213 Acute Flow Diversion for Ruptured Cerebral Aneurysms Arising From Vessels of Small Caliber Using FRED Jr: A Clinical Case Series

Abstract

INTRODUCTION: Ruptured aneurysms arising from small caliber (<2.5 mm) or distal vessels beyond the circle of Willis are considered challenging for all treatment modalities. Recently, the FRED Jr stent, designed for flow diversion in small arteries, was approved in the US for the treatment of non-ruptured aneurysms. METHODS: Clinical and radiological records of patients sustaining SAH treated with FRED Jr between June 2020 and October 2022 were reviewed. Treatment course including anti-platelet therapy, external ventricular drain (EVD) management, and vasospasm, as well as clinical outcomes were analyzed. Angiographic results were assessed according to the O’Kelly-Marotta (OKM) scale. RESULTS: Nine patients with at a median age of 62 (27-75) were included. The median Hunt Hess score was 2 (IQR 1) and modified Fischer score was 4 (IQR 1). Six aAneurysms’ morphologies included were saccular (6 case), 1 blister (1 case) and 2 were and dissecting (2 cases) type, located at the ACOM complex (3), A2/A3 (3), M2/M3 (1), V4 (1), and P2 (1) segments. All stents were deployed successfully with no intraprocedural complications. Post-operatively, no re-bleeding events were encountered. Vasospasm therapy was initiated in 6 cases, and no symptomatic EVD-related hematomas were observed. Post- operative ischemic events were encountered in 2 cases. Median 3-month mRS was 2 (IQR 1) for the7 surviving patients, and 3-months radiographic follow-up revealed OKM scale D in 4/7 cases. CONCLUSIONS: Flow diversion as a potential treatment strategy for acutely ruptured aneurysms arising from small caliber vessels is feasible using FRED Jr. Since As the complication profile reported in this series is comparable to historical microsurgical cohorts and effective protection was conferred by this treatment modality, our small cohort provides a glimpse into acute flow diversion for this subset of difficult-to-treat aneurysms.