U.S. patent application number 13/111308 was filed with the patent office on 2012-06-14 for ultrasound diagnostic apparatus and method of displaying an ultrasound image.
Invention is credited to Yayoi Abe, Masafumi Ogasawara.
Application Number | 20120150037 13/111308 |
Document ID | / |
Family ID | 44973043 |
Filed Date | 2012-06-14 |
United States Patent
Application |
20120150037 |
Kind Code |
A9 |
Abe; Yayoi ; et al. |
June 14, 2012 |
ULTRASOUND DIAGNOSTIC APPARATUS AND METHOD OF DISPLAYING AN
ULTRASOUND IMAGE
Abstract
An ultrasound diagnostic apparatus includes an ultrasound probe,
a location sensor that detects a location of the ultrasound probe,
and a location calculation device configured to calculate a
location of echo data in a first three-dimensional coordinate
system having a certain point as an origin based on the probe
location. A deformation calculation device performs a deformation
calculation to deform a shape of the body tissue in either an
ultrasound image or a medical image captured by a medical imaging
apparatus other than the ultrasound diagnostic apparatus to a shape
of the body tissue of the other image. A display image control
device performs a coordinate conversion between the coordinate
system of the ultrasound image and a coordinate system of the
medical image and displays a deformed image based on the
deformation calculation and the other image about a same
cross-section on a display device.
Inventors: |
Abe; Yayoi; (Tokyo, JP)
; Ogasawara; Masafumi; (Tokyo, JP) |
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20110288415 A1 |
November 24, 2011 |
|
|
Family ID: |
44973043 |
Appl. No.: |
13/111308 |
Filed: |
May 19, 2011 |
Current U.S.
Class: |
600/443 |
Current CPC
Class: |
A61B 8/4254
20130101 |
Class at
Publication: |
600/443 |
International
Class: |
A61B 8/14 20060101
A61B008/14 |
Foreign Application Data
Date |
Code |
Application Number |
May 19, 2010 |
JP |
2010-115092 |
Claims
1. An ultrasound diagnostic apparatus comprising: an ultrasound
probe configured to transmit ultrasound waves to a subject and
receive an echo, the subject including body tissue; a location
sensor configured to detect a location of the ultrasound probe; a
location calculation device configured to calculate a location of
echo data in a first coordinate system in a three-dimensional space
having a certain point as an origin based on the probe location
detected by the location sensor; a deformation calculation device
configured to perform a deformation calculation to deform a shape
of the body tissue in a first image of an ultrasound image based on
the echo data and a medical image captured in advance by a medical
imaging apparatus other than the ultrasound diagnostic apparatus to
a shape of the body tissue of a second image of the ultrasound
image and the medical image, the ultrasound image having the first
coordinate system; and a display image control device configured
to: perform a coordinate conversion between the first coordinate
system of the ultrasound image and a second coordinate system of
the medical image; and display a deformed image based on the
deformation calculation by the deformation calculation device and
the second image about a same cross-section on a display
device.
2. The ultrasound diagnostic apparatus of claim 1, wherein the
deformation calculation device is configured to perform the
deformation calculation using one of a particle method and a finite
element method.
3. The ultrasound diagnostic apparatus of claim 2, wherein the
deformation calculation device is configured to perform the
deformation calculation assuming a stress acting on the body tissue
in the second image based on the first image.
4. The ultrasound diagnostic apparatus according to claim 1,
wherein the body tissue is a breast.
5. The ultrasound diagnostic apparatus according to claim 2,
wherein the body tissue is a breast.
6. The ultrasound diagnostic apparatus of claim 4, wherein the
deformation calculation device is configured to perform the
deformation calculation by one of a particle method and a finite
element method assuming that the breast is an
uncompressed-hyperelastic body formed on a rigid body.
7. The ultrasound diagnostic apparatus of claim 5, wherein the
deformation calculation device is configured to perform the
deformation calculation assuming that the breast is an
uncompressed-hyperelastic body formed on a rigid body.
8. The ultrasound diagnostic apparatus of claim 6, wherein the
deformation calculation device is configured to perform the
deformation calculation assuming that the breast in the ultrasound
image and the medical image is one of an uncompressed-hyperelastic
body provided on a lower surface of a rigid body in a horizontal
position, the uncompressed-hyperelastic body provided on an upper
surface of the rigid body in the horizontal position, and the
uncompressed-hyperelastic body provided on one surface of the rigid
body in a vertical position.
