JPH04187144A - Ultrasonic doppler diagnostic apparatus - Google Patents

Abstract

PURPOSE:To obtain an information on a two-dimensional speed vector at an arbitrary point in space without lowering frame rate by providing two receiving systems and receiving simultaneously reflective signals of a moving reflective body from two directions. CONSTITUTION:Reflective signals from a moving reflective body in a testee are received from two directions, namely, the directions (a) and (b) by means of k pieces of array vibrators on both ends of an ultrasonic probe 2 and receivers 31 and 32 output the signals to vertically crossing detectors 41 and 42 after amplification and at the same time, output receiving beam address signals in the directions (a) and (b) to a speed component operator 6. Moving diameter speed operators 51 and 52 calculate speed components Va and Vb in the moving diameter direction of an ultrasonic reflective wave received from the directions (a) and (b) by a detecting signal and output them to a speed component operator 6. Vx and Vy of two dimensional speed vector of the moving reflective body are calculated by using signals Va and Vb and the receiving beam address signals in the directions (a) and (b), and they are outputted to a operator 7 and an absolute value operator 8 to calculate moving direction theta and moving speed ¦V¦ of the moving reflective body and, after theta and ¦V¦ are converted to digital signals, DSC 9 outputs them to a displaying device 10 and an image is displayed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an ultrasonic Doppler diagnostic device, and in particular, detects two-dimensional velocity information of a motion reflector by emitting ultrasonic waves into a subject and extracts the information. The present invention relates to an ultrasonic Doppler diagnostic device that displays.

[Prior Art] Conventionally, the ultrasonic pulsed Doppler method has been used to measure the velocity of moving parts within a subject, such as organs such as the heart, blood flow in the circulatory system and blood vessels, and movement reflectors such as body fluid flows. The ultrasound Doppler diagnostic device used has been put into practical use.

This ultrasonic Doppler diagnostic device transmits ultrasonic pulses into the subject at a constant repetition rate, and detects the Doppler shift frequency of the reflected wave from the moving reflector within the subject. Detecting speed.

Conventionally, when determining the two-dimensional velocity vector of a motion reflector on a tomographic plane within the subject from velocity information on the ultrasound beam axis in two different directions, the ultrasound beam is transmitted one or more times and this is done. A reflected signal was being received from the direction.

In order to obtain information on the two-dimensional velocity vector of one ultrasound beam line, it was necessary to receive the reflected signals in two directions that differed by a small angle. Collected Papers No. 53, pages 253-25
(described on page 4).

[Problems to be Solved by the Invention] For this reason, 1) the frame rate (the number of frames of an ultrasonic scanning cross section per unit time) has to be lowered, resulting in rapid changes in the movement of the motion reflector within the subject; 2) In addition, there is a time difference of 141 times in the velocity information between the two directions, making it impossible to obtain accurate two-dimensional velocity vector information of the motion reflector inside the subject. there were.

The present invention has been made in view of the above-mentioned conventional problems,
The purpose of this ultrasonic wave is to receive reflected signals from moving reflectors from two directions by providing two receiving systems, thereby obtaining two-dimensional velocity vector information at any point in space without reducing the frame rate. The purpose of the present invention is to provide a Doppler diagnosis 1υi device.

[Means for Solving the Problems] In order to achieve the above objects, the present invention has improved an ultrasonic Doppler diagnostic device.

In other words, in an ultrasonic Doppler diagnostic device that emits ultrasonic waves into the subject at a constant repetition rate, determines the Doppler shift frequency from the reflected signal, and displays the motion state of the motion reflector from this Doppler shift frequency. , a receiving section that sets a receiving beam in two different directions for one ultrasound emission and receives reflected signals from the two directions, and a motion that calculates the velocity component on each ultrasound beam axis from the received signal. a radial velocity calculation unit, a two-dimensional velocity vector calculation unit that calculates a two-dimensional velocity vector in the tomographic plane from velocity components on the two ultrasound beam axes, and a display unit that displays the two-dimensional velocity vector calculation results;
It is characterized by having the following.

