缺血性中風常見的原因是腦血管堵塞導致腦部缺氧，現在已逐漸開始使用機械取栓術進行缺血性中風的治療。但機械取栓裝置在臨床使用上還有許多問題，例如以取栓裝置取栓易導致血管壁損傷、取栓過程易造成血栓破裂而導致遠端血管栓塞、對於老化或鈣化血栓的取栓結果較差等。
因此，本研究嘗試開發新型的聚合物支架取栓系統以改善目前取栓手術在臨床上會遇到的困境，並建立一系列的體外取栓模型進行驗證。聚合物支架的幾何結構為參考市售取栓支架的設計概念進行設計，並規畫列印路徑及調控列印參數進行所設計聚合物支架的3D列印製作。支架材料使用熱塑性共聚酯 (Thermoplastic Copolyester, TPC)，而非市售取栓支架常用的鎳鈦合金，藉由使用更柔順的支架材料來改善支架取栓可能導致血管壁損傷的問題。另外，本研究嘗試以旋轉取栓，及搭配氣球導管使用的吸出裝置，探討解決鈣化血栓的取栓結果較差及血栓破裂而導致遠端血管栓塞等現行取栓技術需克服的問題。
本研究建立了模擬血管內取栓的體外支架取栓驗證模型，並製作了鈣化血栓模擬物用於此驗證模型。藉由所建立的體外取栓模型及鈣化血栓模擬物，本研究初步驗證所開發的新型聚合物支架取栓系統應可成功解決現行機械取栓術需克服的問題。

The common cause of ischemic stroke is a blockage of blood vessels that leads to a lack of oxygen in the brain, and using mechanical thrombectomy is gradually being used for the treatment of ischemic stroke. However, there are still many problems in the clinical practice of mechanical thrombectomy devices. For example, thrombectomy with stent retrievers can easily lead to vascular wall injury, thrombosis rupture leading to distal vascular embolism, and poor thrombectomy results for aging or calcified thrombosis.
Therefore, this study attempted to develop a new polymer stent thrombectomy system to improve the clinical difficulties encountered in the current thrombectomy and established a series of in vitro thrombectomy models for verification. The geometric structure of the polymer stent was designed according to the design concept of commercially available thrombectomy stents, and the printing path and printing parameters were planned to make 3D printing of the designed polymer stent. Using thermoplastic copolyester instead of Nitinol, which is commonly used in commercially available thrombectomy stents, ameliorates the problem of vascular wall damage caused in stent thrombectomy by using a more flexible stent material. In addition, this study attempted to solve the problems that the current thrombectomy technology needs to overcome, such as poor thrombectomy results of calcified thrombus and distal vascular embolism caused by thrombosis rupture, by using rotary thrombectomy and aspiration device with a balloon.
In this study, an in vitro stent thrombectomy validation model simulating intravascular thrombectomy was established, and a calcified thrombus analog was made for this validation model. An established in vitro thrombectomy model and calcified thrombus mimetic demonstrated that the new polymer stent thrombectomy system can successfully solve the problems that the current mechanical thrombectomy needs to overcome.

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