JP2008035971A - Ultrasonic diagnosing device and motion factor calculating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance diagnosing effect relating to an ultrasonic diagnosing device and a motion factor calculating out method. <P>SOLUTION: Difference value calculating out processing for calculating out the difference value of the pixels values between the frames of the generated ultrasonic diagnosing images is carried out, thereafter the motion factors of the pixel values between the frame of the ultrasonic diagnosing images are calculated out from the difference value of the pixel values calculated out by the difference value calculating out processing. Here, the motion factors are calculated out from ones having at least threshold value in the difference value of the pixel values calculated out by the difference value calculating out processing. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus and a motion factor calculation method, and in particular, generates a plurality of frames of ultrasonic diagnostic images of a subject in chronological order based on an echo signal obtained by performing a scan. And an ultrasonic diagnostic apparatus and a motion factor calculation method for calculating a motion factor of a pixel value in the ultrasonic diagnostic image based on a result of calculating a difference value of the pixel value between frames of the generated ultrasonic diagnostic image About.

  Ultrasonic diagnostic apparatuses can display ultrasonic diagnostic images in real time as scans are performed, and are therefore widely used particularly in medical fields such as fetal screening and cardiac screening.

  When displaying an ultrasonic diagnostic image using this ultrasonic diagnostic apparatus, first, an ultrasonic beam is transmitted to the imaging region of the subject, and a scan is performed to receive the ultrasonic echo reflected in the imaging region. To obtain an echo signal. For example, the scan is performed by a scan method such as a sector scan method, a linear scan method, a convex scan method, or a radial scan method.

  Then, based on the echo signal obtained by performing the scan, an ultrasonic diagnostic image for the imaging region is generated and displayed on the display screen. In the ultrasonic diagnostic apparatus, there are various display modes such as A mode, B mode, C mode, and CFM (Color Flow Mapping, color flow mapping) mode, and an ultrasonic diagnostic image corresponding to each mode is generated. Display on the display screen.

  In addition to this, a plurality of frames of ultrasonic diagnostic images are generated in time-series order, and a difference value of pixel values between the frames of the ultrasonic diagnostic images is calculated, thereby changing the pixel value between the frames of the ultrasonic diagnostic images. After calculating a motion factor indicating the motion factor, a motion factor image indicating the motion factor may be generated and displayed. For example, in a B-mode image of a plurality of frames generated in time series, a variation value such as a change speed at which a pixel value changes and a pulsation degree at which the pixel value pulsates is calculated as a motion factor, and the value of the motion factor A motion factor image is generated and displayed with pixel values corresponding to. Thereby, the “movement” of the B-mode image can be quantitatively grasped (see, for example, Patent Document 1 and Patent Document 2).

JP 2001-269341 A JP 2004-290407 A

  However, the pixels constituting the ultrasound diagnostic image obtained by the ultrasound diagnostic apparatus include the actual examination target region (high brightness, low brightness tumor, membrane, fat, muscle, and relatively homogeneous tissue parenchyma). In addition, there is a high-intensity portion showing the surface of the ultrasonic probe, a granular noise portion that is seen where the sound wave does not reach sufficiently, and so on. On the other hand, the extraction accuracy is deteriorated. In other words, in the motion factor image as described above, it is not easy to accurately grasp the motion factor, and it is difficult to quantitatively grasp the “movement” of the B-mode image, thereby improving the diagnostic efficiency. In some cases, it was not easy. For example, when discriminating between “scrutinization” with a small motion factor and “screening” with a large motion factor, the difference between the motion factors may not be large. In some cases, it is difficult to quantitatively grasp the diagnostic efficiency, and thus it is not easy to improve the diagnostic efficiency. Similarly, when controlling the scanning method based on this motion factor, it may be difficult to carry out scanning with the optimal scanning method, and it may not be easy to improve the diagnostic efficiency. there were.

  Accordingly, an object of the present invention is to provide an ultrasonic diagnostic apparatus and a motion factor calculation method capable of improving diagnostic efficiency.

  In order to achieve the above object, the ultrasonic diagnostic apparatus of the present invention is a scan that transmits an ultrasonic beam to a subject and obtains an echo signal by performing a scan that receives an ultrasonic echo reflected from the subject. An ultrasonic diagnostic image generation unit that generates a plurality of frames of ultrasonic diagnostic images of the subject in time series based on echo signals obtained by the scanning unit, and the ultrasonic diagnostic image generation unit After performing the difference value calculation process for calculating the difference value of the pixel value between the frames of the obtained ultrasound diagnostic image, the ultrasound diagnostic image of the ultrasonic diagnosis image is calculated based on the difference value of the pixel value calculated by the difference value calculation process. An ultrasonic diagnostic apparatus having a motion factor calculation unit for calculating a motion factor of a pixel value between frames, Emissions factor calculation unit calculates the motion factor for the threshold or more of the difference value of the calculated pixel value by the difference value calculation processing.

