Page 44 - Computational Modeling in Biomedical Engineering and Medical Physics

30 Computational Modeling in Biomedical Engineering and Medical Physics

rate of growth, shape, structure. At this point, allometry may enter scene and join the
design group as a design criterion. Moreover, the geometry of the computational
domain should be consistent with the constructal law predictions and allometric laws,
if available. Chapter 2: Shape and Structure Morphing of Systems with Internal Flows
is devoted to this topic, and Chapters 5 8 present models that utilize this approach to
construct the computational domains.

Medical image-based construction, CAD and fused computational
domains
Realistic computational models envisage the real shape and structure of the
body and its anatomic content, the different tissues and their properties. It is an impor-
tant asset for getting meaningful results to medical problems, from the numerical simula-
tion perspective. Image acquisition scanners used in Computing Tomography (CT),
Magnetic Resonance Imaging (MRI), Ultrasound Imagery (USI) provide personalized
image sets of 2D slices, average images of 3D thin volumes in the DICOM (Digital
Imaging and Communications in Medicine) specific medical format. The image source
dataset that is used, in general, for preoperatory reasons, provides here the basis for con-
structing the computational domain (Morega et al., 2010, 2016). Specialized software
uses them as input data in the construction of the computational domain with the inter-
nal anatomy connections. Personalized construction of the anatomical structure is key
to the patient centered therapeutic approach and the accurate representation of the
anatomical organs and tissues morphology is crucial for the utility numerical modeling.
Chapter 2: Shape and Structure Morphing of Systems with Internal Flows is devoted to
this topic, and Chapters 4, 5, 7, 8 present models that utilize this approach to construct
the computational domains.
When the computational domains combine anatomic structures with CAD
elements—electrodes, transducers, prostheses, devices, sources, etc.—it is necessary to
combine CAD blocks with MIR structures into a complex, numerically consistent
model. This fusion may raise difficulties and it is a matter of the designer to opt for
the best, more often, available solution. Concerns and results regarding this design
approach are presented in Chapter 2: Shape and Structure Morphing of Systems with
Internal Flows. Several computational domains introduced in Chapters 5 8 are con-
structed using image fusion techniques.

1.11 Diffusion convection problems: heatfunction and massfunction

Scalar fields, which are solution to diffusion (Laplace Poisson) problems, are com-
monly visualized using surfaces of constant scalar value and field lines of the gradient
of the scalar, or its conjugated flux. Vector fields, solution to Lapalce Poisson and