JP3202124B2 - Ultrasound diagnostic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus capable of constructing a three-dimensional image.

[0002]

2. Description of the Related Art Recently, an ultrasonic diagnostic apparatus for performing three-dimensional scanning has been known. As an example of such an ultrasonic diagnostic apparatus, a technique described in Japanese Patent Application Laid-Open No. 5-23332 is known. The principle of operation will be described with reference to a schematic sectional view of the ultrasonic probe shown in FIG.

In FIG. 5, reference numeral 1 denotes an angle sensor using a piezoelectric gyro for detecting a moving angle of the ultrasonic probe 5 with respect to the surface of the object, and 2 denotes a moving distance of the ultrasonic probe 5 with respect to the surface of the object. This is a distance sensor that emits ultrasonic waves onto the surface of the subject and receives ultrasonic waves reflected by the ultrasonic transducers 3a and 3b. Reference numeral 4 denotes an acoustic medium.

The angle sensor 1 vibrates an internal piezoelectric vibrator by driving piezoelectric magnetism, and when a rotational angular velocity is applied to a central axis of the piezoelectric vibrator, an axis in a direction perpendicular to the original vibration axis. The rotational angular velocity is detected by detecting the Coriolis force generated by the detection electromagnetic force.

The angle sensor 2 makes the acoustic impedance of the acoustic medium 4 largely different from the impedance of the subject, so that most of the ultrasonic waves emitted from the ultrasonic transducer 3a are reflected on the surface of the subject. The Doppler shift frequency of the echo signal of the ultrasonic wave transmitted / received to / from the surface of the subject is measured.

In such a distance sensor 2, when the probe 5 is moved along the surface of the body of the subject while emitting ultrasonic waves from one of the ultrasonic transducers 3a, the ultrasonic waves from the body surface Reflected wave is returned to the ultrasonic transducer 3b after receiving a Doppler shift proportional to its moving speed. The Doppler signal is used to measure the moving distance of the probe 5 by obtaining a voltage proportional to the Doppler shift frequency using, for example, a frequency discriminator provided in the main body of the ultrasonic diagnostic apparatus, and integrating the voltage. can do.

As described above, also in the conventional example described above, the coordinates of the ultrasonic probe on the surface of the subject can be confirmed by using the angle sensor and the distance sensor, and a three-dimensional image can be formed.

[0008]

However, the ultrasonic probe of the conventional ultrasonic diagnostic apparatus requires an angle sensor and a position sensor, and has a problem that the structure of the probe is complicated. Was.

The present invention is to solve such a conventional problem, and it is possible to detect the mutual positional relationship between the tomographic planes and perform three-dimensional display without using a special angle sensor or position sensor. It is an object of the present invention to provide an ultrasonic diagnostic apparatus.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an ultrasonic probe having at least two tomographic planes crossing each other, and information obtained from one of the tomographic planes. It is provided with a means for detecting the spatial movement of the other tomographic plane.

In order to achieve the above object, the present invention also provides an ultrasonic probe having at least two tomographic planes intersecting with each other, and the other based on information obtained from one tomographic plane. The apparatus includes means for detecting a spatial movement of the tomographic plane, and means for forming a three-dimensional image based on information on the spatial movement and a plurality of tomographic images obtained from the tomographic plane.

According to the present invention, in the above structure, the ultrasonic probe is constituted by two ultrasonic probes connected by detachable mechanical means.

[0013]

Therefore, according to the present invention, the position of the ultrasonic probe on the surface of the subject is detected by using the ultrasonic probe having two tomographic planes, so that the spatial positional relationship between the tomographic planes is obtained. Can be detected with high accuracy.

According to the present invention, since the position of the ultrasonic probe on the surface of the subject is detected by using the ultrasonic probe having two tomographic planes, the ultrasonic wave capable of displaying a three-dimensional image is provided. A diagnostic device can be realized.