  In order to achieve the above object, the ultrasonic diagnostic apparatus of the present invention is a scan that transmits an ultrasonic beam to a subject and obtains an echo signal by performing a scan that receives an ultrasonic echo reflected from the subject. An ultrasonic diagnostic image generation unit that generates a plurality of frames of ultrasonic diagnostic images of the subject in time series based on echo signals obtained by the scanning unit, and the ultrasonic diagnostic image generation unit After performing the difference value calculation process for calculating the difference value of the pixel value between the frames of the obtained ultrasound diagnostic image, the ultrasound diagnostic image of the ultrasonic diagnosis image is calculated based on the difference value of the pixel value calculated by the difference value calculation process. An ultrasonic diagnostic apparatus having a motion factor calculation unit for calculating a motion factor of a pixel value between frames, The factor calculation unit performs a setting process for setting a target pixel as a processing target pixel when performing the difference value calculation process in the ultrasonic diagnostic image, and then sets the processing target pixel set by the setting process. The difference value calculation process is performed for.

  In order to achieve the above object, the motion factor calculation method of the present invention provides an echo signal obtained by performing a scan for transmitting an ultrasonic beam to a subject and receiving an ultrasonic echo reflected from the subject. And an ultrasonic diagnostic image generation step for generating a plurality of frames of ultrasonic diagnostic images for the subject in time series, and pixels between the frames of the ultrasonic diagnostic images generated in the ultrasonic diagnostic image generation step. After performing the difference value calculation process for calculating the difference value of the values, the motion factor of the pixel value between the frames of the ultrasonic diagnostic image is calculated based on the difference value of the pixel value calculated by the difference value calculation process. A motion factor calculation method comprising: a motion factor calculation step comprising: In chromatography calculation step calculates the motion factor for the threshold or more of the difference value of the calculated pixel value by the difference value calculation processing.

  In order to achieve the above object, the motion factor calculation method of the present invention provides an echo signal obtained by performing a scan for transmitting an ultrasonic beam to a subject and receiving an ultrasonic echo reflected from the subject. Based on the ultrasonic diagnostic image generation step of generating a plurality of frames of ultrasonic diagnostic images of the subject in chronological order, and between the frames of the ultrasonic diagnostic images generated by the ultrasonic diagnostic image generation step, A motion factor that calculates a motion factor of a pixel value between frames of the ultrasonic diagnostic image based on a difference value of the pixel value calculated by the difference value calculation process after performing a difference value calculation process for calculating a difference value A motion factor calculation method comprising: calculating a motion factor; In the calculator calculation step, after performing a setting process for setting a target pixel as a processing target pixel when performing the difference value calculation process in the ultrasonic diagnostic image, a processing target pixel set by the setting process The difference value calculation process is performed for.

  According to the present invention, it is possible to provide an ultrasonic diagnostic apparatus and a motion factor calculation method capable of improving diagnostic efficiency.

<Embodiment 1>
(apparatus)
An ultrasonic diagnostic apparatus 1 according to a first embodiment of the present invention will be described.

  FIG. 1 is a block diagram showing a configuration of an ultrasonic diagnostic apparatus 1 in Embodiment 1 according to the present invention.

  As shown in FIG. 1, the ultrasonic diagnostic apparatus 1 of this embodiment includes an ultrasonic probe 31, an operation console 32, and a display unit 41, and transmits an ultrasonic beam to an imaging region of a subject. Then, an ultrasonic diagnostic image for the imaging region is generated based on an echo signal obtained by performing a scan for receiving an ultrasonic echo reflected in the imaging region. Each part will be described sequentially.

  The ultrasonic probe 31 is, for example, a convex type, and a plurality of ultrasonic transducers (not shown) are evenly arranged. In the ultrasonic probe 31, the ultrasonic transducer is configured to include a piezoelectric material such as PZT (lead zirconate titanate) ceramics, and converts and transmits an electric signal into an ultrasonic wave. Ultrasound is converted into an electrical signal and output as an echo signal. Here, the ultrasonic probe 31 is used with the surface on which the ultrasonic transducer is provided in contact with the surface of the subject. The ultrasonic probe 31 transmits an ultrasonic beam into the subject so as to correspond to the drive signal from the transmission / reception unit 321 based on the control signal output from the control unit 324 in the operation console 32, and the ultrasonic beam The echo signal is obtained as raw data by performing a scan for receiving an ultrasonic echo reflected from within the subject to which is transmitted. Then, the echo signal is output to the transmission / reception unit 321.

  As illustrated in FIG. 1, the operation console 32 includes a transmission / reception unit 321, an image generation unit 322, a control unit 324, an operation unit 325, and a storage unit 326. Each part of the operation console 32 includes a data processing device, and performs various data processing.

