JP2001017434A - Ultrasonograph - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability on the shift prediction of an ultrasonic probe in the expansion display of an inspection width. SOLUTION: For the expansion display of an inspection width in this device, a user generates the upper limit value and lower limit value of an effective image size in the depth direction for each shift distance of an ultrasonic probe in advance and stores them in memories 223, 224, respectively. A B-image is fed from a scan converter section 1 and sent to a work memory 222 via a B-image frame buffer memory 21. A CPU 221 predicts the shift distance and direction of the probe based on the sent B-image data and synthesizes an image. The CPU 221 reads the upper limit value and lower limit value from the memories 223, 224 in response to the total shift distance of the ultrasonic probe from the start position to the previous frame and uses only the image data in this range, thereby the error occurrence probability in a shift quantity estimation stage is suppressed low, and the reliability on the shape of the formed image can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus having a digital image signal processing section and a function of enlarging and displaying a subject width, and more particularly, to an effective data range for each cumulative moving distance of an ultrasonic probe. By changing the range to the set range, the reliability at the time of image construction is improved.

[0002]

2. Description of the Related Art Conventionally, a visual field expanding function is disclosed in
No. 8 is known. The test width enlarged display function predicts and estimates the moving vector amount of the ultrasonic probe from continuous B images obtained by moving the ultrasonic probe in the long axis direction as shown in FIG. A continuous B image is connected, an enlarged two-dimensional ultrasonic image is reconstructed, and an image having an enlarged test width is displayed.

[0003]

However, in the above-described conventional enlarged display function of the subject width, the effective data size of the depth direction and the subject width of the ultrasound probe is fixed, and the bone is located near the surface of the ultrasound probe. If there is a strong reflector such as the above, ultrasonic waves are reflected by the strong reflector in a portion deeper than the strong reflector, so that the number of echoes is reduced and the image becomes dark.

[0004] When signal processing for the subject width enlarged display function is performed using this data, the correlation with the previous frame is weakened, and the reliability in the movement amount estimation process is reduced. If the reliability is low, there is a problem that the possibility that the shape of the joined and combined enlarged images does not match the actual shape increases.

The present invention solves the above-mentioned conventional problem, and narrows or widens the effective data range in the depth direction used when synthesizing an image at a position of a strong reflector which can be predicted in advance by a user. It is an object of the present invention to provide an excellent ultrasonic diagnostic apparatus capable of improving the reliability of image synthesis by changing the effective data range for each moving distance of the cumulative ultrasonic probe and making it optimal. Aim.

In order to enlarge the display of the subject width in real time, half of the normal B image is the latest image as shown in FIG. 7, and the rest is reconstructed from images obtained before that. The enlarged test width display image is displayed. Therefore, the number of portions displayed as the latest image is smaller than that of the B image obtained by ordinary probe scanning. When scanning the probe, the user sees the subject and the probe and cannot see the ultrasound image at the same time, so he or she will look at either, but it is usual to scan while looking at the image. It is. Therefore, when the user is moving the probe, it is difficult to obtain information such as whether the probe surface is moving away from the subject, and there is a problem that it is difficult to scan the probe.

Accordingly, the present invention solves the above-mentioned conventional problems. When displaying an image by the visual field enlarging function, the entire B image is displayed simultaneously with the image by the visual field enlarging function, so that the position of the probe and the subject can be reduced. An object of the present invention is to provide an ultrasonic diagnostic apparatus capable of facilitating probe scanning because much information can be obtained by a user.

[0008]

In order to solve the above problems, the present invention has a user interface so that a user can change the effective data range in the depth direction for each moving distance of the ultrasonic probe, The set valid data range is stored in the memory in advance. In the subject width enlargement display function, images are synthesized using the results from the prediction and estimation of the ultrasonic probe movement amount, which is calculated in real time, but the cumulative movement from the processing start position of the subject width enlargement display function is performed. The reliability of image construction is improved by changing the range of valid data used for predicting and estimating the movement of the ultrasonic probe according to the distance.

Further, by simultaneously displaying the image by the visual field enlarging function and the entire B image, the scanning of the probe can be facilitated.

