Ultrasonic measurement method, ultrasonic measurement apparatus, and program storage device readable by machine

Patent metadata

Field	Value
Publication number	US-11224401-B2
Application number	US-202016841812-A
Country	US
Kind code	B2
Filing date	Apr 7, 2020
Priority date	Apr 17, 2019
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

An ultrasonic measurement method includes irradiating an object to be measured with an ultrasonic wave, acquiring a reflection wave from the object, calculating at a processor an acoustic impedance in a depth direction of the object from the reflection wave, and estimating and outputting a thickness of the object based upon an inflection point determined by second-order differentiation of the acoustic impedance.

First claim

What is claimed is:

1. An ultrasonic measurement method comprising:
irradiating an object to be measured with an ultrasonic wave;
acquiring a reflection wave from the object,
calculating at a processor an acoustic impedance in a depth direction of the object from the reflection wave; and
estimating and outputting a thickness of the object based upon an inflection point determined by second-order differentiation of the acoustic impedance.

2. The ultrasonic measurement method as claimed in claim 1 ,
wherein the object to be measured is an outermost layer of a multilayer structure, and
wherein a distance from a first inflection point that first exceeds a predetermined threshold level in the depth direction to a next inflection point located deeper than the first inflection point and at which a sign of a curvature of a rate of change of the acoustic impedance is flipped from negative to positive, is output as the thickness.

3. The ultrasonic measurement method as claimed in claim 2 ,
wherein the first inflection point and the next inflection point are determined by a second-order differentiation filtering process.

4. The ultrasonic measurement method as claimed in claim 1 , further comprising:
outputting an evaluation value of stiffness or elasticity of the object based upon at least one of the thickness and a calculation value of the acoustic impedance.

5. The ultrasonic measurement method as claimed in claim 1 , further comprising:
generating and outputting an image representing a characteristic of the object to be measured based upon a distribution of the acoustic impedance in the depth direction.

6. The ultrasonic measurement method as claimed in claim 1 ,
wherein the object to be measured is a biological membrane.

7. The ultrasonic measurement method as claimed in claim 1 ,
wherein the object to be measured is human skin, and an estimation value of a skin age is output based upon the thickness.

8. A program storage device readable by a machine comprising:
a memory that stores an ultrasonic measurement program, the ultrasonic measurement program causing the machine to execute procedures of
acquiring a reflection signal of an ultrasonic wave reflected from an object to be measured;
calculating an acoustic impedance in a depth direction of the object from the reflection signal;
estimating a thickness of the object based upon an inflection point determined by a second derivative of the acoustic impedance; and
outputting an estimation value of the thickness.

9. An ultrasonic measurement apparatus: comprising:
an ultrasonic measuring instrument configured to irradiate an object to be measured with an ultrasonic wave and receive a reflection wave from the object; and
a processor that calculates an acoustic impedance in a depth direction of the object based upon the reflection wave, and outputs an estimation value of a thickness of the object based upon an inflection point determined from a second derivative of the acoustic impedance.

10. The ultrasonic measurement apparatus as claimed in claim 9 ,
wherein the processor outputs an evaluation value of stiffness or elasticity of the object based upon at least one of the thickness and a calculation value of the acoustic impedance.

11. The ultrasonic measurement apparatus as claimed in claim 9 , further comprising:
a display device,
wherein the processor generates an image representing a characteristic of the object to be measured based upon a distribution of the acoustic impedance in the depth direction, and
the display device displays the image generated by the processor.

Assignees

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

Inventors

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

Classifications

• A61B8/0858 Primary

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

• A61B8/485

  involving measuring strain or elastic properties · CPC title

• A61B8/461

  Displaying means of special interest · CPC title

• G01B17/02

  for measuring thickness · CPC title

• G01B17/025

  for measuring thickness of coating · CPC title