JPH0542152A - Ultrasonic endoscope - Google Patents

Abstract

PURPOSE:To make the diameter of the tip constituting part thin, and to obtain a satisfactory ultrasonic image being free from a distortion and a flow by providing a position sensor of a turning member provided in the tip constituting part, in a hand-side operating part. CONSTITUTION:A motor 10 is provided on a hand-side scanning part, its rotation is transferred to an ultrasonic oscillator or a turning mirror 15 through a flexible shaft 2 and while rotating them, an ultrasonic wave is emitted from the oscillator 1 and a body to be examined is rotated and scanned. An ultrasonic image obtained by the rotation and scanning is stored in memory devices 7, 8, and this stored image signal is fetched and subjected to image display. In such a way, a rotational position of the ultrasonic oscillator 1 or the turning mirror 15 is detected by connecting mechanically an encoder 11 to the flexible shaft 2, and whether this rotation pitch is within a prescribed range or not is decided by a repeat deciding circuit 12. Based on a result of this decision, supply of driving power to the ultrasonic oscillator 1 and an input of an image in a line memory 7 are controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic endoscope in which an ultrasonic oscillator is inserted into a body cavity and an ultrasonic image is obtained by sector scanning of an ultrasonic beam.

[0002]

2. Description of the Related Art An apparatus in which an ultrasonic wave oscillator is inserted into a body cavity and an ultrasonic image is obtained by sector scanning of an ultrasonic beam is disclosed in, for example, Japanese Patent Application Laid-Open No. 57-52444. There is. In this device, an ultrasonic oscillator for transmitting and receiving ultrasonic beams is fixedly provided in the insertion tip portion, an ultrasonic reflecting mirror is rotatably provided so as to face the ultrasonic oscillator, and the vicinity of the reflecting mirror is provided. Is provided with a rotating member which rotates integrally with the reflecting mirror, and means for detecting the rotation angle of the rotating member, and an ultrasonic image is projected based on the rotation angle of the reflecting mirror detected by the detecting means. Is configured to.

Further, in Japanese Patent Application Laid-Open No. 2-144046 or Japanese Patent Application Laid-Open No. 2-144047, an ultrasonic endoscope in which an ultrasonic oscillator provided at a tip insertion portion is rotated by using electromagnetic induction. Is disclosed. In these devices, an ultrasonic oscillator, a permanent magnet, a drive coil, and a magnetic body are provided at the tip insertion portion to swing the ultrasonic oscillator, and ultrasonic oscillation is generated based on the current flowing in the drive coil. A sense coil for generating a position signal of the child is provided to detect the position of the ultrasonic oscillator.

[0004]

However, in the apparatus disclosed in Japanese Patent Laid-Open No. 57-52444, since the means for detecting the rotation angle of the reflecting mirror is provided in the tip insertion portion, the tip insertion portion becomes thick. However, there is a drawback that the patient suffers when the ultrasonic endoscope is inserted into the patient's body. Also, since there is a shaft for driving the mirror to rotate in the insertion tip and a signal line for sending an ultrasonic oscillation signal to the oscillator, a 360 ° ultrasonic image can be obtained. There was a drawback that I could not do it. In order to solve this drawback, it is conceivable to dispose the rotation detection part on the proximal operation part, but in the case of such a configuration, it is provided in the flexible tube connecting the insertion tip part and the proximal operation part. Distortion and flow occur in the ultrasonic image due to uneven rotation of the flexible shaft.

On the other hand, JP-A-2-144046, 144
Also in the device described in Japanese Patent No. 047, since the sense coil is provided in the tip insertion portion to detect the rotational position of the ultrasonic oscillator, the structure of the tip insertion portion becomes complicated and the tip is inserted. There is a drawback in that the diameter of the insertion portion becomes large, which causes pain to the patient during insertion. Further, in these devices, the ultrasonic transducer is selectively driven between the N pole and the S pole,
It was constructed to swing like a pendulum of a timepiece and could not be driven to rotate 360 °.

