JPH04272750A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To offer the ultrasonic diagnostic device which can derive the generation frequency of luminance of a tomographic image in a body to be examined, and a flow velocity distribution image of a blood flow and can graph and display it, and also, can derive a parameter for evaluating a frequency distribution shape in each time phase, can show it as a numerical value or can graph and display it with regard to a desired period, respectively, and also, is applied to a difference image or a second order difference image. CONSTITUTION:Image data of a range designated by an area designating circuit 22 is transferred to an arithmetic memory 23, and subsequently, based on these image data, a frequency calculation for deriving a frequency of a determined order is executed. Next, based on this result, a graphic and numeral data are read out of a character generating circuit 24 and transferred to a graphic memory 25. This graphic memory 25 and a base image are added, and displayed on an indicator 9. This operation is executed successively onto a tomographic image as elapsed time.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to an ultrasonic diagnostic device.
In particular, in blood flow velocity distribution images whose image brightness changes over time, images of the circulatory system whose deviation occurs due to heart beats, etc., the brightness of ultrasound images from within a living body is generated within an arbitrary image range. This invention relates to an ultrasonic diagnostic device that can display frequency and distribution evaluation parameters and their changes over time.

0002

[Prior Art] An attempt was made to graph and display the frequency of occurrence of the brightness of ultrasound images and utilize it for diagnosis in Ultrasound Medicine (1986), Vol. 13, No. 6.
P. 19-27 Ultrasound Medicine (1988) Volume 15 No. 2
P. 42-46 Ultrasonic Medicine (1988) Volume 15 No. 2
P. It is described in papers such as 47-53. In these papers, mammary gland,
After setting a region of interest for the thyroid, liver, kidney, etc., the frequency of occurrence of brightness within that range is determined and normalized, then graphed and displayed. From this histogram, the shape of the distribution, average gradation value, Parameters such as standard deviation and mode are determined, and the relationship between these factors and diseases is discussed. Furthermore, in recent years, progress has been made in the development of technology for displaying the state of movement of organs by performing differential calculations between ultrasound images. (
(Refer to Japanese Unexamined Patent Publication No. 18054/1983)

0003

[Problem to be solved by the invention] Papers on ultrasound medicine are:
A region of interest is set in one static tomographic image, and the frequency of occurrence of brightness is determined within that range, and the frequency of occurrence of brightness is not determined and displayed over a plurality of images. Furthermore, the method described in the above-mentioned Japanese Patent Application Laid-open No. 189054/1989 performs one difference between tomographic image data and displays the image, and only one difference image is displayed. No consideration was given to measuring and displaying the frequency of occurrence of brightness.

[0004] A first object of the present invention is to provide an ultrasonic diagnostic apparatus that is capable of determining the frequency of occurrence of brightness in a tomographic image within a subject and a flow velocity distribution image of blood flow over a desired period of time, and displaying it in a graph. It is to be.

A second object of the present invention is to have a function of selecting a plurality of variables from the three variables of frequency, brightness, and time and displaying them in a graph, and a means for displaying these graphs and an ultrasound image. An object of the present invention is to provide an ultrasonic diagnostic apparatus equipped with the above-mentioned ultrasonic diagnostic equipment.

A third object of the present invention is to develop parameters for evaluating the shape of the frequency distribution, such as the mode, maximum value, minimum value, average value, half-value width, minimum value-maximum value width, and standard deviation of the frequency distribution of luminance. An object of the present invention is to provide an ultrasonic diagnostic apparatus capable of determining and displaying the values in numerical values or graphs for each time phase for a desired period.

A fourth object of the present invention is to obtain the frequency of occurrence of luminance within a specified image range in a differential image or a second-order differential image, and calculate the frequency of occurrence of luminance, the mode, maximum value, minimum value, average value, half-width, An object of the present invention is to provide an ultrasonic diagnostic apparatus that can display parameters for evaluating the frequency distribution shape, such as the minimum value-maximum value width and standard deviation, in the form of numerical values or graphs.

[0008]

[Means for Solving the Problems] In order to achieve the above-mentioned first object, the present invention provides data in a graphic memory that stores a graph of the frequency of occurrence of luminance within a specified range and the time phase thereof. The apparatus is provided with means for adding image data, storage means for temporarily storing the result, and means for rewriting the data into the image memory.

[0009] In order to achieve the above second objective, the first
In addition to the means for achieving the above purpose, a brightness specifying means and a frequency specifying means are provided, and furthermore, a means for reading and storing the frequency (degrees) of the specified brightness, and a means for reading and storing the brightness of the specified degree are provided. It is something that

[0010] In order to achieve the above third objective, the second
Instead of a calculation method within the means to achieve the purpose of, the mode,
It calculates the average value, standard deviation, etc., and adds a storage means to save the results.

[0011] In order to achieve the fourth object, a supercomputer is provided with a difference processing means and a function of graphing and displaying the frequency of occurrence of luminance in a specified range of images subjected to the difference processing. The sonic diagnostic device is equipped with a storage means for calculating the mode, average value, standard deviation, etc., and storing the results.

