Stand-alone small low-profile braided stents for challenging unruptured posterior inferior cerebellar artery aneurysms compared to conventional endovascular methods: A cohort study

Objective Posterior inferior cerebellar artery (PICA) aneurysms are uncommon and may be challenging to treat, especially if they are very small saccular or dissecting pseudoaneurysms at proximal and mid-PICA locations. They are usually technically difficult to treat with conventional reconstructive endovascular methods. We present our experience with PICA aneurysms treated by a stand-alone small, low-profile stent with a moderate flow-diverting effect (low-profile visualized intraluminal support junior (LVIS Jr)) compared to conventional endovascular methods. Methods Single institution cases of treated unruptured PICA aneurysms from 2015 to May 2022 were retrospectively reviewed. Patient characteristics, pre-and postoperative images, and last clinical and radiological outcomes were analyzed. Comparative statistical analysis was used. Results Nine cases of unruptured PICA aneurysms treated with stand-alone LVIS Jr (group 1) and seven cases treated with other conventional methods (group 2) were identified. The mean age was 56 versus 61.43 years, sex was female in 7 versus 6 cases, and the left side was involved in 7 versus 4 cases in group 1 and group 2, respectively. All aneurysms were in the proximal PICA segment except for one case in the mid-PICA segment aneurysm in each group. There was a difference in aneurysm type in both groups ( p = 0.008). All aneurysms were of saccular type except for five dissecting types in group 1 and 2 in group 2. The mean aneurysm size was 1.91 ± 0.62 in group 1 and 9.04 ± 5.82 mm in group 2 ( p < 0.0002). In group 2, treatment was with PICA sacrifice (one case), primary aneurysm coiling (three cases), stent-assisted coiling (one case), and flow diverter (two cases). Complications were only puncture site-related that occurred once in each group. There were no differences in mean clinical or radiological follow-up. Aneurysm recurrence with retreatment occurred in two cases in each group. All patients had an mRS 0–2 at the last follow-up. Conclusion In selected cases, unruptured small or dissecting PICA aneurysms may be treated safely and effectively using single stand-alone LVIS Jr. Prospective studies are needed to validate safety and efficacy.