JPS6224095B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses an ultrasonic tomographic image diagnostic apparatus and an ultrasonic blood flow meter to measure the blood flow velocity at any point within the tomographic image displayed at the same time as the tomographic image measurement. The present invention relates to a possible ultrasonic diagnostic device.

Conventionally, it has been possible to obtain blood flow velocity at any depth from the body surface using a pulsed Doppler type ultrasonic blood flow meter, but it has not been clear which part of the body is being measured. Therefore, there is a method that simultaneously displays the so-called A-mode signal, which one-dimensionally displays the ultrasound reflected signal over time, and the blood flow velocity measurement point as a range gate, but it is still difficult to identify the body part, and the blood flow meter is used to quantify the There were problems with conversion and reproducibility.

There is also a device that fixes a tomogram probe and a blood flow meter probe at a fixed angle and measures blood flow at an arbitrary depth in a specific direction within a tomogram. This method is inappropriate when the body surface site where the optimal tomographic image is obtained and the body surface site where the optimal blood flow measurement is performed differ depending on the subject, as in the case of the present invention.

An object of the present invention is to provide an ultrasonic diagnostic apparatus that can obtain an ultrasonic tomographic image from the body surface and simultaneously measure blood flow velocity at any point from any direction within the tomographic image.

Hereinafter, the present invention will be explained in detail with reference to Examples. In FIG. 1, numeral 1 is a probe of an electronic scanning sector-shaped ultrasonic tomographic image diagnostic apparatus, and terminal a is an output terminal. 2 is a probe of a pulsed Doppler type ultrasonic blood flow meter, and terminal b is an output terminal. These two probes are each held by an arm by a rotating shaft perpendicular to the plane of the paper, and these arms are also connected to each other by a rotating shaft perpendicular to the plane of the paper. Therefore, the relative positions and angles of both probes can be set freely. 3
is a reference pulse oscillator (eg, repetition frequency 5 kHz), and an example of its oscillation waveform is shown in FIG. 2a. 6 is a 1/n frequency divider, and the output when n=5 is shown in FIG. 2b. 5 is a switch,
The output of the frequency divider 6 is used as a control signal, and when this control signal is 1, the switch 5 is turned off, and when the control signal is 0, the switch 5 is turned on. The output waveform of switch 5 is shown in FIG. 2c. 8 is an ultrasonic tomographic diagnostic device (hereinafter abbreviated as a tomographic device), 9 is an ultrasonic blood flow meter (hereinafter abbreviated as a blood flow meter), 10 is a position detection unit of a blood flow meter probe, and 11 is a blood flow meter. Meter display signal generator, 12 is the monitor's XYZ signal changeover switch, 1
3 is a monitor.

