JPH10137241A - Ultrasonic diagnostic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To plot out a tomographic image or a blood stream image through interpolation based on the form of ultrasonic beams without using an ideal function such as linear function or sampling function for interpolating between adjacent rasters or adjacent sample points inside one raster. SOLUTION: A beam pattern memory 8 for preserving and outputting twodimensional beam pattern data such as azimuth and depth direction required for interpolating tomographic image data from a raster memory 10 is connected to an interpolation computer 12 inside a DSC 5 and while using the two-dimensional beam pattern data from the beam pattern memory 8 under the control of a controller 15 inside the DSC 5, data interpolating operation is performed by the interpolation computer 12. Thus, the tomographic image or blood stream image can be plotted out by performing the interpolation based on the form of ultrasonic beams without using any ideal function such as linear function or sampling function for interpolating the gap between adjacent rasters or adjacent sample points inside one raster.

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 for obtaining and displaying a tomographic image or a blood flow image of a diagnostic site in a subject using ultrasonic waves, and more particularly to an ultrasonic diagnostic apparatus between adjacent rasters or within one raster. Ultrasound that can draw tomographic images and blood flow images by performing interpolation according to the ultrasonic beam shape without using ideal functions such as linear functions and sampling functions to interpolate between adjacent sample points The present invention relates to an ultrasonic diagnostic apparatus.

[0002]

2. Description of the Related Art A conventional ultrasonic diagnostic apparatus of this type includes a probe for transmitting / receiving an ultrasonic wave to / from a subject, transmitting the ultrasonic wave by driving the probe, and receiving a reflected echo signal. Ultrasound transmitting / receiving unit to be processed, tomographic scanning means for repeatedly obtaining tomographic image data in a subject including a moving tissue using a reflected echo signal from the ultrasonic transmitting / receiving unit at a predetermined cycle, and obtained tomographic image data A digital scan converter having image data constructing means for storing and reading out the interpolated data as tomographic image data, and image display means for displaying image data from the digital scan converter. Was made up.

[0003] In such an ultrasonic diagnostic apparatus, B-mode display, Doppler mode display, and the like are known in order to display a tomographic image or a blood flow image in a subject in real time using ultrasonic waves. However, if the raster interval or the sampling interval of one raster is coarse, the data is drawn by interpolation. Conventional data interpolation includes linear interpolation and interpolation using a sampling function.

That is, in the above-described linear interpolation or interpolation using a sampling function, as shown in FIG. 5, a point X to be obtained is first determined, and two points A, B or around the point X already having sample data are present. Interpolation is performed using a linear function or a sampling function using several points A, B, C, and D to obtain a value of a point X to be obtained.

[0005]

However, in image display by data interpolation in such a conventional ultrasonic diagnostic apparatus, a point having no data is interpolated by an ideal function such as a linear function or a sampling function. Since it is assumed that it is possible, a tomographic image faithful to the actual ultrasonic beam shape may not be able to be drawn. That is, a virtual image such as an image that does not originally exist may be generated by the interpolation. For this reason, diagnosis may not be performed accurately.

Accordingly, the present invention addresses such a problem and uses an ideal function such as a linear function or a sampling function to interpolate between adjacent rasters or between adjacent sample points in one raster. It is an object of the present invention to provide an ultrasonic diagnostic apparatus capable of rendering a tomographic image or a blood flow image by performing interpolation in conformity with an ultrasonic beam shape without using an ultrasonic beam.

[0007]

In order to achieve the above object, an ultrasonic diagnostic apparatus according to the present invention comprises a probe for transmitting and receiving ultrasonic waves to and from a subject, and an ultrasonic diagnostic apparatus which drives the probe to transmit ultrasonic waves. Transmitting and receiving the reflected echo signal, and a tomographic image which repeatedly obtains tomographic image data in the subject including the moving tissue at a predetermined cycle using the reflected echo signal from the ultrasonic transmitting and receiving unit. A digital scan converter having scanning means, data interpolating means for interpolating the obtained tomographic image data, and image data forming means for storing and reading out the interpolated data as tomographic image data; and image data from the digital scan converter. In an ultrasonic diagnostic apparatus having image display means for displaying, the data interpolation means in the digital scan converter, Beam pattern storage means for storing and outputting two-dimensional beam pattern data in the azimuth and depth directions required to interpolate tomographic image data from the layer scanning means is connected, and the above-mentioned is controlled by control means in the digital scan converter. The data interpolation calculation is performed by the data interpolation means using the two-dimensional beam pattern data from the beam pattern storage means.

