Ultrasonic image construction method, ultrasonic image construction apparatus, ultrasonic image construction program, and skin evaluation method

Patent metadata

Field	Value
Publication number	US-11191523-B2
Application number	US-201716611498-A
Country	US
Kind code	B2
Filing date	May 10, 2017
Priority date	May 10, 2017
Publication date	Dec 7, 2021
Grant date	Dec 7, 2021

Abstract

An ultrasonic-image-construction apparatus can construct an ultrasonic-tomographic image of a thin, layer-structured target object to be measured relatively easily and highly accurately in a manner in which such layered structure is easily understood. An ultrasonic transducer of an ultrasonic-image-constructing apparatus transmits ultrasonic waves to the target object. A reference substance makes contact with a base substrate, with such ultrasonic waves being incident on the target object via the base substrate, then receives an impulse response of an ultrasonic waveform. A computing means performs calculation to estimate acoustic-physical-property distribution in consideration of the multiple-reflections influence based on normalized-impulse information obtained from impulse-response information of such ultrasonic waveform incident on the reference substance and from impulse-response information of such ultrasonic waveform incident on the target object. The image-construction means constructs acoustic-physical-property-image data based on acoustic-physical-property distribution in the depth direction obtained by computing means.

First claim

The invention claimed is:

1. An ultrasonic-image-construction method, comprising;
a transmitting-and-receiving step for transmitting ultrasonic waves at a biological tissue having a layered structure and a reference substance, wherein the biological tissue to be measured and the reference substance of known acoustic properties are in contact with a base substrate of known acoustic properties, and then receiving impulse responses of the ultrasonic waves from the biological tissue to be measured and from the reference substance, with such ultrasonic waves being incident on the biological tissue to be measured and on the reference substance through the base substrate;
a computing step for performing a calculation to estimate an acoustic impedance distribution in a depth direction of micro-transmission paths in consideration of an effect of multiple reflections based on normalized impulse-response information having been obtained from impulse-response information of the ultrasonic waves incident on the reference substance and of impulse-response information of the ultrasonic waves incident on the biological tissue to be measured;
the computing step further comprising:
i) assuming micro-transmission paths of different acoustic impedances are connected in the depth direction to form an assembly of micro-transmission paths;
ii) estimating an acoustic impedance of the micro-transmission path on a front side; and
iii) estimating an acoustic impedance of the micro-transmission path adjacent to a back side by using the estimate of the acoustic impedance of the micro-transmission path on the front side;
steps (i-iii) form part of the calculation to estimate the acoustic impedance distribution; and
in comprising an image-construction step for constructing an acoustic-property image data based on the acoustic impedance distribution in the depth direction obtained by a computer.

2. An ultrasonic image-construction method according to claim 1 , characterized in that the biological tissue to be measured is skin.

3. An ultrasonic-image-construction method according claim 1 , characterized in that the base substrate is at least partially flat and is made of a material harder than the biological tissue to be measured.

4. An ultrasonic-image-construction method according to claim 1 , characterized in that the reference substance of known acoustic properties that is different from the base substrate is already provided on the surface of the base substrate on which the biological tissue to be measured is arranged.

5. An ultrasonic-image-construction method according to claim 1 , characterized in that in the transmitting-receiving step an ultrasonic wave is incident on the biological tissue to be measured while such ultrasonic wave is relatively scanning in a one-dimensional or two-dimensional direction.