As described above, by changing the effective data range to the range set by the user for each cumulative moving distance of the ultrasonic probe, the reliability at the time of constructing an image is improved. In addition, it is possible to provide an ultrasonic diagnostic apparatus that can easily perform probe scanning by simultaneously displaying the entire B image together with the enlarged display image of the subject width.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a scan converter unit for displaying a B image of an ultrasonic echo signal obtained from an ultrasonic probe, a subject width enlargement processing unit having an image display memory, A display control unit, a display unit, and a memory in which a user presets and saves an upper limit value and a lower limit value in a depth direction used when performing image processing for each ultrasonic probe moving distance, and the upper limit value and the lower limit value An ultrasonic diagnostic apparatus having a user interface for setting values by a user, wherein the user previously sets a valid data range in the depth direction for each moving distance of the ultrasonic probe and is calculated in real time. Predicting and estimating ultrasonic probe movement according to its set effective data range in the depth direction for each ultrasonic probe movement distance An effect that it is possible to improve the reliability of the estimation.

According to a second aspect of the present invention, there is provided a memory for storing an upper limit value and a lower limit value of image data in the depth direction for each ultrasonic probe moving distance set in advance by a user;
The ultrasonic probe movement prediction and estimation processing is performed using image data within the effective image data range defined by the upper and lower limits in the depth direction set by the user according to the total moving distance of the ultrasonic probe. 2. The ultrasonic diagnostic apparatus according to claim 1, further comprising a detection width enlargement processing unit, wherein the effective depth direction data range for each ultrasonic probe movement distance is set in advance before the user performs the measurement width enlargement display function. It is possible to improve the reliability of the arithmetic processing by performing ultrasonic probe movement prediction and estimation calculation according to the effective data range set in advance for each ultrasonic probe movement distance calculated in real time. Has an action.

According to a third aspect of the present invention, in the subject width enlarged display function, the user is provided with a user interface for performing a calculation for the image processing again, and the recalculation is performed without being restricted by the calculation processing time. The ultrasonic diagnostic apparatus according to claim 1, wherein the recalculation is performed without being restricted by the calculation processing time, and has an effect that the reliability of image construction can be improved.

According to a fourth aspect of the present invention, there is provided a scan converter unit for displaying a B image of an ultrasonic echo signal obtained from an ultrasonic probe, a visual field expansion processing unit having an image display memory, a display control unit, It has a display unit, and in the field-of-view enlargement processing unit, a plurality of B-images are joined together and synthesized, and the B-image and the B-image are simultaneously transferred to the image display memory, so that the subject-width-enlarged display image by the field-of-view enlargement function And an ultrasound diagnostic apparatus that simultaneously displays the B image and the B image in separate windows. The ultrasound diagnostic apparatus displays the B image generated by the scan converter unit and the enlarged display image of the subject width reconstructed from the B image by the visual field expansion processing unit. The image is simultaneously transferred to the display memory in the processing unit, and the enlarged view image and the B image are simultaneously displayed in separate windows on the display unit via the display control unit. The Rukoto, has the effect of scanning of the probe can be easily.

According to a fifth aspect of the present invention, there is provided an ultrasonic diagnostic apparatus according to the fourth aspect, wherein the B image is simultaneously displayed as a separate image in separate windows on the same monitor together with the image obtained by the visual field enlarging function. The device has the effect that the user can obtain information on the positional relationship between the probe and the subject, that is, whether the probe surface is moving away from the subject, thereby facilitating scanning of the probe. .

According to a sixth aspect of the present invention, the upper limit value and the lower limit value of the image data in the depth direction for each ultrasonic probe moving distance set in advance are stored in the memory in order to perform the enlarged display of the subject width. And moving the ultrasonic probe using image data within the effective image data range defined by the upper and lower limits in the depth direction set by the user according to the total moving distance of the ultrasonic probe. Ultrasound probe movement estimation processing method to perform the estimation processing, before the user performs the subject width enlarged display, in advance, set an effective depth direction data range for each ultrasonic probe movement distance,
By performing ultrasonic probe movement prediction and estimation calculation in accordance with an effective data range set in advance for each ultrasonic probe movement distance calculated in real time, there is an effect that the reliability of the arithmetic processing can be improved.

