JP6596907B2 - Ultrasound diagnostic imaging equipment - Google Patents

Description

  The present invention relates to an ultrasonic diagnostic imaging apparatus.

  In the ultrasonic diagnosis, the state of the heart and fetus can be obtained as an ultrasonic image by a simple operation of applying an ultrasonic probe from the body surface, and since the safety is high, the examination can be repeated. 2. Description of the Related Art An ultrasonic diagnostic imaging apparatus that is used for performing such ultrasonic diagnosis is known. The ultrasonic image data is obtained by transmitting ultrasonic waves from the ultrasonic probe to the subject, receiving the reflected ultrasonic waves by the ultrasonic probe, and performing various processes on the received signals.

  In the MSK (musculoskeletal) region for ultrasound diagnosis, images of joints, tendons, nerve bundles, etc., which have a strong anisotropy, such as circular or U-shaped boundary components, are present. The rendering ability tends to depend on the steering angle. The rendering ability is an ability to express an original part of an object in an ultrasound image. The steer angle is an angle in the emission direction of the ultrasonic beam from a direction perpendicular to the arrangement direction from the center of the arrangement of the transducers of the ultrasonic probe.

  For this reason, a method of spatial compounding that combines ultrasonic image data obtained by transmitting and receiving ultrasonic waves in a plurality of different directions (steer angles) is known.

  In a conventional spatial compound, a simple average method is used in which the reflection intensity (luminance) of ultrasonic waves in all steer angle directions is simply averaged. For this reason, there is a problem that the luminance average value is dragged by the low luminance in the steer direction in which it is difficult to draw a portion having strong anisotropy, and as a result, the drawing ability of the composite image data is extremely lowered. A simple method for solving the problem is a method of selecting the luminance in the steer angle direction in which a portion having the strong anisotropy is most depicted. Here, as a method for determining whether or not a portion having strong anisotropy is drawn, a maximum value selection method for selecting a maximum value from luminance values from each steer angle is known.

  Also, according to the type of diagnostic test to be performed, the combination method is selected from simple average, maximum value selection, etc., and the ultrasound image data is combined (synthesized) by the selected combination method, and the ultrasonic image data of the spatial compound. There is known an ultrasonic diagnostic imaging system that forms a lens (see Patent Document 1).

Japanese Patent No. 3935433

  However, in the spatial compound using the maximum luminance value, the rendering ability of a portion having strong anisotropy has been improved, but the difference in luminance value selected between pixels becomes large and the image becomes glaring. Further, for example, when displaying a moving image, there is a possibility that the ultrasonic image of the moving image will take time. FIG. 13 is a diagram showing a composite luminance value and a time contribution degree of composite image data in a conventional spatial compound.

  Here, ultrasonic image data is generated using a linear ultrasonic probe, ultrasonic image data with a steer angle of 0 degrees is set as ultrasonic image data FC, and the steer angle is a predetermined negative angle (subject Ultrasonic image data in the left direction as viewed from the ultrasound image data FL, ultrasonic image data having a predetermined positive angle (right direction as viewed from the subject) as the ultrasonic image data FR, and ultrasonic image data FR. Consider a case where synthesized image data is generated by synthesizing sonic image data FC, FL, FR. Consider the case of displaying a movie.

  As shown in FIG. 13, the ultrasonic transmission / reception sequence is generated by sequentially circulating ultrasonic image data FC, FL, FR, and the ultrasonic transmission / reception times are set as T0, T1, T2, T3. T4, T5, and so on. Here, C is a sequence for obtaining the ultrasound image data FC, L is a sequence for obtaining the ultrasound image data FL, and R is a sequence for obtaining the ultrasound image data FR. First, the ultrasound image data FC at time T0, the ultrasound image data FL at time T1, and the ultrasound image data FR at time T2 are synthesized (this is referred to as first synthesized image data), and then at time T1. The ultrasonic image data FL, the ultrasonic image data FR at time T2, and the ultrasonic image data FC at time T3 are combined (this is referred to as second combined image data), and then combined in order. The image data is displayed as a moving image. In the case of a still image, a combination of the ultrasound image data FC at time T0, the ultrasound image data FL at time T1, and the ultrasound image data FR at time T2 is displayed.

  Let the luminance values of the pixels at the same position (position on the subject) of the ultrasonic image data FC, FL, FR be Ic, Il, Ir. In the spatial compound based on the simple average method, the synthesized luminance value, which is the luminance value of the pixel of the synthesized image data, is (Ic + Il + Ir) in each synthesized image data (first synthesized image data to fourth synthesized image data in the example of FIG. 13). ) / 3, and the time contribution in the composite image data is (T0 + T1 + T2) / 3, (T1 + T2 + T3) / 3, (T2 + T3 + T4) / 3, (3) in the first composite image data to the fourth composite image data, respectively. T3 + T4 + T5) / 3... That is, in the moving image of the composite image data, there is no time turbulence such that the composite image data is displayed in a skipped manner.

  However, in the spatial compound based on the maximum value selection method, assuming that the maximum value of the luminance value of the pixel among the ultrasonic image data FC, FL, FR is Ir, the combined luminance value is the first from the first combined image data. Ir of the four composite image data, the time contribution in the composite image data is T2, T2, T2, T5,... In the first composite image data to the fourth composite image data, respectively. That is, only the combined image data of the two types of ultrasonic image data at times T2 and T5 is displayed as a moving image, and the combined image data of the ultrasonic image data of T0, T1, T3, and T4 is not displayed. In this way, the composite image data of the flying time is displayed as a moving image. In the maximum value selection method, the effective frame rate of the spatial compound is the frame rate / the number of compounds in the worst case. In addition, since the maximum luminance value is selected for each pixel in the still image, there may be a case where the difference in luminance value between pixels becomes large and the image becomes glaring.

  An object of the present invention is to improve the ability to draw a portion having strong anisotropy and display it with high image quality in displaying ultrasonic image data of a spatial compound.

In order to solve the above-mentioned problem, the invention described in claim 1
An ultrasound diagnostic imaging apparatus that includes an ultrasound probe that transmits and receives ultrasound toward a subject, and that generates ultrasound image data from a received signal obtained by the ultrasound probe,
A transmission unit that outputs a transmission signal corresponding to a plurality of different steer angles to the ultrasonic probe;
A receiving unit for receiving a reception signal corresponding to a plurality of different steer angles from the ultrasonic probe;
An image generation unit that generates ultrasonic image data from reception signals corresponding to the plurality of different steer angles;
Based on an average value Iavg of received energy of a plurality of ultrasonic image data corresponding to the plurality of different steer angles and a maximum value Imax of received energy of the plurality of ultrasonic image data, generating composite image data, and generating the composite image An image composition unit for outputting data to the display unit;
Equipped with a,
When generating the first synthesized image data and the second synthesized image data that are temporally continuous, the image synthesizing unit generates the maximum received energy Imax of the second synthesized image data and the first synthesized image data. The absolute value of the change amount with respect to the maximum value of the received energy is calculated, and the weight coefficient of the average value Iavg and the maximum value Imax is determined according to the absolute value of the change amount .
According to a second aspect of the present invention, in the ultrasonic diagnostic imaging apparatus according to the first aspect,
The weighting coefficient calculated using the function of the absolute value of the change amount of the maximum value of the received energy is Wmax, the combined received energy is Icomp,
The image composition unit generates the composite image data based on the reception energy Icomp calculated based on the following equation.
Icomp = Wmax × Imax + (1−Wmax) × Iavg

The invention according to claim 3 is the ultrasonic diagnostic imaging apparatus according to claim 1 or 2 ,
The image synthesizing unit generates an average value Iavg of received energy of pixels at the same position on the subject and a maximum value Imax of received energy of the pixels of the plurality of ultrasonic image data corresponding to the plurality of different steer angles. Based on this, composite image data of the pixel is generated.