0012

In the ultrasonic diagnostic apparatus according to the first aspect, the means for specifying an arbitrary image range is such that the user specifies a desired area using, for example, a trackball and a marker displayed on the screen. Next, upon receiving this area information, the controller controls the memory control means to read image data within the area from the image memory into the calculation memory. Furthermore, the controller counts up the brightness frequency based on these image data. As a result, the brightness and its frequency can be determined. Next, a desired character is selected based on the brightness and frequency and written into the graphic memory. Then, the graphic memory data and the tomographic image data or the blood flow velocity distribution image are added and temporarily stored, and then rewritten to the image memory. By repeating this process, the brightness frequency distribution in any range of the image can be determined for a period of one heartbeat or more at each time phase, so it is possible to quantitatively understand how the brightness frequency distribution changes over a long period of time.

[0013] In the ultrasonic diagnostic apparatus according to the second aspect, the frequency of occurrence of brightness is determined in the tomographic image of each time phase, and then a plurality of variables are selected from among the three variables of desired brightness, frequency, and time and graphed. indicate. This makes it possible to quantitatively understand the relationship between time, brightness, and frequency in areas where the brightness distribution changes over time, such as in liver hemangioma or intravascular blood flow images.

In the ultrasonic diagnostic apparatus according to the third aspect of the present invention, various parameters for evaluating the frequency distribution shape are obtained from the tomographic image of each time phase, and the graph is written in a graphic memory. The graphic memory data is then written into a memory that stores tomographic images or blood flow velocity distribution images using parameters. Next, the image to which the parameters have been added is displayed. As a result, it is possible to quantitatively understand changes in the distribution shape at a portion where the luminance frequency distribution changes over time during a desired period.

In the ultrasonic diagnostic apparatus according to the fourth aspect of the present invention, parameters for evaluating the shape of the frequency distribution of brightness within the image range specified by the differential image are determined, and then the desired parameters are graphed and displayed. Thereby, it is possible to quantitatively understand the deviation of a moving part within a certain region and its change.

[0016]

Embodiments Hereinafter, embodiments of the present invention will be explained with reference to FIGS. 1 to 9.

Embodiment 1 FIG. 1 shows a block diagram of a first embodiment of the present invention. In the figure, 1 is a probe that sends and receives ultrasonic waves into the living body, and 2 is a switch that converts the ultrasonic waves into a transmitting signal and an electric signal to be sent to the ultrasonic generating element in the probe. 3 is a transmitting signal generator that outputs a transmitting signal to generate ultrasound of a desired frequency and wave number; 4 is a receiving signal processor In a vessel,
5 is a digital scan converter (hereinafter referred to as DSC) that performs amplification, phasing, addition, compression, detection, etc. of each received signal.
It is written as ) has a built-in A/D converter and converts the received signal, which was an analog signal, into a digital signal.Then, the received signal is temporarily stored for each ultrasonic scanning line in multiple line memories, and is converted every time transmission and reception are repeated. Then, the stored line data is output to an image memory, and a tomographic image, which is a two-dimensional image, is created from the data for each ultrasonic scanning line within the image memory.

Further, the DSC 5 includes a known circuit for detecting Doppler deviation from data for each scanning line and detecting a blood flow image. Reference numeral 6 denotes an image memory, which has a storage capacity capable of storing a plurality of ultrasonic tomographic images, and sequentially reads the image data output from the DSC 5. Reference numeral 7 denotes a plurality of line memories, which sequentially read the received display image data. 8 is a D/A converter that converts display image data into an analog signal for TV, 9 is a display device, for example, a TV monitor. 10 is an external image storage device for displaying an image, such as a digital VTR. This external image storage device 10 may be a disk, tape, or the like that stores data using light or magnetism, as long as the writing and reading speeds allow. Reference numeral 11 denotes a known image stop circuit consisting of switches and the like. 12 is the controller,
Controls each circuit, calculates the frequency of image brightness, and controls character selection based on the results.

13 is an address generation circuit for each image memory,
14 is an RW (read/write) control circuit that selects which memory to access;
It also controls whether it is a write state or a read state. 20 is a switch that selects one signal line among the DSC 5, image memory 27, and external image storage device 10 and connects it to the image memory 6; 21 is a switch that connects the output from the image memory 6 to the line memory; Output to 7 or adder 2
Reference numeral 22 is an area designation circuit for selecting whether to output to 6, and 22 is an area designation circuit, for example, a trackball. 23 is an arithmetic memory that stores image data and calculation results necessary for calculating the frequency of occurrence of brightness within the controller 12; 24 is a character generation circuit that stores numbers and figures necessary for graphing in ROM; 25 which stores character data and outputs character data according to instructions from the controller 12;
is a graphic memory which has a storage capacity equivalent to a TV screen, stores graphic data, and can be rewritten as necessary; 26 is an adder which adds the data in the image memory 6 and the graphic memory 25; 27 is an image memory, which includes an image memory 6 and a graphic memory 25.
The result of adding the two types of memory data is temporarily stored.