According to a seventh aspect of the present invention, in order to perform the enlarged display of the detected width, it is possible to perform an input for performing a calculation for image processing again by a user interface. This is an ultrasonic diagnostic method including an ultrasonic probe movement estimation processing method, and has an effect that reliability can be improved by recalculating.

According to the present invention, the enlarged width of the subject to be detected is displayed in real time, and the enlarged subject width image is synthesized by image synthesis. Ultrasound diagnostic method that recalculates without restriction on processing time, recovers the limit of calculation accuracy by real-time processing, and recalculates when the user feels something wrong with the image constructed from the enlarged width of the subject. By performing the processing and applying the calculation time to the processing time in the real-time processing, there is an effect that the reliability of image construction can be improved.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

(First Embodiment) FIG. 1 is a block diagram showing a first embodiment of the present invention. In FIG. 1, a scan converter unit 1 generates a B image from an ultrasonic echo signal obtained from an ultrasonic probe, and outputs the B image data to a visual field expansion processing unit 2.

The field-of-view expansion processing unit 2 includes a B image Frame Buffer
A memory 21, an image processing unit 22 for performing movement vector calculation, image reconstruction, that is, image joining, and a display memory unit
23 and B transmitted from the scan converter unit 1.
The image data is temporarily stored in the B image FrameBuffer memory 21.

The image processing unit 22 includes a CPU 221 and a work memory 22.
2. It is composed of an upper limit memory 223 and a lower limit memory 224, receives B image data from the B image Frame Buffer memory 21, and transfers it to the image data work memory 222.
The moving amount and direction of the ultrasonic probe between one frame before and the current frame image are predicted and estimated using the image data, and the image is synthesized based on the result.

The image synthesized by the image processing section 22, that is, the enlarged display image to be detected is output to the display memory 23. The image data in the display memory 23 is displayed as an image on the display unit 4 via the display control unit 3. The upper limit memory 223 and the lower limit memory 224 are used for predicting and estimating the moving amount of the ultrasonic probe for each of the total moving distances of the ultrasonic probe that can be set in advance by the user before using the enlarged display width function. This is a memory for storing the upper limit value and the lower limit value of the effective image range to be used. The above-described data transfer, ultrasonic probe movement prediction, estimation, and image synthesis are all performed by the CPU 221 of the image processing unit 22.

The operation of the ultrasonic diagnostic apparatus configured as described above will be described with reference to FIG.

FIG. 2 is a diagram also showing where an image is generated on a block according to the first embodiment of the present invention. In FIG. 2, a B image is generated in the scan converter unit 1. The generated B image is continuously output to the B image Frame Buffer memory 21 of the visual field expansion processing unit 2. This B image data may or may not be synchronized with the display synchronization signal. However, since the start and end timings of one frame of image data need to be recognized by the visual field expansion processing unit 2, the B image data is displayed vertically. , The case of synchronizing with the horizontal synchronization signal will be described. When one frame of image data is stored in the B image frame buffer memory 21, the data is transferred to the work memory 222 in the image processing unit 22.

In the image processing section 22, the ultrasonic probe movement amount prediction and estimation from one frame before, and image processing from the result to image joining are performed by the subject width expansion function (FIG. 3). Here, the effective image range in the depth direction is set in advance for each ultrasonic probe movement distance from the position of the ultrasonic probe when the subject width expansion function is started, and the upper and lower limit data of the effective image range is It is assumed that they are stored in the upper limit memory 223 and the lower limit memory 224, respectively.

The new frame image is stored in the work memory 22.
When the image data is transferred to 2, the prediction, estimation, and synthesis of the image of the ultrasonic probe are performed using the image data.
When performing the ultrasound probe movement amount prediction and estimation, the upper limit value and lower limit value data of the effective image range corresponding to the cumulative ultrasound probe movement amount up to one frame before are stored in the upper limit memory 223,
The effective image range is taken out from the lower limit value memory 224 and used for predicting and estimating the movement of the ultrasonic probe. The movement amount is predicted and estimated using the data within the effective range. Then, using the result, image joining processing is performed. The joined image, that is, the enlarged image of the subject width is output to the display memory 23.

