JP2019069319A - Hardness deriving apparatus, medical imaging system, hardness deriving method, and hardness deriving program - Google Patents

Abstract

To provide a hardness deriving apparatus, a medical imaging system, a hardness deriving method, and a hardness deriving program capable of stably measuring the hardness of breast tissue.SOLUTION: The hardness deriving apparatus comprises: a radiographic image acquisition unit for acquiring a radiographic image of a breast pressed by a first pressing pressure with a pressing member; an ultrasound image acquisition unit for acquiring a plurality of ultrasound images, the plurality of ultrasound images including: a first ultrasound image of the breast ultrasonographically captured while the first pressing pressure on the breast with the pressing member is maintained; and a second ultrasound image of the breast ultrasonographically captured while the breast is pressed by a second pressing pressure different from the first pressing pressure with the pressing member; and a deriving unit for determining an amount of change at corresponding points between the plurality of ultrasound images using the plurality of ultrasound images acquired by the ultrasound image acquisition unit, and deriving information indicating the hardness of the breast tissue based on the amount of change at the corresponding points.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a hardness deriving device, a medical imaging system, a hardness deriving method, and a hardness deriving program.

  There is known an ultrasound imaging apparatus for capturing an ultrasound image of a breast by scanning the breast with ultrasound for use in observation and diagnosis of breast tissue. Elastography is known as a technique for detecting the hardness of breast tissue using this ultrasound image.

  Generally, when an ultrasound image of the breast is to be captured by an ultrasound imaging apparatus, the operator moves the ultrasound probe on the surface of the subject's breast, and presses the breast with the ultrasound probe to perform imaging.

  Generally, in elastography, depending on the operator or the procedure, the degree of compression of the breast may differ, and the detection result of elastography, that is, the detection result of the firmness of the breast may not be stably obtained. is there.

  As a technique for performing elastography without using an operator, Patent Document 1 performs elastography automatically by capturing an ultrasonic image by scanning the ultrasound probe in a state where the breast is lightly compressed by the paddle. The technology is described.

Japanese Patent Application Publication No. 2013-530394

  However, as in the technique described in Patent Document 1, it is possible to make the compression condition of the breast constant regardless of the operator by performing elastography in a state in which the breast is lightly compressed, but the Patent Document 1 In the technique described in, in order to detect the relative hardness of breast tissue, a technique capable of stably measuring the hardness of breast tissue is desired.

  The present invention has been made in consideration of the above facts, and it is possible to stably measure the hardness of breast tissue, a hardness deriving device, a medical imaging system, a hardness deriving method, and a hardness It aims to provide a derivation program.

  In order to achieve the above object, the hardness deriving device of the present disclosure comprises a radiation image acquisition unit for acquiring a radiation image of a breast compressed by a compression pressure by a compression member, and a breast at a first compression pressure by the compression member. With the first ultrasound image of the ultrasound-captured breast and the second compression pressure different from the first compression pressure, while maintaining the compression of the breast, the ultrasound image of the breast being ultrasound-captured with the compression member pressing the breast An ultrasound image acquisition unit for acquiring a plurality of ultrasound images including a second ultrasound image, and corresponding points between the plurality of ultrasound images using the plurality of ultrasound images acquired by the ultrasound image acquisition unit And a derivation unit for obtaining the amount of change and for deriving information indicating the hardness of the breast tissue based on the amount of change in the corresponding points.

  In the derivation unit of the hardness derivation device of the present disclosure, the derivation unit is a corresponding point with the pixels of the corresponding part of the breast in each of the plurality of ultrasonic images acquired by the ultrasonic image acquisition unit as corresponding points. Information indicating hardness of breast tissue may be derived based on the amount of change in pixel value of the pixel.

  The derivation unit of the hardness derivation device of the present disclosure uses the pixels of the corresponding portion of the breast as the corresponding points in each of the plurality of ultrasonic images acquired by the ultrasonic image acquisition unit, Information indicating hardness of breast tissue may be derived based on the amount of change.

  The hardness deriving device of the present disclosure may further include a display control unit for performing control to cause the display unit to display an elastography image obtained using a color corresponding to the hardness indicated by the information derived by the deriving unit. .

  The acquisition unit of the hardness deriving device of the present disclosure further acquires a radiation image taken by irradiating radiation to the breast in a state where the breast is compressed by the compression member, and the display control unit includes the radiation image and the elastography image And may be displayed side by side or overlapping on the display unit.

  In addition, the hardness deriving device of the present disclosure further includes an object of interest receiving unit that receives specification of an object of interest in any one of a radiation image and an elastography image displayed on the display unit, and the display control unit The position of the object region received by the object region receiving unit is detected from the image in which the object region is specified among the image and the elastography image, and the detected object region in the image in which the object region is not specified Control may be performed to display information representing the position corresponding to the position.

  The ultrasound image acquisition unit of the hardness deriving device of the present disclosure performs ultrasound scanning of the breast in a state in which the breast is compressed by each of the plurality of pressures including the first compression pressure and the second compression pressure by the compression member. A plurality of ultrasound images are acquired from an ultrasound imaging apparatus that performs ultrasound imaging of the breast, and the display control unit causes the display unit to display a radiation image, and the radiation image displayed on the display unit The system further includes an object of interest image reception unit for receiving an instruction, and the position of the image of interest received by the object of interest image reception unit is detected from the radiation image, and ultrasound is detected at a position corresponding to the position of the image of the detected object of interest. The imaging control unit may be provided to control the ultrasonic imaging apparatus to make the scanning speed slower than other positions.

  The ultrasound image acquisition unit of the hardness deriving device of the present disclosure performs ultrasound scanning of the breast in a state in which the breast is compressed by each of the plurality of pressures including the first compression pressure and the second compression pressure by the compression member. A plurality of ultrasound images are acquired from an ultrasound imaging apparatus that performs ultrasound imaging of the breast, the position of the image of the object of interest is detected from the radiation image, and the position corresponding to the position of the image of the object of interest is detected. The imaging control unit may be provided to control the ultrasound imaging apparatus to make the speed at which the sound wave is scanned slower than other positions.

  The ultrasound image acquisition unit of the hardness deriving device of the present disclosure performs ultrasound scanning of the breast in a state in which the breast is compressed by each of the plurality of pressures including the first compression pressure and the second compression pressure by the compression member. A plurality of ultrasound images are acquired from an ultrasound imaging apparatus that performs ultrasound imaging of the breast, and at the position of the object of interest corresponding to the object of interest included in the breast, the speed at which the ultrasound is scanned is The imaging control unit may be provided to perform control to delay the ultrasound imaging apparatus.

  In the hardness deriving device of the present disclosure, when the hardness represented by the information derived by the deriving unit is harder than the threshold hardness, the display of the information indicating the position of the breast tissue harder than the threshold hardness is displayed. And a warning unit for giving a warning.

  The hardness deriving device of the present disclosure further includes a hardness receiving unit that receives setting of a hardness serving as a threshold, and the warning unit detects the position of a breast tissue that is harder than the hardness serving as the threshold received by the hardness receiving unit. Display and warning of information may be performed.

  In order to achieve the above object, the medical imaging system of the present disclosure uses ultrasound to scan a breast while compressing the breast with each of a plurality of pressures including a first compression pressure and a second compression pressure by the compression member. An ultrasound imaging apparatus that performs ultrasound imaging of a breast and outputs a plurality of captured ultrasound images, and an acquisition unit that acquires a plurality of ultrasound images output from the ultrasound imaging apparatus. And a hardness deriving device.

  In order to achieve the above object, the hardness deriving method of the present disclosure acquires a radiation image of a breast compressed by a first compression pressure by a compression member and maintains compression of the breast at a first compression pressure by the compression member. As it was, with the first ultrasound image of the ultrasound-captured breast and the second ultrasound image of the ultrasound-captured breast in a state where the breast was compressed by the compression member with a second compression pressure different from the first compression pressure And a plurality of ultrasound images including the plurality of ultrasound images are used to determine the amount of change in corresponding points between the plurality of ultrasound images, and based on the amount of change in corresponding points, breast tissue A method for causing a computer to execute a process including deriving information indicating hardness of

  In order to achieve the above object, the hardness deriving program of the present disclosure acquires a radiation image of a breast compressed by a first compression pressure by the compression member and maintains compression of the breast at the first compression pressure by the compression member. As it was, with the first ultrasound image of the ultrasound-captured breast and the second ultrasound image of the ultrasound-captured breast in a state where the breast was compressed by the compression member with a second compression pressure different from the first compression pressure And a plurality of ultrasound images including the plurality of ultrasound images are used to determine the amount of change in corresponding points between the plurality of ultrasound images, and based on the amount of change in corresponding points, breast tissue For causing a computer to execute processing including deriving information indicating hardness of

  The present invention can provide a hardness deriving device, a medical imaging system, a hardness deriving method, and a hardness deriving program that can stably measure the hardness of breast tissue.

