Ultrasonic diagnostic apparatus

Abstract

To reflect a scan position of ultrasonic waves on a model that is independent of a subject by a simplified technique.SOLUTION: A position sensor 14 acquires position information of an ultrasonic probe 12. A recognition unit 36 recognizes a scan cross-section scanned by ultrasonic waves on the basis of an ultrasonic image acquired by scanning of the ultrasonic waves by the ultrasonic probe 12. A conversion unit 38 uses an anatomical model in which a correct cross-section on which an ultrasonic examination should be performed and a correct position of the correct cross-section are registered, and converts the position indicated by the position information into the correct position associated with the anatomical model in accordance with conversion rules. A display control unit 28 displays, on a display unit 22, extraction information related to the ultrasonic examination corresponding to the correct position. An update unit 40 updates the conversion rules by using the correct position of the correct cross-section corresponding to the scan cross-section recognized by the recognition unit 36 and the position indicated by the position information.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an ultrasonic diagnostic apparatus.

Background Art

[0002] In ultrasonic examinations, a user such as an examiner may identify the scanning position by ultrasound while viewing an ultrasonic image.

[0003] Patent Document 1 describes a technique for identifying a cross-section scanned by ultrasound by combining the position detected by a position sensor provided in an ultrasonic probe with image analysis.

[0004] Patent Document 2 describes a technique for identifying a cross-section scanned by ultrasound by using a CT (Computed Tomography) image and an ultrasonic image.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Generally, in order for a user to accurately identify the scanning position, experience and knowledge are required. Therefore, it is not easy for the user to identify the scanning position. In addition, since the identification of the scanning position depends on the user's experience and knowledge, the objectivity of the identified scanning position is poor.

[0007] An object of the present disclosure is to reflect the scanning position by ultrasound in a model independent of a subject by a simple method.

Means for Solving the Problems

[0008] One aspect of the present disclosure includes an acquisition unit that acquires position information of an ultrasonic probe, a recognition unit that recognizes a scanned cross-section where ultrasonic waves are scanned based on an ultrasonic image acquired by scanning with the ultrasonic probe, a conversion unit that uses an anatomical model in which a correct cross-section to be subjected to ultrasonic examination and a correct position of the correct cross-section are registered, and converts the position indicated by the position information acquired by the acquisition unit to the correct position associated with the anatomical model according to a conversion rule, a display control unit that causes a display to display extraction information related to ultrasonic examination corresponding to the correct position converted by the conversion unit, and an update unit that updates the conversion rule by using the correct position of the correct cross-section corresponding to the scanned cross-section recognized by the recognition unit and the position indicated by the position information acquired by the acquisition unit.

[0009] The conversion according to the conversion rule is a conversion using a conversion matrix, and the update unit may update the conversion matrix by using the position indicated by the position information acquired by the acquisition unit and the correct position of the correct cross-section.

[0010] For each examination site, a correct cross-section and a correct position may be registered in the anatomical model.

[0011] The ultrasonic diagnostic apparatus may further include a setting unit that sets an anatomical model corresponding to at least one of the body shape and body position of a subject to be subjected to ultrasonic examination as the anatomical model used for conversion.

[0012] At least one of the body shape and body position of the subject is specified by a user, and the setting unit may set an anatomical model corresponding to the at least one specified by the user as the anatomical model used for conversion.

[0013] The setting unit may estimate at least one of the body shape and body position of the subject based on an image generated by photographing the subject with a camera, and set an anatomical model corresponding to the estimation result as the anatomical model used for conversion.

[0014] The setting unit may receive subject identification information for identifying the subject, and set an anatomical model corresponding to the body shape indicated by the body shape information associated with the subject identification information as the anatomical model used for conversion.

[0015] The ultrasonic diagnostic apparatus further includes an estimation unit that estimates at least one of the body shape and body position of the subject based on the position of the ultrasonic probe, and the setting unit may set an anatomical model corresponding to the estimation result by the estimation unit as the anatomical model used for conversion.

[0016] The ultrasonic diagnostic apparatus further includes an estimation unit that estimates at least one of the body shape and body position of the subject based on the ultrasonic image, and the setting unit may set an anatomical model corresponding to the estimation result by the estimation unit as the anatomical model used for conversion.

[0017] When a change occurs in the body position of the subject, the update unit may newly create a conversion rule corresponding to the changed body position.

[0018] The extracted information may include at least one of information indicating the position of the ultrasonic probe, information indicating the orientation of the ultrasonic probe, information indicating the current scanning range by ultrasonic waves, information indicating the past scanning range by ultrasonic waves, and information indicating the unscanned range.

Advantages of the Invention

[0019] According to the present disclosure, the scanning position by ultrasonic waves can be reflected in a model independent of the subject by a simple method.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0021] With reference to FIG. 1, the ultrasonic diagnostic apparatus 10 according to the embodiment will be described. FIG. 1 is a block diagram showing an example of the configuration of the ultrasonic diagnostic apparatus 10 according to the embodiment.

[0022] The ultrasonic diagnostic apparatus 10 generates ultrasonic image data by transmitting and receiving ultrasonic waves using the ultrasonic probe 12. For example, the ultrasonic diagnostic apparatus 10 transmits ultrasonic waves into a subject and receives the ultrasonic waves reflected inside the subject, thereby generating ultrasonic image data representing the internal tissues of the subject.

[0023] The ultrasonic probe 12 is a device that transmits and receives ultrasonic waves. The ultrasonic probe 12 includes, for example, a 1D array transducer. The 1D array transducer is composed of a plurality of ultrasonic transducers arranged linearly. An ultrasonic beam is formed by the 1D array transducer, and the ultrasonic beam is repeatedly electronically scanned. As a result, a scanning cross-section is formed in the living body for each electronic scan. The scanning cross-section corresponds to a two-dimensional echo data acquisition space. The ultrasonic probe 12 may include a 2D array transducer formed by arranging a plurality of ultrasonic transducers two-dimensionally. When an ultrasonic beam is formed by the 2D array transducer and the ultrasonic beam is repeatedly electronically scanned, a scanning cross-section as a two-dimensional echo data acquisition space is formed for each electronic scan. When the ultrasonic beam is scanned two-dimensionally, a three-dimensional space as a three-dimensional echo data acquisition space is formed. As the scanning method, sector scanning, linear scanning, convex scanning, or the like is used.

[0024] The position sensor 14 is provided on the ultrasonic probe 12 and detects the position of the ultrasonic probe 12. The position information indicating the position of the ultrasonic probe 12 is output to the analysis unit 34. Hereinafter, the position of the ultrasonic probe 12 detected by the position sensor 14 is referred to as the "actual position". The actual position is the position where the ultrasonic probe 12 is actually provided. For example, the position sensor 14 detects the relative position of the ultrasonic probe 12 with respect to the subject, the rotation direction, the rotation speed, and the inclination (for example, the posture). The position information includes information indicating the relative position, information indicating the rotation direction, information indicating the rotation speed, and information indicating the inclination. The position sensor 14 corresponds to an example of an acquisition unit.

[0025] A known sensor is used as the position sensor 14. For example, the position sensor 14 is a sensor that detects three-axis acceleration and three-axis angular velocity (for example, an acceleration sensor and a gyro sensor). The position sensor 14 may be a magnetic sensor. When a magnetic sensor is used as the position sensor 14, the magnetic sensor measures the intensity of the magnetic field emitted from a magnetic generator installed at a predetermined position to detect the actual position of the ultrasonic probe 12.

