Modeling Of Laser Induced Interstitial Thermotherapy Of Laser Tissue Considering Effect Of Fat Melting

Maerefat, Mehdi; Mokhtari Dizaji, Manije; Haddad Soleimani, Zahra

doi:10.22041/ijbme.2009.13381

Modeling Of Laser Induced Interstitial Thermotherapy Of Laser Tissue Considering Effect Of Fat Melting

Document Type : Full Research Paper

Authors

Mehdi Maerefat ¹

Manije Mokhtari Dizaji ²

Zahra Haddad Soleimani ³

¹ Associated Professor, Mechanical Engineering Group, Engineering School, Tarbiat Modares University

² Professor, Medical Physics Group, Medical Sciences School, Tarbiat Modares University

³ M.Sc. Graduated, Mechanical Engineering Group, Engineering School, Tarbiat Modares University

https://doi.org/10.22041/ijbme.2009.13381

Abstract

In this paper a comprehensive mathematical model for thermal analysis of liver tissue in thermotherapy of liver cancer by laser is presented. In the present model the diffusion approximation analytical method for radiative heat transfer modeling of heat transfer process in the tissue is used for the first time. Heat transfer modeling in the biological tissue is carried out using Penes model taking into account the influence of thermal and blood perfusion coefficient fluctuations due to temperature changes as well as the effect of lipid melting on temperature distribution through enthalpy method is taken into account. In the present study the tumor is considered as a sphere with thermo-physical properties different with those of healthy tissue. Finally, the obtained non-linear equations are solved using the numerical finite volume method. Temperature distribution at several instants during the thermotherapy is calculated. The comparison of the calculated results with those of experimental results indicate a good agreement between the results. Furthermore, the effects of different parameters such as laser specifications and optic coefficient changes (through proper photopherin injection) on laser-affected area are studied using the present analytical method. These results can help the specialists in order to come upon a safe LITT method for destruction of cancerous tissues without harming the healthy ones.

Keywords

Thermal Therapy

Diffusion Approximation

Laser

Heat Transfer

Pennes Model

Enthalpy Method

Subjects

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