Further, according to the present invention, the position of the ultrasonic probe on the surface of the subject is detected by arranging the ultrasonic probe detachable by mechanical means so that the two tomographic planes intersect. The spatial positional relationship of the tomographic plane can be detected with high accuracy.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic block diagram showing an ultrasonic diagnostic apparatus according to one embodiment of the present invention. In FIG.
A transmission circuit 11 is connected to the switch 12. The switch 12 receives an input from the three-dimensional display control unit 13 and is connected to the two ultrasonic probes 14 and 15 by a cable. The ultrasonic probe 14 and the ultrasonic probe 15 are arranged so that the tomographic planes intersect each other, and the two ultrasonic probes 14 and 15 constitute an ultrasonic probe. I have.

Signals from the ultrasonic probes 14 and 15 enter a receiving circuit 16 via a cable connecting the switch 12 and the ultrasonic probes 14 and 15, and their outputs enter an A / D converter 17. The output of the A / D converter 17 enters a memory selector 18. The memory selector 18 has another input from the three-dimensional display control unit 13, and the output of the memory selector 18 is divided into three, and the three-dimensional frame memory 19, the movement detection frame memory 20, the movement detection frame memory 21 Connected to. 3D frame memory 1
The input of 9 is the memory selector 18 and the three-dimensional display control unit 13, and the output enters the contour extraction circuit 22. The output of the contour extraction circuit 22 is connected to a three-dimensional DSC 23. The input of the three-dimensional DSC 23 is a contour extraction circuit 22 and the three-dimensional display control unit 13, and the output is connected to the monitor 24. The outputs of the movement detection frame memory 20 and the movement detection frame memory 21 enter the correlation calculator 25. The output of the correlation calculator 25 is connected to a displacement calculation circuit 26, and the output is connected to the three-dimensional display control unit 13.

The above configuration will be described in further detail below together with its operation. The transmission circuit 11 generates a transmission pulse and focuses a transmission beam. The switch 12 selects whether to output a transmission pulse from the transmission circuit 11 to the ultrasonic probe 14 or to the ultrasonic probe 15 according to a signal from the three-dimensional display control unit 13. is there. The ultrasonic probe 14 is a device that performs conversion between an electric signal and an ultrasonic wave. The ultrasonic probe 14 converts an electric pulse wave from the switch 12 into an ultrasonic wave, transmits the ultrasonic wave to the inside of the subject, and outputs an echo as in-vivo information. Is received, converted into an electrical signal, and sent to the receiving circuit 16.
The ultrasonic probe 15 is also similar to the ultrasonic probe 14,
The ultrasonic probe 15 converts an electric pulse wave from the switch 12 into an ultrasonic wave and sends a reception echo to a reception circuit 16. The ultrasonic probe 15 has a tomographic plane with respect to the ultrasonic probe 14. Since they are arranged so as to intersect, the tomographic plane intersecting with the ultrasonic probe 14 is always scanned.

FIGS. 2 and 3 show an example of an ultrasonic probe in which the tomographic planes intersect each other in this embodiment.
FIG. 2 shows that three-dimensional scanning can be performed by arranging the independent ultrasonic probes 14 and 15 using the coupling device 27 so that the tomographic planes scanned by the respective transducers 14a and 15a intersect. This is an example of the ultrasonic probe 28 that has been used. FIG. 3 shows the respective transducers 1 of the ultrasonic probes 14 and 15.
This is an example of an ultrasonic probe 29 configured by combining 4a and 15a so as to be orthogonal. The transducers 14a and 14b of the ultrasonic probe 14 in FIGS. 2 and 3 perform scanning on the xy plane, and the transducers 15a and 15b of the ultrasonic probe 15 perform scanning on the zx plane.