It is a block diagram showing composition of a medical imaging device and a console in a medical imaging system of a 1st embodiment. It is a side view which shows the external appearance of the imaging part of the medical imaging device of 1st Embodiment. It is a figure explaining the case where imaging | photography of the radiographic image in continuous imaging | photography mode is performed in the medical imaging device of 1st Embodiment. 5 is a flowchart showing an overall flow of imaging operations in a continuous imaging mode in which imaging of a radiation image and an ultrasonic image is continuously performed by the medical imaging apparatus of the first embodiment. It is a figure explaining the case where imaging | photography of an ultrasound image is performed in the medical imaging device of 1st Embodiment. It is a flowchart showing the flow of the image display process by the console of 1st Embodiment. It is a schematic diagram which shows an example of a display in the case of displaying a radiographic image and an elastography image side by side, when not displaying the warning in 1st Embodiment. It is a schematic diagram which shows an example of a display in the case of displaying a radiographic image and an elastography image side by side in the case of displaying the warning in 1st Embodiment. It is a schematic diagram which shows an example of a display in the case of making a radiographic image and an elastography image overlap, and displaying in 1st Embodiment. In 1st Embodiment, it is a schematic diagram which shows an example of the state which designated the region of interest including a target object image using a mouse pointer as an example in the case of specifying the target object image in a radiographic image. In an example shown in Drawing 7, it is a mimetic diagram showing an example of a display of a position in an elastography image corresponding to an object-of-interest picture specified by a user. FIG. 12 is a schematic view showing an example in the case of displaying a B-mode image at different positions in the example shown in FIG. 11; 9 is a flowchart showing an overall flow of imaging operations in a continuous imaging mode in which imaging of a radiation image and an ultrasonic image is continuously performed by the medical imaging apparatus of the second embodiment. In 2nd Embodiment, the control part of a console is a schematic diagram which shows an example of a display of the radiographic image acquired from the medical imaging device. In 2nd Embodiment, it is a schematic diagram for demonstrating the method to determine the position which changes the scanning speed in a compression board upper surface from a radiographic image.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present embodiment does not limit the present invention.
First Embodiment
As shown in FIG. 1, the medical imaging system 1 of the present embodiment includes a medical imaging apparatus 10 and a console 50.

  The medical imaging apparatus 10 according to the present embodiment irradiates radiation R to the breast of the subject and detects the radiation R transmitted through the breast. The function of the mammography apparatus for capturing a radiation image and transmission of ultrasound to the breast And an ultrasound imaging apparatus for capturing an ultrasound image by receiving the ultrasound echo reflected inside the breast.

  In addition, there are two types of imaging of ultrasonic images in the medical imaging apparatus 10 of the present embodiment: imaging of normal ultrasonic images (details will be described later) and imaging of ultrasonic images for elastography. In the present embodiment, “elastography” refers to detection of the hardness of breast tissue, not the entire breast, as the hardness of the breast. In the medical imaging system 1 of the present embodiment, an image (hereinafter, referred to as “elastography image”) representing a result of performing elastography using an ultrasonic image captured by the medical imaging apparatus 10 is presented to the user.

  In the present embodiment, the “user” refers to a person who diagnoses or observes a region of interest in the breast, and the “operator” refers to a person who captures a radiographic image or an ultrasonic image. . The “user” and the “operator” may be the same person or different persons.

  The configuration of the medical imaging apparatus 10 according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 2, the medical imaging apparatus 10 of the present embodiment includes an arm unit 20, a base 22, and a shaft unit 24. The base 22 holds the arm unit 20 so as to be movable in the vertical direction (Z-axis direction). The shaft 24 connects the arm 20 to the base 22. The arm portion 20 is rotatable relative to the base 22 with the shaft portion 24 as a rotation axis.

  The arm unit 20 is provided with a radiation emission unit 25, an imaging stand 31, and a compression unit 21.

  The radiation emitting unit 25 includes a radiation tube 26, a filter 28, and a high voltage generating unit 29. The radiation tube 26 generates a radiation R when a tube voltage is applied. The filter 28 is made of a material such as molybdenum (Mo) or rhodium (Rh) and selectively transmits a desired wavelength component from among a plurality of wavelength components included in the radiation R generated by the radiation tube 26. .

  When imaging is performed, the breast of the subject is positioned on the imaging table 31. The imaging base 31 or the like in contact with the breast of the subject is formed of, for example, carbon from the viewpoint of the permeability and intensity of the radiation R. A radiation detector 30 for detecting radiation R transmitted through the breast and the imaging table 31 is disposed inside the imaging table 31. A radiation image is generated based on the radiation R detected by the radiation detector 30. The type of radiation detector 30 according to the present embodiment is not particularly limited. For example, the radiation detector may be an indirect conversion radiation detector that converts radiation R into light and converts the converted light into electric charge. The radiation detector may be a direct conversion type radiation detector that converts the light into a direct charge.

  The compression unit 21 is provided with a compression plate 32, a compression plate moving mechanism 34, an ultrasonic probe 36, and a probe moving mechanism 38. The compression unit 21 and the arm unit 20 can be separately rotated relative to the base 22 with the shaft unit 24 as a rotation axis. In the present embodiment, gears are provided to the shaft 24, the arm 20, and the compression unit 21, respectively, and by switching the meshing state / non-meshing state of the gears, each of the arm 20 and the compression unit 21 is an axis. It is connected to the part 24. One or both of the arm unit 20 and the compression unit 21 connected to the shaft 24 rotate integrally with the shaft 24.

  The compression plate 32 is moved in the vertical direction (Z-axis direction) by the compression plate moving mechanism 34 to compress the subject's breast with the imaging table 31. The compression plate 32 is preferably optically transparent in order to confirm the alignment and the compression state in the compression of the breast, and the transmission of the radiation R in order to easily transmit the radiation R emitted from the radiation emission unit 25 It is formed of an excellent material. In addition, the compression plate 32 is preferably formed of a material that easily transmits the ultrasonic wave transmitted from the ultrasonic probe 36. As a material of the compression board 32, resin, such as polymethyl pentene, a polycarbonate, an acryl, and a polyethylene terephthalate, can be used, for example. In particular, polymethylpentene has a low rigidity and is excellent in stretchability and flexibility, and has a suitable value in terms of acoustic impedance that affects the reflectance of ultrasonic waves and the attenuation coefficient that affects the attenuation of ultrasonic waves. It is suitable as a material of the plate 32.

  The ultrasonic probe 36 is moved along the upper surface of the compression plate 32 (the surface opposite to the side on which the patient's breast is placed) by the probe moving mechanism 38, and the breast is scanned with ultrasound. Acquire an ultrasound image. The ultrasound probe 36 includes a plurality of ultrasound transducers (not shown) arranged in a one-dimensional manner or a two-dimensional manner. Each ultrasonic transducer transmits an ultrasonic wave based on an applied drive signal and outputs a reception signal by receiving an ultrasonic echo.

Each of the plurality of ultrasonic transducers is, for example, a piezoelectric ceramic represented by PZT (lead zirconate titanate: Pb (lead) zirconate titanate), or a polymer piezoelectric represented by PVDF (polyvinylidene fluoride: polyvinylidene fluoride). It is comprised by the vibrator | oscillator which formed the electrode in the both ends of the material (piezoelectric body) which has piezoelectricity, such as an element. When a pulse or continuous wave drive signal is sent to the electrodes of the vibrator to apply a voltage, the piezoelectric body expands and contracts. By this expansion and contraction, pulsed or continuous ultrasonic waves are generated from the respective transducers, and an ultrasonic beam is formed by the synthesis of the ultrasonic waves. In addition, each transducer expands and contracts by receiving propagating ultrasonic waves, and generates an electrical signal. The electrical signals are output as ultrasonic reception signals, and are input to the control unit 40 via a cable (not shown).

  When ultrasonic imaging is performed, the ultrasonic probe 36 is applied to the upper surface of the compression plate 32 in a state where an acoustic matching member (see FIG. 5, details will be described later) such as echo jelly is applied to the upper surface of the compression plate 32. Move along. In the medical imaging apparatus 10 of the present embodiment, the control unit 40 causes the probe moving mechanism 38 to move the ultrasonic probe 36 so that the operator automatically takes an ultrasonic image without moving the ultrasonic probe 36. Do. Note that the present invention is not limited to this embodiment, and the ultrasonic probe 36 may be moved by the operator to take an ultrasonic image.

