JPH0499566A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To measure all the blood flow speeds in a blood vessel by preparing a two-dimensional array vibrator and executing the focus control not only in the azimuth direction but also in the lens direction, so that an ultrasonic scan can be executed so as to cover the whole area of the diagnostic object part. CONSTITUTION:When an ultrasonic scan of (k) pieces of vibrators 2 in the X direction is executed, an X direction tomography image is displayed on a monitor 13. As for the display of this X direction tomography image, in a state that the tomography image containing a blood vessel is displayed on the monitor 13, a range gate mark MR is displayed by displaying an M marker from a keyboard 5 and executing an operation so as to designate blood vessel width on this M marker. Subsequently, by executing an ultrasonic scan of (l) pieces of vibrators 2 in the Y direction. a Y direction tomography image is displayed on the monitor 13. As far as it is concerned, since a pattern in the Y direction and an aperture of an ultrasonic beam are controlled so as to coincide with overall width of the blood vessel diameter by the control of a controller 4 executed from the keyboard 5, a sample volume mark M is displayed on overall, width of the blood vessel diameter.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention detects, for example, a Doppler signal from a desired part of a subject, reconstructs and monitors an ultrasound image such as a blood flow image. The present invention relates to an ultrasonic diagnostic device displayed on the screen.

(Conventional technology) Ultrasonic waves are transmitted and received to and from the subject to create a tomographic image (
Ultrasonic diagnostic apparatuses are known that have a B-mode scanning function for obtaining a B-mode image (B-mode image) and a Doppler mode scanning function for obtaining a Doppler image such as a blood flow image. In this way, an ultrasound diagnostic apparatus equipped with B-mode and Doppler mode scanning functions alternately performs B-mode scanning and Doppler-mode scanning in synchronization with the rate signal fr, as shown in the timing chart in FIG. B-mode images and Doppler images are obtained.

The Doppler mode scanning function of such an ultrasonic diagnostic apparatus is used to measure the velocity of a moving body such as blood flow. FIG. 9 shows the principle of measuring blood flow velocity. When an ultrasonic pulse fc is incident from the ultrasound probe 1 at an angle θ to the blood flow 15 in the blood vessel 14 moving at a velocity V, , this incident ultrasonic pulse fc is shifted by the frequency fd due to the Doppler effect and is reflected in the incident direction. The Doppler shift frequency fd at this time is 4
It is shown as follows.

f d=2vc o sθ・fC/C C: Sound speed of ultrasonic pulse Therefore, as is clear from the above equation, COSθ.

Since fc and C are known, the blood flow velocity V can be obtained by calculating fd as shown in the following equation.

v=C・fd/2vcO8θef The blood flow velocity V is displayed on a monitor and used for diagnosis.

FIG. 6 shows a probe used in such an ultrasonic diagnostic device, and this probe 1 has a plurality of transducers 2.
are arranged in strips in the X direction (azimuth direction), and are comprised of a so-called one-dimensional array vibrator.

The surfaces of the plurality of vibrators 2 are covered with acoustic lenses 16. FIGS. 7(a) and 7(b) show the delay characteristics of such a probe and the beamform of the ultrasonic wave, respectively. By applying different amounts of delay to a plurality of vibrators 2 in the X direction using a well-known delay means, it is possible to obtain, for example, a total delay characteristic as shown in the figure. Furthermore, based on such delay characteristics, it is possible to emit an ultrasonic beam 17 whose focus is controlled in the X direction as shown in FIG. 7(b). Note that the beamform in the Y direction is fixed and uniquely determined by the acoustic lens 16.

Figures 8(a) and 8(b) show an X-direction tomographic image and a Y-direction tomographic image obtained by transmitting and receiving ultrasonic waves to and from the blood vessels of a subject using an ultrasound diagnostic device equipped with such a probe. It shows the image. Blood vessel 14 in the X-direction tomogram
The range gate mark MR is set to match the diameter of the range gate mark MR. Further, as is clear from the Y-direction tomographic image orthogonal to the X-direction tomographic image, the ultrasound beam 17 is radiated across the blood vessel 14 . The width of the ultrasonic beam 17 at this time is the value determined by the acoustic lens 16 as described above.

(Problem to be solved by the invention) By the way, in the conventional ultrasonic diagnostic apparatus, the 8th FjgJ (b
), in the Y direction (lens direction) tomographic image, the width of the ultrasound beam 17 is too narrow relative to the diameter of the blood vessel 14, making it impossible to measure all blood flow velocities within the blood vessel 14. The problem is that it can't be done. For example, when measuring blood flow velocity, it is clinically important to capture the maximum flow velocity VMAX in the blood vessel 14, but when the entire width of the blood vessel diameter is not covered by the ultrasound beam as in the past, the maximum flow velocity V There may be cases where MAX cannot be accurately captured. Alternatively, it may be possible to cover the entire width of the diameter of the blood vessel 14 by shifting the width of the ultrasound beam 17, but in this case, the operation will take time.

Furthermore, in this case, it becomes impossible to capture the flow velocity distribution within the blood vessel all at once.