The receiving circuit 16 is a device for delay-combining inputs, aligning phases, performing envelope detection, and outputting the signals. The receiving circuit 16 delay-combines reception echo signals from the ultrasonic probe 14 or the ultrasonic probe 15, The envelope is detected and sent to the A / D converter 17. The A / D converter 17 is a device for converting an analog signal into a digital signal. The A / D converter 17 converts an analog output of the receiving circuit 16 into a digital signal, and sends the digital signal to the memory selector 18. The memory selector 18 is a device for selecting in which memory the input signal is to be stored, and based on the control signal of the three-dimensional display control unit 13, the A / D converter 17
From the three-dimensional frame memory 19 or the movement detection frame memory 20 or the movement detection frame memory 21
To any of

The three-dimensional frame memory 19 is used to move the ultrasonic probes 14 and 15 in parallel by moving the object surface by manual scanning or by moving the tomographic plane up, that is, by moving the ultrasonic probes 14 and 15 so that the tomographic planes cross each other. In order to record each tomographic plane, three-dimensional information (hereinafter referred to as a main tomographic image) of the subject is stored. The movement detection frame memory 20 and the movement detection frame memory 21 each include information from a probe that crosses a tomographic plane with the ultrasonic probe recorded by the three-dimensional frame memory 19 (hereinafter, referred to as a sub-tomographic image).
Is stored.

As an example, the ultrasonic probe 28 shown in FIG. 2 is used, the ultrasonic probe 14 is used for a main tomographic image for forming an image, and the ultrasonic probe 15 performs position detection. The operation in the case of using the sub tomographic image will be described with reference to FIG. In FIG. 4, reference numeral 30 denotes a spherical object simulating an organ in a living body, and the ultrasonic probe 28 is denoted by A,
The echoes of the subject 30 are imaged while moving by manual scanning from above to below in three stages of B and C. Screens 31 to 33 show images of main tomographic images in stages A to C, Screens 34 to 36 are images of secondary tomographic images in stages A to C. It can be seen that the echo of the sphere of the sub tomographic image moves relatively.

The screens 31 to 33 of the main tomographic image obtained from the ultrasonic probe 14 are sent to the three-dimensional frame memory 19, and the screens 34 of the sub tomographic images obtained from the ultrasonic probe 15 are displayed.
To 36 are sent to the movement detection frame memories 20 and 21 alternately.

The movement detection frame memory 20 and the movement detection frame memory 21 store frame information different from each other in the time calendar as described above, and their outputs enter the correlation calculator 25. The correlation calculator 25 stores the movement detection frame memory 20.
And a cross-correlation calculation of 21 and the movement amount and rotation angle between two frames are determined by the motion detection technique of a moving image (for example, IEICE Transactions D-II (1992.9)
The calculation is performed using a technique disclosed on pages 1498 to 1503).

The result calculated by the correlation calculator 25 is sent to a displacement calculator 26. The displacement calculating circuit 26 replaces the detection signal from the correlation calculator 25 with the actual displacement and integrates the signals to calculate position information on the surface of the subject. The result is sent to the three-dimensional display control unit 13. The three-dimensional display control unit 13 generates an appropriate read address to display the three-dimensional information stored in the three-dimensional frame memory 19 on the monitor 24 based on the movement amount calculated by the displacement calculation circuit 25, and performs three-dimensional display. Of the three-dimensional DSC 23 and the control of the switch 12 and the memory selector 18 depending on whether the main tomographic image or the sub tomographic image is obtained.

The information of the main tomographic image recorded in the three-dimensional frame memory 19 is sent to the contour extracting circuit 22 in accordance with the read address generated by the three-dimensional display control unit 13. The contour extraction circuit 22 is a circuit for extracting contour information from the image of the main tomographic image. As such a contour extraction method for three-dimensional display, for example, the Proceedings of the Japanese Society of Ultrasound Medicine (1992.11), p. 539 On page 540.

The three-dimensional DSC 23 renders the image information from the contour extraction circuit 22 on the basis of the three-dimensional coordinates from the three-dimensional display control unit 13, performs scan conversion, and converts this into an analog signal again. Output to the monitor 24 at the timing of the standard television. The monitor 24 is a general monitor that displays an NTSC signal.

