升主動脈裡的壁剪切應力 (wall shear stress ,WSS) 的變化已被證明與主動脈病如擴張、動脈瘤和夾層有關。 這種主動脈病在雙葉主動脈瓣 (biscupid aortic valve, BAV) 疾病患者中很常見。 基於四維磁共振成像 (4D Flow Magnetic resonance imaging, 4D Flow MRI) 技術獲得的數據對壁面剪應力進行可視化和分析，有利於研究血管內的異常情況，並有助於早期關節病的診斷。 壁面剪應力的視化已經開發出來，但並不通用，商業軟件成本高，部分商業軟件沒有提供詳細的量化數據。 因此，本論文的目的是開發一個可視化系統來研究血管壁剪切應力的信息，以幫助醫生診斷潛在的冠心病患者。

Alterations of wall shear stress (WSS) of the ascending aorta (AAo) have been proven to relate to aortopathies such as dilation, aneurysm, and dissection. Such aortopathies are common among patients with bicuspid aorta valve (BAV) disease. The visualization and analysis of wall shear stress based on the data acquired from the 4-dimensional magnetic resonance imaging (4D MRI) technique are beneficial in studying the abnormalities within blood vessels and assisting in the diagnosis of early arthropathies. The visualization of wall shear stress has been developed but it is not generalized. Although there is commercial software available, it comes with a high cost, and some of the commercial software does not provide detailed quantified data. Therefore, the purpose of this thesis is to develop a visualization system to study the information of wall shear stress in blood vessels to help doctors in diagnosing patients with potential aortic disease.

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