JP2006218210A - Ultrasonic diagnostic apparatus, ultrasonic image generating program and ultrasonic image generating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic apparatus which can extract and display a desired three-dimensional image by a simple method. <P>SOLUTION: An ROI marker 23 is set to follow an image 21 of a fetus on a tomogram 20. The ROI marker 23 indicates a region of interest (ROI) and is set obliquely to an XY orthogonal coordinates system of the tomogram data. An image generating range calculating section acquires the range which includes the range indicated by the ROI marker 23 and is parallel to the XY orthogonal coordinates system to let the range be an image generating range 25. A voxel data generating section generates the voxel data by executing the re-sampling processing using the tomogram data included in the image generating range 25. An image generating section generates the three-dimensional image data on the basis of the voxel data and an image extracting section makes a pixel value of the coordinate in the range other than the range of interest be [0]. Thereby, the three-dimensional image following a shape of the fetus is displayed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for generating a three-dimensional image by an ultrasonic diagnostic apparatus and extracting a three-dimensional image in a region of interest (ROI).

  Image diagnostic apparatuses such as an X-ray diagnostic apparatus, an X-ray CT apparatus, an MRI apparatus, and an ultrasonic diagnostic apparatus are used as an apparatus for imaging the inside of a subject. Among the above-mentioned diagnostic imaging apparatuses, the ultrasonic diagnostic apparatus is small and non-invasive, and does not have X-ray exposure on the subject. Therefore, it is an indispensable apparatus especially for fetal growth diagnosis. .

  The ultrasonic probe provided in the ultrasonic diagnostic apparatus has ultrasonic transducers arranged one-dimensionally in the scanning direction, transmits and receives ultrasonic waves for electronic delay control, and produces a tomographic image (2 It is common to collect (dimensional images).

  In recent years, not only two-dimensional tomographic imaging but also three-dimensional imaging and display have been put into practical use and are being used in clinical settings (for example, Patent Document 1). For example, a tomographic image data (B-mode image data) in a direction perpendicular to the scan plane (oscillation direction) is collected by mechanically oscillating a one-dimensional ultrasonic probe having an oscillation mechanism. Thereby, a three-dimensional image is generated.

  For example, when a plurality of tomographic image data (B-mode image data) is acquired by swinging an ultrasonic transducer, three-dimensional information is obtained by performing interpolation processing called resampling on the plurality of tomographic image data. 3D volume data (voxel data) is generated, and the voxel data is subjected to processing such as volume rendering to generate 3D image data. Since the collected tomographic image data are on different coordinate systems, it is necessary to reconstruct voxel data represented by a common coordinate system. The position and angle of the ultrasonic probe are measured with a position sensor, and voxel values on a common coordinate system are interpolated by pixel values of nearby tomographic image data based on the position and angle, and voxel data is obtained. Generate (resampling process).

  Furthermore, in order to shorten the processing time, a three-dimensional image of only a region of interest that is desired to be displayed as a three-dimensional image is extracted and displayed. In this case, a region of interest (ROI) indicating a range to be displayed by extracting an image is set, data in the region of interest (ROI) is extracted from the voxel data, and a three-dimensional image in the region of interest (ROI) is extracted. Is generated.

  Observation of the fetus in the mother's body is performed in the obstetrics using the ultrasonic diagnostic apparatus capable of collecting the above three-dimensional images. Even when a fetus is observed by displaying a 3D image, a 3D image of the fetus as a region of interest is extracted and displayed. Conventionally, when displaying a 3D image of a fetus, a region of interest (ROI) for the 3D image is included so that the fetal image is included while observing the fetal image included in the 2D tomographic image. After that, data in the region of interest (ROI) is extracted from the voxel data generated by the resampling process, and a three-dimensional image in the region of interest (ROI) is generated. As a result, a three-dimensional image including the fetal image is generated and displayed.

  The setting of the region of interest (ROI) will be described with reference to FIG. FIG. 6 is a diagram for explaining a method of setting a region of interest (ROI) in the prior art, FIG. 6A is a diagram showing a tomogram as two-dimensional information, and FIG. It is a figure which shows the tomogram for demonstrating the setting of a cutting plane.

  For example, as shown in FIG. 6A, a tomographic image 20 including a fetal image 21 is displayed on the monitor screen of the display device, and the operator observes the tomographic image 20 while observing the tomographic image 20. A rectangular ROI marker 23 representing a region of interest (ROI) is designated so as to be included. The rectangular ROI marker 23 is set in parallel to the XY orthogonal coordinate axes for representing the tomographic image 20. FIG. 6A shows an image 22 of an amniotic membrane enveloping the fetus. Thus, when the rectangular ROI marker 23 parallel to the XY orthogonal coordinate axes is set, voxel data is generated by performing resampling processing on a plurality of tomographic image data, and the ROI marker 23 is generated from the voxel data. The data in the region of interest (ROI) represented by (3) is extracted to generate a three-dimensional image in the region of interest (ROI).