  Further, as shown in FIG. 1, the medical imaging apparatus 10 according to the present embodiment includes a pressure sensor 33, a position sensor 37, a control unit 40, a storage unit 42, an operation panel 44, and an I / F (InterFace) unit 46. . Radiation emitting unit 25, radiation detector 30, pressure sensor 33, compression plate moving mechanism 34, ultrasonic probe 36, position sensor 37, probe moving mechanism 38, control unit 40, storage unit 42, operation panel 44, and I / F The (InterFace) unit 46 is connected so as to be able to exchange various signals with one another via a bus 49 such as a system bus or a control bus.

  The control unit 40 includes a central processing unit (CPU) 40A, a read only memory (ROM) 40B, and a random access memory (RAM) 40C. Various programs to be executed by the CPU 40A are stored in advance in the ROM 40B. The RAM 40C temporarily stores various data.

  The pressure sensor 33 detects the pressure applied to the compression plate 32. The position sensor 37 is incorporated in the ultrasonic probe 36 and detects the position of the ultrasonic probe 36 (the position on the surface of the compression plate 32).

  The control unit 40 controls the overall operation of the medical imaging apparatus 10. When taking a radiation image, the control unit 40 of the present embodiment controls the radiation emitting unit 25, the radiation detector 30, and the compression plate moving mechanism 34. The control unit 40 causes the compression plate moving mechanism 34 to move the compression plate 32 based on the detection result of the pressure sensor 33 to compress the breast with the imaging table 31. The control unit 40 adjusts the imaging conditions such as the tube voltage and the tube current and applies the high voltage generated by the high voltage generation unit 29 to the radiation tube 26 to emit radiation R from the radiation emission unit 25 . The control unit 40 causes the radiation detector 30 to detect the radiation R transmitted through the breast, thereby capturing a radiation image.

  In addition, when capturing an ultrasound image, the control unit 40 of the present embodiment controls the ultrasound probe 36 and the probe moving mechanism 38 in a state where the breast is pressed by the compression plate 32. The control unit 40 grasps the position of the ultrasonic probe 36 based on the detection result of the position sensor 37 and moves the ultrasonic probe 36 by the probe moving mechanism 38. The control unit 40 captures an ultrasonic image by transmitting and receiving ultrasonic waves while moving the ultrasonic probe 36 by the probe moving mechanism 38. In addition, when capturing an ultrasound image for elastography, the control unit 40 of the present embodiment captures two ultrasound images that have different compression pressures that press the breast with the compression plate 32.

  The storage unit 42 stores image data of a radiation image, an ultrasound image, and an elastography image obtained by imaging, various other information, and the like. Specific examples of the storage unit 42 include a hard disk drive (HDD) and a solid state drive (SSD).

  The operation panel 44 receives an instruction (for example, an instruction to compress a breast by the compression plate 32) by the operator regarding imaging. The operation panel 44 is provided, for example, on the arm unit 20 of the medical imaging apparatus 10. Operation panel 44 may be provided as a touch panel in which a display unit and an input unit are combined.

  The I / F unit 46 communicates various information with the console 50 or an external system (for example, RIS: Radiology Information System) by wireless communication or wire communication. In the medical imaging apparatus 10 according to the present embodiment, the radiographed image and the ultrasound image are transmitted from the I / F unit 46 to an external apparatus such as the console 50 or an image reading apparatus.

  On the other hand, as shown in FIG. 1, the console 50 of the present embodiment includes a control unit 52, a storage unit 54, a display unit 56, an input unit 57, and an I / F unit 58. The control unit 52, the storage unit 54, the display unit 56, the input unit 57, and the I / F unit 58 are connected to each other to be able to transmit and receive various signals via a bus 59 such as a system bus or a control bus.

  The control unit 52 includes a CPU 52A, a ROM 52B, and a RAM 52C. The ROM 52B stores in advance various programs including a hardness deriving program executed by the CPU 52A. The RAM 52C temporarily stores various data.

  The control unit 52 controls the overall operation of the console 50. The control unit 52 of the present embodiment instructs the medical imaging apparatus 10 to capture a radiation image and capture an ultrasound image based on the imaging menu.

  Further, the control unit 52 of the present embodiment performs control to display the radiation image and the ultrasound image obtained by the medical imaging apparatus 10 on the display unit 56. Furthermore, the control unit 52 generates an elastography image from the ultrasound image obtained by the medical imaging apparatus 10, and performs control to display the generated elastography image on the display unit 56.

  The storage unit 54 stores image data of each of a radiation image, an ultrasound image, and an elastography image obtained by the medical imaging apparatus 10, various other information, and the like. Examples of the storage unit 54 include an HDD and an SSD.

  The display unit 56 displays information on radiography and ultrasound imaging. Further, the display unit 56 displays a radiation image, an ultrasound image and an elastography image.

  The input unit 57 receives an instruction on imaging by an operator who performs imaging of a radiation image or an ultrasound image, and an instruction on display of a radiation image, an ultrasound image, and an elastography image by an operator or a user. The console 50 may include a touch panel in which the display unit 56 and the input unit 57 are combined.

  The I / F unit 58 communicates various information with the medical imaging apparatus 10 or an external system such as RIS by wireless communication or wire communication.

  Next, imaging of a radiation image and an ultrasound image in the medical imaging apparatus 10 of the present embodiment will be described.

  In the medical imaging apparatus 10 of the present embodiment, any one of an imaging mode (hereinafter referred to as a “continuous imaging mode”) for continuously imaging a radiation image and an ultrasound image, and imaging of a radiation image or imaging of an ultrasound image And shooting mode. Hereinafter, a case where the medical imaging apparatus 10 executes the continuous imaging mode will be described. In addition, as described above, in the imaging of ultrasonic images in the continuous imaging mode performed by the medical imaging apparatus 10 according to the present embodiment, the imaging of a normal ultrasonic image and the imaging of an ultrasonic image for elastography, 2 There is a kind of shooting.

  In the medical imaging apparatus 10 of the present embodiment, when capturing an ultrasound image of the breast in a state of being compressed by the compression plate 32, in order to reduce the mismatch of the impedance of the ultrasonic wave at the contact surface between the compression plate 32 and the breast. An acoustic matching member is provided between the compression plate 32 and the breast. When the continuous imaging mode is executed in the medical imaging apparatus 10 of the present embodiment, the imaging of the radiographic image and the imaging of the ultrasonic image are completed by the compression plate 32 without releasing the compression of the breast of the radiographic image and the ultrasonic image. Since both imagings are continuously performed with the breast being compressed until the radiological image is taken, as shown in FIG. 3 as an example, the acoustic matching member 60 which is unnecessary for radiological image imaging squeezes It is provided between the board 32 and the breast N.

  The acoustic matching member 60 provided between the compression plate 32 and the breast N in the medical imaging apparatus 10 of the present embodiment has both the compatibility with the living body (the breast N in the present embodiment) and the permeability of ultrasonic waves. It is made of good material. The acoustic matching member 60 is preferably made of a material that is flexible, has physical strength, is ultrasonic-transparent, and can withstand sterilization. As a material of the acoustic matching member 60, non-hydrogel materials such as urethane rubber and silicone rubber, and polymer hydrogels such as polyvinyl alcohol and polyethylene oxide are used. In the medical imaging apparatus 10 of the present embodiment, a so-called gel pad in which the surface of the acoustic matching member 60 is covered with silicone rubber or the like is used as the acoustic matching member 60 in order to maintain the shape.

  In the medical imaging apparatus 10 of the present embodiment, in the case of an imaging mode in which only a radiation image of the breast is taken, the radiation image is taken without providing the acoustic matching member 60 between the compression plate 32 and the breast. It is also good.

  FIG. 4 shows the overall flow of a series of imaging operations when the operator captures a radiographic image and an ultrasonic image in the continuous imaging mode in the medical imaging apparatus 10 (medical imaging system 1) of the present embodiment.

  First, in step S100, the control unit 52 of the console 50 acquires a shooting menu. The imaging menu includes information on imaging conditions, subjects, breast N and the like, and information on whether or not to perform ultrasound imaging for elastography. For example, the control unit 52 may obtain a shooting menu from an external system or the like via the I / F unit 58, or may obtain a shooting menu input by the operator from the input unit 57.

  In the next step S102, the operator positions the breast N of the subject on the imaging table 31.