6. An ultrasonic-image-construction apparatus, comprising:
an ultrasonic transducer that transmits ultrasonic waves at a biological tissue having a layered structure and a reference substance, wherein the biological tissue to be measured and the reference substance of known acoustic properties are in contact with a base substrate of known acoustic properties, the ultrasonic transducer also receives impulse responses of the ultrasonic waves from the biological tissue to be measured and from the reference substance, with the ultrasonic waves being incident on the biological tissue to be measured and on the reference substance through the base substrate,
a computer for estimating an acoustic impedance distribution in a depth direction of micro-transmission paths path in consideration of an effect of multiple reflections based on impulse-response information of the ultrasonic waves having been incident on the reference substance and based on normalized impulse-response information having been obtained from the impulse-response information of the ultrasonic waves having been incident on the biological tissue to be measured, and
the computer further;
i) assuming micro-transmission paths of different acoustic impedances are connected in the depth direction to form an assembly of micro-transmission paths;
ii) estimating an acoustic impedance of the micro-transmission path on a front side; and
iii) estimating an acoustic impedance of the micro-transmission path adjacent to a back side by using the estimate of the acoustic impedance of the micro-transmission path on the front side;
steps (i-iii) form part of the estimate of the acoustic impedance distribution performed by the computer;
the computer configured for constructing an acoustic-property image data based on the acoustic-impedance distribution in the depth direction obtained by the computer.

7. An ultrasonic-image-construction apparatus according to claim 6 , characterized in further comprising a scanner for relatively scanning the ultrasonic transducer to the biological tissue to be measured in a one-dimensional or two-dimensional direction.

8. An ultrasonic-image-construction program to run a processor;
to execute a transmitting-and-receiving step for transmitting ultrasonic waves at a biological tissue having a layered structure and a reference substance, wherein the biological tissue to be measured and a reference substance of known acoustic properties are in contact with a base substrate of known acoustic properties, and then for receiving impulse responses of the ultrasonic waves from the biological tissue to be measured and from the reference substance, with such ultrasonic waves being incident on the biological tissue to be measured and on the reference substance through the base substrate;
to execute a calculating step for performing a calculation to estimate an acoustic impedance distribution in a depth direction of micro-transmission paths in consideration of an effect of multiple reflections based on normalized impulse-response information having been obtained from impulse-response information of the ultrasonic waves incident on the reference substance and of impulse-response information of the ultrasonic waveform incident on the biological tissue to be measured;
the executing of the calculating step further comprising:
i) assuming micro-transmission paths of different acoustic impedances are connected in the depth direction to form an assembly of micro-transmission paths;
ii) estimating an acoustic impedance of the micro-transmission path on a front side; and
iii) estimating an acoustic impedance of the micro-transmission path adjacent to a back side by using the estimate of the acoustic impedance of the micro-transmission path on the front side;
steps (i-iii) form part of the calculation to estimate the acoustic impedance distribution;
and to execute an image construction step for constructing an acoustic-property image data based on the acoustic-impedance distribution in the depth direction.

9. A cosmetic skin-evaluation method, characterized in comprising:
a transmitting-and-receiving step for transmitting ultrasonic waves at a biological tissue having a layered structure and a reference substance, wherein the biological tissue to be measured and the reference substance of known acoustic properties are placed in contact with a base substrate of known acoustic properties, and then for receiving impulse responses of the ultrasonic waves from the biological tissue to be measured and from the reference substance, with the ultrasonic waves having been incident on the biological tissue to be measured and on the reference substance through the base substrate;
a computing step for estimating an acoustic property distribution in a depth direction of micro-transmission paths in consideration of an effect of the multiple reflections based on impulse-response information of the ultrasonic wa

Assignees

• Honda Electronic
• National Univ Corporation Toyohashi Univ Of Technology
• Shiseido Co Ltd

Inventors

• Ogura Yuki
• Hozumi Naohiro
• Yoshida Sachiko
• Kobayashi Kazuto

Classifications

• A61B8/14

  Echo-tomography · CPC title

• A61B8/5207 Primary

  involving processing of raw data to produce diagnostic data, e.g. for generating an image · CPC title

• A61B8/0858

  involving measuring tissue layers, e.g. skin, interfaces · CPC title

• G01S15/8977

  using special techniques for image reconstruction, e.g. FFT, geometrical transformations, spatial deconvolution, time deconvolution · CPC title

• G01N2291/02475

  Tissue characterisation · CPC title