The invention according to claim 4 is the ultrasonic diagnostic imaging apparatus according to claim 2 ,
The function is a function in which the weighting factor Wmax decreases as the absolute value of the change amount of the maximum value of received energy increases.

The invention according to claim 5 is the ultrasonic diagnostic imaging apparatus according to claim 2 or 4 ,
The function has at least one of an upper limit value and a lower limit value of the weight coefficient Wmax.

The invention according to claim 6 is the ultrasonic diagnostic imaging apparatus according to any one of claims 2 , 4 , and 5 ,
The image composition unit shows the control characteristic of the weighting factor Wmax with respect to the maximum value Imax of the received energy and the absolute value of the change amount of the maximum value of the received energy, and the weighting factor Wmax decreases as the maximum value Imax of the received energy increases. Among the three-dimensional functions, the two-dimensional function indicating the weighting factor Wmax for the absolute value of the change amount of the maximum value of the received energy corresponding to the maximum value Imax of the received energy of the second composite image data is used. A weighting coefficient Wmax corresponding to the absolute value of the calculated change amount of the maximum value of received energy is calculated.

The invention described in claim 7
An ultrasound diagnostic imaging apparatus that includes an ultrasound probe that transmits and receives ultrasound toward a subject, and that generates ultrasound image data from a received signal obtained by the ultrasound probe,
A transmission unit that outputs a transmission signal corresponding to a plurality of different steer angles to the ultrasonic probe;
A receiving unit for receiving a reception signal corresponding to a plurality of different steer angles from the ultrasonic probe;
An image generation unit that generates ultrasonic image data from reception signals corresponding to the plurality of different steer angles;
Based on an average value Iavg of received energy of a plurality of ultrasonic image data corresponding to the plurality of different steer angles and a maximum value Imax of received energy of the plurality of ultrasonic image data, generating composite image data, and generating the composite image An image composition unit for outputting data to the display unit;
With
The image synthesizing unit, when generating the first synthesized image data and a second synthesized image data to be temporally continuous, the average value of the received energy of the second synthesized image data Iavg and first synthesized image data The absolute value of the change amount with respect to the average value of the received energy is calculated, and the weight coefficient of the average value Iavg and the maximum value Imax is determined according to the absolute value of the change amount .
The invention according to claim 8 is the ultrasonic diagnostic imaging apparatus according to claim 7,
The weighting coefficient calculated using a function of the absolute value of the amount of change in the average value of the received energy is Wmax, the combined received energy is Icomp,
The image composition unit generates the composite image data based on the reception energy Icomp calculated based on the following equation .
Icomp = Wmax × Imax + (1−Wmax) × Iavg
The invention according to claim 9 is the ultrasonic diagnostic imaging apparatus according to claim 7 or 8,
The image synthesizing unit generates an average value Iavg of received energy of pixels at the same position on the subject and a maximum value Imax of received energy of the pixels of the plurality of ultrasonic image data corresponding to the plurality of different steer angles. Based on this, composite image data of the pixel is generated.

The invention according to claim 10 is the ultrasonic diagnostic imaging apparatus according to claim 8 ,
The function is a function in which the weight coefficient Wmax decreases as the absolute value of the amount of change in the average value of received energy increases.

The invention according to claim 11 is the ultrasonic diagnostic imaging apparatus according to claim 8 or 10 ,
The function has at least one of an upper limit value and a lower limit value of the weight coefficient Wmax.

The invention according to claim 12 is the ultrasonic diagnostic imaging apparatus according to any one of claims 8, 10, and 11,
The image composition unit shows control characteristics of the weighting factor Wmax with respect to the average value Iavg of the received energy and the absolute value of the change amount of the average value of the received energy, and the weighting factor Wmax decreases as the average value Iavg of the received energy increases. Of the three-dimensional functions, the two-dimensional function indicating the weighting factor Wmax for the absolute value of the change amount of the average value of the received energy corresponding to the average value Iavg of the received energy of the second composite image data is used. A weight coefficient Wmax corresponding to the absolute value of the calculated change amount of the average value of received energy is calculated.

  ADVANTAGE OF THE INVENTION According to this invention, while displaying the ultrasonic image data of a space compound, while being able to improve the drawing capability of the site | part with strong anisotropy, it can display with high image quality.

1 is an external view of an ultrasonic diagnostic imaging apparatus according to an embodiment of the present invention. It is a block diagram which shows the function structure of an ultrasonic image diagnostic apparatus. It is a figure which shows the synthesis | combination of the ultrasonic image data of a space compound. It is a figure which shows the reception energy in the ultrasonic image data before a synthesis | combination. It is a flowchart which shows the 1st image composition process performed in an image composition part. It is a figure which shows the synthetic | combination reception energy and time contribution of synthetic | combination image data in the spatial compound of (alpha) blending. (A) is the synthetic | combination image of the supraspinatus tendon by the conventional simple average method. (B) is a composite image of the supraspinatus tendon by the α blending method with a weighting factor of 0.75. (C) is a composite image of the supraspinatus tendon by the conventional maximum value selection method. It is a flowchart which shows the 2nd image composition process performed in an image composition part. It is a function figure which shows the 1st control characteristic of the weighting coefficient with respect to the absolute value of the variation | change_quantity of the maximum value of received energy. It is a function figure which shows the 2nd control characteristic of the weighting coefficient with respect to the absolute value of the variation | change_quantity of the maximum value of received energy. It is a function figure which shows the 3rd control characteristic of the weighting coefficient with respect to the absolute value of the variation | change_quantity of the maximum value of received energy. It is a figure of the function which shows the control characteristic of the weighting coefficient with respect to the maximum value of received energy, and the absolute value of the variation | change_quantity of the maximum value of received energy. It is a figure which shows the synthetic | combination brightness | luminance value and time contribution degree of the synthetic | combination image data in the conventional space compound.

  First and second embodiments according to the present invention will be described in detail in order with reference to the accompanying drawings. The present invention is not limited to the illustrated example. In addition, in the following description, what has the same function and structure attaches | subjects the same code | symbol, and abbreviate | omits the description.