  Then, in the next step S104, the control unit 40 of the medical imaging apparatus 10 squeezes the breast N of the subject with the compression plate 32 in a state where the acoustic matching member 60 is provided on the upper surface (a surface on the compression plate 32 side) of the breast N Do. Specifically, when the positioning is finished, the operator performs an instruction input for moving the compression plate 32 from the operation panel 44. The control unit 40 moves the compression plate 32 in the direction approaching the imaging table 31 by the compression plate moving mechanism 34 according to the instruction input of the operator, thereby sandwiching the acoustic matching member 60 with the breast N. Squeeze the breast N. In addition, compression of the breast N in this step is performed in order to reduce the exposure dose while spreading the breast N to make the breast N uniform thickness in order to separate the overlap of mammary gland tissue in radiographing. The pressure is applied according to the condition of the subject, the breast N, and the like.

  When the breast N is compressed by the compression plate 32, the method of providing the acoustic matching member 60 on the upper surface of the breast N is not particularly limited. The acoustic matching member 60 may be attached to the surface of the compression plate 32 on the breast side, and the breast N may be compressed by the compression plate 32 in a state where the acoustic matching member 60 is attached to the compression plate 32. The breast N may be compressed by the compression plate 32 in a state where the operator places the acoustic matching member 60 on the breast N.

  In the next step S106, the medical imaging apparatus 10 captures a radiation image of the breast N. When a radiation image is taken, the control unit 40 causes the probe moving mechanism 38 to retract the ultrasonic probe 36 outside the detection region of the radiation image by the radiation detector 30. Image data of the radiographed radiation image is output to the console 50. The image data of the radiation image may be immediately output to the console 50 after the radiation image is captured, or may be stored at one end in the storage unit 42, and after the radiation image and the ultrasound image have been captured, both may be stored. Image data of an image may be output to the console 50.

  After the radiation image is taken, the operator applies the echo jelly 62 to the upper surface (the surface opposite to the side on which the breast N is disposed) of the compression plate 32 in the next step S108, as shown in FIG. 5 as an example. Do. The echo jelly 62 is also an acoustic matching member. As the echo jelly 62, for example, distilled water, moisturizing agent (at least one of propylene and glycol), high-molecular polymer, soluble lanolin, coloring agent, flavor, and preservative (at least one of propylparaben and antibacterial methylparaben) And a gynecological low viscosity gel having a pH value of 6.5 to 7.0 and a viscosity of 25,000 CPS to 45,000 CPS.

  In the next step S110, the control unit 40 of the medical imaging apparatus 10 determines whether or not to perform ultrasound imaging for elastography. In the medical imaging apparatus 10 according to the present embodiment, imaging of an ultrasound image for elastography is performed based on the information regarding whether or not the imaging of the ultrasound image for elastography is included in the imaging menu acquired in step S100. To determine whether to

  When the application of the echo jelly 62 is completed, the operator performs an instruction input for instructing imaging of an ultrasonic image from the operation panel 44. When the control unit 40 detects an instruction input of the operator, the control unit 40 executes this step. If a normal ultrasound image is to be captured, the determination is negative and the process proceeds to step S112.

  After capturing a normal ultrasonic image in step S112, the medical imaging apparatus 10 proceeds to step S122. In the present embodiment, the “normal ultrasound image” refers to an ultrasound image captured without adjusting the pressure applied to the breast N by the compression plate 32 for elastography. A normal ultrasound image is an ultrasound image used for general diagnosis, observation, etc., and refers to, for example, an ultrasound image in B (brightness) mode or the like.

  Here, as described above, while the control unit 40 detects the position of the ultrasonic probe 36 by the position sensor 37, the control unit 40 is along the surface (surface facing the radiation tube 26) on which the echo jelly 62 is applied. Then, the ultrasonic probe 36 is moved by the probe moving mechanism 38. Then, the control unit 40 transmits an ultrasonic wave from the ultrasonic probe 36 to the breast N, and captures an ultrasonic image by receiving an ultrasonic echo reflected inside the breast N.

  On the other hand, in the case where imaging for elastography is performed in step S110, a positive determination is made, and the process proceeds to step S114.

  In step S114, the medical imaging apparatus 10 compresses the breast N with a first predetermined compression pressure. Specifically, the control unit 40 causes the compression plate moving mechanism 34 to move the compression plate 32 in the direction approaching or away from the imaging table 31 so that the detection result of the pressure sensor 33 becomes the first compression pressure. .

  Then, in the next step S116, the medical imaging apparatus 10 captures an ultrasound image. The method of capturing an ultrasonic image may be the same as in the above step S112, or may be different, for example, by making the moving speed for moving the ultrasonic probe 36 by the probe moving mechanism 38 different from that in the case of step S112. Good. Hereinafter, an ultrasonic image captured in a state in which the breast N is compressed by the first compression pressure is referred to as a "first ultrasonic image". In addition, an ultrasonic image taken in a state where the breast N is compressed by a second compression pressure, which will be described in detail later, is referred to as a "second ultrasonic image". Moreover, when naming a 1st ultrasound image and a 2nd ultrasound image generically, it is only called an "ultrasound image."

  In the next step S118, the medical imaging apparatus 10 compresses the breast N with a predetermined second compression pressure. Specifically, the control unit 40 moves the compression plate 32 in the direction approaching the imaging table 31 by the compression plate moving mechanism 34, and sets the detection result of the pressure sensor 33 to the second compression pressure. In the present embodiment, the second compression pressure is higher than the first compression pressure (first compression pressure <second compression pressure).

  Unlike the present embodiment, when the first compression pressure is higher than the second compression pressure, the compression pressure is changed from the first compression pressure to the second compression pressure, whereby the breast by the compression plate 32 and the imaging platform 31 Tightening to the loose. In this case, loose tightening may cause body movement of the subject. Therefore, in the medical imaging apparatus 10 of the present embodiment, the second compression pressure is higher than the first compression pressure. In this case, changing the compression pressure from the first compression pressure to the second compression pressure makes it difficult to tighten the breast by the compression plate 32 and the imaging table 31. In the case where tightening becomes tight is less likely to cause body movement of the subject than in the case where tightening becomes loose. When body movement of the subject occurs, a change occurs in the position, shape, etc. of the breast N between the first ultrasound image captured in step S116 and the second ultrasound image captured in step S120 described later As a result, the detection accuracy of the hardness of the tissue of the breast N is reduced. Therefore, in the present embodiment, the second compression pressure is set higher than the first compression pressure in order to suppress body movement of the subject.

  The specific pressure of the first compression pressure and the second compression pressure is not particularly limited as long as the second compression pressure is higher than the first compression pressure as described above. For example, one of the first compression pressure and the second compression pressure may be the same as the compression pressure at which the breast N is compressed at step S104. As described above, from the viewpoint of suppressing the body movement of the subject, it is preferable to make the first compression pressure the same as the compression pressure that squeezed the breast N in step S104. If the first compression pressure is the same as the compression pressure of the breast N compressed in step S104, the control unit 40 may not perform the process of step S114.

  In addition, the specific first compression pressure and the second compression pressure, or the difference between the second compression pressure and the first compression pressure, changes in the body movement of the subject, the shape of the breast N, and the like, and the tissue of the breast N It may be predetermined in the apparatus based on the viewpoint of derivation of the hardness of

  In the next step S120, the medical imaging apparatus 10 captures a second ultrasound image as in step S116.

  When the imaging of the ultrasound image is completed as described above, the process proceeds to step S122. The image data of each captured ultrasonic image is output to the console 50. The image data of each ultrasound image may be output to the console 50 immediately after the imaging of each ultrasound image, or may be stored in the storage unit 42 at one end, for capturing a radiation image and each ultrasound image. After the end, the image data of these images may be output to the console 50.

  In step S122, the medical imaging apparatus 10 releases the compression of the breast N by the compression plate 32. Specifically, the operator performs an instruction input (an instruction input for releasing the compression) for moving the compression plate 32 via the operation panel 44. The control unit 40 releases the compression of the breast N by moving the compression plate 32 in the direction away from the imaging table 31 by the compression plate moving mechanism 34 according to the instruction input of the operator.

  Thus, when the compression of the breast N is released, the imaging operation in the continuous imaging mode ends. The console 50 acquires the image data of the radiation image output from the medical imaging apparatus 10 and the image data of the normal ultrasound image or the first ultrasound image and the second ultrasound image, and stores them in the storage unit 54. Let

  The console 50 executes an image display process for displaying a radiation image, a normal ultrasound image, and an elastography image on the display unit 56 in accordance with a user's instruction. Hereinafter, when a radiographic image, an ultrasound image, and an elastography image are collectively referred to, they are simply referred to as an “image”. FIG. 6 is a flowchart showing the flow of the image display process executed by the console of this embodiment.