  The transmission / reception unit 321 includes a transmission / reception circuit that causes the ultrasonic probe 31 to transmit and receive ultrasonic waves, and causes the ultrasonic probe 31 to transmit an ultrasonic beam from the ultrasonic transducer to the subject based on a control signal from the control unit 324. The echo signal is generated by causing the ultrasonic transducer to receive the ultrasonic echo reflected from the subject. For example, the transmission / reception unit 321 obtains an echo signal by scanning the subject using an electronic convex scanning method, and outputs the acquired echo signal to the image generation unit 322 as sound ray data. Specifically, the transmission / reception unit 321 switches and drives the positions of a plurality of ultrasonic transducers in the ultrasonic probe 31 so as to move and scan the ultrasonic beam with respect to the subject, thereby returning an echo signal. , And the echo signal is subjected to processing such as amplification, delay, and addition, and is output to the image generation unit 322 as sound ray data.

  The image generation unit 322 is controlled by the control unit 324 so as to correspond to the command input to the operation unit 325, and generates an image.

  In the present embodiment, the image generation unit 322 includes an ultrasonic diagnostic image generation unit 322a, a motion factor calculation unit 322b, and a motion factor image generation unit 322c, as shown in FIG.

  The ultrasonic diagnostic image generation unit 322a generates an ultrasonic diagnostic image for the imaging region of the subject based on the sound ray data output from the transmission / reception unit 321. For example, a B-mode image, a CFM image, or the like is generated as an ultrasonic diagnostic image. Then, the generated ultrasonic diagnostic image is temporarily stored in, for example, a cine memory (not shown), and then output and stored in an HDD (not shown).

  The motion factor calculation unit 322b performs a difference value calculation process for calculating a difference value of pixel values between frames of the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation unit 322b. Thereafter, the motion factor of the pixel value between the frames of the ultrasound diagnostic image is calculated based on the difference value of the pixel value calculated by the difference value calculation process. In the present embodiment, the motion factor calculation unit 322b calculates a motion factor for a pixel value difference value calculated by the difference value calculation process that is equal to or greater than a threshold value.

  The motion factor image generation unit 322c generates a motion factor image based on the motion factor calculated by the motion factor calculation unit 322b. In the present embodiment, the motion factor image generation unit 322c generates a motion factor image for a portion where the difference value of the pixel value calculated by the difference value calculation process is greater than or equal to the threshold value.

  The control unit 324 includes, for example, a computer and a memory that stores a program that causes the computer to execute predetermined data processing, and gives a control signal to each unit based on an operation signal from the operation unit 325. To control the operation.

  The operation unit 325 includes, for example, a keyboard (not shown) and a track ball (not shown). The operation unit 325 receives operation information from the operator and outputs an operation signal to the control unit 324 based on the operation information. Note that the operation unit 325 may be configured by an input device such as a touch panel, a foot switch, or a voice input device.

  The display unit 41 includes, for example, an LCD device (not shown) having a flat display screen and a DSC (Digital Scan Converter) (not shown), and displays an ultrasonic diagnostic image generated by the image generation unit 322. . Although details will be described later, in the present embodiment, the B-mode image generated as the ultrasonic diagnostic image by the ultrasonic diagnostic image generation unit 322a and the motion factor image generated by the motion factor image generation unit 322c are: The images are displayed so as to overlap each other so as to correspond to each other.

(Operation)
The operation of the ultrasonic diagnostic apparatus 1 according to the first embodiment of the present invention will be described below.

  FIG. 2 is a flowchart showing the operation of the ultrasonic diagnostic apparatus 1 according to the first embodiment of the present invention. FIG. 3 is a diagram for explaining the operation of the ultrasonic diagnostic apparatus 1 according to the first embodiment of the present invention.

  As shown in FIG. 2, first, an ultrasonic diagnostic image is generated (S11).

  Here, the ultrasonic diagnostic image generation unit 322a detects the subject based on an echo signal obtained by performing a scan that transmits an ultrasonic beam to the subject and receives an ultrasonic echo reflected from the subject. A plurality of frames of ultrasonic diagnostic images are generated. For example, a B-mode image of the tomographic plane of the subject is generated as an ultrasonic diagnostic image. Then, the generated ultrasonic diagnostic image is temporarily stored in, for example, a cine memory.

  Specifically, scanning is performed on an area including an organ that moves due to respiration in the imaging area of the subject. Then, based on the echo signal obtained by performing the scan, a B-mode image of the tomographic plane along the direction in which the ultrasonic beam is transmitted in the imaging region is generated as an ultrasonic diagnostic image. Then, a plurality of frames of the B-mode image are stored in the cine memory. In this B-mode image, a state in which the organ moves by respiration is imaged.

  FIG. 3A is a diagram showing an ultrasonic diagnostic image generated in the first embodiment according to the present invention.

  As shown in FIG. 3A, for example, a scan is performed on an imaging region where the first region A, the second region B, the third region C, and the fourth region D exist as regions that move due to breathing in the subject. Then, an ultrasonic diagnostic image T (x, y) is generated for the imaging region including the regions A, B, C, and D.

  Next, as shown in FIG. 2, the motion factor is calculated (S21).

  Here, first, the motion factor calculation unit 322b performs a difference value calculation process for calculating a difference value of pixel values between frames of the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation unit 322b.

