Hemodynamic Effects of Stent-Induced Straightening of Parent Artery vs. Stent Struts for Intracranial Bifurcation Aneurysms

Abstract

ObjectiveThis study aims to compare the hemodynamic impact of stent-mesh and stent-induced straightening of the parent artery in intracranial bifurcation aneurysms using finite element method simulation.Material and MethodsThree intracranial bifurcation aneurysms treated with different stent-assisted coil embolization were evaluated. Simulation using the finite element method was conducted for Solitaire, LVIS and Neuroform stents. Four models of each stent were established, including a pre-treatment baseline, stenting without parent artery straightening (presented as stent-mesh effect), no-stent with parent artery reconstruction (to reveal the straightening impact), and stenting with straightening (categorized as Models I–IV respectively). Hemodynamic characteristics of the four models for each stent were compared.ResultsIn the Neuroform stent, compared with the pre-treatment model (100%), the mean WSS decreased to 82.3, 71.4, and 57.0% in Models II-IV, velocity to 88.3, 74.4, and 62.8%, and high flow volume (HFV, >0.3 m/s) to 77.7, 44.0, and 19.1%. For the LVIS stent, the mean WSS changed to 105.0, 40.2, and 39.8% in Models II to IV; velocity to 91.2, 58.1, and 52.5%, and HFV to 92.0, 56.1, and 43.9%. For the Solitaire stent, compared with the pre-treatment model (100%), the mean WSS of Models II-IV changed altered by 105.7, 42.6, and 39.4%, sac-averaged velocity changed to 111.3, 46.6, and 42.8%, and HFV 115.6, 15.1, and 13.6%.ConclusionThe hemodynamic effect of straightening the parent artery of intracranial bifurcation aneurysms by stenting was noticeably improved over stent mesh diversion in all three stents tested. Therefore stent-induced remodeling of the parent artery appears to be the best method of decreasing recurrence in intracranial bifurcation aneurysms.

Enterprise Treatment for Recurrent Basilar Tip Aneurysm after PulseRider-assisted Coil Embolization: A Case Report

“… 14 ) Therefore, straightening the parent artery with a stent may be the optimal way to reduce the recurrence of intracranial bifurcation aneurysms. 13 ) It has also been reported that parent artery straightening is likely to be involved in higher occlusion rates in flow-diverter stents. 15 ) Specifically, it has been shown that a vessel angle of 20° or more likely indicates stable aneurysms, regardless of neck or aneurysm size.…”

“…The hemodynamic effects of intracranial bifurcation aneurysms have been reported to be significantly improved by straightening the parent artery with flow diversion by metallic coverage. 13 ) Vascular straightening by stenting dramatically alters apex hemodynamics in a favorable direction by blunting apical pressure, including the narrowing and migration of the flow impingement zone. 14 ) Therefore, straightening the parent artery with a stent may be the optimal way to reduce the recurrence of intracranial bifurcation aneurysms.…”

“… 13 , 18 ) Therefore, Enterprise 2-induced remodeling of the BTA aneurysm appears to be the better method for decreasing recurrence after PulseRider placement. 13 ) Because PulseRider has low metal coverage, the risk of thrombus formation is low and there is a high possibility that even if a stent is added, it can be treated with the same antiplatelet therapy as that after normal single-stent placement. 3 , 5 )…”

How does the recurrence-related morphology characteristics of the Pcom aneurysms correlated with hemodynamics?

“…Kim et al ( 30 ) reported an outer curve aneurysm with lower vascular tortuosity was more similar to a bifurcation aneurysm and more likely to recur. Leng et al ( 31 ) and Wan et al ( 32 ) both pointed out that better hemodynamic changes can be achieved by using stents to straighten blood vessels. The risk of recurrence can be reduced by weakening the hemodynamic characteristics of bifurcation aneurysms, which was also consistent with our research.…”

Flow diversion effect of the leo braided stent for aneurysms in the posterior and distal anterior circulations: A multicenter cohort study

“…Intraoperative aneurysm rupture is one of the significant risk factors for early serious complications ( 17 ), and the risk of intraprocedural rupture is significantly high during coiling, especially in heteromorphic or very small aneurysms ( 31 , 32 ). Flow velocity in the aneurysm and wall shear stress are two important hemodynamic parameters associated with the growth and rupture of intracranial aneurysms ( 7 , 8 ), and could be eliminated by coiling the aneurysm more intuitively ( 33 , 34 ). In our study, two cases with acute cerebral hemorrhage were all in the SAC group, in our experience, complicated aneurysms treated with Leo-assisted coiling could not be packed too densely.…”