  A three-dimensional image included in the region of interest (ROI) represented by the ROI marker 23 set on the two-dimensional image is generated, and the three-dimensional image is displayed on the monitor screen of the display device. This three-dimensional image includes a three-dimensional image of the fetus, but also includes a three-dimensional image of the amniotic membrane that wraps the fetus and is displayed on the monitor screen. For example, when it is desired to observe a three-dimensional image of the fetus from the direction of arrow A, the display direction of the three-dimensional image is changed so that the direction of arrow A is displayed facing the front. However, since the fetus is enveloped in the amniotic membrane, if the display direction of the 3D image is changed so that the direction of the arrow A faces the front, the amniotic membrane image exists on the near side of the 3D image of the fetus. The image of the amniotic membrane becomes a shield, and it becomes impossible to observe the three-dimensional image of the fetus to be observed.

  That is, in the two-dimensional image, since the rectangular ROI marker 23 parallel to the XY orthogonal coordinate axes is set and the three-dimensional image included in the range is extracted, in addition to the three-dimensional image of the fetus to be observed, An image of the amniotic membrane serving as a shield was also extracted, and as a result, only a three-dimensional image of the fetus could not be extracted and displayed. Usually, since the image of the fetus is displayed obliquely with respect to the XY orthogonal coordinate axes, if a rectangular ROI marker 23 parallel to the XY orthogonal coordinate axes is set so that the fetus is included, the part other than the fetus is also in the region of interest. It was included in (ROI), and only a three-dimensional image of the fetus could not be extracted and displayed.

  Therefore, in order to remove the unnecessary image and display only the three-dimensional image of the fetus, after setting the region of interest (ROI), a predetermined plane (cut plane) 24 is formed as shown in FIG. It was set along the fetus. When a three-dimensional image included in the region of interest (ROI) represented by the ROI marker 23 is extracted, it is included in the region 23B outside the region 23A including the fetal image with the cutting plane 24 as a boundary. The image was removed. In the removed area, for example, the pixel value is set to “0”. Accordingly, even when the display direction of the three-dimensional image is changed so that the direction of the arrow A is displayed facing the front, the three-dimensional image included in the region 23A is removed. The image of the amniotic membrane contained in is not displayed, and a three-dimensional image of the fetus can be observed from the direction of arrow A.

JP 2001-190552 A

  However, in order to set the cutting plane 24 in order to remove the image of the amniotic membrane serving as a shield, the cutting plane 24 is displayed on the tomographic image 20, and the vertical direction (Y direction) and the horizontal direction (X direction) are displayed. ) And the angle with respect to the fetus must be changed to set the cutting plane 24. This operation needs to be performed by the operator. In order to display the three-dimensional image of the fetus by removing the shielding object, the cutting plane 24 is set so as to be parallel to the fetus displayed obliquely. Although it is necessary, since the setting is a very complicated operation, it is not possible to simply extract and display only a target three-dimensional image (in the above example, a three-dimensional image of a fetus). Furthermore, since setting of the cutting plane 24 requires skilled skills, the target image (in the above example, the three-dimensional image of the fetus) cannot be displayed with high accuracy in a short time, and the diagnosis time may be prolonged. . Moreover, since the setting of the cutting plane 24 depends on the skill of the operator, there is a possibility that the operator cannot set the cutting plane 24 so that only a three-dimensional image of the fetus is displayed.

  The present invention solves the above problem, obtains an image generation range including a region of interest and parallel to a coordinate axis representing a tomographic image, extracts a three-dimensional image included in the image generation range, and extracts the three-dimensional image. Apparatus that can easily extract and display a three-dimensional image included in a region of interest by removing and displaying an image other than the image included in the region of interest from the image It is an object to provide a program and an ultrasonic image generation method.

  The invention according to claim 1 is a scanning unit that collects a plurality of tomographic image data in the swinging direction by performing transmission and reception of ultrasonic waves while swinging the ultrasonic transducer in a direction orthogonal to the scan plane; A region-of-interest setting means for setting a region of interest for the tomographic image data; an image generation range calculating unit that circumscribes the region of interest and obtains an image generation range parallel to the coordinate axis of the tomographic image data; Volume data generating means for generating three-dimensional volume data by stacking data included in the image generation range of the tomographic image data in the swing direction for all of the plurality of tomographic image data collected in 3D image generation means for generating 3D image data based on the data and extracting 3D image data included in the region of interest from the 3D image data When a display means for displaying the 3-dimensional image in which the extracted, an ultrasonic diagnostic apparatus characterized by having a.

  For example, when a region of interest (ROI) along the direction of the fetus is set on the tomographic image when a three-dimensional image of the fetus is to be observed for observation, the image generation range calculation means circumscribes the region of interest. A range is obtained, and the range is set as an image generation range. The image generation range is obtained so as to be parallel to the coordinate axis for representing the tomographic image. For example, when the tomographic image is on Cartesian coordinates, a rectangular image generation range that is parallel to the Cartesian coordinate axes is obtained. If the region of interest is set along the orientation when the orientation of the fetus is oblique to the Cartesian coordinate, an image generation range that circumscribes the region of interest and is parallel to the Cartesian coordinate axis is obtained. . The volume data generation means generates three-dimensional volume data by performing resampling processing using the tomographic image data included in the image generation range. The three-dimensional image generation unit extracts data included in the region of interest when generating the three-dimensional image data from the three-dimensional volume data. As a result, a three-dimensional image along the shape of the fetus can be generated and displayed. Therefore, unlike the prior art, there is no need to specify a cutting plane in order to remove an unnecessary image, so that a desired three-dimensional image can be extracted and displayed with a simple operation. The region of interest (ROI) is designated by the operator, and the position and shape can be arbitrarily changed.