Since the address on the display memory 23 corresponds to the display position of the image on the display unit 4, the address to which the address is to be transferred is determined according to the image display format. The display controller 3 selects a signal source to be displayed. When the view expansion function is operating, the display memory 23 in the view expansion processor 2 is selected as a signal source. Then, the sum of the latest movement amounts is the movement amount when the next image processing is performed, and is used for calculating the effective image range when processing the next frame image.

FIG. 4 shows an example of a user interface for previously storing in memory a maximum value and a minimum value indicating an effective image range used for predicting and estimating the movement of an ultrasonic probe set in advance by a user. Show. FIG. 4 shows an example in the case of a maximum of 60 cm. The setting is to narrow the region where the ultrasonic signal by the strong reflector or the like becomes weak in the depth direction. Simply reducing the number of valid data for all travel distances reduces the number of usable data, which also leads to a reduction in reliability. Therefore, it is desirable not to provide a narrow range as much as possible.

In the memory that can change the number of data in the effective depth direction, the maximum value determined by the maximum movement amount / minimum movement amount resolution is the maximum, and interpolation calculation is performed after the ultrasonic probe movement amount is obtained. To do that, a memory of about 10 points is enough. Here, in the image processing unit 22,
Work memory 222, upper limit memory 223, lower limit memory 224
Are described separately, but as described above, the upper limit memory 22
3. Since the lower limit memory 224 does not require a large-capacity memory, it can be treated as a part of the work memory.

FIG. 5 shows the operation of the image processing section 22. First, B image data (80) is stored in the work memory 222 in the image processing unit 22.
Is transferred (90), the latest ultrasonic probe movement distance is calculated from the previous calculation, that is, the ultrasonic probe movement amount obtained from the image one frame before and the cumulative ultrasonic probe movement amount up to that time. (95).

The upper limit memory 223 and the lower limit memory 2 set by the user based on the moving distance of the ultrasonic probe.
From 24, the effective image range in the depth direction is obtained by interpolation calculation. If the upper limit memory and the lower limit memory can be sufficiently large, the interpolation calculation becomes unnecessary, and the immediate value is read from the memory (91).

The number of data for predicting and estimating the movement of the ultrasonic probe in the current frame image is determined from the valid data range, and A and B in (83) are the upper limit value and the lower limit value, respectively. The ultrasonic probe movement amount is predicted and estimated using data within this range (92).

Then, the calculation of the moving amount of the ultrasonic probe is completed, and the moving angle and the moving distance are calculated (93). Images (8
As shown in 4), the latest B image and the B image one frame before are superimposed and image-combined (94). Thus, an image (81) is obtained.

By repeatedly performing this, the enlarged display image (81) is displayed in real time.

The larger the effective image area, the higher the reliability. However, if a strong reflector such as a bone is present where the ultrasound probe scans, the correlation between the preceding and subsequent frames at that portion is weakened, and the reliability of the ultrasound probe movement prediction and estimation stage is reduced.

For this reason, in some cases, the image may be rotated, or it may be estimated that it has moved beyond the actual moving distance, and the images may be synthesized, even though it is moved flat.

[0038] Therefore, if the user knows in advance that there is a factor that lowers the reliability, the reliability is improved by removing the factor that lowers the reliability.

(Second Embodiment) In the second embodiment of the present invention, an error occurs at the stage of calculating the ultrasonic probe movement vector in the real-time processing, and the shape of the synthesized image is apparent from the actual shape. If the key is too far away, a key for redoing the calculation of the movement vector is provided, and when the key is pressed, a recalculation for image synthesis is performed from the beginning using the image data stored in the work area.

In this case, a portion where the calculation accuracy is sacrificed for realizing the real-time processing, for example, a block size for detecting the movement at the block level is increased, and the standard deviation of the image data is reduced. When the level of the entire image is almost constant, the size of the ultrasound probe in the depth direction for performing image processing is reduced, thereby estimating the moving distance and moving direction of the ultrasonic probe calculated from the image data. Improve reliability.