In this embodiment, the ultrasonic probe 15 can be used for a main tomographic image and the ultrasonic probe 14 can be used for a sub-tomographic image. Further, in the present embodiment, a linear type ultrasonic probe was combined, but a phased array type, a convex type, a mechanical scanning type, various types of single-plate transducer type, and the like, or a combination of the same type, or It can also be applied when combining different types.

Further, in this embodiment, the case where the shape of the organ or the fetus is displayed according to the intensity of the reflected echo in the subject has been described, but the speed of the blood flow corresponding to the Doppler shift frequency of the reflected echo is described. It can also be applied to a case where it is desired to observe a color Doppler type tomographic image which measures the color and displays it in hue in a wide field of view.

In the above embodiment, a method for forming a three-dimensional image has been described. However, three-dimensional information on a subject can be obtained simply by clarifying the amount of spatial movement between tomographic planes. be able to.

As described above, according to the above embodiment, the ultrasonic probe is arranged so as to obtain the in-vivo information of the two intersecting tomographic planes. Detection can be performed, and three-dimensional image display can be performed.

[0032]

According to the present invention, as is apparent from the above embodiment, the ultrasonic probe is arranged so as to obtain the in-vivo information of the two intersecting tomographic planes. An ultrasonic diagnostic apparatus capable of detecting the mutual positional relationship between surfaces with high accuracy can be realized.

Further, according to the present invention, since the ultrasonic probe is arranged so as to be able to acquire the in-vivo information of two intersecting tomographic planes, a high-precision position detection is performed without a special sensor, and An ultrasonic diagnostic apparatus for displaying an original image can be realized.

Further, according to the present invention, a special sensor is required because two detachable ultrasonic probes are used and the ultrasonic probes are arranged so as to obtain in-vivo information on two crossing planes. Thus, it is possible to realize an ultrasonic diagnostic apparatus capable of detecting the mutual positional relationship between tomographic planes with high accuracy.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention.

FIG. 2 is a perspective view showing an example of the structure of an ultrasonic probe in the apparatus.

FIG. 3 is a perspective view showing another example of the structure of the ultrasonic probe in the apparatus.

FIG. 4 is a schematic diagram showing an operation of the apparatus.

FIG. 5 is a schematic cross-sectional view showing the structure of an ultrasonic probe in a conventional example.

[Explanation of symbols]

 Reference Signs List 11 transmission circuit 12 switch 13 three-dimensional display control 14, 15 ultrasonic probe 16 receiving circuit 17 A / D converter 18 memory selector 19 three-dimensional frame memory 20, 21 movement detection frame memory 22 contour extraction circuit 23 three-dimensional DSC 24 Monitor 25 Correlation calculator 26 Displacement calculation circuit 27 Coupling device 28, 29 Ultrasonic probe 30 Subject 31-36 Screen

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Mitsuo Nishigaki 4-3-1 Tsunashima Higashi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture Inside Matsushita Communication Industrial Co., Ltd. (56) References A) JP-A-56-143148 (JP, A) JP-A-63-46143 (JP, A) JP-A-55-116342 (JP, A) Transactions of the Institute of Electronics, Information and Communication Engineers D-IIII, Vol. J75-D-II, No. 9, September 1992, pp. 1498-1503 (58) Field surveyed (Int.Cl. ⁷ , DB name) A61B 8/00-8/15 G01N 29/00-29/28

Claims (3)

(57) [Claims] An ultrasonic probe having at least two tomographic planes crossing each other, and means for detecting a spatial movement of another tomographic plane based on information obtained from one of the tomographic planes. Ultrasound diagnostic apparatus having. 2. The ultrasonic diagnostic apparatus according to claim 1, wherein a three-dimensional image is formed based on spatial movement information and a plurality of tomographic images obtained from a tomographic plane. 3. An ultrasonic diagnostic apparatus according to claim 1, wherein said ultrasonic probe comprises two ultrasonic probes connected by detachable mechanical means.