Next, the operation of the first embodiment will be explained. The transmission signal generator 3 generates a transmission signal by setting a time difference between a plurality of vibrating elements so as to converge an ultrasound beam on a designated site within a living body. Next, the switch 2 switches the signal path according to a signal sent from the controller 12 to determine whether the wave is in a transmitting state or a receiving state. If it is in the transmitting state, the transmitting signal is sent to the probe 1 . In the probe 1, a transmission signal, which is an electric signal, is converted into an ultrasonic wave by a vibrating element, and the ultrasonic wave is transmitted to a living body. The ultrasonic waves are reflected at boundaries with different acoustic impedances in the living body and are received by the probe 1 . In the probe 1, the ultrasonic wave is converted into an electric signal in the opposite manner to the time of transmission, and the received signal is sent to the reception signal processor 4 with the switch 2 switched to the reception signal path. Sent. The received wave signal processor 4 performs amplification, phasing, addition, compression, detection, etc., and combines the received signals of the plurality of transducer elements into one received signal. Next, the received signal is sent to the DSC5,
The analog signal is converted into a digital signal by an A/D converter and written into the first line memory. The above operations constitute image data of the first ultrasonic scanning line.

Next, inside the DSC 5, the image data of this first ultrasonic scanning line is read out from the first line memory and written into the built-in image memory. During this time, the same wave transmission and reception as described above is performed while changing the scanning direction, and the image data of the second ultrasonic scanning line is written into the second line memory. At this time, the switch 20 selects the signal path of the DSC 5 by the controller 12. Third
While transmitting and receiving waves for the ultrasonic scanning line of
Within the SC5, data is read from the second line memory and written to the image memory within the DSC5, and at the same time, image data of the third ultrasound scanning line is written to the first line memory. The above operations are repeated in sequence to construct a first ultrasonic tomographic image in the image memory of the DSC 5. When the first ultrasonic tomographic image is constructed, the controller 12 initializes the ultrasonic scanning line direction, and repeats the wave transmission and reception in sequence according to the procedure described above to construct a second ultrasonic tomographic image. do. During this time, the RW control circuit 14 controls the selection of each memory mentioned above and whether the memory is in a read state or a write state. Further, the address generation circuit 13 generates read or write addresses for each memory according to the control state of the RW control circuit 14.

The ultrasonic tomographic images obtained in this way are stored in the image memory 6 one after another because the switch 20 selects the signal path of the DSC 5 using the controller 12. Next, in response to instructions from the controller 12, the address generation circuit 13 and the RW control circuit 14 operate so that tomographic images are sequentially read out from the image memory 6 starting from the first ultrasonic tomographic image. The switch 21 switches the controller 1 so that the tomographic image data from the image memory 6 is sent to the line memory 7.
The signal path is switched according to the instruction 2. Therefore, the tomographic image data is written in the line memory 7 and read out in synchronization with the TV synchronization signal in units of TV scanning lines. and,
After being converted into a TV analog signal by the D/A converter 8,
It is displayed on the TV monitor of the display device 9. Furthermore, if the observation time of the tomographic image is long, the external image storage device 10 may be used by controlling the switch 20. The external image storage device 10 is, for example, a digital VTR, and sequentially writes image data transferred from the line memory 7 in synchronization with the TV. In the present invention, the image data stored in the external storage device 10 is transferred to the image memory 6 again when determining the frequency of occurrence of brightness. A method for calculating the frequency of occurrence of brightness will be described later.

On the other hand, when constructing a flow velocity distribution image of blood flow, the output of the receiving signal processor 4 is multiplied by a sine wave of a specific frequency, and then sample-holded, A/D converted, and velocity calculations are performed. Use this method. The blood flow velocity distribution image obtained by this method is stored in the image memory built into the DSC 5 and displayed using the same display method as described above. next,
A means for determining the frequency of occurrence of brightness in a specified range within an image and displaying it in a graph will be explained. It consists of three means. First, the area specifying means will be explained. The area specifying circuit 22 in FIG. 1 is composed of, for example, a trackball or a joystick. The user can view images drawn in real time on the screen of the display 9 or the external storage device 10.
The user observes the reproduced image of the data stored in the , and stops the image when the required screen is displayed using an image stop circuit 11 consisting of a switch and the like. (Hereinafter, this still image will be referred to as a reference image.) Next, a marker is displayed on this still screen by a known marker generation circuit, and this marker is moved on the screen using a trackball or the like of the area specifying circuit 22. Move it to enclose the required area. The marker position information is obtained by converting the displacement of a mechanical system such as a trackball into an electrical signal using an encoder.
It is sent to the controller 12.

