title: Influence of Parent Artery Segmentation and Boundary Conditions on Hemodynamic Characteristics of Intracranial Aneurysms.
abstract: OBJECTIVE
  The purpose of this study is to explore the influence of segmentation of the upstream and downstream parent artery and hemodynamic boundary conditions (BCs) on the evaluated hemodynamic factors for the computational fluid dynamics (CFD) analysis of intracranial aneurysms.
  
  
  METHODS
  Three dimensional patient-specific aneurysm models were analyzed by applying various combinations of inlet and outlet BCs. Hemodynamic factors such as velocity pattern, streamline, wall shear stress, and oscillatory shear index at the systolic time were visualized and compared among the different cases.
  
  
  RESULTS
  Hemodynamic factors were significantly affected by the inlet BCs while there was little influence of the outlet BCs. When the inlet length was relatively short, different inlet BCs showed different hemodynamic factors and the calculated hemodynamic factors were also dependent on the inlet length. However, when the inlet length (L) was long enough (L>20D, where D is the diameter of inlet section), the hemodynamic factors became similar regardless of the inlet BCs and lengths. The error due to different inlet BCs was negligible. The effect of the outlet length on the hemodynamic factors was similar to that of the inlet length.
  
  
  CONCLUSIONS
  Simulated hemodynamic factors are highly sensitive to inlet BCs and upstream parent artery segmentation. The results of this work can provide an insight into how to build models and to apply BCs for more accurate estimation of hemodynamic factors from CFD simulations of intracranial aneurysms.
authors.affiliation: Department of Mechanical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Hua
authors.affiliation: Department of Mechanical Engineering, Hanyang University, Seoul, Korea.
authors.forename: Je Hoon
authors.initials: JH
authors.lastname: Oh
authors.affiliation: Department of Neurosurgery, Cerebrovascular Center, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. ybkim69@yuhs.ac.
authors.forename: Yong Bae
authors.initials: YB
authors.lastname: Kim
mesh_terms: D000328:Adult; D001158:Arteries; D001783:Blood Flow Velocity; D006439:Hemodynamics; D006801:Humans; D057446:Hydrodynamics; D002532:Intracranial Aneurysm / Q000503:physiopathology*; D008955:Models, Cardiovascular; D013314:Stress, Mechanical
keywords: Intracranial aneurysms; boundary conditions; computational fluid dynamics; hemodynamic factors; parent artery segmentation