(First embodiment)
A first embodiment according to the present invention will be described with reference to FIGS. First, the overall configuration of the ultrasonic diagnostic imaging apparatus 100 of the present embodiment will be described with reference to FIG. FIG. 1 is an external view of an ultrasonic diagnostic imaging apparatus 100 according to the present embodiment.

  As shown in FIG. 1, the ultrasonic diagnostic imaging apparatus 100 includes an ultrasonic diagnostic imaging apparatus main body 1 and an ultrasonic probe 2. The ultrasonic probe 2 transmits ultrasonic waves (transmission ultrasonic waves) to a subject such as a living body (not shown) and also reflects reflected waves (reflected ultrasonic waves: echoes) reflected in the subject. Receive. The ultrasonic diagnostic imaging apparatus main body 1 is connected to the ultrasonic probe 2 via a cable 3, and transmits an electric signal drive signal to the ultrasonic probe 2, thereby providing an object to the ultrasonic probe 2. Based on a received signal that is an electrical signal generated by the ultrasonic probe 2 in response to the reflected ultrasonic wave from within the subject received by the ultrasonic probe 2. Then, the internal state in the subject is imaged as ultrasonic image data.

  The ultrasonic probe 2 includes a transducer 2a (see FIG. 2) made of a piezoelectric element. For example, a plurality of the transducers 2a are arranged in a one-dimensional array in the azimuth direction (scanning direction). . In the present embodiment, for example, the ultrasonic probe 2 including 192 transducers 2a is used. Note that the vibrators 2a may be arranged in a two-dimensional array. The number of vibrators 2a can be set arbitrarily. In this embodiment, a linear electronic scanning probe is used as the ultrasonic probe 2 to perform ultrasonic scanning by the linear scanning method. However, either the sector scanning method or the convex scanning method is used. It can also be adopted. Communication between the ultrasonic diagnostic imaging apparatus main body 1 and the ultrasonic probe 2 may be performed by wireless communication such as UWB (Ultrawideband) instead of wired communication via the cable 3.

  Next, the functional configuration of the ultrasonic diagnostic imaging apparatus 100 will be described with reference to FIG. FIG. 2 is a block diagram showing a functional configuration of the ultrasonic image diagnostic apparatus 100.

  As shown in FIG. 2, the ultrasonic diagnostic imaging apparatus body 1 includes, for example, an operation input unit 11, a transmission unit 12, a reception unit 13, an image generation unit 14, an image processing unit 15, and a DSC (Digital Scan). Converter) 16, image composition unit 17, display unit 18, and control unit 19.

  The operation input unit 11 includes, for example, various switches for inputting various parameters for displaying a command for instructing diagnosis, personal information of the subject, and ultrasonic image data on the display unit 18. , Buttons, trackball, mouse, keyboard and the like, and outputs an operation signal to the control unit 19.

  The transmission unit 12 is a circuit that generates a transmission ultrasonic wave in the ultrasonic probe 2 by supplying a drive signal that is an electrical signal to the ultrasonic probe 2 via the cable 3 under the control of the control unit 19. . The transmission unit 12 includes, for example, a clock generation circuit, a delay circuit, and a pulse generation circuit. The clock generation circuit is a circuit that generates a clock signal that determines the transmission timing and transmission frequency of the drive signal. The delay circuit sets a delay time for each individual path corresponding to each transducer 2a, delays transmission of the drive signal by the set delay time, and focuses a transmission beam constituted by transmission ultrasonic waves (transmission beam forming). ) And setting of the steer angle of the transmission beam (steering). The pulse generation circuit is a circuit for generating a pulse signal as a drive signal at a predetermined cycle. The transmitter 12 configured as described above drives, for example, a continuous part (for example, 64) of a plurality (for example, 192) of the transducers 2a arranged in the ultrasound probe 2. Then, transmit ultrasonic waves are generated. And the transmission part 12 performs a scan (scan) by shifting the vibrator 2a to be driven every time a transmission ultrasonic wave is generated in the azimuth direction. Further, the transmission unit 12 can perform ultrasonic scanning in a plurality of scanning regions having different steer angles by performing scanning while changing the steer angle of the transmission beam.

  The receiving unit 13 is a circuit that receives a reception signal that is an electrical signal from the ultrasonic probe 2 via the cable 3 under the control of the control unit 19. The receiving unit 13 includes, for example, an amplifier, an A / D conversion circuit, and a phasing addition circuit. The amplifier is a circuit for amplifying the received signal at a preset amplification factor for each individual path corresponding to each transducer 2a. The A / D conversion circuit is a circuit for analog-digital conversion (A / D conversion) of the amplified received signal. The phasing addition circuit adjusts the time phase by giving a delay time to each individual path corresponding to each transducer 2a with respect to the A / D converted received signal, and adds these (phasing addition) to generate a sound. It is a circuit for generating line data. That is, the phasing addition circuit performs reception beam forming on the reception signal for each transducer 2a to generate sound ray data.

  The image generation unit 14 performs envelope detection processing, logarithmic compression, and the like on the sound ray data from the reception unit 13 and performs luminance conversion by adjusting the dynamic range and gain, thereby obtaining a luminance value as reception energy. B (Brightness) mode image data composed of pixels having In other words, the B-mode image data represents the intensity of the received signal by luminance. Here, sound ray data obtained by applying envelope detection processing or logarithmic compression to sound ray data is called reception energy, and envelope detection processing or logarithmic compression is applied to sound ray data for reception energy. A luminance value obtained by converting the luminance of the object is also included.

  The image processing unit 15 includes an image memory unit 15a configured by a semiconductor memory such as a DRAM (Dynamic Random Access Memory). The image processing unit 15 stores the B-mode image data output from the image generation unit 14 in the image memory unit 15a in units of frames. The image data in units of frames may be referred to as ultrasonic image data or frame image data. In the present embodiment, as described above, ultrasonic image data is generated for each of a plurality of scanning regions having different steer angles and stored in the image memory unit 15a. The ultrasonic image data for each scanning area may be referred to as component image data. In the component image data for each scanning area, part or all of the scanning area overlaps. The image processing unit 15 sequentially outputs the image data (component image data) generated as described above to the DSC 16.

  The DSC 16 performs coordinate conversion on the image data received from the image processing unit 15, converts the image data into image data based on a television signal scanning method, and outputs the image data to the image composition unit 17. The image data input from the image processing unit 15 are all rectangular, but the image data having a steer angle other than 0 degrees is a parallelogram as an actual image shape. When the steer angle is not 0 degree, the DSC 16 converts the rectangular image data according to the steer angle to generate parallelogram image data.

  The image composition unit 17 includes an image memory unit 17a configured by a semiconductor memory such as a DRAM (Dynamic Random Access Memory). The image composition unit 17 stores the image data output from the DSC 16 in the image memory unit 17a, and when a plurality of pieces of image data to be combined with one composite image data of the spatial compound are stored, the plurality of image data are stored. Component image data is read from the image memory unit 17 a and synthesized, and an image signal of the synthesized image data is output to the display unit 18.

