DocumentCode :
322326
Title :
The effect of hemodynamics, vessel wall elasticity and hematocrit on the ultrasonic Doppler power-an in-vitro study
Author :
Missaridis, Thanassis X. ; Shung, Kirk K.
Author_Institution :
Bioeng. Program, Pennsylvania State Univ., University Park, PA, USA
fYear :
1998
fDate :
9-10 Apr 1998
Firstpage :
100
Lastpage :
103
Abstract :
Two important factors that may affect the Doppler power were investigated: a) the dependence on hematocrit and b) the effect of the vessel wall elasticity. It is shown here, that at low beat rates, the peak of the mean Doppler power within the flow cycle depends on the vessel wall elasticity. When the vessel becomes more compliant, the peak is shifted from the early to the late systole. Additionally, there is a correlation between the power peak and hematocrit, which is more evident in elastic vessels. At a higher pulsation rate of 37 beats/min, a different variation scheme is observed. A drop in the power occurs near peak systole, in elastic tube experiments. This result agrees with previously reported in vivo results. The power drop is amplified as the vessel constriction increases. This result suggests that proper interpretation of cyclic variations in Doppler power requires a knowledge of hemodynamic parameters, such as the modulus of elasticity, propagation velocity or possibly the phase angle of input impedance
Keywords :
Doppler measurement; biomechanics; biomedical ultrasonics; blood vessels; elasticity; haemodynamics; cyclic variations; elastic tube experiments; elasticity modulus; flow cycle; hematocrit; in-vitro study; input impedance phase angle; peak systole; propagation velocity; pulsation rate; ultrasonic Doppler power; vessel wall elasticity; Biomedical engineering; Blood flow; Elasticity; Frequency estimation; Hemodynamics; In vitro; In vivo; Kirk field collapse effect; Pumps; Reservoirs;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Bioengineering Conference, 1998. Proceedings of the IEEE 24th Annual Northeast
Conference_Location :
Hershey, PA
Print_ISBN :
0-7803-4544-4
Type :
conf
DOI :
10.1109/NEBC.1998.664890
Filename :
664890
Link To Document :
بازگشت