  The invention according to claim 2 is the ultrasonic diagnostic apparatus according to claim 1, wherein the coordinate axis is an orthogonal coordinate axis, the set region of interest has a rectangular shape, and the image generation range The calculating means obtains a rectangular image generation range in which each side is in contact with each vertex of the rectangular region of interest and parallel to the orthogonal coordinate axis.

  The invention according to claim 3 is the ultrasonic diagnostic apparatus according to claim 1 or 2, wherein the three-dimensional image generation means is within the image generation range and the region of interest. The three-dimensional image data included in the region of interest is extracted by removing the three-dimensional image in a range other than.

  A fourth aspect of the present invention is the ultrasonic diagnostic apparatus according to any one of the first to third aspects, wherein the three-dimensional image generation means is within the image generation range and the region of interest. The three-dimensional image data included in the region of interest is extracted by setting the pixel value of the three-dimensional image data included in the range other than “0” to “0”.

  The invention according to claim 5 is an ultrasonic diagnostic apparatus that collects a plurality of tomographic image data in a swinging direction by transmitting and receiving ultrasonic waves while swinging an ultrasonic transducer in a direction orthogonal to the scan plane. A region-of-interest setting function for setting a region of interest for the tomographic image data; an image generation range calculating function for obtaining an image generation range circumscribing the region of interest and parallel to the coordinate axis of the tomographic image data; A volume data generation function for generating three-dimensional volume data by stacking data included in the image generation range of the tomographic image data in the swing direction for all of the plurality of tomographic image data collected in the moving direction; 3D image generation that generates 3D image data based on 3D volume data and extracts 3D image data included in the region of interest from the 3D image data Noh, an ultrasonic image generating program, characterized in that to execute a display function of displaying on the display means the three-dimensional image the extracted.

  The invention according to claim 6 is based on a plurality of tomographic image data collected in the swing direction by transmitting and receiving ultrasonic waves while swinging the ultrasonic transducer in a direction orthogonal to the scan plane. An ultrasonic image generation method for generating dimensional image data, wherein a region-of-interest setting unit sets a region of interest for the tomographic image data, and an image generation range calculation unit includes a region of interest in the region of interest. An image generation range calculating step for obtaining an image generation range that circumscribes and parallel to the coordinate axis of the tomographic image data, and a volume data generating unit for the tomographic image data for all of the plurality of tomographic image data collected in the swing direction Data generation step for generating three-dimensional volume data by stacking data included in the image generation range in the swing direction, and three-dimensional image generation means 3D image generation step of generating 3D image data based on the 3D volume data and extracting 3D image data included in the region of interest from the 3D image data. It is an ultrasonic image generation method.

  According to the present invention, it is possible to generate and display a three-dimensional image along the shape of the diagnostic region desired to be observed. Further, unlike the prior art, it is not necessary to set a cutting plane again, so that the operation becomes simple and the target three-dimensional image can be displayed accurately in a short time.

  Hereinafter, an ultrasonic diagnostic apparatus, an ultrasonic image generation program, and an ultrasonic image generation method according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5.

(Constitution)
The configuration of the ultrasonic diagnostic apparatus according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a schematic configuration of an ultrasonic diagnostic apparatus according to an embodiment of the present invention.

  An ultrasonic diagnostic apparatus according to an embodiment of the present invention includes an ultrasonic probe 1, a transmission / reception unit 2, a signal processing unit 3, a DSC 4, a three-dimensional image generation unit 5, a display control unit 6, a display device 7, and a region of interest (ROI). A setting unit 8 and an operation unit 9 are provided.

  The ultrasonic probe 1 is composed of a one-dimensional ultrasonic probe in which ultrasonic transducers that transmit and receive ultrasonic waves are arranged one-dimensionally in the scanning direction. The reflected wave is received as an echo signal. The one-dimensional ultrasonic probe is provided with a motor as a swinging mechanism, and the ultrasonic transducer is swung in a direction (swinging direction) perpendicular to the scanning direction by the motor, and a plurality of swinging directions are provided. 3D image data is generated by collecting the tomographic image data and using these tomographic image data. In other words, the ultrasonic transducer is swung in a direction perpendicular to the scan plane, and a plurality of pieces of tomographic image data in the swing direction are collected. Further, as the ultrasonic probe 1, a two-dimensional ultrasonic probe in which ultrasonic transducers are arranged in a matrix (lattice) may be used. In the case of a two-dimensional ultrasonic probe, ultrasonic waves are transmitted and received three-dimensionally by scanning, and three-dimensional data having a shape spreading radially from the surface of the probe is received as an echo signal.

  The transmission / reception unit 2 includes a transmission unit and a reception unit, supplies an electrical signal to the ultrasonic probe 1 to generate an ultrasonic wave, and receives an echo signal received by the ultrasonic probe 1.

  The transmission unit in the transmission / reception unit 2 includes a clock generation circuit, a transmission delay circuit, and a pulsar circuit (not shown). The clock generation circuit is a circuit that generates a clock signal that determines the transmission timing and transmission frequency of the ultrasonic signal. The transmission delay circuit is a circuit that performs transmission focus with a delay when transmitting ultrasonic waves. The pulsar circuit incorporates pulsars corresponding to the number of individual paths (channels) corresponding to each ultrasonic transducer, generates a drive pulse at a delayed transmission timing, and each ultrasonic transducer of the ultrasonic probe 1. To supply.

