Biological Fluid Dynamics – Computational Fluid Dynamics (CFD)

The dynamics of fluids flowing through a human body can have a significant effect on the overall health of a person. Unobstructed flow in the respiratory system ensures the delivery of enough oxygen to the blood. Various pulmonary diseases like asthma or COPD may affect this process. The same principles hold for all body fluids like for instance blood. Obstructions or alterations of blood flows can lead to heart attack, aneurysms, etc.

The behaviour of fluids can be described through mathematical equations called Navier-Stokes equations. If the patient’s geometry (his lungs, arteries, heart, etc) and the so-called boundary conditions (blood flow velocity, airflow pressures,etc) can also be prescribed accurately then a patient specific model can be constructed that allows for highly detailed, functional imaging. The functional imaging consists of solving the Navier Stokes equations numerically, this method is called Computational Fluid Dynamics (CFD). Using this functional imaging it is possible to perform different interventions or analyse different treatments in order to select the optimal one for the patient. This method is cost efficient and ensures the best possible patient comfort.

This method can be applied to for instance:

• Ventilation assesment of the respiratory system [1]
• Particle deposition of inhalation therapies
• Assessment of local interventions for snoring and sleep apnea [2]
• Virtual surgery for nasal septum corrections
• Analyses of mechanical devices (valves, stents,…) in bronchi, veins and arteries [3]

Having a sound understanding of the problem at hand and being able to apply correct boundary conditions is crucial for the computational fluid dynamics model. In the biomedical field, especially for complex in-patient modelling, this principle is even more important compared to the other industries where one uses CFD. FluidDA creates an environment where a close cooperation exists between healthcare experts with many years of clinical experience and experts in the field of numerical modelling, this to ensure a high quality standard.

[1] J.W. De Backer, W.G. Vos, A. Devolder, S.L. Verhulst, P. Germonpre, F.L. Wuyts, P.M. Parizel, W. De Backer; Computational fluid dynamics can detect changes in airway resistance in asthmatics after acute bronchodilation; J Biomech 2008;41(1):106-13.

[2] J.W. De Backer, O.M. Vanderveken, W.G. Vos, A. Devolder, S.L. Verhulst, J.A. Verbraecken, P.M. Parizel, M.J. Braem, P.H. Van de Heyning, W.A. De Backer; Functional imaging using computational fluid dynamics to predict treatment success of mandibular advancement devices in sleep-disordered breathing; J. Biomech 2007;40(16):3708-14.

[3] Dumont K, Vierendeels J, Kaminsky R, van Nooten G, Verdonck P, Bluestein D; Comparison of the hemodynamic and thrombogenic performance of two bileaflet mechanical heart valves using a CFD/FSI model.; J. Biomech Engineering 2007 Aug;129(4):558-65