Ultrasonic flow measurement in small periodically excited capillary-phantoms

In our paper we present an experimental ultrasonic measurement set-up combined with a blood flow mimicking phantom and show results. The phantom was designed and produced in our lab and is capable of simulating periodic vessel jitter, that influences the accuracy of blood flow measured in the phantoms capillary. This flow is produced by an infusion pump. The tissue simulating body is made of glycerol, water, agar-agar and aluminium oxide, the acoustic properties of which such as speed of sound (c=1540 m/s) and attenuation coefficient (approximately 1.5 dB/MHz/cm) are adapted to human tissues. The electronics is used to store the digitized signals scattered off the interrogated phantom volume. The signal processing comprises: alignment to reduce unwanted tissue motion related artefacts, filtering of stationary and non-stationary clutter components and velocity estimation to estimate magnitudes and spatial distribution of the assumed flow. Concluding, some image processing is necessary to generate a time sequence of 3D-flow data for a total simulated heartbeat period.