Journal of Hydrodynamics

, Volume 28, Issue 3, pp 462–472 | Cite as

A joint computational-experimental study of intracranial aneurysms: Importance of the aspect ratio

  • Simon Sui-Man Lai
  • Abraham Yik-Sau TangEmail author
  • Anderson Chun-On Tsang
  • Gilberto Ka-Kit Leung
  • Alfred Cheuk-Hang Yu
  • Kwok Wing Chow


Rupture of a cerebral aneurysm (abnormal swelling of blood vessel in the brain) will cause subarachnoid hemorrhage, and will result in an alarming rate of mortality and morbidity. A joint computational-experimental study is conducted to assess the importance of the aspect ratio in the dynamics of blood flow. The aspect ratio is defined here to be the ratio of the height of the aneurysm to the linear dimension of the neck. Idealized models of such aneurysms located near a bifurcation point were investigated. Numerical simulations for hemodynamic properties like shear stress and flow rate were performed. The computational results were verified experimentally with specially fabricated phantoms, blood mimicking fluid and Doppler ultrasound imaging. Excellent agreements were obtained. Two features are highlighted, providing information in the intensely debated link between rupture risk and geometric factors. On increasing the aspect ratios, firstly, a jet impinging on the distal part of the neck can be observed, and secondly, a region of positive shear stress gradient can be found there. Furthermore, computational analyses for four patient-specific models were conducted to correlate with the results of idealized models and to provide further clinical insight.

Key words

intracranial aneurysms aspect ratio Doppler ultrasound 


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Copyright information

© China Ship Scientific Research Center 2016

Authors and Affiliations

  • Simon Sui-Man Lai
    • 1
  • Abraham Yik-Sau Tang
    • 2
    Email author
  • Anderson Chun-On Tsang
    • 3
  • Gilberto Ka-Kit Leung
    • 3
  • Alfred Cheuk-Hang Yu
    • 4
  • Kwok Wing Chow
    • 2
  1. 1.Department of Electrical and Electronic EngineeringUniversity of Hong KongHong Kong, China
  2. 2.Department of Mechanical EngineeringUniversity of Hong KongHong Kong, China
  3. 3.Department of Surgery, Li Ka Shing Faculty of MedicineUniversity of Hong KongHong Kong, China
  4. 4.Department of Electrical and Computer EngineeringUniversity of WaterlooCanada

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