This document summarizes a study that used computer modeling to simulate the electric field and temperature increase in breast tumor and healthy tissue during electroporation. The study applied electric fields from steel electrodes to a simulated breast containing a spherical tumor. It modeled the electric potential, current density, and temperature distribution in the tissues. The results showed lower electric potential within the tumor but higher current distribution in healthy tissue. The study concluded electroporation increased temperature due to current distribution and electrodes should avoid touching healthy tissue to prevent unnecessary effects.
Modeling of Electric Field and Joule Heating inBreast Tumor during Electroporation
1. “Modeling of Electric Field and Joule Heating in
Breast Tumor during Electroporation”
Departamento de Ingeniería Eléctrica, CINVESTAV
Sección Bioelectrónica.
CONACYT Instituto Nacional de Rehabilitación Subdivisión de Investigación
Biotegnológica
Instituto de Enfermedades de la Mama- FUCAM, Mexico City, Mexico.
2016 13th International Conference on Electrical Engineering, Computing Science and
Automatic Control (CCE), Mexico, City. Mexico. September 26-30, 2016.
C. A. Ramírez Martínez*, A. L. Vera Tizatl, C. E. Vera Tizatl, P. R. Hernández Rodríguez, A. Vera
Hernández, L. Leija Salas, M. I. Gutiérrez Velasco, S. A. Rodríguez Cuevas
2. • Introduction
• Methodology
• Results
• Conclusion
2016 13th International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE), Mexico, City. Mexico. September 26-30, 2016.
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Contents
3. • In this work, it is presented a simulation of a breast carcinoma
embedded in healthy tissue under an electric field exposure through
steel electrodes.
• These work seeks to observe the current density and the
temperature rise in both tissues.
Introduction
4. 𝛁 𝛔 + 𝛆
𝛛
𝛛𝐭
𝛁𝚿(𝐱, 𝐲, 𝐳, 𝐭) = 𝟎 (𝟏)
Fig. 1. Exposure of a spherical cell with
radius R, thickness membrane d within an
electric field.
∆𝚿 𝐦 = 𝛂𝐄𝐑𝐜𝐨𝐬𝛉 (𝟐)
𝛂 =
𝟑𝛔 𝐞 𝟑𝐝𝐑 𝟐
𝛔𝐢 + (𝟑𝐝 𝟐
𝐑 − 𝐝 𝟑
) 𝛔 𝐦 − 𝛔𝐢
𝟐𝐑 𝟑 𝛔 𝐦 + 𝟐𝛔 𝐞 𝛔 𝐦 +
𝟏
𝟐
𝛔𝐢 − 𝟐 𝐑 − 𝐝 𝟑(𝛔 𝐞−𝛔 𝐦)(𝛔𝐢−𝛔 𝐦)
(𝟑)
The spatial and temporal distribution of the electrical potential in a medium, is given by Eq. 1 [Tizatl, A.L.V., et al. 3D model and
simulation of electroporation application on healthy and tumoral breast tissue. in Electrical Engineering, Computing Science and
Automatic Control (CCE), 2013 10th International Conference on. 2013..].
Methodology
2016 13th International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE), Mexico, City. Mexico. September 26-30, 2016.
4
5. 𝒒
~
==
𝑬 𝟐
𝑳 𝟐
𝝈
𝝈 𝟎 𝑽𝒂 𝟐
(𝟕)
𝜵 𝟐
𝑻 − 𝒘 𝒃
𝒄𝑳 𝟐
𝒌
𝑻 + 𝒒
~
=
𝜹𝑻
𝜹𝒕
(𝟖)
2016 13th International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE), Mexico, City. Mexico. September 26-30, 2016.
5
Figure 2. A tumor tissue of 1 cm in diameter (1), inside
healthy tissue of 8 cm diameter is proposed (2). Two
stainless steel electrodes 1.2 mm diameter (3).
The joule heating energy term is given by Eq. 7 [Van Gemert, M.J., et al., Irreversible electroporation: just another form of thermal therapy? Prostate, 2015.
75(3): p. 332-5.]. The heat transfer in tissue is given by Eq. 8 [Becker, S.M. and A.V. Kuznetsov, Thermal damage reduction associated with in vivo skin
electroporation: A numerical investigation justifying aggressive pre-cooling. International Journal of Heat and Mass Transfer, 2007. 50(1-2): p. 105-116.]
Material
Health
tissue
Tumoral
tissue
Units
Electrical
conductivity
0.5 0.03 S/m
Relative
permittivity
123 80 1
Thermal
conductivity
0.49 0.5 W/(m*K)
Density 1090 1000 kg/m^3
Heat capacity 3421 4000 J/(kg*K)
Table 1 Material proprieties in adiabatic form [2].
1 2
3
The initial conditions to the phenomena were in
37-celsius degrees and the boundaries of the
health tissue are in 25-celcius degrees.
6. MESHING GEOMETRY
6
Figure 3. The solver used was adjusted to display the electric field distribution applied by the boundary electrodes
inside the both kinds of tissue .
,
2016 13th International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE), Mexico, City. Mexico. September 26-30, 2016.
7. Results
7
Figure 4. Electrical Potential thought tumoral tissue. Figure 5 . Electric field distribution and current
density in breast tissue.
,
2016 13th International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE), Mexico, City. Mexico. September 26-30, 2016.
8. 8
Figure 7. Isothermal distribution of electric field.
,
2016 13th International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE), Mexico, City. Mexico. September 26-30, 2016.
9. Conclusions
• The electroporation caused by potential induced by the electrodes, increase in
temperature due to the distribution of current.
• The distribution of electric potential inside the tissues was lower within the tumor
tissue compared to healthy tissue.
• The current distribution through the tissues was higher in the tissue healthy that in
tumor tissue.
• We must pay attention to prevent the electrodes from touching the healthy tissue at
least possible because the electroporation is not needed in this area, neither the
current distribution in this tissue.
9
,
2016 13th International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE), Mexico, City. Mexico. September 26-30, 2016.
Editor's Notes
Saluda
GOOD MORNING
Presenta
Buenas tardes mi nombre es carlos ramires y vengo a presentarles el trabajo enviado al CCE titulado Simulacion de la distribucion del cmapo electrico y el efecto del calentamiento de Joule en tumor de mama.
van de 100 a 1m Se desprecia la dependencia temporal
Al ser el fenómeno pulsante de campo eléctrico dentro del rango de 100us a 1ms y comando en cuenta que la carga de la membrana celular al esta comportarce como un capacitor, es del orden de 1us, se desprecia la parte temporal y solo queda la parte espacial con respecto a la conductividad
Existe una relación directamente entre la permeablilidad y la conductividad
Cito transformación de coordenandas de cartecianas a esféricasGeometria asimotal debido a la orientación del campo eléctrico
Quedando solo con la dependencia de dos variables.
van de 100 a 1m Se desprecia la dependencia temporal
Al ser el fenómeno pulsante de campo eléctrico dentro del rango de 100us a 1ms y comando en cuenta que la carga de la membrana celular al esta comportarce como un capacitor, es del orden de 1us, se desprecia la parte temporal y solo queda la parte espacial con respecto a la conductividad
Existe una relación directamente entre la permeablilidad y la conductividad
Cito transformación de coordenandas de cartecianas a esféricasGeometria asimotal debido a la orientación del campo eléctrico
Quedando solo con la dependencia de dos variables.