JP2008284287A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic apparatus, capable of displaying tomographic images, elastic images, and blood flow images in display modes suitable for diagnosis. <P>SOLUTION: The ultrasonic diagnostic apparatus is composed of tomographic image composing means to transmit/receive ultrasonic waves to a subject, and generate a tomographic image of a tissue of a fragment of the subject, elastic image composing means to generate an elastic image of the tissue of a fragment, and blood flow image composing means to generate a blood flow image of the subject part. A synthetic image composing means is also provided to combine the blood flow image S5 over the elastic image S6 (S7), and add the image generated at S7 over the tomographic image S4 (S8). Three kinds of images are thus synthesized in a single image to be displayed, so that an examiner is enabled to obtain three kinds of image information in one view to improve the diagnostic ability. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention uses ultrasound to generate and display a tomographic image of an imaging target site in a subject, an elastic image indicating the hardness or softness of a living tissue, and a blood flow image of the imaging target site. The present invention relates to an ultrasonic diagnostic apparatus.

  The ultrasonic diagnostic apparatus transmits ultrasonic waves to the inside of the subject using an ultrasonic probe and receives an ultrasonic reflection echo signal corresponding to the structure of the living tissue from the inside of the subject. A tomographic image such as a B-mode image is generated and displayed for diagnosis.

  In addition to ultrasonic tomographic images, for example, using the property that the ultrasonic frequency of the reflected echo signal is Doppler shifted by the movement of blood cells, the blood flow image is generated by performing Doppler demodulation, blood flow calculation, etc. on the reflected echo signal It is known to do.

  In recent years, a reflected echo signal is measured while compressing a subject with an ultrasonic probe by a manual or mechanical method, and a living body generated by compression based on frame data of two reflected echo signals having different measurement times. The displacement of each part is obtained, and an elastic image representing the elasticity of the living tissue is generated based on the displacement data.

  By the way, Patent Document 1 describes that a tomographic image and an elastic image are measured simultaneously or alternately and displayed on the same screen of an image display device. Patent Document 2 describes that an elastic image or a blood flow image is superimposed on or inserted into a tomographic image. According to this, it is said that an elastic image and a blood flow image can be observed from another viewpoint while observing the entire affected area of the subject with a tomographic image.

JP 2000-060853 A JP 2006-340745 A

  However, the techniques described in Patent Documents 1 and 2 leave more room for improving the overall diagnostic ability by displaying three types of images, a tomographic image, an elastic image, and a blood flow image.

  That is, the techniques of Patent Documents 1 and 2 display an elastic image superimposed on a tomographic image, display a blood flow image superimposed on a tomographic image, or display these superimposed images. They are displayed in parallel on the same screen. For example, in the case of parallel display, three types of images will appear on the same screen, but in this case, the examiner is accompanied by movement of the line of sight between the two images at the time of image diagnosis. It may be difficult to judge information comprehensively.

  Therefore, an object of the present invention is to realize an ultrasonic diagnostic apparatus that displays a tomographic image, an elasticity image, and a blood flow image in a display mode suitable for diagnosis.

  In order to solve the above problems, the ultrasonic diagnostic apparatus of the present invention is based on an ultrasonic probe that transmits and receives ultrasonic waves to and from a subject, and a reflected echo signal measured by the ultrasonic probe. Measured by a tomographic image construction means for generating a tomographic image of the tissue at the tomographic site of the subject, an elastic image construction means for generating an elastic image of the tissue at the tomographic site based on the reflected echo signal, and an ultrasonic probe. Blood flow image construction means for obtaining blood flow information based on the reflected echo signal and generating a blood flow image of the tomographic site; and composite image construction means for generating a composite image of the tomographic image, the elasticity image, and the blood flow image; And a display means for displaying the composite image.

  In other words, since the composite image forming means displays three types of images, ie, a tomographic image, an elastic image, and a blood flow image at the same tomographic site, in one image, the examiner can display three types of images with the same line of sight. Image information can be obtained. Therefore, the examination time can be shortened and the examination efficiency can be improved while improving the comprehensive diagnosis ability from the three types of image information.