The present invention has been made in response to the above-mentioned problems.
It is an object of the present invention to provide an ultrasonic diagnostic apparatus that can cover the entire width of a blood vessel diameter, which is a diagnosis target site, with an ultrasonic beam in one operation.

[Configuration of the Invention (Means for Solving the Problem) In order to achieve the above object, the present invention transmits and receives ultrasonic waves to and from a subject from a probe in which a plurality of transducers are regularly arranged. In an ultrasonic diagnostic device that reconstructs an ultrasonic image based on detected echo signals and displays it on a monitor, a probe in which a plurality of transducers are regularly arranged in each of the two-dimensional directions of the X direction and the Y direction. means for transmitting and receiving ultrasound from the probe to set a sample volume mark at a desired region in the displayed ultrasound image; The present invention is characterized by comprising means for controlling the focus of one of the vibrators.

(Function) During Doppler mode scanning, a two-dimensional array transducer in which multiple transducers are arranged in the two-dimensional direction of the By performing focus control, the ultrasound beam width is controlled to cover the entire width of the blood vessel diameter. This makes it possible to measure all blood flow velocities within the blood vessel, and to accurately capture the maximum flow velocity VMAX no matter where in the blood vessel it is located in a single operation.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the ultrasonic diagnostic apparatus of the present invention, in which 1 is a probe, and as shown in FIG. 2, a plurality of transducers 2 are arranged in the X direction (azimuth direction).

X,,X3. m pieces are arranged like..., and
The direction (lens direction) is also Y, , Y2. Y3. It consists of a structure in which n pieces are arranged as shown in FIG. These X-directions and the plurality of transducers 2 arranged in a matrix in the X-direction are configured to be electronically focus-controlled independently in each direction to form a beamform.

FIGS. 3(a) and 3(b) explain this situation, and show the X direction X1. X2. X3. ... give different delay amounts to the plurality of transducers 2 in the Y direction Y, , Y
2. Y3. By giving different amounts of delay to the plurality of vibrators 2, it is possible to obtain the overall delay characteristic as shown in FIG. 3(a). Further, based on such delay characteristics, it is possible to form a beamform whose focus is controlled not only in the X direction but also in the X direction as shown in FIG. 3(b).

3 is a switch, and a probe 1 is made up of mxn transducers 2.
, the purpose is to select an arbitrary (+XJ) transducer 2 in the X and X directions necessary for ultrasonic scanning the blood vessel 14, which is the diagnosis target site, and this selection is based on the control of the controller described later. It will be carried out. 4 is the controller and CP
It is composed of a central processing unit (U), which is in charge of overall control operations, and performs necessary control based on input data from the keyboard 5.

6 is a pulser which is synchronized with the rate signal and outputs probe 1's (4
This is for supplying high-voltage pulses to drive the vibrators 2 of XA) Ch, and drives each vibrator 2 so as to give a preset delay amount in the transmission delay circuit 7. 8 is a preamplifier that amplifies the echo signal including the Doppler signal obtained by transmitting and receiving ultrasound from the probe 1 to the subject;
This amplified signal is given a delay amount equivalent to that of the transmission delay circuit 7 by a reception delay circuit 9 over iXj - Ch, and then phased and added by an addition circuit 10. Subsequently, the output of the adder circuit 10 is branched into two paths, one to the B-mode line La for reconstructing the B-mode image;
The other one is supplied to the Doppler model line LD for reconstructing the Doppler image. In the B mode line La, only the Doppler signal component (blood flow velocity) is detected by the envelope detection circuit 11, and after the scanning method is converted by the DSC (digital scan converter) 12, the B mode is displayed on the TV monitor 13. A statue is displayed.

Further, in the Doppler mode line LD, a Doppler component is detected by a phase detection circuit 18, and only a desired signal of this Doppler component is extracted by a frequency analyzer 19, so that a blood flow image is displayed on the TV monitor 13.

Next, the operation of this embodiment will be explained.

During Doppler mode scanning, the controller 4 controls the probe 1 in which mxn transducers 2 are arranged in a matrix in the X and X directions as shown in FIG. 1 necessary to perform an ultrasound scan of the blood vessel of the subject, which is the diagnosis target area, by using switch 3.
X1) number of oscillators 2 are selected. Next, the selected vibrators 2 in the X direction (azimuth direction) and the vibrators 2 in the X direction (azimuth direction) are
Electronic focus control is performed on each transducer 2 in the scanning direction (in the scanning direction) according to the delay characteristics shown in FIG. Sends and receives sound wave beams.

First, when an ultrasonic scan of the transducer 2 on the long side in the X direction (azimuth direction) is performed, an X direction tomographic image as shown in FIG. 4(a) is displayed on the monitor 13. The display of this X-direction tomographic image is carried out by using a well-known means such as a trackball from the keyboard 5 while the tomographic image including blood vessels is being displayed on the monitor 13.
A range gate mark MR is displayed by displaying a marker and specifying the blood vessel width on this M marker. Next, one vibrator 2 in the Y direction (scan direction)
By performing the ultrasonic scan, a Y-direction tomographic image as shown in FIG. 4(b) is displayed on the monitor 13. This is done by controlling the Y-direction pattern and aperture of the ultrasonic beam to match the full width of the blood vessel diameter under control of the controller 4 in accordance with input operations performed in advance from the keyboard 5, thereby forming the sample volume mark M5. is displayed across the entire width of the vessel diameter.

