腦部取栓支架(stent retriever)是用來治療腦部血管栓塞的醫療器材，可透過微創手術以微導管輸送至栓塞部位並將血栓取出。一般市售取栓支架多以鎳鈦支架為主，藉其形狀記憶特性使支架在人體溫度下得以自擴張，但鎳鈦支架具有加工程序繁複、材料及加工成本較高且難以客制化等問題。

本研究以開發高分子取栓支架為目標。支架高分子材料選用TPC(Thermoplastic copolyester)，因其具有出色的回彈性、可恢復性及生物相容性，且適合以3D列印製程進行支架製作。利用電腦數值模擬分析與3D列印製程開發製作TPC取栓支架，並探討不同機械特性的血栓對支架取栓性能的影響。

以實驗探討三款TPC支架(支架外徑及結構寬度均為4mm及0.2mm，三款支架結構厚度分別為0.2、0.4、0.6mm)壓縮至微導管內釋放時的徑向力，與模擬所得切穿血栓所需的徑向力進行比較，藉此評估不同支架設計其取栓性能的表現。藉由血栓模擬物的製作及體外取栓系統的建構，驗證所開發製作支架的取栓性能。透過調製不同硬度的洋菜凍模擬血栓之機械特性，並利用體外取栓系統進行實驗驗證。實驗驗證結果與模擬結果相符，並成功驗證高分子取栓支架之可行性。

The stent retriever is a medical device used to treat cerebral vascular embolism. Currently, most of the stent retrievers are nitinol stents. By virtue of its shape memory property, the stent can self-expand at human body temperature to provide sufficient radial force to penetrate and capture the thrombus and then retract it into the catheter, but nitinol stents have many problems such as complicated processing procedures, high material and processing costs and difficult to be customized.

The purpose of this study is to develop a polymer stent retriever. TPC (Thermoplastic copolyester) was selected as the polymer stent material because of its excellent resilience, restorability and biocompatibility, and suitable for 3D printing process. In this study, computer numerical simulation analysis and 3D printing process were used to develop and fabricate the TPC stent retriever, and discuss the effects of different mechanical characteristics of thrombus on the stent clot-capturing abilities.

In this study, we discussed the radial force of three TPC stent retrievers (the thickness of the three stents are 0.2, 0.4, and 0.6mm respectively) and compared with the radial force required to penetrate the thrombus by the simulation to evaluate the stent clot-capturing abilities with different stent designs. This study about clot-capturing abilities of the stent was verified by preparing embolus analogues and setting up an in-vitro thrombectomy system. Agar jelly of different hardness were used to simulate the mechanical properties of thrombus with the thrombectomy system for experimental verification. The experimental results are consistent with the simulation results and the feasibility of polymer stent retriever is verified successfully.

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