  The image display process shown in FIG. 6 is executed when an instruction to display an image is issued from the user via the input unit 57.

  In step S200, the control unit 52 determines whether the type of the image to be displayed has been accepted. Specifically, it is determined whether or not the user has accepted an instruction of the type of the image to be displayed, which has been made via the input unit 57. The determination is negative until the type of the image is received, and the standby state is established. On the other hand, when the type of the image is received, the determination is positive and the process proceeds to step S202. In the case where a plurality of images of different imaging times, subjects, or images of different breasts, for example, are stored in the storage unit 54 for the same type of image, the user is any image in addition to the type of image. The user designates an image to be displayed by instructing information (for example, identification information (ID: Identification) of the image, identification information of the subject W, etc.) for identifying the image via the input unit 57.

  In step S202, the control unit 52 determines whether the type of the accepted image includes an elastography image. If the elastography image is not included, the determination is negative and the process proceeds to step S204.

  In step S204, the control unit 52 acquires the received type of image from the storage unit 54, and then proceeds to step S228. As described above, when the information for identifying the image is received, the image corresponding to the received information is acquired.

  On the other hand, in the case where the type of the image accepted in step S202 includes an elastography image, an affirmative determination is made, and the process proceeds to step S206.

  In step S206, the control unit 52 acquires the first ultrasound image and the second ultrasound image from the storage unit 54. As described above, when the information for identifying the image is received, the first ultrasonic image and the second ultrasonic image according to the received information are acquired.

  In the next step S208, the control unit 52 detects corresponding points between the first ultrasound image and the second ultrasound image. The method of detecting the corresponding points is not particularly limited. For example, the positions of the ultrasonic probe 36 and the positions of the pixels of each ultrasonic image are associated and stored in the imaging of the first ultrasonic image and the second ultrasonic image. In the first ultrasonic image and the second ultrasonic image, the position of the corresponding ultrasonic probe 36 is detected from each of the first ultrasonic image and the second ultrasonic image as the corresponding point as a corresponding point You may

  In the next step S210, the control unit 52 derives the variation of the pixel value of each pixel. In the present embodiment, as an example, the control unit 52 subtracts the pixel value of the pixel of the first ultrasound image from the pixel value of the second ultrasound image for each corresponding point (pixel value of the second ultrasound image-first) The amount of change in the pixel value of each pixel is derived by the pixel value of the ultrasound image.

  In the next step S212, the control unit 52 digitizes the hardness of the tissue of the breast N for each pixel. The method of digitizing the hardness is not particularly limited, but the control unit 52 of the present embodiment determines a predetermined constant, the amount of change of the pixel value of each pixel derived in step S210, and the second compression pressure. The definition of the following equation (1), which is obtained using the difference with the first compression pressure, is quantified by applying to each pixel.

Hardness = constant × (amount of change / (second compression pressure−first compression pressure)) (1)
The constant in the above equation (1) is a constant obtained experimentally, and may be determined in advance in the apparatus. Also, the amount of change is smaller as the tissue of breast N is harder and larger as it is softer. Therefore, the numerical value indicating the hardness derived by the above equation (1) indicates that the smaller the value is, the harder, and the larger the value, the softer.

  In the next step S214, the control unit 52 determines the color of each pixel according to the numerical value indicating the hardness of the tissue of the breast N obtained in the above step S212. The console 50 of the present embodiment causes the display unit 56 to display an elastography image using a color according to the hardness of the tissue of the breast N, as in the elastography image obtained by general elastography. In general-purpose elastography, the image is displayed as bluer as it gets harder and as red as it gets softer. Generally, the tissue of breast N is displayed in red because it is softer as the proportion of fat is higher, and it may be soft or slightly hard in benign tumors and mammary glands, and displayed as red or yellow, etc., which is malignant. The tumor is displayed in blue because it tends to be harder as it is a tumor (as so-called breast cancer progresses).

  Therefore, in the console 50 of the present embodiment, the red color is associated as the numerical value obtained in step S212 is larger, and the blue color is associated as the numerical value is smaller, and the correspondence between the numerical value and the color is determined in advance 52 determines the color of each pixel based on the correspondence between the numerical value and the color.

  In the next step 216, the control unit 52 determines whether or not to display a warning. As mentioned above, the harder the tissue, the more likely it is a malignant tumor. Therefore, in the console 50 of the present embodiment, when the numerical value indicating the hardness of the tissue of the breast N is harder than the predetermined hardness, specifically, in step S212, the threshold value is predetermined in each pixel. If the hardness quantified is small, it is likely to be a malignant tumor, and a warning can be displayed. If the number of pixels whose hardness is smaller than a predetermined threshold is more than or equal to a predetermined number or more than a predetermined number, a warning is displayed, and the number of pixels existing in a certain number is predetermined. If the number is less than the predetermined number, the warning may not be displayed.

  In the console 50 of the present embodiment, whether or not to display a warning in this manner may be set in advance, for example, before execution of the present image display processing. Also, for example, even if the control unit 52 performs display on the display unit 56 inquiring whether or not to display a warning, the user may instruct the user via the input unit 57 as to whether to display the warning or not. Good.

  When the warning is not displayed, the determination is negative and the process proceeds to step S224. On the other hand, when displaying a warning, it becomes affirmation determination and transfers to step S218.

  In step S218, the control unit 52 determines whether to set a threshold for displaying the warning described above. In the console 50 of the present embodiment, the user can set a predetermined threshold for displaying a warning. Therefore, it is determined whether the user sets a predetermined threshold. Specifically, the control unit 52 instructs the user via the input unit 57 as to whether or not to set the threshold by performing display on the display unit 56 inquiring whether or not to set the threshold. It is also good.

  When the threshold is not set, the determination is negative and the process proceeds to step S222. When the threshold is not set, a warning is displayed by using a predetermined threshold in the apparatus.

  On the other hand, when setting the threshold value, an affirmative determination is made and the process proceeds to step S220. In step S220, the control unit 52 receives the setting of the threshold set by the user via the input unit 57.

  In the next step S222, the control unit 52 detects a pixel whose numerical value indicating hardness of the tissue of the breast N obtained in step S212 is smaller than the threshold (less than the threshold). Note that the control unit 52 may detect a pixel whose hardness value is equal to or less than a threshold, without limiting to the present embodiment.

  In the next step S224, the control unit 52 determines whether or not to display other types of images other than the elastography image. If the type of the image received in step S200 is only an elastography image, the determination is negative and the process proceeds to step S228. On the other hand, for example, when the display of the radiation image and the elastography image captured in the above-described continuous imaging mode is received, etc., an image other than the elastography image is included in the type of the received image. , Shift to step S226.

  In step S226, the control unit 52 acquires an image corresponding to the type of the accepted image from the storage unit 54. As described above, when the information for identifying the image is received, the image corresponding to the received information is acquired.

  At the next step S228, the control unit 52 causes the display unit 56 to display an image. When displaying an elastography image and a radiation image, in the present embodiment, the control unit 52 causes the display unit 56 to display the radiation image 70 and the elastography image 72, as illustrated in FIGS. 7 and 8. Display side by side. Note that FIG. 7 shows an example of the display of the radiation image 70 and the elastography image 72 when the warning is not displayed, and FIG. 8 shows the radiation image 70 and the elastography when the warning is displayed. An example of the display with the graphic image 72 is shown.

  In one example shown in FIGS. 7 and 8, the radiation image 70 includes a breast image 71, and the breast image 71 includes an object of interest image 74 of an object of interest such as a tumor. Further, in the elastography image 72, the hardness of the tissue of the breast area 73 is indicated by the density (density) of the dots instead of the color according to the hardness for convenience of illustration. Comparing the radiation image 70 and the elastography image 72, it can be seen that the position of the elastography image 72 corresponding to the object image 74 in the radiation image 70 shows that the breast tissue is hardened.

  Further, in the example shown in FIG. 8, the control unit 52 makes the numerical value of the hardness in the elastography image 72 be less than the threshold (in the specific example shown in FIG. Warning display 75 has been made. In the example shown in FIG. 8, the warning display 75 indicates the pixel area where the warning should be displayed with an arrow, and displays “It is a caution area”, thereby prompting the user's attention. The warning display 75 is not limited to this.

  The display state of the radiation image 70 and the elastography image 72 is not limited to the state in which the radiation image 70 and the elastography image 72 are displayed side by side as illustrated in FIGS. 7 and 8. For example, as shown in FIG. 9 as an example, the radiation image 70 and the elastography image 72 may be displayed in a superimposed manner (so-called superimposition). In addition, when the radiation image 70 and the elastography image 72 are superimposed and displayed, it is preferable that the corresponding portions of the breast image 71 and the breast area 73 be superimposed on each other. The radiation image 70 and the elastography image 72 may be displayed by detecting in the image and superimposing the detected skin line.