9. The ultrasound diagnostic apparatus of claim 7, wherein the
deformation calculation device is configured to perform the
deformation calculation assuming that the breast in the ultrasound
image and the medical image is one of an uncompressed-hyperelastic
body provided on a lower surface of a rigid body in a horizontal
position, the uncompressed-hyperelastic body provided on an upper
surface of the rigid body in the horizontal position, and the
uncompressed-hyperelastic body provided on one surface of the rigid
body in a vertical position.
10. The ultrasound diagnostic apparatus of claim 8, wherein the
deformation calculation device is configured to perform the
deformation calculation assuming that the breast in the ultrasound
image is one of the uncompressed-hyperelastic body provided on the
upper surface of the rigid body in the horizontal position and the
uncompressed-hyperelastic body provided on the one surface of the
rigid body in the vertical position, and the breast in the medical
image is the uncompressed-hyperelastic body provided on the lower
surface of the rigid body in the horizontal position.
11. The ultrasound diagnostic apparatus according to claim 1,
wherein the deformation calculation device is configured to perform
the deformation calculation to deform a shape of the body tissue in
the ultrasound image to a shape of the body tissue in the medical
image.
12. The ultrasound diagnostic apparatus according to claim 1,
wherein the display image control device is configured to covert
the echo data by a scan conversion to generate the ultrasound
image.
13. The ultrasound diagnostic apparatus of claim 12, wherein a
target of the deformation calculation is one of the echo data
before the scan conversion and ultrasound image data after the scan
conversion.
14. The ultrasound diagnostic apparatus according to claim 1,
wherein the deformation calculation device is configured to perform
the deformation calculation to deform a shape of the body tissue in
the medical image to a shape of the body tissue in the ultrasound
image.
15. The ultrasound diagnostic apparatus according to claim 1,
further comprising a memory configured to store medical image
data.
16. The ultrasound diagnostic apparatus of claim 15, wherein the
ultrasound image is an image in real time and the medical image is
an image based on the data stored in the memory.
17. The ultrasound diagnostic apparatus of claim 15, wherein the
ultrasound image is an image based on data captured and stored in
advance by transmitting/receiving ultrasound waves using the
ultrasound probe, and the medical image is an image based on the
data stored in the memory.
18. The ultrasound diagnostic apparatus according to claim 1,
wherein the display image control device is configured to display
the deformed image and the second image side-by-side on the display
device.
19. The ultrasound diagnostic apparatus according to claim 1,
wherein the display image control device is configured to display
the deformed image overlaid on the second image on the display
device.
20. A method of displaying an ultrasound image comprising:
performing a deformation calculation to deform a shape of a body
tissue in a first image of an ultrasound image based on echo data
and a medical image captured in advance by a medical imaging
apparatus other than an ultrasound diagnostic apparatus to a shape
of the body tissue a second image of the ultrasound image and the
medical image, the deformation calculation producing a deformed
image; performing a coordinate conversion between a
three-dimensional coordinate system of the ultrasound image and a
coordinate system of the medical image; and displaying the deformed
image and the second image about a same cross-section on a display
device.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Japanese Patent
Application No. 2010-115092 filed May 19, 2010, which is hereby
incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] The embodiments described herein relate generally to an
ultrasound diagnostic apparatus displaying ultrasound images and
medical images other than the ultrasound images.
[0003] A conventional ultrasound diagnostic apparatus transmits
ultrasound waves to a subject by touching an ultrasound probe on
the body surface of the subject and generates and displays an
ultrasound image based on the acquired echo data. Examples of
medical images other than the ultrasound images include an MRI
(Magnetic Resonance Imaging) image and an X-ray CT (Computed
Tomography) image. Japan Unexamined Patent Application No.
10-151131 discloses an ultrasound diagnostic apparatus that
displays an ultrasound image and an MRI image or an ultrasound
image and a CT image side-by-side.
[0004] When an ultrasound image and a medical image other than the
ultrasound image about the same cross-section are displayed in the
ultrasound diagnostic apparatus, shapes of the body tissue in each
image may be different despite the same cross-section due to
different postures at capturing an image. For example, when a
breast is imaged by the ultrasound diagnostic apparatus, it is
imaged in the supine position. On the other hand, when a breast is
imaged by the MRI apparatus, it is imaged in the prone position.
Thus, the breast in the ultrasound image appears squashed by its
weight, and the breast in the MRI image hangs by gravity so that
each shape in respective images is different.
[0005] Because of this, in the case displaying the ultrasound image
and the medical image other than the ultrasound image together, it
is desirable to display images showing identical shapes of the body
tissue about the same cross-section for diagnosis.