[0006]

In order to solve the above-mentioned problems, the ultrasonic endoscope of the first invention of the present application is insertably and removably inserted into a body cavity and has flexibility at least in an intermediate portion. An ultrasonic oscillator for transmitting and receiving ultrasonic waves provided in the insertion tip of the outer cylinder and an ultrasonic wave emitted from this ultrasonic oscillator are rotated toward the subject in a plane perpendicular to the insertion direction of the insertion tip. Means for scanning, means for detecting an ultrasonic wave reflected by the subject with an ultrasonic oscillator to generate an ultrasonic image signal, and memory means for storing the image signal generated by the image signal generating means, In an ultrasonic endoscope including a display means for extracting the image signal stored in the memory means and displaying the image, a means for detecting the rotational position of the rotary scanning means and a rotational position detection for the rotational position detecting means. Determine the pitch of the signal Means, storage control means for controlling the storage of the image signal in the memory means based on the determination result by the determination means, and drive control means for driving and controlling the ultrasonic oscillator based on the determination result by the determination means. It is characterized by including and.

As described above, in the ultrasonic endoscope of the first invention of the present application, means for detecting the rotation angle of the means for rotationally scanning the ultrasonic waves oscillated from the ultrasonic oscillator is provided in the operating portion on the hand side. Therefore, the size of the insertion tip portion of the ultrasonic endoscope can be reduced. Further, the timing at which the rotational position detection signal of the rotary scanning means is repeated is detected and determined, and if the timing deviates from a predetermined range, the image capturing at this timing is stopped. Therefore, when the rotation unevenness of the flexible shaft occurs, the capturing of the image can be stopped, and the rotation angle detection means of the ultrasonic oscillator is provided in the proximal operation portion to reduce the diameter of the insertion portion, It is possible to prevent distortion and flow of the ultrasonic image.

The ultrasonic endoscope of the second invention of the present application is removably inserted into the body cavity, and at least transmits and receives ultrasonic waves provided in the insertion tip portion of the flexible outer cylinder in the middle portion. An ultrasonic wave oscillator and a rotating mirror rotatably provided at a position facing the ultrasonic wave oscillator are provided, and a magnetic field is applied to one of the facing surfaces of the ultrasonic wave oscillator and the rotating mirror. Is provided and a permanent magnet is arranged on the other surface.

As described above, the ultrasonic endoscope of the second invention of the present application is such that the permanent magnet is provided on one of the facing surfaces of the ultrasonic oscillator disposed at the distal end insertion portion and the rotary mirror provided opposite to the ultrasonic oscillator. Is provided with a coil for generating a magnetic field on the other side, and the rotating mirror is rotated by electromagnetic induction. Therefore,
It is possible to perform 360 ° scanning without blocking the transmission direction of ultrasonic waves with a shaft or a cable. Further, by providing a large number of permanent magnets and a large number of magnetic field generating coils on the surfaces of the ultrasonic oscillator and the rotating mirror that face each other, it is possible to detect the rotational position of the mirror when the rotating magnetic field is stopped. Therefore, the origin information can be obtained without separately providing a sensor, and the diameter of the tip insertion portion can be reduced. Further, in the second invention of the present application, since the flexible shaft is unnecessary, distortion and flow of the image due to the twisting and bending of the flexible shaft do not occur.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a first ultrasonic endoscope of the first invention of the present application.
It is a figure which shows the structure of an Example. The ultrasonic oscillator 1 provided at the insertion tip portion is connected to the reception amplifier 4 and the ultrasonic oscillation drive circuit 5 provided at the near side operation unit via the cable 3 extending in the flexible shaft 2. .. The output of the reception amplifier 4 is connected to the line memory 7 via the A / D converter 6, and is configured to store a digital signal for one line here. The line memory 7 is further connected to the frame memory 8, where 1
After capturing the image signal for the frame, this signal is CR
It is configured to send to T9 and display an ultrasonic image on the display of the CRT 9. A motor 10 and an encoder 11 are mechanically coupled to the flexible shaft 2, drive the motor 10 to rotate the ultrasonic oscillator 1, and indirectly rotate the amount of rotation of the ultrasonic oscillator 1 by the encoder 11. I try to detect it. The output of the encoder 11 is supplied to the repetition determination circuit 12, the transmission timing switching circuit 13, and the reference timing generation circuit 14, respectively, and further, the repetition determination circuit 12
Is supplied to the transmission timing switching circuit 13 and the reference timing generation circuit 14. The reference timing signal generated by the reference timing generation circuit is input to the transmission timing switching circuit 13. The ultrasonic oscillation drive circuit 5 receives the output of the transmission timing switching circuit 13 and transmits the drive signal of the ultrasonic oscillator 1 in synchronization with this. The output of the repeat determination circuit 12 and the output of the transmission timing switching circuit 13 are supplied to the line memory 7, and the transmission timing switching circuit 1
The image signal storage signal is given to the line memory 7 in synchronization with the output of the repeat determination circuit 12 in synchronism with the output of 3.