[0026] The transmission / reception unit 16 functions as a transmission beamformer and a reception beamformer. During transmission, the transmission / reception unit 16 supplies a plurality of transmission signals having a certain delay relationship to a plurality of ultrasonic transducers included in the ultrasonic probe 12. Thereby, an ultrasonic transmission beam is formed. During reception, a reflected wave (RF signal) from the living body is received by the ultrasonic probe 12, and thereby, a plurality of reception signals are output from the ultrasonic probe 12 to the transmission / reception unit 16. The transmission / reception unit 16 forms a reception beam by applying an in-phase addition process to the plurality of reception signals. The data of the reception beam is output to the image generation unit 18. That is, the transmission / reception unit 16 performs a delay process on the reception signals obtained from each ultrasonic transducer according to the delay process conditions for each ultrasonic transducer, and forms a reception beam by adding the plurality of reception signals obtained from the plurality of ultrasonic transducers. The delay process conditions are defined by reception delay data indicating a delay time. A set of reception delay data (that is, a set of delay times) corresponding to the plurality of ultrasonic transducers is supplied from the control unit 26.

[0027] Due to the operation of the transmission / reception unit 16, an ultrasonic beam (that is, a transmission beam and a reception beam) is electronically scanned, and thereby, a scanning cross section is formed. The scanning cross section corresponds to a plurality of beams, and the plurality of beams constitute a reception frame (specifically, an RF signal frame). Each beam is composed of a plurality of echoes arranged in the depth direction. By repeating the electronic scanning of the ultrasonic beam, a plurality of reception frames arranged on the time axis are output from the transmission / reception unit 16 to the image generation unit 18. The plurality of reception frames constitute a reception frame sequence.

[0028] When the ultrasonic beam is two-dimensionally electronically scanned by the operation of the transmission / reception unit 16, a three-dimensional echo data acquisition space is formed, and volume data as an echo data aggregate is acquired from the three-dimensional echo data acquisition space. By repeating the electronic scanning of the ultrasonic beam, a plurality of volume data arranged on the time axis are output from the transmission / reception unit 16 to the image generation unit 18. The plurality of volume data constitute a volume data sequence.

[0029] The image generation unit 18 generates ultrasonic image data (e.g., B-mode image data) by applying signal processing such as detection, amplitude compression (e.g., logarithmic compression), and conversion functions (coordinate conversion function and interpolation processing function by DSC (Digital Scan Converter), etc.) to the received frame output from the transmission / reception unit 16. Hereinafter, the image data is appropriately referred to as "image". For example, the ultrasonic image data is appropriately referred to as "ultrasonic image", or the B-mode image data is appropriately referred to as "B-mode image". Note that the ultrasonic image according to the present embodiment is not limited to the B-mode image, and may be any image generated by the ultrasonic diagnostic apparatus 10. For example, the ultrasonic image according to the present embodiment may be a color Doppler image, a pulsed Doppler image, a strain imaging image, or a shear wave elastography image.

[0030] The display processing unit 20 generates a display image by performing overlay processing on the graphic data necessary for the ultrasonic image. The display image is output to the display unit 22. One or more images are displayed side by side in a display mode.

[0031] The display unit 22 is a display such as a liquid crystal display or an EL display. An ultrasonic image such as a B-mode image is displayed on the display unit 22. The display unit 22 may be a device that also serves as a display and an operation unit 32. For example, a GUI (Graphic User Interface) may be realized by the display unit 22. Also, a user interface such as a touch panel may be realized by the display unit 22.

[0032] The storage unit 24 constitutes one or more storage areas for storing data. The storage unit 24 is, for example, a hard disk drive (HDD), a solid state drive (SSD), various memories (e.g., RAM, DRAM, ROM, etc.), other storage devices (e.g., optical disks, etc.), or a combination thereof.

[0033] The ultrasonic image generated by the imaging with the ultrasonic diagnostic apparatus 10, the information indicating the imaging conditions, and the information regarding the subject (e.g., patient), etc. are stored in the storage unit 24.

[0034] Also, the data of the anatomical model is stored in the storage unit 24 in advance. The anatomical model is a three-dimensional model simulating a standard human body (e.g., the upper body of a person). The anatomical model is a standard model independent of individual subjects.

[0035] The correct cross-section information indicating the cross-section (hereinafter referred to as the "correct cross-section") where the ultrasonic examination should be performed and the correct position information indicating the position of the correct cross-section (hereinafter referred to as the "correct position") are registered in the anatomical model in advance. The correct cross-section is the cross-section where ultrasonic waves should be scanned in the ultrasonic examination. The correct cross-section information is information indicating the range of the correct cross-section (i.e., a two-dimensional range) and the orientation of the correct cross-section. The correct position is a position on the three-dimensional model simulating the human body (e.g., a position on the body surface of the human body). For example, a plurality of different correct cross-sections and the correct positions of each correct cross-section are registered in the anatomical model.

[0036] In the ultrasonic examination, a plurality of different correct cross-sections where the ultrasonic examination should be performed are determined in advance, and a user such as a technician changes the position and orientation of the ultrasonic probe 12 on the subject so that each correct cross-section is scanned by ultrasonic waves, and executes the ultrasonic examination.

[0037] The control unit 26 controls the operations of each part of the ultrasonic diagnostic apparatus 10. The control unit 26 includes a display control unit 28 and a storage control unit 30.

[0038] The display control unit 28 causes the display unit 22 to display the ultrasonic image and other information.

[0039] For example, the display control unit 28 causes the display unit 22 to display the extraction information corresponding to the correct position. The extraction information is information related to the ultrasonic inspection. For example, the extraction information includes at least one of information indicating the actual position of the current ultrasonic probe 12, information indicating the orientation of the current ultrasonic probe 12, information indicating the current scanning range by ultrasonic waves (for example, information indicating the current scanning cross-section), information indicating the past scanning range by ultrasonic waves (for example, information indicating the past scanning cross-section), information indicating the unscanned range (for example, information indicating the scanning cross-section that has not yet been scanned by ultrasonic waves), and information indicating the orientation of the viewpoint. The information included in the extraction information may be specified by the user or may be predetermined. The information indicating the unscanned range is information indicating the correct cross-section.

[0040] For example, the information indicating the current scanning cross-section is the correct cross-section information indicating the correct cross-section corresponding to the current scanning cross-section (that is, the correct cross-section estimated to coincide with the scanning cross-section). The information indicating the past scanning cross-section is the correct cross-section information indicating the correct cross-section corresponding to the past scanning cross-section. The information indicating the unscanned scanning cross-section is the correct cross-section information indicating the correct cross-section corresponding to the unscanned scanning cross-section. These correct cross-section information are registered in advance in the anatomical model and stored in the storage unit 24 in advance.

[0041] The storage control unit 30 stores various information in the storage unit 24 and reads out various information from the storage unit 24.

[0042] The operation unit 32 is a device for the user to input conditions, commands, etc. necessary for imaging to the ultrasonic diagnostic apparatus 10. For example, the operation unit 32 is an operation panel, a switch, a button, a keyboard, a mouse, a trackball, or a joystick, etc.

[0043] The analysis unit 34 analyzes the ultrasonic image and specifies the correct position on the anatomical model corresponding to the actual position based on the analysis result and the actual position of the ultrasonic probe 12 (that is, the position detected by the position sensor 14). The display control unit 28 causes the display unit 22 to display the extraction information corresponding to the specified correct position.

[0044] The analysis unit 34 identifies the correct position corresponding to the actual position according to the conversion rule. For example, the conversion according to the conversion rule is the conversion using a conversion matrix. A conversion matrix is used for the method of identifying the correct position corresponding to the actual position. The analysis unit 34 obtains a conversion matrix for converting the actual position to the correct position, and uses the conversion matrix to identify the correct position corresponding to the actual position. Further, the analysis unit 34 updates the conversion matrix using the actual position and the correct position. By doing so, the accuracy of the position conversion becomes higher as the ultrasonic inspection progresses.