  In this case, the following three modes can be adopted as a specific method for synthesizing the three types of images by the synthesized image constructing means.

  First, in the first aspect, a blood flow image is superimposed on the elastic image, and a superimposed image is generated by superimposing or adding the superimposed images on a tomographic image. In other words, in the synthesized image, a black and white tomographic image representing the entire tissue structure of the tomographic site is the backmost surface, and an elastic image that has been translucent and made translucent, for example, according to the tissue elasticity is intermediate The image is added as a surface, and further, an image in which a blood flow image, for example, hue gradation according to the blood flow velocity is superimposed on the foreground on the image.

  Thus, by making the elastic image translucent and adding, different information such as structural information and elastic information of the same tissue can be observed simultaneously, and the diagnostic ability can be improved. In general, since the area occupied by blood flow with respect to the entire tomographic site is small, the blood flow image is displayed in the foreground in color without being transmitted, so that the examiner can easily see.

  Next, in the second aspect, in the case where the elastic image is configured based on a correlation calculation between frame data based on a pair of reflected echo signals having different acquisition times measured by applying pressure to the subject, A blood flow image is superimposed only on a location where a correlation error has occurred in the correlation calculation on the elastic image. Then, the superimposed image is superimposed on the tomographic image or added to generate a composite image, as in the first mode.

  In this method, the blood flow image is not always displayed on the forefront, but the blood flow image is superimposed only on the part where the elastic image is not generated due to the correlation error, in other words, the blood flow image is superimposed and displayed. According to this, for example, while observing a composite image of a tomographic image and an elastic image as a main, when an elastic image is constructed, image information is lost due to a correlation error due to noise or a calculation error. If there is a blood flow image, it can be supplementarily superimposed on the artifact part. As a result, a composite image suitable for comprehensive diagnosis based on the three-image information can be provided. Further, according to this, it is possible to determine whether the portion where the elastic image is not configured by the artifact is due to the influence of blood flow or due to other factors.

  In the third aspect, in the case where the elastic image is an image that is grayed according to the elasticity of the tissue, the third mode has a portion corresponding to the grayscale range set from the entire grayscale range on the elastic image. A blood flow image is superimposed. Then, the superimposed image is superimposed on the tomographic image or added to generate a composite image, as in the first mode.

  This is not to always display the blood flow image on the forefront, but to superimpose the blood flow image on a location corresponding to the gradation range selected by the examiner or set in advance from the elastic image. To display. According to this, a blood flow image can be displayed by narrowing down to a tissue that the examiner really wants to observe in the tomographic site, and a composite image suitable for diagnosis can be provided.

  According to the present invention, it is possible to realize an ultrasonic diagnostic apparatus that displays a tomographic image, an elasticity image, and a blood flow image in a display mode suitable for diagnosis.

  Embodiments of an ultrasonic diagnostic apparatus to which the present invention is applied will be described below. In the following description, the same functional parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a block diagram showing a basic configuration of an ultrasonic diagnostic apparatus to which the present invention is applied. As shown in FIG. 1, the ultrasound diagnostic apparatus 1 includes an ultrasound probe 12 that is used while being in contact with the subject 10, and a time interval between the subject 10 and the ultrasound probe 12. A transmitter 14 that repeatedly transmits ultrasonic waves, a receiver 16 that receives time-series reflected echo signals generated from the subject 10, a transmission / reception controller 17 that controls the transmitter 14 and the receiver 16, and a receiver 16 And a phasing addition unit 18 for phasing and adding the reflected echo received in (1).

  Further, based on the RF signal frame data from the phasing adder 18, the tomographic image constructing unit 20 constituting a tomographic image of the subject, for example, a black and white tomographic image, and the output signal of the tomographic image constructing unit 20 are displayed on the image display 26 And a black-and-white scan converter 22 for conversion to suit the display.

  Further, the RF signal frame data output from the phasing addition unit 18 is stored, the RF frame data selection unit 28 that selects at least two pieces of frame data, and the displacement measurement unit that measures the displacement of the living tissue of the subject 10. 30, an elastic information calculation unit 32 that obtains strain or elastic modulus from the displacement information measured by the displacement measurement unit 30, an error evaluation unit 33 that evaluates an elastic calculation error in the elastic information calculation unit 32, and the elasticity information An elastic image construction unit 34 that constitutes a color elastic image from the strain or elastic modulus computed by the computation unit 32, and a color scan converter 36 that converts the output signal of the elastic image construction unit 34 to match the display of the image display 26 Is provided.