4 is a mode switching control signal generator, and 7 is a changeover switch. When the output of the control signal generator 4 is 1, the output of the switch 5 is input to the tomography device 8, and the output of the frequency divider 6 is input to the blood flow meter 9. Let them input. In this case, tomographic image measurement is primarily performed, and blood flow measurement is secondary. Conversely, when the output of the mode switching control signal generator 4 is 0, the switch 5
The output of the frequency divider 6 is input to the blood flow meter 9, and the output of the frequency divider 6 is input to the tomographic image device 8. In this case, blood flow measurement is performed primarily and tomographic image measurement is used as a secondary method. 13, 14 and 1
5 are sin and cos potentios, and from the mutual angles of the probes 1 and 2 and the two arms connecting them, sin θ ₁ , cos θ ₁ , as shown in FIG. 3, respectively.
Sinθ ₂ , Cosθ ₂ , Sinθ ₃ , and Cosθ ₃ are detected and input to the position detection section 10 . At the same time, Sinθ
₀₃ and Cos θ ₃ are input to the display signal generator 11.
The position detection unit 10 performs calculations to be described later and outputs the coordinates (X ₀ , Y ₀ ) of the vibration plane of the blood flow meter probe. In addition, the A mode signal is sent from the terminal 9-1 of the blood flow meter 9, the range gate signal of the blood flow measurement point is sent from 9-2, and the distance mark signal is sent from 9-3 (for example, a distance of 1 cm).
(repetitive pulses with a time of 13 milliseconds divided by 1/2 the speed of sound (1500 m/s)) are input to the blood flow meter display signal generation section 11 from one side. Note that the blood flow meter that generates the three signals described above is well known, so the details will be omitted. On the other hand, Sin θ 3 and Cos _{θ 3} indicating the angle θ ₃ of the axis of the probe 2 with respect to the axial direction of the probe 1 are input from the Sin, Cos potentiometer ₁₅ to the display signal generator 11, and the calculations described below are performed. X sweep for flow meters; X _D , Y sweep; Y _D and Z sweep; Z
_D (constant) is obtained. Switch 12 is for the monitor.
It is an XYZ signal changeover switch, and when the control signal (same as the control signal of tomography device 8) is 1, the
XYZ signals to terminals 12-1, 12-2, 1 respectively
Output from 2-3. When the control signal of the switch 12 is 0, the XYZ signals of the blood flow meter display signal generator 11 are sent to the terminals 12-1, 12-2, 12-3, respectively.
Output from The output of the switch 12 is the monitor 13
is input and displayed.

Further, the blood flow meter probe position detection section 10 and the blood flow meter display signal generation section 11 will be explained in detail. First, the position detection section 10 will be explained. Third
As shown in the figure, the length of the tomography probe 1 is l ₁ , the length of the blood flow meter probe 2 is l ₃ , and the Sin and Cos potentios are 1.
The distances between 3 and 14 and between 14 and 15 are both l ₂ , the axial direction of the tomography probe 1 is the X axis, the tip of the tomography probe 1 is the origin (0,0), and the potentio 13 , 14, and 15, the angles from the X-axis direction are θ ₁ , θ ₂ , and θ _{3 ,} respectively, then the coordinates (X ₀ , Y ₀ ) of the tip of the blood flow meter probe are X ₀ =−l ₁ +l ₂ cosθ ₁ +l ₂ cosθ ₂ +l ₃ cosθ ₃ }
(1) Y ₀ = l ₂ sin θ ₁ + l ₂ sin θ ₂ + l ₃ sin θ ₃ . Therefore, in the position detection section, the calculation of equation (1) may be performed.

Next, the blood flow meter display signal generating section 11 will be explained. As shown in FIG. 4 a, b, and c, the A mode signal, the range gate signal of the measurement point, and the distance mark signal are output from 9-1, 9-2, and 9-3 of the blood flow meter 9, respectively, and the display signal is Input to the generating section 11. Let these sum signals be g(t).

g(t) ≡ {(A mode signal) + (range gate signal) + (distance mark signal)} (2) Now, to display g(t) perpendicular to the beam direction indicator line of the blood flow probe. is the X sweep X _D and the Y sweep Y _D as shown in Figure 5. Here, k is a constant and t is a time calculation. Note that the circuit for calculating equations (1) and (3) can be easily created by a person skilled in the art, so the description thereof will be omitted. Of course, a computer may be used. The reason for superimposing A mode perpendicularly to the beam direction line of the blood flow probe is that by simultaneously observing the tomographic image and A mode, the relative position of the tomography probe and the blood flow probe can be determined. This is because accuracy can be confirmed. It will be explained below that with such a configuration, it is possible to obtain blood flow signals in any direction and at any point within a tomographic image in real time.

First, the output of the mode switching control signal generator 4 is set to 1 in order to mainly perform tomographic image measurement and to make blood flow measurement secondary.
The output of the gate 5 becomes the control signal of the tomography device 8 by the changeover switch 7, and the output of the frequency divider 6 becomes the control signal of the blood flow meter 9.
This becomes the control signal. Therefore, the tomographic image is, for example, a scanning line
128 lines, 40 frames/sec, repetition frequency 5K
Hz. Also, when n = 5 of the frequency divider, the repetition frequency of the blood flow meter is 1KHz, and the frequency deviation of the blood flow that can be detected is up to 500Hz according to sampling theory.
becomes. Therefore, since the measurement range of blood flow velocity becomes very narrow, blood flow is not measured, but only the blood flow measurement site is monitored.

