WO2017150355A1

WO2017150355A1 - Ultrasonic diagnostic device and ultrasonic information processing method

Info

Publication number: WO2017150355A1
Application number: PCT/JP2017/006978
Authority: WO
Inventors: 一也高木; 義浩武田
Original assignee: コニカミノルタ株式会社
Priority date: 2016-02-29
Filing date: 2017-02-24
Publication date: 2017-09-08
Also published as: CN108697406B; JP6881629B2; JP2020096894A; JP6662447B2; JPWO2017150355A1; CN108697406A

Abstract

An ultrasonic diagnostic device 100 that applies pressure to a subject, transmits/receives ultrasonic waves to/from a target on the subject, and measures the hardness of the subject by means of an ultrasonic probe 2 that transmits and receives ultrasonic waves. The ultrasonic diagnostic device 100 comprises: a transmission unit 12 that transmits drive signals to the ultrasonic probe 2; a reception unit 13 that processes received signals outputted from the ultrasonic probe 2; a feature value calculation unit 17 that, on the basis of the processed received signals, calculates a plurality of types of feature values that indicate a pressing state for each frame of an elasticity image; an evaluation value calculation unit 18 that calculates an evaluation value from the plurality of calculated feature values and, on the basis of the evaluation value, generates information on a stable segment that comprises frames that have a favorable pressing state; and a display image generation unit 19 that displays, on a display unit 20, the generated stable segment information.

Description

Ultrasonic diagnostic apparatus and ultrasonic information processing method

The present invention relates to an ultrasonic diagnostic apparatus and an ultrasonic information processing method.

2. Description of the Related Art Conventionally, there is an ultrasonic diagnostic apparatus that can observe tissue structure and properties by irradiating an ultrasonic wave inside a subject, receiving the reflected wave, and imaging or analyzing it. In ultrasonic diagnosis, a subject can be examined non-destructively and non-invasively.

Also, in the ultrasonic diagnostic apparatus, a strain elastography technique for imaging a strain distribution generated by applying pressure to a subject of an object using an ultrasonic probe is known. In strain elastography, the hardness of an object can be evaluated from the difference in relative distortion between the object (for example, a tumor) and a reference (for example, fat).

For reliable evaluation of hardness, stable pressure on the subject is required. An ultrasonic diagnostic apparatus is known in which the acquired frame group and the compression direction are linked to such a background, and the selection of a frame that is uniformly compressed by the user is simplified (see Patent Document 1). ). This ultrasonic diagnostic apparatus can display an elastic image of a frame with a good compression direction.

Japanese Patent No. 4769715

However, in the above-described conventional ultrasonic diagnostic apparatus, the pressed state can be confirmed, but basically a single feature amount is displayed. For example, a plurality of compression strengths, compression directions, and the like are displayed. When it is desired to make a comprehensive determination based on the characteristics, it is necessary to switch the display, which may make the operation complicated.

An object of the present invention is to make it possible to easily select a frame of an elastic image with a good pressing state based on a plurality of types of feature amounts.

In order to solve the above-described problem, an ultrasonic diagnostic apparatus according to claim 1 comprises:
An ultrasonic diagnostic apparatus that applies pressure to an object by an ultrasonic probe that transmits and receives ultrasonic waves, transmits and receives ultrasonic waves to the object of the object, and measures the hardness of the object,
A transmission unit for transmitting a drive signal to the ultrasonic probe;
A reception unit for processing a reception signal output from the ultrasonic probe;
A transmission / reception unit for transmitting a drive signal to the ultrasonic probe and processing a reception signal output from the ultrasonic probe;
Based on the processed received signal, a feature amount calculation unit that calculates a plurality of types of feature amounts indicating the pressed state for each frame of the elastic image;
An evaluation value is calculated from the plurality of calculated feature amounts, and based on the evaluation value, an evaluation value calculation unit that generates information of a stable section including a frame having a good pressing state;
A display control unit that displays information on the generated stable section on a display unit.

The invention according to claim 2 is the ultrasonic diagnostic apparatus according to claim 1,
An elastic image generation unit that generates elastic image data based on the received signal,
The feature amount calculation unit generates display information of the calculated plurality of feature amounts,
A storage unit for storing the generated elasticity image data and display information of a plurality of feature amounts;
In a cine mode for selecting and displaying the stored elastic image data, an operation input unit that receives an input of a type of the characteristic amount to be displayed among the plurality of characteristic amounts and an input of a display frame of the elastic image data to be displayed; With
The display control unit includes the stored elasticity image data corresponding to the input display frame, display information of the stored feature amount corresponding to the type of the display frame and the input feature amount, Is displayed on the display unit.

The invention according to claim 3 is the ultrasonic diagnostic apparatus according to claim 2,
The display information of the feature amount includes display information indicating whether or not the display frame is a stable section.

The invention according to claim 4 is the ultrasonic diagnostic apparatus according to

claim

2 or 3,
The evaluation value calculation unit includes a cine frame selection bar that indicates a frame of a stable section among a plurality of frames as information of the generated stable section, a display frame of an elastic image, and a cursor that can be moved and changed. And the initial display frame corresponding to the cursor is set as the display frame in the stable section.