BRIEF DESCRIPTION OF THE INVENTION
[0006] A first aspect of the invention is an ultrasound diagnostic
apparatus including an ultrasound probe transmitting ultrasound
waves to a subject and receiving an echo; a location sensor for
detecting a location of the ultrasound probe; a location
calculation device calculating a location of the echo data at a
coordinate system in a three-dimension space with a certain point
as an origin based on information detected by the location sensor;
a deformation calculation device for performing a deformation
calculation to deform a shape of the body tissue in either an
ultrasound image based on the echo data or a medical image captured
in advance by a medical imaging apparatus other than an ultrasound
diagnostic apparatus to a shape of a body tissue of the other
image; and a display image control device for performing a
coordinate conversion between the coordinate system of an
ultrasound image which is in the coordinate system of the
three-dimensional space and a coordinate system of the medical
image, and for displaying a deformed image based on the data
acquired by the deformation calculation device and the other image
about the same cross-section on a display device.
[0007] In a second aspect of the invention according to the first
aspect, the deformation calculation device performs a deformation
calculation using the particle method or the finite element
method.
[0008] In a third aspect of the invention according to the second
aspect, the deformation calculation device performs a deformation
calculation assuming a stress on a body tissue in the other image
based on the one image.
[0009] In a fourth aspect of the invention according to the
ultrasound diagnostic apparatus according to any of preceding
aspects, the body tissue is a breast.
[0010] In a fifth aspect of the invention according to the fourth
aspect, the deformation calculation device performs a deformation
calculation by the particle method or the finite element method on
assumption that an uncompressed-hyperelastic body formed on a rigid
body is a breast.
[0011] In a sixth aspect of the invention according to the fifth
aspect, the deformation calculation device performs a deformation
calculation using the particle method or the finite element method
on assumption that a breast in the ultrasound image and the medical
image is one of an uncompressed-hyperelastic body provided on lower
surface of a rigid body in a horizontal position, an
uncompressed-hyperelastic body provided on upper surface of a rigid
body in a horizontal position, or an uncompressed-hyperelastic body
provided on one surface of a rigid body in a vertical position.
[0012] In a seventh aspect of the invention according to the sixth
aspect, the deformation calculation device performs a deformation
calculation using the particle method or the finite element method
on assumption that a breast in the ultrasound image is an
uncompressed-hyperelastic body provided on upper surface of a rigid
body in a horizontal position or an uncompressed-hyperelastic body
provided on one surface of a rigid body in a vertical position, and
a breast in the medical image is an uncompressed-hyperelastic body
provided on lower surface of a rigid body in a horizontal
position.
[0013] In an eighth aspect of the invention according to any of
preceding aspects, the deformation calculation device performs a
deformation calculation for deforming a shape of a body tissue in
the ultrasound image to a shape of a body tissue in the medical
image.
[0014] In a ninth aspect of the invention according to any of
preceding aspects, the display image control device converts the
echo data by a scan conversion to generate an ultrasound image.
[0015] A tenth aspect of the invention is the ultrasound diagnostic
apparatus of ninth aspect, wherein a target of the deformation
calculation is the echo data before scan conversion by the scan
converter or an ultrasound image data after scan conversion by the
scan converter.
[0016] In an eleventh aspect of the invention according to any of
aspect of the first through seventh aspects, the deformation
calculation device performs a deformation calculation for deforming
a shape of a body tissue in the medical image to a shape of a body
tissue in the ultrasound image.
[0017] In a twelfth aspect of the invention according to any of
preceding aspects, further including a memory for storing the
medical image data.
[0018] In a thirteenth aspect of the invention according to the
twelfth aspect, the ultrasound image is an image in real time and
the medical image is an image based on the data stored in the
memory.
[0019] In a fourteenth aspect of the invention according to the
twelfth aspect, the ultrasound image is an image based on data
captured and stored in advance by transmitting/receiving ultrasound
waves by the ultrasound probe, and the medical image is an image
based on the data stored in the memory.
[0020] In a fifteenth aspect of the invention according to any of
preceding aspects, the display image control device displays the
deformed image and the other image side-by-side on the display
device.
[0021] In a sixteenth aspect of the invention according to any of
preceding aspects, wherein the display image control device
displays the deformed image overlaid on the other image overlaid on
the display device.
[0022] According to the embodiments in the above-mentioned aspects,
deformed images are generated by performing a deformation
calculation to deform a shape of the body tissue in any one of the
ultrasound image and the medical image to a shape of the body
tissue in the other image. Then, coordinate conversion between a
coordinate system of the ultrasound image and a coordinate system
of the medical image is performed, and the deformed image and the
other image about the same cross-section are displayed. Because of
this, the ultrasound image and the medical image displaying
identical shapes of the body tissue at the same cross-section can
be displayed.