That is, in the ultrasonic diagnostic image T (x, y) generated for the tomographic plane (x, y) of the imaging region, the luminance S _i (x, y) that is the pixel value of the latest frame F _i (x, y). ) And the luminance value S _i-1 (x, y) that is the pixel value of the frame F _i-1 (x, y) generated immediately before the latest frame F _i (x, y). _i (x, y) is calculated as shown in Equation (1) below.

V _i (x, y) = S _i (x, y) −S _i−1 (x, y) (1)

The absolute value of the difference value V _i (x, y) is a motion factor of the luminance S (x, y) that is each pixel value in the B-mode image, and represents the luminance difference. Moreover, as for the sign of the difference value V _i (x, y), positive indicates an increase in luminance and negative indicates a decrease in luminance.

  FIG. 3B shows the first region A, the second region B, the third region C, and the fourth region D in the ultrasonic diagnostic image T (x, y) generated in the first embodiment according to the present invention. It is the figure which showed the luminance value of the pixel of each corresponding part according to the time axis, a vertical axis | shaft is the luminance value S, and a horizontal axis is time t. In FIG. 3B, a is the luminance transition in the first area A, b is the luminance transition in the second area B, c is the luminance transition in the third area C, and d is the fourth area D. The luminance transition at.

  FIG. 3C corresponds to the first region A, the second region B, the third region C, and the fourth region D in the ultrasonic diagnostic image T (x, y) in the first embodiment according to the present invention. FIG. 6 is a diagram showing the difference value V (x, y) of the pixels of each part corresponding to the time axis, the vertical axis is the difference value V, and the horizontal axis is the time t. In FIG. 3C, a is the difference value transition in the first area A, b is the difference value transition in the second area B, c is the difference value transition in the third area C, and d is the first It is a difference value transition in four regions D.

As shown in FIG. 3 (b), for example, time _{t k-1} and frame _{F k-1} which is generated by, in the frame _{F k} at time _{t k} immediately thereafter, the difference value Vk of each pixel value ( x, y) is calculated as described above. That is, as shown in FIG. 3A, for example, the first area A, the second area B, the third area C, and the fourth area D in the frame F _k-1 generated at the time t _k−1 . each luminance _{SA k-1 (x, y} ), SB k-1 (x, y), SC k-1 (x, y), SD k-1 (x, y) and the frame of the subsequent time _{t k} The luminances SA _k (x, y), SB _k (x, y), SC _k (x, y), SD of the first area A, the second area B, the third area C, and the fourth area D in F _{k k} (x, y) the difference value _V k (x, y) of calculating the. Then, such calculation processing is performed in each frame, and data of a difference value that changes as shown in FIG. 3C is acquired. In other words, in each frame generated at time t _k, as shown in FIG. 3 (b), the first region A, the second region B, since the luminance of the third region C is increased at a constant rate In addition, for the first area A, the second area B, and the third area C, positive difference values are calculated. Then, in each frame generated at time t _n, as shown in FIG. 3 (b), the first region A, the second region B, since the luminance of the third region C is lower at a constant rate In addition, for the first area A, the second area B, and the third area C, negative difference values are calculated. Then, in each frame generated at time t _m, as shown in FIG. 3 (b), the first area A, to the luminance of the second area B is higher at a constant rate, a positive difference While the value is calculated, since the luminance of the third region C is decreased at a constant rate, a negative difference value is calculated.

  Then, the motion factor is calculated based on the difference value of the pixel value calculated by the difference value calculation process that is equal to or greater than the threshold value.

  Specifically, as shown in FIG. 3C, the pixel difference value Vi (x, y) between the frames calculated as described above is equal to or greater than a preset threshold value TH. The difference value Vi (x, y) is specified as a motion factor.

  Next, as shown in FIG. 2, a motion factor image is generated (S31).

  Here, the motion factor image generation unit 322c generates a motion factor image indicating the motion factor of the pixel value between frames of the ultrasonic diagnostic image.

Specifically, for pixel portions where the difference value Vi (x, y) of each pixel between the frames calculated as described above is equal to or greater than a preset threshold value TH, the difference value Vi ( The brightness and display color of each pixel of the motion factor image Hi (x, y) are defined according to the value of x, y). For example, the luminance is increased according to the absolute value of the difference value V _i (x, y), and if the sign is positive, the display color is a warm color system, and if the sign is negative, the display color is a cold color system. . On the other hand, for the pixel portion where the difference value Vi (x, y) of each pixel between the frames calculated as described above is less than a preset threshold value TH, the motion factor image Hi (x, y) The luminance and display color of the pixel are defined as colorless and transparent, for example. In this way, the motion factor image Hi (x, y) is generated.

FIG. 3D, FIG. 3E, and FIG. 3F are diagrams showing the motion factor image Hi (x, y) generated in the first embodiment according to the present invention. Here, FIG. 3 (d) is a schematic diagram of FIG motion Factor image _H k at time _{t k} of (c) (x, y) . FIG. 3 (e) is a schematic diagram of the motion factor image H _n (x, y) at time t _n in FIG. 3 (c). FIG. 3F is a schematic diagram of the motion factor image H _m (x, y) at time t _m in FIG.