The invention according to claim 5 is the ultrasonic diagnostic apparatus according to any one of claims 2 to 4,
The evaluation value calculation unit includes a cine frame selection bar that indicates a frame of a stable section among a plurality of frames as information of the generated stable section, a display frame of an elastic image, and a cursor that can be moved and changed. Produces
A cursor control unit configured to set a movement speed of the cursor slower when the cursor is within the stable section than when the cursor is outside the stable section;

The invention according to claim 6 is the ultrasonic diagnostic apparatus according to any one of claims 2 to 5,
Based on the evaluation value, the evaluation value calculation unit makes the frame immediately before the freeze operation more likely to be a stable interval than the frame other than immediately before the freeze operation, and generates stable interval information.

The invention according to claim 7 is the ultrasonic diagnostic apparatus according to any one of claims 1 to 6,
An elastic image generation unit that generates elastic image data based on the received signal,
In the live mode, the display control unit displays the generated elasticity image data and the generated stable section information on the display unit.

The invention according to claim 8 is the ultrasonic diagnostic apparatus according to claim 7,
A freeze control unit configured to perform freeze setting when the calculated evaluation value satisfies a predetermined condition.

The invention according to claim 9 is:
An ultrasonic information processing method for applying pressure to an object by an ultrasonic probe that transmits and receives ultrasonic waves and transmitting and receiving ultrasonic waves to the object of the object and measuring the hardness of the object,
Transmitting a drive signal to the ultrasonic probe;
Processing the received signal output from the ultrasound probe;
Based on the processed received signal, calculating a plurality of types of feature amounts indicating a pressed state for each frame of the elastic image;
Calculating an evaluation value from the plurality of calculated feature amounts, and generating information on a stable section including a frame having a good pressing state based on the evaluation value;
Displaying information on the generated stable section on a display unit.

According to the present invention, it is possible to easily select an elastic image frame having a good pressing state based on a plurality of types of feature amounts.

1 is an external view of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. It is a block diagram which shows the function structure of an ultrasonic diagnosing device. It is a conceptual diagram which shows evaluation value calculation from a some feature-value. It is a figure which shows distribution of the evaluation value with respect to time. It is a figure which shows a cine frame selection bar. It is a flowchart which shows an elasticity image display process. It is a figure which shows the display image containing a synthetic elasticity image.

Embodiments and modifications according to an example of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the illustrated example.

(Embodiment)
Embodiments according to the present invention will be described with reference to FIGS. First, with reference to FIG.1 and FIG.2, the apparatus structure of the ultrasound diagnosing device 100 of this Embodiment is demonstrated. FIG. 1 is an external view of an ultrasonic diagnostic apparatus 100 according to the present embodiment. FIG. 2 is a block diagram showing a functional configuration of the ultrasonic diagnostic apparatus 100.

The ultrasonic diagnostic apparatus 100 is an apparatus that displays and outputs an ultrasonic image of a state of a living body tissue of a subject such as a living body of a patient. That is, the ultrasonic diagnostic apparatus 100 transmits ultrasonic waves (transmission ultrasonic waves) to the inside of a subject such as a living body, and transmits reflected ultrasonic waves (reflected ultrasonic waves: echoes) reflected within the subject. Receive. The ultrasound diagnostic apparatus 100 converts the received reflected ultrasound into an electrical signal, and generates ultrasound image data based on this. The ultrasonic diagnostic apparatus 100 displays the internal state in the subject as an ultrasonic image based on the generated ultrasonic image data. The ultrasonic diagnostic apparatus 100 also has a strain elastography function that shows a strain distribution inside the subject to which pressure is applied.

As shown in FIG. 1, the ultrasonic diagnostic apparatus 100 includes an ultrasonic diagnostic apparatus main body 1 having an operation input unit 11 and a display unit 20, an ultrasonic probe 2, and a cable 3. The ultrasonic probe 2 transmits transmission ultrasonic waves to the inside of the subject and receives reflected ultrasonic waves from the inside of the subject. The ultrasonic diagnostic apparatus main body 1 is connected to the ultrasonic probe 2 via the cable 3, and transmits an electric signal drive signal to the ultrasonic probe 2 so that the ultrasonic probe 2 is connected to the inside of the subject. To transmit ultrasonic waves. The ultrasonic diagnostic apparatus main body 1 also receives a reception signal that is an electrical signal generated by the ultrasonic probe 2 in response to the reflected ultrasonic wave from the subject received by the ultrasonic probe 2. Then, ultrasonic image data is generated and displayed using the received signal.

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 apparatus main body 1 and the ultrasonic probe 2 may be performed by wireless communication such as UWB (Ultra Wide Band) instead of wired communication via the cable 3.

As shown in FIG. 2, the ultrasonic diagnostic apparatus body 1 includes, for example, an operation input unit 11, a transmission unit 12, a reception unit 13, a B-mode image generation unit 14, a storage unit 14a, and an elastic image generation unit. 15, a storage unit 15a, an elastic image composition unit 16, a feature amount calculation unit 17, an evaluation value calculation unit 18, a display image generation unit 19 as a display control unit, a display unit 20, a cursor control unit, And a control unit 21 as a freeze control unit.

The operation input unit 11 includes, for example, various switches, buttons, a trackball, a mouse, and a keyboard for an inspector such as a doctor or an engineer to input data such as a command for starting diagnosis or personal information of a subject. Etc., and outputs an operation signal to the control unit 21. The operation input unit 11 includes a touch panel provided on the display screen of the display unit 20.