[0023] Further, for example, even if the shape of the body tissue
in both images are different due to the postures of the subject
when capturing the ultrasound image and the medical image, the
shape after deformation of the body tissue can be calculated by
performing a deformation calculation using the particle method or
the finite element method.
[0024] Further objects and advantages of the present invention will
be apparent from the following description of the preferred
embodiments of the invention as illustrated in the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a block diagram showing one example of a schematic
configuration of an embodiment of an ultrasound diagnostic
apparatus.
[0026] FIG. 2 is a block diagram showing the configuration of a
display control device in the ultrasound diagnostic apparatus shown
in FIG. 1.
[0027] FIG. 3 is a block diagram showing the configuration of a
control device in the ultrasound diagnostic apparatus shown in FIG.
1.
[0028] FIG. 4 is a flow chart showing a process of the ultrasound
diagnostic apparatus of the first embodiment.
[0029] FIG. 5A shows a shape of a breast at capturing an image by
an MRI apparatus.
[0030] FIG. 5B shows a shape of a breast at capturing an image by
an ultrasound diagnostic apparatus.
[0031] FIG. 6A shows a condition that an uncompressed-hyperelastic
body hangs down from the lower surface of a rigid body.
[0032] FIG. 6B shows a condition that an uncompressed-hyperelastic
body is pressed by its weight to the upper surface of a rigid
body.
[0033] FIG. 7 shows a display device where an ultrasound image and
a deformed MRI image at the same cross-section are displayed
side-by-side.
[0034] FIG. 8 explains a deformation calculation in alternative
example of the first embodiment.
[0035] FIG. 9 is a flow chart showing a process in the ultrasound
diagnostic apparatus of the second embodiment.
[0036] FIG. 10A shows a condition that an uncompressed-hyperelastic
body is pressed by its weight to the upper surface of a rigid
body.
[0037] FIG. 10B shows a condition that an uncompressed-hyperelastic
body hangs down from the lower surface of a rigid body.
[0038] FIG. 11 shows a display device where an ultrasound image and
a deformed MRI image about the same cross-section are displayed
side-by-side in the second embodiment.
[0039] FIG. 12 shows a display device where ultrasound image and a
deformed MRI image at the same cross-section are overlaid and
displayed about the same cross-section.
[0040] FIG. 13 shows a display device where a deformed ultrasound
image and an MRI image at the same cross-section are overlaid and
displayed about the same cross-section.
DETAILED DESCRIPTION OF THE INVENTION
[0041] Embodiments of the invention will be explained.
First Embodiment
[0042] First of all, a first embodiment is explained based on FIG.
1 through FIG. 7. An ultrasound diagnostic apparatus 1 shown in
FIG. 1 includes an ultrasound probe 2, a transmitting/receiving
device 3, an echo data processing device 4, a display control
device 5, a display device 6, an operation device 7, a control
device 8, a HDD (Hard Disk Driver) 9, a magnetic field generation
device 10, and a magnetic sensor 11.
[0043] The ultrasound probe 2 is configured with an array of
ultrasound transducers (not shown), and the ultrasound transducers
transmit ultrasound waves to a subject and receive its echo
signal.
[0044] The magnetic sensor 11 includes hall elements and is
provided on the ultrasound probe 2, for example. Magnetic field
generated from the magnetic field generation device 10 including a
magnetic field generation coil is detected by the magnetic sensor
11. The signal detected at the magnetic sensor 11 is input to the
display control device 5. The signal by the magnetic sensor 11 can
be input to the display control device 5 via a cable that is not
illustrated, or can be input without wires. The magnetic field
generation device 10 and the magnetic sensor 11 are examples of
embodiments of a positioning sensor.
[0045] The transmitting/receiving device 3 activates the ultrasound
probe 2 at a certain transmitting condition and makes the
ultrasound beam scan a scan plane in line-serial procedure. The
transmitting/receiving device 3 activates the ultrasound probe 2 by
a control signal from the control device 8.
[0046] The transmitting/receiving device 3 performs a signal
processing, such as phasing/adding process for the acquired echo
signal by the ultrasound probe 2, and then outputs the processed
echo data to the echo data processing device 4.
[0047] The echo data processing device 4 performs a predetermined
process, such as a logarithmic compression process or an envelope
demodulation process, to the echo data output from the
transmitting/receiving device 3.
