U.S. patent application number 14/422752 was filed with the patent office on 2015-06-25 for ultrasonic diagnostic apparatus and control program thereof.
The applicant listed for this patent is GE MEDICAL SYSTEMS GLOBAL TECHNOLOGY COMPANY, LLC. Invention is credited to Shunichiro Tanigawa.
Application Number | 20150173719 14/422752 |
Document ID | / |
Family ID | 49080977 |
Filed Date | 2015-06-25 |
United States Patent
Application |
20150173719 |
Kind Code |
A1 |
Tanigawa; Shunichiro |
June 25, 2015 |
ULTRASONIC DIAGNOSTIC APPARATUS AND CONTROL PROGRAM THEREOF
Abstract
An ultrasonic diagnostic apparatus including an elastic image
data generating unit which generates elastic image data having
color information corresponding to strain calculated by a physical
quantity data generating unit, and a displayer which causes an
elastic image having a color corresponding to the strain to be
displayed on an ultrasound image of the biological tissue, based on
the elastic image data. The elastic image data generating unit
generates the elastic image data, based on a color conversion table
which is indicative of information of association of strain and the
color information with each other and in which the color
information changes depending on strain in a predetermined range of
strain set in advance. The displayer displays an elasticity index
image indicating an elasticity index indicative of a relative
relationship of an average value of strain in a region set to the
ultrasound image and the predetermined range of strain.
Inventors: |
Tanigawa; Shunichiro;
(Hino-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GE MEDICAL SYSTEMS GLOBAL TECHNOLOGY COMPANY, LLC |
Waukesha |
WI |
US |
|
|
Family ID: |
49080977 |
Appl. No.: |
14/422752 |
Filed: |
August 15, 2013 |
PCT Filed: |
August 15, 2013 |
PCT NO: |
PCT/US2013/055052 |
371 Date: |
February 20, 2015 |
Current U.S.
Class: |
600/438 |
Current CPC
Class: |
A61B 8/5207 20130101;
A61B 8/5223 20130101; A61B 8/5292 20130101; A61B 8/085 20130101;
A61B 8/463 20130101; A61B 8/485 20130101 |
International
Class: |
A61B 8/08 20060101
A61B008/08 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 21, 2012 |
JP |
2012-182133 |
Claims
1. An ultrasonic diagnostic apparatus comprising: a physical
quantity calculating unit which calculates a physical quantity
related to elasticity of each part in a biological tissue, based on
echo signals obtained by transmission/reception of ultrasound to
and from the biological tissue; an elastic image data generating
unit which generates elastic image data, having information
indicative of a display form corresponding to the physical quantity
calculated by the physical quantity calculating unit; and a
displayer which causes an elastic image having the display form
corresponding to the physical quantity to be displayed on an
ultrasound image of the biological tissue, based on the elastic
image data, wherein the elastic image data generating unit
generates the elastic image data, based on information, said
information being information in which the physical quantity and
the information indicative of the display form are associated with
each other, and in which the information indicative of the display
form changes depending on a physical quantity in a prescribed range
of physical quantities set in advance, and wherein the displayer
displays an elasticity index image indicating an elasticity index
indicative of a relative relationship between a value
representative of a physical quantity in a region set to the
ultrasound image and the prescribed range of physical
quantities.
2. The ultrasonic diagnostic apparatus according to claim 1,
including a value calculating unit which calculates the value.
3. The ultrasonic diagnostic apparatus according to claim 1,
including an elasticity index calculating unit which calculates the
elasticity index.
4. The ultrasonic diagnostic apparatus according to claim 1,
including an elasticity index image generating unit which generates
the elasticity index image.
5. The ultrasonic diagnostic apparatus according to claim 1,
wherein the value representative of the physical quantity in the
region is an average value of the physical quantity in the
region.
6. The ultrasonic diagnostic apparatus according to claim 5,
wherein the elasticity index is a value obtained from division of
the average value by a maximum value in the prescribed range of
physical quantities.