[0045] For example, the analysis unit 34 includes a recognition unit 36, a conversion unit 38, an update unit 40, a setting unit 42, and an estimation unit 44.

[0046] The recognition unit 36 recognizes the scanning cross-section scanned by the ultrasonic waves based on the ultrasonic image. For example, the recognition unit 36 estimates the scanning cross-section by performing cross-section recognition processing on the ultrasonic image. Estimating the scanning cross-section is to identify the correct cross-section from the anatomical model. That is, the recognition unit 36 identifies the correct cross-section estimated to match the scanning cross-section actually scanned by the ultrasonic waves from the anatomical model. Further, the recognition unit 36 calculates a confidence level representing the certainty of the estimation. The confidence level is sometimes referred to as the likelihood. The confidence level is an index indicating the degree of coincidence between the estimated scanning cross-section and the correct cross-section. The recognition unit 36 may estimate a plurality of scanning cross-sections and calculate the confidence level of each scanning cross-section.

[0047] The recognition unit 36 may estimate the currently scanned cross-section by performing cross-section recognition processing on the currently acquired ultrasonic image. That is, the recognition unit 36 may estimate the cross-section in real time.

[0048] As another example, the recognition unit 36 may estimate the scanning cross-section by performing cross-section recognition processing on the ultrasonic image that has already been acquired and stored in the storage unit 24 or an external device.

[0049] As the cross-section recognition process according to this embodiment, a known cross-section recognition process is used. For example, machine learning or artificial intelligence (AI) may be used for the cross-section recognition process. There is no limitation on the type of machine learning or artificial intelligence used, and any algorithm or model may be used. For example, CNN (Convolutional Neural Network), RNN (Recurrent Neural Network), GAN (Generative Adversarial Networks), linear models, random forest - decision tree learning, support vector machine (SVM), ensemble classifier, or other algorithms may be used. Pattern matching such as template matching, or algorithms that do not require learning such as correlation coefficient or similarity calculation may be used for the cross-section recognition process.

[0050] For example, the recognition unit 36 estimates the scanned cross-section by performing a cross-section recognition process using machine learning on the ultrasonic image, and calculates a confidence level representing the certainty of the estimation using the machine learning.

[0051] The recognition unit 36 may estimate the scanned cross-section by comparing an ultrasonic image (for example, a B-mode image) generated by transmitting and receiving ultrasonic waves with images of a plurality of correct cross-sections (for example, B-mode images). In this case, techniques such as pattern matching may be used.

[0052] The conversion unit 38 uses the anatomical model and converts the actual position of the ultrasonic probe 12 (hereinafter referred to as "actual position Pr") detected by the position sensor 14 to the correct position (hereinafter referred to as "correct position Pm") registered in the anatomical model according to the conversion rule. That is, the conversion unit 38 converts the actual position Pr of the ultrasonic probe 12 to the correct position Pm on the anatomical model. The correct position Pm is a position in a three-dimensional coordinate system.

[0053] Converting the actual position Pr to the correct position Pm corresponds to identifying which correct position Pm on the anatomical model the actual position Pr of the ultrasonic probe 12 corresponds to. That is, the correct position Pm obtained by converting the actual position Pr corresponds to the position of the ultrasonic probe 12 on the anatomical model.

[0054] The conversion according to the conversion rule is a conversion using the conversion matrix M. The actual position Pr and the correct position Pm of the ultrasonic probe 12 are converted into each other using the conversion matrix M. For example, the relationship between the actual position Pr and the correct position Pm is expressed by the following formula (1) by using the conversion matrix M. Pm = M·Pr ···(1)

[0055] When the actual position Pr and the correct position Pm are expressed as matrices, the conversion matrix M is expressed by the following formula (2). M = Pm·Pr -1 ···(2)

[0056] The conversion unit 38 converts the actual position Pr detected by the position sensor 14 into the correct position Pm on the anatomical model according to the above formula (1).

[0057] An initial conversion matrix M is predetermined and stored in the storage unit 24 in advance. As will be described later, the conversion matrix M is updated as needed as the inspection progresses. When the conversion matrix M is updated, the conversion unit 38 converts the actual position Pr into the correct position Pm using the updated conversion matrix M. By updating the conversion matrix M, the accuracy of the conversion is improved.

[0058] The update unit 40 updates the conversion rule (for example, the conversion matrix M) by using the correct position Pm of the correct cross-section corresponding to the scanned cross-section recognized by the recognition unit 36 and the actual position Pr of the ultrasonic probe 12. Specifically, the update unit 40 updates the conversion matrix M according to the above formula (2). Hereinafter, the update of the conversion matrix M will be described in detail.

[0059] As described above, the actual real position Pr of the ultrasonic probe 12 is detected by the position sensor 14. The recognition unit 36 estimates the scanning cross-section scanned by the ultrasonic waves. That is, the correct cross-section estimated to match the scanning cross-section actually scanned by the ultrasonic waves is specified from the anatomical model. The correct cross-section and the correct position Pm are registered in the anatomical model, and the update unit 40 specifies the correct position Pm of the estimated correct cross-section from the anatomical model. The update unit 40 calculates the transformation matrix M by inputting the real position Pr and the correct position Pm into Equation (2).

[0060] For example, as the ultrasonic examination progresses and the ultrasonic waves are scanned at a plurality of different real positions Pr, the plurality of different real positions Pr are detected by the position sensor 14. Also, for each real position Pr, the correct cross-section corresponding to the actual scanning cross-section is specified, and the correct position of the correct cross-section is specified. For example, every time the real position Pr and the correct position Pm are obtained, the update unit 40 calculates the transformation matrix M according to Equation (2). By doing so, the update unit 40 updates the transformation matrix M.

[0061] The setting unit 42 sets the anatomical model and the conversion rule (for example, the conversion matrix M) for at least one of the body shape and the body position of the subject.

[0062] The estimation unit 44 estimates at least one of the body shape and the body position of the subject based on the position and orientation of the ultrasonic probe 12. The setting unit 42 sets the anatomical model corresponding to the estimation result by the estimation unit 44 as the anatomical model used for conversion.

[0063] Details of the setting unit 42 and the estimation unit 44 will be described later. Note that the setting unit 42 and the estimation unit 44 may not be provided in the ultrasonic diagnostic apparatus 10.

[0064] Hereinafter, this embodiment will be described in more detail.

[0065] With reference to FIGS. 2 and 3, the update by the update unit 40 will be described. FIG. 2 shows the anatomical model 46. FIG. 3 shows the subject S.

[0066] The anatomical model 46 is a three-dimensional model simulating a standard human body. The subject S is a person (e.g., a patient, etc.) who is the subject of an ultrasonic examination.

[0067] The correct positions A, B, C, and D are shown in FIG. 2. The correct positions A, B, C, and D are positions on the anatomical model 46 and are an example of the correct position Pm. The correct positions A, B, C, and D are respectively the positions of the correct cross-sections.

[0068] The actual positions α, β, γ, and δ are shown in FIG. 3. The actual positions α, β, γ, and δ are positions on the body surface of the subject S and are positions in the real space. The actual positions α, β, γ, and δ are an example of the actual position Pr and are the positions detected by the position sensor 14.

[0069] In the example shown in FIGS. 2 and 3, the ultrasonic probe 12 is sequentially arranged at each of the actual positions α, β, γ, and δ, and ultrasonic waves are sequentially scanned at each actual position to generate an ultrasonic image. For example, in the order of the actual positions α, β, γ, and δ, the ultrasonic probe 12 is arranged at each actual position, and ultrasonic waves are scanned at each actual position. Thereby, ultrasonic images are acquired at each of the actual positions α, β, γ, and δ.