  The display unit 18 may be a display device such as an LCD (Liquid Crystal Display), a CRT (Cathode-Ray Tube) display, an organic EL (Electronic Luminescence) display, an inorganic EL display, or a plasma display. The display unit 18 displays a still image or a moving image of the ultrasonic image data on the display screen according to the image signal output from the image synthesis unit 17. In the present embodiment, a 15-inch LCD having a white or full-color LED (Light-Emitting Diode) backlight is applied as the display unit 18. In this case, for example, it may be configured to adjust the luminance of the LED by analyzing the ultrasonic image data. At this time, one screen may be divided into a plurality of areas, and the brightness of the LEDs may be adjusted for each area. Moreover, you may make it implement the brightness | luminance adjustment of LED in the whole screen. Further, any screen size applied to the display unit 18 can be applied.

  The control unit 19 includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory), reads various processing programs such as a system program stored in the ROM, and expands them in the RAM. Then, the operation of each part of the ultrasonic diagnostic imaging apparatus 100 is centrally controlled according to the developed program. The ROM is configured by a nonvolatile memory such as a semiconductor, and stores a system program corresponding to the ultrasonic diagnostic imaging apparatus 100, various processing programs executable on the system program, various data such as a gamma table, and the like. These programs are stored in the form of computer-readable program code, and the CPU sequentially executes operations according to the program code. The RAM forms a work area for temporarily storing various programs executed by the CPU and data related to these programs.

  Next, an outline of the spatial compound will be described with reference to FIG. FIG. 3 is a diagram showing the synthesis of ultrasonic image data of a spatial compound.

  As shown in FIG. 3, the ultrasound diagnostic imaging apparatus 100, for example, when imaging a region OB of the subject by spatial compounding, the ultrasound image data FC with a steer angle of 0 degrees when viewed from the subject. Then, it is assumed that the ultrasonic image data FL whose steer angle direction is the left direction and the ultrasonic image data FR whose steer angle direction is the right direction are generated and combined to generate the composite image data FS. The steer angles of the ultrasonic image data FL, FC, FR are set to, for example, −8 to −12 °, 0 °, and +8 to + 12 °. When the portion OB of the subject is circular, the left and right portions of the ultrasonic image data FC are difficult to see thinly. Similarly, in the ultrasonic image data FL, it is difficult for the upper left and lower right portions to appear thin, and in the ultrasonic image data FR, the upper right and lower left portions are difficult to appear thin. On the other hand, in the composite image data FS, the circular shape of the part OB of the subject is depicted. In the present embodiment, a synthesizing method having a high rendering ability is employed in which a portion having strong anisotropy is clearly depicted as compared with the simple average method, and the synthesizing method will be described later.

  In addition, speckle (small speckle) patterns appear in the ultrasonic image data FC, FL, and FR, respectively. A speckle pattern is an infinite number of reflectors (group reflectors) in the living body that are sufficiently small compared to the wavelength of the ultrasound, and scattered waves are generated at various locations (phases). It is a pattern of random small bright spot groups (mottled dot-like images) appearing in an ultrasonic image by interference of scattered waves (back scattered waves) returning to the touch element. As the steering angle changes, so does the speckle pattern. For this reason, when the ultrasonic image data FC, FL, FR are synthesized, the speckle pattern is reduced as a result.

  Next, the operation of the image composition unit 17 in the present embodiment will be described with reference to FIGS. FIG. 4 is a diagram showing received energy (luminance values) Ic, Il, Ir in the ultrasonic image data FC, FL, FR before synthesis. FIG. 5 is a flowchart showing a first image composition process executed by the image composition unit 17. FIG. 6 is a diagram showing a composite received energy (combined luminance value) and a time contribution degree of composite image data in an α blending spatial compound (α Blending Compound). α blending is a method of combining two image data by weighting them using a coefficient (α value).

  The transmitting unit 12 and the receiving unit 13 circulate and repeat ultrasonic transmission / reception for the ultrasonic image data FC, ultrasonic transmission / reception for the ultrasonic image data FL, and ultrasonic transmission / reception for the ultrasonic image data FR. Do. The image generation unit 14 generates image data (component image data) based on the sound ray data input from the reception unit 13. The image data is subjected to coordinate conversion by the DSC 16 via the storage of the image processing unit 15 and is output to the image composition unit 17 as ultrasonic image data FC, FL, FR. The image synthesizing unit 17 stores the image data output from the DSC 16 in the image memory unit 17a until three images are stored, and when the three ultrasonic image data FC, FL, FR are accumulated, they are read and synthesized. Then, the synthesized image data of the synthesized spatial compound is output to the display unit 18. The display unit 18 displays the synthesized image data of the spatial compound sequentially input from the image synthesis unit 17 as a still image or a moving image.

  As shown in FIG. 4, the luminance values at the pixels at the same position (same position on the subject) of the ultrasound image data FC, FL, FR coordinate-converted by the DSC 16 are represented as received energy Ic, Il, Ir, respectively. .

  As shown in FIG. 5, the image composition unit 17 performs a first image composition process as a spatial compound algorithm using α blending. First, the image composition unit 17 uses the stored ultrasonic image data FC, FL, FR as an image when the ultrasonic image data FC, FL, FR continuous over time is stored in the image memory unit 17a as a trigger. An unselected pixel corresponding to the same position is selected from the pixels that are read from the memory unit 17a and overlapped in the read ultrasonic image data FC, FL, FR (step S1). Then, the image composition unit 17 acquires the reception energy Ic, Il, Ir of the selected pixels of the ultrasonic image data FC, FL, FR in all steer directions (C, L, R) (step S2).

Then, the image composition unit 17 calculates an average value Iavg as a simple average of the received energy from the received energy Ic, Il, Ir of the selected pixel acquired in step S2 by the following equation (1) (step S3).
Iavg = (Ic + Il + Ir) / 3 (1)

Then, the image composition unit 17 obtains the maximum value Imax of received energy from the received energy Ic, Il, Ir of the selected pixel obtained in step S2 by the following equation (2) (step S4).
Imax = max (Ic, Il, Ir) (2)

Then, the image composition unit 17 uses the following equations (3) and (4) to calculate the average value Iavg and the maximum value Imax of the received energy calculated in steps S3 and S4, and a weight coefficient Wmax as a preset α value, Is used to calculate the weighted average value of the α blending of the received energy and set it as the received energy Icomp of the selected pixel of the composite image data (step S5).
Wmax = constant (where 1>Wmax> 0) (3)
Icomp = Wmax × Imax + (1−Wmax) × Iavg (4)

  Then, the image composition unit 17 determines whether or not all the overlapping pixels are selected in the ultrasonic image data FC, FL, FR in step S1 (step S6). When all the pixels are not selected (step S6; NO), the image composition unit 17 proceeds to step S1. When all the pixels have been selected (step S6; YES), the image composition unit 17 generates composite image data FS composed of pixels of the reception energy Icomp and outputs it to the display unit 18 (step S7). The image composition process is terminated.