That is, in the position detection unit 10, the tip (X ₀ , Y ₀ ) of the blood flow meter probe 2 is calculated using equation (1), and the blood flow meter display mechanism 11 calculates the A mode signal and range shown in FIG. The gate signal and the distance mark signal are superimposed perpendicularly on the display line in the ultrasonic beam direction of the blood flow meter probe, and are displayed on the monitor 13 through the switch 12 in FIG.

Next, the output of the mode switching control signal generator 4 is set to 0 in order to mainly perform blood flow measurement and secondary tomographic image measurement.
The output of the gate 5 is connected to the blood flow meter 9 by the changeover switch 7.
The output of the frequency divider 6 is transmitted to the tomography device 8.
This becomes the control signal. Therefore, the tomographic image is, for example, a scanning line
There are 128 lines and 8 frames/sec, which causes the image to flicker. However, the number of repetitions of the blood flow meter is approximately 5K.
Hz, so the frequency deviation of the detectable blood flow is
It is 2.5KHz, which is a practical value based on the intracardiac blood flow velocity.

In the above explanation, the frequency divider n=5, but it is clear that n=2, that is, it is also possible to alternate tomographic image measurement and blood flow measurement. In this case, the tomographic image has 128 scanning lines, 20 frames/sec,
Blood flow meter repeats 2.5KHz, maximum frequency deviation
It is 1.25KHz, which is practical.

In the present invention, the sin and cos potentios are used as sensors for detecting the position of the blood flow probe, but it is clear that the θ potentio may be used and sin and cos conversion may be performed in a circuit.

In addition, in the present invention, the A mode obtained by the blood flow probe is displayed superimposed on the tomographic image.
It is clear that this A-mode can be used to obtain an Ultrasound Cardiogram by a normal M-mode scan on other monitors.

As explained above, according to the present invention, by combining an ultrasonic tomographic diagnostic device and an ultrasonic blood flow meter, the blood flow velocity in any direction and any position within a tomographic image can be measured, and the blood flow It will greatly contribute to the quantification and improvement of reproducibility of measurements.

In the above explanation, an electronic scanning sector-shaped ultrasonic tomography diagnostic apparatus and a pulsed Doppler ultrasonic blood flow meter were used. However, it is clear that the same problem will occur even if an electronic scanning linear type device is used as the tomographic diagnostic device.

In addition, in the present invention, two probes were used and were controlled in a time-series manner to perform tomographic images and blood flow measurements, but one probe (array transducer) was controlled in a time-series manner. It is clear that the same holds true. In this case, there is an advantage that a position detection mechanism is not required, but
It is impossible to independently install and measure tomographic images and blood flow at optimal positions.

[Brief explanation of the drawing]

FIG. 1 is an embodiment of the present invention, FIG. 2 is an explanatory diagram of the control signals in FIG. 1, FIG. 3 is an explanatory diagram of the position detection section in FIG. Figure 5 is the first
FIG. 3 is an explanatory diagram of a display signal generating section in the figure.

Claims (1)

[Claims] 1. In an ultrasonic diagnostic device in which an ultrasonic blood flow meter function is added to an ultrasonic tomographic imaging device, the relative position and angle of a tomographic probe and a blood flow probe can be freely set. a probe holding means capable of detecting the relative position and angle; a control means for controlling the emission pulses for tomographic images and for blood flow by switching them in time series; A display signal generating section that generates a display signal regarding a measurement point of the blood flow meter is provided, and the blood flow velocity at an arbitrary point within the displayed tomographic image is measured and the measurement point of the blood flow velocity is superimposed on the tomographic image. An ultrasonic diagnostic device characterized by: