JPH07395A - Catheter type ultrasonic probe - Google Patents

Abstract

PURPOSE:To provide a catheter type ultrasonic probe which is flexiible and fine in diameter and enables high production efficiency. CONSTITUTION:This catheter type ultrasonic probe is provided with a tube 1 and an acoustic head section 2. A piezoelectric vibrator 3 transmitting and receiving an ultrasonic beam, an ultrasonic reflector 4 rotatably arranged in front of the piezoelectric vibrator 3, a permanent magnet 5 rotatively driven by the magnetic field formed by a stator provided outside and rotating the ultrasonic reflector 4, and a liquid acoustic medium 6 sealed in a void section between at least the ultrasonic reflector 4 and piezoelectric vibrator 3 are stored in a case 7 to form the acoustic head section 2. A cable 8 connected to the piezoelectric vibrator 3 is inserted into the tube 1, and the acoustic head section 2 is connected to the tip of the tube 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter type ultrasonic probe.

[0002]

2. Description of the Related Art FIG. 7 shows a conventional example of a catheter type ultrasonic probe used for obtaining an ultrasonic tomographic image of a predetermined site by inserting it into a blood vessel or body cavity of a human body. In this conventional example, a piezoelectric vibrator 3 driven by a signal from a device body 15 outside the body is fixed to the distal end portion of the flexible tube 1, and a reflecting surface 4a has an elliptical shape behind it. An ultrasonic reflector 4 having a shape obtained by cutting a cylindrical body is arranged.
In FIG. 7, reference numeral 8 denotes a cable connecting the device body 15 and the piezoelectric vibrator 3.

The ultrasonic reflector 4 is rotatably supported by a bearing 16 in order to perform radial scanning of the ultrasonic beam from the piezoelectric vibrator 3.
The rotary power of the motor 17 on the side of the flexible shaft 1
It is transmitted to the ultrasonic reflector 4 via 8.

However, in the above-mentioned conventional example, the flexible shaft 18 requires a predetermined rigidity for power transmission, and therefore the rigidity of the entire body also becomes high, so that it cannot be inserted into a deep part of the human body. If there is a possibility that the blood vessel may be damaged, or if the catheter is inserted into a tortuous blood vessel and the curvature of the catheter is small, the flexible shaft 18 cannot rotate smoothly due to the friction with the inner wall of the tube 1. It has a drawback that the image dripping is caused by the uneven rotation of the sound wave reflector 4.

In order to solve such a drawback, there has been proposed a structure in which a motor 17 is formed in the tip portion of the tube 1 to scan an ultrasonic beam, but the motor 17 having a rotor, a stator and the like as its constituent elements is proposed. In order to arrange the inside of the tube 1, a constant volume is required, so that there is a drawback that the outer diameter of the ultrasonic probe becomes large.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks, and provides a catheter type ultrasonic probe which is flexible, has a small diameter, and has high manufacturing efficiency. To aim.

[0007]

According to the present invention, the above object corresponds to an embodiment, as shown in FIG.
And an acoustic head portion 2, the acoustic head portion 2 being
The piezoelectric vibrator 3 for transmitting and receiving ultrasonic beams, the ultrasonic reflector 4 rotatably arranged in front of the piezoelectric vibrator 3, and a magnetic field formed by a stator provided outside are driven to rotate by the magnetic field. Permanent magnet 5 for rotating the sound wave reflector 4
And at least a liquid acoustic medium 6 sealed in a space between the ultrasonic reflector 4 and the piezoelectric vibrator 3 are housed in a case 7, and the acoustic head unit 2 is made of a piezoelectric material. This is achieved by inserting a cable 8 connected to the transducer 3 into the tube 1 to provide a catheter type ultrasonic probe joined to the tip of the tube 1.

[0008]

The catheter type ultrasonic probe according to the present invention is formed by fixing the acoustic head portion 2 in which the constituent members such as the piezoelectric vibrator 3 are incorporated in advance to the tip of the tube 1. As a result, it is not necessary to assemble parts into the tip of the small-diameter tube 1 and the manufacturing efficiency is improved.

Further, the ultrasonic reflector 4 forming the scan beam is driven by a stator provided outside, and the diameter and the size of the ultrasonic reflector 4 can be made smaller and smaller than in the case where all the motors 17 are formed in the tube 1. Planned.

In the invention according to claim 2, the probe has an insertion hole 10 through which the guide wire 9 is inserted through the outer wall portion.
It is possible to insert the probe using the guide wire 9.

Further, in the invention of claim 3, the rotation axis of the ultrasonic reflector 4 is arranged at a position eccentric with respect to the central axis of the acoustic head portion 2. Due to the eccentricity of the rotation center, the distance between the beam transmission position and the acoustic window changes, and it is possible to recognize the exact position and orientation of the probe from the change in the image based on this change.

In the invention according to claim 4, a piezoelectric vibrator 3 driven by a magnetic field from an external stator is swingably held at the tip of the tube 1, and a sector in front of the probe is used. It is possible to obtain an image.

In the invention according to claim 5, the piezoelectric vibrator 3 and the like are incorporated in the acoustic head portion 2, and the probe is formed by fixing the acoustic head portion 2 to the tip of the tube 1. The production efficiency can be improved.

Further, in the invention of claim 6, an extra length absorbing space 13 for absorbing an extra length of the cable 8 is provided at a connecting portion of the cable 8 to the piezoelectric oscillator 3, so that the piezoelectric oscillator 3 swings. The cable 8 is prevented from being damaged during the dynamic operation.