The transmission unit 12 is a circuit that supplies a drive signal, which is an electrical signal, to the ultrasonic probe 2 via the cable 3 according to the control of the control unit 21 and causes the ultrasonic probe 2 to generate transmission ultrasonic waves. . The transmission unit 12 includes, for example, a clock generation circuit, a delay circuit, a time and voltage setting unit, 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 corresponding to the transmission timing of the drive signal, delays the transmission of the drive signal by the set delay time, and transmits the transmission beam constituted by the transmission ultrasonic waves. This is a circuit for focusing. The time and voltage setting unit is a circuit that sets the voltage of the pulse width of the pulse signal generated from the pulse generation circuit and the voltage of the amplitude. The pulse generation circuit is a circuit for generating a pulse signal as a drive signal in accordance with the time and voltage set by the time and voltage setting unit. 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. Then, the transmission unit 12 performs scanning (scanning) by shifting the driven vibrator in the azimuth direction each time transmission ultrasonic waves are generated.

The receiving unit 13 is a circuit that receives a reception signal, which is an electrical signal, from the ultrasound probe 2 via the cable 3 under the control of the control unit 21 and generates sound ray data by performing signal processing on the reception signal. . 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 a received signal with a preset amplification factor for each individual path corresponding to each transducer. The A / D conversion circuit is a circuit for A / D converting 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 with respect to the A / D converted received signal, and adds these (phasing addition) to generate a sound ray. It is a circuit for generating data.

Under the control of the control unit 21, the B-mode image generation unit 14 performs envelope detection processing, logarithmic amplification, and the like on the sound ray data from the reception unit 13, and adjusts the dynamic range and gain to perform luminance conversion. Thus, B (Brightness) mode ultrasonic image data (B-mode image data) is generated as tomographic image data. In other words, the B-mode image data represents the intensity of the received signal by luminance.

The storage unit 14a is a storage unit configured by a semiconductor memory such as a flash memory. The B mode image generation unit 14 stores the generated B mode image data in association with the frame number (time) in the storage unit 14a as cine frame cine image data in units of frames. The B-mode image generation unit 14 reads out the B-mode image data stored in the storage unit 14 a and outputs the B-mode image data to the elastic image synthesis unit 16 under the control of the control unit 21.

The elastic image generation unit 15 performs an operation on the sound ray data from the reception unit 13 according to the control of the control unit 21, converts it into a distortion amount as elastic information, and performs color mapping to convert the elastic image data. Generate. The size of the image of the elasticity image data generated by the elasticity image generation unit 15 is the size of the ROI (Region Of ： Interest: region of interest) designated and input by the examiner via the operation input unit 11. It is not limited, and it may be the same as the image size of the B-mode image data. The storage unit 15a is a storage unit configured by a semiconductor memory such as a flash memory.

Here, the amount of distortion will be described. The examiner grasps the ultrasonic probe 2 and applies pressure to the body surface of the subject. At this time, the pressure applied from the ultrasonic probe 2 to the subject changes due to the vibration of the examiner himself or the breathing of the subject. For example, it is assumed that the upper end of an object such as a tumor is located at a distance xr in the depth direction (X direction) from the body surface in contact with the ultrasound probe 2 in the subject before the pressure is applied. . Further, it is assumed that the width of the object in the depth direction is L. If compression ρ (stress) is applied to the subject and the object is similarly subjected to compression ρ, the upper end position of the object changes to the distance xs in the depth direction, and the depth of the object. It is assumed that the width of the direction changes so as to be L−ΔL. Then, the distortion amount ε = ΔL / L is obtained by measuring the object in these two states.

More specifically, for example, as described in JP-A-2015- 211733, the elastic image generation unit 15 appropriately stores and reads the sound ray data from the reception unit 13 in the storage unit 15a for each frame. Thus, sound ray data of two frames that are temporally continuous is acquired. Of these two frames, the pressurized state of the subject corresponding to the first signal waveform of the sound ray data of the first frame is set as the first pressurized state, and the second signal waveform of the sound ray data of the second frame is handled. The pressurized state of the subject to be performed is the second pressurized state. Then, the elastic image generation unit 15 extracts a phase difference component at each time between the first signal waveform and the second signal waveform, and according to a correlation between each time and the phase difference component at each time. Then, the distortion difference and the initial phase difference relating to the frequency difference between the first signal waveform and the second signal waveform are calculated, and the distortion amount is calculated based on the distortion difference. The elastic image generation unit 15 calculates the distortion amount for all the pixels, and generates image data including the distortion amount pixels.

Then, the elastic image generation unit 15 generates elastic image data by coloring the image data of the distortion amount by color mapping in which the distortion amount increases in the order of blue → green → yellow → red, for example. However, in the drawing of FIG. 5 to be described later, in the elastic image, the distortion amount is expressed in the order of black → white.

Further, the elastic image generation unit 15 stores the generated elastic image data as cine image data of the cine frame in the storage unit 15a in association with the frame number (time) in units of frames. The elastic image generation unit 15 reads the elastic image data stored in the storage unit 15 a and outputs the elastic image data to the elastic image synthesis unit 16 under the control of the control unit 21.

Under the control of the control unit 21, the elastic image composition unit 16 applies predetermined elasticity image data generated by the elastic image generation unit 15 to the B mode image data generated by the B mode image generation unit 14. To generate composite elastic image data.

Under the control of the control unit 21, the feature amount calculation unit 17 includes the elasticity image data generated by the elasticity image generation unit 15, the sound ray data generated by the reception unit 13, and the information stored in the storage unit 17a. Using at least one, calculate a plurality of types of feature amounts indicating the pressed state of the subject for each frame of the elastic image data, and generate display information of a plurality of feature amounts indicating the calculated feature amounts, The elastic image data and the display information of the plurality of feature amounts are output to the evaluation value calculation unit 18, and the display information of the plurality of feature amounts is stored in the storage unit 17a. The storage unit 17a is a non-volatile storage unit configured by a semiconductor memory such as a flash memory.