Furthermore, in order to simultaneously receive reception signals from two directions, the transducer array provided in the ultrasonic probe is divided into two groups, and two reception systems are provided corresponding to the groups.

The two-dimensional velocity vector calculation unit also includes a velocity component calculation unit that calculates velocity components in the horizontal and vertical directions within the tomographic plane of the motion reflector, a direction calculation unit that calculates the motion direction from the velocity components, and a velocity an absolute value calculator that calculates the absolute value of
It is characterized by having the following.

The speed component calculation unit includes a speed component conversion ROM that converts a radial velocity into a vertical speed component and a horizontal speed component, and a horizontal speed component in two different directions, for each of the horizontal speed component calculation means and the vertical speed component calculation means. The present invention is characterized in that it includes a group of multipliers that perform multiplication of vertical velocity components, a group of adders that add the outputs of the group of multipliers, and a divider that divides the outputs of the group of adders.

[Operations] According to the present invention, two reflected signals from a motion reflector are simultaneously transmitted.
The radial velocity of the motion reflector is determined by orthogonal detection from the received signals from the two directions, and the horizontal velocity components are determined from the radial velocity signals from the two directions. A vertical velocity component is obtained, a direction calculation is performed from this image component signal to determine the direction of motion of the motion reflector, and an absolute value calculation is performed to obtain the motion velocity.

[Example] Next, an ultrasonic Doppler diagnostic apparatus according to the present invention will be described using the drawings.

The principle of the ultrasonic Doppler diagnostic apparatus according to the present invention will be explained using FIGS. 3 and 4.

FIG. 3 shows a conceptual diagram of a two-way reception system, which is a feature of the present invention.

In the figure, in an ultrasonic probe consisting of n transducers (n is an integer), an ultrasonic beam is irradiated in a certain direction, for example, from the transducer of the ultrasonic probe to a moving reflector. Each of the two sets provided at both ends of the sonic probe has an individual (k
is an integer), a receiving beam is set in the a direction and the b direction, and reflected signals from the moving reflector are received simultaneously from each direction.

FIG. 4 is a diagram showing velocity components on the ultrasound beam axis.

In the figure, velocity component vectors Va and Vb in each receiving beam direction of a two-dimensional velocity vector V are determined from received signals from two directions.

With the horizontal direction of the tomographic plane as the X axis and the vertical direction as the y axis, the angles formed by the X axis and the receiving beam axes a and b are respectively θ1. θ
2, the X-axis components of Va and Vb are as shown in the following equations.

In other words, Va - (Vxa, Vya) = (Va11cosθ,, VaIlsinθ1)...
(1) Vb - (Vxb, Vyb)! -(Vb・cosθ21 V b example s s nθ2
)... (2) When the X-axis component and the X-axis component of the two-dimensional velocity vector V of the motion reflector are Vx and Vy, respectively, the two-dimensional velocity vector V is expressed by the following equation.

V'= (Vx, Vy)...
(3) In FIG. 4, 17ta and Vtb are expressed as in the following equation.

Vta=V-Va... (4
)vtb=v−vb +++
(5) Vta and '? 'a are orthogonal, and Vtb,! :V
If b is also orthogonal, the following equation can be obtained.

Va・(v-'Va)=0...(
6) V'b ・(v-'Vb)=O-(7) Above (1
), (2), and (3) into equations (6) and (7), it is expressed as the following equation.

vxa11VX+VyaIIvy -IVaR=0... (6)'vxb
11vx+■yb・vy −1VbR−0・−(7)− 1 From the above equations (6) and (7)′, each component VxSVy of the two-dimensional velocity vector V is expressed as −9= as in the following equation. Ru.

Vx 7 (vyb・lVa 12 −Vya・ ]vb12) / (Vyb φ, Vxa+Vya・Vxb) − (Vb
-sinθ2・Va2 -Va sinθ, -Vb2) /(VbIIsinθ2 conflict vaecosθ10Vb・c
osθ2・va-8inθl)... (8) vy = (Vxb-IVa 12 -VxalVbR) / (vXbIIVya + VXaIIVyb) = (Vb-
cosθ2°V a 2 =va11cosθt ”V b 2)/(vb11
cos θ2・va11 sin θ1+V'a conflict cos θ1
#Vb11sLnθ2)... (9) Here, the values of θ1 and θ2 are determined by setting the receiving beam direction in advance to a predetermined direction, and the values of Va and v
Since b can be measured by the Doppler method, the two-dimensional velocity vector V= (Vx.

