Determining mechanical properties via ultrasound-induced resonance

Inventors

Walker, William F. • Corey, F. Scott • Homyk, Andrew • Higgins, Tim • Viola, Francesco • Regan, Frank • Ferrante, Elisa

Assignees

Hemosonics LLC

Abstract

A device for estimating a mechanical property of a sample is disclosed herein. The device may include a chamber configured to hold the sample; a transmitter configured to transmit a plurality of waveforms, including at least one forcing waveform; and a transducer assembly operatively connected to the transmitter and configured to transform the transmit waveforms into ultrasound waveforms. The transducer assembly can also transmit and receive ultrasound waveforms into and out of the chamber, as well as transform at least two received ultrasound waveforms into received electrical waveforms. The device also includes a data processor that can receive the received electrical waveforms; estimate a difference in the received electrical waveforms that results at least partially from movement of the sample; and estimate a mechanical property of the sample by comparing at least one feature of the estimated difference to at least one predicted feature, wherein the at least one predicted feature is based on a model of an effect of the chamber wall. Finally, the device can also include a controller configured to control the timing of the ultrasound transmitter and data processor.

Core Innovation

The invention provides a device for evaluation of hemostasis using an acoustic interrogation system to measure at least one viscoelastic property of a test sample of blood. The device includes a housing and a plurality of test chambers, each having a resonant portion designed to hold test sample blood combined with a reagent or combination of reagent and to be interrogated by the acoustic interrogation system to determine a plurality of hemostatic parameters of the test samples.

Each resonant portion is configured to generate resonance from one or more acoustic pulses directed into the test chamber by the acoustic interrogation system. The resonant portion generates a shear wave that is axisymmetric, at least in part, from applied acoustic radiation force exerted by the applied one or more acoustic pulses.

The disclosed approach further includes using resonance-related motion and echo-related signal differences to estimate displacement features and thereby infer mechanical properties, including shear modulus and viscoelastic properties such as viscosity. Analytical and computational modeling, including finite difference time domain and analytical cylindrical resonance models, are used to correlate measured displacement features, such as resonance presence and resonance period or frequency, with model predictions; unreliable estimates can be masked when correlations are not reliable.

Claims Coverage

The independent claim covers a device configured for use with an acoustic interrogation system to evaluate hemostasis by measuring viscoelastic properties of blood and determining a plurality of hemostatic parameters using resonant, radiation-force-driven axisymmetric shear waves.

Overall, claim coverage centers on an acoustic interrogation device with multiple resonant test chambers that generate axisymmetric shear waves via acoustic radiation-force-induced resonance to measure viscoelastic properties of blood for determining hemostatic parameters.

Stated Advantages

Documented Applications