At time t _k, as shown in FIG. 3 (c), the first region A, the second region B, the third region C is not lower than a threshold value for the fourth area D is equal to or less than the threshold, the time In the motion factor image H _k (x, y) at t _k , as shown in FIG. 3D, the first area A is dark red, the second area B is brighter red than the first area A, The third area C is made brighter red than the second area B, and the fourth area D is colorless and transparent.

At time t _n , as shown in FIG. 3C, the first area A, the second area B, and the third area C are equal to or greater than the threshold value, and the fourth area D is equal to or less than the threshold value. In the motion factor image H _n (x, y), as shown in FIG. 3E, the first area A is dark blue, the second area B is lighter than the first area A, and the third area A The area C is made lighter blue than the second area B, and the fourth area D is colorless and transparent.

At time t _m , as shown in FIG. 3C, the first area A and the second area B are equal to or greater than the threshold value, and the third area C and the fourth area D are equal to or less than the threshold value. In the motion factor image H _m (x, y), as shown in FIG. 3 (f), the first area A and the second area B are dark red, and the third area C and the fourth area D are colorless and transparent. To.

  Next, as shown in FIG. 2, an ultrasonic diagnostic image and a motion factor image are displayed (S41).

Here, the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation unit 322a and the motion factor image generated by the motion factor image generation unit 322c are displayed so that their pixel positions and time axis positions correspond to each other. The part 41 is displayed superimposed. That is, the latest frame F _i (x, y) generated as an ultrasound diagnostic image and the motion factor image H _i (x, y) generated so as to correspond to the latest frame F _i (x, y). ) In such a manner that the display unit 41 superimposes the pixel positions so that the pixel positions correspond to each other.

  In the present embodiment, each of the above steps is sequentially and repeatedly performed to generate a plurality of frames of ultrasonic diagnostic images and motion factor images in chronological order so as to be real time with respect to the scan execution. At the same time, the ultrasonic diagnostic image and motion factor image of each frame are sequentially displayed.

  As described above, in the present embodiment, the motion factor is calculated based on the difference value of the pixel value calculated by the difference value calculation process that is equal to or greater than the threshold value. As a result, the expected “movement” can be obtained as a motion factor based on the threshold value. Therefore, the “movement” of tumors, membranes, fats, muscles and relatively homogeneous tissue parenchyma due to breathing and heartbeat can be quantitatively analyzed. Easy to grasp. Similarly, it can be clearly understood that the probe is moved. As described above, in this embodiment, since the system can grasp the movement of the probe and the movement of the subject by monitoring the motion factor value, the motion factor is small, the scrutiny that is stopped, and the motion factor is large. It is possible to automatically determine each of the moving screenings. Therefore, automatic switching of scans indicating various modes that can be performed by a normal ultrasonic diagnostic apparatus such as B mode, color mode, and PW can be accurately performed so as to be optimal for the two applications. For example, when the motion factor is small or 0, it is “scrutinized”, so that it is possible to switch to scanning with high spatial resolution by increasing the number of color and B-mode sound rays. The obtained motion factor value can also be used to control the intensity of the color flow frame average. Specifically, the weight addition processing between the frames of the color flow is performed using the magnitude of the weight factor of the frame average corresponding to the magnitude of the motion factor. For example, by applying a strong color flow frame average only when the obtained motion factor is small, only a time phase or area that is not affected by the probe, body movement, or breathing will leave a color afterimage, An image suitable for screening with good B-mode followability can be obtained without leaving an afterimage on the B-mode image while maintaining the merit that the apparent sensitivity is improved. Therefore, this embodiment can improve diagnostic efficiency.

<Embodiment 2>
Hereinafter, Embodiment 2 according to the present invention will be described.

  In the present embodiment, the operation of the difference value calculation unit 322b is different from that in the first embodiment. Except for this point, the second embodiment is the same as the first embodiment. For this reason, description is abbreviate | omitted about the overlapping location.

  The operation of the ultrasonic diagnostic apparatus 1 according to the second embodiment of the present invention will be described.

  FIG. 4 is a diagram for explaining the operation of the ultrasonic diagnostic apparatus 1 according to the second embodiment of the present invention.

  In this embodiment, the operation proceeds in the same steps as in the first embodiment.

  Therefore, as in the first embodiment, as shown in FIG. 2, first, an ultrasound diagnostic image is generated (S11).

  Next, as shown in FIG. 2, the motion factor is calculated (S21).

  Here, the motion factor calculation unit 322b performs setting processing for setting a target pixel as a processing target pixel when the difference value calculation processing is performed on the ultrasound diagnostic image.

  In this embodiment, when performing this setting process, a process target pixel is set based on the pixel value of an ultrasonic diagnostic image. Specifically, the motion factor calculation unit 322b sets, as the processing target pixel, a pixel corresponding to a pixel value within a setting range from the maximum pixel value in the ultrasound diagnostic image.