Next, a method for calculating the luminance frequency will be explained using FIGS. 2 and 3. As a display example, a tumor-like lesion such as a hepatic hemangioma is shown in FIG. 2(a). Assume that the range is determined by the above-mentioned area specifying means as shown in FIG. 2(b). The display screen is shown in Figure 2(c) for clarity of explanation.
As shown in , the lower left end of the ultrasonic scanning line is 0, the horizontal direction is the x axis, the vertical direction is the y axis, the right end of the x axis is (X, 0), and the upper end of the y axis is (0, Y). In addition, the designated area can have any shape, but for the sake of simplicity, (xmin, y
The area is a rectangular area in which two points, min) and (xmax, ymax), are opposed to each other. FIG. 2(d) shows a storage area for one screen in the image memory 6. Ultrasonic image data is written into the image memory 6 according to the ultrasound scanning line direction (0, Y).
Suppose that it starts from , and is written in the y direction. Figure 2(d)
Inside, the ultrasonic scanning line is indicated as L(i), and the pixels of the ultrasonic scanning line are indicated as pix(i). Then, the ultrasonic scanning lines are L(0), L(1), L(2),...,L(Xmin
), ..., L(Xmax), ..., L(X). In addition, reading is performed at pix(Y
), pix of L(1) (Y), ..., pix of L(X) (
Y), pix of L(0) (Y-1), pix of L(1)
(Y-1),...,L(X) pix(Y-1),...,L
It is read out to be pix(0) of (X).

The controller 12 controls the address generation circuit 1 so that writing and reading are performed in this order.
3. Controls the RW control circuit 14 and receives data. Inside the controller 12, a memory address within the area is calculated from the position information when specifying the area, and when this value matches the value of the address generation circuit 14, the image data is stored in the calculation memory 23. The frequency of the image data read into the calculation memory 23 in this manner is calculated according to the calculation procedure shown in FIG. Figure 3 shows the calculation flow for frequency calculation. As mentioned above, controller 1
The image data loaded in 2 is sequentially transferred from US (1) to U.
Let it be S(n). Next, to find the frequency distribution of brightness,
Set class J. Here, class J is luminance. In this embodiment, the luminance is set to k gradations from 1 to k, and the number of classes is k.
It will be explained as follows. J is first initialized as 1. Next, the image data US(1) is read from the calculation memory 23, and it is determined whether J and US(1) are equal. If the numbers are different, count up J by 1 and judge again. By the time J is counted up to the number k, J=US(
1) When the following relationship is established, count up the frequency F(J) of class J by one. . This operation is changed from US(1) to U
Perform the calculation for all the numbers up to S(n) and store the results in the calculation memory 2.
After writing to the other storage area of 3, the process ends.

Next, the graph display will be explained. The character generation circuit 24 is a ROM that stores graphical element data necessary for displaying lines, scales, numbers, and distributions that constitute the vertical and horizontal axes, or line segments, etc. necessary for graphing. It consists of a graphic controller that generates graphic data such as circles. In order to display a graph at a predetermined graph display position, the controller 12 first creates an address in the ROM so as to read out the necessary data of the vertical axis, horizontal axis, scale, and numbers from the character generation circuit 24, or Send the necessary data to the controller. As a result, the graphic data obtained in dot units is transferred to the graphic memory 25. At the time of transfer, since the graphic memory 25 has a storage area for TV screen images, it is controlled by the address generation circuit 13 to generate a graphic memory address corresponding to the display position. Next, the controller 12 calculates the display coordinates for displaying the graph from the graph display position and the frequency F(J) of each class, and stores it in the graphic memory 25 in dot units using the same method as for displaying the graph axes described above. Write the obtained graphic data.

Next, a method for displaying a luminance occurrence frequency graph in a certain desired period will be described. After the above-described operation, the image memory 6 again operates the address generation circuit 13.
, the readout is controlled by the RW control circuit 14, and the image that is the target of the frequency of occurrence calculation is read out again. At this time,
The switch 21 is controlled by the controller 12 so that the signal path is on the adder 26 side. The adder 26 adds the image for which the frequency of occurrence has been calculated and the graphic data of the luminance frequency distribution graph that has already been written in the graphic memory 25 at this time. This added image data is temporarily stored in the image memory 27. Next, data is read from the image memory 27, and at this time,
A switch 20 switches the signal path to an image memory 27. The image memory 6 is under write control and updates the area of the image that is the target of the frequency of occurrence calculation. In other words, a frequency distribution graph of brightness is written in the image data in the image area that is the target of the frequency of occurrence calculation in the image memory 6.

By sequentially performing this operation on all images written in the image memory 7, such as from the reference image to the image of the next time phase, all tomographic images over a certain desired period, for example, one heartbeat or more, can be A frequency distribution graph of brightness can be obtained from the image. For example, when the controller 12 continuously reproduces the reference image to the image of the next time phase, the luminance occurrence frequency graph is always displayed during that period. An example of the display is shown in FIG. FIG. 4 shows times t1, t2, t3
Figure 4 shows the result at time t1.
(a), the one at t2 is shown in FIG. 4(b), and the one at t3 is shown in FIG. 4(c). On the display screen, a tomographic image is displayed above, the area specified by the area specifying means within the tomographic image is displayed, for example, with a broken line, and the brightness within the specified area is displayed below the tomographic image. The frequency of occurrence is displayed in a graph (histogram display).