  The reception unit in the transmission / reception unit 2 includes a preamplifier circuit, an A / D conversion circuit, and a reception delay / addition circuit (not shown). The preamplifier circuit amplifies the echo signal output from each ultrasonic transducer of the ultrasonic probe 1 for each reception channel. The A / D converter circuit A / D converts the amplified echo signal. The reception delay / adder circuit gives a delay time necessary for determining the reception directivity to the echo signal after A / D conversion, and adds the delay time. By the addition, the reflection component from the direction according to the reception directivity is emphasized. The signal added by the transmission / reception circuit 3 is referred to as “RF data (or raw data)”.

  The signal processing unit 3 includes a B mode processing circuit, a Doppler processing circuit, and a color mode processing circuit. The RF data output from the transmission / reception unit 2 is subjected to predetermined processing in any processing circuit.

  The B-mode processing circuit visualizes echo amplitude information and generates B-mode ultrasonic raster data from the echo signal. Specifically, bandpass filter processing is performed on the RF data, and then the envelope of the output signal is detected, and compression processing by logarithmic transformation is performed on the detected data. In addition, processing such as edge enhancement may be performed. Data generated by the B-mode processing circuit is referred to as B-mode ultrasonic raster data.

  The Doppler processing circuit includes a phase detection circuit, an FFT operation circuit, and the like. The Doppler shift frequency component is extracted from the RF data, and further subjected to FFT processing and the like to generate data having blood flow information.

  The color mode processing circuit visualizes the moving blood flow information and generates color ultrasonic raster data. Blood flow information includes information such as speed, dispersion, and power, and blood flow information is obtained as binarized information. Specifically, the color mode processing circuit includes a phase detection circuit, an MTI filter, an autocorrelator, and a flow velocity / dispersion calculator. In this color mode processing circuit, high-pass filter processing (MTI filter processing) for separating tissue signals and blood flow signals is performed, and blood flow information such as blood flow velocity, dispersion, and power is obtained by autocorrelation processing. Ask for multiple points. In addition, non-linear processing for reducing and reducing tissue signals may be performed.

  A DSC 4 (Digital Scan Converter) converts ultrasonic raster data into data represented by orthogonal coordinates in order to obtain an image represented by an orthogonal coordinate system. The DSC 4 converts the signal-processed data represented by the scanning line signal sequence output from the signal processing unit 3 described above into coordinate system data based on the spatial information (scan conversion process). That is, the scanning method is converted by reading out in synchronization with the standard television scanning so that the signal sequence synchronized with the ultrasonic scanning can be displayed on the display device 7 of the television scanning method.

  When scan conversion processing is performed on the data output from the B-mode processing circuit, tomographic image data (B-mode image data) representing the tissue shape of the subject as two-dimensional information is generated. The two-dimensional information tomographic image data (B-mode image data) is output to the display device 7 via the display control unit 6 and displayed as a two-dimensional tomographic image on the monitor screen of the display device 7 as a light and shade.

  Further, the DSC 4 is configured to include an image generation range calculation unit 41 and a voxel data generation unit 42, and performs three-dimensional volume data (voxel) by performing an interpolation process called resampling on the generated plurality of tomographic image data. Data). The image generation range calculation unit 41 circumscribes a region of interest (ROI) indicated by the ROI marker output from the ROI setting unit 8 and generates a rectangular range parallel to the XY orthogonal coordinate axes for representing a tomographic image. This parallel rectangular range is the image generation range. The voxel data generation unit 42 receives image generation range data indicating a rectangular range from the image generation range calculation unit 41 and performs an interpolation process called resampling on a plurality of tomographic image data. At this time, the voxel data generation unit 42 resamples the data in the rectangular range based on the image generation range data indicating the rectangular range, and generates voxel data corresponding to the rectangular range. Specific processing contents of the DSC 4 will be described later.

  The 3D image generation unit 5 performs volume rendering on the voxel data output from the DSC 4 to generate 3D image data. The three-dimensional image data generated by the three-dimensional image generation unit 5 is output to the display device 7 via the display control unit 6 and displayed. When a region of interest (ROI) indicating a region where an ultrasonic image is to be generated is set by the operator and ROI marker data is sent from the ROI setting unit 8, the 3D image generation unit 5 is within the range indicated by the ROI marker. Is extracted to generate a three-dimensional image of the region of interest (ROI).

  Specifically, the three-dimensional image generation unit 5 includes an image generation unit 51 and an image extraction unit 52. The image generation unit 51 receives voxel data from the voxel data generation unit 42 of the DSC 4 and generates three-dimensional image data by volume rendering processing. When voxel data corresponding to a rectangular range is output from the voxel data generation unit 42, three-dimensional image data within the rectangular range is generated. The image extraction unit 52 removes an image outside the region of interest (ROI) indicated by the ROI marker from the three-dimensional image data generated by the image generation unit 51. That is, the image extraction unit 52 sets the pixel value of the coordinates outside the region of interest (ROI) indicated by the ROI marker to “0”. Then, the three-dimensional image generation unit 5 outputs the three-dimensional image data in which the pixel value of the coordinates outside the region of interest (ROI) is “0” to the display device 7 via the display control unit 6. Specific processing contents of the three-dimensional image generation unit 5 will be described later.