As a specific example, an example will be described in which the feature amount calculation unit 17 calculates three types of feature amounts: an elastic image distortion amount d, a distortion amount tempo b, and a confidence value s. However, the type and number of feature amounts calculated by the feature amount calculation unit 17 are not limited to this example.

The feature amount calculation unit 17 uses the elastic image data generated by the elastic image generation unit 15 to calculate the distortion amount d of the elastic image defined by the average distortion amount in the elastic image (ROI) by the following equation (1). calculate.

Where ROI: all pixels of elastic image data, x: distortion amount in variable q of pixels in elastic image, n: number of pixels in ROI.

Further, the feature amount calculation unit 17 uses the elastic image data of a plurality of continuous frames generated by the elastic image generation unit 15 to calculate the sine of the time waveform of the distortion amount of the elastic image (ROI) by the following equation (2). A tempo b of the distortion amount of the elastic image defined by the similarity to the waveform / cosine waveform is calculated. At this time, the feature amount calculation unit 17 appropriately writes and reads the elasticity image data generated by the elasticity image generation unit 15 in the storage unit 17a, and uses it as elasticity image data of a plurality of continuous frames.

However, D (ω) = FFT (D (t)), D (t): time waveform of distortion amount, and t: time / frame number. In the formula (2), when distortion occurs at a constant interval, a specific frequency becomes strong and a numerator becomes large. This state is defined as a state with a good tempo. At this time, the maximum value of the frequency component is calculated in the numerator, but the low frequency component may be excluded from the calculation target of the maximum value so as not to react to a strong pressure, and the medium frequency or high frequency component may be set as the calculation target of the maximum value. The denominator is normalized by the total distortion amount in order to calculate it as a feature quantity independent of the distortion amount. When the tempo b and the distortion amount can be considered at the same time, the tempo b of the elastic image distortion amount is calculated by the following equation (2A).

Further, the feature amount calculation unit 17 uses the sound ray data of the continuous frames generated by the reception unit 13 and calculates the elasticity image defined by the correlation value of the sound ray data of the two consecutive frames according to the following equation (3). A confidence value (restoration rate) s is calculated. At this time, the feature amount calculation unit 17 appropriately writes and reads the sound ray data of each frame generated by the reception unit 13 in the storage unit 17a and uses it as the sound ray data of the continuous frames.
s = AutoCorr (f (x), _fprev (x + Δx)) (3)
Where AutoCorr is an autocorrelation calculation, f (x): signal waveform of sound ray data at a position in the depth direction (depth x) of the current frame, f _prev (x + Δx): a position in the depth direction of the previous frame ( It is a signal waveform of sound ray data at depth x + Δx).

As another feature quantity, the feature quantity calculation unit 17 uses the calculated current and past feature quantities to calculate the current feature quantity calculated by the following equation (4) and the maximum value of the past feature quantities. The degree of similarity p with the past feature amount defined by the error may be calculated. At this time, the feature amount calculation unit 17 appropriately writes and reads the calculated feature amount of each frame in the storage unit 17a and uses it as a past feature amount.
p = | y-y _past | (4)
However, y: current feature value, y _past : the highest value of past feature values. As the feature amounts y and y _past , for example, the distortion amount d is used. However, the feature amounts are not limited to this. As the feature quantities y and y _past , a tempo b or a confidence value s may be used, or a sum of values obtained by multiplying a plurality of feature quantities by a weighting coefficient may be used.

In addition, as another feature amount, the feature amount calculation unit 17 distributes the distortion amount in the horizontal direction (scanning direction) of the pixels of the elastic image data (the sum or average value of the distortion amounts of all the pixels for each column in the depth direction). ), A regression line of the strain distribution is generated, and a score with a perfect score of the slope 0 of the balance line corresponding to the slope of the regression line may be calculated as the feature amount. In this configuration, a balance line may be displayed as the feature amount display information together with the distortion distribution score.

Further, the feature quantity calculation unit 17 generates display information of each calculated feature quantity. For example, the display information of the distortion amount d as the feature amount is display information of a graph indicating the distortion amount from the previous predetermined period to the present. At this time, the feature amount calculation unit 17 appropriately reads out the current and past feature amounts from the storage unit 17a and uses them to generate display information of the feature amounts. The feature amount calculation unit 17 stores the generated display information of the feature amount in association with the frame number (time) in the storage unit 17a for the cine frame.

The evaluation value calculation unit 18 calculates an evaluation value score using a plurality of feature amounts generated by the feature amount calculation unit 17 according to the control of the control unit 21, and generates a cine frame bar based on the evaluation value score. The display information of the plurality of feature amounts generated by the feature amount calculation unit 17 and the generated cine frame bar are output to the display image generation unit 19.

The evaluation value calculation unit 18 calculates the evaluation value score by the following equation (5), for example.
score = w _d · d + w _b · b + w _s · s (5)
Where w _d : weight coefficient of distortion amount d, w _b : weight coefficient of tempo b, w _s : weight coefficient of confidence value s.

FIG. 3 is a conceptual diagram showing evaluation value calculation from a plurality of feature amounts. As illustrated in FIG. 3, the evaluation value calculation unit 18 calculates an evaluation value from a plurality of feature amounts (distortion amount d, tempo b, confidence value s, similarity p) of frames at the same time.