The histogram displays luminance on the horizontal axis and frequency of occurrence on the vertical axis. Referring to Figure 4,
It can be seen that as time passes from time t1 to time t2 to t3, a graph is displayed in which a portion with high brightness gradually decreases and a portion with low brightness gradually increases. When the brightness gradation of a tomographic image is displayed in very fine gradations, such as 256 gradations, it is extremely difficult to visually detect slight gradation changes. This is easily possible if you do this. Furthermore, if the observation period extends for a long time, the images are temporarily stored in the external image storage device 10 as described above. Next, when carrying out the present invention, the image data is transferred to the image memory 6 as many images as can be stored, and the above-described operations are performed. Then, the switch 21 is switched to the line memory 7, and the image in which the frequency distribution graph of brightness is written in the image data is stored in the external image storage device 10. This operation is repeated for all images stored in the external image storage device 10. When reproducing this image, a separate display may be provided in the external image storage device 10, and a switch may be provided between the D/A converter 8 and the line memory 7 and the output path of the external storage device 10 may be connected to the switch and displayed on the display 10 by, for example, being switched by the user.

Furthermore, in this embodiment, the switching device 21 is switched by a series of operations for calculating the frequency of occurrence. Depending on the state of this switching, the display changes to a different image or is not displayed during the calculation period. To avoid this,
An image memory may be further provided between the switch 21 and the line memory 7, and images stored in the image memory may be displayed.

Note that although an example in which normalization is not performed was used in calculating the frequency of occurrence of brightness, normalization does not impair the effects of the present invention. Further, although a linear scanning tomographic image is shown as an example of a tomographic image, images obtained by other tomographic scanning means, such as sectors and convex images, may also be used. By storing the blood flow distribution image in the image memory 6, the present invention can be applied to the blood flow velocity distribution image. Furthermore, in the description of the present invention, the region designation is performed once at the beginning, but it may be performed for each tomographic image at each time. Further, although the explanation is given as one area in one image, multiple areas may be specified and multiple graphs may be displayed.

[0031]

[Embodiment 2] FIG. 5(a) shows a block diagram of a second embodiment of the present invention. This is obtained by replacing the controller 12 in FIG. 1 with a controller 33 shown in FIG. 5(a), and adding circuits shown by numerals 30 to 36. Reference numeral 30 denotes a graph selection circuit, which includes a panel switch and the like for selecting the display method shown in the display examples shown in FIGS. 5(b) and 5(c). Reference numeral 31 denotes a brightness designation circuit, which includes a panel switch and the like for setting a desired brightness when the display method shown in FIG. 5(b) is selected. Reference numeral 32 denotes a frequency designation circuit, which includes a panel switch and the like for setting a desired frequency when the display method shown in FIG. 5(c) is selected. A controller 33 performs calculations, controls each circuit, and reads signals from each circuit including panel switches and the like. A frequency memory 34 stores the calculation result when the display method shown in FIG. 5(b) is selected. 35 is the brightness memory,
The calculation result when the display method shown in FIG. 5(c) is selected is stored. Reference numeral 36 denotes a scanning condition setting circuit comprising a panel switch and the like for specifying the known scanning range, depth, number of transmission focus stages, etc.

Next, the operation of the second embodiment will be explained. The operations from the probe 1 to the display 9 and the external image storage device 10 are similar to those in the first embodiment. In this embodiment, as in the first embodiment, there are three types of means: an area specifying means, a calculation means provided in the controller 33, and a graphing means. Of these, the area specifying means and the display means are similar to those in the first embodiment, and the calculation results of the frequency calculation means shown in the first embodiment are stored in the calculation memory 23. The calculation means of this embodiment will be explained below.

First, the case where a graph is created and displayed using the display method shown in FIG. 5(b) will be explained. Display method diagram 5 (b
), the horizontal axis is the time elapsed from an arbitrary tomographic image as a reference, and the vertical axis is the frequency of occurrence of brightness (frequency) determined by the brightness designation circuit 31. When obtaining a tomographic image by ultrasonic scanning, the known scanning condition setting circuit 36 has already set the
The ultrasonic scanning range, the number of transmission focus stages, the depth, etc. are determined by the user. This determines the frame rate, that is, the time interval of tomographic images captured in time series. Thereafter, the time is determined by determining the number of images from the reference image in the image memory 6 from the address and calculating the product with the above-mentioned time interval.

Next, the vertical axis will be explained. In the brightness designation circuit 31, a desired brightness K is designated by the user. The designated brightness K is read into the controller 33 and is shown in FIG. 6(a).
) The calculation process is performed according to the flow shown in (). That is, after the specified brightness K is read, the tomographic image to be calculated is set as the i-th tomographic image and the variable i is initialized. In the calculation memory 23,
The occurrence frequency calculation results are stored for each image of each time phase. First, to read the frequency F(K) of the first tomographic image, the controller 33 controls the address generation circuit 14 based on the variables i and K, obtains a read address, and accesses the calculation memory 23. Next, the frequency F(K) is set as a variable H
Substitute in (i). Then, for all tomographic images, the degree F(
The variable i is counted up until K) is read. When the assignment is completed for all H(i), the result is written into the frequency memory 34. When the data on the vertical and horizontal axes are obtained by the above method, they are graphed and displayed on the display 10 using a method similar to the display method shown in the first embodiment. Further, the designated brightness K read into the controller 33 at this time may be displayed.