  In this algorithm, α blending is performed using a preset weighting factor Wmax, so that the luminance value is smaller than the luminance value in the maximum value selection method. However, when the received energy Icomp corresponding to one pixel is synthesized, Since the value of the reception energy of the ultrasonic image data is included as a composite component, the difference in reception energy between adjacent pixels can be reduced, and glare can be suppressed in one frame image data.

  As shown in FIG. 6, the ultrasonic transmission / reception sequence is generated by sequentially circulating ultrasonic image data FC, FL, FR, and the ultrasonic transmission / reception times are set as T0, T1, T2, T3. T4, T5, and so on. Here, C is a sequence for obtaining the ultrasound image data FC, L is a sequence for obtaining the ultrasound image data FL, and R is a sequence for obtaining the ultrasound image data FR. First, the ultrasound image data FC at time T0, the ultrasound image data FL at time T1, and the ultrasound image data FR at time T2 are synthesized (this is referred to as first synthesized image data), and then at time T1. The ultrasonic image data FL, the ultrasonic image data FR at time T2, and the ultrasonic image data FC at time T3 are combined (this is referred to as second combined image data), and then combined in order. Image data is displayed as a moving image in order. Further, it is assumed that the maximum value of the received energy of the pixel among the ultrasonic image data FC, FL, FR at times T0 to T5 is Ir.

  In spatial compounding using α blending (weighted average compound), the composite received energy of the pixels of the composite image data is the respective composite image data (in the example of FIG. 6, the first composite image data to the fourth composite image data). WmaxIr + (1−Wmax) ((Ic + Il + Ir) / 3). The time contribution in the composite image data is WmaxT2 + (1−Wmax) (T0 + T1 + T2) / 3 (time contribution of the first composite image data) in the first composite image data to the fourth composite image data, respectively. WmaxT2 + (1-Wmax) (T1 + T2 + T3) / 3 (time contribution of second composite image data), WmaxT2 + (1-Wmax) (T2 + T3 + T4) / 3 (time contribution of third composite image data), WmaxT5 + ( 1−Wmax) (T3 + T4 + T5) / 3 (time contribution of the fourth composite image data). Note that the time contribution degree indicates how much time the image data taken contributes to the composite image data.

  As described above, in the time contribution in the composite image data, a time disturbance for weighting occurs. However, by increasing the value of the weighting factor Wmax, it approximates the rendering ability of the maximum value selection method, while reducing the time disturbance by mixing values other than the maximum value with the composite image data. In other words, since image components of values other than the maximum value are also synthesized, an image consisting only of reception energy components having no time continuity in the compound transmission / reception sequence is displayed in temporally continuous synthesized image data. Disappear.

  Before displaying the composite image data moving image, in the combined image data moving image displayed in advance, while looking at the contradictory elements of the effect of the spatial compound rendering ability and the effect of the smoothness of the image display over time The setter appropriately sets the weighting factor Wmax by setting input to the operation input unit 11. The weight coefficient Wmax is set to a value of 0.6 to 0.8, for example. In addition, in the case of still image display of composite image data, the weight coefficient Wmax is set to an appropriate value so as to suppress the glare of the composite image.

  FIG. 7A is an image (composite image) when the combined image data of the supraspinatus tendon by the conventional simple average method is displayed on the display unit 18. FIG. 7B is a composite image of the supraspinatus tendon by the α blending method with the weighting factor Wmax being 0.75. FIG. 7C is a composite image of the supraspinatus tendon by the conventional maximum value selection method.

  As shown in FIG. 7 (a), the conventional image of the supraspinatus tendon by the simple average method has a low rendering capability and the brightness of the portion that must be seen inside the enclosure line is low, so the portion that cannot be seen Exists. As shown in FIG. 7 (b), the composite image of the supraspinatus tendon by the α blending method of the present embodiment with the weighting factor Wmax being 0.75 has a better rendering ability than the ultrasonic image of the simple average method. Many parts that must be visible inside the enclosure are clearly visible. As shown in FIG. 7 (c), it can be seen that the composite image of the supraspinatus tendon by the conventional maximum value selection method is a more glaring image than that of Wmax = 0.75.

  Note that the moving image of the composite image data by the α blending method with the weighting coefficient Wmax being 0.75 improves the smoothness of the image display over time as compared with the moving image of the composite image data by the conventional maximum value selection method.

  As described above, according to the present embodiment, the ultrasonic diagnostic imaging apparatus 100 includes the transmission unit 12 that outputs transmission signals corresponding to a plurality of different steer angles to the ultrasonic probe 2, and the ultrasonic probe 2. A reception unit 13 that receives reception signals corresponding to a plurality of different steer angles, an image generation unit 14 that generates ultrasonic image data from reception signals corresponding to a plurality of different steer angles, and a plurality of different steer angles The average value Iavg of the simple average of the reception energy of the plurality of ultrasonic image data is calculated, the maximum value Imax of the reception energy of the plurality of ultrasonic image data is acquired, the calculated average value Iavg and the acquired maximum value Imax And the weighting coefficient Wmax, the received energy Icomp after synthesis is calculated by the equation (4), the synthesized image data composed of the received energy Icomp is generated, and the synthesized image data is It includes an image synthesizing unit 17 to be output to the radical 113 18.

  For this reason, in the display of ultrasonic image data of a spatial compound, the term corresponding to the maximum value Imax of the received energy of a plurality of ultrasonic image data of Equation (4) is used to enhance the rendering ability of a highly anisotropic part. Can be displayed with high image quality. In addition, in the moving image display of the ultrasonic image data of the spatial compound, the term corresponding to the maximum value Imax of the received energy in Expression (4) can enhance the ability to draw a highly anisotropic portion, and Expression (4) ), The term corresponding to the average value Iavg of the received energy can be displayed smoothly over time.

  Further, the image composition unit 17 calculates an average value Iavg of received energy of pixels at the same position on the subject of a plurality of ultrasonic image data corresponding to a plurality of different steer angles, and the maximum value of received energy of the pixels. Imax is acquired, and the received energy Icomp after the synthesis of the pixel is calculated. Therefore, it is possible to generate combined image data of a spatial compound in which positions on the subject are accurately combined.

  The weighting factor Wmax is a constant value. For this reason, in the display of the ultrasonic compound data of the spatial compound, the degree of enhancing the rendering ability of the portion having strong anisotropy can be made constant. In addition, in the moving image display of the ultrasonic image data of the spatial compound, it is possible to make constant the degree of enhancing the rendering ability of the highly anisotropic part and the degree of smoothing with time. In addition, in moving image display of ultrasonic image data of spatial compound, the setter can freely weight according to the necessity of enhancing the ability to depict highly anisotropic parts and smoothing with time. The coefficient Wmax can be set in advance.

(Second Embodiment)
A second embodiment according to the present invention will be described with reference to FIGS. In the present embodiment, the ultrasonic diagnostic imaging apparatus 100 is used as in the first embodiment. In the ultrasonic diagnostic imaging apparatus 100, only the image composition unit 17 performs an operation different from that of the first embodiment. Specifically, the method of synthesizing the ultrasonic compound data of the spatial compound in the image synthesizing unit 17 is different from that of the first embodiment. For this reason, the different operations are mainly described, and description of other elements is omitted.