However, the configuration in which the evaluation value calculation unit 18 calculates the evaluation value score by the equation (5) is not limited, and for example, a configuration in which the evaluation value score is calculated by the equation (6) may be employed.
score = d · b · s (6)

The evaluation value calculation unit 18 associates the calculated evaluation value with the frame number (time) and stores it in the storage unit 18a for the cine frame. The storage unit 18a is a non-volatile storage unit configured by a semiconductor memory such as a flash memory.

Further, the evaluation value calculation unit 18 generates a cine frame selection bar having a stable section composed of a group of frames having high evaluation values and temporally continuous based on the current and past evaluation values stored in the storage unit 18a. Here, the generation of the cine frame selection bar will be described with reference to FIGS. 4A and 4B. FIG. 4A is a diagram illustrating a distribution of evaluation values with respect to time. FIG. 4B is a diagram showing a cine frame selection bar 300.

The distribution of evaluation values for each frame with respect to time is shown in FIG. 4A, for example. The time for one frame is, for example, 1/5 to 1/20 [s]. The evaluation value calculation unit 18 calculates a moving average value of evaluation values for a predetermined time (for example, a section of 1 second) over time for the evaluation values of all cine frames. Then, the evaluation value calculation unit 18 generates a cine frame selection bar in which a section for a predetermined time in which the moving average value is equal to or greater than a predetermined threshold is set as a stable section. Note that the moving average value calculation section and the stable section may have different times. The evaluation value calculation unit 18 generates, for example, the cine frame selection bar 300 illustrated in FIG. 4B corresponding to the distribution of evaluation values in FIG. 4A. The cine frame selection bar 300 has a stable section 301 and a normal section 302. The stable section 301 is a stable section indicating a cine frame having a moving average value of evaluation values equal to or greater than a predetermined threshold among all cine frames. The normal section 302 is a normal section indicating a cine frame having a moving average value of evaluation values less than a predetermined threshold among all cine frames.

In the live mode, the display image generation unit 19 generates the composite elastic image data generated by the elastic image combining unit 16 as display image data in the live mode, and the elastic image combining unit 16 generates the display image data in the cine mode. The combined elasticity image data of the cine frame, the display information of the feature amount input from the feature amount calculation unit 17, and the cine frame selection bar input from the evaluation value calculation unit 18 are combined to generate display image data. To do. The display image generation unit 19 converts the generated display image data into an image signal for the display unit 20 and outputs the image signal to the display unit 20.

The display unit 20 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 20 displays an image on the display screen according to the image signal output from the display image generation unit 19.

The control unit 21 includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory), and reads various processing programs such as a system program stored in the ROM to read the RAM. The operation of each part of the ultrasonic diagnostic apparatus 100 is centrally controlled according to the developed program. The ROM is configured by a non-volatile memory such as a semiconductor, and stores a system program corresponding to the ultrasonic diagnostic apparatus 100, a program 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. In order to prevent the diagram from becoming complicated, some control lines from the control unit 21 to each unit are omitted in FIG.

For each unit included in the ultrasonic diagnostic apparatus 100, some or all of the functions of each functional block can be realized as a hardware circuit such as an integrated circuit. The integrated circuit is, for example, an LSI (Large Scale Integration), and the LSI may be referred to as an IC, a system LSI, a super LSI, or an ultra LSI depending on the degree of integration. Further, the method of circuit integration is not limited to LSI, but may be realized by a dedicated circuit or a general-purpose processor, and the connection and setting of FPGA (Field Programmable Gate Array) and circuit cells inside LSI can be reconfigured. A reconfigurable processor may be used. Further, some or all of the functions of each function block may be executed by software. In this case, the software is stored in one or more storage media such as a ROM, an optical disk, or a hard disk, and the software is executed by the arithmetic processor.

Next, the operation of the ultrasonic diagnostic apparatus 100 will be described with reference to FIG. FIG. 5 is a flowchart showing the elasticity image display process.

In the diagnosis of a subject by strain elastography using the ultrasonic diagnostic apparatus 100, as a live mode, the ultrasonic probe 2 is first contacted with the subject to generate B-mode image data and a B-mode image is displayed. The examiner appropriately inputs the elastic image ROI via the operation input unit 11, and the ultrasonic probe 2 applies pressure to the body surface around the subject of the subject.

And in the ultrasonic diagnostic apparatus 100, the control part 21 performs the elasticity image display process shown in FIG. Hereinafter, the direct subject of the process of the step is described as the subject of each step, but the control unit 21 controls the subject of each step.

First, the transmission unit 12 supplies a drive signal to the ultrasonic probe 2 to transmit / receive ultrasonic waves, and the reception unit 13 receives a reception signal from the ultrasonic probe 2 and generates sound ray data ( Step S11). Then, the B-mode image generation unit 14 performs one-frame B-mode image data generation and storage as a cine frame in the storage unit 14a using the sound ray data generated in step S11, and the elastic image generation unit 15 However, using the sound ray data generated in step S11 and the sound ray data of the previous frame stored in the storage unit 15a, elastic image data generation for one frame and storage as a cine frame in the storage unit 15a are performed. The elastic image composition unit 16 synthesizes the generated B-mode image data and elastic image data to generate one frame of synthetic elastic image data (step S12).