Next, the display method shown in FIG. 5(c) will be explained. The horizontal axis is determined by the method described above. The vertical axis is determined by the calculation method shown in FIG. 6(b). In the frequency designation circuit 32, a desired frequency H is designated by the user. The designated frequency H is read into the controller 33 and shown in FIG.
) is performed. That is, after the designated frequency H is read, the tomographic image to be calculated is set as the i-th tomographic image, and variables i, j, and k are initialized. First, the frequency F(j) of the first tomographic image is read from the calculation memory 23 from j=1, and when the relationship H=F(j) holds, the value is set to the variable K(i, j). substitute. From now on, when H≠F(j),
j is counted up by 1 and the above calculation is performed for all frequency data of the i-th tomographic image. On the other hand, the number of images stored in the image memory is determined by storage capacity and other factors. Let the number of images in the image memory 6 be m. When the i-th tomographic image is completed, the same process is performed for the (i+1)-th tomographic image until i=m, that is, until all tomographic images in the image memory 6 are processed.

In this way, all K(i, j) are obtained and the results are written into the brightness memory 35. When the data on the vertical and horizontal axes are obtained by the above method, they are graphed and displayed on the display 9 using the same method as the display method shown in the first embodiment. Further, the designated frequency H read into the controller 33 at this time may be displayed. Furthermore, since there are three variables: brightness, frequency, and time, it may be displayed as a three-dimensional graph using a known three-dimensional graphing method.

[0037] This allows the desired frequency of brightness to be observed over time. Conversely, it is possible to set a desired frequency and observe its brightness over time. Thereby, for example, it is possible to quantitatively observe changes in brightness over time for a lesion, such as a hepatic hemangioma, whose brightness changes over time. Note that, as described in the first embodiment, even if each graph is normalized, the effects of the present invention are not impaired. Also,
By storing a blood flow distribution image obtained by a known blood flow distribution image forming means in the image memory 7, the present invention can be applied to a blood flow velocity distribution image. Furthermore, although the explanation is given as one area in one image, multiple areas may be specified and multiple graphs may be displayed.

[0038]

[Embodiment 3] A third embodiment of the present invention will be described with reference to FIGS. 7 and 8. The hardware of this embodiment is almost the same as that of the second embodiment, except that the frequency memory 34 and brightness memory 35 for storing calculation results are replaced with memories for storing parameter calculation results. The parameters referred to here are evaluation parameters used to evaluate the frequency of occurrence of brightness, an example of which is shown in FIG.

In the present invention, these parameters are calculated and graphed from the frequency of occurrence of brightness in each image stored in the image memory 6, and thereafter, the graphic memory data is stored in the image memory using the same procedure as in Example 1. This is in addition to 6. Examples of the display are shown in FIGS. 8(a) to 8(c). For example, in (a), the mode is graphed with time on the horizontal axis and brightness on the vertical axis, and if necessary, the time in the displayed image,
Parameters such as average values can also be displayed. Next, the calculation procedure will be explained using FIG. 8. First, variable i is initialized. Next, the brightness frequency distribution data in the first tomographic image is read from the image memory 6 into the controller 33 from the arithmetic memory 23 . Next, parameter values are calculated using a calculation program that calculates the various parameters described above. Then, the variable i is counted up until the frequency distribution data of all images stored in the calculation memory 23 is completed. When the process is completed for all images, the parameter calculation results are transferred to the memory for storing the calculation results and the process ends.

[0040] Once the vertical axis data has been obtained for all images using the above method, the horizontal axis (time axis) calculation method, graphing method, and image memory 6 shown in Example 1 and Example 2 are then applied.
It works the same way as writing to . Then, it is displayed on the display 9 at a desired time. As described above, the various parameters used for evaluating the distribution shape can be graphed and stored in the image memory 6, so that the graph can be displayed immediately together with the tomographic image upon reading, and changes in the various parameters can be observed over a long period of time. Thereby, for example, it is possible to observe changes in various parameters over time and quantitatively for a lesion whose brightness changes over time, such as a liver hemangioma. Note that, as described in the first embodiment, even if each graph is normalized, the effects of the present invention are not impaired. Further, a blood flow distribution image obtained by a known blood flow distribution image forming means is stored in the image memory 7.
The present invention can be applied to a blood flow velocity distribution image by storing . Furthermore, although the explanation is given as one area in one image, multiple areas may be specified and multiple graphs may be displayed.

