JPH024342A - Ultrasonic diagnosing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention transmits an ultrasound beam to a living body, receives an echo signal from the living body, and obtains an ultrasound tomographic image based on the received echo signal for diagnosis. The present invention relates to an ultrasonic diagnostic apparatus that can perform

2. Description of the Related Art Conventionally, this type of ultrasonic diagnostic apparatus rotates, oscillates, or moves a support body on which a plurality of piezoelectric vibrators are mounted, and during this period, an ultrasonic beam is directed toward a living body. A known configuration is known in which an echo signal is transmitted from a living body and an echo signal from a living body is received, and an ultrasonic tomographic image is obtained based on the received signal. Among such conventional ultrasonic diagnostic apparatuses, see FIG. 3 for an ultrasonic diagnostic apparatus using a mechanical scanning type ultrasonic probe such as that described in Japanese Patent Application Laid-Open No. 61-58648. I will explain while doing so.

As shown in FIG. 3, on the ultrasonic probe 50 side, three piezoelectric vibrators 51 a and 5 having the same center frequency
1 b and 51 c are attached at a predetermined angle (120°) to a rotor 52 that is a support, and the rotor 52 is rotatably supported by a rotating shaft 54 within an acoustic window 53 made of synthetic resin. The acoustic window 53 is filled with a sound wave propagation medium 56 such as degassed water. The rotating shaft 54 is linked to a drive unit 57 via a power transmission mechanism 58 such as a belt or gears. On the side of the ultrasound diagnostic apparatus main body 59, a transmitter 60. Receiver 61, display 62, transmitter 60 and receiver 6
1 and connected to the ultrasonic probe 50 through a signal line 63 (abbreviated as one line in the figure).

Next, the operation of the above conventional example will be explained.

The drive unit 57 connects the rotor 52 via the power transmission mechanism 58.
and rotate the piezoelectric vibrators 51a, 51b, 51C,
A transmitter 60 applies a transmission signal corresponding to the center frequency to predetermined piezoelectric vibrators 51 a, 51 b, and 51 C via a selection switch 64 and a signal line 63.

This transmission signal causes the piezoelectric vibrators 51a, 51b, 51C to
transmits an ultrasound beam 66 to a living body 65. living body 65
The echo signal from the tissue is transmitted by the piezoelectric vibrator 51a.

51b and 51c, the signal is converted into a received signal, and is sent to the receiver 61 via a signal line 63 and a selection switch 64, where it is amplified and scan-converted and sent to the TV.
The image is displayed on the display 62 as an ultrasonic tomographic image.

Problems to be Solved by the Invention However, in the conventional ultrasonic diagnostic apparatus described above, when transmitting and receiving ultrasonic waves with different center frequencies, the center frequencies of the piezoelectric vibrators 51a, 51b, and 51C of the ultrasonic probe 50 must be changed. There must be. That is, a plurality of ultrasound probes 50 equipped with piezoelectric transducers 51a, 51b, and 51C having different center frequencies are prepared in advance, and these ultrasound probes 50 are exchanged and connected to the ultrasound diagnostic apparatus main body 59. I had to use it. For this reason, especially the ultrasonic probe 50
In an ultrasound diagnostic device that is inserted into the body or body cavity for diagnosis, the ultrasound probe 50 must be taken in and out of the body or body cavity every time the center frequency is changed, which causes pain to the patient. The present invention solves the problems of the prior art, such as the problem of μ, and can be used without replacing the ultrasonic probe. It is possible to obtain ultrasound tomographic images with multiple center frequencies, improving diagnostic efficiency and accuracy, and when using the ultrasound probe by inserting it into the body or body cavity. The object of the present invention is to provide an ultrasonic diagnostic device that can alleviate patient pain.

Means for Solving the Problems The technical solution of the present invention for achieving the above object is as follows:
an ultrasonic probe that transmits and receives ultrasound by rotating, oscillating, linearly or curvedly moving at least one piezoelectric vibrator; The piezoelectric vibrator includes a plurality of transmit signal generators that generate signals, and a plurality of receive signal processors that are selectively connected to the piezoelectric vibrator and process received signals having different center frequencies, the piezoelectric vibrator, This system is configured to be able to perform transmission and reception signal processing for a plurality of sets of center frequencies by combining a transmission signal generator and a reception signal processor.

For production The effects of the above technical means are as follows.

In other words, by combining the center frequency of the pressure transducer with the center frequencies of the transmitting signal generator and receiving signal processor, it is possible to generate ultrasound tomographic images with multiple center frequencies without replacing the ultrasound probe. Obtainable.

EXAMPLE μ Below, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a partially cutaway configuration diagram showing an ultrasonic diagnostic apparatus according to an embodiment of the present invention.