  With reference to FIGS. 8 to 12, the operation of the image composition unit 17 in the present embodiment will be described. FIG. 9 is a function diagram illustrating a first control characteristic of the weighting factor Wmax with respect to the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the reception energy (luminance). FIG. 10 is a function diagram illustrating a second control characteristic of the weighting factor Wmax with respect to the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the reception energy. FIG. 11 is a function diagram illustrating a third control characteristic of the weighting factor Wmax with respect to the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the reception energy. FIG. 12 is a function diagram showing the control characteristic of the weighting factor Wmax with respect to the maximum value Imax of the received energy and the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the received energy.

  As illustrated in FIG. 8, the image composition unit 17 performs a second image composition process as a spatial compound algorithm using α blending. First, the image composition unit 17 uses the stored ultrasonic image data FC, FL, FR as an image when the ultrasonic image data FC, FL, FR continuous over time is stored in the image memory unit 17a as a trigger. An unselected pixel corresponding to the same position is selected from the pixels that are read from the memory unit 17a and overlapped in the read ultrasonic image data FC, FL, FR (step S11). Then, the image composition unit 17 acquires received energy (luminance values) Ic, Il, Ir of the selected pixels of the ultrasonic image data FC, FL, FR in all steer directions (C, L, R) (step S12). .

  Then, the image synthesizing unit 17 calculates a simple average value Iavg of the received energy from the received energy Ic, Il, Ir of the selected pixel acquired in Step S12 according to Expression (1) (Step S13). Then, the image synthesizing unit 17 obtains the maximum value Imax of received energy from the received energy Ic, Il, Ir of the selected pixel obtained in Step S12 according to Expression (2) (Step S14).

Then, the image composition unit 17 stores the maximum value Imax of received energy calculated in step S14 in the image memory unit 17a as the previous maximum value Imaxprev of received energy in order to use it in the next calculation (step S15). In step S15, for example, the previous maximum value Imaxprev of the reception energy of the selected pixel is stored in the image memory unit 17a in association with the selected pixel as composite image data including the previous maximum value Imaxprev. Then, the image composition unit 17 obtains the previous maximum value Imaxprev of the reception energy of the selected pixel stored in step S15 at the time of generating the previously generated composite image data (composite image data of the previous frame). The absolute value Abs () of the change amount of the maximum value of received energy using the current received energy maximum value Imax calculated in step S14 and the read previous maximum value Imaxprev according to the following equation (5). Imax-Imaxprev) is calculated (step S16).
Abs (Imax−Imaxprev) = | Imax−Imaxprev | (5)

Then, the image composition unit 17 calculates the weighting coefficient Wmax using the function of the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the reception energy calculated in step S16 by the following equation (6) ( Step S17).
Wmax = Func (Abs (Imax−Imaxprev)) (6)

  Then, the image composition unit 17 uses the equation (4) to calculate the reception energy α using the average value Iavg and the maximum value Imax of the reception energy calculated in steps S13 and S14 and the weighting factor Wmax calculated in step S16. A weighted average value of blending is calculated and set as reception energy Icomp of the selected pixel of the composite image data (step S18).

  Then, the image composition unit 17 determines whether or not all the overlapping pixels are selected in the ultrasonic image data FC, FL, FR in step S11 (step S19). When all the pixels are not selected (step S19; NO), the image composition unit 17 proceeds to step S11. When all the pixels have been selected (step S19; YES), the image composition unit 17 generates composite image data FS composed of pixels having the reception energy Icomp and outputs the composite image data FS to the display unit 18 (step S20). The image composition process is terminated.

  The algorithm of the present embodiment performs α blending while adaptively changing the weighting factor Wmax in the algorithm of the first embodiment. As an argument for adaptively changing the weight coefficient Wmax, an absolute value (Abs (Imax−Imaxprev)) of a change amount between the current maximum value Imax and the previous maximum value Imaxprev is used. This uses the property that the received energy (luminance) changes when the ultrasonic image changes. Also, when the ultrasonic image changes, the average value of the received energy can be used to reduce the disturbance of time, and when the ultrasonic image does not change, the maximum value of the received energy is different. It is possible to include both of the advantages of improving the ability to depict a highly anisotropic part.

  The function Func (Abs (Imax−Imaxprev)) of the equation (6) takes a larger value of the weight coefficient Wmax as the absolute value Abs (Imax−Imaxprev) of the amount of change in the maximum value of the received energy is smaller, and the maximum received energy is larger. The function is such that the weighting coefficient Wmax becomes smaller as the absolute value Abs (Imax−Imaxprev) of the value change amount is larger. This is because when the ultrasonic image moves, the difference between the maximum value Imax of the received energy and the previous maximum value Imaxprev changes. However, when the ultrasonic image moves greatly, the amount of change in the maximum value of the received energy increases. Therefore, when it does not move so much, it is used that the amount of change in the maximum value of the received energy tends to be small.

  As the function Func (Abs (Imax−Imaxprev)), for example, a linear function having a graph relationship shown in FIG. 9 is used. The image composition unit 17 may be configured to store a table reflecting the graph shown in FIG. 9 in the image memory unit 17a in advance, and to read and use the table when calculating the weighting coefficient Wmax, or as shown in FIG. The weight coefficient Wmax may be calculated using a graph equation.

  In the synthesis of image data, a function having a graph relationship shown in FIG. 10 or 11 may be used as the function Func (Abs (Imax−Imaxprev)). The graphs shown in FIGS. 10 and 11 show weights when the absolute value Abs (Imax−Imaxprev) of the amount of change in the maximum value of the received energy is within a certain range by setting the upper and lower limits of the weighting factor Wmax. The coefficient Wmax can be made constant. For example, the upper limit (0 ≦ upper limit value of the weighting factor Wmax, lower limit value ≦ 1.0) of the weighting factor Wmax shown in FIG. 10 is an effect of suppressing the glare due to the term of the maximum value Imax of the reception energy in the equation (4). Play. The upper and lower limits of the weighting factor Wmax shown in FIG. 10 have the effect of preventing the change between the received energy when the ultrasonic image is moved and the received energy when the ultrasonic image is not moved from becoming extreme. The upper limit (Wmax = 1.0) of the weighting factor Wmax shown in FIG. 11 makes it possible to depict a stable and strongly anisotropic portion even if a slight change in received energy is seen in the ultrasonic image. The function Func (Abs (Imax−Imaxprev)) may be configured to have an upper limit value or a lower limit value of the weighting coefficient Wmax.

  In the calculation policy using the graphs shown in FIG. 9, FIG. 10, and FIG. 11, the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the received energy and the weighting factor Wmax The weighting factor Wmax was calculated using a graph. The relationship between the three axes of the maximum value Imax of received energy, the absolute value Abs (Imax−Imaxprev) of the amount of change in the maximum value of received energy, and the weighting factor Wmax A graph may be used.