[0041]

Embodiment 4 FIG. 9 shows a block diagram of a fourth embodiment of the present invention. In this example, a part of the configuration in Example 1 is changed to the illustrated circuit. In Figure 9, 4
0 is an image memory, which has a storage capacity capable of storing tomographic images of one heartbeat or more. 41 is a difference processor and image memory 4
The difference between two images within 0 is performed so that the respective pixels correspond to each other, and the difference processing is performed once or twice. 42 is a switch that selects one of the signal paths of the difference processor 41, the external image storage device 11, and the image memory 27;
Connect to the signal path. Reference numeral 43 denotes an image memory, which has a storage capacity capable of storing images obtained by subtracting ultrasound tomographic images once or twice (hereinafter referred to as difference images or second-order difference images) over a period of one heartbeat or more. have A switch 44 selects one of the signal paths of the image memory 40 and the image memory 43 and connects it to the signal path of the controller 47. 45
is a switch which selects one of the signal paths of the image memory 40 and the image memory 43 and connects it to the signal path of the switch 46. A switch 46 selects and switches the signal path from the image memory 45 to one of the signal paths of the adder 46 and the line memory 8.

Next, the operation of the fourth embodiment will be explained. Although the present invention is applied to tomographic images in Examples 1 to 3, it can also be applied to difference images and second-order difference images. Therefore, each circuit not shown in FIG. It is the same as that shown in 3 and also operates in the same way. First, a user selects a desired image from among a tomographic image, a difference image, and a second-order difference image using the image selection means 40. Next, Example 1
The tomographic image is written into the image memory 40 using the same operation as shown in FIG. Next, the tomographic image is read out from the image memory 40. At this time, the switch 45 switches the image memory 40 to the switch 4.
6 selects line memory 8. Thereafter, the information is displayed on the display 10 in the same manner as in the first embodiment. On the other hand, the difference processor 41
performs a difference so that the pixels of the two images correspond. The n-th tomographic image captured in the image memory 40 and the n+m-th (
m is an integer of 1 or more). Further, when performing the difference twice, the difference processor 41 has a memory capable of storing at least two images, and stores the two images resulting from the first difference. Then, the differential image data are read out from this memory, and the pixels are made to correspond again to perform differential processing. The difference image or second-order difference image thus obtained is transferred to the image memory 43 with the switch 42 selecting the difference processor 41 as the signal path.

Next, area designation is performed using the method shown in the first embodiment. Next, the switch 44 switches the signal path to the image memory 43 side according to instructions from the controller 47. Then, similarly to the method shown in the first embodiment, the difference image or the second-order difference image is transferred to the controller 47, and the frequency of occurrence of brightness is calculated. Thereafter, graphing is performed and output to the adder 26. At this time, the switch 45 selects the signal path to the image memory 43 side, and the switch 46 selects the signal path to the adder 26 side. . Then, the image data is read out from the image memory 43 again and added to the graph data by the adder 26. After being temporarily stored in the image memory 27, the switch 42 selects the signal path of the image memory 27, and the data is written to the image memory 43. When displaying, the switch 46 selects the line memory 8 side and the display 10 displays it. When the external storage device 11 stores a difference image or a second-order difference image, the switch 42 selects the signal path to the external storage device 11 side. Thereafter, the frequency of occurrence of brightness is graphed and displayed using the same method as in the first embodiment. In addition, by newly providing an adder and a color encoder on the input side of the switch 46, a superimposed image of a tomographic image and a difference image or a second-order difference image can be created.
This embodiment can also be applied to the case of display. The techniques of the second and third embodiments can be applied with the same operation as this one.

As described above, it is possible to observe the frequency of occurrence of brightness in a difference image or a second-order difference image over a period of one heartbeat or longer. The difference image and the second-order difference image reflect velocity information and acceleration information of the moving part, respectively, and their brightness reflects the magnitude of the velocity and acceleration. Therefore, for example, if a lesion causes stiffness in a region that moves with heartbeat, such as the vascular system, and the state of movement changes, the graph of the frequency of occurrence of brightness changes the distribution shape. Graphically displaying the frequency of occurrence of the brightness of these images provides an objective evaluation in which this information is grasped as numerical values from the subjective evaluation of the images, and furthermore, changes over time can also be observed. In addition, it is possible to determine the frequency of occurrence of a desired brightness in a difference image or a second-order difference image, or conversely, to observe the brightness over time, and it is possible to evaluate changes over time in specific speeds and accelerations. In addition, since the various parameters used to evaluate the distribution shape are graphed and stored in the image memory 40, the graph can be displayed immediately along with the difference image or second-order difference image upon reading out, and the graph can be displayed over a long period of time. Changes are observable.

In the description of this embodiment, the region specification is performed once at the beginning, but it may be performed for each tomographic image at each time. Further, although the explanation is given as one area in one image, multiple areas may be specified and multiple graphs may be displayed. Note that, as described in the first embodiment, even if each graph is normalized, the effects of the present invention are not impaired.

