Method of Displaying Elastic Image and Diagnostic Ultrasound System

• US 20080269606A1
• Filed: 06/09/2005
• Published: 10/30/2008
• Est. Priority Date: 06/09/2004
• Status: Active Grant

• Current Assignee: FUJIFILM Healthcare Corp. (Fujifilm Holdings Corporation)
• Original Assignee: Hitachi Medical Corporation (Hitachi, Ltd.)
• Inventors: Matsumura, Takeshi
• Granted Patent: US 8,043,216 B2
• Time in Patent Office: Days
• US Class Current: 600/438
• CPC Class Codes: A61B 2090/378 using ultrasound
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 2562/043 in a linear array
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 5/0048 Detecting, measuring or recording by applying mechanical forces or stimuli A61B5/021, A61B5/4884 and A61B9/00 take precedence
• CPC Class Codes: A61B 8/08 Detecting organic movements or changes, e.g. tumours, cysts, swellings A61B8/02 - A61B8/06 take precedence
• CPC Class Codes: A61B 8/0825 for diagnosis of the breast, e.g. mammography
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/4281 characterised by sound-transmitting media or devices for coupling the transducer to the tissue
• CPC Class Codes: A61B 8/429 characterised by determining or monitoring the contact between the transducer and the tissue
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61B 8/461 Displaying means of special interest
• CPC Class Codes: A61B 8/463 characterised by displaying multiple images or images and diagnostic data on one display composite display in devices for short-range imaging with acoustic waves G01S7/52074
• CPC Class Codes: A61B 8/485 involving measuring strain or elastic properties
• CPC Class Codes: A61B 8/5223 for extracting a diagnostic or physiological parameter from medical diagnostic data for algorithms to analyse biomedical images G06T7/0012
• CPC Class Codes: A61B 8/5238 for combining image data of patient, e.g. merging several images from different acquisition modes into one image for image registration algorithms G06T7/30
• CPC Class Codes: G01S 15/8909 using a static transducer configuration
• CPC Class Codes: G01S 15/899 Combination of imaging systems with ancillary equipment
• CPC Class Codes: G01S 7/52042 determining elastic properties of the propagation medium or of the reflective target diagnostic techniques involving the measurement of strain A61B8/485
• CPC Class Codes: G01S 7/52074 : Composite displays, e.g. split-screen displays; Combination of multiple images or of images and alphanumeric tabular information

Abstract

To carry out objective or definitive diagnosis on the basis of an elastic image regardless of experience and proficiency, a method of displaying an elastic image includes the steps of measuring ultrasound cross-section data of a cross-section region of a subject by applying pressuring to the subject, determining a physical value correlating with the elasticity of tissue in the cross-section region on the basis of the ultrasound cross-section data, generating an elastic image of the cross-section region on the basis of the physical value and displaying the elastic image on a display device, determine compression state information relating to the compression state of the cross-section region on the basis of the pressure applied to the subject, and displaying the compression state information together with the elastic image on the display device.

Claims

1. A method of displaying an elastic image comprising the steps of:

measuring ultrasound cross-section data of a cross-section region of a subject by applying pressuring to the subject;

determining a physical value correlating with the elasticity of tissue in the cross-section region on the basis of the ultrasound cross-section data;

generating an elastic image of the cross-section region on the basis of the physical value and displaying the elastic image on a display device;

determining compression state information relating to the compression state of the cross-section region on the basis of the pressure applied to the subject; and

displaying the compression state information together with the elastic image on the display device.

2. The method of displaying an elastic image according to claim 1, wherein the compression state information displayed on the display device changes in accordance with a change over time of the pressure applied to the subject.

3. The method of displaying an elastic image according to claim 1, further comprising the steps of:

determining whether or not the pressure applied to the subject is within a set range on the basis of the compression state information; and

outputting at least one of audio and image display as an alert when the pressure is not within the set range.

4. The method of displaying an elastic image according to claim 1, wherein,

the pressure applied to the subject is applied through an ultrasound transducer used in contact with the subject,

the compression state information is pressure distribution data determined in association to a long axis direction of a plurality of transducers constituting the ultrasound transducer, the long axis direction being the alignment direction of the plurality of transducers, and

the pressure distribution data is displayed on the display device as a bar graph or a line graph matching a coordinate direction corresponding to the long axis direction of the elastic image.

5. The method of displaying an elastic image according to claim 4, further comprising the steps of:

determining the deviation with respect to a reference pressure of the pressure distribution data; and

displaying the deviation on the display device as a line graph matching the coordinate direction corresponding to the long axis direction of the elastic image.

