Tumor Growth Simulation
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Such that, DW M, DGM, and DCSF are diffusion coefficients for White
Matter (WM), Gray Matter (GM) and Cerebrospinal fluid (CSF) respectively.
Different values have been assigned to these for both High-Grade Glioma
(HGG) and Low Grade Glioma (LGG); however, the most preferred values in
normalized scale are 1, 0.2, and 0 for DW M, DGM, and DCSF respectively
where this will keep five-fold difference between the WM and the GM. In this
way, the diffusion coefficients for white matter (WM), gray matter (GM), and
cerebrospinal fluid (CSF) are, respectively, DWM, DGM, and DCSF. Both
High Grade Glioma (HGG) and Low-Grade Glioma (LGG) have been given
different values for these; however, the most favored values in a normalized
scale are 1, 0.2, and 0 for DWM, DGM, and DCSF, respectively, where this will
maintain a five-fold difference between the WM and the GM. The weighted
diffusion tensor W(x) has represented using different models such as:
Model 1 (M1) [12, 13, 23]:
W (x) = I =
1
0
0
0
1
0
0
0
1
(5.15)
Model 2 (M2) [18, 22]:
W (x) =
λ1
0
0
0
λ2
0
0
0
λ3
x ϵ WM
I
x ϵ GM
(5.16)
Model 3 (M3) [21]:
W(x) = E
1 + γ(x)(λ −1)
0
0
0
1
0
0
0
1
ET
(5.17)
Model 4 (M4) [10]:
W(x) = E
rλ1
0
0
0
λ2
0
0
0
λ3
ET
(5.18)
Model 5 (M5) [10]:
W(x)=E
λ1(rCl + rCp + Cs)
0
0
0
λ2(Cl + rCp + Cs)
0
0
0
λ3(Cl + Cp + Cs)
ET
(5.19)