顱內動脈瘤為一種腦血管疾病，根據美國統計表示顱內動脈瘤的患者約佔人口的2～3％。血管栓塞手術為現今治療顱內動脈瘤最主要的方式之一，但此方式需要具有豐富經驗醫生進行，為防止手術時間過長而造成血栓發生及管壁可能損傷。在手術過程中，醫生必須手動操控導線 (guidewire) 並藉由X光導引至顱內動脈瘤病理位置，然而，在導線行徑過程中需要通過彎曲複雜的血管，因此經常會與血管壁碰撞與摩擦而增加手術困難度。為了使病患在手術過程中具有標準及自動化，本研究利用數值模擬方式對具有病人特徵手術前後顱內動脈瘤模型進行血液動力學分析。結果顯示，壁面剪應力大小與血液流速有高度的關聯性，且在具有動脈瘤之手術前模型在完整脈動週期內，壁面剪應力值均較小，在收縮時 (t=1.16s) 平均為1.16 Pa，這可能會使內皮細胞受損而發生破裂，而在有效應力與壓力分析中，在頸部與頂部會因動脈瘤模型結構而承受較大之負荷，這也代表此處為病患血管中較脆弱之部位。本研究所獲得的知識可以利用在血管內繞道手術的改善，並且可以作為是否進行手術的參考。在未來將藉由本研究所得到之血液流場情形，進行導線操控之路徑規劃，並整合本團隊所提出之微型致動器得到具有三維影像路徑導影功能之自動化操控心血管導線系統，使用此系統可以縮短手術時間，因而降低血栓發生機率、x光照射時間及顯影劑使用。並期望將本研究之微型致動器作為輔助手動操控導線之裝置，提升手術標準化，及利用自動化系統有效控制花費，並應用於醫療資源匱乏偏遠地區。

Endovascular coiling has been extensively used for the treatment of an intracranial aneurysm. In order to realize the effect of catheter interventions pre-surgery and post-surgery hemodynamic analysis of patient-specific intracranial aneurysm models were carried out. The results showed that there was a high correlation between wall shear stress and blood flow velocity. In the complete cardiac cycle of the pre-surgery model with an aneurysm, the wall shear stress intensity was lower and the averaged WSS was 1.16 Pa during the systolic phase (t=1.16s), which may cause damage to endothelial cells and rupture can be occur. However, in the analysis of effective stress and pressure, the intensity was observed to be higher at the neck and apex of an intracranial aneurysm. The knowledge gained in this study can be used to improve the catheter intervention process and can be used as a reference for performing surgery

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