  Volume rendering determines a predetermined line-of-sight direction (projection direction of projected light) for voxel data, performs ray-tracing processing from an arbitrary viewpoint, and integrates voxel values (luminance values, etc.) on the line-of-sight. By outputting the weighted cumulative addition value to the image pixels on the projection plane, the organs and the like are three-dimensionally extracted to generate a three-dimensional image.

  An image by volume rendering is generated based on pixels projected on a projection plane perpendicular to the projection ray by passing voxel data through a projection ray having a specific direction based on a specific viewpoint. An integrated value or a weighted cumulative added value is calculated from each voxel value penetrated by the projected light, and the obtained integrated value or weighted added value is stored in the pixel. Finally, a three-dimensional image is generated by collecting a plurality of pixels storing voxel values.

  The display control unit 6 receives the tomographic image data or the three-dimensional image data from the DSC 4 or the three-dimensional image generation unit 5 and causes the display device 7 to display the tomographic image or the three-dimensional image. The display device 7 can also display a tomographic image and a three-dimensional image at the same time. Further, it receives ROI marker data output from the ROI setting unit 8 to be described later, synthesizes the ROI marker data with the tomographic image data and outputs it to the display device 7, and the tomographic image and the interest on the monitor screen of the display device 7. An ROI marker representing the area is superimposed and displayed.

  The display device 7 includes a monitor such as a CRT or a liquid crystal display, and a tomographic image, a three-dimensional image, blood flow information, or the like is displayed on the monitor screen.

  The ROI setting unit 8 includes an ROI marker generation unit 81, a position information generation unit 82, and an ROI marker storage unit 83. The ROI marker generation unit 81 generates an ROI marker displayed on the monitor screen of the display device 7. The ROI marker storage unit 83 stores initial ROI marker data having a predetermined shape and a predetermined size. When receiving a region of interest (ROI) setting instruction from the operation unit 9, the initial ROI marker data stored in the ROI marker storage unit 83 is read, and the DSC 4, the three-dimensional image generation unit 5, and the display control unit 6 are read. Output to. The initially set ROI marker data is displayed at a predetermined position on the monitor screen of the display device 7. Further, the ROI marker generation unit 81 changes the shape and size of the read initial setting ROI marker in accordance with an instruction from the operation unit 9.

  The position information generation unit 82 displays the ROI marker on the monitor screen of the display device 7 when an instruction to change the position or direction of the ROI marker on the monitor screen of the display device 7 is given by the pointing device of the operation unit 9 or the like. Find the coordinates to be displayed. The coordinate data is attached to the ROI marker data generated by the ROI marker generation unit 81 and output to the DSC 4, the three-dimensional image generation unit 5 and the display control unit 6. On the monitor screen of the display device 7, the coordinate data is output. The ROI marker is displayed.

  The ROI marker storage unit 83 includes a memory such as a ROM or a hard disk, and stores initial setting ROI marker data.

  The operation unit 9 includes a pointing device such as a joystick and a trackball, switches, various buttons, a keyboard, a TCS (Touch Command Screen), and the like, and various settings relating to ultrasonic transmission / reception conditions are input by the operator. Information input through the operation unit 9 is sent to a control unit (not shown), and the control unit controls each unit of the ultrasonic diagnostic apparatus according to the information.

  For example, when displaying an ROI marker representing a region of interest (ROI) on the monitor screen of the display device 7, the operator operates a pointing device or the like while observing the monitor screen of the display device 7. The position and orientation of the ROI marker displayed above can be changed.

  The ultrasound diagnostic apparatus is provided with a control unit (not shown) and a storage unit (not shown). The control unit is composed of a CPU, is connected to each processing unit of the ultrasonic diagnostic apparatus, and executes an ultrasonic diagnostic apparatus control program, an ultrasonic image generation program, and the like stored in a memory such as a ROM. Control each processing unit. The storage unit includes a memory such as a ROM, a hard disk, and the like, and stores each data generated by the signal processing unit 3, DSC 4, or 3D image generation unit 5. Further, the storage unit stores various setting conditions of the ultrasonic diagnostic apparatus, a control program for the ultrasonic diagnostic apparatus, an ultrasonic image generation program, and the like.

(Operation)
Next, the operation (ultrasonic image generation method) of the ultrasonic diagnostic apparatus according to the embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a flowchart showing in sequence the operation of the ultrasonic diagnostic apparatus 1 according to the embodiment of the present invention. In this embodiment, a case where fetal images are collected will be described.

  The ultrasonic probe 1 transmits ultrasonic waves to the subject (maternal body in this example), receives the reflected wave from the subject (maternal), and the tomographic image data of the mother and fetus as two-dimensional information by the DSC 4 Is generated (step S01). Specifically, when a one-dimensional ultrasonic probe is used as the ultrasonic probe 1, a reflected wave from the subject (maternal body) is received as an echo signal of two-dimensional data. The echo signal input to the transmission / reception unit 2 is amplified for each reception channel by the reception unit of the transmission / reception unit 2 and then given a delay time necessary to determine reception directivity, and further added to the RF data. Is generated. The RF data input to the signal processing unit 3 is processed by a B-mode processing circuit to generate two-dimensional B-mode ultrasonic raster data. The two-dimensional B-mode ultrasound raster data is subjected to scan conversion processing by the DSC 4 and converted into tomographic image data (B-mode image data) as two-dimensional information represented by an orthogonal coordinate system.