[0008]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention. The ultrasonic diagnostic apparatus obtains and displays a tomographic image or a blood flow image of a diagnostic site in a subject using ultrasonic waves. As shown in FIG. 2, a receiving circuit 3, a video signal processing circuit 4, a digital scan converter (hereinafter abbreviated as "DSC") 5, a D / A converter 6, a television monitor 7, and a beam pattern memory. 8 is provided.

The probe 1 mechanically or electronically performs beam scanning to transmit and receive ultrasonic waves to and from the subject. Although not shown, the probe 1 includes a source of ultrasonic waves. There is also a built-in vibrator that receives reflected echoes from inside the subject.

The transmission circuit 2 generates a transmission pulse for driving the probe 1 to generate an ultrasonic wave,
The convergence point of the ultrasonic wave transmitted by the built-in wave phasing circuit is set to a certain depth. The receiving circuit 3
Amplifies the reflected echo signal received by the probe 1 with a predetermined gain, and controls the phase by a built-in wave receiving and phasing circuit to apply an ultrasonic beam to one point, a plurality of points, or a continuous convergence point. To form. Further, the video signal processing circuit 4 receives the received signal from the receiving circuit 3 and performs gain correction, log compression, detection, contour enhancement,
It performs signal processing such as filter processing. And
These transmitting circuit 2, receiving circuit 3, and video signal processing circuit 4
Thus, an ultrasonic transmission / reception unit that drives the probe 1 to transmit an ultrasonic wave and processes the received reflected echo signal is configured, and the ultrasonic beam is transmitted by the probe 1 into the body of the subject. By scanning in a certain direction, one tomographic image is obtained.

The DSC 5 uses the reflected echo signal output from the video signal processing circuit 4 to obtain tomographic image data of the inside of the subject including the moving tissue at an ultrasonic transmission cycle. A / D means for reading out data and controlling the system.
It comprises a converter 9, a raster memory 10, an ultrasonic transmission synchronization circuit 11, an interpolation computer 12, a frame memory 13, a television synchronization circuit 14, and a controller 15.

The A / D converter 9 converts a reflected echo signal from the video signal processing circuit 4 into a digital signal. The raster memory 10 includes the A / D converter 9
The stored reflected echo signals (hereinafter referred to as "raster data") are stored in chronological order. The ultrasonic wave transmission synchronizing circuit 11 generates a write timing when writing raster data in the raster memory 10. The A / D converter 9, the raster memory 10, and the ultrasonic wave transmission synchronizing circuit 11 use the reflected echo signal from the ultrasonic transmission / reception unit to determine tomographic image data in the subject including the moving tissue. It constitutes tomographic scanning means which is obtained repeatedly in a cycle.

The interpolation computer 12 serves as data interpolation means for interpolating tomographic image data obtained by the tomographic scanning means. The interpolation computer 12 interpolates raster data output from the raster memory 10 to a frame memory 13 to be described later. It is supposed to be sent.

The frame memory 13 stores the interpolation computer 1
2 to input and write and read data. The television synchronization circuit 14 generates a read timing when tomographic image data is read from the frame memory 13. The frame memory 13 and the television synchronizing circuit 14 constitute image data forming means for storing and reading data interpolated by the data interpolating means as tomographic image data. Note that the controller 15 serves as control means for controlling the operation of each of the above components.

The D / A converter 6 converts the tomographic image data obtained by the DSC 5 into an analog signal. The television monitor 7 receives the analog video signal from the D / A converter 6 and displays it as an image. The D / A converter 6 and the television monitor 7 constitute image display means for displaying the image data from the DSC 5.

Here, in the present invention, the DSC5
The beam pattern memory 8 is connected to the interpolation computer 12 inside. The beam pattern memory 8 serves as beam pattern storage means for storing and outputting two-dimensional beam pattern data in the azimuth and depth directions necessary for interpolating tomographic image data from the tomographic scanning means in the DSC 5. The two-dimensional beam pattern data in the azimuth and depth directions necessary for the interpolation calculation is output to the interpolation computer 12 in the DSC 5 while being stored. A controller 15 in the DSC 5 is connected to the beam pattern memory 8.
The control of 5 causes the interpolation calculator 12 to perform a data interpolation operation using the two-dimensional beam pattern data from the beam pattern memory 8.

The controller 15 determines the timing at which the beam pattern data is sent from the beam pattern memory 8 to the interpolation computer 12, and scans the data output from the raster memory 10 inside the DSC 5 and sends the data to the outside of the DSC 5. A certain beam pattern memory 8
At the appropriate timing, sends out the beam pattern data to the interpolation calculator 12, and operates the interpolation calculator 12 to perform the interpolation calculation, and then writes the calculation result to the frame memory 13 as tomographic image data. Is determined.

