Occlusion rates of intracranial aneurysms treated with the Pipeline embolization device: the role of branches arising from the sac.

OBJECTIVEThe aim of this study was to compare the clinical and angiographic outcomes of intracranial aneurysms with and without branches arising from the sac after Pipeline embolization device (PED) treatment.METHODSThis retrospective 2-center comparative study included 116 patients with 157 aneurysms that were treated with PEDs. Aneurysms were divided into 2 groups: one group had branches arising from the sac and the other group did not. Study end points included total aneurysm occlusion assessed by angiography at 6 and 12 months, death or stroke, technical complications, in-stent stenosis, patency of covered branches, and transient ischemia.RESULTSOne hundred fifty-one aneurysms (96%) were located in the internal carotid artery. A branch arising from the sac was observed in 26 aneurysms. Complete occlusion was found in 120 of 156 aneurysms at 6 months (76.92% [95% CI 69.71%-82.84%]) and in 136 of 155 aneurysms at 12 months (87.74% [95% CI 81.28%-92.27%]). Total occlusion was more frequently observed in the group without a branch arising from the sac (84% vs 40% at 6 months, p < 0.001; 93.10% vs 60% at 1 year, p < 0.001). There were 4 (3.45% [95% CI 1.11%-9.12%]) cases of death or major stroke. Amaurosis fugax occurred in 3 patients. One patient experienced worsening of mass effect after treatment. No occlusion of branches arising from the aneurysm was observed. In-stent stenosis greater than 50% was observed in 1 case.CONCLUSIONSAneurysms treated with PEDs are less likely to be totally occluded if they have a branch arising from the sac than are aneurysms without these branches.