Cerebral aneurysms treated with flow-diverting stents: computational models with intravascular blood flow measurements

• Published in: American journal of neuroradiology : AJNR 2014-01, Vol.35 (1), p.143-148
• Main Authors: Levitt, M R, McGah, P M, Aliseda, A, Mourad, P D, Nerva, J D, Vaidya, S S, Morton, R P, Ghodke, B V, Kim, L J
• Format: Article
• Language: English
• Subjects: Adult; Blood Flow Velocity; Blood Pressure; Blood Vessel Prosthesis; Cerebral Arteries - physiopathology; Cerebral Arteries - surgery; Cerebrovascular Circulation; Computer Simulation; Equipment Failure Analysis; Female; Humans; Interventional; Intracranial Aneurysm - diagnosis; Intracranial Aneurysm - physiopathology; Intracranial Aneurysm - surgery; Male; Models, Cardiovascular; Models, Neurological; Prosthesis Failure; Statistics as Topic; Stents; Treatment Outcome
• ISSN: 0195-6108; 1936-959X
• DOI: 10.3174/ajnr.A3624

Computational fluid dynamics modeling is useful in the study of the hemodynamic environment of cerebral aneurysms, but patient-specific measurements of boundary conditions, such as blood flow velocity and pressure, have not been previously applied to the study of flow-diverting stents. We integrated patient-specific intravascular blood flow velocity and pressure measurements into computational models of aneurysms before and after treatment with flow-diverting stents to determine stent effects on aneurysm hemodynamics. Blood flow velocity and pressure were measured in peri-aneurysmal locations by use of an intravascular dual-sensor pressure and Doppler velocity guidewire before and after flow-diverting stent treatment of 4 unruptured cerebral aneurysms. These measurements defined inflow and outflow boundary conditions for computational models. Intra-aneurysmal flow rates, wall shear stress, and wall shear stress gradient were calculated. Measurements of inflow velocity and outflow pressure were successful in all 4 patients. Computational models incorporating these measurements demonstrated significant reductions in intra-aneurysmal wall shear stress and wall shear stress gradient and a trend in reduced intra-aneurysmal blood flow. Integration of intravascular dual-sensor guidewire measurements of blood flow velocity and blood pressure provided patient-specific computational models of cerebral aneurysms. Aneurysm treatment with flow-diverting stents reduces blood flow and hemodynamic shear stress in the aneurysm dome.