神經義肢與組織工程為近年生醫工程的重要領域。環型銬式電極為神經義肢的重要元件之一，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後所施壓力，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，本研究期望能設計出環型壓縮測試系統，藉此模擬銬型電極環繞於神經上時，施加於周邊神經的壓力。研究的目的在於進行活體的周邊神經生物力學分析與微循環量測，生物力學分析包括材料特性實驗與模擬，模擬部分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，而微循環部分，藉由都卜勒雷射來量測活體於不同壓力下，神經內微血管的血流量變化。
本研究成果在生物力學分析方面，已完成周邊神經壓縮徑向位移與壓力的實驗，並藉以估測周邊神經生物力學參數及範圍，其楊氏係數為59.1-76.3kPa，並推斷出神經纖維束與神經外膜之楊氏係數皆為神經束膜的0.04-0.9倍之間。在微循環方面，完成神經受壓與形變對於血球灌流值之影響，當神經徑向應變大於0.13以及受壓壓力大於23mmHg時，血球灌流值會有明顯降低之情形發生。

Recently, neural prostheses and tissue engineering have become two of the important areas in biomedical engineering. In neural prosthesis, spiral cuff electrodes are mainly 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. It is believed that developing a soft tissue compressor system to simulate the above-mentioned condition is necessary for the realization of neural prostheses. Therefore, the goal of this thesis is to integrate a novel soft tissue compressor and a laser doppler flowmetry to perform the in vivo experiment on anesthetized rabbits to obtain the in vivo biomechanical properties of peripheral nerves. An experimental system was built to measure the mechanical properties. Due to inhomogeneity and complicated geometry of peripheral nerve tissues, it is hard to characterize the mechanical properties of the nerve by analytical approach. Instead of pure analytical method the finite element method is utilized. For studying the microcirculation of the nerve trunk, the nerve trunk was compressed in vivo, and the laser doppler flowmetry was utilized to measure the blood cell perfusion simultaneously.
From the peripheral nerves testing, biomechanical properties of nerve are estimated. The apparent Young’s modulus of peripheral nerve is 59.1-76.3 kPa. Both of nerve fibers and epineurium are 0.04-0.9 times the Young’s modulus of perineurium. For the microcirculation, the effect, of nerve deformation to BPU (blood perfusion unit) was completed. The results indicated that the BPU will be decreased significantly when the radial strain of nerves is greater than 0.13 and the pressure greater than 23mmHg.

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