7. The ultrasonic diagnostic apparatus according to claim 1,
wherein the prescribed range of physical quantities is a range set
as a range of physical quantities available at a biological tissue
targeted for displaying the elastic image.
8. The ultrasonic diagnostic apparatus according to claim 1,
wherein the elastic image is an image having a color corresponding
to the physical quantity.
9. The ultrasonic diagnostic apparatus according to claim 1,
wherein the elasticity index image includes a graph indicative
changes in the elasticity index with time.
10. The ultrasonic diagnostic apparatus according to claim 1,
wherein the elasticity index image includes a bar in which the
value of the elasticity index is shown in length.
11. The ultrasonic diagnostic apparatus according to claim 1,
wherein the elasticity index image is a numeral indicative of the
value of the elasticity index.
12. The ultrasonic diagnostic apparatus according to claim 1,
wherein the elastic image is displayed in the region.
13. The ultrasonic diagnostic apparatus according to claim 1,
wherein the region is set to within the elastic image.
14. The ultrasonic diagnostic apparatus according to claim 1,
wherein the region is a region in which an elastic image is
displayed and a region set to within an elastic image, and wherein
the elasticity index image is displayed with respect to each of
said two regions.
15. The ultrasonic diagnostic apparatus according to claim 2,
including an elasticity index calculating unit which calculates the
elasticity index.
16. The ultrasonic diagnostic apparatus according to claim 2,
including an elasticity index image generating unit which generates
the elasticity index image.
17. The ultrasonic diagnostic apparatus according to claim 3,
including an elasticity index image generating unit which generates
the elasticity index image.
18. The ultrasonic diagnostic apparatus according to claim 2,
wherein the value representative of the physical quantity in the
region is an average value of the physical quantity in the
region.
19. The ultrasonic diagnostic apparatus according to claim 3,
wherein the value representative of the physical quantity in the
region is an average value of the physical quantity in the
region.
20. The ultrasonic diagnostic apparatus according to claim 4,
wherein the value representative of the physical quantity in the
region is an average value of the physical quantity in the region.
Description
BACKGROUND
[0001] Embodiments of the present invention relate to an ultrasonic
diagnostic apparatus which displays an elastic image indicative of
the hardness or softness of a biological tissue in a subject, and a
control program thereof.
[0002] An ultrasonic diagnostic apparatus which combines a normal
B-mode image and an elastic image indicative of the hardness or
softness of a biological tissue in a subject together and displays
the result of combination, has been disclosed in, for example,
Japanese Patent Publication No. 2007-282932 or the like. The
elastic image is generated in the following manner, for example. A
physical quantity related to the elasticity of the subject is first
calculated based on echo signals obtained by transmitting
ultrasound to the subject. The physical quantity is strain, for
example. An elastic image comprised of a color corresponding to the
elasticity is generated based on the calculated physical quantity
and displayed.
[0003] Meanwhile, there has recently been a demand for evaluation
of a liver disease by an ultrasonic diagnostic apparatus capable of
displaying an elastic image. Here, as for a diffuse liver disease,
the elasticity of a liver may change in entirety without changing
locally. Even in such a case, it has been desired that the
elasticity of a biological tissue is recognized by the ultrasonic
diagnostic apparatus to properly perform the evaluation of the
disease.
