aneurysms is both safe and efficacious. Timing of the contralateral flow diverter stent is critical. We found that 6 months allows for adequate neurological recovery and stent endothelization.