  In addition, a Doppler demodulation unit 47 that performs operations such as Doppler demodulation on the RF signal frame data output from the phasing addition unit 18, and a blood flow calculation unit 48 that converts the output signal of the Doppler demodulation unit 47 into blood flow information. An image processing unit 49 that performs image processing such as smoothing processing and frame correlation on the output signal from the blood flow calculation unit 48, and the output signal from the image processing unit 49 is converted to match the display on the image display 26. A color scan converter 50 is provided.

  The image processing unit 44 includes an image control unit 44 that controls the elasticity information calculation unit 32, the error evaluation unit 33, the elasticity image configuration unit 34, the color scan converters 36 and 50, and an interface unit 42 that gives an instruction to the image control unit 44. It has been.

  Then, a composition which is a characteristic part of the present invention that generates a composite image of three images of a black and white tomographic image, a color elastic image, and a blood flow image output from the black and white scan converter 22, color scan converter 36, and color scan converter 50, respectively. An image construction unit 24 and an image display 26 for displaying a composite image are provided.

  Here, the ultrasonic diagnostic apparatus 1 will be described in detail. The ultrasonic probe 12 is formed by arranging a plurality of transducers, and has a function of transmitting and receiving ultrasonic waves to and from the subject 10 via the transducers. The transmission unit 14 has a function of generating a transmission pulse for generating an ultrasonic wave by driving the ultrasonic probe 12 and setting a convergence point of the transmitted ultrasonic wave to a certain depth. Yes. The receiving unit 16 amplifies the reflected echo signal received by the ultrasonic probe 12 with a predetermined gain to generate an RF signal, that is, a received signal. The phasing adder 18 receives the RF signal amplified by the receiver 16 and performs phase control, and forms an ultrasonic beam at one point or a plurality of convergence points to generate RF signal frame data.

  The tomographic image construction unit 20 receives the RF signal frame data from the phasing addition unit 18 and performs signal processing such as gain correction, log compression, detection, contour enhancement, and filter processing to obtain tomographic image data. . The monochrome scan converter 22 also includes an A / D converter that converts tomographic image data from the tomographic image construction unit 20 into a digital signal, a frame memory that stores a plurality of converted tomographic image data in time series, and a control. It is configured to include a controller. The black and white scan converter 22 acquires tomographic frame data in the subject stored in the frame memory as one image, and reads the acquired image frame data in synchronization with the television.

  The RF frame data selection unit 28 stores a plurality of RF signal frame data from the phasing addition unit 18, and selects one set, that is, two RF signal frame data from the stored RF signal frame data group. For example, RF signal frame data generated based on the frame rate of the image in time series from the phasing adder 18 is sequentially stored in the RF frame data selector 28, and the stored RF signal frame data (N) is first At the same time, one RF signal frame data (X) is selected from among RF signal frame data groups (N-1, N-2, N-3... NM) stored in the past in time. select. Here, N, M, and X are index numbers assigned to the RF signal frame data, and are natural numbers.

  Then, the displacement measuring unit 30 performs one-dimensional or two-dimensional correlation processing from the selected set of data, that is, the RF signal frame data (N) and the RF signal frame data (X), and corresponds to each point of the tomographic image. A one-dimensional or two-dimensional displacement distribution related to the displacement and movement vector in the living tissue, that is, the direction and magnitude of the displacement is obtained. Here, a block matching method is used to detect the movement vector. The block matching method divides an image into blocks of N × N pixels, for example, pays attention to the block in the region of interest, searches the previous frame for the block that is closest to the block of interest, and refers to this Then, predictive encoding, that is, processing for determining the sample value by the difference is performed.

  The elasticity information calculation unit 32 is a strain or elasticity of a living tissue corresponding to each point on the tomographic image from a measurement value output from the displacement measurement unit 30, for example, a movement vector, and a pressure value output from the pressure measurement unit 46. The modulus is calculated, and an elastic image signal, that is, elastic frame data is generated based on the strain and elastic modulus.