[0070] Assuming that the transformation matrix M expressed by Equation (2) is a 4×4 matrix, the update unit 40 generates the transformation matrix M based on the position information of the four positions of the actual positions α, β, γ, and δ and the position information of the four positions of the correct positions A, B, C, and D. As described above, the transformation matrix M is expressed by the matrix Pm and the matrix Pr. The matrix Pm is expressed by the coordinate values of the four correct positions. The matrix Pr is expressed by the coordinate values of the four actual positions.

[0071] Specifically, the ultrasonic probe 12 is arranged at the actual position α, and the actual position α is detected by the position sensor 14. The update unit 40 inputs the coordinate value of the actual position α into the column of the matrix Pr.

[0072] When the ultrasonic probe 12 is disposed at the actual position α, the scanning cross-section scanned by ultrasonic waves is estimated by the recognition unit 36. That is, the correct cross-section estimated to match the actually scanned cross-section by ultrasonic waves is specified from the anatomical model 46. The correct cross-section and the correct position Pm are registered in the anatomical model 46, and the update unit 40 specifies the correct position Pm of the estimated correct cross-section from the anatomical model 46. For example, the update unit 40 specifies the correct position A as the correct position Pm of the estimated correct cross-section. That is, the correct position of the correct cross-section estimated to match the cross-section at the actual position α is the correct position A. It can be said that the correct position A is the position on the anatomical model 46 corresponding to the actual position α. The update unit 40 inputs the coordinate value of the correct position A to the column of the matrix Pm corresponding to the column in which the coordinate value of the actual position α is input.

[0073] Regarding the coordinate values of the actual positions β, γ, and δ, similar to the coordinate value of the actual position α, they are input to the matrix Pr. Regarding the coordinate values of the correct positions B, C, and D, similar to the coordinate value of the correct position A, they are input to the matrix Pm.

[0074] That is, the ultrasonic probe 12 is disposed at the actual position β, and the actual position β is detected by the position sensor 14. The update unit 40 inputs the coordinate value of the actual position β to the column of the matrix Pr.

[0075] When the ultrasonic probe 12 is disposed at the actual position β, the scanning cross-section scanned by ultrasonic waves is estimated by the recognition unit 36. The update unit 40 specifies the correct position B as the correct position Pm of the estimated correct cross-section. That is, the correct position of the correct cross-section estimated to match the cross-section at the actual position β is the correct position B. It can be said that the correct position B is the position on the anatomical model 46 corresponding to the actual position β. The update unit 40 inputs the coordinate value of the correct position B to the column of the matrix Pm corresponding to the column in which the coordinate value of the actual position β is input.

[0076] The correct position of the correct cross-section estimated to coincide with the scanning cross-section of the actual position γ is the correct position C. The update unit 40 inputs the coordinate values of the actual position γ into the columns of the matrix Pr. The update unit 40 inputs the coordinate values of the correct position C into the columns of the matrix Pm.

[0077] The correct position of the correct cross-section estimated to coincide with the scanning cross-section of the actual position δ is the correct position D. The update unit 40 inputs the coordinate values of the actual position δ into the columns of the matrix Pr. The update unit 40 inputs the coordinate values of the correct position D into the columns of the matrix Pm.

[0078] The update unit 40 generates a transformation matrix M based on the matrix Pr composed of the coordinate values of the actual positions α, β, γ, δ respectively, and the matrix Pm composed of the coordinate values of the correct positions A, B, C, D respectively, according to formula (2). Thereby, a 4×4 transformation matrix M is generated.

[0079] After that, when ultrasonic waves are scanned at a new actual position and an ultrasonic image is generated, the update unit 40 inputs the coordinate values of the new actual position into the matrix Pr, and inputs the coordinate values of the correct position corresponding to the new actual position into the matrix Pm, thereby updating the transformation matrix M.

[0080] For example, the update unit 40 replaces the coordinate values input into the column with the oldest input order in the matrix Pr with the coordinate values of the new actual position. Similarly, the update unit 40 replaces the coordinate values input into the column with the oldest input order in the matrix Pm with the coordinate values of the correct position corresponding to the new actual position. For example, when the ultrasonic probe 12 is placed at the actual position ε and an ultrasonic image is generated after the ultrasonic waves are scanned at the actual position δ, the update unit 40 inputs the coordinate values of the actual position ε into the column in the matrix Pr where the coordinate values of the actual position α were input, instead of the coordinate values of the actual position α. Similarly, the update unit 40 inputs the coordinate values of the correct position corresponding to the actual position ε into the column in the matrix Pm where the coordinate values of the correct position A were input, instead of the coordinate values of the correct position A. By doing so, the update unit 40 updates the transformation matrix M.

[0081] Of course, this is just an example of the update. The update unit 40 may generate the transformation matrix M by inputting the coordinate values of the actual position where a highly reliable scanned cross-section is obtained into the matrix Pr and inputting the correct position corresponding to the actual position into the matrix Pm. By doing so, the transformation matrix M that enables more accurate position transformation can be generated. For example, when the transformation matrix M is a 4×4 matrix, the update unit 40 updates the transformation matrix M by using the top four coordinate values (the coordinate values of the actual position and the coordinate values of the correct position) with the highest confidence levels from the first to the fourth. As another example, the update unit 40 may determine the average value of a plurality of transformation matrices M used in the past as the transformation matrix M used for transformation. The update unit 40 may calculate the weighted transformation matrix M by using the average value of the confidence levels of each position as a weighting coefficient.

[0082] For example, immediately after the start of the ultrasonic inspection, the transformation matrix M is generated by using the ultrasonic images of the first four frames. For example, when the frame rate is 20, the transformation matrix M is generated in 0.2 seconds. As the inspection progresses, the transformation matrix M is updated, and the transformation matrix M that enables more accurate position transformation is generated.

[0083] In addition, in the example shown in FIG. 3, although the actual positions are separated from each other, the actual positions may be positions close to each other. For example, while slightly changing the position of the ultrasonic probe 12 near the actual position α, ultrasonic images may be acquired at a plurality of positions, and the transformation matrix M may be generated.

[0084] As yet another example, at the initial stage of the inspection, the transformation matrix M may be generated by performing ultrasonic scanning in a wider area.

[0085] In the above-described embodiment, the scanning cross-section is estimated and the transformation matrix M is generated. As another example, the recognition unit 36 may estimate the site scanned by the ultrasonic wave, and the conversion unit 38 may generate the transformation matrix M by using the position of the site. For example, the site may be a kidney, a gallbladder, an abdominal aorta, a hepatic vein bifurcation, or the like. For example, for each site, the site and its correct position are registered in advance in the anatomical model. The conversion unit 38 specifies the correct position corresponding to the site estimated by the recognition unit 36 from the anatomical model, and generates the transformation matrix M based on the actual position detected by the position sensor 14 and the correct position.

[0086] When the transformation matrix M is generated as described above, the conversion unit 38 uses the transformation matrix M to convert the actual position Pr detected by the position sensor 14 into the correct position Pm on the anatomical model according to the above-described formula (1). The display control unit 28 causes the display unit 22 to display the extraction information corresponding to the correct position Pm.

[0087] When the transformation matrix M is updated by the update unit 40, the conversion unit 38 uses the updated transformation matrix M to convert the actual position Pr into the correct position Pm. The display control unit 28 causes the display unit 22 to display the extraction information corresponding to the correct position Pm.