  In addition, a user's instruction is given to the state in which the radiation image 70 and the elastography image 72 are displayed side by side as illustrated in FIGS. 7 and 8 and the state in which the radiation image 70 and the elastography image 72 are displayed superimposed as illustrated in FIG. It may be switched by the like.

  For example, when displaying an ultrasound image such as a B-mode image and the elastography image 72 on the display unit 56, the control unit 52 replaces the radiation image 70 shown in FIGS. 7 and 8 with the ultrasound image. It may be displayed. When an ultrasound image and an elastography image are displayed, the display unit is a B-mode image of either the first ultrasound image or the second ultrasound image as an ultrasound image displayed together with the elastography image 72. It may be displayed on 56. In this case, the execution of the process of step S226 can be omitted.

  After the image including the elastography image 72 is displayed on the display unit 56 in this manner, the control unit 52 determines whether a plurality of images are displayed on the display unit 56 in step S230. When a plurality of images are not displayed on the display unit 56, a negative determination is made, and the present image display processing is ended. On the other hand, when a plurality of images are displayed on the display unit 56, an affirmative determination is made and the process proceeds to step S232.

  In step S232, the control unit 52 determines whether or not the user has received, via the input unit 57, a designation of an image representing a region of interest (ROI) of the displayed image. In the console 50 according to the present embodiment, when a plurality of images are displayed on the display unit 56, another image displayed corresponding to an image representing a region of interest designated by the user for one image You can display the position within.

  In addition, the designation method of the image showing the object of interest by the input unit 57 is not particularly limited. For example, using a pointing device such as a mouse as the input unit 57, an image of an object of interest (abnormal shadow of object of interest, etc.) from the image displayed on the display unit 56, a region of interest including the object of interest, or the position of interest of the object of interest The image representing the object of interest may be designated by designating (x, y coordinates) using the input unit 57 such as the pointing device. For example, when specifying the object of interest image 74 of the breast image 71 in the radiation image 70, the user uses the mouse pointer 81 as a pointing device on the display unit 56 as shown in an example in FIG. The region of interest 80 may be specified.

  If the designation of the image representing the region of interest is not accepted even after the predetermined time has elapsed, the determination is negative and the present image display process is ended. On the other hand, when the designation of the image representing the object of interest is accepted, the determination is positive and the process proceeds to step S234.

  In step S234, the control unit 52 detects the position of the image representing the designated region of interest. The control unit 52 first detects the position of the image representing the region of interest in the specified image. Furthermore, the control unit 52 detects a position in another image corresponding to the detected position. For example, in the example shown in FIG. 7, when the object of interest image 74 in the radiation image 70 is designated by the user via the input unit 57, the control unit 52 generates the object of interest 74 in the elastography image 72. Detect the corresponding position.

  In the next step S236, the control unit 52 causes the display unit 56 to display the detected position, and then ends the present image display process. The example shown in FIG. 11 shows the case where information 76 representing the position corresponding to the object image of interest 74 is displayed. In the example shown in FIG. 11, the position corresponding to the object image 74 is indicated by an arrow as the information 76, and “ROI” is displayed to indicate the position corresponding to the object image 74 to the user. However, the information 76 is not limited to this.

  Further, in the present embodiment, as shown in FIG. 11, the control unit 52 causes the display unit 56 to display the elastography image 72 in the B mode images 82A and 82B according to the detected position. In the example shown in FIG. 11, first, specifically, the control unit 52 obtains the center position (or the position of the center of gravity) of the object image 74 of interest by image analysis. Then, the control unit 52 sets the B-mode image 82A in the A-A line cross section (the cross section in the Y-axis direction shown in FIG. 2) passing the central position and the B-B line cross section (shown in FIG. The B-mode image 82B in the cross section in the X-axis direction is displayed in a state where it is easy to compare with the elastography image 72. In FIG. 11, for convenience of illustration, the B mode images 82A and 82B corresponding to the positions of the breast regions 73 and the like in the elastography image 72, and the B modes in order to clarify the positions of the breast regions 83A and 83B and the like in each As in the elastography image 72, dots of different densities (grayscales) are applied to the images 82A and 82B.

  When the user designates a position on breast N in a state where elastography image 72 and B-mode images 82A and 82B are displayed on display unit 56 as in the example shown in FIG. The display on the display unit 56 may be changed to the B mode images 82A and 82B in the cross section at the instructed position. As a specific example, FIG. 12 shows a case where the user moves the position of the display 85 representing the B-B line from the position of the ROI to a position approaching the nipple using the mouse pointer 81. In this case, instead of the B mode image 82B in the B-B line cross section shown in FIG. 11, as shown in FIG. Is displayed.

  In the present embodiment, as shown in FIG. 10 in step S232 (refer to FIG. 6) of the image display processing, the case where the ROI (the object image 74 of interest) is specified for the radiation image 70 will be described in detail. However, it is needless to say that the user may designate an ROI with respect to other images displayed on the display unit 56 without being limited to this. For example, in the example shown in FIG. 10, an ROI may be designated for the elastography image 72. In this case, as described above, it is preferable to display the B-mode images 82A and 82B according to the position of the ROI designated with respect to the elastography image 72 as shown in FIG.

In addition, the designation method of the image showing the object of interest by the input unit 57 is not particularly limited. For example, using a pointing device such as a mouse as the input unit 57, an image of an object of interest (abnormal shadow of object of interest, etc.) from the image displayed on the display unit 56, a region of interest including the object of interest, or the position of interest of the object of interest The image representing the object of interest may be designated by designating (x, y coordinates) using the input unit 57 such as the pointing device. For example, when specifying the object of interest image 74 of the breast image 71 in the radiation image 70, the user uses the mouse pointer 81 as a pointing device on the display unit 56 as shown in an example in FIG. The region of interest 80 may be specified.
Second Embodiment
Next, a second embodiment will be described. The same parts as those of the medical imaging system 1 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The configuration of the medical imaging system 1 is the same as that of the medical imaging system 1 (see FIGS. 1 and 2) according to the first embodiment, and thus the description thereof is omitted.

  In the present embodiment, the method of capturing the first ultrasonic image and the second ultrasonic image is different from that of the first embodiment. The medical imaging apparatus 10 according to the first embodiment causes the probe moving mechanism 38 to scan the ultrasonic probe 36 along the upper surface of the compression plate 32 at a constant speed (including a margin of error) at a first velocity. The image and the second ultrasound image were taken. On the other hand, in the medical imaging apparatus 10 of the present embodiment, at the position corresponding to the region of interest included in the breast N, the speed at which the ultrasound probe 36 is scanned is made slower than at other positions to perform the first A sound wave image and a second ultrasound image are taken.

  Therefore, as shown in FIG. 13, the entire flow of a series of imaging operations in the case of imaging in the continuous imaging mode in the medical imaging apparatus 10 of the present embodiment is in the continuous mode in the medical imaging apparatus 10 of the first embodiment. An exemplary flow of the photographing operation in the case of photographing (see FIG. 4) and step S106 and step S108 differ in that the processing of steps S107A to S107D is performed.

  In the present embodiment, the image data of the radiation image captured by the medical imaging apparatus 10 in step S106 is output to the console 50.

  Therefore, as shown in FIG. 13, in the next step S107A, the control unit 52 of the console 50 causes the display unit 56 to display the radiation image acquired from the medical imaging apparatus 10 as shown in FIG.

  In the next step S107B, whether or not the control unit 52 receives an instruction of an image representing a region of interest (ROI) performed by the user via the input unit 57 with respect to the radiation image 70 displayed on the display unit 56 Determine There is no particular limitation on the method of designating an image representing the object of interest by the input unit 57. For example, the method may be similar to step S232 of the image display process (see FIG. 6) described above in the first embodiment.

  If the designation of the image representing the region of interest is not accepted even after the predetermined time has elapsed, the determination is negative and the process proceeds to step S108. On the other hand, when the instruction of the image representing the region of interest is received, the determination is positive and the process proceeds to step S107C.

  In step 107C, the control unit 52 detects the position of an image representing the designated region of interest in the radiation image 70. For example, in the example shown in FIG. 14, when the user designates the object image 74 of interest via the input unit 57, the object image 74 of interest is detected from the radiation image 70.

  In the next step S107D, when capturing an ultrasound image, the control unit 52 determines and determines the position (position on the upper surface of the compression plate 32) at which the scanning speed for scanning the ultrasonic probe 36 is changed (or delayed). The specified position is instructed to the medical imaging apparatus 10.

