JPS6314626B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic diagnostic apparatus that can simultaneously display still images and real-time moving images.

There are two types of ultrasonic diagnostic devices: those using a contact compound method and those using an electronic scan method. Among these, the contact compound method, as shown in Fig. 1, uses a single ultrasonic probe 3 attached to the tip of a scanner arm 2 to manually scan the affected area of the human body 1, as shown in Fig. 2. The tomographic image 4 is displayed on a monitor. Although such a contact compound type ultrasonic diagnostic apparatus has the advantage of being able to obtain still images with a large field of view, it has the disadvantage of not being able to display real-time moving images because scanning is performed manually. On the other hand, the electronic scan method uses a probe with multiple ultrasonic transducers arranged in an array.
Because each transducer is operated in sequence to obtain a tomographic image, it is suitable for obtaining real-time videos, but it does not have the function to detect the position of the probe, so it is difficult to obtain still images with a large field of view. It has the disadvantage of not being able to

Recently, in order to compensate for the shortcomings of each of the above methods, a device has been developed that combines the functions of both methods and switches between them as appropriate to obtain real-time moving images using an electronic scan and large-field still images using a contact scanner. has been proposed, but this device cannot display large-field still images and real-time video at the same time, making it difficult to know the relative positions of the images, making it difficult to identify tissues convincingly. There was a flaw in it.

There is also a proposal to simultaneously display real-time video from an electronic scan and still images from a contact scanner using different areas on one monitor, but the position of the large-field still image and the real-time video remains In particular, it was difficult to determine which part of the human body the video was from.

Furthermore, a device has been proposed in which a single probe and an electronic scan probe are attached to the same scanner arm to obtain an image using the conventional contact compound method and a real-time image using the electronic scan method at a position close to the contact compound method. Although the probes are located close to each other, the images obtained from each probe are strictly speaking from different locations. It is difficult to ascertain which part it belongs to, and the identification has not yet been convincing.

The present invention has been made in view of the above circumstances, and includes an electronic scan probe attached to a scanner arm capable of mechanical position detection, and allows this probe to perform scanning by the contact compound method, while also performing scanning by the electronic scan method. The object of the present invention is to provide an ultrasonic diagnostic apparatus that can simultaneously display a still image with a large field of view and a part of a real-time moving image included therein.

The present invention will be specifically explained below using Examples.

FIG. 3 is a perspective view showing the positional relationship between the ultrasound probe, which is part of the apparatus of the present invention, and the human body. This device has an electronic scan probe 5 attached to a scanner arm 6 that can detect the position, and in combination with a control system, which will be described in detail later, first scans the electronic scan probe 5 using a contact compound method. Obtain a still image 7 with a large field of view in Fig. 4, and then switch to the electronic scanning method and scan to obtain a real-time moving image (hatched area 8 in Fig. 4) of the current position of the probe 5. I have to. In addition, in Figure 3
HD is Sukiyanahed.

Next, the basic principle of the present invention will be explained with reference to FIG. Generally, to obtain a tomographic image, the brightness signal Z
In addition, the emission position and direction of the ultrasonic beam must be detected. Here, if a certain point on the tomographic plane is the origin X, Y = 0, 0, then the emission position of the ultrasonic beam, that is, the center position Xp, Yp of the transducer surface and the directions ΔX, ΔY of the ultrasonic beam are detected. There is a need. The scanner arm 6 is the same as the arm of the conventional single-probe contact compound system, and basically consists of three arms (a first arm 9 with a length R ₁ , a second arm ₁ with a length R 2).
0 and a third arm 11) with a length R ₃ , each joint can be rotated manually, and the angles θ ₁ , θ ₂ , θ ₃ of the joints can be detected.
Here, the base point O of the first arm 9 is set as the origin 0,0,
The X axis is the horizontal right direction and the Y axis is the vertical upward direction, and the angle of each joint from the horizontal direction (X axis) is θ ₁ ,
Let θ ₂ and θ ₃ be. In this case, the coordinates Xpo and Ypo of the tip of the third arm 11 are determined by the following equations (1) and (2).