Vy) can be obtained.

Next, a preferred embodiment of the ultrasonic Doppler diagnostic apparatus according to the present invention will be described based on the above principle with reference to FIGS. 1 and 2.

FIG. 1 shows a functional block diagram of an ultrasound Doppler diagnostic device.

Device configuration description The device includes a transmitter 1, a probe 2, a receiver 3, an orthogonal detector 4, a radial velocity calculator 5, a velocity component calculator 6,
It is composed of a direction calculator 7, an absolute value calculator 8, a DSC (digital scan converter), and a display 10.

The ultrasonic probe 2 consists of n transducers.

The receiving section 3 includes a receiver (1) 31 and a receiver (2) 32.

The quadrature detector 4 includes a quadrature detector (1) 41 and a quadrature detector (
2) Consists of 42.

The radial velocity calculation unit 5 includes a radial velocity calculation unit (1) 51 and a radial velocity calculation unit (2) 52.

The configuration of the velocity component calculator 6 will be explained with reference to FIG.

Description of Connection Relationship The output of the transmitter 1 is connected to n transducers of the ultrasound probe 2.

One output of the transducer outputs at both ends of the ultrasonic probe 2 is connected to the input of the receiver (1) 31, and the other output is connected to the human power of the receiver (2) 32. .

One output of the receiver (1) 31 is sent to the quadrature detector (1) 4
The a-direction receiving beam address signal of the other output is connected to the a-direction receiving beam address signal input of the velocity component calculator 6, and one output of the receiver (2) 32 is connected to the orthogonal detection The b-direction receive beam address signal of the other output is connected to the b-direction receive beam address signal input of the velocity component calculator 6.

The output of the quadrature detector (1,) 41 is transmitted to the radial velocity calculator (1,
) 51, and the output of the quadrature detector (2) 42 is connected to the input of the radial velocity calculator (2) 52.

The output Va of the radial velocity calculator (1) 51 is connected to the Va large input of the velocity component calculator 6, and the radial velocity calculator (2) 52
The output vb is connected to the vb manual power of the velocity component calculator 6.

The output Vx of the velocity component calculator 6 is connected to the Vx large input of the direction calculator 7 and the Vx large input of the absolute value calculator 8, and the output vy of the velocity component calculator 6 is connected to the vy large input absolute value of the direction calculator 7. The vy large input of the arithmetic unit 8 is connected.

The output θ of the direction calculator 7 is connected to the θ input of the DSC 9.

The output IVI of the absolute value calculator 8 is connected to the IVI input of the DSC 9.

The output of the DSC 9 is input to the display 10.

Description of Device Operation When the transmission signal output from the transmitter 1 is input to the transducer of the ultrasonic probe 13, an ultrasonic beam is transmitted from the transducer to the subject.

The reflected signal from the motion reflector inside the subject is sent to the ultrasound probe 2.
Reflected waves are received from two directions, the a-direction and the b-direction, by array transducers at each end of the oscillator.

For example, a reflected signal received from the direction a is converted into an electric signal by a vibrator and input to the receiver (1,) 31, and at the same time, a reflected signal received from the direction b (no. 6 is also converted to an electric signal by a vibrator). The signal is converted into a signal and input to the receiver (2) 32.

The receiver (1,) 31 amplifies the input received signal, and then
It outputs to the quadrature detector (1) 41, and at the same time generates an a-direction reception beam address signal and outputs it to the velocity component calculator 6.

Similarly, the receiver (2) 32 amplifies the input reception signal and outputs it to the quadrature detector (2) 42, and at the same time generates a b-direction reception beam address signal and outputs it to the velocity component calculator 6.
Output to.