[0088] For example, when the actual position ζ of the ultrasonic probe 12 is detected by the position sensor 14, the conversion unit 38 uses the transformation matrix M to convert the actual position ζ into the correct position on the anatomical model. The display control unit 28 causes the display unit 22 to display the extraction information corresponding to the correct position. Further, the update unit 40 updates the transformation matrix M by using the coordinate value of the actual position ζ and the coordinate value of the correct position corresponding to the actual position ζ.

[0089] (Example) Hereinafter, examples will be described. Here, as an example, an ultrasonic examination targeting abdominal palpation will be described. For example, 25 correct cross-sections of the abdomen are registered in advance in the anatomical model. Specifically, the central coordinates (i.e., the correct positions) of each correct cross-section, the coordinate range of the correct cross-section, the name of the correct cross-section, and the orientation of the viewpoint with respect to the correct cross-section are registered in advance in the anatomical model. The data of the anatomical model is stored in advance in the storage unit 24.

[0090] For example, the initial value of the transformation matrix M is the identity matrix. At this stage, since the transformation using the transformation matrix M is not performed accurately, the extracted information is not displayed.

[0091] In the examination, usually, an overview scan is first performed. For example, by performing ultrasonic scans at a plurality of positions, the overall image of the examination is confirmed by a user such as an examiner. The update unit 40 generates an initial transformation matrix M based on the position information acquired during these scans and the result of recognition by the recognition unit 36. For example, when four cross-sections are scanned, the update unit 40 generates an initial transformation matrix M that is a 4×4 matrix. In the case where the overview scan scans a narrow range without switching the scanned cross-section and different parts are detected by detecting a part (for example, an organ), the update unit 40 generates the transformation matrix M by using the four positions of the detected part.

[0092] When the transformation matrix M is generated, the transformation unit 38 uses the transformation matrix M to transform the actual position Pr detected by the position sensor 14 into the correct position Pm. The display control unit 28 causes the display unit 22 to display the extracted information corresponding to the correct position Pm.

[0093] With reference to FIGS. 4 and 5, a display example of the extracted information will be described. FIGS. 4 and 5 show display examples of ultrasonic images and body marks.

[0094] The screen 48 shown in FIG. 4 is displayed on the display unit 22. When an ultrasonic image 50 is generated by ultrasonic scanning, the display control unit 28 displays the ultrasonic image 50 on the screen 48. For example, the ultrasonic image 50 is a B-mode image generated by scanning a certain scanning section. Of course, an image other than the B-mode image may be acquired and displayed as the ultrasonic image.

[0095] As shown in FIG. 4, the display control unit 28 displays the body mark 52 on the screen 48. The body mark 52 is a two-dimensional image or a three-dimensional image simulating the subject. Here, as an example, the body mark 52 is a three-dimensional image (that is, a 3D body mark).

[0096] For example, the display control unit 28 displays the inspection area 54 on the body mark 52. Further, the display control unit 28 displays the probe mark 56 on the body mark 52. The probe mark 56 is an image representing the ultrasonic probe 12. The display control unit 28 displays the probe mark 56 at the correct position corresponding to the current actual position detected by the position sensor 14 on the body mark 52. The current orientation of the ultrasonic probe 12 is also detected by the position sensor 14. The display control unit 28 expresses the detected orientation by the inclination of the probe mark 56. Further, the display control unit 28 displays the cross-section mark 58 on the body mark 52. The cross-section mark 58 is an example of information indicating the current scanning section, and is an image representing the correct cross-section corresponding to the current scanning section. In the example shown in FIG. 4, the body mark 52, the inspection area 54, the probe mark 56, and the cross-section mark 58 correspond to an example of the extracted information.

[0097] FIG. 5 shows an example of the display in the state where the inspection has progressed. The ultrasonic image 60 is displayed on the screen 48. Similar to the example shown in FIG. 4, the body mark 52, the inspection area 54, the probe mark 56, and the cross-section mark 58 are displayed on the screen 48. Similar to the example shown in FIG. 4, the probe mark 56 is displayed at the correct position corresponding to the current actual position of the ultrasonic probe 12. The cross-section mark 58 is an image representing the correct cross-section corresponding to the current scanning section.

[0098] The display control unit 28 displays the 3D model image 62 on the screen 48. The 3D model image 62 is a three-dimensional image representing the part to be inspected. The display control unit 28 superimposes and displays the ultrasonic image 60 on the 3D model image 62.

[0099] In addition, the display control unit 28 displays the cross-section marks 64, 66 on the body mark 52. The cross-section marks 64, 66 are an example of information indicating the unscanned cross-section, and are images representing the correct cross-section corresponding to the unscanned cross-section. As described above, the correct cross-sections (for example, 25 correct cross-sections) to be scanned by ultrasonic waves are pre-registered in the anatomical model. The scanned cross-section recognized by the recognition unit 36 is presumed to be the cross-section scanned by ultrasonic waves. In other words, the unscanned cross-section is a cross-section that has not been recognized by the recognition unit 36 among the plurality of correct cross-sections pre-registered in the anatomical model. The display control unit 28 displays, on the screen 48, as cross-section marks, the cross-section marks representing the scanned cross-sections not recognized by the recognition unit 36 as cross-section marks representing the unscanned cross-sections.

[0100] The display control unit 28 displays the cross-section mark 58 representing the current scanned cross-section and the cross-section marks 64, 66 representing the unscanned cross-sections in different display modes. For example, the display control unit 28 displays the cross-section mark 58 and the cross-section marks 64, 66 in different colors. Specifically, the display control unit 28 displays the cross-section mark 58 in blue and the cross-section marks 64, 66 in red. Of course, this display mode is just an example, and each cross-section mark may be displayed in a different color.

[0101] For example, the unscanned cross-section is spatially reset in advance, and the state where the position scanned by ultrasonic waves has been displayed is set. The positions that have not been in the displayed state are visualized by processes such as rendering. For example, the unscanned cross-sections are displayed as the cross-section marks 64, 66.

[0102] When there are remaining positions that have not been in the displayed state at the end of the inspection, the display control unit 28 may cause the display unit 22 to display a message indicating that there are unscanned cross-sections.

[0103] As another display example, the display control unit 28 may display the scanned area and the unscanned area on the body mark 52. For example, the display control unit 28 may display the scanned area and the unscanned area on the body mark 52 by making the display colors different between the scanned area and the unscanned area. Each area has the shape of an organ. Thereby, more perceptible information can be provided to a user such as a medical technician.

[0104]

[0103] When the subject's body position changes, the display control unit 28 may cause the display unit 22 to display the information before the body position change and the information after the body position change separately. The information before the body position change is information indicating a scanned cross-section that was unscanned before the body position change and information indicating a scanned cross-section that was scanned before the body position change. The information after the body position change is information indicating a scanned cross-section that is unscanned after the body position change and information indicating a scanned cross-section that was scanned after the body position change. For example, the display control unit 28 may make the display colors different between the information before the body position change and the information after the body position change. The display control unit 28 may switch the display and non-display of the information before the body position change according to a switching instruction from the user. The user can give an instruction to switch between display and non-display by operating the operation unit 32. The display control unit 28 may display the information before the body position change and the information after the body position change in the same color.

[0105] Another display example will be described with reference to FIG. 6. FIG. 6 shows a display example of an ultrasonic image and a body mark.