  FIG. 4A is a diagram for describing a setting process for setting a target pixel as a processing target pixel when the difference value calculation process is performed in the second embodiment of the present invention. In FIG. 4A, the pixel of each part corresponding to the first area A, the second area B, the third area C, and the fourth area D in the generated ultrasonic diagnostic image T (x, y). The luminance value is shown according to the time axis, the vertical axis is the luminance value I, and the horizontal axis is the time t. In FIG. 4A, a is the luminance transition in the first area A, b is the luminance transition in the second area B, c is the luminance transition in the third area C, and d is the fourth area D. The luminance transition at.

  As shown in FIG. 4A, in the ultrasound diagnostic image generated in a plurality of frames, the pixel corresponding to the pixel value within the setting range D from the maximum pixel value Smax is set as the processing target pixel. For example, in the frame generated at time tmax, as shown in FIG. 4A, only the pixel corresponding to the first region A is set as the processing target pixel.

  Thereafter, the difference value calculation process is performed on the processing target pixel set by the setting process in the same manner as in the first embodiment.

  Next, as shown in FIG. 2, a motion factor image is generated (S31).

FIG. 4B, FIG. 4C, and FIG. 4D are diagrams showing motion factor images Hi (x, y) generated in the second embodiment according to the present invention. Here, FIG. 4 (b) is a schematic diagram of FIG. 4 the motion factor image Hi at time _{t i} of (a) (x, y) . FIG. 4C is a schematic diagram of the motion factor image Hn (x, y) at time t _n in FIG. FIG. 4D is a schematic diagram of the motion factor image Hm (x, y) at time t _m in FIG.

As shown in FIGS. 4B, 4C, and 4D, the motion factor images Hi (x, y) and Hn (x, y) at time t _i , time t _n , and time t _m are shown. , Hm (x, y), only the portion corresponding to the first area A is displayed in the same manner as in the first embodiment.

  Next, as shown in FIG. 2, an ultrasonic diagnostic image and a motion factor image are displayed (S41).

  Here, in the same manner as in the first embodiment, the display unit 41 displays the ultrasonic diagnostic image and the motion factor image so that the pixel positions and the time axis positions correspond to each other.

  As described above, in the present embodiment, the setting process is performed in which the target pixel is set as the processing target pixel when the difference value calculation process is performed on the ultrasound diagnostic image. Thereafter, a difference value calculation process is performed for the processing target pixel set by the setting process. Here, when performing this setting process, the pixel corresponding to the pixel value within the setting range from the maximum pixel value in the ultrasound diagnostic image is set as the processing target pixel. For this reason, in the motion factor image, only the pixels corresponding to the portion corresponding to the set range from the maximum pixel value are displayed. Therefore, according to the present embodiment, it is easy to quantitatively grasp the “movement” of an actual examination target area such as a tumor, a membrane, fat, muscle, or a relatively homogeneous tissue parenchyma. Therefore, diagnostic efficiency can be improved.

<Embodiment 3>
Hereinafter, Embodiment 3 according to the present invention will be described.

  FIG. 5 is a block diagram showing the image generation unit 322 in the third embodiment of the present invention.

  In the present embodiment, as shown in FIG. 5, the image generation unit 322 includes an area setting unit 322d. The present embodiment is the same as the second embodiment except that this point differs from the operations of the difference value calculation unit 322b and the motion factor image generation unit 322c. For this reason, description is abbreviate | omitted about the overlapping location.

  The region setting unit 322d sets a pixel region that is a target when the difference value calculation process is performed on the ultrasound diagnostic image. For example, the pixel area is set based on a command from the operator. A preset area may be set as the pixel area.

  The operation of the ultrasonic diagnostic apparatus 1 according to the third embodiment of the present invention will be described.

  FIG. 6 is a diagram for explaining the operation of the ultrasonic diagnostic apparatus 1 according to the third embodiment of the present invention.

  In the present embodiment, the operation proceeds in the same steps as in the second embodiment.

  Therefore, as in the second embodiment, as shown in FIG. 2, first, an ultrasound diagnostic image is generated (S11).

  Next, as shown in FIG. 2, the motion factor is calculated (S21).

  Here, the region setting unit 322d sets a target pixel region when performing the difference value calculation process on the ultrasonic diagnostic image.

  FIG. 6A is a diagram illustrating a state in which a pixel region that is a target when a difference value calculation process is performed on an ultrasound diagnostic image is set in the third embodiment of the present invention.

  As shown in FIG. 6A, scanning is performed on an imaging region where the first region A, the second region B, the third region C, and the fourth region D exist as regions that move by breathing in the subject. In the ultrasonic diagnostic image T (x, y) generated for the imaging region including each of the regions A, B, C, and D, the first region A is used as the pixel region R that is targeted when the difference value calculation process is performed. When the operator operates the trackball of the operation unit 325, the region setting unit 322d sets the first region A as the pixel region P.

  Then, after the motion factor calculation unit 322b sets the pixel corresponding to the pixel region set by the region setting unit 322d in the ultrasonic diagnostic image as the processing target pixel, the difference value calculation processing is performed in the same manner as in the second embodiment. carry out.

  Next, as shown in FIG. 2, a motion factor image is generated (S31).