As shown in FIG. 1, the ultrasonic diagnostic apparatus of the present invention is roughly divided into a mechanical scanning type ultrasonic probe 1 and an ultrasonic diagnostic apparatus main body 2. The ultrasonic probe 1 is used for transvaginal diagnosis, for example, and is used by being inserted into the vagina, and first and second piezoelectric vibrators 1a and 1b are attached to a rotor 2 back to back, First and second piezoelectric vibrators 1a
and 1b have different center frequencies, e.g. 5MHz and 7.5
MHz. The rotor 2 is rotatably supported by a rotating shaft 5 within an acoustic window 4 made of synthetic resin provided on the front side of the housing 3, and as the rotor 2 rotates, the piezoelectric vibrators 1a and 1b are successively opposed to each other. . A motor 6 is supported inside the rear part of the housing 3, and the rotating shaft 5 is rotated by a drive shaft 7 directly connected to the motor 6. An encoder 8 is connected to the motor 7. Inside the housing 3, an oil seal 9 is interposed on the outer periphery of the drive shaft 7 to partition the rotor 6 side and the motor 7 side, and an ultrasonic propagation medium 10 such as water or oil is sealed on the acoustic window 4 side. ing. Transmission and reception of signals between the first and second piezoelectric vibrators 1a and 1b and the ultrasound diagnostic apparatus main body 2 is performed via a rotary transformer 11 provided around the rotating shaft 5 and a signal line 12. The encoder 8 is directly connected to the drive shaft 7 of the motor 6, and transmits the rotational state of the motor 6 to the ultrasound diagnostic apparatus main body 2.
The position b is transmitted to the ultrasound diagnostic apparatus main body 2 and used as control information such as ultrasound transmission and reception timing. In addition, motor 6
The drive line, the output line of the encoder 8, the power supply line, etc. are not shown.

To explain the ultrasonic diagnostic apparatus 2, the transmitter 13 (a first transmit signal generator 13a that generates a transmit signal with a center frequency of 51'viHz, and a second transmitter that generates a transmit signal with a center frequency of 7.5 MHz) Which transmission signal is to be transmitted to the ultrasound probe 1 is selected by a transmission selection switch 15 controlled by a control signal from a controller 14. , which transmission signal from the transmission signal generators 13a and 13b is to be transmitted to the ultrasound probe 1 is not limited to the transmission selection switch 15;
N, OFF causes the transmission signal generator 13a or 13
It is also possible to selectively operate only one of b.

The transmission signal is selectively controlled by a vibrator selection switch 16 which is controlled by a control signal from a controller 140, and is applied to a desired piezoelectric vibrator 1a or 1b. The receiver 17 has two center frequencies of 5 MHz and 7.5 MHz, respectively.
It is comprised of first and second received signal processors 17a and 17b that can process two received signals. Specifically, these received signal processors 17a and 17b include amplifiers, detectors,
It consists of various filters. Note that the various filters may include so-called dynamic filters whose bandwidth and center frequency change over time. The first and second reception signal processors 17a and 17b convert the echo signals from the living body received by the piezoelectric vibrator 1a or 1b into the vibrator selection switch 16 and the controller 14.
The reception selection switch 18 is controlled by a control signal. The signal received by the reception signal processor 17a or 17b is processed by an A/D converter, a D/A converter,
The image is sent to a scan converter 19 composed of a frame memory or the like, converted into a TV system, and then displayed on a display 20 as an ultrasonic tomographic image.

In the configuration above μ, the operation below μ will be explained.

By driving the motor 6, the rotor 2 and the first and second piezoelectric vibrators la and lb are connected to each other via the drive shaft 7, e.g.
Rotate in one direction at rpm. On the other hand, by the switching operation of the transmission selection switch 15 under the control of the controller 14, the first or second transmission signal generator 13a or the first
Transmit the signal from 3b to the transducer selection switch 16, signal line 1
2 and the rotary transformer 11 to the first or second piezoelectric vibrator 1a or 1b. This transmission signal causes the first or second piezoelectric vibrator 1a,
Alternatively, 1b transmits an ultrasound beam to a living body. The echo signal from the tissue of the living body is received by the first or second piezoelectric sensor 1a or 1b and converted into a reception signal, which is then sent to the rotary transformer 11, the signal line 12, the transducer selection switch 16, and the reception selection switch. 1st through 18;
Or the second received signal processor 17a or 17b
sent to. The signal processed by the first or second reception signal processor 17a1 or 17b is converted by the scan converter 19 and then displayed on the display 20 as an ultrasonic tomographic image.

As described above, the controller 14 controls the transmission selection switch 15,
Piezoelectric vibrator 1a by controlling vibrator selection switch 16 and reception selection switch 18.

1b, transmitting signal generators 13a, 13b, and receiving signal processors 17a, 17b are used in combination, but L piezoelectric vibrators (L>l), M transmitting signal generators, and N receiving signal processors are used. group A (1×A×LXMXN
) center frequency transmission/reception signal processing becomes possible. In this embodiment, the piezoelectric vibrator 1a.