The quadrature detector (1) 41 orthogonally detects the signal from the receiver (1) 31, and the detected signal is output to the radial velocity calculator (1) 51.

Similarly, the quadrature detector (2) 42 orthogonally detects the signal from the receiver (2) 32, and the detected signal is sent to the radial velocity calculator (2).
52.

The radial velocity calculator (1) 51 calculates the radial velocity component Va of the ultrasonic anti-Ω/J wave received from the a direction from the input detection signal, and calculates the velocity component of the obtained signal. Output to device 6.

The radial velocity calculator (2) 52 calculates the radial velocity component vb of the ultrasonic reflection signal received from direction b from the input detection signal and sends the obtained signal to the velocity component calculator 6. Output.

The velocity component calculator 6 calculates the X-axis component Vx and Y-axis component vy of the two-dimensional velocity vector of the motion reflector using the manually inputted Va and vb multiplied signals, the a-direction receiving beam address signal, and the b-direction receiving beam address signal. The calculated value is output to the direction calculator 7 and the absolute value calculator 8, respectively.

The direction calculator 7 calculates the arctangent of the input signal from the input Vx multiplied signal and vy multiplied signal to determine the motion direction θ of the motion reflector.
Calculate. The obtained signal is output to the DSC9.

The absolute value calculator 8 calculates the root force of the sum of squares of the input f≦ from the input Vx multiplied signal vy (No. 4) to calculate the motion velocity IVI of the motion reflector. signal is DSC
9 is output.

The DSC 9 converts the input θ and IVI into digital signals and outputs the digital signals to the display 10.

The display 10 displays an image of the movement direction and movement speed of the movement reflector based on the input display signal.

FIG. 2 shows a functional block diagram of the velocity component calculator 6 included in the ultrasonic Doppler diagnostic apparatus of FIG. 1, which is a feature of the present invention.

Configuration description of speed component calculator The speed component calculator 6 includes a speed component conversion ROM (],) 61
, velocity component conversion ROM (2) 62, and multiplier 611
to 615, multipliers 621 to 625, and adder 61
6 to 617, adders 626 to 627, and divider 6
18.628.

= 15 - Explanation of connection relationship of velocity component calculator Input Va is connected to the input of velocity component conversion ROM (1) 61 and the first and second inputs of multiplier 611, and input v
b is connected to the input of the velocity component conversion ROM (2) 62 and the first and second inputs of the multiplier 621.

The input a-direction received beam address signal is converted into velocity component R
The input direction receiving beam address signal is connected to the input of the OM (1) 6], and the input direction receiving beam address signal is connected to the input of the velocity component conversion ROM (2) 62.
connected to the input of

The output va2 of multiplier 611 is connected to a first input of multiplier 612 and a second input of multiplier 622.

The output Vb2 of multiplier 621 is connected to a second input of multiplier 613 and a second input of multiplier 623.

Velocity component conversion ROM (1) 61 vertical component output Va◆
sin θ1 is the first input of the multiplier 613 and the multiplier 61
5 and the second input of the multiplier 624, and the horizontal component output Va-cos-16-θ1 is connected to the first input of the multiplier 614 and the first input of the multiplier 623.
and a first input of multiplier 625.

Velocity component conversion ROM (2) 62 vertical component output vb-
6inθ2 is the second input of multiplier 612 and multiplier 61
4 and the second input of the multiplier 625, and the water i11 component output Vb-cos θ2 is connected to the second input of the multiplier 615, the first input of the multiplier 622, and the multiplier 624.
connected to the first human power source.

It is connected to the multiplication output Va2·Vb-8inθ2 of the multiplier 612.

The multiplication output Va-8inθ1·Vb2 of the multiplier 613 is connected to the subtraction input of the adder 616.

Addition output A of adder 616 is connected to the divide input of divider 618.

The multiplication output of multiplier 614 is connected to a first addition input of adder 617.

The multiplication output of multiplier 615 is connected to a second addition input of adder 617.

Addition output B of adder 617 is connected to a division input of divider 618.

