Safety, Efficacy, and Durability of Stent-Assisted Coiling Treatment of M2 (Insular) Segment MCA Aneurysms.

Background and Purpose: Most distal MCA aneurysms are located within the insular segment, which lies between the limen insulae and circular sulcus. However, experience is limited in the microsurgical and endovascular management of insular segment MCA aneurysms. In this multicenter retrospective case series, we aimed to investigate the safety, efficacy, and durability of stent-assisted coiling for treatment of insular segment MCA aneurysms.
Materials and Methods: A retrospective review was performed to identify patients with insular MCA aneurysms that were treated with stent-assisted coiling. The technical success of the procedures and the initial and follow-up clinical and angiographic outcomes were assessed. Periprocedural and delayed complications were reviewed.
Results: Twenty-seven aneurysms in 27 patients with a mean age of 53.3 (SD,11.3) years were included. The mean size of the aneurysms was 6.3 (SD 2.6) mm. Endovascular procedures were successfully performed in all patients. Immediate postprocedural angiography revealed complete aneurysm occlusions in 81.5%. Periprocedural complications developed in 7.4% without causing permanent morbidity. A delayed thromboembolic complication resulted in a minor permanent morbidity in 1 patient (3.7%). There was no mortality. The mean duration of angiographic follow-up was 19.5 (SD, 9.8)  months. The last follow-up examinations showed complete occlusion in 92.6%. During the follow-up period, none of the treated aneurysms showed recanalization.
Conclusions: The results of this study demonstrate that stent-assisted coiling with a low-profile self-expandable stent is a feasible and relatively safe technique for endovascular treatment of insular segment complex MCA aneurysms. Additionally, it provides an effective and durable treatment for insular MCA aneurysms.
(© 2022 by American Journal of Neuroradiology.)