[0106] The ultrasonic image 68 and the body mark 52 are displayed on the screen 48. Also, the inspection area 54 and the probe mark 56 are displayed on the body mark 52. The probe mark 56 represents the current position and orientation of the ultrasonic probe 12. Also, the cross-section marks 70, 72 are displayed on the body mark 52. The cross-section mark 70 is an image representing the current scanning cross-section. The cross-section mark 72 is an image representing the scanned cross-section. For example, the probe mark 56 is displayed in yellow, the cross-section mark 70 is displayed in blue, and the cross-section mark 72 is displayed in green. By referring to these images, the user can confirm the current position of the ultrasonic probe 12, the current scanning cross-section, and the scanned cross-section. Note that, in addition to color, the probe mark and the cross-section mark may be displayed separately depending on lightness, chroma, hue, line type, etc. The same applies to other display examples.

[0107] Referring to FIG. 7, another display example will be described. FIG. 7 shows a display example of an ultrasonic image and a body mark.

[0108] Similar to the display example shown in FIG. 5, the ultrasonic image 60 and the body mark 52 are displayed on the screen 48. Also, the inspection area 54 and the probe mark 56 are displayed on the body mark 52. The probe mark 56 represents the current position and orientation of the ultrasonic probe 12. Also, the cross-section marks 58, 64, 66 are displayed on the body mark 52. The cross-section mark 58 is an image representing the current scanning cross-section. The cross-section marks 64, 66 are images representing unscanned cross-sections. For example, the cross-section marks 64, 66 are images representing the unscanned cross-sections among the cross-sections to be scanned (for example, the cross-section of the hepatic vein and the cross-section immediately below the diaphragm). The probe mark 56 is displayed in yellow, the cross-section mark 58 is displayed in blue, and the cross-section marks 64, 66 are displayed in red. By referring to these images, the user can confirm the current position of the ultrasonic probe 12, the current scanning cross-section, and the unscanned cross-sections.

[0109] The displayed extracted information may be displayed according to the orientation of the ultrasound probe 12, the orientation of the viewpoint, or the orientation of the correct cross section set on the anatomical model. For example, an image of the anatomical model viewed from a fixed position, an image of the anatomical model viewed from the same viewpoint as the generated ultrasound image, or an image of the anatomical model viewed from the same viewpoint as the standard cross section image may be displayed as the extracted information. When the user gives an instruction to switch, these images may be switched and displayed.

[0110] When the ultrasound examination is completed, the display control unit 28 may display information indicating unscanned scanning cross sections on the display unit 22. This allows the user to recognize areas that have not been scanned.

[0111] Another display example will be described with reference to Fig. 8. Fig. 8 shows a display example of an ultrasound image. As in the display example shown in Fig. 5, an ultrasound image 60 and a 3D model image 62 are displayed on the screen 48. The ultrasound image 60 is displayed superimposed on the 3D model image 62. The 3D model image 62 and the ultrasound image 60 superimposed on the 3D model image 62 are displayed as extracted information.

[0112] Note that standard three-dimensional ultrasound data, CT (Computed Tomography) data, or MRI (Magnetic Resonance Imaging) data may be used as the data of the anatomical model. As another example, past ultrasound data, CT data, or MRI data of a subject (e.g., a patient) to be examined may be used as the data of the anatomical model.

[0113] Each of the modified examples will be described below.

[0114] (Variation 1) The anatomical model may be created in advance for each examination site, and the data of the anatomical model for each examination site may be stored in advance in the storage unit 24. In this case, for each examination site, the correct cross-section and the correct position are registered in advance in the anatomical model. That is, an anatomical model for each individual examination site may be created in advance. The recognition unit 36 specifies the correct cross-section from the anatomical model for the site to be ultrasonically examined. That is, the recognition unit 36 specifies, from the anatomical model for the site to be ultrasonically examined, the correct cross-section that is estimated to match the scanned cross-section actually scanned by ultrasound. Also, for each examination site, an initial transformation matrix M may be determined in advance, and the initial transformation matrix M for each examination site may be stored in the storage unit 24. In this case, the conversion unit 38 converts the actual position Pr to the correct position Pm using the transformation matrix M for the site to be ultrasonically examined. The update unit 40 updates the transformation matrix M for the site to be ultrasonically examined by using the correct position Pm of the correct cross-section corresponding to the scanned cross-section recognized by the recognition unit 36 and the actual position Pr. The display control unit 28 causes the display unit 22 to display the extraction information obtained from the anatomical model for the site to be ultrasonically examined.

[0115] (Modification 2) The anatomical model may be created in advance for each measurement mode, and the data of the anatomical model for each measurement mode may be stored in advance in the storage unit 24. In this case, for each measurement mode, the correct cross-section and the correct position are registered in advance in the anatomical model. That is, an anatomical model for each individual inspection mode may be created in advance. The recognition unit 36 specifies the correct cross-section from the anatomical model for the inspection mode being executed. That is, the recognition unit 36 specifies, from the anatomical model for the inspection mode being executed, the correct cross-section that is estimated to match the scanned cross-section actually scanned by ultrasonic waves. Also, for each inspection mode, an initial transformation matrix M may be determined in advance, and the initial transformation matrix M for each inspection mode may be stored in the storage unit 24. In this case, the conversion unit 38 converts the actual position Pr to the correct position Pm using the conversion matrix M for the inspection mode being executed. The update unit 40 updates the conversion matrix M for the inspection mode being executed by using the correct position Pm of the correct cross-section corresponding to the scanned cross-section recognized by the recognition unit 36 and the actual position Pr. The display control unit 28 causes the display unit 22 to display the extraction information obtained from the anatomical model for the inspection mode being executed.

[0116] (Modification Example 3) An anatomical model may be created in advance for at least one of the body shape and body position of the subject. That is, an anatomical model may be created in advance for each body shape of the subject, or an anatomical model may be created in advance for each body position of the subject during the examination, or an anatomical model may be created in advance for each combination of the body shape and the body position.

[0117] An initial transformation matrix M may be determined in advance for at least one of the body shape and body position of the subject. That is, an initial transformation matrix M may be determined in advance for each body shape of the subject, and the initial transformation matrix M for each body shape may be stored in advance in the storage unit 24. An initial transformation matrix M may be determined for each body position of the subject, and the initial transformation matrix M for each body position may be stored in advance in the storage unit 24. An initial transformation matrix M may be determined in advance for each combination of the body shape and the body position of the subject, and the initial transformation matrix M for each combination of the body shape and the body position may be stored in advance in the storage unit 24.

[0118] For example, anatomical models for a plump body shape, a standard body shape, and a slender body shape are created in advance. Depending on the body shape of the subject, the depth and position from the body surface to the examination site (e.g., an organ) can vary. Therefore, depending on the body shape of the subject, the correct cross-section and the correct position can vary. To address this, anatomical models for individual body shapes are created in advance. For each body shape, the correct cross-section and the correct position are registered in advance in the anatomical model. That is, anatomical models for individual body shapes are created in advance, and the data of the anatomical models for each body shape are stored in advance in the storage unit 24. The recognition unit 36 identifies the correct cross-section from the anatomical model for the body shape of the subject. That is, the recognition unit 36 identifies, from the anatomical model for the body shape of the subject, the correct cross-section that is estimated to match the cross-section actually scanned by ultrasound. Also, for each body shape, an initial transformation matrix M may be determined in advance, and the initial transformation matrix M for each body shape may be stored in the storage unit 24. In this case, the conversion unit 38 converts the actual position Pr to the correct position Pm using the transformation matrix M for the body shape of the subject. The update unit 40 updates the transformation matrix M for the body shape of the subject by using the correct position Pm of the correct cross-section corresponding to the cross-section recognized by the recognition unit 36 and the actual position Pr. The display control unit 28 causes the display unit 22 to display the extraction information obtained from the anatomical model for the body shape of the subject.

