根據先前在脈動流模式下血管彈性之血流量測研究中顯示，在不同心律與不同血溶比的條件下，都普勒功率與流速會產生領先或落後的關係。血管彈性的定量分析結果以及與心律和血流速度的相依性仍未確定。
為了更了解此現象，利用脈動型幫浦模擬血液流動的狀態，使用豬血配置成全血與紅血球食鹽水懸浮液且在不同彈性的管中與脈動流條件下，去量測都卜勒功率。在本研究中討論三種可能會影響都卜勒功率的參數：1.心律的相關性、2.血管壁的彈性、3.不同的血流速度。本研究為10 MHz搭配 FPGA核心高頻脈衝式都卜勒超音波流速計用於模擬血流量測研究。結果顯示，在不同心律與流速下以紅血球懸浮液為樣本的實驗中沒有顯著的變化(小於2分貝)。以全血做為樣本的橡膠管實驗中，除了在實驗參數80RPM、流速60cm/s的條件下，都卜勒功率的峰值皆領先於流速的峰值。以全血做為樣本的矽膠管實驗中，在相同流速、不同心律的條件下，都卜勒功率的峰值皆從舒張的位置偏移到收縮的位置。此外心律與都卜勒功率有著明顯的相關性。隨著心律與血流速度越大，都卜勒功率的週期性變化越不明顯。最明顯的週期性變化發生在心律40RPM。
本研究與先前文獻之結果顯示在脈動流下一個週期內的都卜勒功率、心律、血流速度有很明顯的相關性，此外本研究結果顯示血管彈性也是影響都卜勒功率之因素。

Previous in vitro studies in tubes with different elasticity under pulsatile flow conditions have demonstrate that Doppler power would lead or lag flow velocity waveform in different stroke rates and hematocrit. The quantitative results of vessel elasticity, dependence on stroke rates and flow velocity are still uncertain.
To better understand this phenomenon, the Doppler power from porcine whole blood and porcine red blood cell suspensions with different tubes, under pulsatile flow conditions was measured. Three parameters that may alter the Doppler power were discussed in this study: 1. the dependence on stroke rates, 2. the effect of the vessel wall elasticity and 3. the influence of the various flow velocities. In the present study, the experimental results were obtained with a 10-MHz full digital FPGA-based pulsed wave (PW) Doppler flowmeter. The results show that the Doppler power from porcine red blood cell suspensions did not vary obviously (<2 dB), with different stroke rates and flow velocities. In porcine whole blood, the peak of Doppler power leads the flow velocity waveform in rubber tube experiments except for the lowest velocity experiment at 80RPM. At the silicon tube experiments, the power peak is shifted from the diastole to the systole at different stroke rate and fixed flow velocity. Additionally, there was an evident correlation between stroke rates and Doppler power variation. The cyclic variation of Doppler power become inconspicuous as the velocity and stroke rates increased. The apparent cyclic variation from whole blood was observed at 40RPM.
The results of this and previous studies have shown that the Doppler power from blood under pulsatile flow during a flow cycle strongly depend on the stroke rate and flow velocity. Moreover, the results demonstrate that vessel elasticity is also a factor may affect the Doppler power.

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