末期腎臟病患者（End Stage Renal Disease）在進行血液透析前須先建立血液透析管路，而在建立血液透析管路方式中，以透過手術將自體動脈與靜脈進行橋接的自體動靜脈廔管(Arteriovenous Fistula，AVF)為最優先的選項，因其可使用的時間最長，且後續併發症最少。但是動靜脈廔管在前期靜脈成熟化階段常因靜脈直徑及血流量不足，導致廔管成熟化失敗。本研究設計之廔管支架，是應用於橋接手術時直接放置進入靜脈，擴張此靜脈至適當直徑以有效增加血流量，提高前期動靜脈廔管成熟化機率。
本研究先以ANSYS模擬輔助鎂鋁合金AZ31支架的開發，設計出可以壓縮至2 mm (6 French)以下直徑，並可以氣球擴張至外徑5.4 mm的支架，本研究並以模擬及實驗探討支架在壓縮、擴張後的殘留應力大小，與柔順性及支架擴張後彎曲的表現。最後，此款支架利用飛秒雷射切割完成後，並搭配後處理與浸塗製程，製作出具高分子塗層的AZ31支架。此塗層支架得以改善鎂鋁合金快速降解的缺點，本研究並以控制塗層厚度達到AVF支架所需的28天以上降解天數目標。

Before Hemodialysis, end stage renal disease (ESRD) patients need to establish a dialysis access channel. In the types of dialysis access surgery, the arteriovenous fistula (AVF) that bridges the autogenous artery and vein is preferred and widely used. AVF is the best choice of the dialysis access because it generally lasts longer and has fewer problems. However, venous maturation is a critical issue about AVF use, due to insufficient vein diameter and blood flow. Therefore, a special magnesium alloy stent which can be implanted directly into the vein during the AVF operation is designed in this study. The vessel diameter and blood flow rate could be increased significantly, and improve the maturation rate of the AVF operation.
In this study ANSYS simulation is used to assist the development of magnesium alloy AZ31 stents, and design a stent prototype that can be compressed to an outer diameter of 2mm (6 French) and expanded to 5.4mm. The study also discusses the residual stress of the stent after compression and expansion, and the flexibility and bending performance of the stent after expansion, theoretically and experimentally. Finally, femtosecond laser cutting, combined with post-processing and dip-coating, are used to fabricate the AZ31 alloy stent and the stent’s polymeric coating, which can improve the rapid degradation shortcomings of magnesium-aluminum alloy. To reach the stent requirement for assisting AVF maturation, the degradation tests are performed more than 28 days for deciding the stent’s coating material and thickness.

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