Then, the feature amount calculation unit 17 uses the sound ray data obtained in step S11, the elastic image data obtained in step S12, and past information stored in the storage unit 17a, so that the feature amount (distortion amount d, Tempo b, confidence value s) is calculated, and display information of each feature quantity is generated and stored in the storage unit 17a (step S13). Then, the evaluation value calculation unit 18 calculates an evaluation value score of the feature amount using the feature amount calculated in step S13, and generates information on a stable section in the cineframe selection bar and stores it in the storage unit 18a. (Step S14).

Then, the display image generation unit 19 generates one frame of display image data from the one frame of synthetic elastic image data generated in step S12, and displays the display image on the display unit 20 (step S15). The examiner can diagnose the hardness of an object such as a tumor in the synthetic elastic image by visually observing the synthetic elastic image displayed on the display unit 20.

And the control part 21 discriminate | determines whether the freeze input was performed from the examiner via the operation input part 11 (step S16). If the freeze input has not been made (step S16; NO), the process proceeds to step S11. When the freeze input is made (step S16; YES), the cine mode is started, and the control unit 21 assigns the initial display frame number of the cine image data to the B-mode image generation unit 14, the elastic image generation unit 15, the feature amount. The setting is output to the calculation unit 17 and the evaluation value calculation unit 18 (step S17). The initial display frame is, for example, a cine frame immediately before freezing among a plurality of cine frames.

The B-mode image generation unit 14 reads out the B-mode image data of the input display frame number from the storage unit 14a and outputs it to the elastic image synthesis unit 16, and the elastic image generation unit 15 inputs the display frame number. Are read from the storage unit 15a and output to the elastic image composition unit 16, and the elastic image composition unit 16 synthesizes the input B-mode image data and the elastic image data to generate composite elastic image data ( Step S18).

Then, the feature amount calculation unit 17 reads out the display information of the feature amount of the type for which the input display frame number is being set (initially initial setting) from the storage unit 17a and outputs it to the display image generation unit 19 (Step S1). S19). The default feature amount is, for example, a distortion amount d. Then, the evaluation value calculation unit 18 reads the stable section information from the storage unit 18a, and generates a cine frame selection bar having a cursor at a position corresponding to the input display frame number based on the stable section information. It outputs to the display image generation part 19 (step S20).

The display image generation unit 19 generates display image data by combining the composite elastic image data of the input display frame number, the display information of the feature amount, and the cine frame selection bar, and the display image is displayed on the display unit 20. It is displayed (step S21). And the control part 21 discriminate | determines whether the cursor movement input was carried out from the examiner via the operation input part 11 (step S22). When the cursor movement input is made (step S22; YES), the control unit 21 uses the changed display frame number corresponding to the cursor movement of step S22 as the B-mode image generation unit 14, the elastic image generation unit 15, and the feature amount. The setting is output to the calculation unit 17 and the evaluation value calculation unit 18 (step S23), and the process proceeds to step S18.

When the cursor movement input has not been made (step S22; NO), the control unit 21 determines whether or not a feature amount change input has been made by the inspector via the operation input unit 11 (step S24). When a feature amount change input is made (step S24; YES), the feature amount calculation unit 17 reads out display information of the type of feature amount corresponding to the feature amount after the change in step S24 from the storage unit 17a and generates a display image. It outputs to the part 19 (step S25), and transfers to step S21. If the feature amount change input has not been made (step S24; NO), the elastic image display process is terminated.

FIG. 6 is a diagram showing a display image 200 including a synthetic elastic image 210. For example, as shown in FIG. 6, the display image 200 of the display frame number is displayed on the display unit 20 in the cine mode. The display image 200 includes a composite elasticity image 210, a cine frame selection bar 300A, a frame number display field 310, feature amount display information 400, and a feature amount switching button 410.

The composite elastic image 210 is a composite image of a B mode image 211 based on the B mode image data of the display frame number and an elastic image 212 based on the elastic image data of the display frame number. The cine frame selection bar 300A has a stable section 301A, a normal section 302A, and a cursor 303.

The stable section 301A is a part of a bar indicating a stable section among cine frames of all cine image data. The normal section 302A is a part of a bar indicating the normal section among all cine frames. The cursor 303 is an operation display element that is arranged at the position of the display frame number corresponding to the composite elastic image 210 and receives a selection input of a cine frame to be displayed from the examiner via the operation input unit 11, and is a stable section 301A. In addition, movement change input can be made to the left and right on the normal section 302A. The frame number display column 310 is a display column indicating the frame number of the order of the composite elastic image 210 (cursor 303) out of the number of cine frames of all cine image data. The display colors of the stable section 301A and the normal section 302A are preferably different.

The feature amount display information 400 is a display column for a distortion amount d as a default feature amount. The feature amount display information 400 includes a graph part 401, a reference area 402, and a frame part 403. The graph unit 401 is a part showing a graph of the distortion amount d with time with the horizontal axis representing time, the vertical axis representing the distortion amount d of the feature amount, and the center of the vertical axis of the feature amount display information 400 being the reference value. is there. The right end of the graph part 401 is set as the distortion amount d of the frame immediately before freezing. The reference area 402 is an area indicating an appropriate range of the distortion amount d from the center of the vertical axis of the feature amount display information 400. That is, if the graph portion 401 is within the reference region 402, it indicates that the distortion amount d of the portion is appropriate. If the graph portion 401 protrudes from the reference region 402, the distortion amount d of the portion is not appropriate. Show.

The frame part 403 is a frame part of the feature amount display information 400, and the display color is set to whether or not the cine frame corresponding to the cursor 303 is a stable section. For example, when the cine frame corresponding to the cursor 303 is a stable section, the frame portion 403 is displayed in the same display color as that of the stable section 301A.