[0119] For example, an anatomical model for the supine position, an anatomical model for the lateral position, and an anatomical model for the sitting position are created in advance. Depending on the subject's body position, the depth and position from the body surface to the examination site may change. Therefore, depending on the subject's body position, the correct cross-section and the correct position may change. To address this, anatomical models for individual body positions are created in advance. For each body position, the correct cross-section and the correct position are registered in advance in the anatomical model. That is, anatomical models for individual body positions are created in advance, and the data of the anatomical models for each body position are stored in the storage unit 24 in advance. The recognition unit 36 identifies the correct cross-section from the anatomical model for the subject's body position. That is, the recognition unit 36 identifies, from the anatomical model for the subject's body position, the correct cross-section that is estimated to match the scanned cross-section actually scanned by ultrasound. Also, for each body position, an initial transformation matrix M may be determined in advance, and the initial transformation matrix M for each body position may be stored in the storage unit 24. In this case, the transformation unit 38 uses the transformation matrix M for the subject's body position to transform the actual position Pr into the correct position Pm. The update unit 40 updates the transformation matrix M for the subject's body position by using the correct position Pm of the correct cross-section corresponding to the scanned cross-section recognized by the recognition unit 36 and the actual position Pr. The display control unit 28 causes the display unit 22 to display the extraction information obtained from the anatomical model for the subject's body position.

[0120] Similarly, when anatomical models are created for each combination of body shape and body position, by using the anatomical model corresponding to the combination of the subject's body shape and body position, position transformation, update of the transformation matrix M, and display of extraction information are performed.

[0121] Here, the processing by the setting unit 42 and the estimation unit 44 will be described in detail.

[0122] The setting unit 42 sets an anatomical model corresponding to at least one of the body shape and body position of the subject to be ultrasonically examined as the anatomical model used for conversion. The recognition unit 36 identifies a correct cross-section estimated to match the actually ultrasonically scanned cross-section from the anatomical model set by the setting unit 42. The conversion unit 38 converts the actual position Pr to the correct position Pm using the conversion matrix M defined by using the anatomical model set by the setting unit 42. The update unit 40 updates the conversion matrix M by using the anatomical model set by the setting unit 42. The display control unit 28 causes the display unit 22 to display the extraction information obtained from the anatomical model set by the setting unit 42.

[0123] For example, at least one of the body shape and body position of the subject is specified by the user. The setting unit 42 sets an anatomical model corresponding to the at least one specified by the user as the anatomical model used for conversion. For example, the user determines the body shape and body position of the subject to be ultrasonically examined and operates the operation unit 32 to specify at least one of the body shape and body position of the subject.

[0124] As another example, the setting unit 42 may estimate at least one of the body shape and body position of the subject based on an image (for example, a moving image or a still image) generated by photographing the subject to be ultrasonically examined with a camera, and set an anatomical model corresponding to the estimation result as the anatomical model used for conversion. A known technique is used as the technique for detecting the body shape and body position of the subject from the image. For example, the setting unit 42 estimates the body shape and body position of the subject represented in the image by using image recognition technology. Also, when there is a change in the body position of the subject during the examination, the setting unit 42 sets an anatomical model corresponding to the changed body position as the anatomical model used for conversion. As the technique for estimating the body shape and body position, AI, machine learning, pattern matching, or the like may be used.

[0125] As yet another example, the setting unit 42 may receive subject identification information for identifying a subject, and set, as the anatomical model to be used for conversion, an anatomical model corresponding to the body shape indicated by the body shape information associated with the subject identification information.

[0126] For example, before the ultrasonic examination is performed, subject identification information (such as a patient ID, etc.) of the subject to be examined by the ultrasonic examination is input to the ultrasonic diagnostic apparatus 10. The user may input the subject identification information to the ultrasonic diagnostic apparatus 10 by operating the operation unit 32. When a tag on which the subject identification information is described is attached to the wrist or the like of the subject, the subject identification information described on the tag may be read and the subject identification information may be input to the ultrasonic diagnostic apparatus 10. For example, the encoded subject identification information (such as a barcode or a two-dimensional code) is described on the tag, and the encoded subject identification information is read. The subject identification information may be input to the ultrasonic diagnostic apparatus 10 from an external device such as a server via a communication path such as a network.

[0127] The body shape information indicating the body shape of the subject is associated with the subject identification information. The body shape information may be included in the subject identification information, or may be associated with the subject identification information and stored in an external device such as a server. When the body shape information is stored in the external device, when the setting unit 42 receives the input subject identification information, the setting unit 42 acquires the body shape information stored in the external device associated with the input subject identification information. The setting unit 42 sets, as the anatomical model to be used for conversion, an anatomical model corresponding to the body shape indicated by the body shape information.

[0128] The estimation unit 44 estimates at least one of the body shape and the body position of the subject based on the position and orientation of the ultrasonic probe 12. The position and orientation of the ultrasonic probe 12 are detected by the position sensor 14. The setting unit 42 sets, as the anatomical model to be used for conversion, an anatomical model corresponding to the result of the estimation by the estimation unit 44.

[0129] For example, when the subject is a subject with an overweight body shape, compared to a subject with a slender body shape, the ultrasonic probe 12 may be pressed more strongly against the body surface of the subject for inspection. As a result, compared to the case of inspecting a subject with a slender body shape, the ultrasonic probe 12 is pushed deeper into the body. Therefore, even when performing the same ultrasonic examination, the actual position Pr of the ultrasonic probe 12 changes according to the body shape of the subject. Therefore, based on the actual position Pr of the ultrasonic probe 12, the body shape of the subject can be estimated.

[0130] Also, according to the body position such as the supine position, the lateral position, or the sitting position, the position and orientation of the ultrasonic probe 12 on the body surface of the subject change. Therefore, based on the actual position Pr of the ultrasonic probe 12, the body position of the subject can be estimated.

[0131] For example, the user sequentially places the ultrasonic probe 12 at reference locations of the subject (e.g., the head, abdomen, back, toes, fingertips, etc.), and the position sensor 14 detects the position and orientation of the ultrasonic probe 12 at each reference location. The estimation unit 44 estimates the size, thickness, and orientation of the subject based on the position and orientation of the ultrasonic probe 12 at each reference location. Depending on the body shape and body position of the subject, the size, thickness, and orientation of the subject estimated from the position and orientation of the ultrasonic probe 12 at each reference location are different. Therefore, based on the position and orientation of the ultrasonic probe 12 at each reference location, the body shape and body position of the subject can be estimated.

[0132] The estimation unit 44 may estimate at least one of the body shape and body position of the subject based on the ultrasonic image. For example, the estimation unit 44 estimates at least one of the body shape and body position of the subject based on the shape, position, and number of structures such as the parts shown in the ultrasonic image.

[0133] Depending on the body shape of the subject, the shape and position of the structure of a part or the like may vary. Therefore, the body shape of the subject can be estimated based on the shape and position of the structure represented in the ultrasonic image. Also, depending on the body position of the subject, the shape and position of the structure of a part or the like may vary. Therefore, the body position of the subject can be estimated according to the shape and position of the structure represented in the ultrasonic image.

[0134] For example, when a reference part of the subject (for example, an organ in the abdomen) is scanned by ultrasonic waves, an ultrasonic image representing the reference part is generated. For example, ultrasonic images representing the aorta, spine, fat layer, etc. are generated. The estimation unit 44 applies a recognition process to the ultrasonic image to measure the position of the organ (for example, the depth from the body surface), the number of organs, and the size of the organ (for example, thickness) represented in the ultrasonic image. The estimation unit 44 estimates the body shape and body position of the subject based on the measurement results. For example, the organs of a subject with a plump body shape are located deeper from the body surface than the organs of a subject with a slender body shape. Therefore, the body shape of the subject can be estimated based on the position of the organ (for example, the depth from the body surface) represented in the ultrasonic image. Also, the fat layer is thinner in the lying position than in the sitting position. Therefore, the body position of the subject can be estimated based on the thickness of the fat layer represented in the ultrasonic image.

