JPH0559737B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an image display method in an ultrasonic diagnostic apparatus.

(B) Prior art In general, ultrasound diagnostic equipment transmits ultrasonic waves from a probe toward a subject, and the probe receives the reflected waves from the subject again, converting them into electrical echoes. This echo signal is stored in a storage device as an image signal. The diagnostic image is then displayed on a monitor such as a CRT by reading out the stored image signal from the storage device at a TV scanning speed.

By the way, in a conventional ultrasonic diagnostic apparatus, a diagnostic image displayed on a monitor is a one-dimensional or two-dimensional planar image. For this reason, there is a problem in that it is difficult to understand the three-dimensional relationship between the diagnostic sites. In other words, there is a problem in that the three-dimensional relationship can only be inferred from individually displayed two-dimensional images and cannot be directly observed.

In addition, there was a problem in that it was completely impossible to display planes inside the subject that could not be scanned by the probe (for example, planes parallel to the surface of the subject).

(c) Purpose The present invention has been made in view of the above-mentioned problems. The purpose of this invention is to enable display of cross-sectional images in any direction based on the original image, thereby solving various problems of the prior art.

(d) Configuration In order to achieve such an object, the present invention stores a plurality of diagnostic images obtained by scanning a probe in parallel to a subject in a storage device, and then displays the diagnostic images. to specify a desired cross section, read image data from the storage device according to the specified cross section,
By sequentially shifting the memory addresses vertically and horizontally and overwriting them in the two-dimensional memory, and interpolating between the edge lines of the mutually adjacent diagnostic images using an interpolation method, a continuous three-dimensional diagnostic image of the desired cross section is displayed on the monitor. I am trying to display it.

(E) Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram of an ultrasonic diagnostic apparatus according to the present invention. In the figure, 1 is an ultrasonic diagnostic device, 2 is a probe, 4 is an A/D converter that digitizes the echo signal output from the probe 2, and 6 is an image signal that converts the digitized echo signal into an image signal. 8 is the writing of this storage device 6,
This is a storage device control circuit that controls reading. Further, 10 is a display monitor such as a CRT, 12 is a two-dimensional memory for displaying diagnostic images on the monitor 10, and 14 is a two-dimensional memory write control circuit for controlling addresses for writing into the two-dimensional memory 12. ,1
Reference numeral 6 denotes a readout display control circuit for reading out the stored contents of the two-dimensional memory 12 and outputting the same to the monitor 10. First and second latch circuits 18 and 20 sequentially latch echo signal data corresponding to positions on the edge line of a plurality of diagnostic images obtained by scanning the probe 2 in parallel. 22 is the first,
a switching circuit 24 for switching the second latch circuits 18, 20;
This is an interpolation calculation circuit that calculates the value of each pixel point between the edge lines of mutually adjacent diagnostic images by interpolation based on the echo signal data on the edge lines each latched at 0. Further, 26 is a central control circuit (hereinafter referred to as CPU) for controlling the entire ultrasonic diagnostic apparatus 1, and 28 is an operation panel for inputting signals for operating this CPU 26.

A three-dimensional image display method using the ultrasound diagnostic apparatus 1 having the above configuration will be described.

First, as shown in FIG. 2, the probe 2 is scanned parallel to the subject, and echo signals are collected at regular intervals. Each collected echo signal is sent to an A/D converter 4,
It is stored in the storage device 6 via the storage device control circuit 8. Therefore, the storage device 8 stores a plurality of diagnostic images P ₁ , P ₂ . . . taken at equal intervals.
In parallel with the above, the echo signals from the probe 2 are sequentially stored as image data in the two-dimensional memory 12 via the two-dimensional memory write control circuit 14. In this case, the two-dimensional memory write control circuit 14 sets the write memory address of the two-dimensional memory 12 to
It is specified by shifting it little by little vertically and horizontally in the direction and the Y direction perpendicular to this direction. In this way, the two-dimensional memory 12
If the diagnostic images P ₁ , P ₂ . . . superimposed on the top are displayed as they are on the monitor 10, the result will be as shown in FIG. 2. In other words, the sample interval in the Z direction, which corresponds to the scanning direction of the probe 2, is rougher than the sample intervals in the X and Y directions, so that a continuous three-dimensional image cannot be obtained.

Therefore, as shown in FIG. 3, two adjacent diagnostic images P ₃ and P ₄ superimposed on the two-dimensional memory 12 are defined as an ABFG plane and a CDEH plane, respectively.
To display a continuous ABDC surface and BFED surface between the edge lines of AB and CD and between the edge lines of BF and DE. To do this, first, the CPU 26 reads each image data corresponding to the positions on the AB and CD edge lines stored in the two-dimensional memory 12, and the data on the AB line is sent to the first latch circuit via the switching circuit 22. Latch at 18. Further, the data on the CD line is latched by the second latch circuit 20 by switching the switching circuit 22. Each AB latched by the first and second latch circuits 18 and 20
The image data on the line and the CD line are respectively output to the interpolation calculation circuit 24. In the interpolation calculation circuit 24,
Based on image data on AB and CD lines,
Data for each pixel point on the ABDC plane is calculated by interpolation. For example, as shown in Figure 4,
When calculating the brightness of one pixel point R on the ABDC plane, the distances from the CD line to the R point and the AB line are respectively X ₁ and X ₂ , and this pixel point R
If the brightness on the CD line and the AB line corresponding to the above are P and Q, respectively, the brightness of the pixel point R is given by {X ₁ ·Q+(X ₂ −X ₁ )P}/X ₂ . In this way, the interpolation calculation circuit 24 calculates
Data at each pixel point within the ABDC plane is written to an address position between both edge lines AB and CD of the two-dimensional memory 12 via the two-dimensional memory write control circuit 14. In the same way, the image data corresponding to the positions on each edge line of BF and DE in Fig. 3 are also processed by the CPU 2.
6, the interpolation calculation circuit 24 calculates the data of each pixel point in the BFDE plane, and then the two-dimensional memory 12
Write again. In this way, interpolation is performed between each edge line of mutually adjacent diagnostic images P ₁ , P ₂ , P ₂ , P ₃ , P ₃ , P _{4 .} . . . Then, the display control circuit 1 reads out the storage contents of the two-dimensional memory 12.
6, a perspective view of a rectangular parallelepiped having continuous surfaces is displayed on the screen. In other words, continuous three-dimensional diagnostic images can be obtained.