The operation of the ultrasonic endoscope of the first embodiment having such a configuration is as follows. The rotation of the motor 10 is transmitted to the ultrasonic oscillator 1 via the flexible shaft 2 and drives the ultrasonic oscillator 1 to rotate. An encoder 11 is mechanically connected to the flexible shaft 2, so that the encoder 11 can indirectly monitor the rotation amount of the ultrasonic oscillator 1. Therefore, the output of the encoder 11 reflects the rotational position of the ultrasonic oscillator 1. The output of the encoder 11 is supplied to the repetition determination circuit 12, and here, the encoder 1
The pulse interval of the signal sent from 1 is measured, and it is determined whether this interval is within a predetermined range. On the other hand, the reference timing generation circuit 14 is supplied with the output of the encoder 11 and the output of the repeat determination circuit 12, and here, clocking is started in synchronization with the signal sent from the encoder 11, and a predetermined pulse interval is set. With encoder 1
Generate a pseudo signal of 1. The transmission timing switching circuit 13 includes the output of the encoder 11 and the repeat determination circuit 1.
2 and the output of the reference timing generation circuit 14 are supplied, and when the output of the repeat determination circuit 12 indicates that the output of the encoder 11 is within a predetermined range, the output of the encoder 11 is set to the ultrasonic oscillation drive circuit. When the output of the repeat determination circuit 12 indicates that the output of the encoder 11 is not within the predetermined range, the output of the reference timing generation circuit 14 is output to the ultrasonic oscillation drive circuit 5. Switch the timing. The ultrasonic oscillation drive circuit 5 drives the ultrasonic oscillator 1 via the cable 3 based on the output of the transmission timing switching circuit 13,
The ultrasonic wave is transmitted and received, and the received signal is input again to the reception amplifier 4 via the cable 3 where it is amplified and A /
It is supplied to the line memory 7 as a digital signal via the D converter 6.

On the other hand, the line memory 7 is supplied with the output of the timing switching circuit 13 and the output of the repeat determination circuit 12, and the image is captured in synchronization with the output of the timing switching circuit 13. At this time, when the output of the repeat determination circuit 12 indicates that the pulse interval sent from the encoder 11 is within a predetermined range, the line memory 7 captures an image as usual. On the other hand, if the output of the repeat determination circuit 12 indicates that the pulse interval from the encoder 11 is not within the predetermined range, this signal indicates that the flexible shaft has rotated fast or slow for some reason. Becomes In such a case, if a tomographic image is constructed based on the output of the encoder, the image will be distorted or the image will flow, so new storage of the output of the A / D converter 6 is stopped in the line memory 7, The data of one scan before is retained.

The data stored in the line memory 7 is coordinate-converted and then stored in the frame memory 8. The data is read in synchronization with the TV signal and displayed on the CRT 9 as an image. When the output of the A / D converter 6 is not stored in the line memory 7, the data before one scan remains in the line memory 7, and an image is constructed from this data.