[0135] When a change occurs in the body position of the subject, the update unit 40 may newly create a transformation matrix M corresponding to the changed body position. When a change in the body position of the subject is detected, the update unit 40 resets the transformation matrix M that has been updated so far, and based on the actual position Pr detected after the body position has changed and the correct position Pm corresponding to the actual position Pr, newly creates the transformation matrix M. After that, the update unit 40 continues to update the newly created transformation matrix M. For example, the estimation unit 44 can detect a change in the body position of the subject based on an image (for example, a moving image or a still image) generated by photographing the subject with a camera. As another example, when the actual position Pr detected by the position sensor 14 and the scanning cross-section do not match the current transformation matrix M, the estimation unit 44 may determine that the body position of the subject has changed.

[0136] The memory control unit 30 may associate the extracted information with the information indicating the subject's body position for each body position of the subject and store the same in the storage unit 24. For example, when the subject's body position changes, the memory control unit 30 associates the information indicating the body position before the change with the extracted information before the body position changes and stores the same in the storage unit 24. When the user designates the body position before the change by operating the operation unit 32, the display control unit 28 causes the display unit 22 to display the extracted information associated with the information indicating the body position before the change. For example, the display control unit 28 causes the display unit 22 to display the extracted information before the body position changes as past extracted information. The display control unit 28 may cause the display unit 22 to display the extracted information after the body position changes (for example, the extracted information corresponding to the current body position) and the extracted information before the body position changes (for example, past extracted information) side by side. In this case, the display control unit 28 causes the display unit 22 to display the extracted information after the body position changes and the extracted information before the body position changes separately. For example, the display control unit 28 causes the display unit 22 to display each extracted information by changing the brightness, saturation, hue, or line type or the like between the extracted information corresponding to the current body position and the past extracted information. The display control unit 28 may cause the display unit 22 to display the scanned cross-section and the unscanned cross-section separately. Further, when the user instructs to switch the extracted information by operating the operation unit 32, the display control unit 28 may switch the extracted information according to the instruction and cause the display unit 22 to display the same. For example, the display of the extracted information corresponding to the current body position and the past extracted information may be switched.

[0137] The image generation unit 18, the display processing unit 20, the analysis unit 34, and the control unit 26 can be realized by using hardware resources such as a processor or an electronic circuit. In the realization, devices such as a memory may be used as necessary. Further, the image generation unit 18, the display processing unit 20, the analysis unit 34, and the control unit 26 may be realized by, for example, a computer. That is, all or part of the image generation unit 18, the display processing unit 20, the analysis unit 34, and the control unit 26 may be realized by the cooperation of hardware resources such as a CPU (Central Processing Unit) and a memory included in the computer, and software (program) that defines the operations of the CPU and the like. The program is stored in the storage device of the ultrasonic diagnostic apparatus 10 or another storage device via a recording medium such as a CD or a DVD, or via a communication path such as a network. As another example, the image generation unit 18, the display processing unit 20, the analysis unit 34, and the control unit 26 may be realized by a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or the like. Of course, a GPU (Graphics Processing Unit) or the like may be used. The image generation unit 18, the display processing unit 20, the analysis unit 34, and the control unit 26 may be realized by a single device or by a plurality of devices.

[0138] Note that the respective functions of the image generation unit 18, the display processing unit 20, the analysis unit 34, and the control unit 26 may be executed by a device other than the ultrasonic diagnostic apparatus 10 (for example, a personal computer, a server, or the like).

Description of Reference Numerals

[0139] 28 Display control unit, 36 Recognition unit, 38 Conversion unit, 40 Update unit, 42 Setting unit, 44 Estimation unit.

Claims

1. An acquisition unit that acquires position information of an ultrasonic probe, A recognition unit that recognizes a scanning cross-section where ultrasonic waves are scanned based on an ultrasonic image acquired by scanning with the ultrasonic probe, Using an anatomical model in which a correct cross-section where an ultrasonic examination is to be performed and the correct position of the correct cross-section are registered, according to a conversion rule, the position indicated by the position information acquired by the acquisition unit is associated with the anatomical model. A conversion unit that converts to the correct position, A display control unit that causes a display to display extraction information related to an ultrasonic examination corresponding to the correct position converted by the conversion unit, An update unit that updates the conversion rule by using the correct position of the correct cross-section corresponding to the scanning cross-section recognized by the recognition unit and the position indicated by the position information acquired by the acquisition unit, An ultrasonic diagnostic apparatus including the above.

2. In the ultrasonic diagnostic apparatus according to Claim 1, The conversion according to the conversion rule is a conversion using a conversion matrix, The update unit updates the conversion matrix by using the position indicated by the position information acquired by the acquisition unit and the correct position of the correct cross-section, An ultrasonic diagnostic apparatus characterized by the above.

3. In the ultrasonic diagnostic apparatus according to Claim 1, For each examination site, a correct cross-section and a correct position are registered in the anatomical model, An ultrasonic diagnostic apparatus characterized by the above.

4. In the ultrasonic diagnostic apparatus according to Claim 1, Further including a setting unit that sets, as the anatomical model used for conversion, an anatomical model corresponding to at least one of the body shape and body position of a subject to be examined by ultrasonic examination, An ultrasonic diagnostic apparatus characterized by the above.

5. In the ultrasonic diagnostic apparatus according to Claim 4, At least one of the body shape and body position of the subject is specified by the user, and the setting unit sets, as the anatomical model used for conversion, an anatomical model corresponding to the at least one specified by the user. An ultrasonic diagnostic apparatus characterized by the above. **Claim 6** In the ultrasonic diagnostic apparatus according to claim 4, the setting unit estimates at least one of the body shape and body position of the subject based on an image generated by photographing the subject with a camera, and sets, as the anatomical model used for conversion, an anatomical model corresponding to the estimation result. An ultrasonic diagnostic apparatus characterized by the above. **Claim 7** In the ultrasonic diagnostic apparatus according to claim 4, the setting unit receives subject identification information for identifying the subject, and sets, as the anatomical model used for conversion, an anatomical model corresponding to the body shape indicated by the body shape information associated with the subject identification information. An ultrasonic diagnostic apparatus characterized by the above. **Claim 8** In the ultrasonic diagnostic apparatus according to claim 4, the apparatus further includes an estimation unit that estimates at least one of the body shape and body position of the subject based on the position of the ultrasonic probe, and the setting unit sets, as the anatomical model used for conversion, an anatomical model corresponding to the estimation result by the estimation unit. An ultrasonic diagnostic apparatus characterized by the above. **Claim 9** In the ultrasonic diagnostic apparatus according to claim 4, the apparatus further includes an estimation unit that estimates at least one of the body shape and body position of the subject based on the ultrasonic image, and the setting unit sets, as the anatomical model used for conversion, an anatomical model corresponding to the estimation result by the estimation unit. An ultrasonic diagnostic apparatus characterized by the above. **Claim 10** In the ultrasonic diagnostic apparatus according to claim 4, when a change occurs in the body position of the subject, the updating unit newly creates a conversion rule according to the changed body position. An ultrasonic diagnostic apparatus characterized by the above.

11. In the ultrasonic diagnostic apparatus according to claim 1, the extracted information includes at least one of information indicating the position of the ultrasonic probe, information indicating the orientation of the ultrasonic probe, information indicating the current scanning range by ultrasound, information indicating the past scanning range by ultrasound, and information indicating the unscanned range. An ultrasonic diagnostic apparatus characterized by the above.

Images