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Title: P-023 Optimizing radial force of stent retrievers to minimize vessel wall injury: mechanical bench testing of radial force generated by a novel braided stent retriever compared to laser-cut stent retrievers in the M1 and m2 vessels
Purpose: Recent reports have raised various concerns about the risk of vessel wall injury while withdrawing current laser-cut stent retrievers during active strut apposition to the vessel walls. The development of braided thrombectomy assist devices in conjunction with aspiration systems may be gentler on the fragile brain vessels and more optimized with regard to the radial force (RF) for vessel diameters of proximal (M1) and distal (M2) large vessel occlusions (LVOs). Methods: Mechanical bench testing of the RF was performed using a radial compression station mounted on a tensile testing machine. The total RF in newtons (N) generated in vessels with diameters ranging from 2.25 to 3 mm as seen in proximal LVOs (∼M1), and in vessel diameters ranging from 1.5 to 2.24 mm as seen in distal LVOs (∼M2), was measured. The outer diameter of each stent was recorded, and an RF ≤1 N was grouped as “low,” while an RF > 1 N was grouped as “high” for this analysis. Results: The total RFs of all laser-cut stent retrievers were all higher in the simulated M2 vessels (> 1 N) than in the M1 vessels (< 1 N), whereas the total RFs of the braided thrombectomy assist devices were more » uniformly low in both the simulated M1 and the simulated M2 vessels. Conclusions: Novel braided thrombectomy assist devices in conjunction with aspiration systems have lower RFs than existing laser-cut stent retrievers in M1 and M2 vessel diameters. Further in vivo studies are needed to delineate the impact of lowering the RF on vessel wall integrity. Funding Source: This study was funded in part by a research grant (NSF Award: 1819491; PI: Vallabh Janardhan, MD) from the National Science Foundation (NSF). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. Conference Proceeding: This paper was presented in part at the 15th Annual Meeting of the Society of Neuro-Interventional Surgery (SNIS), July 23-26, 2018 in San Francisco, CA. « less
Authors:
; ; ;
Award ID(s):
1819491
Publication Date:
NSF-PAR ID:
10132842
Journal Name:
Journal of neurointerventional surgery
Volume:
10
Issue:
2
Page Range or eLocation-ID:
A37-A38
ISSN:
1759-8478
Sponsoring Org:
National Science Foundation
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