  FIG. 6B is a diagram showing a motion factor image Hi (x, y) generated in the second embodiment of the present invention.

  In the present embodiment, since the first area A is set as a pixel area by the area setting unit 322d and the difference value calculation process is performed, the motion shown for the first area A as shown in FIG. A factor image Hi (x, y) is generated. Here, in the pixel region set by the region setting unit 322d, the weighting coefficient is changed so as to decrease as it moves away from the center CE, and the motion factor image generation unit 322c uses the difference value calculation processing to change the weighting coefficient. A motion factor image Hi (x, y) is generated by performing integration so as to correspond to each of the calculated difference values Vi (x, y).

  Next, as shown in FIG. 2, an ultrasonic diagnostic image and a motion factor image are displayed (S41).

  Here, in the same manner as in the second embodiment, the display unit 41 displays the ultrasonic diagnostic image and the motion factor image so that the pixel position and the time axis position correspond to each other.

  As described above, in the present embodiment, when performing the setting process for setting the target pixel as the processing target pixel when performing the difference value calculation process in the ultrasound diagnostic image, the target pixel The area setting unit 322d sets the area. Thereafter, a difference value calculation process is performed for the processing target pixel set by the setting process. For this reason, in the motion factor image, only the pixels corresponding to the portion corresponding to the desired pixel region are displayed. Further, in the present embodiment, the weighting coefficient is changed so as to become smaller in the pixel region set as the region of interest from the center CE to the surrounding SU, and the weighting coefficient is calculated by the difference value calculation process. The motion factor image Hi (x, y) is generated by integrating the values Vi (x, y) so as to correspond to each of the values Vi (x, y). By such a weighted average according to the distance, it is possible to detect a B-mode motion that places more importance on the inter-frame difference of the B-mode image near the region of interest. Therefore, according to the present embodiment, it is easy to quantitatively grasp the “movement” of an actual examination target area such as a tumor, a membrane, fat, muscle, or a relatively homogeneous tissue parenchyma. Therefore, diagnostic efficiency can be improved.

  In implementing the present invention, the present invention is not limited to the above-described embodiment, and various modifications can be employed.

FIG. 1 is a block diagram showing a configuration of an ultrasonic diagnostic apparatus 1 in Embodiment 1 according to the present invention. FIG. 2 is a flowchart showing the operation of the ultrasonic diagnostic apparatus 1 according to the first embodiment of the present invention. FIG. 3 is a diagram for explaining the operation of the ultrasonic diagnostic apparatus 1 according to the first embodiment of the present invention. FIG. 4 is a diagram for explaining the operation of the ultrasonic diagnostic apparatus 1 according to the second embodiment of the present invention. FIG. 5 is a block diagram showing the image generation unit 322 in the third embodiment of the present invention. FIG. 6 is a diagram for explaining the operation of the ultrasonic diagnostic apparatus 1 according to the third embodiment of the present invention.

Explanation of symbols

31 ... ultrasonic probe,
32 ... Operation console,
41 ... display section,
321... Transceiver unit,
322 ... an image generation unit,
322a ... ultrasonic diagnostic image generation unit,
322b: Motion factor calculation unit,
322c: Motion factor image generation unit,
322d ... area setting unit,
324 ... control unit,
325 ... operation unit

Claims (18)