FIG. 2 is a diagram showing a second embodiment of the present invention. In the second embodiment, a mirror 15 is provided in addition to the ultrasonic oscillator 1 at the distal end portion of the ultrasonic endoscope, the flexible shaft 2 is connected to the mirror 15, and the mirror 15 is rotated to rotate the ultrasonic wave. I try to probe. Since the configuration other than this is the same as that of the first embodiment, the reference numerals used in the first embodiment are used and the description of each component is omitted.

In the device of the first embodiment, the rotation of the motor 10 is transmitted to the oscillator 1 via the flexible shaft 2. Therefore, in order to rotate the oscillator 1, a drive signal is sent to the oscillator 1. The transmitting cable 3 and the flexible shaft 2 are rotated together. Therefore, the cable 3 having a small diameter is used to be inserted into the inside of the flexible shaft 2, so that there is a drawback that good rotation characteristics cannot be obtained. On the other hand, in the second embodiment, the oscillator 1 is fixed, and the reflection mirror 15 that reflects the ultrasonic waves transmitted from the oscillator 1 is rotated to perform ultrasonic scanning. With such a configuration, the rotation characteristics of the flexible shaft 2 can be improved, and the restriction on the thickness of the cable 3 is relaxed, so that a cable having a good signal transmission characteristic can be used. .. Further, since the ultrasonic wave generated from the oscillator 1 is applied to the object to be inspected through the mirror 15, an image is constructed without being affected by the disturbance of the near field generated near the oscillator 1. It is possible to obtain a higher quality ultrasonic image.

3 to 7 are diagrams showing the configuration of an embodiment of the second invention of the present application. In the second invention of the present application, the tip forming portion 2
An ultrasonic wave oscillator 22 and a rotating mirror 23 are arranged to face each other in an ultrasonic wave transmission medium 24 housed in 1.
The rotating mirror 23 is installed so as to be rotatable in the output direction of ultrasonic waves. As shown in FIGS. 4 and 6, a plurality of sets of permanent magnets 28 and coils 26 are provided on the peripheral portions of the surfaces of the rotating mirror 23 and the ultrasonic oscillator 22 that face each other. As shown in FIG. 3, a cable 25 for transmitting a transmission / reception signal of ultrasonic waves is provided on the side surface of the oscillator 22 near the hand.
And the coil 2 provided on the ultrasonic wave emitting surface of the oscillator 22.
A cable 27 for sending a rotation signal is connected to the cable 6.

The operation of this embodiment is as follows. The ultrasonic waves radiated / received from the ultrasonic oscillator 22 are transmitted through an ultrasonic transmission medium 24 such as water, reflected by the rotating mirror 23, and then radiated to a subject outside the tip forming unit 21. The ultrasonic waves reflected from the subject are again received by the oscillator 22 via the medium 24 and the rotating mirror 23. Driving power is supplied to the coil 26 provided on the oscillator 22 via the cable 27 to generate a rotating magnetic field. This rotating magnetic field exerts an electromagnetic induction action on a permanent magnet 28 provided corresponding to the coil 26 on the facing surface of the rotating mirror 23, and drives the mirror 23 to rotate. The rotation of the mirror 23 can be controlled by adjusting the drive power applied to the coil 26.

An ultrasonic wave transmission signal is supplied to the oscillator 22 via the cable 25 to emit an ultrasonic wave, and the ultrasonic wave is reflected by the mirror 23 to irradiate the subject. At this time, driving power can be supplied to the coil 26 to rotate the mirror 23, and ultrasonic waves can be rotationally scanned in a direction perpendicular to the outer periphery of the tip forming portion 21. By rotating the mirror 23 once, an image for the entire circumference of the radial scan can be obtained. In this embodiment, since there is no flexible shaft or cable between the rotary mirror 23 and the ultrasonic oscillator 22, a complete omnidirectional operation can be performed.

By increasing the number of coils 26 and the number of permanent magnets 28 provided opposite to them, the position of the mirror 23 can be determined when the rotating magnetic field is stopped, without providing a separate sensor. It is possible to obtain origin information.