According to the second embodiment of the present invention, the user sets the upper limit and lower limit of the effective image data for each moving distance of the ultrasonic probe in advance, and stores the upper limit memory and the lower limit memory, respectively. Can be stored at

When predicting and estimating the moving amount and direction of the ultrasonic probe from the current frame image in the subject width enlarging function, the upper limit memory and the lower limit are stored for each ultrasonic probe moving distance determined so far. Information on the effective image data range is read from the value memory, and the ultrasound probe movement prediction and estimation can be performed using the data in the range.

By repeating this, the reliability of the ultrasonic probe movement prediction and estimation required for each frame image is improved, and the frame images are connected.
It is possible to reduce the error occurrence probability of the shape of the synthesized image with the enlarged test width.

That is, the upper limit value is set so as to reduce the influence of the strong reflector, which is a foreseeable error occurrence factor.
By setting a lower limit in advance and using the data in image processing, reliability in image processing can be improved.

Further, by allowing recalculation to be performed after real-time processing and improving the calculation accuracy,
The effect of the strong reflector can be reduced. That is,
The reliability of processing in image processing can be improved.

(Third Embodiment) The operation of the third embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 4 is a diagram showing where an image is generated on a block. In FIG.
An image is generated. The generated B image is continuously output to the B image Frame Buffer memory 21 of the visual field expansion processing unit 2. When one frame of image data is stored in the B image FrameBuffer memory 21, the image processing unit 22 performs a moving amount vector calculation and performs an image joining process using the result.

The image processing section 22 is generally composed of a microprocessor and a memory. The connected images are output to the display memory 23. At this time, the image processing unit 22 simultaneously transfers the B image data in the B image Frame Buffer memory 21 to the display memory 23.

Since the address on the display memory 23 corresponds to the display position of the image on the display unit 4, the address on which the image is transferred is determined according to the image display format. The display controller 3 selects a signal source to be displayed. When the view expansion function is operating, the display memory 23 in the view expansion processor 2 is selected as a signal source. Therefore, the B image on the display memory 23 and the enlarged display image of the subject width are simultaneously displayed on the display unit 4. FIG. 8 shows a display example at that time.

As described above, according to the third embodiment of the present invention, the image processing unit 22 of the visual field enlarging processing unit 2 generates an enlarged display image to be inspected, and B
Since the image is transferred to the display memory 23 together with the enlarged display image of the subject, the B image and the enlarged display image of the subject can be simultaneously displayed on a single monitor in separate windows.
Obtaining information such as whether the probe is moving away from the subject can facilitate scanning of the probe.

At this time, the function of the display controller unit 3 is to switch the signal source of the image. However, when the signal source is switched in accordance with the display position of the image, the output of the scan converter unit 1 and the display in the visual field expansion processing unit are changed. Since the switching of the output of the memory 23 is switched by the display control unit 3, it is not necessary to transfer the B image data to the display memory 23 by the image processing unit 22, and the processing time is shortened, so that the frame rate is increased. Having.

Also, the image display is performed on one monitor, and the windows in the monitor are separately displayed. However, the enlarged display image of the subject width and the B image are output and displayed as separate image signals on a plurality of separate monitors. It is also possible to do so.
In this case, the number of display units required is equal to the number of monitors.

[0052]

As described above, according to the present invention, when calculating the ultrasonic probe movement vector for each frame image in the subject width enlargement function, the range of image data in the depth direction to be used is examined. Since it can be set in advance in accordance with the state of the unit, the reliability of the calculated and predicted ultrasound probe movement and estimation can be improved, and the error occurrence probability in image synthesis can be reduced.

In the subject width enlargement function, the image processing unit of the visual field enlargement processing unit generates the subject width enlarged display image and transfers the B image, so that the B image and the subject width enlarged display image are simultaneously displayed. That can be displayed,
Since the information such as the position between the probe and the subject is obtained by displaying the B image, there is an effect that the user can easily scan the probe.