  The tomographic image data as the two-dimensional information generated in this way is output to the display device 7 via the display control unit 6, and the maternal and fetal tomographic images are displayed on the monitor screen of the display device 7. The tomographic image data generated by the DSC 4 is stored in a storage unit (not shown).

  In this embodiment, the position of the two-dimensional scan plane is moved little by little by mechanically oscillating the ultrasonic transducer of the ultrasonic probe 1 while the above scan is repeated. And collect a plurality of tomographic image data in the swing direction.

  An example of a tomographic image displayed on the monitor screen of the display device 7 is shown in FIG. FIG. 3 is a diagram showing tomographic images collected by the ultrasonic diagnostic apparatus according to the embodiment of the present invention, and is a diagram for explaining a setting range of a region of interest (ROI) for a three-dimensional image.

  As shown in FIG. 3, a tomographic image 20 as two-dimensional information is displayed on the monitor screen of the display device 7. This tomographic image 20 is represented by an XY orthogonal coordinate system. The tomographic image 20 includes a tomographic image 21 showing the fetus. Further, in this tomographic image 20, an amniotic tomographic image 22 is displayed around a fetal tomographic image 21. As described above, since the amniotic membrane exists around the fetus in the mother body, when the whole image of the fetus is collected, the amniotic membrane around the fetus is also displayed as an image. When a three-dimensional image is reconstructed and displayed from a plurality of tomographic image data in such a state, the image of the amniotic membrane becomes a shielding object, and the fetus to be originally observed cannot be displayed and observed.

  Therefore, the region of interest (ROI) is set so that only the fetal image is displayed in the three-dimensional image. In order to set the region of interest (ROI), the operator operates the operation unit 9 to give a command for setting the region of interest (ROI) to the ultrasonic diagnostic apparatus. Operation information is output from the operation unit 9 to the ROI setting unit 8. When the ROI marker generation unit 81 of the ROI setting unit 8 receives the region of interest (ROI) setting command, it reads the initial ROI marker data stored in the ROI marker storage unit 83 and stores the ROI marker data in the DSC 4. The data is output to the three-dimensional image generation unit 5 and the display control unit 6.

  Upon receiving the ROI marker data, the display control unit 6 combines it with the tomographic image data and outputs it to the display device 7, and displays the ROI marker superimposed on the tomographic image on the monitor screen of the display device 7 (step S02). . For example, as shown in FIG. 3, the ROI marker 23 is superimposed on the tomographic image 20 and displayed. This ROI marker 23 represents an area from which an image of a part to be observed is extracted. The default ROI marker 23 has a rectangular shape, but may be changed to an arbitrary shape by the operator.

  Then, the operator operates the operation unit 9 so that the tomographic image 21 of the fetus is included in the ROI marker 23 while observing the tomographic image 21 of the fetus displayed on the monitor screen of the display device 7. Thus, the ROI marker 23 is moved or rotated (step S03).

  When the operator operates the pointing device of the operation unit 9 or the like, the ROI marker 23 is moved vertically or horizontally on the monitor screen, or is moved in the direction of arrow B as shown in FIG. The ROI marker 23 is rotated in the direction of arrow C so that the tomographic image 21 of the fetus is included in the ROI marker 23, and the ROI marker 23 is set along the direction of the fetus.

  The operator operates the pointing device or the like of the operation unit 9 while observing the fetal tomographic image 21 and the ROI marker 23 displayed on the monitor screen of the display device 7, so that the fetal tomography is in the ROI marker 23. An image 21 is included, and the position and direction of the ROI marker 23 are changed so as to follow the direction of the fetus. The operation information input by the operation unit 9 is output to the position information generation unit 82 of the ROI setting unit 8. The position information generation unit 82 calculates the coordinates of the position at which the ROI marker 23 is displayed on the monitor screen of the display device 7 according to the operation information from the operation unit 9. The position information generation unit 82 calculates coordinates expressed in the XY orthogonal coordinate system. Then, the coordinate data obtained by the position information generation unit 82 is attached to the ROI marker data and output to the display control unit 6. Note that the ROI marker data to which the coordinate data is attached is also output to the DSC 4 and the three-dimensional image generation unit 5. On the monitor screen of the display device 7, the ROI marker 23 is displayed at a position corresponding to the coordinates. By the above operation and processing, the ROI marker 23 is moved and rotated on the monitor screen of the display device 7.

  For example, as shown in FIG. 3, the ROI marker 23 is set along the direction of the fetus so that the tomographic image 21 of the fetus is included and no extra image other than the fetal image 21 is included. In this example, the tomographic image 21 of the fetus is directed obliquely with respect to the XY orthogonal coordinate axes, and the ROI marker 23 is set to the XY so that the region of interest is set along the image of the fetus directed obliquely. Set oblique to the Cartesian coordinate axis.

  The ROI marker data to which the coordinate data is attached is also output to the DSC 4 and the three-dimensional image generation unit 5. The image generation range calculation unit 41 of the DSC 4 receives the ROI marker data output from the ROI setting unit 8, circumscribes the region of interest (ROI) indicated by the ROI marker, and is a rectangle parallel to the XY orthogonal coordinate axes of the tomographic image. A shape range is obtained (step S04). The rectangular range obtained by the image generation range calculation unit 41 is the image generation range, and the voxel data generation unit 42 sets the data within the rectangular range indicated by the image generation range for all the tomographic image data. Then, the resampling process is performed to reconstruct the voxel data (step S05).

