迄今為止，心血管疾病一直為造成全球人口死亡的主要疾病。因此人們對於早期預防心血管疾病非常重視。在過去研究中，頸動脈 - 股動脈脈波速度已被廣泛認為是評估心血管疾病的可靠臨床參數，但此量測方法上仍有一些問題會導致量測結果有誤差。而最近有許多基於超音波成像技術來量測局部脈搏波速度已被提出，局部脈波速度可以提供更多的臨床資訊並且可作為早期診斷心血管疾病的一種工具。然而超音波成像技術上需要高解析度的影像來呈現局部脈波速度相關資訊，因此會有較複雜的運算。
在本論文中透過線性陣列換能器激發少量超音波陣元取得血管壁的訊號，採用訊號峰值收尋的方法估計血管壁的運動，並以已知陣元距離與管壁位移波形傳遞的時間之線性關係估計局部脈波速度。而該方法僅提供局部脈波速度之平均數值，以利於大量人口檢測。此方法之可靠性已在本論文中被討論，透過自製血管仿體進行體外實驗。實驗結果中發現僅透過8個超音波波束進行量測，也可以準確估計局部脈波速度。另外在薄與厚的仿體上發現該方法估計之脈波速度與Moens-Korteweg 公式推測之血管仿體理論脈波速度間有良好的一致性。
此外，在健康年輕受試者中透過提出方法估計之頸動脈脈波速度與商業儀器SphygmoCor量測之頸動脈 - 股動脈脈波速度之關係也在本論文中被討論。實驗結果顯示， 頸股動脈平均脈波速度與頸動脈平均脈波速度分別為6.82±0.49 m/s 與 4.72±0.50 m/s，且兩者間存在良好的線性相關性(r=0.82)。這些結果與先前的研究結果一致。
在本論文中，基於超音波提出了一種低運算成本、非侵入性用於測量局部脈搏波速度之方法並且確認頸股動脈脈波速度與頸動脈脈波速度的相關性。

About the major cause of the death globally has been attributed to cardiovascular diseases (CVDs) until now，such issue has drawn attention to the importance of CVDs for the early prevention. In the past studies, the Carotid–femoral pulse wave velocity (cfPWV) has been widely considered to be a reliable clinical parameter for evaluate of the CVDs risk. But this method still has some significant limitations which results into errors for cfPWV measurements. Recently, several ultrasound imaging-based methods have been proposed to measure the local PWV, that can exhibit more clinical significance and can be used as an early diagnosis tool. However, ultrasonic imaging technology requires high-resolution images to present local PWV related information, it’s usually along with complicated operations.
In this study, use a linear array transducer to excite a limited element for obtaining the signal of the vessel wall, and the wall motion estimated by the peak finding method. The local PWV was measured by the relationship between known element’s locations and pulse wave travel time. The proposed method only provides the average value of the local PWV to facilitate large population detection. The reliability of proposed method has been discussed via the in vitro experiments which performed by self-made vessel phantoms. The experimental results show that the measurement of 8 transducer beams also can be used to accurately estimate the local PWV. And the good agreement was found between reference PWVs and local PWVs on thin and thick phantoms obtained from Moens-Korteweg equation and proposed method.
On the other hand, the relationship between cfPWV and carotid PWV in young healthy subjects was also discussed in this study which obtained from SphygmoCor device and proposed method. The measured PWVs in vivo are 6.82±0.49 m/s and 4.72±0.50 m/s for cfPWV and local PWV, respectively. A good linear correlation was found between cfPWV and local PWV (r=0.82) which agree with previous study.
In this study, the low computing cost and noninvasive method based on ultrasound was proposed for measuring the local PWV and comparing the correlation between cfPWV and carotid PWV in human.

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