BRIEF SUMMARY OF THE INVENTION
[0004] An embodiment of the invention made to solve the above
problems is an ultrasonic diagnostic apparatus which is equipped
with a physical quantity calculating unit which calculates a
physical quantity related to elasticity of each part in a
biological tissue, based on echo signals obtained by
transmission/reception of ultrasound to and from the biological
tissue, an elastic image data generating unit which generates
elastic image data having information indicative of a display form
corresponding to the physical quantity calculated by the physical
quantity calculating unit, and a displayer which causes an elastic
image having the display form corresponding to the physical
quantity to be displayed on an ultrasound image of the biological
tissue, based on the elastic image data. In the ultrasonic
diagnostic apparatus, the elastic image data generating unit
generates the elastic image data, based on information, the
information being information in which the physical quantity and
the information indicative of the display form are associated with
each other, and in which the information indicative of the display
form changes depending on a physical quantity in a prescribed range
of physical quantities set in advance. The displayer displays an
elasticity index image indicating an elasticity index indicative of
a relative relationship between a typical value representative of a
physical quantity in a region set to the ultrasound image and the
prescribed range of physical quantities.
[0005] According to the above embodiment, since an elasticity index
image indicating an elasticity index indicative of a relative
relationship between a typical value representative of a physical
quantity in a region set to the ultrasound image and the prescribed
range of physical quantities is displayed, the elasticity of a
biological tissue can be shown in a quantified form. It is thus
possible to recognize the elasticity of the biological tissue and
properly perform the evaluation of a disease.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a block diagram showing one example of a schematic
configuration of an embodiment of an ultrasonic diagnostic
apparatus according to the present invention;
[0007] FIG. 2 is a block diagram illustrating a configuration of a
display controller in the ultrasonic diagnostic apparatus shown in
FIG. 1;
[0008] FIG. 3 is a diagram depicting one example of a composite
ultrasound image displayed on a displayer;
[0009] FIG. 4 is a diagram showing one example of a color
conversion table;
[0010] FIG. 5 is a diagram illustrating one example of an
elasticity index in a strain range to which a slope part of the
color conversion table is set;
[0011] FIG. 6 is a diagram for describing a comparative example in
which a color conversion table is set according to a distribution
of strain;
[0012] FIG. 7 is a diagram for describing a comparative example in
which a color conversion table is set according to a distribution
of strain;
[0013] FIG. 8 is a diagram showing a color conversion table and
elasticity indices in different strain distributions;
[0014] FIG. 9 is a diagram illustrating the displayer on which an
elasticity index bar is displayed in a modification of the first
embodiment;
[0015] FIG. 10 is a diagram showing the displayer in a second
embodiment;
[0016] FIG. 11 is a diagram illustrating the displayer in a
modification of the second embodiment; and
[0017] FIG. 12 is a diagram showing another example of an
elasticity index image.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Embodiments of the present invention will hereinafter be
described based on the accompanying drawings.
[0019] A first embodiment will first be explained based on FIGS. 1
through 8. An ultrasonic diagnostic apparatus 1 shown in FIG. 1 is
equipped with an ultrasonic probe 2, a transmit-receive beamformer
3, a B-mode data generator 4, a physical quantity data generator 5,
a display controller 6, a displayer 7, an operation unit 8, a
controller 9 and a storage unit 10.
[0020] The ultrasonic probe 2 transmits ultrasound to a subject and
receives its echoes. The transmit-receive beamformer 3 drives the
ultrasonic probe 2 under a predetermined scan condition to perform
the scanning of the ultrasound every sound ray. Also, the
transmit-receive beamformer 3 performs signal processing such as
phasing-adding processing on each echo received by the ultrasonic
probe 2. Echo data subjected to the signal processing by the
transmit-receive beamformer 3 is outputted to the B-mode data
generator 4 and the physical quantity data generator 5. The
transmit-receive beamformer 3 is one example illustrative of an
embodiment of transmit-receive beamformer in the present
invention.
[0021] The B-mode data generator 4 performs B-mode processing such
as logarithmic compression processing, envelop detection processing
or the like on the echo data outputted from the transmit-receive
beamformer 3 to thereby generate B-mode data. The B-mode data may
be stored in the storage unit 10.
