Abstract WP91: Open-cell Stent Design for Coil Embolization of Side Branching Vessel Internal Carotid Artery Aneurysms: Clinical and Angiographic Results

Abstract

Background and Purpose: Treatment of side branch internal carotid artery (ICA) cerebral aneurysms, i.e. ophthalmic and anterior choroidal artery aneurysms, pose unique treatment difficulties. Visual loss or anterior choroidal artery territory infarcts have been reported as clinical sequelae for both surgical and endovascular treatment approaches for these aneurysms. Here we evaluate the safety and efficacy of endovascular treatment by use of open cell design for stent assisted coil embolization of side branch ICA aneurysms. Materials and Methods: Between 2007 and 2012, 60 consecutive patients treated with open cell stent assisted coil embolization for a cerebral aneurysm were reviewed. Inclusion criteria were wide neck aneurysms incorporating an ICA branching vessel at the neck of the aneurysm. Aneurysm occlusion was assessed on cerebral angiograms by using the Raymond Score immediately after endovascular treatment and at 6 months follow-up. Clinical outcomes were assessed by the modified Rankin Scale (mRS) at baseline, discharge and 6 months follow-up. Results: Of the 60 consecutive patients treated with open cell stent assisted coil embolization, 6 patients were identified as having side branching ICA cerebral aneurysms. In each of these 6 cases, the side branching ICA vessel originated from the neck of the aneurysm. Flat panel CTA obtained post open cell stent deployment showed preferential outward herniation of open cell stent struts towards the neck of the aneurysm, thus protecting the side branching vessel. On immediate post treatment angiograms, a Raymond Score of 1 was assessed on each of these 6 aneurysms with patency of the side branching vessel. A mRS of 0 or 1 was assessed at baseline and at discharge on all 6 patients. A Raymond Score of 1 was also identified on 3 of the 6 aneurysms on the 6 months follow-up exam. 3 additional patients are still awaiting their 6 months follow-up. Of the 3 patients that have received 6 months follow-up, all 3 patients have a stable mRS of 0 or 1. Conclusions: Our short to mid-term results for open cell stent assisted coil embolization of side branch ICA aneurysms is safe and effective. The independent open cell stent strut’s outward radial force protects side branching vessels that originate from the neck of these aneurysms.