A 4DCT imaging-based breathing lung model with relative hysteresis (original) (raw)

Modeling Airflow Using Subject-Specific 4DCT-Based Deformable Volumetric Lung Models

International journal of biomedical imaging, 2012

Lung radiotherapy is greatly benefitted when the tumor motion caused by breathing can be modeled. The aim of this paper is to present the importance of using anisotropic and subject-specific tissue elasticity for simulating the airflow inside the lungs. A computational-fluid-dynamics (CFD) based approach is presented to simulate airflow inside a subject-specific deformable lung for modeling lung tumor motion and the motion of the surrounding tissues during radiotherapy. A flow-structure interaction technique is employed that simultaneously models airflow and lung deformation. The lung is modeled as a poroelastic medium with subject-specific anisotropic poroelastic properties on a geometry, which was reconstructed from four-dimensional computed tomography (4DCT) scan datasets of humans with lung cancer. The results include the 3D anisotropic lung deformation for known airflow pattern inside the lungs. The effects of anisotropy are also presented on both the spatiotemporal volumetric ...

Lung mesh generation to simulate breathing motion with a finite element method

International Conference on Information Visualisation, 2004

Numerical modelling of lung behaviour during the respiration cycle is a difficult challenge due to its complex geometry and surrounding environment constraints. This paper presents an approach to simulate a patient's lung motion during inhaling and exhaling based on a continuous media mechanics model and solved with a finite element method. One of the key problems is an adequate lung

Fluid structure interaction in lower airways of CT-based lung geometries

International Journal for Numerical Methods in Fluids, 2008

In this study, the deformability of airway walls is taken into account to study airflow patterns and airway wall stresses in the first generations of lower airways in a real lung geometry. The lung geometry is based on CT scans that are obtained from in vivo experiments on humans. A partitioned fluid–structure interaction (FSI) approach, realized within a parallel in-house finite element code, is employed. It is designed for the robust and efficient simulation of the interaction of transient incompressible Newtonian flows and (geometrically) non-linear airway wall behavior. Arbitrary Lagrangian–Eulerian-based stabilized tetrahedral finite elements are used for the fluid and Lagrangian-based 7-parametric mixed/hybrid shell elements are used for the airway walls using unstructured meshes due to the complexity of the geometry. Airflow patterns as well as airway wall stresses in the bronchial tree are studied for a number of different scenarios. Thereby, both models for healthy and diseased lungs are taken into account and both normal breathing and mechanical ventilation scenarios are studied. Copyright © 2008 John Wiley & Sons, Ltd.

An adaptive driver and real-time deformation algorithm for visualization of high-density lung models

Studies in health technology and informatics, 2004

Technological advances in Augmented Reality (AR) and extraction of 3D patient specific medical data led to the creation of medical visualization using AR environments, in which the 3D data is registered and synchronized with the position of the patient. One of the challenges in such visualization environments is maintaining an accurate shape of the 3D data for self-deformable models such as lungs. An accurate deformation of lung model with 3D visualization may significantly increase the teaching and diagnosing ability of physicians. Modeling the deformation of lungs primarily involves the accurate representation of Pressure-volume relationship and the hysteresis in the relationship during inhalation and exhalation. This paper explains a real-time physiologically accurate deformation algorithm and its hardware rendering. We then introduce a novel approach for the representation of accurate pressure volume relationship based on an analogy with classical mechanics. Our simulation resul...