[0022] The physical quantity data generator 5 calculates a physical
quantity related to the elasticity of each portion in the subject,
based on the echo data outputted from the transmit-receive
beamformer 3 to generate physical quantity data (physical quantity
calculating function). As described in, for example, Japanese
Unexamined Patent Publication No. 2008-126079, the physical
quantity data generator 5 sets correlation windows to echo data
different in time on the same sound ray at one scanning surface.
The physical quantity data generator 5 performs a correlation
computation between the correlation windows to calculate a physical
quantity related to the elasticity for each pixel, thereby
generating physical quantity data corresponding to one frame.
Accordingly, the physical quantity data corresponding to one frame
is obtained from echo data corresponding to two frames, and an
elastic image is generated as will be described later.
[0023] The physical quantity data generator 5 calculates strain as
the physical quantity related to the elasticity in the present
embodiment. That is, the physical quantity data is data about the
strain. In the present embodiment, as will be described later,
strain is calculated by the deformation of the liver due to the
pulsation of the heart or blood vessels. The physical quantity data
generator 5 is one example illustrative of an embodiment of a
physical quantity calculating unit in the present invention. The
physical quantity calculating function is one example illustrative
of an embodiment of a physical quantity calculating function in the
present invention.
[0024] The physical quantity data may be stored in the storage unit
10.
[0025] The display controller 6 is inputted with the B-mode data
from the B-mode data generator 4 and the physical quantity data
from the physical quantity data generator 5. As shown in FIG. 2,
the display controller 6 has a B-mode image data generating unit
61, an elastic image data generating unit 62, an average value
calculating unit 63, an elasticity index calculating unit 64, an
elasticity index image generating unit 65, and an image display
control unit 66.
[0026] The B-mode image data generating unit 61 performs scan
conversion based on a scan converter on the B-mode data to convert
it to B-mode image data having information indicative of brightness
corresponding to the signal intensity of each echo. The B-mode
image data has information indicative of brightness of 256 levels
of gray, for example.
[0027] The elastic image data generating unit 62 converts the
physical quantity data to information indicative of colors and
performs scan conversion based on the scan converter to generate
color elastic image data having information indicative of colors
corresponding to strain (color elastic image data generating
function). The elastic image data generating unit 62 brings
physical quantity data into gradation and generates color elastic
image data comprised of information indicative of colors assigned
to respective gradations. The details thereof will be described
later. The elastic image data generating unit 62 is one example
illustrative of an embodiment of an elastic image data generating
unit in the present invention. The color elastic image data is one
example illustrative of an embodiment of elastic image data having
information indicative of a display form corresponding to a
physical quantity in the present invention. The information
indicative of the display form is information indicative of each
color in the present embodiment. The color elastic image data
generating function is one example illustrative of an embodiment of
an elastic image data generating function in the present
invention.
[0028] The average value calculating unit 63 calculates an average
value Stav of strain calculated by the physical quantity data
generating unit 5 in a region R (refer to FIG. 3) set to a B-mode
image BI as will be described later. This average value Stav of
strain is one example illustrative of an embodiment of a value
representative of a physical quantity of a region in the present
invention. The average value calculating unit 63 is one example
illustrative of an embodiment of a value calculating unit in the
present invention.
[0029] The elasticity index calculating unit 64 calculates an
elasticity index. The elasticity index is an index of the
elasticity of a biological tissue in the region R. The elasticity
index image generating unit 65 generates an elasticity index image
indicative of the elasticity index calculated by the elasticity
index calculating unit 64. The details thereof will be explained
later. The elasticity index calculating unit 64 is one example
illustrative of an embodiment of an elasticity index calculating
unit in the present invention. The elasticity index image
generating unit 65 is one example illustrative of an embodiment of
an elasticity index image generating unit in the present
invention.
[0030] The image display control unit 66 combines the B-mode image
data and the color elastic image data together and generates image
data of a composite ultrasound image displayed on the displayer 7.
The image display control unit 66 causes the displayer 7 to display
the image data as a composite ultrasound image UI obtained by
combining a B-mode image BI and an elastic image EI (refer to FIG.