The feature amount switching button 410 is an operation display element that receives a switching input of the type of feature amount displayed by the feature amount display information 400 displayed from the examiner via the operation input unit 11. For example, every time the feature amount switching button 410 is pressed, the feature amount of the feature amount display information 400 is switched in the order of distortion amount d → tempo b → reliable value s → distortion amount d →. Corresponding to step S <b> 24, when the feature amount switching button 410 is touch-inputted via the operation input unit 11, the control unit 21 outputs the switched display feature amount information to the feature amount calculation unit 17. The feature amount calculation unit 17 reads out display information of the feature amount corresponding to the input display feature amount information with the same display frame number from the storage unit 17a and outputs the display information to the display image generation unit 19. The display image generation unit 19 generates display image data by combining the composite elastic image data having the same display frame number, the display information of the feature value after switching, and the cine frame selection bar, and displays the display image on the display unit 20. Let Note that the display information of the feature amount is not limited to the display format of the graph over time, but may be another display format such as a numerical display of the feature amount.

Corresponding to step S22, when a display cine frame is selected and input by moving the cursor 303 via the operation input unit 11, the composite image data, the cine frame selection bar corresponding to the display frame number after selection, A display image including the display information of the feature value after switching is displayed.

As described above, according to the present embodiment, the ultrasound diagnostic apparatus 100 supplies the drive signal to the ultrasound probe 2, processes the reception signal output from the ultrasound probe 2, and processes the received signal. And calculating a plurality of types of feature amounts indicating the pressing state for each frame of the elastic image, calculating an evaluation value from the calculated plurality of feature amounts, and based on the evaluation value, the pressing state is good A cine frame selection bar is generated as information of a stable section composed of frames, and the generated cine frame selection bar is displayed on the display unit 20.

For this reason, the inspector can visually check the elastic image frame in the stable section in a good pressed state based on a plurality of types of feature values, and can easily select it.

Further, the ultrasonic diagnostic apparatus 100 generates elasticity image data based on the received signal, generates display information of the calculated plurality of feature amounts, and generates the generated elasticity image data and the display information of the plurality of feature amounts. Stored in the

storage units

15a and 17a, and in cine mode, accepts an input of the type of feature quantity to be displayed among a plurality of feature quantities and an input of a display frame of elastic image data to be displayed, and corresponds to the input display frame The display unit 20 displays the stored elasticity image data and the display information of the stored feature value corresponding to the type of the display frame and the input feature value. Therefore, the inspector can visually recognize the feature amount of the displayed cineframe.

Also, the feature amount display unit 400 includes a frame unit 403 that indicates whether or not the display frame is a stable section by a display color. For this reason, the inspector can easily recognize the feature amount of the displayed cine frame together with the information indicating whether or not it is a stable section.

(Modification)
A plurality of modifications of the above embodiment will be described in order.

In the first modification, in the ultrasonic diagnostic apparatus 100, when the cine mode is started, the control unit 21 displays the display frame number of the cine image data to be displayed in the initial setting corresponding to the cursor, and displays the cine frame other than immediately after the freeze. The frame number is set. For example, the control unit 21 is configured to set the display frame number of cine image data to be displayed at the start of the cine mode to the frame number of a cine frame within the stable section (for example, the center of the stable section). According to this configuration, information on the cine frame in the stable section important for diagnosis can be confirmed first, and the diagnosis can be performed accurately and the diagnosis time can be shortened.

In the second modification example, in the ultrasonic diagnostic apparatus 100, the control unit 21 is within the normal section for the same movement operation from the examiner via the operation input unit 11 in the cursor movement display of the cine frame selection bar. In this configuration, the moving speed of the cursor in the stable section is set slower. According to this configuration, it is easy to select a display cine frame in a stable section important for diagnosis.

The third modified example is a configuration in which the evaluation value calculation unit 18 makes it easier to set the cine frame immediately before the freeze of the cine frame selection bar as a stable section than the cine frame other than immediately before the freeze in the ultrasound diagnostic apparatus 100. is there. For example, a configuration in which an evaluation value of a cine frame immediately before freezing is multiplied by a predetermined coefficient of 1 or more, a configuration in which a threshold for determining a stable interval with respect to a moving average value of evaluation values including an evaluation value of a cine frame immediately before freezing is reduced There is. According to this configuration, it is possible to easily set the latest frame that has been freeze-operated by the examiner as determined to be important as a stable interval important for diagnosis, and the diagnosis can be performed more accurately.

In the fourth modification example, in the ultrasound diagnostic apparatus 100, the evaluation value calculation unit 18 performs a stable interval based on an evaluation value obtained by calculating a moving average value corresponding to a predetermined number of frames up to the present time in the live mode. The normal section information is output to the display image generation unit 19, and the display image generation unit 19 displays the input stable section information together with the live composite image data on the display unit 20. According to this configuration, even in the live mode, the inspector can visually recognize a frame of an elastic image in a stable section with a good pressing state based on a plurality of types of feature amounts.

In the fifth modification example, in the ultrasound diagnostic apparatus 100, the evaluation value calculation unit 18 performs a stable interval based on an evaluation value obtained by calculating a moving average value corresponding to a predetermined number of frames up to now during the live mode. In this configuration, information on the normal section is output to the control unit 21. Further, the control unit 21 determines whether or not the evaluation value satisfies a predetermined condition set in advance, and automatically sets the freeze when the predetermined condition is satisfied. The predetermined condition is, for example, that the moving average value of the evaluation values is equal to or more than a second predetermined threshold different from the first predetermined threshold for determining the stable section. According to this configuration, even in the live mode, the examiner can easily visually confirm the elastic image frame important for the diagnosis corresponding to the stable section as the elastic image of the still image frame.