  At this time, the strain data is calculated by spatially differentiating the movement amount of the living tissue, for example, the displacement. The elastic modulus data is calculated by dividing the change in pressure by the change in strain. For example, assuming that the displacement measured by the displacement measuring unit 30 is L (X) and the pressure measured by the pressure measuring unit 46 is P (X), the strain ΔS (X) spatially differentiates L (X). Therefore, it can be calculated using the equation: ΔS (X) = ΔL (X) / ΔX. Further, the Young's modulus Ym (X) of the elastic modulus data is calculated by the equation Ym = (ΔP (X)) / ΔS (X). Since the Young's modulus Ym determines the elastic modulus of the living tissue corresponding to each point in the tomographic image, two-dimensional elastic image data can be obtained continuously. The Young's modulus is a ratio of a simple tensile stress applied to the object and a strain generated in parallel with the tension.

  The error evaluation unit 33 has a function of extracting an artifact part that has caused a correlation calculation error in, for example, an echoless part, a gas part, a blood flow part, or the like when the displacement measurement part 30 performs the correlation calculation.

  The elastic image construction unit 34 is configured to include a frame memory and an image processing unit, and secures elastic frame data output in time series from the elastic information calculation unit 32 in the frame memory. In contrast, image processing is performed.

  The color scan converter 36 has a function of adding hue information to the elastic frame data from the elastic image construction unit 34. That is, the light is converted into the three primary colors of light, that is, red (R), green (G), and blue (B) based on the elastic frame data. For example, elastic data having a large strain is converted into a red code, and simultaneously elastic data having a small strain is converted into a blue code.

  The composite image configuration unit 24, which is a feature of the present invention, includes a frame memory, an image processing unit, and an image selection unit. Here, the frame memory stores tomographic image data from the black and white scan converter 22, elastic image data from the color scan converters 36 and 50, and blood flow image data.

  In addition, the image processing unit performs synthesis processing of tomographic image data, elasticity image data, and blood flow image data secured in the frame memory. The specific composition processing content will be described later. Further, the image selection unit selects an image to be displayed on the image display 26 from the tomographic image data, elasticity image data, blood flow image data, and composite image data of the image processing unit in the frame memory.

  Hereinafter, details of the composite image constructing unit 24 that is a feature of the present invention will be described for each embodiment.

  FIG. 2 is a conceptual diagram of the image composition processing of the first embodiment. As shown in FIG. 2, first, ultrasonic transmission / reception (S1) for generating tomographic images, ultrasonic transmission / reception (S2) for generating blood flow images, and ultrasonic transmission / reception (S3) for generating elastic images are performed. Do. In parallel with these processes, a tomographic image construction process (S4), a blood flow image construction process (S5), and an elasticity image construction process (S6) are performed.

  Here, the ultrasonic transmission / reception for generating the tomographic image and the ultrasonic transmission / reception for generating the elastic image are separate processes, but they can also be a common process. That is, RF signal frame data obtained by ultrasonic transmission / reception for generating a tomographic image can also be used for generating an elastic image.

  Next, the blood flow image is superimposed on the elastic image (S7). Here, superimposing means superimposing the blood flow image on the elastic image, and the blood flow image is always preferentially displayed in color at the location where the blood flow image is generated. However, you may enable it to select the display priority of this elasticity image and a blood-flow image.

  Subsequently, the image synthesized in S7 and the tomographic image are synthesized (S8). In this case, for example, the elasticity image is added to the tomographic image as a translucent color display. That is, the luminance information and the hue information of each pixel of the composite image are obtained by adding each information of the black and white tomographic image and the color elastic image at an arbitrarily set composite ratio. Then, the image combined in S8 is displayed on the image display 26 (S9).

