血管腔內主動脈瘤修復(endovascular aneurysm repair, EVAR)，已被廣泛使用於治療主動脈瘤症狀。然而目前市售鎳鈦金屬支架仍然存在血液內漏與支架位移等問題，使支架置入後仍有16%患者需進行二次手術[1]，且考量到金屬支架長期在體內可能發生的併發症，目前臨床上不建議以支架置入來治療較早期的主動脈瘤(直徑較小的主動脈瘤)[2]。本研究將以真實患者主動脈瘤的模型建模，利用3D列印結合可高度客製化製造的優勢，設計出一款針對本案例主動脈瘤形貌的三維結構客製化高分子支架，並透過有限元素軟體模擬修正，增強支架與血管的接觸壓力與主動脈在近端口的密封性，有效的防止支架位移與血液內漏的發生。另外，本研究將採用可降解的高分子材質，提出對於早期的主動脈瘤患者一種治療方法。最後，本研究以仿真主動脈瘤模型實際測試，並提出個人化治療主動脈瘤支架的設計、製造與測試流程。

The aorta is the body's largest blood vessel, which carries blood from the heart to the chest and trunk. The aortic aneurysm is a spheroid enlargement of the aorta. The aortic aneurysm could be stripped or ruptured. It also endangers the life of the patient. At present, repairing surgery using aortic aneurysm stents (AA stents) is a widely used treatment for severe aortic aneurysms. However, about 16% of patients have stent migration or endoleak due to the inability of the stent to effectively adhere to the blood vessel wall after the operation and require a second operation for treatment. In addition, considering the risk of long-term retention of metal stents in the body, it is not recommended to use AA stents in patients with early (smaller diameter) or benign aortic aneurysms currently.
In this study, we build a 3D aortic aneurysm and vascular model based on the computed tomographic images (CT images) of patients with aortic aneurysm and design a new three-dimensional AA stent that can completely fit the wall of the aortic aneurysm and vascular around it. The parameters of the stent structure are computationally adjusted by using the finite element method to get a larger contact pressure and proximal sealing between the stent and vascular that can effectively prevent the stent migration and endoleak. This research applies 3D printing technology that can be fully customized and rapidly manufacture the designed AA stent and use degradable polymer materials to make new types of AA stents for the early and benign aortic aneurysm patients who cannot be treated by the current stent. Finally, the new AA stent designed and produced in this study will be placed and tested on a simulated aortic aneurysm platform to verify whether it can achieve the expected function. This simulated aortic aneurysm platform includes a circulatory system that mimics the blood flow of the human body and a transparent aortic aneurysm polymeric model designed and made according to the patient's CT images.

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