Abstract DP322: Comparison of Lattice Flow Diverter and Pipeline Embolization Device in Unruptured Intracranial Aneurysms: A Real-World, Propensity Score-Matching Study

Background and Objectives: Flow diverters (FDs) have been increasingly used in treating unruptured intracranial aneurysms (UIAs). However, comparative studies between the novel Lattice Flow Diverter (LFD), characterized by the MIROR (metal interface reassembly for optimizing restenosis) surface modification technology and an innovative delivery system equipped with a self-expanding mechanical balloon, and other FDs are limited. Our study aimed to compare outcomes of LFD and Pipeline Embolization Device (PED) Flex for UIAs using propensity score matching (PSM). Methods: Patients with UIAs treated with LFD or PED between August 2023 and November 2024 were included. PSM was performed to adjust for age, sex, comorbidities, ischemic stroke history, smoking status, alcohol abuse, preoperative modified Rankin Scale scores, history of multiple aneurysms, aneurysm characteristics, adjunctive coiling, and angiographic follow-up duration. Perioperative complications and clinical and angiographic outcomes were compared after matching. Results: 99 patients treated by LFD and 187 patients treated by PED were included. The complete occlusion rate of LFD treatment for UIAs was comparable with PED (82.8% vs 85%, p=0.753; meidan angiographic follow-up time, 216 d vs 215 d, p=0.514). Compared to the PED group, the LFD group had fewer females (65.7% vs 77.5%, p=0.043), more patients with a history of multiple aneurysms (28.3% vs 12.3%, p<0.001), wider aneurysm necks (4.26 mm vs 3.92 mm, p=0.036), shorter stent lengths (p<0.001), and lower rates of in-stent stenosis (ISS) (stenosis>50%) (3.0% vs 11.2%, p=0.031). After PSM, 55 matched pairs were analyzed. The LFD group demonstrated significantly lower ISS rates (1.8% vs. 14.5%, p=0.037), with no significant differences in perioperative complications, the complete occlusion rate at the median 216-day angiographic follow-up (87.3% vs 85.5%, p>0.999), or favorable outcomes (mRS 0-2, 96.4% vs 94.5%, p>0.999) compared to the PED group after PSM analysis. Conclusion: The mechanical balloon-based LFD with surface modification showed a lower ISS rate and comparable perioperative outcomes, short-term occlusion rates, and clinical prognosis compared with PED. The advantages brought by the innovation of LFD warrant further validation through long-term randomized controlled trials.