This especially allows probe 1 to be moved in the Y direction (scan direction).
The transducer 2 is also focus-controlled, and the width of the ultrasound beam can be varied and narrowed down so that it always matches the diameter of the blood vessel, which is the region to be diagnosed.

Therefore, when diagnosing blood vessels, it is possible to perform an ultrasound scan that covers the entire width of the blood vessel diameter with an ultrasound beam in one operation, making it possible to easily measure all blood flow velocities within the blood vessel. .

As a result, the maximum flow velocity VMAX can be accurately determined in a single operation regardless of where it is located in the blood vessel, thereby improving operability. In other words, as before,
Maximum velocity VM by shifting the ultrasonic beam width in the Y direction several times
Since complicated operations such as capturing the AX are not required, wasted operation time can be saved.

When Doppler mode scanning is completed, B mode scanning is performed at the next timing of the rate signal, and a B mode image is displayed on the TV monitor 13. Thereafter, these Doppler mode scans and B mode scans will be performed alternately at the timing of the rate signal, and blood flow images will be obtained only during Doppler mode scans.

As a modification of this embodiment, the ultrasound beam width, which can be varied in the Y direction (scanning direction), can be set in advance in several stages depending on the diameter of the blood vessel or the area to be measured, which is the region to be diagnosed. For example, Ri, M.

By setting three stages such as S and providing corresponding switches, you can easily set the required ultrasonic beam width by simply selecting the desired switch, without having to operate a trackball each time. Can be set.

The present invention also provides two sets of transducer rows 2X arranged orthogonally to each other, as shown in FIG.

The present invention can also be applied to so-called orthogonal coaxial pipe lane technology, which is configured to be able to capture tomographic images in two orthogonal directions at the same time by preparing 2Y and performing ultrasound scans on two sets at the same time.

In this way, according to this embodiment, the width of the ultrasound beam is narrowed down so that it always matches the diameter of the blood vessel that is the diagnostic target region during Doppler mode scanning, so it does not affect the B-mode scanning in any way. Able to achieve purpose.

For example, it is not preferable to vary the width of the ultrasound beam as described above in order to improve resolution during B-mode scanning, but since such an operation is performed only during Doppler mode scanning, there is no problem.

[Effects of the Invention] As described above, according to the present invention, a two-dimensional array transducer is prepared and focus control is performed not only in the azimuth direction but also in the lens direction, thereby making it possible to cover the entire area of the diagnosis target region. Since a sound wave scan can be performed, all blood flow velocities within blood vessels can be measured.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the ultrasonic diagnostic device of the present invention, FIG. 2 is a perspective view showing a probe used in the device of this embodiment, and FIGS. 3(a) and 3(b) are FIG. Delay characteristics and ultrasonic radiation pattern diagram of the probe, Fig. 4(a),
(b) shows the X-direction tomographic image and the Y-direction tomographic image obtained in this example.
directional tomographic image, FIG. 5 is a schematic diagram showing a modification of this embodiment,
FIG. 6 is a perspective view showing a probe used in a conventional device;
Figures 7(a) and (b) are delay characteristics and ultrasonic radiation pattern diagrams of the probe in Figure 6, and Figures 8(a) and (b).
) is an X-direction tomographic image and a Y-direction tomographic image obtained by a conventional device, Fig. 9 is an explanatory diagram of the measurement principle of blood flow velocity, and Fig. 10 is an explanation of drive timing for performing B-mode and Doppler mode scanning. It is a diagram. 1... Probe, 2... Vibrator, 4... Controller, 5... Keyboard, 14... Blood vessel, 17...
・Ultrasonic beam, M...Range gate mark, M5...Sample volume mark. Figure y Figure (b)

Claims (3)

[Claims] (1) Ultrasonic waves are transmitted and received from a probe with multiple transducers arranged regularly to and from the subject, and an ultrasound image is reconstructed based on the detected echo signals and displayed on a monitor. A sonic diagnostic device includes a probe in which a plurality of transducers are regularly arranged in two-dimensional directions (X direction and Y direction), and transmits and receives ultrasound waves from the probe to a desired region of the displayed ultrasound image. Ultrasonic diagnosis characterized by comprising means for setting a sample volume mark, and means for controlling the focus of one of the transducers in the X and Y directions so that the sample volume mark matches the dimensions of a desired region. Device. (2) The ultrasonic diagnostic apparatus according to claim 1, wherein the ultrasonic diagnostic apparatus detects a Doppler signal from a subject, reconstructs an ultrasonic image based on the detected Doppler signal, and displays the reconstructed ultrasonic image on a monitor. (3) The ultrasonic diagnostic apparatus according to claim 1, wherein the focus of the transducer in one direction is controlled so that the sample volume mark matches the diameter of the blood vessel of the subject.