3). The elastic image EI is displayed in the region R set to the
B-mode image BI.
[0031] The B-mode image data and the color elastic image data may
be stored in the storage unit 10. The image data of the composite
ultrasound image may be stored in the storage unit 10.
[0032] The image display control unit 66 causes the displayer 7 to
display an elasticity index image InI indicative of the elasticity
index generated by the elasticity index image generating unit 65
along with the composite ultrasound image UI (refer to FIG. 3). The
image display control unit 66 is one example illustrative of an
embodiment of an image display control unit in the present
invention and performs an image display control function in the
present invention.
[0033] The displayer 7 is comprised of, for example, an LCD (Liquid
Crystal Display), a CRT (Cathode Ray Tube) or the like. The
displayer 7 is one example illustrative of an embodiment of a
displayer in the present invention.
[0034] The operation unit 8 includes a keyboard and a pointing
device (not shown) or the like for inputting instructions and
information by an operator.
[0035] The controller 9 is comprised of a CPU (Central Processing
Unit). The controller 9 reads a control program stored in the
storage unit 10 to execute functions at the respective parts of the
ultrasonic diagnostic apparatus 1, starting with the physical
quantity calculating function, the color elastic image data
generating function and the image display control function.
[0036] The storage unit 10 is, for example, an HDD (Hard Disk
Drive), or a semiconductor memory such as a RAM (Random Access
Memory), a ROM (Read Only Memory) or the like.
[0037] A description will now be made of the operation of the
ultrasonic diagnostic apparatus 1 according to the present
embodiment. The transmit-receive beamformer 3 causes the ultrasonic
probe 2 to transmit ultrasound to a biological tissue of a subject.
In the present embodiment, the ultrasound is transmitted to the
liver of the subject by the ultrasonic probe 2.
[0038] The transmit-receive beamformer 3 may cause the ultrasonic
probe 2 to alternately transmit ultrasound for generating a B-mode
image and ultrasound for generating an elastic image. Echo signals
of ultrasound transmitted from the ultrasonic probe 2 are received
by the ultrasonic probe 2.
[0039] Here, the liver is repeatedly deformed depending on the
pulsation of the heart or blood vessels. A composite ultrasound
image that has taken deformation as strain is generated based on
echo signals obtained from the liver in which such deformation has
been repeated. Specifically, when the echo signals are captured,
the B-mode data generator 4 generates B-mode data, and the physical
quantity data generator 5 calculates strain to generate physical
quantity data. Further, the B-mode image data generating unit 61
generates B-mode image data, based on the B-mode data, and the
elastic image data generating unit 62 generates color elastic image
data, based on the physical quantity data. Then, the image display
control unit 66 causes the displayer 7 to display a composite
ultrasound image UI in which a B-mode image BI based on the B-mode
image data and an elastic image EI based on the color elastic image
data are combined, as shown in FIG. 3. The composite ultrasound
image UI is a real-time image. The elastic image EI is displayed
within a region R (shown in dots).
[0040] The image display control unit 66 causes the displayer 7 to
display the elasticity index image InI as shown in FIG. 3. The
elasticity index image InI includes an elasticity index graph G
indicative of changes in elasticity index with time. The details
thereof will be described later.
[0041] A description will be made of the generation of the color
elastic image data. The elastic image data generating unit 62
converts the physical quantity data to information indicative of
colors (hereinafter called "color information"), based on a color
conversion table TA to thereby generate the color elastic image
data comprised of color information corresponding to a physical
quantity. The color information is one example illustrative of an
embodiment of information indicative of a display form in the
present invention.
[0042] The color conversion table TA will be explained. The color
conversion table TA is information in which strain and color
information are associated with each other. Color information
converted by this color conversion table TA is a prescribed number
of gradations (0 to N). For example, the number of gradations is
256 (N=255).