Xpo=R ₁ cosθ ₁ +R ₂ cosθ ₂ +R ₃ cosθ ₃ ...(1) Ypo=R ₁ sinθ ₁ +R ₂ sinθ ₂ +R ₃ sinθ ₃ ...(2) Also, the ultrasonic wave at the position of the above coordinates Xpo and Ypo The beam directions ΔXpo and ΔYpo are determined by the following equations (3) and (4).

ΔXpo=cosθ ₃ ...(3) ΔYpo=sinθ ₃ ...(4) Let Po be the emission point on the central axis of the ultrasonic beam emitted from the electronic scan probe 5 attached to the tip of the third arm 11. , along its axis, sequentially the emission point of the other ultrasonic beam in the right direction
P ₁ , ..., Pi, ..., Pn, and the emission points of other beams are set sequentially along the left direction as P- ₁ , ..., Pi, ..., P-
When n is the interval between each beam and d is the interval between each beam, the coordinates Xpi and YPi of the ultrasonic beam Pi at any position are given by the following equation (5),
It is determined by (6).

Xpi=R ₁ cosθ ₁ +R ₂ cosθ ₂ +R ₃ cosθ ₃ −Dsinθ ₃ ...(5) Ypi=R ₁ sinθ ₁ +R ₂ sinθ ₂ +R ₃ sinθ ₃ +Dcosθ ₃ ...(6) Here, D=id, i=-n,-(n-1),...-
It is given by 1, 0, 1, ..., n (where n is a positive integer, and in this example the ultrasound beam is 2n+
(The case of one is shown).

Then, the directions ΔXpi and ΔYpi of the ultrasound beam Pi at the arbitrary position are determined by the following equations (7) and (8).

ΔXpi=ΔXpo=cosθ ₃ ...(7) ΔYpi=ΔYpo=sinθ ₃ ...(8) Therefore, the control system described later calculates each of the above equations to find the position and direction of each beam, and the result is An ultrasonic tomographic image can be obtained by displaying it on a monitor in accordance with the above.

FIG. 6 is a block diagram of an embodiment showing the configuration of a control system for realizing the above principle. Reference numeral 12 receives voltage output signals from angle detectors 13a to 13c that detect the angles θ ₁ , θ ₂ , and θ ₃ of each joint of the scanner arm 6, and calculates the equations (1) and (2) above. This is a first analog calculation circuit that calculates the coordinates Xpo and Ypo of the position Po of the tip of the third arm 11, and calculates the beam directions ΔXpo and ΔYpo by calculating the equations (3) and (4). 14 is the electronic scan probe 5
Each of the transducers 5a to 5n is driven to emit an ultrasound beam, and the echo signals obtained from each transducer are converted into electrical signals to generate an ultrasound image signal Z and the position of the currently emitted ultrasound beam. This is an electronic scanning circuit that outputs a signal Sp indicating . 15 is the central ultrasound beam from the analog calculation circuit 12;
Input Po's position coordinate signals Xpo and Ypo, and
The position display signal Sp of the selected ultrasonic beam from the electronic scanning circuit 14 is input, and the calculations of equations (7) and (8) are performed to correspond to the position coordinates Xpi and Ypi of the emission point of each ultrasonic beam. a second signal that outputs a signal to
This is an analog calculation circuit. Reference numeral 16 supplies the respective outputs ΔXpo, ΔYpo, Xpi, and Ypi from the first and second analog calculation circuits 12 and 15 to the next-stage digital scanning converter 18 in a time-sharing manner according to the control signal from the controller 17. A switching device (for example, a multiplexer) for switching transmission. The controller 17 outputs a control signal Sc for the switch 16 and a control signal S _T for synchronously operating the electronic scanning circuit or digital scanning converter 18, and is equipped with a switch 20. switch 2
0 is for switching the scanning method, for example, when opened, 1 in the electronic scan probe 5
Only one firing point (eg, central beam Po) is excited to enable contact compound scanning, and closed to enable electronic scan scanning. The digital scan converter 18 has an image memory and receives the ultrasound position vector signals Xpi,
High-speed calculation of the memory address to be stored using Ypi, ΔXpi, ΔYpi and sequentially writing the digitized ultrasound image signal Z to the location,
It outputs a composite video signal Sv for TV display, and is composed of, for example, a digital scan converter that can update the written content. A TV monitor 19 displays an image of the data Sv read out from the digital scan converter 18. In this case, reading from the digital scan converter 18 is performed in synchronization with the TV scanning period.

