Journal of Medical and Biological Engineering

, Volume 39, Issue 1, pp 27–42 | Cite as

A Computational Hemodynamics Analysis on the Correlation Between Energy Loss and Clinical Outcomes for Flow Diverters Treatment of Intracranial Aneurysm

  • Tin Lok ChiuEmail author
  • Abraham Yik Sau Tang
  • Anderson Chun On Tsang
  • Gilberto Ka Kit Leung
  • Kwok Wing Chow
Original Article


The rupture of intracranial aneurysms might lead to permanent disability or even death. One possible endovascular treatment is the deployment of flow diverters (FDs), which reduces flow into the sac and promotes thrombosis. Computational fluid dynamics simulations were used to assess the flow patterns and dynamics. The concept of energy loss, as a measure of necessary work done to overcome flow resistance, was utilized to correlate with clinical outcome. If a surgical operation is successful, the flow would be diverted to a shorter path and energy loss should be reduced. Conversely, persistent flow in the sac, associated with treatment failure, would display an increased energy loss as blood is then squeezed through the stent pores. Four illustrative clinical cases, involving both bifurcation and sidewall aneurysms, were selected. To reduce the numerical complexity, earlier works in the literature had used a porous medium approximation for the FDs. Here, the FD was simulated explicitly as a virtual (or computer-generated) stent, which would likely provide a more accurate description. Furthermore, quantitative comparisons between the approaches of virtual stenting and a porous medium with typical parameters were conducted by examining the effective flow influx into the aneurysm.


Intracranial aneurysms Computational fluid dynamics (CFD) Flow-diverter Energy loss 



Partial financial support was provided by the Innovation and Technology Support Program (ITS/150/15) of the Hong Kong Special Administrative Region Government.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflicts of interest.


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Copyright information

© Taiwanese Society of Biomedical Engineering 2018

Authors and Affiliations

  1. 1.The Department of Mechanical EngineeringUniversity of Hong KongPokfulamHong Kong
  2. 2.The Department of Surgery, Li Ka Shing Faculty of MedicineUniversity of Hong KongPokfulamHong Kong

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