title: Computational Hemodynamic Analysis for the Diagnosis of Atherosclerotic Changes in Intracranial Aneurysms: A Proof-of-Concept Study Using 3 Cases Harboring Atherosclerotic and Nonatherosclerotic Aneurysms Simultaneously.
abstract: This was a proof-of-concept computational fluid dynamics (CFD) study designed to identify atherosclerotic changes in intracranial aneurysms. We selected 3 patients with multiple unruptured aneurysms including at least one with atherosclerotic changes and investigated whether an image-based CFD study could provide useful information for discriminating the atherosclerotic aneurysms. Patient-specific geometries were constructed from three-dimensional data obtained using rotational angiography. Transient simulations were conducted under patient-specific inlet flow rates measured by phase-contrast magnetic resonance velocimetry. In the postanalyses, we calculated time-averaged wall shear stress (WSS), oscillatory shear index, and relative residence time (RRT). The volume of blood flow entering aneurysms through the neck and the mean velocity of blood flow inside aneurysms were examined. We applied the age-of-fluid method to quantitatively assess the residence of blood inside aneurysms. Atherosclerotic changes coincided with regions exposed to disturbed blood flow, as indicated by low WSS and long RRT. Blood entered aneurysms in phase with inlet flow rates. The mean velocities of blood inside atherosclerotic aneurysms were lower than those inside nonatherosclerotic aneurysms. Blood in atherosclerotic aneurysms was older than that in nonatherosclerotic aneurysms, especially near the wall. This proof-of-concept study demonstrated that CFD analysis provided detailed information on the exchange and residence of blood that is useful for the diagnosis of atherosclerotic changes in intracranial aneurysms.
authors.affiliation: Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan; Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan; Department of Neuroanesthesia, Kohnan Hospital, Sendai, Japan.
authors.forename: Shin-Ichiro
authors.identifier: 0000-0002-0406-8307
authors.initials: SI
authors.lastname: Sugiyama
authors.affiliation: Department of Neurosurgery, Kohnan Hospital, Sendai, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Endo
authors.affiliation: Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Kuniyasu
authors.initials: K
authors.lastname: Niizuma
authors.affiliation: Department of Neurosurgery, Kohnan Hospital, Sendai, Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Endo
authors.affiliation: Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Funamoto
authors.affiliation: Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan; Institute of Fluid Science, Tohoku University, Sendai, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Ohta
authors.affiliation: Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Teiji
authors.initials: T
authors.lastname: Tominaga
mesh_terms: D000368:Aged; D001158:Arteries / Q000503:physiopathology; D050197:Atherosclerosis / Q000150:complications / Q000503:physiopathology*; D002533:Cerebral Angiography; D003198:Computer Simulation; D005260:Female; D006439:Hemodynamics; D006801:Humans; D057446:Hydrodynamics; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000150:complications / Q000503:physiopathology*; D008055:Lipids / Q000737:chemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D008858:Microscopy, Phase-Contrast; D008875:Middle Aged; D015233:Models, Statistical; D009991:Oscillometry; D000072417:Protein Domains; D033081:Shear Strength; D013314:Stress, Mechanical
chemical_list: D008055:Lipids