[0043] The color conversion table TA can be shown in the graph
shown in FIG. 4, for example. The color conversion table TA shown
in FIG. 4 takes the form of a graph having a slope part S1 and a
horizontal part Hr. In the present embodiment, a predetermined
range X of strain extending from zero to strain Stmax corresponds
to the slope part S1.
[0044] In the slope part S1, the color information is set so as to
change stepwise depending on the strain. For example, the gradation
0 is color information indicative of blue, and the gradation N is
color information indicative of red. The gradation N/2 being
gradation in the middle between the gradation 0 and the gradation N
is color information indicative of green. In this case, the color
changes from blue to green between the gradation 0 and the
gradation N/2, and the color changes from green to red between the
gradation N/2 and the gradation N. The predetermined strain range X
is one example illustrative of a predetermined range of physical
quantities in the present invention.
[0045] The maximum value Stmax of strain in the predetermined
strain range X is converted to the gradation N. Strain greater than
or equal to the maximum value Stmax is converted to the gradation
N. That is, strain is converted to the gradation N at the
horizontal part Hr. Thus, the strain greater than or equal to the
maximum value Stmax is represented in the same color (e.g., red) at
an elastic image.
[0046] The predetermined strain range X is set in advance to a
range of values of strain that the liver being targeted for the
display of an elastic image can take according to the deformation
of the liver due to the pulsation of the heart or blood vessels.
For example, the predetermined strain range X is set to such a
range that it includes from the value of strain of the normal liver
to the value of strain of a liver of cirrhosis.
[0047] The elasticity index graph G will next be explained. The
elasticity index graph G is a graph indicative of time changes in
elasticity index In. The elasticity index In indicates a relative
relationship between the average value Stav of strain in the region
R and the predetermined range X of strain. This relative
relationship means a position relationship of the average value
Stav to the predetermined strain range X. Thus, the elasticity
index In indicates in which position the average value Stav exists
with respect to the predetermined strain range X.
[0048] The elasticity index In is calculated by the elasticity
index calculating unit 64. Specifically, the elasticity index In is
calculated by the following equation (1):
In=(Average value Stav/Maximum value Stmax).times.100 (1)
[0049] The elasticity index In is a numeric value with a percent
(%) as a unit. As shown in FIG. 5, for example, when the average
value Stav of strain is of the central value of the strain range X,
the elasticity index In is 50%. It is able to recognize from such
an elasticity index In in which position the average value Stav of
strain exists within the strain range X. It is able to grasp
whether the elasticity of the region is hard or soft.
[0050] Incidentally, when the average value Stav of strain is
larger than the maximum value Stmax (Stav>Stmax), the elasticity
index In is taken as 100%.
[0051] Here, as an example compared with the present embodiment, a
description will be made of a case where a color conversion table
TA' is assumed to be set according to the distribution of strain in
the region R to generate elastic image data. In FIG. 6, reference
numeral D1 indicates the distribution of strain in the region R.
The strain distribution D1 is a distribution of strain in the
region R at a given frame.
[0052] In the color conversion table TA', a slope part S1' is set
to a predetermined strain range X' on the basis of an average value
Stav1 of strain in the strain distribution D1. Here, when the
strain distribution D1 of FIG. 6 is taken as the normal liver, for
example, the average value Stav1 is represented in green in an
elastic image EI. On the other hand, assuming that a strain
distribution D2 shown in FIG. 7 is a strain distribution about a
liver hardened over its entirety, a slope part S1' is set to a
predetermined strain range X' on the basis of an average value
Stav2 of strain in the strain distribution D2. Even in the elastic
image EI generated based on the color conversion table TA' to which
such a slope part S1' is set, the average value Stav2 is
represented in green in the elastic image EI. Thus, when the color
conversion table TA' is set according to the distribution of
strain, there is no difference in elastic image between the liver
hardened over its entirety like cirrhosis and the normal liver.
