Sj. Wu et Kk. Shung, CYCLIC VARIATION OF DOPPLER POWER FROM WHOLE-BLOOD UNDER PULSATILE FLOW, Ultrasound in medicine & biology, 22(7), 1996, pp. 883-894
Citations number
26
Categorie Soggetti
Radiology,Nuclear Medicine & Medical Imaging",Acoustics
The echogenicity and Doppler power from whole blood under pulsatile fl
ow have been found to vary during the flow cycle in previous studies b
oth in vitro and in vivo, The present study was undertaken to better u
nderstand this phenomenon, Doppler power from whole blood under pulsat
ile flow was measured with a pulsed Doppler flowmeter as a function of
the flow cycle, radial position and compliance of the vessel in a moc
k flow loop, It was found that the cyclic variation is more pronounced
if the stroke rate is less than 56 beats/min and that the peak of the
Doppler power from whole blood flowing near the center stream coincid
ed with the peak of the flow velocity, However, it began to lead the v
elocity peak as the measurement site was moved away from the center st
ream, The lead increased as the radial distance was increased, The res
ults also show that the compliance of the vessel can affect, to a cert
ain extent, the magnitude of the cyclic variation, Results from intrav
ascular Doppler measurements rule out the possibility that the cyclic
variation is primarily due to the variation in attenuation caused by v
essel wall during a flow cycle.