Next, the operation of the apparatus of the present invention will be explained with reference to the time chart shown in FIG. First, when the switch 20 provided in the controller 17 is opened, the electronic scanning circuit 14 excites and drives only the central transducer of the ultrasound probe 5, and the probe 5 is manually scanned using the contact compound method. Scanning becomes possible. The position and direction of the ultrasound beam at the center of the probe 5 are calculated by the first and second analog calculation circuits 12 and 15, and the calculation results are sent to the digital scanning converter 18 via the switch 16. A memory address corresponding to the position and direction of the ultrasound beam is selected, and the digital value of the ultrasound image signal Z obtained from the electronic scanning circuit 14 is written to that address, and further synchronized with the TV raster. reading is being performed
displayed on the TV monitor 19. At this time, by moving the probe 5 over a wide range including the diagnostic target site of the human body 1, a still image 21 with a large field of view as shown in FIG. 8 can be obtained.

Next, the still image 21 is observed, the probe 5 is placed at a position on the human body 1 that corresponds to a part that is considered to be particularly necessary, and the switch 20 is closed. In this case, scanning by the electronic scanning method is performed as follows. Electronic scanning circuit 1
4 sequentially excites each of the transducers 5a to 5n in the ultrasonic probe 5, and sequentially processes the echo signals obtained therefrom and outputs them as an ultrasonic video signal Z. At the same time, the angles θ ₁ to _{θ 3} of each joint of the scanner arm 6 at this time are detected, and based on this detection signal, the first analog calculation circuit 12 calculates the position coordinates Xpo, Ypo of the ultrasonic beam Po at the center. and its directions ΔXpo, ΔYpo are calculated, and the position coordinates Xpi, Ypi of each ultrasound beam Pi are determined by the second analog calculation circuit 1 in relation to the position coordinates Xpo, Ypo.
Calculated at 5. These calculation results are sent to the controller 17.
Switch 1 controlled by a control signal Sc from
6 in a time-division manner and input to a digital scan converter 18. The timing of each of these signals is as shown in FIG. That is, FIG. 7a shows a repetitive pulse (rate pulse) Rp to limit the ultrasound emission time, and an ultrasound image signal Z (FIG. 7b) is sent in synchronization with this rate pulse Rp. In addition, the position vector signal of the ultrasound beam, that is, the position information signal Xpi of the ultrasound emission point Pi,
Ypi and the direction signals ΔXpi, ΔYpi are the switching device 1
Immediately after the arrival of the ultrasonic rate pulse Rp, Xpi → ΔXpi,
The signals are input to the digital scanning converter 18 as pairwise signals such as Ypi→ΔYpi. The digital scanning converter 18 digitizes the ultrasonic video signal Z at high speed into a predetermined address of the image memory calculated based on the input information of the ultrasonic beam position vector signals Xpi, Ypi, ΔXpi, and ΔYpi. I will write it in. Therefore, the portion corresponding to the position where the ultrasound probe 5 is placed, ie,
Only part of the image memory remains for a certain period of time (e.g. 1/30
As shown in FIG. This means that it can be displayed as a real-time video. In this case, by manually moving the probe 5 while keeping the switch 20 closed (that is, keeping the electronic scanning system scanning), the real-time video can be easily changed to a video of another diagnostic site.