The division output Vx of the divider 618 is connected to the Vx large input of the direction calculator 7 and the Vx large input of the absolute value calculator 8 in FIG.

The multiplication output of multiplier 622 is connected to the addition input of adder 626.

The multiplication output of multiplier 623 is connected to the subtraction input of adder 626.

The addition output C of adder 626 is connected to the divide input of divider 628.

Multiplier 6249 multiplication output is connected to a first addition input of adder 627.

The multiplication output of multiplier 625 is connected to a second addition input of adder 627.

The addition output of adder 627 is connected to the division input of divider 628.

The division output vy of the divider 628 is connected to the vy large input of the direction calculator 7 and the vy large input of the absolute value calculator 8 in FIG.

Explanation of operation of velocity component calculator When the input signal va and the input a-direction reception beam address signal are input to the velocity component conversion ROM (1) 61, this signal is used as an address signal and is converted by the conversion coefficient stored in advance in the ROM. The input signal is converted, the vertical component and horizontal component of the motion velocity Va are calculated, and the vertical component signal (V
a-sin θ1) is output to the first input of the multiplier 613, the first input of the multiplier 615, and the second input of the multiplier 624. Further, the horizontal component signal (Va-Cos θ■) is output to the first input of the multiplier 614, the first input of the multiplier 623, and the first input of the multiplier 625.

When the input signal vb and the direction receiving beam address signal are input to the velocity component conversion ROM (2) 62, the input signal is converted using the conversion coefficients stored in advance in the ROM using this signal as an address signal. The vertical component signal (Vb-sin θ2) is output to the second input of multiplier 612, the second input of multiplier 614, and the second input of multiplier 625. In addition, the horizontal component signal (Vb-CoSθ2)
is output to a second input of multiplier 615 , a first input of multiplier 622 , and a first input of multiplier 624 .

In addition, the input Va is input to the first and second inputs of the multiplier 611, and the multiplication output (Va2) is the first input of the multiplier 612.
and the second input of multiplier 622.

In addition, the input vb is input to the first and second inputs of the multiplier 621, and the multiplication output (Vb2) is the second input of the multiplier 613.
input and output to the second input of multiplier 623.

The calculation multiplier 612 for the X-axis component Vx outputs the multiplication result (Va2-Vb-s inθ2) of the signals of the first input and the second input to the adder 61.
It is output to the addition input of 6.

Further, the multiplier 613 outputs the multiplication result (Vb2·va-8inθ1) of the first input signal and the second input signal to the adder 61
It is output to the subtraction input of 6.

The adder 616 adds and subtracts the addition input signal and the subtraction input signal, and the divider 61
8 as the divided signal.

The multiplier 614 outputs the multiplication result (■a-cos θ1 .■b-8in θ2) of the signals of the first human power and the second human power to the addition input of the adder 617.

Moreover, the multiplier 615 multiplies the signals of the first human power and the second human power (Va-5inθ1・vb・cosθ2)
is output to the addition input of adder 617.

The adder 617 outputs the addition result B (represented by the denominator equation of equation (8) above) obtained by adding the first addition input signal and the second addition input signal to the division input of the divider 618. be done.

The divider 618 divides the input signal A to be divided by the input signal B to be divided and outputs the result as the X-axis component Vx (expressed by equation (8) above) of the moving speed of the reflector.

The calculation multiplier 622 for the Y-axis component vy calculates the multiplication result (
Va2·vb−cos θ2) is output to the addition input of the adder 626.

The multiplier 623 multiplies the first input and the second input (
Vb2·va-cos θ1) is output to the subtraction input of the adder 626.

The adder 626 outputs the addition/subtraction result C between the addition input signal and the subtraction manual signal (represented by the numerator of equation (9) above) to the divider input of the divider 628 .

The multiplier 624 outputs the multiplication result (Va-sin θ1 ・Vb-cos θ2) of the first input and the second input to the adder 6
It is output to the addition input of 27.

The multiplier 625 outputs the multiplication result of the first input and the second input (Va-cos θ1 ・Vb-8 effect θ2) to the adder 62
It is output to the addition input of 7.