[0048] The display control device 5 has a location calculation
device 51, a memory 52, and a display image control device 53. The
location calculation device 51 calculates information of the
location and the tilt of the ultrasound probe 2 (herein after it is
referred as "probe location information") in a space of three
dimensions with the origin of the magnetic field generation device
10 based on a magnetic field detection signal from the magnetic
sensor 11. Further, the location calculation device 51 calculates
the location information of an echo data in the space of three
dimensions based on the probe location information. A coordination
system with their origin at the magnetic field generation device 10
is one example of embodiments of the coordination system of the
ultrasound image. Also the location calculation device 51 is one
example of embodiments of the location calculation device.
[0049] The memory 52 includes a semiconductor memory, such as RAM
(Random Access Memory) or ROM (Read Only Memory). For example, the
echo data output from the echo data processing device 4, which will
be converted to the ultrasound image data in the display image
control device 53, which will be discussed later, is stored in the
memory 52. The data before being converted to the ultrasound image
data is referred as raw data. The raw data can be stored in the HDD
9.
[0050] The medical image data captured by a medical imaging
apparatus other than the ultrasound diagnostic apparatus 1 is
stored in the memory 52 or the HDD 9, as explained later. The
memory 52 and the HDD 9 are examples of embodiments of a memory
device.
[0051] The display image control device 53 performs scan conversion
by a scan converter from the echo data output from the echo data
processing device 4 to the ultrasound image data. Then, the display
image control device 53 displays the ultrasound image (B-mode
image) on the display device 6 based on the ultrasound image
data.
[0052] The display image control device 53 performs a coordinate
conversion between the coordination system of the ultrasound image
and the coordination system of the medical image other than the
ultrasound image and displays both the ultrasound image and the
medical image of the same cross-section on the display device 6. In
this embodiment, as explained later, the ultrasound image and the
medical image are displayed side-by-side on the display device
6.
[0053] As explained later, the medical image in this embodiment is
an MRI image. The MRI image displayed on the display device 6 is a
deformed MRI image acquired in a deformation calculation device 81,
which will be explained later. The details will be explained later.
The display image control device 53 is one example of embodiments
of a display image device.
[0054] The display device 6 includes a LCD (Liquid Crystal Display)
or a CRT (Cathode Ray Tube). The operation device 7 includes a
keyboard and a pointing device (not illustrated) for an operator to
command or input information.
[0055] The control device 8 includes a CPU (Central Processing
Unit). The control device 8 reads out the control program stored in
the HDD 9 and executes functions at respective devices in the
ultrasound diagnostic apparatus 1.
[0056] The control device 8 includes a deformation calculation
device 81 as shown in FIG. 3. The deformation calculation device 81
performs a deformation calculation for deforming a shape of the
body tissue in either one of the ultrasound image or the MRI image
to a shape of the body tissue of the other image. In this
embodiment, the deformation calculation device 81 performs a
deformation calculation for deforming the shape of a breast in the
MRI image to the shape of a breast in the ultrasound image. The
deformation calculation device 81 is one example of embodiments of
a deformation calculation device.
[0057] Now an operation of the ultrasound diagnostic apparatus 1 is
explained based on a flow chart shown in FIG. 4. First, in step S1,
the ultrasound diagnostic apparatus 1 takes the MRI image data
captured by an MRI apparatus that is not illustrated. The MRI image
data taken in the ultrasound diagnostic apparatus 1 is stored in
the memory 52 or the HDD 9.
[0058] Here, a target body tissue for capturing image is a breast.
When a breast is imaged by the MRI apparatus, a subject P is in the
prone position so that the breast Br hangs as shown in FIG. 5A. On
the other hand, as mentioned later, when a breast is imaged by
ultrasound diagnostic apparatus, the subject P is in the supine
position so that the breast Br is in a shape as if it is squashed
by its weight as shown in FIG. 5B.
[0059] Next in step S2, the deformation calculation device 81
performs a deformation calculation to the MRI image data and
generates the MRI image data that is deformed. In particular, the
deformation calculation device 81 performs a deformation
calculation for deforming the shape of the breast in the MRI image
to the shape of the breast in the ultrasound image using the
particle method or the finite element method. These methods are
used for deformation analysis of an object. Thus, in this
embodiment, the MRI image is one example of embodiments of one
image, and the ultrasound image is one example of embodiments of
the other image.
[0060] Here, it is a condition that the breast sits over the
pectoralis major muscle in the human body, so when a deformation
calculation of the shape of breast is performed by the particle
method or the finite element method, a model that the pectoralis
major muscle is a rigid body and the breast is an
uncompressed-hyperelastic body is assumed. That is, the deformation
of the shape of the uncompressed-hyperelastic body set on the rigid
body is calculated by the particle method or the finite element
method.
