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Simulation of electroporation process in stent oclussion therapy
Hemzal, Martin ; Cipín, Radoslav (referee) ; Novotná, Veronika (advisor)
This masteral thesis describes phenomenon of electroporation and it’s use to deal with occluded self-expandable metalic stent. Thesis briefly summarizes theory of electroporation, currently used medical treatments of occluded stents. The next part of the thesis is dedicated to current state of mathematical simulations of electroporation. The core of the thesis are simulations of electroporation effects on tissue of occluded metal stents.
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High Voltage Pulse Generator for Electroporation of Cells
Puczok, Václav ; Martiš, Jan (referee) ; Červinka, Dalibor (advisor)
The main goal of this thesis is to design control board for the experimental electroporation device and to develop control firmware. The first chapter of this work focuses on the electroporation phenomenon itself. Behaviour of the cell model in external electrical field is described there as well as simulation and overview of how electroporation affects living tissue. It also explains the main requirements for parameters of the electroporation pulses as well as need for ECG synchronization. Furthermore, some remarks are given about novel high frequency electroporation method, which involves use of nanosecond bipolar high voltage pulse bursts. The second chapter briefly introduces commercial electroporation device called Nanoknife, including control part, power part, and it's limits. The third chapter consists of introduction of the novel experimental electroporation device developed at BUT. Power part of this device is discussed as well. Next chapter focuses on design of the control board for this device and also on description of the particular schematic parts. There is a control algorithm explanation in the fifth chapter of this thesis followed by the brief manual to machine operation.
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Modeling of the thermal effects on living tissue during electroporation process
Kafka, Roman ; Cipín, Radoslav (referee) ; Červinka, Dalibor (advisor)
The work deals with the current state of knowledge of heat transfer in living tissue. It is described here what the distribution of heat is affected with and the existing calculation options. For solving Pennes equation using finite element method COMSOL Multiphysics 5.4 is used. From the current state of the published studies, three are selected and described, each using a different approach. Based on the benefit of each of the studies described, a simple model of its own that simulates an ablation catheter attached to cardiac tissue is solved. A change in electrical conductivity as a function of the electric field intensity is taken into account, but there is also a comparison with anisotropic tissue that has electrical conductivity in different directions. The result of the calculation is voltage distribution, density of electric current and losses, temperature distribution in the model at several time points and graph of temperature development over time.
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EKG synchonization of electroporation pulses
Nohel, Michal ; Mézl, Martin (referee) ; Novotná, Veronika (advisor)
Bachelor thesis is focused on cells electroporation principle and its types. It further describes thermal and nonthermal ablation techniques with an emphasis on irreversible electroporation. It contains an overview of fields, where medical procedures in combination with ECG signal are used, and an overview of techniques and measurements of the electrocardiographic signal. Further, the sensitivity of the human body to electroporation pulses is discussed. During electroporation, short high-voltage pulses are applied. Ventricular fibrillation may occur if the electroporation pulse is applied to the vulnerable period of the heart rhythm. Synchronization of pulse application with heart activity of the patient is necessary for health and safety reasons in clinical practice. The practical part of the thesis is about a LabVIEW program for this kind of synchronization. The created program is tested and the obtained results achieved are evaluated in terms of practical use.
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Simulation of electroporation process in stent oclussion therapy
Hemzal, Martin ; Cipín, Radoslav (referee) ; Novotná, Veronika (advisor)
This masteral thesis describes phenomenon of electroporation and it’s use to deal with occluded self-expandable metalic stent. Thesis briefly summarizes theory of electroporation, currently used medical treatments of occluded stents. The next part of the thesis is dedicated to current state of mathematical simulations of electroporation. The core of the thesis are simulations of electroporation effects on tissue of occluded metal stents.
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Experimental Use Of Novel Pulse Generator For Irreversible Electroporation
Novotná, Veronika
Irreversible electroporation (IRE) is a relatively new technique for minimal invasive nonthermal ablation treatment of solid tumors. This article describes basics of IRE and available devices for this technique. The parameters of commercial NanoKnife IRE generator are verified and the unique experimental IRE generator developed at the Brno University of Technology is presented in this paper. Further, there is a comparison of thermal effects on a target tissue of commonly used radiofrequency ablation (RFA) and the novel IRE generator using an infrared camera. All experiments were performed ex vivo on a porcine liver. The difference in maximum temperature between the output powers used was 17.8 °C with RFA and 3 °C with IRE. This is a significant difference and shows the IRE’s capability of liver tissue ablation without thermal damage. The new IRE generator is also capable of replacing NanoKnife because of its features and versatility.
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Modeling of the thermal effects on living tissue during electroporation process
Kafka, Roman ; Cipín, Radoslav (referee) ; Červinka, Dalibor (advisor)
The work deals with the current state of knowledge of heat transfer in living tissue. It is described here what the distribution of heat is affected with and the existing calculation options. For solving Pennes equation using finite element method COMSOL Multiphysics 5.4 is used. From the current state of the published studies, three are selected and described, each using a different approach. Based on the benefit of each of the studies described, a simple model of its own that simulates an ablation catheter attached to cardiac tissue is solved. A change in electrical conductivity as a function of the electric field intensity is taken into account, but there is also a comparison with anisotropic tissue that has electrical conductivity in different directions. The result of the calculation is voltage distribution, density of electric current and losses, temperature distribution in the model at several time points and graph of temperature development over time.
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