Ultrasound systems and methods for measuring acoustic attenuation coefficients

Patent metadata

Field	Value
Publication number	US-2020256971-A1
Application number	US-201816648010-A
Country	US
Kind code	A1
Filing date	Sep 6, 2018
Priority date	Sep 19, 2017
Publication date	Aug 13, 2020
Grant date	—

Abstract

Systems and methods for improving spectral-shift methods for calculating acoustic attenuation coefficients are disclosed. Systems, methods, and apparatuses for transmitting ultrasound pulse sequences for improved signal-to-noise outside the main passband of ultrasound transducers are disclosed. Systems, methods, and apparatuses for using the echoes from the transmitted pulse sequences to calculate the attenuation coefficient are disclosed.

First claim

1 . A method for determining an attenuation coefficient of tissue, the method comprising:
transmitting ultrasound pulses from an ultrasound transducer towards a tissue in accordance with a pulse sequence, the pulse sequence including pulses of at least one first frequency inside and at least one second frequency outside a main passband of the ultrasound transducer; receiving echo signals that correspond to the pulses of the at least one first and the at least one second frequencies of the pulse sequence; determining an attenuation coefficient of the tissue based, at least in part, on a combination of received echo signals that correspond to the pulses of the at least one first and the at least one second frequencies; and displaying an ultrasound image concurrently with the calculated attenuation coefficient.

2 . The method of claim 1 , wherein the ultrasound image is generated from echoes received from the pulse sequence or from echoes received from at least one other pulse sequence.

3 . The method of claim 1 , wherein the calculated attenuation coefficient is displayed as a map overlaying the ultrasound image.

4 . The method of claim 3 , wherein the map is a color map.

5 . The method of claim 1 , wherein the pulse of at least one first frequency comprises a wideband pulse and the pulse of at least one second frequency comprises at least one narrowband pulse.

6 . The method of claim 5 , wherein a center frequency of the wideband pulse is within the main passband of the ultrasound transducer.

7 . The method of claim 5 , wherein a center frequency of the at least one narrowband pulse is outside the main passband of the ultrasound transducer.

8 . The method of claim 5 , wherein the at least one narrowband pulse is a combination of a plurality of narrowband pulses having different center frequencies.

9 . The method of claim 8 , wherein phases of the plurality of narrowband pulses having different center frequencies are shifted with respect to one another.

10 . The method of claim 5 , wherein a time duration of the wideband pulse is less than a time duration of the at least one narrow band pulse.

11 . The method of claim 1 , wherein the pulse sequence comprises a coded excitation.

12 . The method of claim 11 , wherein the coded excitation includes a nonlinear chirp.

13 . The method of claim 1 , wherein determining the attenuation coefficient includes a spectral-shift method.

14 . An ultrasound imaging system comprising:
an ultrasound transducer configured to transmit ultrasound pulses toward a tissue, wherein the ultrasound pulses are transmitted in accordance with a pulse sequence, the pulse sequence including pulses of at least one first frequency inside and at least one second frequency outside a main passband of the ultrasound transducer; an attenuation coefficient calculator circuit configured to calculate an attenuation coefficient of the tissue based, at least in part, on echo signals that correspond to the pulses of the at least one first and the at least one second frequencies; and
at least one processor circuit configured to generate ultrasound imaging data based on the echo signals.

15 . The ultrasound imaging system of claim 14 , wherein the ultrasound transducer is a CMUT or a piezoelectric transducer.

16 . The ultrasound imaging system of claim 14 , wherein the attenuation coefficient calculator circuit is further configured to calculate a tissue characterization based, at least in part, on the attenuation coefficient of the medium.

17 . The ultrasound imaging system of claim 14 , further comprising a pulse sequence generator configured to:
generate commands corresponding to the pulse sequence; and transmit the commands to cause the ultrasound transducer to transmit the pulse sequence.

18 . The ultrasound imaging system of claim 17 , wherein the pulse sequence generator is further configured to generate a coded excitation.

19 . The ultrasound imaging system of claim 18 , wherein the attenuation coefficient calculator circuit is further configured to decode echo signals resulting from the coded excitation.

20 . The ultrasound imaging system of claim 14 , further comprising a signal processor circuit configured to receive the echo signals, process the echo signals, and provide the processed signals to the attenuation coefficient calculator circuit.

Assignees

• Koninklijke Philips Nv

Inventors

• Huang Sheng-Wen
• Xie Hua
• Robert Jean-Luc Francois-Marie
• Nguyen Man
• Shamdasani Vijay

Classifications

• G01S15/8959

  using coded signals for correlation purposes · CPC title

• G01S7/52036 Primary

  using analysis of echo signal for target characterisation · CPC title

• G01N2291/02475

  Tissue characterisation · CPC title

• G01N29/2406

  Electrostatic or capacitive probes, e.g. electret or cMUT-probes · CPC title

• G01N29/343

  pulse waves, e.g. particular sequence of pulses, bursts · CPC title