The adder 62b outputs the addition result D of the first addition input signal and the second addition input signal (represented by the denominator equation of equation (9) above) to the division input of the divider 628. Ru.

The divider 628 divides the signal C to be divided by the input signal to be divided and outputs the result as the Y-axis component Vy (expressed by the above equation (9)) of the motion velocity of the motion reflector.

By the above calculation, the X-axis component Vx and the Y-axis component vy of the motion velocity V of the motion reflector were obtained. These Vx and vy are output to a direction calculator 7 and an absolute value calculator 8, respectively.
The direction calculator 7 obtains the moving direction θ of the moving reflector, and the absolute value calculator 8 obtains the magnitude of the moving speed of the moving reflector.

[Effects of the Invention] As described above, according to the present invention, since the motion vector of the motion reflector is obtained by simultaneously receiving ultrasound reflection signals from two force directions, it is possible to obtain the motion vector of the motion reflector without reducing the frame rate. It is possible to accurately detect blood flow velocity vectors within the tomographic plane.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram of an ultrasonic Doppler diagnostic device according to the present invention, FIG. 2 is a functional block diagram of a velocity component calculator shown in FIG. 1, and FIG. 3 is a functional block diagram of an ultrasonic Doppler diagnostic device according to the present invention. A diagram showing the two-way reception method of ultrasonic reflection (No. 5) to show the principle of the ultrasonic Doppler diagnostic device. It is a vector diagram showing the components. 1... Transmitter 2... Ultrasonic probe 3... Receiving unit 4... Orthogonal detection unit 5... Radial velocity calculation unit 6... Velocity Component calculator 7...Direction calculator 8...Absolute value calculator 9...DSC 10...Display unit 31...Receiver (1) 32...Receiver (2) 41...・ Quadrature detector (1) 42 ... Quadrature detector (2) 51 ... Radial velocity calculator (1) 52 ... Radial velocity calculator (2) 61 ... Speed component conversion ROM ( ],)62...
・Speed component conversion ROM (2) 611 to 615, 62
1 to 625... Multipliers 616 to 617, 626 to 6
27... Adder 618.628... Divider

Claims (4)

[Claims] (1) Ultrasonic Doppler diagnostic equipment that emits ultrasonic waves into the subject at a constant repetition rate, determines the Doppler shift frequency from the reflected signal, and displays the motion state of the motion reflector from this Doppler shift frequency. , a receiving section that sets a receiving beam in two different directions for one ultrasound emission and receives reflected signals from the two directions, and calculates the velocity component on each ultrasound beam axis from the received signal. a radial velocity calculation unit; a two-dimensional velocity vector calculation unit that calculates a two-dimensional velocity vector in the tomographic plane from velocity components on the two ultrasound beam axes; a display unit that displays the two-dimensional velocity vector calculation results; An ultrasonic Doppler diagnostic device comprising: (2) In the ultrasonic Doppler diagnostic apparatus according to claim 1, in order to simultaneously receive reception signals from two directions, an array of ultrasonic transducers provided in the ultrasonic probe is used.
An ultrasonic Doppler diagnostic apparatus characterized by being divided into two groups and having two receiving systems corresponding to the groups. (3) In the ultrasonic Doppler diagnostic apparatus according to claim 1, the two-dimensional velocity vector calculation unit is a velocity component calculation unit that calculates horizontal and vertical velocity components in the tomographic plane of the motion reflector. 1. An ultrasonic Doppler diagnostic device comprising: a direction calculator that calculates a motion direction from a velocity component; and an absolute value calculator that calculates an absolute value of the velocity. (4) In the ultrasonic Doppler diagnostic apparatus according to claim 3, the velocity component calculator calculates the radial velocity from the vertical velocity component and the horizontal velocity component for each of the horizontal velocity component computing means and the vertical velocity component computing means. Speed component conversion RO to convert into speed component
M, a group of multipliers that multiply horizontal velocity components and vertical velocity components in two different directions, a group of adders that add the outputs of the group of multipliers, and a divider that divides the outputs of the group of adders. An ultrasonic Doppler diagnostic device comprising: