Thermal Damage Modeling Analysis and Validation during Treatment of Tissue Tumors Mhamed Nour, Aziz Oukaira, Mohammed Bougataya, and Ahmed Lakhssassi Computer Engineering Department, University of Quebec in Outaouais Gatineau, (PQ), 18X 3X7, Canada Email: {noum03, ouka02, bouga01, lakhah01}@uqo.ca Abstract—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 Index Terms—biomedical informatics, computational biology, laser interstitial thermal therapy, laser ablation, dosimetry planning. I. INTRODUCTION With the integration of Laser Interstitial Thermal Therapy (LITT) with MRI (magnetic thermal imaging) in order to produce MRTI (magnetic resonance thermal imaging) which is now a new option for the cancer treatment, many real case studies in the domain of LITT are published in literature. They differ by the type of tissue used, the specification of the laser source, the power used during the treatment and the time of the treatment. In this paper, our approach were compared to the real results and confirm the validity of our results to predict thermal damage and temperature distribution during the treatment of tissue tumors. A valid prediction approach will help improve the health care system and help physicians during the planning phase of the treatment with the objective being the maximization of the therapeutic effects and the minimization of any side effects. Manuscript received June 25, 2017; revised August 23 , 2017. II. LITT AND CASE STUDIES LITT uses light absorption to create a precise minimally, invasive injury to targeted tissue inducing acute coagulation necrosis [1]. The Visualize system and Neuroblate system are using the MRI guided technology. Many real case studies [1-6] in the domain of LITT are published in the literature. They differ by the tissue, the specification of the laser source, the power used during the treatment and the time of the treatment. Let’s briefly describe the treatment used by the case studies. A. Human Brain As stated in (1), they used the Visualize system which consists of 15 W, 6980 nm diode, Led of 1.6 mm diameter, cooling apparatus, and an image-processing workstation. The laser fiber was placed at the center of the lesion in the human brain, then two thermal ablations were performed: 11 watts for 31 second and 10 watts for 30 seconds. Fig. 1 shows the MRI of the brain with the right thalamic enhancing tumor. Figure 1. MRI of the brain that show the right thalamic enhancing tumor. Fig. 2 shows the MRI with damage, as stated in [1] the size of the laser ablation is 2.5 mm by 9.5 mm (23.75 mm2). Some of the case studies provide their results in 2D only because it is difficult to calculate the volume from MRI Stack. With our simulation tools, this sytudy validate the 2D dimensions and provide the third dimension. Figure 2. IMRI with the damage model. International Journal of Pharma Medicine and Biological Sciences Vol. 6, No. 4, October 2017 98 ©2017 Int. J. Pharm. Med. Biol. Sci. doi: 10.18178/ijpmbs.6.4.98-104