Note that the descriptions in the above-described embodiments and modifications are examples of the preferred ultrasonic diagnostic apparatus and ultrasonic information processing method according to the present invention, and the present invention is not limited to this. For example, it is good also as a structure which combines at least 2 of the said embodiment and modification.

In the embodiment and the modification described above, the stable section in the cineframe selection bar is set to the same color. However, the present invention is not limited to this. The stable section may have a different display color according to the height of the evaluation value. For example, the display color density of the stable section may be increased as the evaluation value increases. According to this configuration, the height of the evaluation value of the stable section can be easily confirmed, and each stable section can be easily identified particularly when there are a plurality of stable sections in the cine frame selection bar.

In the above embodiment, the image data indicating the strain amount as the elasticity data is generated and used as the elasticity image data by the strain elastography. However, the present invention is not limited to this. For example, image data indicating shear wave velocity as elastic data by shear wave elastography (Shear Wave Elastography) may be generated and used as elastic image data.

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

As described above, the ultrasonic diagnostic apparatus and ultrasonic information processing method of the present invention can be applied to ultrasonic diagnosis using elastic images.

DESCRIPTION OF SYMBOLS 100 Ultrasonic diagnostic apparatus 1 Ultrasonic diagnostic apparatus main body 11 Operation input part 12 Transmission part 13 Reception part 14 B-mode

image generation part

14a, 15a, 17a, 18a Storage part 15 Elastic image generation part 16 Elastic image synthesis part 17 Feature-value calculation Unit 18 evaluation value calculation unit 19 display image generation unit 20 display unit 21 control unit 2 ultrasonic probe 2a transducer 3 cable

Claims

An ultrasonic diagnostic apparatus that applies pressure to an object by an ultrasonic probe that transmits and receives ultrasonic waves, transmits and receives ultrasonic waves to the object of the object, and measures the hardness of the object,
A transmission unit for transmitting a drive signal to the ultrasonic probe;
A reception unit for processing a reception signal output from the ultrasonic probe;
Based on the processed received signal, a feature amount calculation unit that calculates a plurality of types of feature amounts indicating the pressed state for each frame of the elastic image;
An evaluation value is calculated from the plurality of calculated feature amounts, and based on the evaluation value, an evaluation value calculation unit that generates information of a stable section including a frame having a good pressing state;
An ultrasonic diagnostic apparatus comprising: a display control unit configured to display information on the generated stable section on a display unit.
An elastic image generation unit that generates elastic image data based on the received signal,
The feature amount calculation unit generates display information of the calculated plurality of feature amounts,
A storage unit for storing the generated elasticity image data and display information of a plurality of feature amounts;
In a cine mode for selecting and displaying the stored elastic image data, an operation input unit that receives an input of a type of the characteristic amount to be displayed among the plurality of characteristic amounts and an input of a display frame of the elastic image data to be displayed; With
The display control unit includes the stored elasticity image data corresponding to the input display frame, display information of the stored feature amount corresponding to the type of the display frame and the input feature amount, The ultrasonic diagnostic apparatus according to claim 1, wherein: is displayed on the display unit.
The ultrasonic diagnostic apparatus according to claim 2, wherein the display information of the feature amount includes display information indicating whether or not the display frame is a stable section.
The evaluation value calculation unit includes a cine frame selection bar that indicates a frame of a stable section among a plurality of frames as information of the generated stable section, a display frame of an elastic image, and a cursor that can be moved and changed. The ultrasonic diagnostic apparatus according to claim 2, wherein an initial setting display frame corresponding to the cursor is set as a display frame in the stable section.
The evaluation value calculation unit includes a cine frame selection bar that indicates a frame of a stable section among a plurality of frames as information of the generated stable section, a display frame of an elastic image, and a cursor that can be moved and changed. Produces
The ultrasound according to any one of claims 2 to 4, further comprising: a cursor control unit configured to set a moving speed of the cursor slower when the cursor is in the stable section than when the cursor is outside the stable section. Diagnostic device.
3. The evaluation value calculation unit, when calculating the evaluation value, generates information of a stable section by relatively increasing an evaluation value of a frame immediately before the freeze operation than a frame other than immediately before the freeze operation. The ultrasonic diagnostic apparatus according to any one of 5.
An elastic image generation unit that generates elastic image data based on the received signal,
The super display according to any one of claims 1 to 6, wherein the display control unit displays the generated elasticity image data and the generated stable section information on the display unit in a live mode. Ultrasonic diagnostic equipment.
The ultrasonic diagnostic apparatus according to claim 7, further comprising a freeze control unit configured to perform freeze setting when the calculated evaluation value satisfies a predetermined condition.
An ultrasonic information processing method for applying pressure to an object by an ultrasonic probe that transmits and receives ultrasonic waves and transmitting and receiving ultrasonic waves to the object of the object and measuring the hardness of the object,
Transmitting a drive signal to the ultrasonic probe;
Processing the received signal output from the ultrasound probe;
Based on the processed received signal, calculating a plurality of types of feature amounts indicating a pressed state for each frame of the elastic image;
Calculating an evaluation value from the plurality of calculated feature amounts, and generating information on a stable section including a frame having a good pressing state based on the evaluation value;
Displaying the generated information of the stable section on a display unit.