  Here, the process in which the image generation range calculation unit 41 obtains the image generation range in step S04 will be described with reference to FIG. FIG. 4 is a diagram for explaining processing for obtaining an image generation range for generating a three-dimensional image from a set region of interest (ROI).

  The image generation range calculation unit 41 circumscribes the ROI marker 23 and obtains a rectangular image generation range 25 parallel to the XY orthogonal coordinate axes of the tomographic image. Specifically, the image generation range calculation unit 41 obtains a rectangular range in which each side is in contact with each vertex 24 of the ROI marker 23, and this range becomes the image generation range 25. In this embodiment, the four vertices 24 of the ROI marker 23 are in contact with the sides of the rectangular image generation range 25. This image generation range 25 is a range for generating voxel data. The data of the image generation range 25 may be output to the display device 7 via the display control unit 6 and a marker indicating the image generation range 25 may be displayed on the monitor screen of the display device 7.

  Then, the voxel data generation unit 42 performs re-sampling processing on all of the plurality of tomographic image data in the swing direction using data within the image generation range 25 of the tomographic image data to reconstruct the voxel data ( Step S05). Since the plurality of tomographic image data are on different coordinate systems, the voxel data generation unit 42 generates voxel data by interpolating voxel values on a common coordinate system from pixel values of nearby tomographic image data. To do. At this time, voxel data is generated using data within the image generation range 25 among the tomographic image data.

  Note that if the voxel data is generated directly from the region of interest set obliquely with respect to the XY orthogonal coordinate axes, the resampling process becomes complicated, so the time required to generate the voxel data becomes long. There is a risk that the real-time property of the ultrasonic diagnostic apparatus may be hindered. Therefore, in the ultrasonic diagnostic apparatus according to this embodiment, even when the region of interest is set obliquely with respect to the XY orthogonal coordinate axis, the image generation range 25 that is parallel to the XY orthogonal coordinate axis is once obtained, Voxel data is generated from data within the range. Thus, by generating voxel data from the data in the image generation range 25 parallel to the XY orthogonal coordinate axes, the resampling process can be simplified, and as a result, the time required for voxel data generation can be shortened. A three-dimensional image can be generated without impairing the real-time property of the ultrasonic diagnostic apparatus.

  The voxel data generated by the voxel data generation unit 42 is output to the image generation unit 51 of the three-dimensional image generation unit 5. The image generation unit 51 performs volume rendering processing on the voxel data to generate three-dimensional image data, and outputs it to the image extraction unit 52 (step S06).

  The image extraction unit 52 receives the three-dimensional image data generated by the image generation unit 51, and further receives the ROI marker data output from the ROI setting unit 8, and includes a region of interest (ROI) in the three-dimensional image data. An image in a range other than is removed (step S07). For example, the image extraction unit 52 sets the pixel value of coordinates in a range other than the region of interest (ROI) to “0”. That is, in order to display only the image included in the region of interest (ROI) and not display the image other than the region of interest (ROI), the pixel values of the coordinates in the range other than the region of interest (ROI) are set to “0”. " In the image generation range 25 shown in FIG. 4, in order to display only the image included in the range indicated by the ROI marker 23, the value of the image data in the hatched area is set to “0”.

  Then, the three-dimensional image data in the region of interest (ROI) is output from the image extraction unit 52 to the display device 7 via the display control unit 6, and the three-dimensional region of interest (ROI) is displayed on the monitor screen of the display device 7. An image is displayed. In this embodiment, a three-dimensional image of the fetus is displayed. In addition, since the region of interest (ROI) is set along the fetus so as not to include a region other than the fetus, a three-dimensional image of the region of interest (the fetus in this example) can be displayed.

  Conventionally, in addition to the fetal image as the region of interest, the amniotic membrane image is not displayed, and the amniotic membrane image has been removed in order to observe the fetal image. According to this, since it is not necessary to set a cutting plane in order to remove the amniotic membrane image, complicated operations can be omitted. In addition, the skilled person is required to set the cutting plane. However, according to the ultrasonic diagnostic apparatus according to this embodiment, it is possible to easily extract and display an image of a region of interest.

  Furthermore, when the region of interest is set obliquely with respect to the XY orthogonal coordinate axes representing the tomographic image, if voxel data is generated directly from the data included in the oblique region of interest, the resampling process becomes complicated. The time required for voxel data generation is increased by the amount of the calculation, and the real-time property of the ultrasonic diagnostic apparatus may be hindered. As in this embodiment, by generating voxel data from data included in a range parallel to the XY orthogonal coordinate axes, the resampling process from tomographic image data to voxel data does not become complicated. The required time is not lengthened, and the real-time property of the ultrasonic diagnostic apparatus is not hindered. That is, according to this embodiment, since the calculation amount for generating the voxel data is small, the data creation time is shortened, and the three-dimensional image data can be generated in a time that does not hinder the real-time property. For example, even when a plurality of three-dimensional image data is generated every predetermined time and displayed as a so-called moving image, since the real-time property is not hindered, the operator can recognize it as a moving image.