6. The method of displaying an elastic image according to claim 1, wherein,

the pressure applied to the subject is applied through an ultrasound transducer used in contact with the subject,

the compression state information is at least one set of pressure data of an average value, a variance value, a median value, a maximum value, and a minimum value of a pressure distribution determined in association with a long axis direction of a plurality of transducers constituting the ultrasound transducer, the long axis direction being the alignment direction of the plurality of transducers, and

the pressure data is juxtaposed to the elastic image and is displayed on the display device.

7. The method of displaying an elastic image according to claim 6, wherein the pressure data is at least one of a numerical value, a bar graph having a length corresponding the numerical value, a graphic representation having brightness or color corresponding to the numerical value, a bar graph having a length corresponding to the numerical value and having brightness or color corresponding to the numerical value, a simulation meter representing the numerical value with a rotational angle of a needle, a circular graphic representation having a diameter equal to the numerical value, and a graphic representation representing the numerical value by simulating the state of compression and deformation of the cross-section region.

8. The method of displaying an elastic image according to claim 1, further comprising the steps of:

measuring the ultrasound cross-section data by repeatedly changing the pressured applied to the subject;

determining the change in the pressure applied to the cross-section region; and

displaying a pressure change line graph representing the change over time in the pressure together with the elastic image on the display device.

9. The method of displaying an elastic image according to claim 8, further comprising the step of:

displaying a reference line graph on the display device in an overlapping manner on the pressure change line graph, the reference line graph being an example of a change over time of the pressure being applied to the cross-section region.

10. The method of displaying an elastic image according to claim 8, wherein, when displaying the pressure change line graph and the elastic image read out from a cine memory storing the pressure change line graph and the elastic image on the display device and when a mark is displayed on a time axis of the pressure change line graph and moved along the time axis, an elastic image corresponding to the time indicated by the mark is read out from the cine memory and is displayed.

11. The method of displaying an elastic image according to claim 8, further comprising the steps of:

freezing the pressure change line graph representing the change over time of the pressure and the elastic image;

setting a start point and an end point of one cycle of the pressure change on the pressure change line graph; and

storing the pressure change line graph corresponding to the set one cycle and the elastic image.

12. The method of displaying an elastic image according to claim 11, wherein the start point and the end point of the one cycle of the pressure change is automatically set.

32. The method of displaying an elastic image according to claim 1, wherein the compression state information includes a pressure change distribution of a change in one frame of the pressure applied to the subject.

33. The method of displaying an elastic image according to claim 1, further comprising the step of:

setting one of a stress line of interest and a region of interest on the elastic image displayed on the display device,

wherein the compression state information includes a stress change distribution along the stress line of interest of the change in one frame of stress applied to the subject and a stress change distribution included in the range of interest.

34. The method of displaying an elastic image according to claim 1, further comprising the steps of:

determining a distortion integrated value of the tissue the cross-section region as the physical value,

wherein the compression state information includes the distortion integrated value.

35. The method of displaying an elastic image according to claim 1, further comprising the step of:

applying the pressure to be applied to the subject through an ultrasound transducer used in contact with the subject,

wherein the pressure is measured by a cMUT transducer provided on the ultrasound transducer.

36. The method of displaying an elastic image according to claim 1, further comprising the step of:

applying the pressure to be applied to the subject through an ultrasound transducer used by being inserted into the subject,

wherein the pressure is measured by a pressure sensor provided on the ultrasound transducer.

13. A diagnostic ultrasound system comprising:

signal processing means for generating a cross-sectional image and an elastic image by processing a signal detected by an ultrasound transducer in contact with a subject;

pressure detecting means for determining the pressure applied to the subject;

compression state evaluation means for evaluating a compression state of the subject on the basis of pressure data determined by the pressure detecting means; and

displaying means for displaying compression state information evaluated by the compression state evaluation means in association with the elastic image.

14. The diagnostic ultrasound system according to claim 13, wherein,

the pressure detecting means includes at least one pressure sensor disposed in the vicinity of a contact surface of the subject and the ultrasound transducer, and

the compression state evaluation means generates the compression state information by carrying out statistical processing on the pressure data from the pressure sensor.

15. The diagnostic ultrasound system according to claim 14, wherein the compression state information is a combination of a numerical value corresponding to the pressure data and a unit of pressure.

