International Journal for Numerical Methods in Biomedical Engineering

Cover image for Vol. 29 Issue 4

April 2013

Volume 29, Issue 4

Pages 445–559

  1. Research Articles

    1. Top of page
    2. Research Articles
    1. Lagrangian analysis of hemodynamics data from FSI simulation (pages 445–461)

      Vincent Duvernois, Alison L. Marsden and Shawn C. Shadden

      Article first published online: 18 OCT 2012 | DOI: 10.1002/cnm.2523

      Thumbnail image of graphical abstract

      We present the computation of Lagrangian-based flow characterization measures for time-dependent, deformable-wall, finite-element blood flow simulations. The algorithm is demonstrated in a fluid-structure interaction simulation of blood flow through a total cavopulmonary connection, and results are compared with a rigid-vessel simulation. Overall, strong similarity in Lagrangian measures of the flow between deformable and rigid-vessel models was observed.

    2. Numerical simulation of particle dynamics in an orifice–electrode system. Application to counting and sizing by impedance measurement (pages 462–475)

      Damien Isèbe and Philippe Nérin

      Article first published online: 12 NOV 2012 | DOI: 10.1002/cnm.2528

      Thumbnail image of graphical abstract

      In most cases, counting and sizing of biological cells are based on electrical gating through a microorifice in a close orifice-electrode system that we don't experimentally apprehend. In this framework, we have developed a complete numerical approach to compute the exact particle size distribution by taking into account the trajectory and the orientation of the particles through the microorifice. This numerical approach is fully innovative in diagnosis engineering and can be used to perform particle sizing measurement by optimizing shape design or fluidic conditions.

    3. Hemodynamics analysis of patient-specific carotid bifurcation: A CFD model of downstream peripheral vascular impedance (pages 476–491)

      Jingliang Dong, Kelvin K.L. Wong and Jiyuan Tu

      Article first published online: 21 NOV 2012 | DOI: 10.1002/cnm.2529

      Thumbnail image of graphical abstract

      The main purpose of this paper is to establish a feasible and efficient hemodynamics framework through connecting two porous domains with different transient permeability configurations to outlets of truncated carotid bifurcation subjects to represent different downstream peripheral vascular impedance (DPVI) effects on the intravascular blood flow patterns. Once carotid models were mounted into a standard hemodynamic environment with the same DPVI configuration, the influence of stenosis-induced flow resistance variation on intravascular flow patterns can be accessed.

    4. The biomechanics of the human tongue (pages 492–514)

      Yaseen Kajee, J-P. V. Pelteret and B. D. Reddy

      Article first published online: 14 JAN 2013 | DOI: 10.1002/cnm.2531

      Thumbnail image of graphical abstract

      A fully linearised, small-strain FEM model of active human skeletal muscle is demonstrated in the context of obstructive sleep apnoea research through modelling the behaviour of the human tongue. A realistic tongue geometry, derived from the Visible Human Project, is presented in conjunction with the underlying microscopic fibre data. A number of benchmark models are presented, after numerous scenarios involving deformation due to gravitational loading and active muscle contraction are discussed.

    5. Design of vascular networks: A mathematical model approach (pages 515–529)

      Jian Yang and Yongtian Wang

      Article first published online: 6 DEC 2012 | DOI: 10.1002/cnm.2534

      Thumbnail image of graphical abstract

      This paper presents novel methods for modeling realistic vascular tree in 3D space and for calculating hemodynamics throughout the simulated tree structures. The generated vascular tree not only follows the power law relationship but also maximizes the filling volume in 3D space. From the hemodynamic calculations, the processes for which structural changes affect hemodynamic distributions are studied in detail.

    6. Effect of choroidal blood perfusion and natural convection in vitreous humor during transpupillary thermotherapy (TTT) (pages 530–541)

      Arunn Narasimhan and C. Sundarraj

      Article first published online: 16 JAN 2013 | DOI: 10.1002/cnm.2538

      Thumbnail image of graphical abstract

      Two-dimensional computational model of human eye for simulating transpupillary thermotherapy process is developed and a finite volume-based numerical methodology is used. Natural convection in vitreous humor and choroidal blood perfusion showed significant effect on the temperature distribution inside the human eye. Increased thermal damage occurred in the nearby regions of retinal laser spot compared with the spot location itself, due to the convective flow of vitreous.

    7. Cellular automata coupled with steady-state nutrient solution permit simulation of large-scale growth of tumours (pages 542–559)

      Sachin Man Bajimaya Shrestha, Grand Roman Joldes, Adam Wittek and Karol Miller

      Article first published online: 5 FEB 2013 | DOI: 10.1002/cnm.2539

      Thumbnail image of graphical abstract

      We present a novel, computationally very efficient hybrid algorithm for the simulation of complete growth of comprehensive avascular tumour model that takes into account proliferation, quiescence, necrosis, intercellular adhesion, and phenotypical evolution of cells and the oxygen distribution inside the tumour volume that is described by using time-independent solution, which is shown to be almost equivalent to time-dependent solution, and we demonstrate that the cell cycle time, growth fraction, volume doubling time, and cell loss factor are in good agreement with experimental results.