[Brief description of the drawings]

FIG. 1 is a block diagram according to a first embodiment of the present invention;

FIG. 2 is a diagram showing a relationship between a block diagram and an image according to the first embodiment of the present invention;

FIG. 3 is a schematic view showing a function of displaying an enlarged display of a subject width in the first embodiment of the present invention;

FIG. 4 is a view showing an example of a user interface for setting an image range in the depth direction according to the first embodiment of the present invention;

FIG. 5 is a processing flowchart of an image processing unit according to the first embodiment of the present invention;

FIG. 6 is a diagram showing a relationship between a block and an image according to a third embodiment of the present invention;

FIG. 7 is a diagram showing a display example of a conventional enlarged display image of a subject width.

FIG. 8 is a diagram showing an example of simultaneous display of a B image and an enlarged display image of a subject width according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Scan converter part 2 Field-of-view expansion processing part 3 Display control part 4 Display part 21 B image Frame Buffer memory 22 Image processing part 23 Display memory 80 B image 81 Enlarged image of the test width generated by the field-of-view expansion processing part 82 Display control part Fig. 83 shows the relationship between the upper and lower limit values and the B image. 84 The latest B image and the image one frame before. 85 The enlarged test width image and the B image in the display control unit. 90 New frame image. Data acquisition processing 91 Effective data search processing 92 Probe movement amount estimation processing 93 Moving distance calculation processing 94 Image synthesis processing 95 Next effective image data range acquisition processing 221 CPU 222 Work memory 223 Upper limit memory 224 Lower limit memory

Claims (8)

[Claims] A scan converter unit for displaying a B image of an ultrasonic echo signal obtained from an ultrasonic probe, a subject width enlargement processing unit having an image display memory, a display control unit,
A display unit, and a memory in which a user sets and stores in advance an upper limit value and a lower limit value in a depth direction to be used when performing image processing for each ultrasonic probe moving distance, and the upper limit value and the lower limit value are set by the user. An ultrasonic diagnostic apparatus having a user interface set by the user. 2. A memory for storing upper and lower limit values of image data in the depth direction for each ultrasonic probe moving distance set in advance by a user, and a user setting according to a cumulative moving distance of the ultrasonic probe. 2. The apparatus according to claim 1, further comprising a subject width enlargement processing unit that performs ultrasonic probe movement prediction and estimation processing using image data within the effective image data range defined by the upper limit value and the lower limit value in the depth direction. Ultrasound diagnostic device. 3. A display apparatus according to claim 1, further comprising a user interface for allowing a user to perform a calculation for image processing again in the subject width enlarged display function, and to perform a recalculation without being restricted by a calculation processing time. An ultrasonic diagnostic apparatus as described in the above. 4. A field-of-view expansion processing unit comprising a scan converter for displaying an ultrasonic echo signal obtained from an ultrasonic probe in a B image, a field-of-view expansion processing unit having an image display memory, a display control unit, and a display unit. In the above, a plurality of B images are joined together and synthesized, and the enlarged B-display image and the B image are simultaneously transferred to the image display memory, so that the enlarged B-display image and the B image are simultaneously displayed in separate windows by the visual field enlargement function. Ultrasonic diagnostic equipment. 5. The ultrasonic diagnostic apparatus according to claim 4, wherein the B image is simultaneously displayed as separate images in separate windows on the same monitor together with the image obtained by combining the images by the visual field expansion function. 6. An upper limit value and a lower limit value of image data in a depth direction for each moving distance of an ultrasonic probe set in advance by a user in order to perform an enlarged display of a subject width. An ultrasonic probe that performs ultrasonic probe movement prediction and estimation processing using image data within the effective image data range defined by the upper limit and lower limit in the depth direction set by the user according to the total moving distance of the probe Movement estimation processing method. 7. The ultrasonic probe movement estimation processing method according to claim 6, wherein an input can be made to perform a calculation for image processing again by a user interface in order to perform the enlarged display of the subject width. Ultrasound diagnostic method. 8. A widened display of a subject width is performed in real time, a subject widened image is synthesized by image synthesis, and recalculation is performed without restriction on data processing time by using a plurality of obtained B image data. Ultrasound diagnostic method.