  The position at which the scanning speed is to be changed is, for example, the correspondence between the position of the upper surface of the compression plate 32 and the pixels in the radiation image 70 in advance, and the region of interest detected in step S107C based on the correspondence. The position of the upper surface of the compression plate 32 corresponding to the position of the pixel of the image representing H may be determined.

  In the console 50 of the present embodiment, as described above, in the example shown in FIG. 14, when the user designates the object image 74 of interest via the input unit 57, the upper surface of the compression plate 32 shown as an example in FIG. The position corresponding to the inside of the rectangular area 84 is determined as the position for changing the scanning speed, and the position of the upper surface of the compression plate 32 is instructed to the medical imaging apparatus 10.

  In the imaging of the first ultrasonic image in step S116 performed after this step and the imaging of the second ultrasonic image in step S118, the medical imaging device 10 receives the upper surface of the compression plate 32 according to the instruction performed in step S107D. In the position corresponding to the inside of the rectangular area 84, the scanning speed at which the ultrasonic probe 36 scans is slower than the other positions. The degree of reducing the scanning speed is not particularly limited. By decreasing the scanning speed, although the detection accuracy of the hardness of the tissue of the breast N is increased, the time for pressing the breast is increased and the burden on the subject is increased. Just do it.

  As described above, in the medical imaging system 1 of the present embodiment, the radiation image 70 is determined by determining the position corresponding to the inside of the rectangular area 84 including the object image 74 of the upper surface of the compression plate 32 as the position to change the scanning speed. The scanning speed in the case of scanning the position corresponding to the object region of interest extracted from the ultrasonic probe 36 can be slower than the scanning speed of other positions. Thereby, according to the medical imaging system 1 of this embodiment, the detection accuracy of the hardness of the object of interest can be improved. In addition, since the control for reducing the scanning speed is not performed at the position outside the object region of interest, the time required to take an ultrasound image becomes longer, and the time to press the breast becomes longer, which causes the burden on the subject. It is possible to suppress the increase.

  As described above, the control unit 52 of the console 50 in the medical imaging system 1 of each of the above embodiments squeezes the breast N with each of a plurality of different pressures of the first compression pressure and the second compression pressure by the compression plate 32 A plurality of ultrasound images (first ultrasound image and second ultrasound image) ultrasonically captured in step (b) are acquired from the medical imaging apparatus 10. Further, the control unit 52 of the console 50 obtains the amount of change in the corresponding point between the first ultrasonic image and the second ultrasonic image using the acquired first and second ultrasonic images, and the corresponding point Information indicating the hardness of the tissue of the breast N is derived based on the amount of change (the amount of change in pixel value) of

  In the console 50 according to each of the above embodiments, the amount of change in pixel value at the corresponding portion in each of the acquired first and second ultrasound images, and the second compression pressure and the first compression pressure. Based on the difference, the hardness of the tissue of breast N is quantified.

  The conventional general elastography detects whether it is hard or soft as compared to the surrounding tissue, but with the console 50 of this embodiment, the hardness of the tissue of the breast N is obtained as a standardized value. Therefore, the hardness of the tissue of the breast N can be stably measured as an absolute value. According to the console 50 of the present embodiment, since the numerical value indicating the hardness of the tissue of the breast N can be stably measured regardless of the procedure of the operator or the like, the breast N can be appropriately measured even when the operator is unfamiliar Information indicative of the hardness of the tissue (e.g., the elastography image 72 described above) can be derived.

  In each of the above embodiments, when performing elastography, the breast N is compressed by two types of compression pressure, the first compression pressure and the second compression pressure, but the breast N is compressed by three or more types of compression pressure. The ultrasound image may be taken at each compression pressure. For example, the first ultrasonic image to the third ultrasonic image may be captured by compressing the breast N with three types of compression pressure of the first compression pressure to the third compression pressure. In this case, for example, the numerical value indicating the hardness of the tissue of the breast N derived from the first ultrasonic image and the second ultrasonic image, and the value of the tissue of the breast N derived from the second ultrasonic image and the third ultrasonic image An average value (including an average value obtained after weighting) with a numerical value indicating hardness may be derived as the hardness of the final breast N tissue.

  In each of the above embodiments, after the first ultrasound image of the entire breast N is captured in a state in which the breast N is compressed by the first compression pressure, the entire breast N is compressed in a state in which the breast N is compressed by the second compression pressure. Although the 2nd ultrasound image was image | photographed, the imaging method of the ultrasound image in each compression pressure is not limited to this. For example, in a state where the breast N is compressed by the first compression pressure, the ultrasonic wave is transmitted from the ultrasonic probe 36 and the ultrasonic echo reflected inside the breast N is received. Thereafter, the breast N is compressed by the second compression pressure without moving the ultrasonic probe 36, and again, ultrasonic waves are transmitted from the ultrasonic probe 36 and ultrasonic echoes reflected inside the breast N are received, The ultrasonic probe 36 is moved. At the moved position, transmission of ultrasonic waves by the ultrasonic probe 36 and reception of ultrasonic echoes in a state in which the breast N is compressed again by the first compression pressure, and ultrasound in a state in which the breast N is compressed by the second compression pressure Transmission of ultrasonic waves by the probe 36 and reception of ultrasonic echoes are performed. The first ultrasonic image and the second ultrasonic image of the entire breast N are captured by repeatedly performing a series of processes by the compression, the transmission of ultrasonic waves, the reception of ultrasonic echoes, and the movement of the ultrasonic probe 36. It is also good.

  In each of the above embodiments, the medical imaging apparatus 10 has the function of imaging a radiation image and the function of imaging an ultrasound image. However, the present invention is not limited thereto. It only needs to have a function of capturing an image. In the case of taking a radiation image of the breast in a general mammography device, the breast of the subject is pressed by a compression plate. On the other hand, when capturing an ultrasound image of the breast with a general ultrasound imaging apparatus, the operator moves the ultrasound probe on the surface of the subject's breast to perform imaging. As described above, since the compression state and the imaging state of the subject's breast are different between the case of capturing a radiation image and the case of capturing an ultrasound image, when comparing both images, observation of a region of interest, etc. May be difficult to On the other hand, as in the case of the medical imaging apparatus 10 of the present embodiment, the case of imaging a radiographic image and the case of imaging an ultrasonic image by having a function of imaging a radiographic image and a function of imaging an ultrasonic image It can suppress that the compression state of a subject's breast, the state of imaging | photography, etc. differ. Thus, according to the medical imaging apparatus 10 of the present embodiment, the user can easily compare the radiation image and the ultrasound image.

  Further, the medical imaging apparatus 10 may be an apparatus capable of performing so-called tomosynthesis imaging in which radiation images are taken at different irradiation angles with different irradiation angles of the radiation R to the breast N. In this case, a radiation image obtained by tomosynthesis imaging or a tomographic image obtained by reconstructing a plurality of radiation images obtained by tomosynthesis imaging may be used as a substitute for the radiation image in each of the above embodiments, for example And the elastography image may be displayed on the display unit 56.

  In each of the above embodiments, a warning is displayed when the tissue of the breast N is hard based on a predetermined threshold value. However, a plurality of threshold values are provided, and depending on the hardness of the tissue of the breast N Warnings may be displayed step by step. For example, you may use except a threshold as a standard which displays a warning. For example, a diagnostic method of performing color pattern diagnosis from a commonly used elastographic image may be applied. Color pattern diagnosis is classified into any of score 1 to score 5 from the color tone (balance of green and blue) corresponding to the tissue inside and around the tumor of the elastography image, and as the score increases, malignant It is a diagnostic method that raises certainty. When color pattern diagnosis is applied, a score for displaying a warning may be set in advance in the apparatus, or may be set by the user.

  In each of the above embodiments, the control unit 52 is based on the amount of change in the pixel value of the pixel as an example of the amount of change in the pixel at the corresponding portion of the breast N in each of the first ultrasound image and the second ultrasound image. Although the information indicating the hardness of the tissue of the breast N has been derived, it is not limited thereto. For example, the control unit 52 may use the amount of change in the position of the pixel of the corresponding part as an example of the amount of change in the pixel. The amount of positional deviation at which the position of a pixel specified in the first ultrasound image or a pixel serving as a feature point (any one may be one pixel or a region by a plurality of pixels) may be shifted in the second ultrasound image , The smaller the tissue of breast N, the smaller. Therefore, the stiffness of the breast can be derived by using the amount of displacement, that is, the amount of change in position. Although the method of detecting corresponding pixels in the first ultrasonic image and the second ultrasonic image is not particularly limited, for example, it may be detected by CAD (computer-aided diagnosis). Further, in this case, the "variation amount" in the above equation (1) for deriving the hardness may be set as the variation amount of the position of the corresponding pixel.