[0053] On the other hand, as in the present embodiment, the strain
range to which the slope part S1 of the color conversion table TA
is set, is fixed to a predetermined strain range X. The elastic
index In indicative of the average value being located in any
position is calculated in the range X. Therefore, the elastic index
In becomes different values between the liver hardened over its
entirety like cirrhosis and the normal liver. As shown in FIG. 8,
for example, an elastic index In1 of an average value Stav1 of
strain in the strain distribution D1 (the same strain distribution
as in FIG. 6), and an elastic index In2 of an average value Stav2
of strain in the strain distribution D2 (the same strain
distribution as in FIG. 7) become different values
(In1>In2).
[0054] The elasticity index In is calculated for each frame of the
elastic image EI. The elasticity index image generating unit 65
generates an elasticity index graph G indicative of time changes in
the elasticity index In. The elasticity index graph G is displayed
on the displayer 7 by the image display control unit 66.
[0055] The elasticity index image InI including the elasticity
index graph G will be explained. The elasticity index image InI has
a left line L1 (line), a right line R1, a zero point mark M, and an
indication line F1 in addition to the elasticity index graph G. The
elasticity index graph G is represented between the left line L1
and the right line R1. Between the left line L1 and the right line
R1, the vertical direction indicates the size of an elasticity
index In, and the horizontal direction indicates time. The zero
point mark M means that the elasticity index In is 0%. The upper
ends of the left line L1 and the right line R1 means that the
elasticity index is 100%.
[0056] A point of intersection of the indication line F1 and the
elasticity index graph G indicates an elasticity index In of an
elastic image EI displayed on the displayer 7 at present. The
indication line F1 moves in the right direction with the elapse of
time. With the movement of the indication line F1, the elasticity
index graph G is updated.
[0057] According to the present embodiment as described above,
since the elasticity index graph G is displayed, the elasticity of
a biological tissue can be shown in a quantified form. It is able
to recognize by the elasticity index graph G, time changes in the
strain of the biological tissue, repeated according to the heart
rate or the pulsation of blood vessels, for example. It is thus
possible to perform the evaluation of a disease in detail.
[0058] A modification of the first embodiment will next be
explained. In this modification, an elasticity index bar Ba is
displayed as the elasticity index image InI as shown in FIG. 9. The
elasticity index bar Ba is displayed at a part of which the
background is black, and has a colored part Cl and a white part Wh.
The length of the colored part Cl indicates the value of the
elasticity index In. If the elasticity index In is 50%, for
example, the colored part Cl becomes half of the overall length of
the elasticity index bar Ba, and the white part Wh also becomes
half of the overall length of the elasticity index bar Ba.
[0059] In the colored part Cl, the color thereof may be changed
depending on the value of the elasticity index In. When the
elasticity index In is greater than or equal to 0% and less than
30%, for example, the colored part Cl may be blue. When the
elasticity index In is greater than or equal to 30% and less than
60%, the colored part Cl may be green. When the elasticity index In
is greater than or equal to 60% and less than or equal to 100%, the
colored part Cl may be red. The above numerical range and colors
are however one example and not limited to the above.
[0060] As in this modification, the elasticity of a biological
tissue can be shown in a quantified form even by the display of the
elasticity index bar Ba.
[0061] A second embodiment will next be described. Description of
the same items as those in the first embodiment is however
omitted.
[0062] In the present embodiment, as shown in FIG. 10, a first
region R1 is set to a B-mode image BI displayed on the displayer 7.
Further, a second region R2 is set to within the first region R1.
The image EI is displayed in the first region R1 including the
second region R2. For example, the second region R2 is set to a
region that an operator takes interest in particularly within the
first region R1.