  Here, FIG. 3 shows only a tomographic image when each tissue such as muscle, fat, thyroid gland, tumor, carotid artery, etc. of the subject is imaged, and display of the synthesized image generated by the above-described synthesis process. (B) is shown typically. This composite image generally displays a blood flow image having a small existing area with respect to the entire tomographic site in color in the foreground so that it can be easily seen by the examiner. Further, the elasticity image is added to the tomographic image as a translucent color display so that the elasticity information and morphological information of the tissue can be observed simultaneously. According to this, for example, while observing tumor hardness information, morphological information, etc., it is possible to clearly observe the direction of blood flow on the tumor, and to improve the overall diagnostic ability from three types of image information Can be planned.

  FIG. 4 is a conceptual diagram of image composition processing of the second embodiment. Since the processing of S11 to S16 is the same as that of the first embodiment, description thereof is omitted. In the present embodiment, as shown in FIG. 4, after the elastic image construction processing, the artifact portion extraction processing of the elastic image is performed (S17). Specifically, in the correlation calculation between the set of RF signal frame data in the displacement measurement unit 30, the error evaluation unit 33 extracts a part that has a correlation error as an artifact unit. The part that causes a correlation error is, for example, a part where an appropriate correlation cannot be obtained and an elastic image cannot be created.

  Subsequently, only a portion that overlaps the artifact portion is extracted from the blood flow image (S18), and the extracted blood flow image is superimposed on the elastic image generated in S16 (S19). The superimposition process here superimposes the blood flow image extracted on the elastic image, as in the first embodiment. Then, similarly to the first embodiment, the image superimposed in S19 and the tomographic image generated in S14 are synthesized (S20), and the synthesized image is subjected to display processing (S21).

  As described above, in this embodiment, the generated blood flow image is not always displayed with priority, but the blood flow image is superimposed and displayed only in a portion where an elastic image is not generated due to a correlation error.

  FIG. 5 schematically shows a display (a) of only the tomographic image when each tissue such as fat and blood vessels of the subject is imaged, and a display (b) of the synthesized image generated by the above-described synthesis process. As described above, the elastic image calculates displacement by correlation calculation between RF signal frame data, and performs strain calculation and elastic modulus calculation through spatial differentiation. For this reason, an appropriate correlation cannot be obtained in the non-echo part, the gas part, and the blood flow part, and it is difficult to construct an elastic image. For example, the image is displayed as an artifact or excluded (rejected). Is done. Therefore, if there is a blood flow image only in this excluded portion, it is superimposed to give more information on the subject to the examiner.

Thus, if there is a blood flow image in the rejection region due to the correlation error, it is additionally superimposed. For example, while observing the composite image of the tomographic image and the elasticity image as a main, the blood flow information is also added. A comprehensive diagnosis based on image information can be made.
Further, according to this, it is possible to determine whether the portion where the elastic image is not configured by the artifact is due to the influence of blood flow or due to other factors. Furthermore, since the parameters already possessed in the elastic image generation process are used, it is possible to easily determine the display area of the elastic image and the blood flow image without performing complicated processing such as translucency.

  FIG. 6 is a conceptual diagram of image composition processing of the third embodiment. Since the processing of S31 to S36 is the same as that of the first embodiment, description thereof is omitted. In this embodiment, an elastic image gradation color bar as shown in FIG. 7, for example, is displayed on the image display 26, and the inspector can select an arbitrary gradation area from the entire gradation range. . That is, since the elasticity image is a hue gradation according to the elasticity value of the tissue as described above, the hue gradation is displayed on the image display 26 as a color bar, for example, a keyboard, a mouse, The elastic range is set by the inspector using a known user interface such as a touch panel or a trackball (S37).

  Subsequently, an elasticity image corresponding to the selected elasticity range is extracted (S38), and a blood flow image for display at a location corresponding to the extracted elasticity image is extracted (S39). Then, the extracted blood flow image is superimposed on the elastic image generated in S36 (S40). The superimposition process here superimposes the blood flow image extracted on the elastic image, as in the first embodiment. Thereafter, as in the first embodiment, the image superimposed in S40 and the tomographic image generated in S34 are synthesized (S41), and the synthesized image is subjected to display processing (S42).

  As described above, in this embodiment, the range of the blood flow information can be arbitrarily selected on the color bar and is displayed on the screen. According to this, not all blood flow images are preferentially displayed on the elastic image as in the first embodiment, but only an arbitrary range can be displayed. As a result, a blood flow image can be displayed by narrowing down to a tissue that the examiner really wants to observe in the tomographic site, and the visibility of the examiner can be improved.

