Drill turn technique for enhanced visualization of wide-neck bifurcation aneurysms in Y-stent-assisted coiling with LVIS EVO stents: technical considerations and mid-term results

Crossing Y-stent-assisted coiling (CYSAC) is a feasible yet technically challenging technique for the treatment of wide-neck bifurcation aneurysms (WNBAs).

To present mid-term results of Y-stent-assisted coiling (YSAC) using the LVIS EVO stent and to describe our “drill turn” technique for stent crossing.

This retrospective, observational study included 37 consecutive patients treated with YSAC using LVIS EVO stents at five centres between September 2020 and March 2023.

Immediately after treatment, 31 of the 37 patients (83.8%) achieved Raymond–Roy occlusion classification (RROC) Class I occlusion, while 5 patients (13.5%) had Class II and 1 patient (2.7%) had Class III occlusion. The mean follow-up period was 32.8 months (range: 11–41 months), and all patients underwent follow-up imaging after ≥ 6 months. On follow-up imaging, 34 patients (92%), including all those with immediate RROC Class I occlusion, 2 with Class II, and 1 with Class III, showed Class I occlusion. One patient with RROC Class II occlusion demonstrated a gradual decrease in residual filling, while one large partially thrombosed middle cerebral artery aneurysm and one large basilar tip aneurysm (8%) with residual neck filling remained unchanged on the 6-month digital subtraction angiograph.

Utilizing the described drill turn technique, CYSAC with LVIS EVO stents was found to be feasible and safe for WNBA treatment, with high and stable occlusion rates observed during mid-term follow-up.