1b, two transmission signal generators 13a and 13b, and two reception signal processors 17a and 17b are used, and each has two degrees of freedom, so transmission and reception signal processing for eight sets of center frequencies is performed. It becomes possible.

However, considering the center frequency and bandwidth of the transmitting signal generators 13a and 13b, the center frequency and bandwidth of the piezoelectric vibrators 1a and lb, and the center frequency and bandwidth of the receiving signal processors 17a and 17b, the piezoelectric vibrator 1a .

1b center frequency and the received signal processors 17a, 17
The center frequency and bandwidth of b are linked, and therefore, in practice, it is preferable to obtain ultrasonic tomographic images having four sets of center frequencies and use them for diagnosis.

Table 1 below shows 5 MHz (f s ) and 7.5 MHz
The transmission signal generator 13a has two types of center frequencies: z (f 2 ).

13b, 5MHz (ft) and 7.5MHz (fz
)02 types of piezoelectric vibrators 1a, l with the same center frequency
four types of center frequencies 5 MHz and 6 MHz experimentally obtained using
, 7.5 ■h, and this shows the change in 5.
MHz, 6 MHz, 6.5 MHz,
Ultrasonic tomographic images with four types of center frequencies of 7.5 MHz can be obtained.

Below is a blank table 1. The above table 1 shows the center frequency of the transmitting signal generators 13a, 13b, the piezoelectric vibrators 1a, lb, and the receiving signal processor 17.
The center frequency of a and 17b is 5 MHz, 7.5 M
The Hz is set to be exactly the same, but in practice there is no problem even if there is a slight difference.

Figure 2 is an explanatory diagram showing how to obtain a center frequency between the piezoelectric vibrators, such as 1b, and a transmission signal generator, 13a, which have different center frequencies, and the solid line indicates the center frequency of 5MHz (fl). The spectrum of the transmission signal generator 13a, the broken line is the center frequency of 7.5 MHz (f
2) shows the spectrum of the piezoelectric vibrator 1b. The center frequency f3 of the ultrasound tomographic image when both are combined is f
Located between l and fz. Considering the effect of attenuation based on frequency dependence in the living body, the combination to obtain the center frequency f3 is such that the center frequency of the piezoelectric vibrator is higher than the center frequency of the transmission signal generator. is preferred.

In the above embodiment, the case where the rotor 2, etc. is rotated at 60 rpm to transmit and receive ultrasonic waves has been explained. Alternatively, the piezoelectric vibrator may be moved linearly or curvilinearly on a curved line having a predetermined curvature to transmit and receive ultrasonic waves. In addition, the number of piezoelectric vibrators, transmission signal generators, and reception signal processors may be three or more, and the number of piezoelectric vibrators may be one. By using a combination of a pressure transducer, multiple transmitting signal generators with different center frequencies, and multiple receiving signal processors with different center frequencies, the This makes it possible to obtain ultrasound tomographic images with a center frequency of , that is, different information, without converting the ultrasound probe.
An ultrasonic tomographic image with optimal resolution and examination depth can be obtained, and diagnostic efficiency and accuracy can be improved. In addition, when the ultrasound probe is inserted into the body or body cavity, there is no need to replace the ultrasound probe as described above, which greatly reduces the patient's pain. be able to.

[Brief explanation of the drawing]

Fig. 1 shows an ultrasonic diagnostic apparatus according to a first embodiment of the present invention, with a partially cutaway configuration diagram, Fig. 2 is an explanatory diagram of center frequency change, and Fig. 3 shows a conventional ultrasonic diagnostic apparatus. FIG. 2 is a partially cut away configuration diagram. la, lb - piezoelectric vibrator, 2... rotor, 6... motor, 13a, 13b - transmission signal generator, 14.
Controller, 15... Transmission selection switch, 16... Vibrator selection switch, 17a, 17b Reception signal processor,
181. Reception selection switch. 4MAt steam

Claims (3)

[Claims] (1) An ultrasonic probe that transmits and receives ultrasonic waves by rotating, oscillating, linearly or curvilinearly moving at least one piezoelectric vibrator, and a center frequency probe that is selectively connected to the piezoelectric vibrator and a plurality of transmission signal generators that generate transmission signals with different center frequencies; and a plurality of reception signal processors that are selectively connected to the piezoelectric vibrator and process reception signals with different center frequencies; An ultrasonic diagnostic apparatus characterized in that it is configured to perform transmission and reception signal processing of a plurality of sets of center frequencies by combining a transducer, a transmission signal generator, and a reception signal processor. (2) The ultrasonic diagnosis according to claim 1, wherein a plurality of piezoelectric vibrators having different center frequencies are used, and a combination of these piezoelectric vibrators and a plurality of reception signal processors having the same center frequency is selected. Device. (3) The ultrasonic diagnostic apparatus according to claim 1 or 2, wherein the combination is selected such that the center frequency of the piezoelectric vibrator is higher than the center frequency of the transmission signal from the transmission signal generator.