Development of Cerebral Aneurysms' A Prediction Model

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Development of Cerebral Aneurysms. A Prediction
Model
Ihor Machyshyn
Supervisors
Dr. Ir. P.M.J. Rongen (Philips Medical
Systems) Dr. Ir. A.A.F. van de Ven (TU/e,
WI) Dr. Ir. S.J.L. van Eijndhoven (TU/e,
WI) Prof. Dr. Ir. F.N. van de Vosse (TU/e,
BMT) Dr. Ir. P.H.M. Bovendeerd (TU/e, BMT)
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3D Rotational Angiography (3D-RA)

• Combined X-ray images into a 3D view

safe?
dangerous?
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Approaches to assess risk of rupture

• Current clinical practice (based on geometry)
• Mechanical analysis
• Hemodynamical approach
• Vessel wall mechanics
• Stress and strain estimation
• Adaptation of the tissue
• Rupture criterion

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Goal of the project

• Develop a model that uses realistic description
  of aneurysmal tissue
• Study growth of cerebral aneurysms

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Blood Vessel Histology
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Model
Variables
Collagen
- collagen stretch
- recruitment
- collagen thickness
- attachment collagen stretch
Elastin
- elastin (tissue) stretch
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Equations Governing Mechanics

• Constitutive equation

with

• Equation of equilibrium

• Incompressibility equation

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Evolution Equations of Remodeling

• Equations of remodeling

with
- rate constants of remodeling

• Initial conditions

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Healthy State of an Artery
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Transition between States
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Remodeling to a Healthy State
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Visualization of Instability
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Stability of Equilibrium ((e)) States
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Analysis of Stability of an Equilibrium State of
a Thin-walled cylinder. Equations
where
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Method
satisfy equations on the previous slide
Stability condition
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Result