膽管支架(Biliary Stent)為一種中空管狀結構的醫療器材，在近幾年被廣泛應用在因惡性腫瘤或其他原因所造成的阻塞性黃疸。膽管支架放置術是一種侵入性較小的治療方法，可以經由微創支架植入手術撐開已阻塞的膽管，使膽汁流通，並提高癌症病患的存活時間及生活品質。
本研究使用光纖雷射進行加工，以鎳鈦合金管材為基材，利用焦距、功率、脈衝重複頻率等參數進行測試，並找出適合加工之條件進行膽管支架切割加工。並由小管徑的鎳鈦圓管進行切割製作，再擴張至目標直徑。本研究以不同的熱處理時間以及擴張量進行回縮量探討，透過分段擴張的方式成功將不同設計的支架擴張至目標尺寸。此外，本研究將市售的支架輸送系統改良，並將自製的膽管支架壓縮至9F導管中，探討不同設計支架在回收時結構順應性之變化，得知透過改變支架之間距及覆膜可有效改善其順應性。

Biliary stent is a medical device which is a plastic or metal tube that is developed from cardiovascular stents. Recently the different types of biliary stent are widely used to provide a longer patency. The surgery puts thin catheter stent in the bile duct obstruction site, then the stent expands by itself and allow the bile flow through the blockage of the bile ducts, so the patient's symptoms can be alleviated.
In this study, fiber laser was determined to cut nitinol (Ni-Ti) alloy. Optimal parameters were found by investigating focal position, average power, and pulse repetition rate for fabricating biliary stent. This study succeeded to expand different kinds of stent to target diameter and investigated the stent retraction by different heat treatment time and expanded diameter. In addition, a commercial 9F delivery system was modified and the fabricated biliary stents were crimped into the catheter to investigate the flexibility of different type of stent during retrieving into the catheter. Base on the result, adjusting space between strut layers and covering stent with membrane could improve stents’ flexibility effectively.

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