Model of Hyperthermia Therapy in Melanoma Treatment: Comparison between Constant and Temperature Dependent Blood Perfusion Rate

This work deals with the modeling of hyperthermia therapy for melanoma skin cancer by considering 3D nonlinear Pennesbioheat transfer equation with Temperature Dependent Blood Perfusion Rate (TDBPR). The proposed model consists of a five-layer biological skin medium with third stage melanoma tumor utilizing each layer by Pennesbioheat equation. A Finite Element Analysis (FEA) in bioheat transfer model is employed and the result of nonlinear model in the time domains is solved using COMSOL Multiphysics. The variables of heat fluxes as control variables were applied to the proposed model for verification and assessing its applicability and effectiveness. The simulation output shows that the proposed model is valid under our test variable. This proposed model is used to easily and accurately study the thermal behavior of the biological skin during hyperthermia treatment procedure

Algoritmo de controle do dano ao tecido saudável no tratamento de câncer por hipertermia

According to the World Health Organization, cancer is a global health concern. The high mortality rate drives the scientific community to study new treatments, among which we can mention hyperthermia by magnetic nanoparticles. This treatment involves subjecting the target region to a low-frequency magnetic field, causing the nanoparticles to increase the temperature above 43◦C, considered the target temperature to damage the tissue and induce cell necrosis. This work uses the three-dimensional in silico model of Pennes, described by a partial differential equation (PDE), to estimate the percentage of tissue damage due to hyperthermia treatment. Differential evolution is used to optimize the treatment, suggesting the best locations for injecting magnetic nanoparticles to maximize the damage to tumor cells and minimize harm to healthy tissue. Tests were performed considering two- and three-dimensional domains, and for each one, three scenarios were considered to evaluate the suggestions obtained by the optimization method. The results indicate that the proposed technique is promising: a reduction in the percentage of damage to healthy tissue while keeping the complete damage to the tumor tissue were observed. Considering the three-dimensional domain in its most complex scenario, the optimization process was responsible for reducing the damage to healthy tissue by 59% when the nanoparticle injections are positioned in a non-intuitive location, i.e., different from the center of the tumors. The numerical solution of the PDE combined with differential evolution increases the computational effort required for algorithm execution. Due to this factor, a parallel strategy using CUDA architecture was implemented to solve the PDE at a lower cost using NVIDIA GPUs. Comparing the parallel version of the code with its sequential version executed in a single CPU, an 84.4-fold performance gain was observed.De acordo com Organização Mundial da Saúde, o câncer é uma preocupação de saúde global. O alto índice de mortalidade move a comunidade científica a estudar novos tratamentos, dentre esses podemos citar a hipertermia por nanopartículas magnéticas. Este tratamento consiste em submeter a região alvo à um campo magnético de baixa frequência, fazendo com que as nanopartículas causem o aumento da temperatura acima de 43◦C, considerada a temperatura alvo para lesionar o tecido e conduzir as células a necrose. Este trabalho usa o modelo tridimensional in silico de Pennes descrito por uma equação diferencial parcial (EDP) para estimar a porcentagem de dano ao tecido devido ao tratamento com hipertermia. A evolução diferencial é usada para otimizar o tratamento, sugerindo os melhores lugares para realizar as injeções de nanopartículas magnéticas de modo a maximizar a lesão nas células tumorais e minimizar os danos ao tecido saudável. Foram realizados testes considerando domínios bidimensionais e tridimensionais e, para cada domínio, três diferentes cenários visando avaliar as sugestões obtidas com o uso do método de otimização. Os resultados indicam que a técnica proposta é promissora: foi observada a redução da porcentagem de dano ao tecido saudável e a completa lesão do tecido tumoral. Considerando o modelo tridimensional em seu cenário mais complexo, o processo de otimização foi responsável por diminuir o dano ao tecido saudável em 59% se as injeções de nanopartículas forem posicionadas em um local não intuitivo, ou seja, diferente do centro dos tumores. A solução numérica da EDP em conjunto com a evolução diferencial aumenta o esforço computacional para a execução do algoritmo. Devido a esse fator, uma estratégia paralela utilizando a arquitetura CUDA foi implementada com o intuito de tornar a resolução da EDP menos custosa, utilizando as GPUs NVIDIA. Comparando o código paralelo com o sequencial executado somente em CPU, observou-se um ganho de desempenho de até 84, 4 vezes

Ono: an open platform for social robotics

In recent times, the focal point of research in robotics has shifted from industrial ro- bots toward robots that interact with humans in an intuitive and safe manner. This evolution has resulted in the subfield of social robotics, which pertains to robots that function in a human environment and that can communicate with humans in an int- uitive way, e.g. with facial expressions. Social robots have the potential to impact many different aspects of our lives, but one particularly promising application is the use of robots in therapy, such as the treatment of children with autism. Unfortunately, many of the existing social robots are neither suited for practical use in therapy nor for large scale studies, mainly because they are expensive, one-of-a-kind robots that are hard to modify to suit a specific need. We created Ono, a social robotics platform, to tackle these issues. Ono is composed entirely from off-the-shelf components and cheap materials, and can be built at a local FabLab at the fraction of the cost of other robots. Ono is also entirely open source and the modular design further encourages modification and reuse of parts of the platform

DICOM for EIT

With EIT starting to be used in routine clinical practice [1], it important that the clinically relevant information is portable between hospital data management systems. DICOM formats are widely used clinically and cover many imaging modalities, though not specifically EIT. We describe how existing DICOM specifications, can be repurposed as an interim solution, and basis from which a consensus EIT DICOM ‘Supplement’ (an extension to the standard) can be writte

Estimation of thorax shape for forward modelling in lungs EIT

The thorax models for pre-term babies are developed based on the CT scans from new-borns and their effect on image reconstruction is evaluated in comparison with other available models

Rapid generation of subject-specific thorax forward models

For real-time monitoring of lung function using accurate patient geometry, shape information needs to be acquired and a forward model generated rapidly. This paper shows that warping a cylindrical model to an acquired shape results in meshes of acceptable mesh quality, in terms of stretch and aspect ratio