[0061] For more detail, the posture at capture of an image of the
subject by the MRI apparatus is the prone position. Therefore, as
the breast in the MRI image, it is assumed that the
uncompressed-hyperelastic body Y sets on the lower surface of the
rigid body X that is in a horizontal position hangs down as shown
in FIG. 6A. On the other hand, the posture at capture of an image
of the subject by the ultrasound diagnostic apparatus is the supine
position. Therefore, as the breast in the ultrasound image, it is
assumed that the uncompressed-hyperelastic body Y sets on the lower
surface of the rigid body X which is in a horizontal position is
pressed by its weight as shown in FIG. 6B. The particle method or
the finite element method calculates the deformation shape of the
uncompressed-hyperelastic body Y changing from the condition that
the uncompressed-hyperelastic body Y hangs down from the lower
surface of rigid body X as shown in FIG. 6A to the condition that
the uncompressed-hyperelastic body Y is pressed by its weight to
the upper surface of the rigid body. That is, the method calculates
to change the shape of the breast in the MRI image to the shape of
the breast in the ultrasound image.
[0062] By the calculation of the deformation of the shape with the
particle method or the finite element method, as shown in FIG. 6A,
deformed shape of the uncompressed-hyperelastic body Y accompanying
the stress change is evaluated in the case that the condition that
the uncompressed-hyperelastic body Y hangs from the lower surface
of the rigid body X is changed to the condition that it is pressed
by its weight to the upper surface of the rigid body X. In such
deformation calculation with the particle method or the finite
element method, the size and direction of relative stress to the
uncompressed-hyperelastic body Y in FIG. 6B is considered under the
condition that the condition shown in FIG. 6A is the initial state.
Concretely, in FIG. 6B with the condition of FIG. 6A as a standard,
the stress F=2W that is two times of gravity (volume force) W is
acted to the uncompressed-hyperelastic body Y in a downward
direction (a direction that the upper surface of the rigid body X
receive the stress in FIG. 6B). Note that the gravity used herein
is a relative gravity when the condition of FIG. 6A is a
standard.
[0063] The deformed MRI image data acquired by the deformation
calculation is stored in the memory 52 or the HDD 9.
[0064] Next in step S3, ultrasound waves are transmitted to the
subject in the supine position by the ultrasound probe 2 and the
echo is received. Then, the display image control device 53
displays the ultrasound image UG at real time about
transmitting/receiving surfaces on the display device 6. Further,
the display image control device 53 displays on the display device
6 the deformed MRI image MG' about an arbitrary cross-section and
the ultrasound image UG side-by-side based on the deformed MRI
image data. Here, only deformed MRI image MG' of the cross-section
which is different from the ultrasound image UG is displayed. In
fact, the deformed MRI image MG' is an image that the subject P is
in the supine position (the condition shown in FIG. 5B).
[0065] Next in step S4, an alignment process of the coordinate
system of the ultrasound image UG and the coordinate system of the
deformed MRI image MG' is performed. Concretely, an operator moves
either one of or both of the cross-section(s) of the ultrasound
image UG and the deformed MRI image MG' comparing the images
displayed on the display device 6, and displays the ultrasound
image UG and the deformed MRI image MG' of the same cross-section.
The shifting of the cross-section of the ultrasound image UG is
performed by changing a position of the ultrasound probe 2. The
shifting of the cross-section of the deformed MRI image is
performed by controlling the operation device 7 to command the
change of the cross-section.
[0066] Whether the cross-sections are the same or not is determined
by the operator by referring characteristic regions. In fact, the
scan plane of ultrasound waves by the ultrasound probe 2 is
parallel to the sliced surface of the MRI image.
[0067] After the ultrasound image UG and the deformed MRI image MG'
about the same cross-section are displayed, the operator inputs a
command that the same cross-section are displayed. Because of this,
a coordinate conversion of the coordinate system of the ultrasound
image UG and of the deformed MRI image MG' are allowed and the
alignment process is completed.