16. The diagnostic ultrasound system according to claim 14, wherein the pressure sensor is aligned along a long axis direction of ultrasound transmission and reception.

17. The diagnostic ultrasound system according to claim 14, wherein the pressure sensor is a reference deforming body for measuring pressure applied to a body surface.

18. The diagnostic ultrasound system according to claim 14, wherein the pressure sensor is a group of a plurality of pressure sensors disposed along a short axis direction of a ultrasound transmission and reception surface.

19. The diagnostic ultrasound system according to claim 14, wherein,

the compression state information is at least one set of pressure data of an average value, a variance value, a median value, a maximum value, and a minimum value of a pressure distribution determined in association with a long axis direction of a plurality of transducers constituting the ultrasound transducer, the long axis direction being the alignment direction of the plurality of transducers, and

the pressure data is juxtaposed to the elastic image and is displayed on the displaying means.

20. The diagnostic ultrasound system according to claim 19, wherein the pressure data is at least one of a numerical value, a bar graph having a length corresponding the numerical value, a graphic representation having brightness or color corresponding to the numerical value, a bar graph having a length corresponding the numerical value and having brightness or color corresponding to the numerical value, a simulation meter representing the numerical value with a rotational angle of a needle, a circular graphic representation having a diameter equaling the numerical value, and a graphic representation representing the numerical value by simulating the state of compression and deformation of the cross-section region.

21. The diagnostic ultrasound system according to claim 13, wherein the compression state information is a pressure change line graph representing the change over time of the pressure applied to the subject.

22. The diagnostic ultrasound system according to claim 21, wherein the pressure state evaluation means displays a reference line graph on the displaying means in an overlapping manner on the pressure change line graph, the reference line graph being an example of a change over time of the pressure being applied to the subject.

23. The diagnostic ultrasound system according to claim 21, wherein,

a predetermined section is set, and

the set pressure change line graph and the elastic image are stored on a storage medium.

24. The diagnostic ultrasound system according to claim 21, wherein a compressed section is extracted.

25. The diagnostic ultrasound system according to claim 21, wherein,

a magnetic sensor is provided on the ultrasound transducer, and

compression state image data is generated and displayed using positional coordinate data output from the magnetic sensor.

26. The diagnostic ultrasound system according to claim 21, further comprising:

a cine memory for storing the pressure change line graph and the elastic image; and

control means for controlling the cine memory,

wherein the control means displays a mark on a time axis of the pressure change line graph when the pressure change line graph and the elastic image being read out from the cine memory are displayed on the displaying means, and an elastic image according to the time indicated by the mark is read out from the cine memory and is displayed when the mark is moved along the time axis.

27. The diagnostic ultrasound system according to claim 26, wherein the mark is controlled in a sliding manner in the time axis direction.

28. The diagnostic ultrasound system according to claim 21, wherein the control means freezes the pressure change line graph and the elastic image, sets a start point and an end point of one cycle of the pressure change on the pressure change line graph, and stores the pressure change line graph corresponding to the set one cycle and the elastic image on a recording medium.

29. The diagnostic ultrasound system according to claim 27 or 28, wherein the stored image data is played back for a set section.

30. The diagnostic ultrasound system according to claim 28, wherein the control means automatically sets the start point and the end point of the one cycle of the pressure change.

31. The diagnostic ultrasound system according to claim 13, wherein the compression state evaluation means determines whether or not the pressure applied to the subject is within a set range and outputs at least one of audio, a graphic representation, and colors as an alert when the pressure is not within the set range.

37. The diagnostic ultrasound system according to claim 13, wherein the compression state information includes a pressure change distribution of the change in one frame of pressure applied to the subject.

38. The diagnostic ultrasound system according to claim 13, further comprising:

input means for setting one of a stress line of interest and a region of interest on the elastic image displayed on the display device,

wherein the compression state evaluation means determines a stress change distribution along the stress line of interest of the change in one frame of stress applied to the subject and a stress change distribution includes in the range of interest.

39. The diagnostic ultrasound system according to claim 13, wherein the compression state evaluation means determined a distortion integrated value of the tissue of the cross-section region as compression state information.

40. The diagnostic ultrasound system according to claim 13, wherein the compression detection means is a cMUT transducer disposed in the vicinity of the contact surface of the ultrasound transducer and the subject.

41. The diagnostic ultrasound system according to claim 13, wherein,

the pressure applied to the subject is applied through an ultrasound transducer used by inserting into the subject, and

the pressure detecting means is provided on the ultrasound transducer.