  In this embodiment, a rectangular ROI marker 23 is displayed on the tomographic image 20 and a rectangular region of interest (ROI) is set. The shape of the region of interest (ROI) can be arbitrarily set by the operator. Can be changed. For example, as shown in FIG. 5, the ROI marker 26 may have a curved shape. Also in this case, the image generation range calculation unit 41 circumscribes the curved ROI marker 26 and obtains a rectangular image generation range 28 parallel to the XY orthogonal coordinate axes of the tomographic image. In the example shown in FIG. 5, the ROI marker 26 and the image generation range 28 are in contact with each other at the contact point 27. In this way, the image generation range 28 circumscribing the ROI marker 26 is obtained. Then, for all of the plurality of tomographic image data, voxel data is generated from the data in the image generation range 28 of the tomographic image data, and volume rendering processing is further performed to generate three-dimensional image data. Then, by setting the image data in a range other than the region of interest (ROI) out of the three-dimensional image data to “0”, a three-dimensional image included in the region of interest (ROI) is extracted, and the display device 7 Display on the monitor screen.

1 is a block diagram showing a schematic configuration of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. It is a flowchart which shows operation | movement of the ultrasound diagnosing device which concerns on embodiment of this invention in order. It is a figure which shows the tomogram collected by the ultrasound diagnosing device which concerns on embodiment of this invention, and is a figure for demonstrating the setting range of the region of interest (ROI) for three-dimensional images. It is a figure for demonstrating the process which calculates | requires the image generation range which produces | generates a three-dimensional image from the range of the set region of interest (ROI). It is a figure for demonstrating the process which calculates | requires the image generation range which produces | generates a three-dimensional image from the range of the set region of interest (ROI). It is a figure which shows the tomogram acquired by the ultrasound diagnosing device, and is a figure for demonstrating the range of the region of interest (ROI) set in the past.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic probe 2 Transmission / reception part 3 Signal processing part 4 DSC (digital scan converter)
DESCRIPTION OF SYMBOLS 5 3D image generation part 6 Display control part 7 Display apparatus 8 ROI setting part 9 Operation part 41 Image generation range calculation part 42 Voxel data generation part 51 Image generation part 52 Image extraction part 81 ROI marker generation part 82 Position information generation part 83 ROI marker storage

Claims (6)

Scanning means for collecting a plurality of tomographic image data in the swing direction by transmitting and receiving ultrasonic waves while swinging the ultrasonic transducer in a direction perpendicular to the scan plane;
A region of interest setting means for setting a region of interest for the tomographic image data;
Image generation range calculation means for obtaining an image generation range circumscribing the region of interest and parallel to the coordinate axis of the tomographic image data;
Volume data generating means for generating three-dimensional volume data by stacking data included in the image generation range of the tomographic image data in the swing direction for all of the plurality of tomographic image data collected in the swing direction;
3D image generation means for generating 3D image data based on the 3D volume data and extracting 3D image data included in the region of interest from the 3D image data;
Display means for displaying the extracted three-dimensional image;
An ultrasonic diagnostic apparatus comprising: The coordinate axes are orthogonal coordinate axes;
The set region of interest has a rectangular shape,
2. The ultrasonic wave according to claim 1, wherein the image generation range calculation unit obtains a rectangular image generation range in which each side is in contact with each vertex of the rectangular region of interest and is parallel to the orthogonal coordinate axis. Diagnostic device.   The three-dimensional image generation means extracts three-dimensional image data included in the region of interest by removing a three-dimensional image within the image generation range and other than the region of interest. The ultrasonic diagnostic apparatus according to claim 1 or 2.   The three-dimensional image generation means sets the pixel value of the three-dimensional image data included in the range other than the region of interest within the image generation range to “0”, thereby including the three-dimensional image included in the region of interest. The ultrasonic diagnostic apparatus according to claim 1, wherein image data is extracted. An ultrasonic diagnostic apparatus that collects a plurality of tomographic image data in the oscillation direction by transmitting and receiving ultrasonic waves while oscillating the ultrasonic transducer in a direction orthogonal to the scan plane.
A region of interest setting function for setting a region of interest for the tomographic image data;
An image generation range calculation function for obtaining an image generation range circumscribing the region of interest and parallel to the coordinate axis of the tomographic image data;
A volume data generation function for generating three-dimensional volume data by stacking data included in the image generation range of the tomographic image data in the swing direction for all of the plurality of tomographic image data collected in the swing direction;
A 3D image generation function for generating 3D image data based on the 3D volume data and extracting 3D image data included in the region of interest from the 3D image data;
A display function for displaying the extracted three-dimensional image on a display means;
An ultrasonic image generation program characterized in that An ultrasonic image that generates three-dimensional image data based on a plurality of tomographic image data collected in the oscillation direction by transmitting and receiving ultrasonic waves while oscillating the ultrasonic transducer in a direction orthogonal to the scan plane. A generation method,
A region of interest setting step in which a region of interest setting means sets a region of interest for the tomographic image data;
An image generation range calculating step for obtaining an image generation range circumscribing the region of interest and parallel to the coordinate axis of the tomographic image data;
A volume data generation unit generates three-dimensional volume data by stacking data included in the image generation range of the tomographic image data in the swing direction for all of the plurality of tomographic image data collected in the swing direction. A volume data generation step;
A 3D image generating means for generating 3D image data based on the 3D volume data, and extracting 3D image data included in the region of interest from the 3D image data;
An ultrasonic image generation method comprising:

Images