Multiple overlapping stents as monotherapy in the treatment of 'blister' pseudoaneurysms arising from the supraclinoid internal carotid artery: a single institution series and review of the literature.

Abstract

The 'blister-type' aneurysm is one of the most devastating cerebrovascular lesions. Flow diversion with stent reconstruction is an emerging treatment and has shown promising initial results. To evaluate the experience of one institution using stent reconstruction for pseudoaneurysms of the supraclinoid internal carotid artery and to compare with a review of the literature. A retrospective review from one institution identified eight patients with 'blister' aneurysms over a 47-month period. The Raymond scale was used to classify the aneurysms. Clinical data were obtained using the modified Rankin Scale (mRS) and the National Institute of Health Stroke Scale. A literature review was performed and compared with our results. Clinical and angiographic data were obtained. After treatment, two aneurysms were Raymond class 1 (25%) and six were class 3 (75%). Of the class 3 aneurysms, two required retreatment, three (50%) progressed to complete occlusion and three (50%) had persistent aneurysm filling. Clinical data revealed two patients with mRS score of 0 (25%), five with mRS score of 1 (62.5%) and one with mRS score of 2 (12.5%). From the literature review, residual filling was evident in nine patients (64.3%) and complete occlusion in four (28.6%). On follow-up angiography, nine (64.3%) were occluded, two (14.3%) had residual neck filling and one (7.1%) had persistent aneurysm filling. Thirteen patients (92.9%) had an mRS score of 2 or better. Combining the available experience, patients demonstrated either improvement (n=9, 41%) or stability (n=11, 50%). Only two (9%) had progression requiring retreatment. Endovascular stent remodeling of 'blister-type' aneurysms is a safe and effective strategy.