When a three-dimensionally displayed diagnostic image as shown, for example, in FIG. 5 is obtained in the above manner, a method of displaying a three-dimensional image cut at an arbitrary cross section of this rectangular parallelepiped will be described next. First, by operating the operation panel 28, a desired cross section on this rectangular parallelepiped is designated by two edge lines, such as PPn and PnQn in the figure. When each line of PPn and PnQn is specified, the CPU 26 calculates the cross section PQQnPn from the plurality of image data already stored in the storage device 6.
The image data corresponding to the upper position is sequentially read out,
This is written into the two-dimensional memory 12 via the storage device control circuit 8 and the two-dimensional memory write control circuit 14.
If a diagnostic image is displayed in this state, it will be as shown in FIG. Therefore, the CPU 26 reads image data for one line between PQ from the storage device 6, sends this image data through the switching circuit 22 to the first latch circuit 18, and latches it there. Next, the CPU 6 switches the switching circuit 22 to read one line of data between P ₁ Q ₁ from the storage device 6, sends this image data through the switching circuit 22 to the second latch circuit 20, and latches it there. put.

Further, the CPU 26 specifies a pixel point (x, y) on the plane PQP ₁ Q ₁ and notifies the two-dimensional memory write control circuit 14 and the interpolation calculation circuit 24 of this. Interpolation calculation circuit 24 that receives specification of pixel point (x, y)
Similarly, p ₀ and q ₀ are transferred from the first latch circuit 18 to the second latch circuit 18.
As we said, p ₁ and q ₁ from the latch circuit 20.
On the PQ line, P ₁ Q ₁ line, the pixel point (x,
y), calculate the image data of the pixel point (x, y) by interpolation based on the image data of each point, and write the calculated data to a two-dimensional memory. The signal is sent to the control circuit 14.
The two-dimensional memory write control circuit 14 to which the data of the pixel point (x, y) is sent writes this data to a point in the two-dimensional memory 12 corresponding to the pixel point (x, y).

In this way, the operation is performed on all pixel points on the plane PQP ₁ Q ₁ , and furthermore, on the plane P ₁ Q ₁ P ₂ Q ₂ , ~ plane
By doing the same for P _o-1 Q _o-1 P _o Q _o ,
An image of the cross section PQP _o Q _o , which is a collection of these planes, is obtained. Furthermore, the image of the surface PTP _o T _o is also
PQP _o can be obtained in the same way as Q _o .

Then, from the surface PQP _{o Qo} image obtained in this way, the surface PTP _{o To} image, and the image of the surface P _o Q _o S _o To obtained by the probe 2, _an arbitrary A stereoscopic image of the rectangular parallelepiped PQP _o Q _o −TST _o S _o including the cross section of is obtained. FIG. 7 shows a three-dimensional diagnostic image obtained in this manner and displayed on the monitor 10. In addition to the above-mentioned example, edge lines can be specified to obtain a desired cross-section by ABC, DEF, or even GHI, as shown in FIG. 8, to obtain an inclined cross-section. Furthermore, by moving and rotating the three-dimensionally displayed diagnostic image, any cross section can be displayed.

(f) Effects As described above, according to the present invention, a three-dimensional image including an arbitrary cross section is displayed, so that a region near the display of the object and parallel to the object is displayed. This makes it easier to understand the three-dimensional relationships within the subject, including diagnostic areas that are difficult to scan with a probe, and has the excellent effect of enabling more accurate diagnosis.

[Brief explanation of drawings]

The drawings show embodiments of the present invention; FIG. 1 is a block diagram of an ultrasonic diagnostic apparatus according to the present invention, and FIGS. 2 to 8 are explanatory diagrams of display of three-dimensional diagnostic images. 1... Ultrasonic diagnostic device, 10... Monitor, 12
... Two-dimensional memory, 24 ... Interpolation calculation circuit, 26
...Central control circuit.

Claims (1)

[Claims] 1 After storing a plurality of diagnostic images obtained by scanning the probe parallel to the subject in a storage device, displaying the diagnostic images and specifying a desired cross section, By reading image data from the device, sequentially shifting the memory addresses vertically and horizontally and overwriting it on a two-dimensional memory, and interpolating between the edge lines of the diagnostic images adjacent to each other using an interpolation method, a desired cross section can be displayed on the monitor. An image display method in an ultrasonic diagnostic apparatus, characterized in that continuous three-dimensional diagnostic images are displayed.