  The graph shown in FIG. 12 may be used as the graph of the relationship between the three axes. In the graph shown in FIG. 12, the weighting factor Wmax decreases as the maximum value Imax of received energy increases. From the graph shown in FIG. 12, the image composition unit 17 calculates the absolute value Abs (Imax−Imaxprev) of the amount of change in the maximum value of the received energy corresponding to the current maximum value Imax of the received energy and the weighting coefficient Wmax. A graph of the biaxial relationship is extracted, and the expression (6) is calculated using the extracted graph as a function Func (Abs (Imax−Imaxprev)).

  When the maximum value Imax of the reception energy is a relatively large value, even if the ratio of the average value Iavg of the reception energy is increased (the weighting factor Wmax is reduced as shown in the graph of FIG. 12), the reception of the composite image data is performed. It is possible to keep the energy Icomp at a luminance that can be identified on the ultrasonic image, and to suppress temporal disturbance of the moving image. On the contrary, when the maximum value Imax of the received energy is a relatively small value, even if the ratio of the average value Iavg of the received energy is increased, the received energy Icomp of the composite image data does not have a luminance that can be identified on the ultrasonic image. Therefore, by increasing the ratio of the maximum value Imax of the received energy (increasing the weighting factor Wmax as shown in the graph of FIG. 12), the time disturbance of the moving image increases, but the received energy Icomp of the composite image data is converted into the ultrasonic image. It becomes possible to keep the brightness distinguishable above.

  As described above, according to the present embodiment, the transmission unit 12 sequentially transmits transmission signals corresponding to a plurality of different steer angles, and the image synthesis unit 17 includes the first synthesized image data and the second temporally continuous image data. The absolute value Abs of the amount of change between the maximum value Imax of the reception energy of the second composite image data and the previous maximum value of the reception energy calculated when the first composite image data is generated when generating the composite image data of (Imax−Imaxprev) is calculated, and the function Func (Abs (Imax−Imaxprev)) indicating the control characteristic of the weighting factor Wmax with respect to the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the reception energy is used. A weighting factor Wmax corresponding to the absolute value Abs (Imax−Imaxprev) of the calculated change amount of the maximum value of the received energy is calculated. For this reason, when the ultrasonic image changes in the moving image display of the ultrasonic image data of the spatial compound, the average value Iavg of the received energy can be used to display smoothly and the ultrasonic image does not change In addition, using the maximum value Imax of the received energy, it is possible to improve the drawing ability of a portion having strong anisotropy, and both advantages can be included.

  The function Func (Abs (Imax−Imaxprev)) is a function in which the weight coefficient Wmax decreases as the absolute value Abs (Imax−Imaxprev) of the maximum amount of change in received energy increases. For this reason, when the ultrasound image moves greatly, the amount of change in the maximum value of the received energy becomes large, and it can be displayed smoothly over time using the average value Iavg of the received energy. The amount of change in the maximum value of energy is reduced, and the drawing ability of a portion having strong anisotropy can be improved.

  Further, as shown in FIGS. 10 and 11, the function Func (Abs (Imax−Imaxprev)) has at least one of an upper limit value and a lower limit value of the weighting coefficient Wmax. Therefore, in the moving image display of the ultrasonic image data of the spatial compound, glare due to the maximum value component of the received energy can be suppressed by the upper limit value of the weight coefficient Wmax, and the ultrasonic image can be suppressed by the upper limit value and the lower limit value of the weight coefficient Wmax. It is possible to prevent the change between the reception energy when moving and the reception energy when the ultrasonic image does not move from becoming extreme.

  Further, the image composition unit 17 shows the control characteristic of the weighting factor Wmax for the maximum value Imax of received energy and the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of received energy, and the maximum value Imax of received energy is Among the three-dimensional functions as shown in FIG. 12, the weight coefficient Wmax decreases as the value increases. The weight for the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the received energy corresponding to the current maximum value Imax of the received energy. Using a two-dimensional function Func (Abs (Imax−Imaxprev)) indicating the coefficient Wmax, a weighting factor Wmax corresponding to the absolute value Abs (Imax−Imaxprev) of the calculated maximum amount of received energy is calculated. Therefore, in the moving image display of the ultrasonic image data of the spatial compound, when the maximum value Imax of the received energy is a relatively large value, the received energy Icomp of the composite image data can be kept at a luminance that can be identified on the ultrasonic image. If the ratio of the maximum received energy Imax is increased when the maximum received energy value Imax is relatively small, the time turbulence of the moving image increases, but the received energy Icomp of the composite image data is increased. Can be kept at a luminance that can be identified on an ultrasonic image.

  The description in each of the above embodiments is an example of a preferable ultrasonic image diagnostic apparatus according to the present invention, and the present invention is not limited to this.

  For example, in each of the above-described embodiments, the configuration is such that the composite image data FS of the spatial compound is generated by synthesizing the three ultrasonic image data FC, FL, FR having different steer angles. However, the present invention is not limited to this. Absent. A configuration may be adopted in which two or three or more ultrasonic image data with different steer angles are combined to generate combined image data of a spatial compound. For example, when five pieces of ultrasonic image data having different steer angles are synthesized, the steer angles are set to, for example, −12 °, −8 °, 0 °, + 8 °, and + 12 °.

  In each of the above embodiments, the average value Iavg of received energy has been described as an average value of a simple average (arithmetic average), but is not limited to this. For example, the average value Iavg of received energy may be an average value of another averaging method such as a geometric average.

  In each of the above embodiments, the image composition unit 17 performs composition of image data. However, the present invention is not limited to this. Instead of the image composition unit 17, the control unit 19 performs composition of the ultrasound image data output from the DSC 16 by executing an image composition program for performing image data composition processing similar to that of the image composition unit 17. The composite image data may be displayed on the display unit 18.

In the second embodiment, the maximum reception energy value Imax and the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum reception energy are used. However, the present invention is not limited to this. is not. The maximum value Imax of the received energy is the average value Iavg of the received energy, the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the received energy is the absolute value Abs (Iavg−Iavgprev) of the change amount of the average value of the received energy, It is good also as a structure replaced like this. The absolute value Abs (Iavg−Iavgprev) of the change amount of the average value of the reception energy is received when the first composite image data and the second composite image data that are temporally continuous are generated. It is the absolute value of the amount of change between the energy average value Iavg and the previous average value of the received energy calculated when the first composite image data is generated. Expressions (5) and (6) are replaced with the following expressions (7) and (8).
Abs (Iavg−Iavgprev) = | Iavg−Iavgprev | (7)
Wmax = Func (Abs (Iavg-Iavgprev)) (8)

  According to this configuration, when the result of the absolute value Abs (Imax−Imaxprev) of the change amount of the maximum value of the reception energy may change drastically, the average value Iavg of the reception energy, the reception By using the absolute value Iavgprev of the amount of change in the average value of energy, flicker can be alleviated. Similar to the configuration using the maximum value Imax of the received energy and the absolute value Imaxprev of the change amount of the maximum value of the received energy, the average value Iavg of the received energy and the absolute value Iavgprev of the change amount of the average value of the received energy may be used. It can be detected that the ultrasonic image has moved.