[0020]

According to the present invention, since a good ultrasonic image can be obtained without providing a position sensor of an oscillator on the tip forming portion of the ultrasonic endoscope, the tip forming portion has a small diameter. It is possible to reduce the pain of the patient when the endoscope is inserted into the body of the patient.

According to the first aspect of the present invention, it is possible to prevent distortion and flow of the ultrasonic image caused by uneven rotation of the flexible shaft without providing the rotational position detecting means of the rotating member in the distal end forming portion, and thus the distal end is prevented. It is possible to reduce the diameter of the constituent portion and obtain a good ultrasonic image.

In the second invention of the present application, since the flexible shaft is unnecessary, it is possible to obtain an ultrasonic image without distortion or flow. Further, since the rotating mirror is configured to rotate by electromagnetic induction, it is not necessary to interpose a cable between the rotating mirror and the ultrasonic oscillator,
The scanning of the entire circumference of 0 ° can be performed without missing the ultrasonic image. Further, since the origin information can be obtained without providing the sensor coil, it is possible to reduce the diameter of the tip forming portion as in the first aspect of the invention. In addition, since the rotating mirror is rotated by electromagnetic induction, the slip rings of the ultrasonic transmission system and motor drive system, which were required in the past, are no longer needed, and the noise generated by the spark discharge generated in the slip rings can be eliminated. Therefore, a good image can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a first exemplary embodiment of the first invention of the present application.

FIG. 2 is a diagram showing a configuration of a first exemplary embodiment of the first invention of the present application.

FIG. 3 is a diagram showing a configuration of an embodiment of the second invention of the present application.

FIG. 4 is a diagram showing a configuration of a rotary mirror according to an embodiment of the second invention of the present application.

FIG. 5 is a diagram showing a configuration of a rotary mirror according to an embodiment of the second invention of the present application.

FIG. 6 is a diagram showing a configuration of an ultrasonic oscillator according to an example of the second invention of the present application.

FIG. 7 is a diagram showing a configuration of an ultrasonic oscillator according to an example of the second invention of the present application.

[Explanation of symbols]

 1, 22 Ultrasonic oscillator 2 Flexible shaft 3, 25, 27 Cable 4 Amplifier 5 Ultrasonic oscillation drive circuit 6 A / D converter 7 Line memory 8 Frame memory 9 CRT 10 Motor 11 Encoder 12 Repeat determination circuit 13 Timing switching circuit 14 Reference timing generation circuit 15, 23 Rotation mirror 26 Coil 28 Magnet

Claims (2)

[Claims] 1. An ultrasonic oscillator for transmitting and receiving ultrasonic waves, which is inserted into a body cavity so as to be insertable and removable and is provided at least in an insertion tip portion of an outer cylinder having flexibility in an intermediate portion, and from the ultrasonic oscillator. A means for rotationally scanning the emitted ultrasonic waves toward the subject in a plane perpendicular to the insertion direction of the insertion tip, and an ultrasonic image signal obtained by detecting the ultrasonic waves reflected by the subject with an ultrasonic oscillator. An ultrasonic endoscope comprising: a means for generating an image signal; a memory means for storing the image signal generated by the image signal generating means; and a display means for extracting the image signal stored in the memory means and displaying the image. In the above, the means for detecting the rotational position of the rotary scanning means, the means for determining the pitch of the rotational position detection signal of the rotational position detecting means, and the case of the image signal in the memory means based on the determination result by the determining means. An ultrasonic endoscope comprising storage control means for controlling storage and drive control means for driving and controlling the ultrasonic oscillator based on a determination result of the determination means. 2. An ultrasonic wave oscillator for transmitting and receiving an ultrasonic wave, which is inserted into a body cavity so as to be inserted and removed and is provided at least in an insertion tip portion of an outer cylinder having flexibility in an intermediate portion, and the ultrasonic wave oscillator. A rotary mirror rotatably provided at a position facing each other, and a coil for generating a magnetic field is provided on one of the surfaces of the ultrasonic oscillator and the rotary mirror which face each other,
An ultrasonic endoscope in which a permanent magnet is arranged on the other surface.