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Abstract-Due to the restriction of the number of probes that a patient can tolerate and the inaccurate information provided by the invasive temperature measurements, which provide information only at discrete points, a mathematical model simulation is more effective to help physicians in planning their thermal treatment doses. This simulation will maximize therapeutic effects while minimizing side effects. Prior to the treatment, it will provide a precise idea of the predicted reaction depending on selected doses; so new treatment strategies can be proposed and evaluated.To simulate cerebral circulation [1], we divide the fluid and matter constituents within the human head into several interacting subunits, so called compartments. Four main characteristics of the analyses of the brain model are fluid dynamics analysis, mechanical analysis, laser beam and heat transfer.The objective of this study is to simulate the Laser Interstitial Thermal Therapy in Treatment (LITT) of brain tumors including all four characteristics described above. The thermal effect of the laser during coagulation lasts around one second and its temperature is between 50 0C and 90 0C. LITT has the following results; the desiccation and retraction of the tissue to destroy tumor phenomena.Index Terms-Laser interstitial thermal therapy, thermal damage, brain cancer, bioheat transfer simulation.

During the laser thermal ablation process, it is challenging to control the side effects and optimize the planning of the dosimetry process for all patients. A software tool would help physicians plan and manage the dosimetry process while predicting and organizing the treatment. This would maximize the therapeutic effect and minimize any side effects, so new strategies can be proposed and evaluated.In this paper, we propose a new dosimetry planning approach for the laser surgery/cancer treatment with physician interaction that takes into account all the steps of the management of the dosimetry process. Depending on the impact of the thermal damage to the tissue during the simulation, the software tool will output a dosimetry schedule for each simulation and keep all choices for a final decision.Using Client Server technology, the software tool will also include a public and shared knowledge database to keep track of all simulations and learning process. This will optimize the process by dropping all unwanted simulation by delimiting the tissue tumor size, probe size, laser power, and time range.A case study of the Laser Interstitial Thermal Therapy (LITT) will demonstrate the feasibility of the dosimetry framework. LITT can be a highly complex treatment, with many parameters influencing treatment efficacy.

The objective of the Laser Interstitial Thermal Therapy (LITT) in treatment is the maximization of the therapeutic effects (tumor tissue laser ablation) with the minimization of any side effects (damage to healthy tissue). The big challenge is the approximation of the tissue tumor topology. While using the MRI stack to capture the 3D tissue tumor topology, a software for conversion to 3d stl file can be used, but the result is always far away from the real topology of the tissue tumor. Mathematical models will help us predict the temperature distribution and tissue damage during the dosimetry planning phase. These models need to be validated with real data in order to be accepted and used by physicians in the dosimetry planning. This paper describes a modeling analysis approach for the prediction of laser ablation volume during the planning phase. Three different COMSOL implementations of thermal damage during the Laser Interstitial Thermal Therapy in Treatment of tissue tumors were proposed and validated with real data to confirm the validity of these models. A prediction damage formulation is generated and implemented as a Field-Programmable Gate Array (FPGA). The final product of these implementations is expected to be used by physician as apps during the planning of the dosimetry. 1

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