患者在進行血液透析前須先建立血液透析管路，其中以透過手術將自身動脈與靜脈進行吻合的自體動靜脈廔管(Arteriovenous Fistula, AVF)方式最為常用。目前市售之動靜脈廔管支架皆為金屬支架，雖然金屬支架置入得以解決廔管急性阻塞的問題，但容易造成後續血栓形成及血管再狹窄的情況發生，如嚴重時常需要進行二次手術。
有鑑於此，本研究以3D列印製作聚乙烯醇(Polyvinyl Alcohol, PVA)快速降解支架，利用覆膜製程(Dip Coating Process)方式將聚己內酯(Polycaprolactone, PCL)溶液浸塗在PVA支架上，並經水解後製作出具生物可降解特性的PCL薄膜型支架模具，再將由PCL多元醇改質之光固化材料PCL-TA(Polycaprolactone-triacrylate)充填至支架模具中，完成動靜脈廔管充填式薄膜型支架，藉由開發生物可降解動靜脈廔管支架，解決目前金屬支架置入後續遇到的問題，避免二次手術的發生。
本研究參考Mirage支架之設計概念，利用調控列印路徑及列印參數進行3D列印支架之製作，並將支架浸泡於去離子水中進行支架後處理，成功製作出具有良好表面品質之PVA快速降解支架。透過將所製作之PVA支架結合覆膜製程，藉由調控溶液濃度、抽取時間及浸塗次數等覆膜參數，得出以溶液濃度9%、抽取時間10秒及浸塗次數2次時，可以製作出具有良好薄膜品質且兼具柔順性之充填式薄膜型支架模具，並得以將由PCL多元醇改質之光固化材料PCL-TA成功充填至支架流道中，製作出一款得以壓縮至9Fr (3mm)之導管，且能夠將動靜脈廔管擴張至6 mm的生物可降解充填式薄膜型支架。最後，以有限元素分析對支架進行徑向力及抗壓力模擬，並以實驗驗證對支架性能進行探討，實驗結果顯示，當支架由6.6 mm壓縮至6 mm，支架徑向力值為0.0712 N/mm，足以提供當動靜脈廔管阻塞時擴張至6 mm之所需，並經由抗壓力測試模擬值與實驗值的比較結果，驗證了有限元素模型能夠成功預測支架受力與形變情形，證明本研究所製作之AVF充填式薄膜型支架之可行性。

Before performing hemodialysis treatment, patients should establish reliable vascular access. Among all types of long-term vascular access, arteriovenous fistula(AVF), to engage patients’ autologous artery and vein by fistula surgery, is the most common type to use. Nowadays, all the arteriovenous fistula stents on the market are made of metal material. Using bare-metal stent(BMS) can solve the acute vascular obstruction, but may cause subsequent thrombosis and vascular restenosis. In some severe cases, performing secondary surgery is needed.
To solve these problems, the study will use 3D printing technology to make polyvinyl alcohol(PVA) rapidly degradable stent, and the dip-coating process will be used to coating polycaprolactone(PCL) film on the PVA stent. In the following, the PVA stent will be hydrolyzed, and then a biodegradable PCL thin-film mold is produced. At last, filling the light-curable material PCL-TA(polycaprolactone-triacrylate), which is modified by PCL triol, into the stent mold to complete the arteriovenous fistula thin film type stent. Developing biodegradable arteriovenous fistula stent can solve the current problems in BMS and prevent performing secondary surgery.
Referring to the design conception of Mirage bioresorbable micro-fiber scaffold, in this study a PVA stent was made by controlling the printing path and printing parameters. Therefore, it is soaked in deionized water to proceed the post-process to produce a PVA rapid degradation stent with good surface quality. After finishing the PVA stent, the stent was dipped in PCL solution by adjusting the coating parameters to achieve the thin-film type mold with good quality and flexibility, and the result shows that the optimized parameters are the solution concentration 9%, the withdrawal time 10 seconds and with 2 times dip coating. Due to the adequate film thickness and good flexibility, the thin film type mold was successful to fill in the light-curable material PCL-TA, and also proved that it can be crimped into a diameter 3 mm(9 French) implantation catheter and expanded to a diameter of 6 mm. Finally, with the ANSYS finite element analysis and prototype testing, when the stent compress from 6.6mm to 6mm and facilitate the arteriovenous fistula expanding to 6mm, the results show that the fabricated AVF stent can reach the requirement of radial force, 0.0712 N/mm, and verify that the finite element model can successfully predict the stress and deformation of the stent, and prove the feasibility of the design and fabrication of AVF thin film stent.

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