  In addition, as in the present embodiment, not only the elastic value range is selected using the color bar, but also various selection methods such as inputting the numerical value range of the elastic value can be employed. Also, for example, when a hardened tissue is regarded as a lesioned part and this hardened part is to be diagnosed intensively from three types of image information, instead of selecting each time, A range of elasticity values for displaying an image may be set.

  FIG. 8 is a conceptual diagram of the image composition processing of the fourth embodiment. The processes in S51 to S56 are the same as those in the above-described embodiments in that each image is generated by transmitting and receiving ultrasonic waves. However, in each of the above-described embodiments, a tomographic image, an elasticity image, and a blood flow image are generated for the entire region of the tomographic site, whereas in this embodiment, the processing capability of the ultrasonic diagnostic apparatus and the image From the viewpoint of the relationship with the frame rate or the visibility of the examiner, a region of interest is set for the elastic image and the blood flow image.

  That is, first, the tomographic image generated by the processing of S51 and S54 is displayed on the image display 26, and the tissue structure of the subject is given to the examiner. Then, the examiner sets a region of interest (hereinafter referred to as ROI) for each of the elastic image and the blood flow image via the user interface while referring to this image (S57).

  Subsequently, an elasticity image and a blood flow image in a plurality of set ROIs are generated (S55, S56), and both images are synthesized for a region where the generated elasticity image and the blood flow image overlap (S58). For the synthesis here, any one of the superimposing processes of the elastic image and the blood flow image described in the above embodiments can be employed. Then, similarly to the first embodiment, the image superimposed in S58 and the tomographic image generated in S54 are synthesized (S59), and the synthesized image is subjected to display processing (S60).

  FIG. 9 shows only a tomographic image when each tissue such as fat, muscle, thyroid gland, tumor, carotid artery, etc. of the subject is imaged, and a synthesized image generated by the above synthesis process (b). Is shown schematically. As described above, since the elastic image and the blood flow image are displayed only within the set ROI, for example, only three parts of the image information such as a tomographic image, an elastic image, and a blood flow image are displayed on the part of interest such as a tumor. Can be displayed.

  According to this, the examiner can obtain three types of image information, that is, the different information of the structure information and elasticity information of the tissue of interest and the running state of the blood flow on this tissue with the same line of sight. While improving the diagnostic ability, the inspection time can be shortened and the inspection efficiency can be improved.

  On the other hand, as shown in FIG. 10, the elastic image and the blood flow image are respectively combined with the tomographic image at a portion where the elastic image ROI and the blood flow image ROI do not overlap. Here, when the elastic image and the tomographic image are combined, the elastic image may be added to the tomographic image as a translucent color display, or may be superimposed on the tomographic image without being translucent. For the synthesis of the blood flow image and the tomographic image, the blood flow image may be superimposed on the tomographic image.

  Here, in the present embodiment, the case where the examiner sets the ROI for the elastic image and the ROI for the blood flow image has been described. For example, the ROI for both images is made common and the tomographic image is referred to as 1 The elastic image and blood flow image for the ROI may be generated and combined and displayed by setting the ROI for each time.

  Further, for example, when an elastic image ROI is set while referring to a tomographic image, an elastic image in this ROI is generated, and a portion corresponding to a preset gradation range among all gradation ranges on the elastic image In addition, a region-of-interest setting unit may be provided so that the blood flow image ROI is automatically set. After the blood flow image is generated for the automatically set ROI, the same synthesis process as described above may be performed and displayed.

  As described above, each example of the composite image constituting unit of the ultrasonic diagnostic apparatus according to the present invention has been described. In each of the above-described examples, when displaying an elastic image and a blood flow image at the same time, You may display the color bar which shows a response | compatibility with a display color, and the color bar which shows the response | compatibility with the gradation of a blood flow velocity, and a display color. In addition, a blood flow velocity threshold value can be set in advance, and only a blood flow image that is faster or slower than the threshold value or within the set threshold value range may be displayed.