[0063] In the present embodiment, the elasticity index calculating
unit 64 calculates a first elasticity index In1 indicative of in
which position an average value StavR1 of strain in the first
region R1 exists within the predetermined strain range X, by the
following (equation 2):
In1=(Average value StavR1/Maximum value Stmax).times.100 (2)
[0064] Also the elasticity index calculating unit 64 calculates a
second elasticity index In2 indicative of in which position an
average value StavR2 of strain in the second region R2 exists
within the predetermined strain range X, by the following (equation
3):
In2=(Average value StavR2/Maximum value Stmax).times.100 (3)
[0065] The elasticity index image generating unit 65 generates a
first elasticity index graph G1 indicative of time changes in the
first elasticity index In1. Also the elasticity index image
generating unit 65 generates a second elasticity index graph G2
indicative of time changes in the second elasticity index In2.
[0066] The image display control unit 66 causes the displayer 7 to
display a first elasticity index image InI1 and a second elasticity
index image InI2 as the elasticity index image InI as shown in FIG.
10. The first elasticity index image InI1 includes the first
elasticity index graph G1 indicative of the time changes in the
first elasticity index In1. The second elasticity index image InI2
includes the second elasticity index graph G2 indicative of the
time changes in the second elasticity index In2. The first
elasticity index image InI1 and the second elasticity index image
InI2 are identical in configuration to the elasticity index image
InI of the first embodiment, and their detailed description is
therefore omitted.
[0067] According to the present embodiment described above, since
the first elasticity index graph G1 and the second elasticity index
graph G2 are displayed with respect to the first region R1 and the
second region R2, the elasticity of the biological tissue in the
two regions can be displayed in the quantified form. Time changes
in the strain of the biological tissue in the two regions can be
recognized by the first elasticity index graph G1 and the second
elasticity index graph G2. It is thus possible to perform the
evaluation of a disease in detail.
[0068] A modification of the second embodiment will next be
explained. In this modification, as with the modification of the
first embodiment, as shown in FIG. 11, a first elasticity index bar
Ba1 may be displayed as the first elasticity index image InI1, and
a second elasticity index bar Ba2 may be displayed as the second
elasticity index image InI2. The first elasticity index bar Ba1 is
an image indicative of the value of the first elasticity index In1.
The second elasticity index bar Ba2 is an image indicative of the
value of the second elasticity index In2. The first elasticity
index bar Ba1 and the second elasticity index bar Ba2 are identical
in configuration to the elasticity index bar Ba in the modification
of the first embodiment, and their detailed description is
therefore omitted.
[0069] Although the present invention has been described above by
the respective embodiments, it is needless to say that the present
invention can be changed in various ways within the scope that does
not change the gist of the invention. For example, although the
elasticity index In is taken as 100% where the average value Stav
of strain becomes larger than the maximum value Stmax in the above
embodiment, the value obtained in each of the above equations (1),
(2) and (3) may be defined as an elasticity index as it is.
Accordingly, the value that exceeds 100% may be calculated as an
elasticity index.
[0070] The elasticity index image InI may be a numeric value
indicative of the value of an elasticity index In as shown in FIG.
12.
[0071] Further, in the second embodiment, the elasticity index
image InI2 may be displayed only with respect to the region R2.
[0072] In the above equations (1) through (3), their common
denominators are numeric values each indicative of the size of the
range X of strain. When the minimum value of the strain range X is
not zero, the difference between the maximum value of the strain
range X and its minimum value becomes a common denominator.
[0073] The composite ultrasound image UI is not limited to the
real-time image, but may be an image based on the data stored in
the storage unit 10.
[0074] This written description uses examples to disclose the
present invention, including the best mode, and also to enable any
person skilled in the art to practice the present invention,
including making and using any computing system or systems and
performing any incorporated methods. The patentable scope of the
present invention is defined by the claims, and may include other
examples that occur to those skilled in the art. Such other
examples are intended to be within the scope of the claims if they
have structural elements that do not differ from the literal
language of the claims, or if they include equivalent structural
elements with insubstantial differences from the literal language
of the claims.
* * * * *