周邊動脈疾病(Peripheral artery disease，PAD)是指發生於非冠狀動脈、非腦部動脈的動脈血管疾病，主要為血管硬化、出血或阻塞，需依據不同嚴重程度給予適當治療。當發生肢體嚴重缺血時，會以經皮血管成形手術，使用氣球擴張或置入金屬支架，以暢通阻塞的血管。目前市售周邊血管支架大多以鎳鈦自膨脹支架為主，然而金屬支架仍有一定的再狹窄率及支架內再阻塞風險，因此使用可降解支架成為置入支架治療周邊動脈疾病的新選項。
本研究以ANSYS輔助，設計出可以壓縮至2 mm (6 French)直徑以置入導管內，並可以氣球擴張至外徑5.4 mm的可降解聚乳酸周邊動脈支架，之後再利用3D列印的方式進行所設計支架製作。藉由調整不同列印參數以製作具有加工裕度的聚乳酸支架，並搭配飛秒雷射進行支架後處理。本研究透過雷射路徑規劃及支撐管圖形預切割的方式，成功以飛秒雷射後處理3D列印的聚乳酸支架，製作出結構寬度均勻、表面形貌平整、結構尺寸符合預期的聚乳酸支架成品。最後，本研究擴張支架至設計尺寸，並且量測支架擴張後抗壓力，實驗結果證明所製作支架可達到0.079 N/mm的設計需求，成功符合周邊動脈支架的要求規格。

Peripheral artery disease (PAD), which is the arterial vascular diseases that occur in non-coronary arteries and non-cerebral arteries, is mainly caused by arteriosclerosis, hemorrhage, or occlusion. The appropriate treatment should be given according to different severity. When severe limb ischemia occurs, a percutaneous angioplasty procedure is usually applied and a balloon dilation catheter or a metal stent is used to expand the vessel. Currently, most of the peripheral vascular stent are nitinol self-expanding stent. However, metal stents still have the problems such as restenosis and the risk of re-occlusion in the stent. Therefore, the use of bio-degradable stents has become a new option as the treatment for peripheral arterial disease.
With the ANSYS finite element analysis, a bio-degradable polylactic acid (PLA) peripheral arterial stent was designed. It can be crimped into a diameter 2 mm (6 French) implantation catheter and expanded to diameter 5.4 mm. The designed stent was then fabricated by 3D- printing. A PLA stent which had prearranged finish allowance was fabricated by adjusting different printing parameter and a femtosecond laser machine was then used to proceed the post-process to achieve the required dimensions and surface quality of stent. In this study, by the method of planning the laser cutting route and pre-cutting the support tube, the final PLA stent was successfully processed by femtosecond laser and the produced stent is with uniform structure width and shape, good surface and edge quality, and good dimension accuracy. Finally, the stent was expanded to the 5.4 mm diameter and the compression force of stent was measured. The result shows that the fabricated stent can reach the designed requirement 0.079 N/mm and meet the requirement of normal peripheral arterial stent.

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