It is a block diagram which shows the basic composition of the ultrasonic diagnosing device of this invention. It is a conceptual diagram of the image composition process of 1st Example. It is a figure which shows typically the display (a) of only the tomographic image of each structure | tissue of a subject, and the display (b) of the synthesized image produced | generated by the synthesis process of 1st Example. It is a conceptual diagram of the image composition process of 2nd Example. It is a figure which shows typically the display (a) of only the tomographic image of each structure | tissue of a subject, and the display (b) of the synthesized image produced | generated by the synthesis process of 2nd Example. It is a conceptual diagram of the image composition process of 2nd Example. It is a conceptual diagram which makes an inspector select arbitrary gradation area | regions by the display of the gradation color bar of an elastic image. It is a conceptual diagram of the image composition process of 4th Example. Display of only the tomographic image of each tissue of the subject (a) and display of the composite image generated by the synthesis processing of the fourth embodiment (when the ROI for elasticity image and the ROI for blood flow image overlap) ( It is a figure which shows b) typically. Display of only the tomographic image of each tissue of the subject (a) and display of the composite image generated by the synthesis processing of the fourth embodiment (when the ROI for elasticity image and the ROI for blood flow image do not overlap) ( It is a figure which shows b) typically.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic diagnostic apparatus 10 Subject 12 Ultrasonic probe 20 Tomographic image composition part 22 Black-and-white scan converter 24 Composite image composition part 26 Image display 28 RF frame data selection part 30 Displacement measurement part 32 Elastic information calculation part 33 Error evaluation Unit 34 Elastic image construction unit 36, 50 Color scan converter 44 Image control unit 47 Doppler demodulation unit 48 Blood flow calculation unit 49 Image processing unit

Claims (7)

  An ultrasonic probe that transmits and receives ultrasonic waves to and from the subject, and a tomogram that generates a tomographic image of the tissue at the tomographic site of the subject based on the reflected echo signal measured by the ultrasonic probe Blood flow information based on the image forming means, the elastic image forming means for generating an elastic image of the tissue of the tomographic site based on the reflected echo signal, and the reflected echo signal measured by the ultrasonic probe A blood flow image forming means for generating a blood flow image of the tomographic site, a composite image forming means for generating a composite image of the tomographic image, an elastic image, and a blood flow image, and a display means for displaying the composite image And an ultrasonic diagnostic apparatus.   The composite image constructing unit superimposes the blood flow image on the elasticity image, and superimposes or adds the superimposed image on the tomographic image to generate a composite image. The ultrasonic diagnostic apparatus according to 1.   The elastic image is configured based on a correlation calculation between frame data based on a pair of reflected echo signals having different acquisition times measured by applying pressure to the subject, The ultrasonic diagnostic apparatus according to claim 2, wherein the blood flow image is superimposed on a location where a correlation error has occurred in the correlation calculation on an elastic image.   The elasticity image is an image that has been gradationized according to the elasticity of the tissue, and the composite image forming means is a portion corresponding to a gradation range set from all gradation ranges on the elasticity image. The ultrasonic diagnostic apparatus according to claim 2, wherein the blood flow image is superimposed on the ultrasonic diagnostic apparatus.   A region of interest setting means for setting each of the region of interest for the elastic image and the region of interest for the blood flow image is provided on the tomographic image displayed on the display unit, and the image synthesizing unit includes both regions of interest. In the overlapping region, a composite image of the tomographic image, the elasticity image, and the blood flow image is generated, and in each region of interest other than the overlapping region, each of the elasticity image and the blood flow image is placed on the tomographic image. The ultrasonic diagnostic apparatus according to claim 1, wherein a composite image is generated by superimposing or adding.   The elastic image is a gradation image according to the elasticity of the tissue, and a blood flow image is provided at a position corresponding to a gradation range set from all gradation ranges on the elastic image. The ultrasonic diagnostic apparatus according to claim 1, further comprising a region-of-interest setting unit that sets a region of interest.   The blood flow image is an image that is hue-graded according to blood flow velocity, and the elastic image is an image that is hue-graded according to the elasticity of the tissue and is translucent. The ultrasonic diagnostic apparatus according to any one of claims 1 to 6.

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