A scan unit that transmits an ultrasonic beam to a subject and obtains an echo signal by performing a scan to receive an ultrasonic echo reflected from the subject; and
Based on the echo signal obtained by the scanning unit, an ultrasonic diagnostic image generation unit that generates a plurality of frames of ultrasonic diagnostic images of the subject in time series, and
After performing the difference value calculation process for calculating the difference value of the pixel value between the frames of the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation unit, the difference value of the pixel value calculated by the difference value calculation process A motion factor calculation unit for calculating a motion factor of a pixel value between frames of the ultrasonic diagnostic image based on
The ultrasonic diagnostic apparatus, wherein the motion factor calculation unit calculates the motion factor for a pixel value difference value calculated by the difference value calculation process that is equal to or greater than a threshold value. The motion factor calculation unit performs a setting process for setting a target pixel as a processing target pixel when performing the difference value calculation process in the ultrasonic diagnostic image, and then sets the processing target set by the setting process. The ultrasonic diagnostic apparatus according to claim 1, wherein the difference value calculation process is performed on a pixel. The ultrasonic diagnostic apparatus according to claim 2, wherein the motion factor calculation unit sets the processing target pixel based on a pixel value of the ultrasonic diagnostic image when performing the setting process. The ultrasonic diagnostic apparatus according to claim 3, wherein the motion factor calculation unit sets, as the processing target pixel, a pixel corresponding to a pixel value within a setting range from a maximum pixel value in the ultrasonic diagnostic image. A motion factor image generation unit that generates a motion factor image based on the motion factor calculated by the motion factor calculation unit;
A display unit that superimposes and displays the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation unit and the motion factor image generated by the motion factor image generation unit so that the pixels correspond to each other. The ultrasonic diagnostic apparatus according to any one of claims 1 to 5. A scan unit that transmits an ultrasonic beam to a subject and obtains an echo signal by performing a scan to receive an ultrasonic echo reflected from the subject; and
Based on the echo signal obtained by the scanning unit, an ultrasonic diagnostic image generation unit that generates a plurality of frames of ultrasonic diagnostic images of the subject in time series, and
After performing the difference value calculation process for calculating the difference value of the pixel value between the frames of the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation unit, the difference value of the pixel value calculated by the difference value calculation process A motion factor calculation unit for calculating a motion factor of a pixel value between frames of the ultrasonic diagnostic image based on
The motion factor calculation unit performs a setting process for setting a target pixel as a processing target pixel when performing the difference value calculation process in the ultrasonic diagnostic image, and then sets the processing target set by the setting process. An ultrasonic diagnostic apparatus that performs the difference value calculation process on a pixel. An area setting unit for setting a pixel area to be processed when the difference value calculation process is performed in the ultrasonic diagnostic image;
The motion factor calculation unit
The ultrasonic diagnostic apparatus according to claim 6, wherein when performing the setting process, a pixel corresponding to a pixel region set by the region setting unit in the ultrasonic diagnostic image is set as the processing target pixel. The motion factor calculation unit integrates a weighting coefficient that changes with distance from the center in the pixel region set by the region setting unit to the difference value calculated in the difference value calculation process. The ultrasonic diagnostic apparatus according to claim 7, wherein a motion factor is calculated. A motion factor image generation unit that generates a motion factor image based on the motion factor calculated by the motion factor calculation unit;
A display unit that superimposes and displays the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation unit and the motion factor image generated by the motion factor image generation unit so that the pixels correspond to each other. The ultrasonic diagnostic apparatus according to any one of claims 6 to 8. Based on an echo signal obtained by transmitting an ultrasonic beam to a subject and receiving an ultrasonic echo reflected from the subject, ultrasonic diagnostic images about the subject are arranged in chronological order. An ultrasonic diagnostic image generation step for generating a plurality of frames;
After performing the difference value calculation process for calculating the difference value of the pixel value between the frames of the ultrasonic diagnostic image generated in the ultrasonic diagnostic image generation step, the difference of the pixel value calculated by the difference value calculation process A motion factor calculating step for calculating a motion factor of a pixel value between frames of the ultrasonic diagnostic image based on a value, comprising:
In the motion factor calculation step, the motion factor is calculated for a pixel value difference value calculated by the difference value calculation process that is equal to or greater than a threshold value. In the motion factor calculation step, after performing a setting process of setting a target pixel as a processing target pixel when performing the difference value calculation process in the ultrasonic diagnostic image, a process set by the setting process The motion factor calculation method according to claim 10, wherein the difference value calculation process is performed for a target pixel. The motion factor calculation method according to claim 11, wherein when the setting process is performed in the motion factor calculation step, the processing target pixel is set based on a pixel value of the ultrasonic diagnostic image. The motion factor calculation method according to claim 12, wherein in the motion factor calculation step, a pixel corresponding to a pixel value within a setting range from a maximum pixel value in the ultrasonic diagnostic image is set as the processing target pixel. A motion factor image generating step for generating a motion factor image based on the motion factor calculated by the motion factor calculating step;
A display step of superimposing and displaying the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation step and the motion factor image generated by the motion factor image generation step so that the respective pixels correspond to each other. The motion factor calculation method according to any one of claims 10 to 13. Based on an echo signal obtained by transmitting an ultrasonic beam to a subject and receiving an ultrasonic echo reflected from the subject, a plurality of ultrasonic diagnostic images of the subject are arranged in time series. An ultrasonic diagnostic image generation step for generating a frame;
After performing the difference value calculation process for calculating the difference value of the pixel value between the frames of the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation step, the difference value of the pixel value calculated by the difference value calculation process A motion factor calculating step of calculating a motion factor of a pixel value between frames of the ultrasonic diagnostic image based on
In the motion factor calculation step, after performing a setting process of setting a target pixel as a processing target pixel when performing the difference value calculation process in the ultrasonic diagnostic image, a process set by the setting process A motion factor calculation method for performing the difference value calculation process on a target pixel. An area setting step for setting a pixel area to be targeted when performing the difference value calculation process in the ultrasonic diagnostic image;
The pixel corresponding to the pixel region set by the region setting step in the ultrasonic diagnostic image is set as the processing target pixel when the setting process is performed in the motion factor calculation step. Motion factor calculation method. In the motion factor calculation step, a weighting coefficient that changes with distance from the center to the periphery in the pixel region set in the region setting step is added to the difference value calculated in the difference value calculation process. The motion factor calculation method according to claim 16, wherein the motion factor is calculated. A motion factor image generating step for generating a motion factor image based on the motion factor calculated by the motion factor calculating step;
A display step of superimposing and displaying the ultrasonic diagnostic image generated by the ultrasonic diagnostic image generation step and the motion factor image generated by the motion factor image generation step so that the pixels correspond to each other. The motion factor calculation method according to any one of claims 15 to 17.

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