[0046]

According to the present invention, as explained above, the following excellent effects are brought about. That is, in claim 1, the frequency of occurrence of brightness in a tomographic image can be graphed and observed over time. For example, even in a lesion where the brightness changes over time, such as a liver hemangioma, the change in brightness over time can be understood as a numerical value and objectively evaluated. In the second aspect of the present invention, in a lesion where the brightness changes over time, such as a hepatic hemangioma, specific brightness and frequency are focused on and displayed graphically, so that changes over time can be observed in detail. In the third aspect, the parameters for evaluating the distribution shape are obtained and stored in the image memory, so that they can be displayed immediately when desired, and their changes over time can be observed. In claim 4, it becomes possible to observe the frequency of occurrence of brightness in the difference image or the second-order difference image over a period of one heartbeat or more. For example, if the state of motion changes in a region that moves with heartbeat, such as the vascular system, the graph of the frequency of occurrence of brightness will change the distribution shape, but it is not possible to display the frequency of occurrence of brightness in these images graphically. This information is objectively evaluated as numerical values based on subjective evaluations of images, and changes over time can also be observed. In addition, because the difference image or second-order difference image focuses on specific brightness and frequency and displays it graphically, changes over time can be observed in detail.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of read and write operations of the image memory 7 shown in FIG. 1;

FIG. 3 is a diagram showing a brightness frequency calculation flow within the controller of FIG. 1;

FIG. 4 is a diagram showing a display example of the first embodiment of the present invention.

FIG. 5 is a diagram showing a second embodiment of the present invention and a display example thereof.

FIG. 6 is a diagram illustrating a calculation flow in a second embodiment of the present invention.

FIG. 7 is a diagram illustrating evaluation parameters determined in a third embodiment of the present invention.

FIG. 8 is a diagram showing a display example and a calculation flow in a third embodiment of the present invention.

FIG. 9 is a block diagram showing a fourth embodiment of the present invention.

[Explanation of symbols]

1 Probe 2 Switch 3 Transmission signal generator 4 Reception signal processor 5 Digital scan converter 6 Image memory 7 Line memory 8 D/A converter 9 Display 10 External image storage device 11 Image stop circuit 12 Controller 13 Address generation circuit 14 RW control circuit 20 Switch 21 Switch 22 Area specification circuit 23 Arithmetic memory 24 Character generation circuit 25 Graphic memory 26 Adder 27 Image memory 30 Graph selection circuit 31 Brightness specification circuit 32 Frequency specification circuit 33 Controller 34 Frequency Memory 35 Brightness memory 36 Scanning condition setting circuit 40 Image memory 41 Difference processor 42 Switch 43 Image memory 44 Switch 45 Switch 46 Switch 47 Controller

Claims (4)

[Claims] Claim 1: A probe having a plurality of vibrations that transmits ultrasonic waves into a living body and receives reflected waves from tissues with different acoustic impedances within the living body;
A transmitting signal generating means for vibrating at a wave number, a receiving signal processing means for amplifying, phasing, adding, compressing, detecting, etc. each receiving signal from the probe, and an output of the receiving signal processing means. A/D converter that constructs tomographic images based on signals, line memory,
In an ultrasonic diagnostic apparatus equipped with a digital scan converter including an image memory, means for storing a plurality of tomographic images within a predetermined period, and means for reading and displaying these images in chronological order, each image is means for specifying an arbitrary image range, a calculation means for sequentially calculating for each image the frequency of occurrence of the luminance of the image signal within the range specified by the image range specification means, and a calculation result of the calculation means. What is claimed is: 1. An ultrasonic diagnostic apparatus comprising: means for sequentially graphing the data; and display means for displaying the output of the graphing means. 2. The ultrasonic diagnostic apparatus according to claim 1,
An ultrasonic diagnostic apparatus characterized in that by selecting a plurality of variables from among three variables, frequency of occurrence, brightness, and time, and displaying them in a graph, these graphs and ultrasonic images can be observed during a desired period. 3. The ultrasonic diagnostic apparatus according to claim 1 or 2, wherein the mode, maximum value, minimum value, average value, half-width, An ultrasonic diagnostic apparatus characterized in that parameters for evaluating the shape of a frequency distribution such as the minimum value-maximum value width and standard deviation are expressed numerically or graphically, and the ultrasonic images and these parameters can be observed during a desired period. 4. A probe having a plurality of transducers for transmitting ultrasonic waves into a living body and receiving reflected waves from tissues with different acoustic impedances within the living body; , a transmitting signal generating means for vibrating at a wave number, a receiving signal processing means for amplifying, phasing, adding, compressing, detecting, etc. each receiving signal of the probe, and an output of the receiving signal processing means. A digital scan converter that includes an A/D converter, line memory, and image memory that constructs tomographic images based on signals, a difference processor that performs difference processing between images, and the output data of this difference processor is displayed as an image. In the ultrasonic diagnostic apparatus, the ultrasonic diagnostic apparatus includes a means for specifying an arbitrary range on the image subjected to the difference, and a means for specifying the frequency of occurrence of luminance within the image range specified by the image range specifying means for each difference. An ultrasonic diagnostic apparatus comprising means for sequentially performing calculations on images, means for sequentially graphing the calculation results of the calculation means, and means for displaying the output of the graphing means.