A Study of the Relationship between the Microcatheter Shape and Stability by Numerical Simulation

Abstract

Objective: The stability of the microcatheter is important in safe coil deployment. However, quantitative information regarding the relationship between the microcatheter shape and stability is limited. We investigated deformation characteristics of the microcatheter by applying loads to the tip of a placed microcatheter using numerical analysis. Materials and Methods:Microcatheter models were prepared by connecting cylindrical rigid segments with coil springs.Four types of models with shapes mimicking parts of a blood vessel and three types of models with shapes that come into contact with the vascular wall on the opposite side of the aneurysm were prepared. Results:When the distance between the tip of the microcatheter and the position of its contact with the vascular wall exceeded 12 mm, the suppressive effect on displacement of the microcatheter tip was markedly reduced. When this distance was less than 6 mm, the microcatheter shape exerted a greater effect on the stability than the distance. Conclusion:These results suggest that not only the position of contact of the microcatheter with the vascular wall but also the shape of the microcatheter near the aneurysm plays an important role in securing the stability.

Evaluation of Contact Force between Aneurysm Model and Coil for Embolization of Intracranial Aneurysms

“…On the other hand, the behaviors of coils, microcatheters and guidewires have been evaluated using various methods such as numerical analysis and experiments with a blood vessel biomodel. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] However, few studies have assessed the contact state between a coil and aneurysm. 11) In this study, a coil was inserted into an aneurysm biomodel consisting of silicone rubber through a catheter using an experimental system that we developed, and the contact force on coil-frame formation was measured using a force sensor attached to the model.…”

Evaluation of effect of aneurysm model material on coil contact force and catheter movement

“…For example, in clinical situations, they make decisions about where to place the microcatheter in the aneurysm and which coil to use through a trial and error process. Various methods have been applied to investigate coil and microcatheter behavior using numerical analysis (Chiang et al, 2013;Fujimura et al, 2018;Morales et al, 2013;Otani et al, 2015;Takashima et al, 2017Takashima et al, , 2014Takashima et al, , 2009Takashima et al, , 2007Takashima et al, , 2006Toma et al, 2017). Moreover, experiments using blood vessel biomodels made of silicone rubber (Haraguchi et al, 2013;Ikeda et al, 2005;Matsunaga et al, 2017;Nagano et al, 2010;Takashima et al, 2021), acryl (Lamano et al, 2014) or poly (vinyl alcohol) hydrogel (PVA-H) (Haga et al, 2020;Kosukegawa et al, 2008;Ohta et al, 2004;Takashima et al, 2017Takashima et al, , 2014, mimicking living tissue, have been conducted.…”