title: Reproducibility of image-based computational models of intracranial aneurysm: a comparison between 3D rotational angiography, CT angiography and MR angiography.
abstract: BACKGROUND
  Reconstruction of patient-specific biomechanical model of intracranial aneurysm has been based on different imaging modalities. However, different imaging techniques may influence the model geometry and the computational fluid dynamics (CFD) simulation. The aim of this study is to evaluate the differences of the morphological and hemodynamic parameters in the computational models reconstructed from computed tomography angiography (CTA), magnetic resonance angiography (MRA) and 3D rotational angiography (3DRA).
  
  
  METHODS
  Ten patients with cerebral aneurysms were enrolled in the study. MRA, CTA and 3DRA were performed on all patients. For each patient, three patient-specific models were reconstructed respectively based on the three sets of imaging data of the patient. CFD simulations were performed on each model. Model geometry and hemodynamic parameters were compared between the three models.
  
  
  RESULTS
  In terms of morphological parameters, by comparing CTA based models (CM) and 3DRA based models (DM) which were treated as the "standard models", the aspect ratio had the minimum difference (Δ = 8.3 ± 1.72 %, P = 0.953) and the surface distance was 0.25 ± 0.07 mm. Meanwhile, by comparing MRA based models (MM) and DM, the size had the minimum difference (Δ = 6.6 ± 1.85 %, P = 0.683) and the surface distance was 0.36 ± 0.1 mm. In respect of hemodynamic parameters, all three models showed a similar distribution: low average WSS at the sack, high OSI at the body and high average WSSG at the neck. However, there was a large variation in the average WSS (Δ = 34 ± 5.13 % for CM, Δ = 40.6 ± 9.21 % for MM).
  
  
  CONCLUSIONS
  CTA and MRA have no significant differences in reproducing intracranial aneurysm geometry. The CFD results suggests there might be some significant differences in hemodynamic parameters between the three imaging-based models and this needs to be considered when interpreting the CFD results of different imaging-based models. If we only need to study the main flow patterns, three types of image-based model might be all suitable for patient-specific computational modeling studies.
authors.affiliation: State Key Laboratory of Bioelectronics, Southeast University, Nanjing, 210096, P.R. China.|School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, P.R. China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, P.R. China.
authors.forename: Guo-Zhong
authors.initials: GZ
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Bioelectronics, Southeast University, Nanjing, 210096, P.R. China.|School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, P.R. China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Bioelectronics, Southeast University, Nanjing, 210096, P.R. China. landycaiyan@aliyun.com.|School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, P.R. China. landycaiyan@aliyun.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Cai
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, 210002, P.R. China. cjr.luguangming@vip.163.com.
authors.forename: Guang-Ming
authors.initials: GM
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Bioelectronics, Southeast University, Nanjing, 210096, P.R. China. zylicam@gmail.com.|School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, P.R. China. zylicam@gmail.com.|School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, QLD, 4001, Australia. zylicam@gmail.com.
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Li
mesh_terms: D000368:Aged; D000072226:Computed Tomography Angiography; D005260:Female; D006439:Hemodynamics; D006801:Humans; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D066230:Patient-Specific Modeling; D015203:Reproducibility of Results; D012399:Rotation
keywords: Aneurysm; Angiography; CFD; CTA; DSA; MRA; Reproducibility