Next, the operation of the ultrasonic diagnostic apparatus thus configured will be described. First, the probe 1 shown in FIG.
Is brought into contact with a position corresponding to a diagnosis site of the subject, and an ultrasonic wave is transmitted toward the diagnosis site. At this time, the probe 1
The ultrasonic wave transmitted from the transmission part 2 is formed as a narrow beam or a beam having an appropriate divergence at the diagnosis site by the transmission phasing circuit in the transmission circuit 2. Next, the transmitted ultrasonic beam hits a diagnostic site in the subject and is reflected, and the reflected echo is received by the probe 1,
A reception beam is formed by a reception phasing circuit in the reception circuit 3. In such a state, the ultrasonic wave transmission / reception direction is sequentially changed from the probe 1 at a predetermined cycle, and transmission / reception of the ultrasonic wave is repeated to scan the diagnostic site. The received beam data output from the receiving circuit 3 is input to a video signal processing circuit 4, undergoes necessary signal processing in the video signal processing circuit 4, and is transmitted to the DSC 5 as a reflected echo signal.

Next, the DSC 5 receives the reflected echo signal and converts it into a digital signal by the A / D converter 9. The reflected echo signal converted into the digital signal is input to a raster memory 10 capable of storing a plurality of received beams, and every time the ultrasonic wave receiving direction changes, the address of the raster memory 10 is controlled by the controller 15. Writing and reading are sequentially performed by switching, and the interpolation computer 12 is used as raster data for each sequentially input receiving beam.
Sent to The raster data input to the interpolation calculator 12 includes at least two or more reception beams.

Next, the interpolation computer 12 stores the raster data from the raster memory 10 and the beam pattern memory 8
And the two-dimensional beam pattern data in the azimuth and depth directions read out under the control of the controller 15 from the input device, and performs an interpolation calculation based on these data. And
The result of the interpolation calculation is sent to the frame memory 13 under the control of the controller 15. Next, the frame memory 13
Sequentially stores the input calculation result of the interpolation computer 12 at a predetermined address in the memory under the control of the controller 15, and forms image data to be one tomographic image. Thereafter, the tomographic image data is sequentially read from the frame memory 13 at the read timing generated by the television synchronization circuit 14, and the DSC 5 outputs the tomographic image data.

Next, the frame memory 13 of the DSC 5
Is converted into an analog signal by the D / A converter 6 and transmitted to the television monitor 7. As a result, a tomographic image of the diagnosis site of the subject is displayed on the television monitor 7.

Here, the operation of the interpolation computer 12 will be described in detail with reference to FIGS. First, for the tomographic image data to be written to the frame memory 13, the controller 15 obtains data of one point in the tomographic image data as an address P of the frame memory 13 as shown in FIG. Send to Then, the interpolation computer 12 is controlled by the controller 15
Is converted into a virtual address Q on the raster memory 10 as shown in FIG. At this time, the virtual address Q is not always an address on each raster in the raster memory 10 and is usually an address between adjacent raster data stored in the raster memory 10. Such an address point may be obtained by interpolation.

Further, the interpolation computer 12 obtains four address points Q ₀ , Q ₁ , Q ₂ , and Q ₃ having actual data existing around the virtual address Q on the raster memory 10 shown in FIG. The values (raster data) I ₀ , I ₁ , I ₂ and I ₃ stored at these four address points Q _{0 to} Q ₃ are read from the raster memory 10. Simultaneously with a series of operations from the operation for obtaining the address to the operation for reading the value from the raster memory 10, the interpolation computer 12 calculates the virtual address Q and the four address points Q ₀ on the raster memory 10. , Q ₁ , Q ₂ , and Q ₃ , the addresses R ₀ , R ₁ , R ₂ , and R ₃ storing the data to be read on the beam pattern memory 8 are obtained as shown in FIG. The beam pattern data J ₀ , J ₁ , J ₂ , and J ₃ of R _{0 to} R ₃ are read from the beam pattern memory 8.

Next, with respect to the beam pattern data J ₀ , J ₁ , J ₂ , J ₃ read from the beam pattern memory 8, the raster data I ₀ , I ₁ , After weighting with I ₂ and I ₃ , respectively, and adding, the data I after this addition is written to the corresponding address P of the frame memory 13 shown in FIG. The calculation of the weighting and the addition is performed as shown in the following equation (1). _{I = I 0 × J 0 +} I 1 × J 1 + I 2 × J 2 + I 3 × J 3 ... (1) In this case, sampled at a sufficient sampling interval in the need of pre-beam pattern data in the beam pattern memory 8 Things are stored. Furthermore, raster data sampled at a necessary and sufficient sampling interval may be stored in the raster memory 10. This allows
Interpolation according to the ultrasonic beam shape can be performed without using an ideal function such as a linear function or a sampling function as in the related art.

