title: Angiographic analysis for phantom simulations of endovascular aneurysm treatments with a new fully retrievable asymmetric flow diverter.
abstract: Digital Subtraction Angiography (DSA) is the main diagnostic tool for intracranial aneurysms (IA) flow-diverter (FD) assisted treatment. Based on qualitative contrast flow evaluation, interventionists decide on subsequent steps. We developed a novel fully Retrievable Asymmetric Flow-Diverter (RAFD) which allows controlled deployment, repositioning and detachment achieve optimal flow diversion. The device has a small low porosity or solid region which is placed such that it would achieve maximum aneurysmal in-jet flow deflection with minimum impairment to adjacent vessels. We tested the new RAFD using a flow-loop with an idealized and a patient specific IA phantom in carotid-relevant physiological conditions. We positioned the deflection region at three locations: distally, center and proximally to the aneurysm orifice and analyzed aneurysm dome flow using DSA derived maps for mean transit time (MTT) and bolus arrival times (BAT). Comparison between treated and untreated (control) maps quantified the RAFD positioning effect. Average MTT, related to contrast presence in the aneurysm dome increased, indicating flow decoupling between the aneurysm and parent artery. Maximum effect was observed in the center and proximal position (~75%) of aneurysm models depending on their geometry. BAT maps, correlated well with inflow jet direction and magnitude. Reduction and jet dispersion as high as about 50% was observed for various treatments. We demonstrated the use of DSA data to guide the placement of the RAFD and showed that optimum flow diversion within the aneurysm dome is feasible. This could lead to more effective and a safer IA treatment using FDs.
authors: Department of Biomedical Engineering, State University of New York at Buffalo; Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: Aradhana
authors: A
authors: Yoganand
authors: Department of Biomedical Engineering, State University of New York at Buffalo; Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: Rachel P
authors: RP
authors: Wood
authors: Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo; University of Antioquia-GIB-Eafit, Medellin, Colombia.
authors: Carlos
authors: C
authors: Jimenez
authors: Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: Adnan
authors: A
authors: Siddiqui
authors: Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: Kenneth
authors: K
authors: Snyder
authors: Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: S V Setlur
authors: SV
authors: Nagesh
authors: Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: D R
authors: DR
authors: Bednarek
authors: Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: S
authors: S
authors: Rudin
authors: Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: Robert
authors: R
authors: Baier
authors: Department of Biomedical Engineering, State University of New York at Buffalo; Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
authors: Ciprian N
authors: CN
authors: Ionita
keywords: Asymmetric flow diverter (AFD); Bolus arrival time (BAT); Digital subtraction angiography (DSA); Flow diverter (FD); Intracranial aneurysm (IA); Mean transit time (MTT); Retrievable asymmetric flow diverter (RAFD); Uniform flow diverter (UFD); parametric image mapping (PIM)