The Application Of FEM In Deep Brain Stimulation

Deep brain stimulation technology( DBS) has become an important therapeutic method for the athletic disorders, such as essential tremor, muscle dystonia, Parkinson’s disease, epilepsy, intractable pain and so on, due to its good selectivity, clear targets, micro damage, reversibility and adjustability. In this thesis, DBS system has been simulated by using the finite element simulation software and neuron simulation software. It aims to analyze the influence of the stimulus produced by DBS electrodes on the potential distribution around them and the influence of the voltage stimulus out of the cell membrane on the excitability of neurons.Firstly, a model of the current drive three-electrode has been designed. The inputted drive current could be adjusted by adjusting the parameter of ?. In the finite element software, 2D circular model and 3D spherical model have been constructed. Under the different drive current, potential distribution around the electrodes was calculated and the influence of the stimulation target and the stimulus intensity was compared.Secondly, according to the geometric parameters and the electrical parameters of cranial nerve fibers, the multi-compartment double cable model of cranial nerve has been established with the neuron simulation software NEURON7.3 based on the electrical characteristics of neuron and the H-H model.Finally, neuron model has been established in the finite DBS model. It has been calculated under the different parameter ?. The potential value of the cranial nerve fibers around the electrodes have been extracted and loaded to the multi-compartment double cable model. Through calculation and comparisons in NEURON7.3, the impact of the different drive current values and the different pulse width values on the excitability of neurons was achieved.In this thesis, influence of DBS system on the excitability of neurons has been obtained by combining the macro and micro analysis. The results will provide the theoretical basis for the further research on DBS system and clinical applications.