[0068] In step S5 after completing the alignment process in the
step S4, as shown in FIG. 7, the display image control device 53
displays on the display device 6 the deformed MRI image MG' of the
same cross-section of the scan plane of the ultrasound waves by the
ultrasound probe 2 next to the ultrasound image UG of the scan
plane. The display image control device 53 performs the coordinate
conversion of the coordinate system of the ultrasound image UG and
of the deformed MRI image MG' and displays the deformed MRI image
MG' that is the same cross-section of the ultrasound image UG. Here
is the explanation about the coordinate conversion by the display
image control device 53: in this embodiment, the position
information of the echo data which is the coordinate system of the
ultrasound image UG is converted to the coordinate system of the
deformed MRI image MG'. Then, the display image control device 53
displays the deformed MRI image MG' about the certain cross-section
acquired from the coordinate conversion. Even if the scan plane of
the ultrasound waves by the ultrasound probe 2 is changed, the
display image control device 53 displays the deformed MRI image
about a cross-section that is newly captured. Therefore, even if
the ultrasound probe 2 is moved and the cross-section of the
ultrasound image is changed, the deformed MRI image MG' about the
same cross-section is newly captured.
[0069] According to the ultrasound diagnostic apparatus 1 of this
embodiment, the ultrasound image UG and the deformed MRI image MG'
are images of the subject P in the supine position, so the same
images of the same shapes of the breast about the same
cross-section can be displayed. Thus, it is advantageous for
diagnosis.
[0070] Although the shape of the breast in the supine position and
in the prone position is greatly different, the shape of the breast
after deformation can be calculated because the deformation
calculation of the shape of the breast is performed using the
particle method or the finite element method.
[0071] Next, an alternative example of the first embodiment is
explained. In the foregoing embodiment, transmitting/receiving of
ultrasound waves was performed to the subject in the supine
position, but when it is performed to the subject in the standing
position, it is assumed that the breast is the
uncompressed-hyperelastic body Y sets on one surface of the rigid
body X in a vertical position as shown in FIG. 8. Then, deformation
of the uncompressed-hyperelastic body Y in the condition shown in
FIG. 6A is changed to the condition shown in FIG. 8 is calculated
by the particle method or the finite element method. In this case,
as the stress for performing the deformation calculation, the
stress of the condition shown in FIG. 8 is considered in a case
that the condition shown in FIG. 6A is an initial condition. That
is, as the stress, the gravity (volume force) W in
vertically-downward direction (a direction parallel to the rigid
body X in FIG. 8) and the gravity (volume force) W in parallel
direction to the rigid body X (a direction which is pressed to one
surface of the rigid body X in FIG. 8) are considered. Also, note
that the gravity used herein is a relative gravity when the
condition of FIG. 6A is a standard.
Second Embodiment
[0072] Next, a second embodiment will be explained. In the
foregoing first embodiment, the real-time ultrasound image UG and
the deformed MRI image having the same cross-section of the
ultrasound image UG are displayed. However, in the second
embodiment, the deformation calculation is performed with raw data
stored in the HDD 9 or the memory 52 to generate deformed echo
data. Then, the deformed ultrasound image UG' based on the deformed
echo data and the MRI image MG based on the MRI image data are
displayed on the display device 6.
[0073] It is concretely explained on the basis of the flow chart in
FIG. 9. In step S11 of FIG. 9, like the step S1 of the first
embodiment, the MRI image data is taken to the ultrasound
diagnostic apparatus 1 and stored in the memory 52 or the HDD
9.
[0074] Next in step S12, transmitting/receiving of the ultrasound
waves to the subject by the ultrasound probe 2 is performed to
capture the echo data. In this step S12, the ultrasound probe 2
scans the three-dimensional region to capture three-dimensional
echo data (volume data). The captured echo data is stored in the
memory 52 or the HDD 9 as raw data.
[0075] Next in step S13, the deformation calculation is performed
by the deformation calculation device 81 for the three-dimensional
echo data captured in the step S12 and the deformed echo data is
generated. The deformation calculation is performed on respective
cross-sections of the three-dimensional echo data.
[0076] In the deformation calculation in this step S13, it is
assumed that the pectoralis major muscle is a rigid body and the
breast is an uncompressed-hyperelastic body. And the deformation
calculation using the particle method or the finite element method
is performed to the deformation of the uncompressed-hyperelastic
body. However in this embodiment, the deformation of the
uncompressed-hyperelastic body Y in the case of change from the
condition that the uncompressed-hyperelastic body Y is pressed by
its weight to the upper surface of the rigid body, as shown in FIG.
10A to the condition that the uncompressed-hyperelastic body Y
hangs down from the lower surface of rigid body X as shown in FIG.
10B by calculating with a particle method or a finite element
method. Then, a calculation is performed to change the shape of the
breast in the ultrasound image to the shape of the breast in the
MRI image. In this embodiment, in the deformation calculation, the
size and direction of the stress applied to the
uncompressed-hyperelastic body Y in FIG. 10B is considered under
the condition that the condition shown in FIG. 10A is an initial
state. Concretely, in FIG. 10B with the condition of FIG. 10A as a
standard, the stress F=2W that is two times of gravity (volume
force) W is acted to the uncompressed-hyperelastic body Y in a
vertical and downward direction (a direction that the upper surface
of the rigid body X receive the stress in FIG. 10B). Note that the
gravity used herein is a relative gravity when the condition of
FIG. 10A is a standard.
