Endovascular treatment of cranial aneurysms with the pipeline flow-diverting stent: preliminary mid-term results.

PURPOSE: We aimed to present our initial experience with a new self-expanding flow diverter device designed for wide-neck aneurysm treatment, assess its safety for intracranial deployment and efficacy of occlusion at mid-term follow-up.
MATERIALS AND METHODS: Forty-five consecutive patients with difficult aneurysmal anatomy underwent an endovascular treatment. Fifty-five intracranial aneurysms were clipped using the Pipeline flow-diverting stent (ev3 Inc., Plymouth, Minnesota, USA) between November 2009 and December 2011. Data including antiplatelet therapy, technical issues, complications, and imaging findings were recorded during the follow-up period.
RESULTS: Twenty-seven aneurysms were asymptomatic, 13 were symptomatic due to mass effect, seven were recurrent, six had subarachnoid hemorrhage, and two subjects presented with ischemia. There were 45 saccular, six fusiform-dissecting, and four blister aneurysms. The six-month control angiography was available in 34 subjects with an 85.3% (29/34 patients) complete occlusion rate. The overall occlusion rate according to the last angiography was 91.9% (34/37 patients). The following three major technical complications without clinical consequences were encountered: one distal wire fracture of the stent delivery system and two insufficient stent expansion. There was one fatal nonaneurysmal cerebellar hemorrhage. The overall mortality rate was 2.2% with no permanent morbidity.
CONCLUSION: The Pipeline flow-diverting stent represents an important advancement in endovascular therapy for cerebral aneurysms. Standard endovascular techniques are typically not suitable for these types of aneurysms. The device targets primary parent vessel reconstruction rather than endosaccular occlusion to achieve exclusion of the aneurysm and maintain a relatively high occlusion rate at six months.