The frame memory 1 shown in FIG.
The interpolation calculator 12 performs a data interpolation operation so as to configure an operation for obtaining data of one point P in 3 by sequentially changing addresses on the frame memory 13 to form one tomographic image. At this time, as shown in FIG. 3, if a sufficiently accurate interpolation calculation result cannot be obtained with the raster data I _{0 to} I _{3 of} only the four address points Q _{0 to} Q ₃ , Similar interpolation calculation may be performed using the raster data of the point. In this case, it is necessary to store beam pattern data having a width corresponding to the outer raster address in the beam pattern memory 8.

In the case where the sampling interval of the raster data in the raster memory 10 is so fine that interpolation is not necessary, and it is sufficient to form a tomographic image only by interpolation between adjacent rasters, the virtual data shown in FIG. Instead of the four address points Q _{0 to} Q ₃ around the address Q, for example, two points on the raster adjacent to the virtual address Q are obtained, and the two points are similarly determined on the beam pattern memory 8 shown in FIG. It suffices to obtain the values, and both the calculation amount of the interpolation computer 12 and the capacity of the beam pattern memory 8 can be reduced.

Although not shown, the interpolation computer 12
High-speed RA as first storage means for storing data from the raster memory 10 in the input unit on the side of the raster memory 10
M, and a high-speed RAM as second storage means for storing data from the beam pattern memory 8 in an input unit of the interpolation computer 12 on the side of the beam pattern memory 8.
May be provided so that the beam pattern data stored in the second storage means can always be referred to when performing the interpolation calculation based on the data in the first storage means.
In this case, high-speed processing can be performed for interpolation.

[0028]

The present invention has been configured as described above.
A beam pattern storage means for storing and outputting two-dimensional beam pattern data in the azimuth and depth directions necessary for interpolating tomographic image data from the tomographic scanning means is connected to the data interpolation means in the digital scan converter. By controlling the control means in the digital scan converter to perform the data interpolation operation by the data interpolation means using the two-dimensional beam pattern data from the beam pattern storage means, it is possible to perform the operation between adjacent rasters or within one raster. Without using an ideal function such as a linear function or a sampling function to interpolate between adjacent sample points, it is possible to draw a tomographic image or a blood flow image by performing interpolation according to the ultrasonic beam shape. Therefore, as compared with the conventional ultrasonic diagnostic apparatus, a faithful tomographic image conforming to the actual ultrasonic beam shape can be drawn, and generation of a virtual image such as an image which does not originally exist by interpolation can be prevented. From this, diagnosis can be performed accurately and easily.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing a frame memory for explaining an operation of an interpolation computer of the ultrasonic diagnostic apparatus.

FIG. 3 is a diagram showing a raster memory for explaining the operation of the interpolation computer.

FIG. 4 is a diagram showing a beam pattern memory for explaining the operation of the interpolation computer.

FIG. 5 is an explanatory diagram showing an interpolation method performed by using a linear function, a sampling function, or the like in order to interpolate between adjacent rasters or between adjacent sample points in one raster in a conventional ultrasonic diagnostic apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Probe 2 ... Transmitting circuit 3 ... Receiving circuit 4 ... Video signal processing circuit 5 ... DSC 6 ... D / A converter 7 ... TV monitor 8 ... Beam pattern memory 9 ... A / D converter 10 ... Raster memory 11 ... Ultrasonic transmission synchronization circuit 12 ... Interpolation computer 13 ... Frame memory 14 ... TV synchronization circuit 15 ... Controller

Claims (1)

[Claims] A probe for transmitting / receiving an ultrasonic wave to / from a subject; an ultrasonic transmitting / receiving unit for transmitting the ultrasonic wave by driving the probe and processing a received reflected echo signal; Tomographic scanning means for repeatedly obtaining tomographic image data in a subject including a moving tissue using a reflected echo signal from the transmitting and receiving unit at a predetermined period, data interpolating means for interpolating the obtained tomographic image data, and the interpolated data An ultrasonic diagnostic apparatus comprising: a digital scan converter having image data forming means for storing and reading data as tomographic image data; and an image display means for displaying image data from the digital scan converter. For the interpolation means, the secondary in the azimuth and depth direction necessary to interpolate the tomographic image data from the tomographic scanning means A beam pattern storage means for storing and outputting original beam pattern data is connected, and a data interpolation operation is performed by data interpolation means using two-dimensional beam pattern data from the beam pattern storage means under the control of a control means in the digital scan converter. An ultrasonic diagnostic apparatus characterized by performing the following.