[0077] The deformed echo data acquired by the deformation
calculation is stored in the memory 52 or the HDD 9.
[0078] Next in step S14, the display image control 53 displays the
deformed ultrasound image UG' based on the deformed echo data and
the MRI image MG based on the MRI image data side-by-side. Here,
the cross-sections of the deformed ultrasound image UG' and the MRI
image MG are different. The deformed ultrasound image UG' is an
image of the subject P in the prone position (position shown in
FIG. 5A).
[0079] Next in step S15, the alignment process of the coordinate
system of the deformed ultrasound image UG' and the coordinate
system of the MRI image MG is performed. Particularly, this
alignment process is the same as the process of the step S4 in the
first embodiment and it is processed by comparing the deformed
ultrasound image UG' and the MRI image MG displaying the same
cross-section. In fact, the shifting of the cross-section of the
deformed ultrasound image UG' is done by inputting a command to
change the cross-section by operating the operation device 7 as it
is done to the move of the cross-section of the MRI image.
[0080] In step S16, after completing the alignment process in the
step S15, the display image control device 53, as shown in FIG. 11,
displays on the display device 6 the deformed ultrasound image UG'
and the MRI image MG about the same cross-section. In this step
S16, by the command from the operation device 7, even if either of
the cross-sections of the deformed ultrasound image UG' and the MRI
image MG is changed, the display image control device 53 converts
the coordinate system of the image where the cross-section is
changed to the coordinate system of the image where the
cross-section is not changed so that the deformed ultrasound image
UG' and the MRI image MG about the same cross-section are
displayed. For example, when the cross-section of the deformed
ultrasound image UG' is changed, a coordinate of newly acquired
cross-section in the coordinate system of the deformed ultrasound
image UG' is converted to the coordinate system of the MRI image
MG, then the cross-section corresponding to the coordinate system
of the MRI image MG is identified and the MRI image having the same
cross-section as the renewed cross-section is displayed. Also, when
the cross-section of the MRI image MG is changed, a coordinate of
newly acquired cross-section in the coordinate system of the MRI
image MG is converted to the coordinate system of the deformed
ultrasound image UG', then the cross-section corresponding to the
coordinate system of the deformed ultrasound image UG' is
identified and the deformed ultrasound image UG' about the
cross-section which is the same cross-section as the renewed
cross-section is displayed.
[0081] According to the second embodiment described above, the
deformed ultrasound image UG' and the MRI image MG are images of
the subject P is in the prone position, so the same images of the
same shapes of the breast about the same cross-section can be
displayed, as in the first embodiment. Thus, it is advantageous for
diagnosis.
[0082] In the second embodiment, instead of the ultrasound image,
the deformed MRI image acquired by deforming the shape of the
breast in the MRI image to the shape of breast in the ultrasound
image, can be displayed with the ultrasound image.
[0083] The invention was explained with above-mentioned
embodiments, but it will be understood that the invention can be
modified in various ways without departing from the spirit and
scope of the invention. For example, the medical image is not
limited to the MRI image and an X-ray CT image or an image captured
by mammography, for example, can be modified.
[0084] Further, in the second embodiment, instead of the
deformation calculation subject to the raw data which is the echo
data before scan conversion by a scan converter in the display
image control device 53, the deformation calculation can be applied
to the ultrasound image data after scan conversion.
[0085] In the step S5 of the first embodiment, the display image
control device 53 displays the ultrasound image UG and the deformed
MRI image MG' at the same cross-section side-by-side, but as shown
in FIG. 12, the ultrasound image UG and the deformed MRI image MG'
at the same cross-section can be overlaid (or synthesized) and
displayed as transparent images.
[0086] Similarly in step S16 of the second embodiment, the display
image control device 53 displays the deformed ultrasound image UG'
and the deformed MRI image MG at the same cross-section
side-by-side, but as shown in FIG. 13, the deformed ultrasound
image UG' and the deformed MRI image MG at the same cross-section
can be overlaid (or synthesized) and displayed as transparent
images.
[0087] Many widely different embodiments of the invention may be
configured without departing from the spirit and the scope of the
present invention. It should be understood that the present
invention is not limited to the specific embodiments described in
the specification, except as defined in the appended claims.
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