近年來，神經義肢與組織工程為生醫工程的重要領域。環型銬式電極為神經義肢的元件，此電極主要應用於功能性電刺激與神經電位訊號的量測。環型銬式電極植入人體周邊神經所施壓力，有可能導致周邊神經內微管與血管的阻塞，造成神經組織的壞死而失去功能。目前對周邊神經生物力學方面的研究相當有限，因此有需要建立一套生物力學與電學的模型來改善電極的設計與效能。本研究的目的在於周邊神經生物力學與電學分析，由於周邊神經組織為非均質且幾何形狀不規則，因此以有限元素套裝軟體ANSYS進行分析。生物力學分析包括材料特性實驗與模擬，而電學分析則包括肌電訊號對神經電位訊號的干擾與電極的佈置對電刺激空間選擇性的影響。
本研究成果在生物力學分析方面，已完成周邊神經壓縮位移與力量的實驗，並藉以估測周邊神經材料參數的數量級，其楊式係數為41.6kPa。在電學分析方面，當銬式電極全長大於25mm之後，能有效地降低肌電訊號的干擾；並且設計出新的十字型電極佈置能有效地提升傳統侍從向電極的電刺激選擇性，降低橫向電極刺激所需的能量。

Recently, neural prostheses and tissue engineering are important areas in biomedical engineering. In neural prosthesis, spiral cuff electrodes are utilized for functional electrical stimulation and electroneurogram recording. However, the peripheral nerves surrounded by spiral cuff electrodes may be subject to external pressure, which may result in the injury or malfunction of the nerve. Furthermore, the selectivity of FES is an important design factor for spiral cuff electrodes. Therefore, the goal of this thesis is to develop biomechanical and bioelectrical models of peripheral nerves for designing spiral cuff electrodes and for understanding biomechanics of neural tissues. An experimental system was built to measure the mechanical properties and geometric shape of peripheral nerves. It was difficult to study the electric characteristics of peripheral nerves by analytic method, so the finite element method is utilized for analysis and design of electrodes.
From the peripheral nerves testing, biomechanical properties of nerve are estimated. The apparent Young’s modulus of peripheral nerve is 41.6 kPa. For the electrical analyses, the performance of ENG recording may be improved by proper shielding of electromyogram. A novel electrodes may be that can increase the selectivity and decrease the current density is designed based on the bioelectrical analyses.

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