According to the above-mentioned device, first a large field of view still image is obtained using a contact compound scan method using one probe, and then a real-time video is obtained at an arbitrary position in the still image based on an electronic scan method. It is possible to provide an ultrasonic diagnostic device capable of Therefore, it is possible to clearly determine which part of the tissue the obtained ultrasound image belongs to, and it is possible to improve the persuasiveness of identification at the time of diagnosis. For example, it becomes extremely easy to determine the movement of the fetus and its positional relationship with the mother's body.

The present invention is not limited to the embodiments described above, but can be modified in various ways.

For example, in the embodiment described above, an analog calculation circuit was used to calculate the position vector of the ultrasonic beam, but it is also possible to implement this using a digital processing circuit. In this case, the following equations (9) and (10) may be used as equations for calculating the positions Xpi and Ypi of the ultrasound beam Pi in order to shorten the calculation time.

Xpi=XPo−Dsinθ ₃ ...(9) Ypi=Ypo+Dcosθ ₃ ...(10) In other words, as is clear from the previous equations (5) and (6), the electron In scan type scanning, it is sufficient to calculate only D as a variable.

Further, in the above embodiment, in the case of contact compound scanning, only one central vibrator is selected and excited, but the present invention is not limited to this, and a still image can be obtained by exciting multiple or all vibrators. It's okay. In this way, a still image over a wide range can be obtained with one manual scan, contributing to faster diagnosis.

Furthermore, although the above embodiment shows a case in which a linear type electronic scan probe is attached to the scanner arm 6, the same purpose may be achieved by attaching a sector type electronic scan probe or a mechanical linear scan probe instead. good. Here, in the case of sector type scanning, when the scanner arm 6 is at a constant position, the ultrasonic emission position vector is obtained by the following equations (11) to (14), and since θi is a variable, the calculation is further becomes easier.

Xpi＝Xpo……(11) Ypi＝Ypo……(12) ΔXpi＝cos(θ ₃ +θi)……(13) ΔYpi＝sin(θ ₃ +θi)……(14)

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a conventional contact compound type device, Fig. 2 is an explanatory diagram of a still image obtained by the device, and Fig. 3 shows the positional relationship between the ultrasound probe used in the device of the present invention and the human body. 4 is an explanatory diagram of a display image for explaining the principle of the device of the present invention, FIG. 5 is an explanatory diagram of the operating principle of the present invention, and FIG. 6 is an illustration of a configuration of the control system of the present invention. An embodiment block diagram, FIG. 7 is a time chart for explaining the operation of the present invention, and FIG. 8 is an explanatory diagram showing one aspect of a display image obtained by the present invention. 1...Human body, 5...Electronic scan probe, 6
...Sciyana Arm, 12,15...Calculation circuit,
13a-13c...Angle detector, 14...Electronic scanning circuit, 16...Switcher, 17...Controller, 18
...Digital scan converter, 19...Monitor, 2
1...Large field of view still image, 22...Real time video.

Claims (1)

[Claims] 1 Arm position detection means for detecting the position of a freely moving mechanical arm moving tip in a predetermined spatial coordinate system, and a plurality of vibrators attached to the arm moving tip and sequentially scanned by the control of a scanning means. an ultrasonic probe provided with the ultrasonic probe; a first calculating means for calculating a distance between the emission position of the ultrasonic beam in the ultrasonic probe and the attachment position of the moving end of the arm; and an ultrasonic beam emitted from the ultrasonic probe; second calculation means for calculating the firing position and direction in the coordinate system of the mechanical arm based on the outputs of the arm position detection means and the first calculation means; 1. An ultrasonic diagnostic apparatus comprising: a control means for displaying an ultrasonic image by sequentially scanning a sonic probe.