  In each of the above embodiments, the image composition unit 17 synthesizes the luminance values as the reception energy of a plurality of ultrasonic image data generated by the image generation unit 14 and converted by the DSC 16. It is not limited. The image synthesizing unit receives, as received energy, ultrasonic image data at any stage from the sound ray data subjected to the envelope detection processing, logarithmic compression, and the like by the image generation unit 14 to the image data input to the display unit 18. You may synthesize. For example, the image synthesizing unit synthesizes the sound ray data that has been subjected to the envelope detection processing, logarithmic compression, and the like by the image generation unit 14 (for each pixel at the same position in the synthesized image data) and generates the synthesized sound ray data. It is good also as a structure which produces | generates and the image generation part 14 produces | generates synthetic | combination image data by carrying out brightness | luminance conversion of the said synthetic | combination sound ray data produced | generated.

  Further, the detailed configuration and detailed operation of each part constituting the ultrasonic diagnostic imaging apparatus 100 in the above embodiment can be changed as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 Ultrasonic image diagnostic apparatus 1 Ultrasonic image diagnostic apparatus main body 11 Operation input part 12 Transmission part 13 Reception part 14 Image generation part 15 Image processing part 15a Image memory part 16 DSC
17 Image composition unit 17a Image memory unit 18 Display unit 19 Control unit 2 Ultrasonic probe 2a Transducer 3 Cable

Claims (12)

An ultrasound diagnostic imaging apparatus that includes an ultrasound probe that transmits and receives ultrasound toward a subject, and that generates ultrasound image data from a received signal obtained by the ultrasound probe,
A transmission unit that outputs a transmission signal corresponding to a plurality of different steer angles to the ultrasonic probe;
A receiving unit for receiving a reception signal corresponding to a plurality of different steer angles from the ultrasonic probe;
An image generation unit that generates ultrasonic image data from reception signals corresponding to the plurality of different steer angles;
Based on an average value Iavg of received energy of a plurality of ultrasonic image data corresponding to the plurality of different steer angles and a maximum value Imax of received energy of the plurality of ultrasonic image data, generating composite image data, and generating the composite image An image composition unit for outputting data to the display unit;
Equipped with a,
When generating the first synthesized image data and the second synthesized image data that are temporally continuous, the image synthesizing unit generates the maximum received energy Imax of the second synthesized image data and the first synthesized image data. An ultrasonic diagnostic imaging apparatus that calculates an absolute value of a change amount with respect to a maximum value of received energy and determines a weighting coefficient of an average value Iavg and a maximum value Imax according to the absolute value of the change amount . The weighting coefficient calculated using the function of the absolute value of the change amount of the maximum value of the received energy is Wmax, the combined received energy is Icomp,
The ultrasonic image diagnostic apparatus according to claim 1, wherein the image composition unit generates the composite image data based on a reception energy Icomp calculated based on the following expression.
Icomp = Wmax × Imax + (1−Wmax) × Iavg The image synthesizing unit generates an average value Iavg of received energy of pixels at the same position on the subject and a maximum value Imax of received energy of the pixels of the plurality of ultrasonic image data corresponding to the plurality of different steer angles. based ultrasound imaging apparatus according to claim 1 or 2 to generate a composite image data of the pixel. The ultrasound diagnostic imaging apparatus according to claim 2 , wherein the function is a function in which the weighting coefficient Wmax decreases as the absolute value of the change amount of the maximum value of received energy increases . The ultrasound diagnostic imaging apparatus according to claim 2 , wherein the function has at least one of an upper limit value and a lower limit value of the weighting coefficient Wmax . The image composition unit shows the control characteristic of the weighting factor Wmax with respect to the maximum value Imax of the received energy and the absolute value of the change amount of the maximum value of the received energy, and the weighting factor Wmax decreases as the maximum value Imax of the received energy increases. Among the three-dimensional functions, the two-dimensional function indicating the weighting factor Wmax for the absolute value of the change amount of the maximum value of the received energy corresponding to the maximum value Imax of the received energy of the second composite image data is used. The ultrasonic diagnostic imaging apparatus according to any one of claims 2, 4, and 5, wherein a weighting factor Wmax corresponding to an absolute value of the calculated change amount of the maximum value of received energy is calculated . An ultrasound diagnostic imaging apparatus that includes an ultrasound probe that transmits and receives ultrasound toward a subject, and that generates ultrasound image data from a received signal obtained by the ultrasound probe,
A transmission unit that outputs a transmission signal corresponding to a plurality of different steer angles to the ultrasonic probe;
A receiving unit for receiving a reception signal corresponding to a plurality of different steer angles from the ultrasonic probe;
An image generation unit that generates ultrasonic image data from reception signals corresponding to the plurality of different steer angles;
Based on an average value Iavg of received energy of a plurality of ultrasonic image data corresponding to the plurality of different steer angles and a maximum value Imax of received energy of the plurality of ultrasonic image data, generating composite image data, and generating the composite image An image composition unit for outputting data to the display unit;
With
When generating the first composite image data and the second composite image data that are temporally continuous, the image composition unit generates an average value Iavg of received energy of the second composite image data and the first composite image data. An ultrasonic diagnostic imaging apparatus that calculates an absolute value of a change amount with respect to an average value of received energy and determines a weighting coefficient between the average value Iavg and the maximum value Imax according to the absolute value of the change amount . The weighting coefficient calculated using a function of the absolute value of the amount of change in the average value of the received energy is Wmax, the combined received energy is Icomp,
The ultrasonic image diagnostic apparatus according to claim 7 , wherein the image composition unit generates the composite image data based on a reception energy Icomp calculated based on the following expression .
Icomp = Wmax × Imax + (1−Wmax) × Iavg The image synthesizing unit generates an average value Iavg of received energy of pixels at the same position on the subject and a maximum value Imax of received energy of the pixels of the plurality of ultrasonic image data corresponding to the plurality of different steer angles. The ultrasonic diagnostic imaging apparatus according to claim 7 or 8 , wherein based on this, the composite image data of the pixel is generated . The ultrasonic image diagnosis apparatus according to claim 8 , wherein the function is a function in which the weight coefficient Wmax decreases as the absolute value of the amount of change in the average value of received energy increases. The ultrasound diagnostic imaging apparatus according to claim 8 , wherein the function has at least one of an upper limit value and a lower limit value of a weighting factor Wmax. The image composition unit shows control characteristics of the weighting factor Wmax with respect to the average value Iavg of the received energy and the absolute value of the change amount of the average value of the received energy, and the weighting factor Wmax decreases as the average value Iavg of the received energy increases. Of the three-dimensional functions, the two-dimensional function indicating the weighting factor Wmax for the absolute value of the change amount of the average value of the received energy corresponding to the average value Iavg of the received energy of the second composite image data is used. The ultrasonic diagnostic imaging apparatus according to any one of claims 8, 10, and 11, wherein a weighting coefficient Wmax corresponding to an absolute value of the calculated change amount of the average value of received energy is calculated.