內漏 (Endoleak) 可視為腹主動脈瘤腔內修復術 (EVAR) 失敗與否的一項指標，內漏的產生及惡化將提升致死率與併發症發生的危機，若能有效控制內漏的發生，可降低手術再次執行的必要性。本研究目的為運用計算流體力學解析五個植入商用化套膜支架後之病人腹主動脈瘤模型受血液作用產生的應力受力分佈與流場變化，並進一步說明其結果與內漏的關聯，並以流固耦合的數值模擬方式結合血液動力學分析探討了病人特徵模型之壁面應力、壁面剪應力、流場變化與內漏之間的關聯。結果顯示在病人特徵模型中的高壁面應力區 (0.18 – 1.87 MPa) 與內漏發生的位置具有高度相關性，進一步觀察模型內部流場變化發現在血液流速增快的情況下，壁面剪應力也會隨之增大，且其分佈集中於模型中的髂動脈部位，而在模型中主動脈部位靠近支架結構分歧點的區塊為渦流發生區，但不一定為內漏發生區。本研究提供了對於植入商用化套膜支架後之病人腹主動脈瘤一種結構上與流場上的探討與分析，透過本研究的發現希望在未來對於內漏診斷與支架改善有進一步的貢獻。

The aim of this study is to identify the hemodynamic of patient-specific abdominal aortic aneurysm (AAA) with stent-graft by using the fluid-structure-interaction (FSI) method. Endoleaks are severe complications after Endovascular Aneurysm Repair (EVAR) and may induce surgical failure. Therefore, early detection of endoleaks is necessary. In this study, the result was validated using the numerical method to analyze the stress distribution and flow pattern in patient-specific AAA model and identify the relationship between hemodynamic force and endoleak formation.
The relationship between the wall stress distribution and the location of endoleaks was identified by assessing the hemodynamic of patient-specific AAA models. It was found that endoleak locations were well matched to the local peak locations of wall stress (0.18 – 1.87 MPa) in the aneurysm of these patients. Further investigation on the flow field found that higher blood velocity causes higher wall shear stress. The local peak locations of wall shear stress areas were found at the distal legs for all cases in this study. The proximal body close to the distal legs exist the vortex but there is no direct evidence about finding these endoleaks. This study provides the structural and flow analysis of the patient-specific AAA with stent-graft implanted, and may help the treatment in clinical and improvement of stent-graft in the future.

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