Tissue identifying method in ultrasonography and ultrasonograph

• US 20040260180A1
• Filed: 02/19/2004
• Published: 12/23/2004
• Est. Priority Date: 08/20/2001
• Status: Active Grant

• Current Assignee: Japan Science And Technology Agency
• Original Assignee: Japan Science And Technology Agency
• Inventors: Kanai, Hiroshi, Koiwa, Yoshiro
• Granted Patent: US 7,744,537 B2
• Time in Patent Office: Days
• US Class Current: 600/449
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/441 Skin evaluation, e.g. for skin disorder diagnosis
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: A61B 8/0858 involving measuring tissue layers, e.g. skin, interfaces
• CPC Class Codes: A61B 8/485 involving measuring strain or elastic properties

Abstract

In a method for identifying a living tissue in an ultrasonic diagnosis, the elasticity of a living tissue to be diagnosed is measured for each local small area by using ultrasound. Elasticity data for each kind of known living tissue is composed of an elasticity modulus frequency histogram in each local small area for each kind of living tissue and is managed in a data library. Regarding the elasticity data serving as the measurement results, the kind of living tissue to be diagnosed is identified by using the elastic data for each kind of known living tissue.

Claims

1. A method for identifying a living tissue in an ultrasonic diagnosis, comprising the steps of:

measuring at least an elasticity of a living tissue to be diagnosed in each local small area by using ultrasound;

managing, in a data library, at least elasticity data for each kind of known living tissue such as an adipose area, a thrombus area, an elastic fiber, a collagen fiber, and a calcified area, the elasticity data being composed of an elasticity modulus frequency histogram in each local small area for each kind of living tissue; and

identifying the kind of living tissue to be diagnosed, at least regarding the elasticity data serving as a measurement result, by using the elasticity data for each kind of known living tissue.

2. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 1, the method further comprising the steps of:

exciting a vibration on a measured part of the living tissue to be diagnosed;

measuring a shear elasticity and a shear viscosity of the excited living tissue to be diagnosed in the measurement using ultrasound;

managing viscosity data for each kind of known living tissue such as an adipose area, a thrombus area, an elastic fiber, a collagen fiber, and a calcified area in the management of the data library, the viscosity data being composed of a viscosity frequency histogram in each local small area for each kind of living tissue; and

identifying the kind of living tissue to be diagnosed, regarding the elasticity data and viscosity data serving as measurement results, by using the elasticity data and viscosity data for each kind of known living tissue in identification of the kind of living tissue to be diagnosed.

3. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 2, wherein the vibration on the measured part of the living tissue to be diagnosed is excited by a turbulent flow component or a vortex component, the components being generated by a time change in a pulse of a pulsatile flow in a blood vessel.

4. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 2, wherein the vibration on the measured part of the living tissue to be diagnosed is excited by a vibration percutaneously applied to a part away from the measured part from an outside of a body.

5. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 2, wherein in management of the data library, each kind of known living tissue is mapped on a two-dimensional plane having axes representing a shear elasticity modulus and a shear viscosity.

6. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 1, wherein the living tissue to be diagnosed is a living tissue on a heart, a blood vessel, and so on.

8. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 1, wherein the local small area serving as a unit for measuring an elasticity and/or a viscosity of the living tissue to be diagnosed is several tens to several hundreds square microns.

9. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 1, wherein the kind of living tissue to be diagnosed is identified using the elasticity data and or the viscosity data serving as measurement results, and the identification is performed by referring to the elasticity data and/or the viscosity data for each kind of known living tissue, the data being extracted from the data library, and determining the kind of known living tissue having a minimum distance.

10. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 9, wherein the kind of known living tissue having a minimum distance from the elasticity data serving as a measurement result is determined by using Bayes decision method for dispersion and an average value of elasticity moduli determined from the histogram of the elasticity data on each kind of known living tissue.

11. The method for identifying a living tissue in an ultrasonic diagnosis according to claim 1, wherein an electronic chromatic figure is generated and displayed so as to identify in colors the kind of living tissue to be diagnosed, the kind of living tissue being identified for each local small area.

7. (Deleted)

12. An ultrasonic diagnostic system, in which at least an elasticity of a living tissue to be diagnosed is measured in each local small area by using ultrasound and a tomogram is displayed, the system comprising:

a data library for managing at least elasticity data for each kind of known living tissue such as an adipose area, a thrombus area, an elastic fiber, a collagen fiber, and a calcified area, the elasticity data being composed of an elasticity modulus frequency histogram in each local small area for each kind of living tissue, and

a tissue identifying unit for identifying the kind of living tissue to be diagnosed, regarding at least the elasticity data serving as a measurement result, by using the elasticity data for each kind of know living tissue.

13. The ultrasonic diagnostic system according to claim 12, further comprising:

exciting means for exciting a vibration on a measured part of a living tissue to be diagnosed,

wherein the data library further includes viscosity data for each kind of known living tissue and manages the viscosity data for each kind of known living tissue such as an adipose area, a thrombus area, an elastic fiber, a collagen fiber, and a calcified area, the viscosity data being composed of a viscosity frequency histogram in each local small area for each kind of living tissue, and

the tissue identifying unit identifies the kind of living tissue to be diagnosed, regarding the elasticity data and viscosity data serving as measurement results of the excited living tissue to be diagnosed, by using the elasticity data and viscosity data for each kind of known living tissue.

14. The ultrasonic diagnostic system according to claim 13, wherein each kind of known living tissue is mapped on a two-dimensional plane having axes representing a shear elasticity modulus and a shear viscosity.

15. The ultrasonic diagnostic system according to claim 12, wherein the living tissue to be diagnosed is a living tissue on a heart, a blood vessel, and so on.

17. The ultrasonic diagnostic system according to claim 12, wherein the local small area serving as a unit for measuring an elasticity of the living tissue to be diagnosed is several tens to several hundreds square microns.

18. The ultrasonic diagnostic system according to claim 12, wherein the tissue identifying unit has identifying means which refers to the elasticity data for each kind of known living tissue, the data being extracted from the data library, and determines the kind of known living tissue having a minimum distance, for each elasticity data serving as a measurement result in each local small area.

19. The ultrasonic diagnostic system according to claim 18, wherein the identifying means determines dispersion and an average value of elasticity moduli from the histogram of elasticity data of each kind of known living tissue, the data being extracted from the data library, and the identifying means performs identification using Bayes decision method.

16. (Deleted)

20. The ultrasonic diagnostic system according to claim 123, wherein the tissue identifying unit has electronic chromatic figure generating means for generating an electronic chromatic figure so as to identify in colors the kind of living tissue to be diagnosed, the kind of living tissue being identified for each local small area.