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Updated: Aug 14, 2026

Blood Flow Imaging with Ultrafast Doppler
Published on: October 14, 2020
Frequency-domain characteristics and filtering of blood flow following the onset of exercise: implications for
Leonardo F Ferreira1, Allison J Harper, Thomas J Barstow
1Dept. of Anatomy and Physiology, 1A Natatorium, Kansas State Univ., Manhattan, KS 66506-0302, USA.
Abstract:
We examined the validity and usefulness of a low-pass filter (LPFILTER) to reduce point-to-point variability and enhance parameter estimation of the kinetics of blood flow (BF). Computer simulations were used to determine the power spectrum of simulated responses. Moreover, we studied the leg BF response to a single transition in four subjects during supine knee-extension exercise using three methods of data processing [beat-by-beat, average of 3 cardiac cycles (AVG3 BEATS), and LPFILTER]. The power spectrum of BF containing the kinetics information (
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