動脈的硬度變化和動脈病變以及相關疾病，例如動脈粥狀硬化、中風、高血壓有著高度相關。而超音波因為其非侵入式，即時成像和安全因素而被廣泛應用在檢測動脈性質上。脈衝波速度之所以成為檢測動脈彈性性質上的重要指數是因為脈衝波速度在較硬動脈上會明顯提高。而在先前的研究中，為了在臨床前實驗中去量測老鼠動脈上的脈衝波速度，結合了高頻超音波系統和心電訊號的觸發器。
在本論文中提出了一套採用雙陣元式探頭去量測脈衝波速度的系統，依靠其不需要心電訊號觸發器來獲得高頻超音波影像。系統會比較在正常老鼠和有動脈硬化老鼠上的脈衝波速度來驗證系統的正確性。在正常老鼠以及動脈硬化的老鼠中，平均脈衝波速度有著明顯的差異，在有動脈硬化的老鼠中其脈衝波速度為2.7±0.64(m/s)是遠高於普通老鼠的1.6±0.43(m/s)，也因此驗證本論文所提出系統的正確性。
另一方面，在許多研究中指出阿茲海默症會導致頸動脈的彈性發生改變，在本論文中我們將此系統方法應用在有阿茲海默症的老鼠身上並觀測與驗證是不是和人類案例有相似的結果並比較不同組別的老鼠其結果的相異性，在正常老鼠以及阿茲海默症的同齡老鼠中，平均脈衝波速度有明顯的差異，與人體上阿茲海默症會影響動脈壁的彈性並使其更易於造成動脈硬化有著相同的結果。
在本論文中,我們成功建立了在老鼠頸動脈上阿茲海默症與動脈硬化的相關性並成功開發出一套採用雙陣元式探頭去量測脈衝波速度的系統。

The stiffness of artery is highly related to the arterial disease, such as arteriosclerosis. Ultrasound modality has been used extensively to detect the properties of artery due to its noninvasive, real time, and safety consideration. The pulse wave velocity (PWV) of artery is an important index for assessing the elastic properties of artery because the PWV was increased with arterial stiffness. In order to measure the PWV of artery in mice for pre-clinical study, a combination of high frequency ultrasound system and ECG gating techniques was proposed in previous study.
A novel dual elements transducers PWV system without ECG gating synchronization was proposed to measure the sitffness of mice artery in this study. The system was verified by comparing the PWVs between the normal artery and arteriosclerostic artery in mice. The average of PWV are obvious difference between normal group and control group. The PWV is 2.7±0.64 (m/s) in control group that is faster than normal group which one is 1.6±0.43 (m/s). This results can prove the accurate in the system that was proposed in present study.
On the other hand, the stiffness of the artery wall that will be transformed by the Alzheimer's disease were proposed in previous study. In this study, we applied the system to measure the Alzheimer's disease mice and observed the results of the different groups. The average of the PWV are obvious differences between the normal mice and the Alzheimer's disease mice that are both at the same age, the results in this experiments have a same relationship in the human experiments.
In this paper, we successfully established the correlation between Alzheimer's disease and atherosclerosis in the mice carotid artery and developed a high frequency ultrasound dual-elements transducer system to measure the pulse wave velocity.

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