  In each of the above embodiments, the user designates or designates the region of interest, but the region of interest (image representing the region of interest) may be automatically detected from the image. For example, CAD may automatically detect the object of interest from the image.

  Although the position at which the scanning speed of the ultrasonic probe 36 is changed is determined according to the object image instructed in the radiation image, the present invention is not limited to the radiation image. For example, the first ultrasonic image may be displayed on the display unit 56 The position to change the scanning speed of the ultrasound probe 36 in the imaging of the second ultrasound image may be determined according to the object image displayed and displayed in the first ultrasound image. In this case, an image that displays the processing corresponding to step S107A to step S107D in the overall flow of a series of shooting operations when shooting in the continuous shooting mode shown in FIG. 13 between step S116 and step S117. Are changed to the first ultrasound image.

  In each of the above embodiments, the control unit 52 of the console 50 has the functions of the respective units of the hardness deriving device of the present invention. However, the present invention is not limited to this embodiment. The device of the present invention may have some or all of the functions of the respective parts of the hardness deriving device.

  In addition, the radiation R in each said embodiment is not specifically limited, An X ray, a gamma ray, etc. are applicable.

  In addition, the configuration, the operation, and the like of the medical imaging apparatus 10 and the like described in the above-described embodiments are merely examples, and it is needless to say that changes can be made according to the circumstances without departing from the scope of the present invention.

Reference Signs List 1 medical imaging system 10 medical imaging apparatus 20 arm unit 21 compression unit 22 base 24 shaft unit 25 radiation emission unit 26 radiation tube 28 filter 29 high voltage generation unit 30 radiation detector 31 imaging platform 32 compression plate 33 pressure sensor 34 compression plate Movement mechanism 36 ultrasonic probe 37 position sensor 38 probe movement mechanism 40, 52 control unit 40A, 52A CPU
40B, 52B ROM
40C, 52C RAM
42, 54 storage unit 44 operation panel 46, 58 I / F unit 49, 59 bus 50 console 56 display unit 57 input unit 60 acoustic matching member 62 echo jelly 70 radiation image 71 breast image 72 elastography image 73, 83A, 83B breast Region 74 Object of interest image 75 Warning display 76 Information 80 Region of interest 81 Mouse pointer 82A, 82B, 86B B-mode image 84 Display of rectangular area 85 B-B line N Breast R Radiation

Claims (14)

A radiation image acquisition unit for acquiring a radiation image of the breast compressed by the first compression pressure by the compression member;
While maintaining the compression of the breast with the first compression pressure by the compression member, the first ultrasound image of the breast that has been ultrasonically captured, and a second compression pressure different from the first compression pressure, An ultrasound image acquisition unit for acquiring a plurality of ultrasound images including a second ultrasound image of the breast ultrasonically imaged in a state in which the breast is compressed by a compression member;
The amount of change in corresponding points between the plurality of ultrasonic images is determined using the plurality of ultrasonic images acquired by the ultrasonic image acquisition unit, and the hardness of the tissue of the breast is determined based on the amount of change in the corresponding points. A derivation unit for deriving information indicating
Hardness derivation device equipped with. The derivation unit determines a pixel of a corresponding portion of the breast in each of the plurality of ultrasound images acquired by the ultrasound image acquisition unit as the corresponding point, and the variation of the pixel value of the pixel which is the corresponding point Deriving information indicating hardness of the breast tissue based on
The hardness deriving device according to claim 1. The deriving unit sets a pixel of a corresponding portion of the breast in each of the plurality of ultrasound images acquired by the ultrasound image acquiring unit as the corresponding point, and the variation of the position of the pixel which is the corresponding point. Deriving information indicative of hardness of the breast tissue based on
The hardness deriving device according to claim 1. The display control unit further includes a control unit configured to control the display unit to display an elastography image obtained using a color corresponding to the hardness indicated by the information derived by the derivation unit.
The hardness deriving device according to any one of claims 1 to 3. The display control unit performs control of causing the display unit to display the radiation image and the elastography image side by side or overlapping each other.
The hardness deriving device according to claim 4. It further comprises an object of interest receiving unit for receiving designation of a region of interest in any one of the radiation image and the elastography image displayed on the display unit,
The display control unit detects the position of the object of interest received by the object of interest receiving unit from the image in which the object of interest is specified among the radiation image and the elastography image, and the object of interest Control is performed to display information representing a position corresponding to the position of the detected object region in an image not designated.
The hardness deriving device according to claim 5. The ultrasound image acquisition unit scans the breast with ultrasound in a state in which the breast is compressed by each of the plurality of pressures including the first compression pressure and the second compression pressure by the compression member. Acquiring the plurality of ultrasound images from an ultrasound imaging apparatus that performs ultrasound imaging on the
The display control unit causes the display unit to display the radiation image;
It further comprises an object of interest image receiving unit for receiving an instruction of an image of an object of interest from the radiation image displayed on the display unit,
The position of the image of the object of interest received by the object of interest image receiving unit is detected from the radiation image, and at a position corresponding to the position of the image of the object of interest detected, the speed at which the ultrasonic wave is scanned The imaging control unit is provided to perform control to the ultrasonic imaging apparatus to make it slower than
The hardness deriving device according to any one of claims 4 to 6. The ultrasound image acquisition unit scans the breast with ultrasound in a state in which the breast is compressed by each of the plurality of pressures including the first compression pressure and the second compression pressure by the compression member. Acquiring the plurality of ultrasound images from an ultrasound imaging apparatus that performs ultrasound imaging on the
The ultrasound image detects a position of an image of an object of interest from the radiation image and, at a position corresponding to the detected position of the image of interest, controls ultrasound scanning speed to be slower than other positions. A photographing control unit for the photographing apparatus,
The hardness deriving device according to any one of claims 1 to 6. The ultrasound image acquisition unit scans the breast with ultrasound in a state in which the breast is compressed by each of the plurality of pressures including the first compression pressure and the second compression pressure by the compression member. Acquiring the plurality of ultrasound images from an ultrasound imaging apparatus that performs ultrasound imaging on the
The position of the object of interest corresponding to the object of interest contained in the breast is provided with an imaging control unit for performing control to make the ultrasonic scanning speed slower than other positions with respect to the ultrasonic imaging apparatus ,
The hardness deriving device according to any one of claims 1 to 6. When the hardness represented by the information derived by the derivation unit is harder than the threshold hardness, a warning unit displays and warns information indicating the position of the breast tissue harder than the threshold hardness Further equipped with
The hardness deriving device according to any one of claims 1 to 9. It further comprises a hardness reception unit that receives the setting of the hardness to be the threshold value,
The warning unit displays and warns information indicating the position of the breast tissue that is harder than the threshold hardness received by the hardness reception unit.
The hardness deriving device according to claim 10. Ultrasound imaging of the breast is performed by scanning the breast with ultrasound while the breast is compressed by each of a plurality of pressures including the first compression pressure and the second compression pressure by the compression member. An ultrasound imaging apparatus for outputting a plurality of ultrasound images;
The hardness deriving device according to any one of claims 1 to 11, wherein the plurality of ultrasound images output from the ultrasound imaging apparatus are acquired by an acquisition unit.
Medical imaging system equipped with Acquiring a radiation image of the breast compressed by the first compression pressure by the compression member;
While maintaining the compression of the breast with the first compression pressure by the compression member, the first ultrasound image of the breast that has been ultrasonically captured, and a second compression pressure different from the first compression pressure, Acquiring a plurality of ultrasound images including a second ultrasound image of the breast ultrasonically captured in a state in which the breast is compressed by a compression member;
The amount of change in corresponding points between the plurality of ultrasonic images is determined using a plurality of acquired ultrasonic images, and information indicating the hardness of the tissue of the breast is derived based on the amount of change in the corresponding points. ,
Hardness derivation method for making a computer execute processing including the above. Acquiring a radiation image of the breast compressed by the first compression pressure by the compression member;
While maintaining the compression of the breast with the first compression pressure by the compression member, the first ultrasound image of the breast that has been ultrasonically captured, and a second compression pressure different from the first compression pressure, Acquiring a plurality of ultrasound images including a second ultrasound image of the breast ultrasonically captured in a state in which the breast is compressed by a compression member;
The amount of change in corresponding points between the plurality of ultrasonic images is determined using a plurality of acquired ultrasonic images, and information indicating the hardness of the tissue of the breast is derived based on the amount of change in the corresponding points. ,
Hardness deriving program for making a computer execute processing including the above.