In the invention according to claim 7, the distance between the acoustic transmission / reception surface 3a of the piezoelectric vibrator 3 and the acoustic window is formed so as to differ depending on the swing angle of the piezoelectric vibrator 3. As a result, the distance between the beam transmission position and the acoustic window changes, and it is possible to recognize the exact position and orientation of the probe from the change in the image based on this change.

Further, in the invention according to claim 8, the probe has an insertion hole 10 through which the guide wire 9 is inserted through the outer wall portion.
And can be guided to a predetermined portion by the guide wire 9.

In the invention of claim 9, the oscillating surface of the piezoelectric vibrator 3 intersects with the guide wire 9 so that a received image including the image of the guide wire 9 can be obtained, and the received image is searched. It is possible to accurately recognize the position and posture of the tentacle.

In the invention according to claim 11, the joint portion between the acoustic head portion 2 and the tube 1 is flexible, and the acoustic head portion 2 is necked with respect to the central axis of the tube 1. Swing displacement is possible. As a result, the probe can be deformed according to the curvature of the blood vessel or the like, and the probe can be inserted deeper.

Further, in the invention according to claim 12,
The tube 1 is made of a synthetic resin material mixed with a material having an excellent X-ray absorption ability, and the position of the probe can be easily grasped.

According to the thirteenth aspect of the present invention, a marker 14 having an ultrasonic wave propagation characteristic different from that of other portions is formed in a part of the acoustic window for transmitting and receiving ultrasonic waves. Marker 1
4 indicates the position on the image by reflecting, for example, an ultrasonic wave, and the observer can detect the insertion posture of the probe based on this.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings. The catheter type ultrasonic probe according to the present invention, as shown in FIG.
And the acoustic head portion 2 fixed to the tip of the tube 1.
Composed of and.

The acoustic head portion 2 is inserted into the case 7 in which the front end opening of the housing cylinder 12 is closed by the cap member 11, the permanent magnet 5, the ultrasonic reflector 4 and the tube 1 housed in the case 7. And a piezoelectric vibrator 3 connected to a cable 8.

The storage cylinder 12 and the cap member 11 which form the case 7 are formed of, for example, a urethane-based synthetic resin material in which blood is less likely to coagulate, and the cap member 11 and the storage cylinder 12 are joined by an epoxy adhesive. And the like. Further, since the storage cylinder 12 serves as an acoustic window when transmitting and receiving ultrasonic waves, it is desirable that the storage cylinder 12 be formed as thin as possible.

On the other hand, the permanent magnet 5 constitutes a motor 17 in cooperation with a stator arranged outside the human body, and is rotatably supported by a rotary shaft 11a projecting from the rear wall surface of the cap member 11, It is rotationally driven by the magnetic field formed by the stator.

The ultrasonic reflector 4 is formed by cutting a cylindrical body so that the reflecting surface 4a has an elliptical shape.
For example, the back wall of the reflecting surface 4a is bonded to the permanent magnet 5 so as to be integrated with the permanent magnet 5, and is rotated with the rotation of the permanent magnet 5.

The ultrasonic reflector 4 is arranged with the reflecting surface 4a facing rearward, and the piezoelectric vibrator 3 is arranged with the acoustic transmitting / receiving surface 3a facing the reflecting surface 4a of the ultrasonic reflecting body 4. . The piezoelectric vibrator 3 according to this embodiment includes an acoustic transmitting / receiving surface 3
It is a focus type vibrator in which a has a curvature so as to focus on a predetermined part in the body, and it is desirable that the backing material for preventing ultrasonic waves from wrapping around to the back surface at the time of transmission is a terminal formation surface. Is located in.

In addition, the rear surface of the piezoelectric vibrator 3 is provided with a housing cylinder 1
The inside of the storage cylinder 12 is hermetically sealed by being joined to the sealing flange 19 projecting from the inner wall of 2, and the acoustic impedance of the storage cylinder 12 is substantially equal to that of the human body, and A material that does not affect the human body even if it leaks into the human body, that is, an acoustic medium 6 such as water or physiological saline is enclosed.

The acoustic head unit 2 constructed as described above
Are sub-assembled in advance and fixed to the tip of the tube 1 to form an ultrasonic probe. The acoustic head portion 2 can be fixed to the tube 1 by a known means such as adhesion or welding.

Further, the tube 1 is provided with X of BaBr 2 or the like.
If a material that absorbs rays is mixed, it becomes possible to accurately know the position of the catheter during X-ray observation, which is convenient for diagnosis.

Further, as shown in FIG. 2, by forming an insertion hole 10 for inserting the guide wire 9 in the distal end of the tube 1 and a part or all of the acoustic head, the catheter can be more accurately positioned at a predetermined site. You can guide.

Further, as shown in FIG. 3, the cross-sectional shape of the tip of the tube 1 is made into an edge shape which becomes thinner toward the tip, and a taper portion 20 is formed at a corresponding portion of the acoustic head portion 2. When they are connected in a fitted state, the acoustic head portion 2 can be displaced in a swinging manner with respect to the central axis of the tube 1, so that the catheter can be extended along the curved portion of the blood vessel. Can be inserted easily.

Therefore, the catheter type ultrasonic probe in this embodiment is first inserted into a desired site in the body, and then, when a stator (stator) outside the body is driven, an area including the catheter is reached. Due to the magnetic field generated, the permanent magnet 5 and the ultrasonic reflector 4 inside the catheter rotate around the central axis, and a radial scan beam is emitted to a predetermined site.

In this case, when a marker 14 for reflecting ultrasonic waves is formed on the inner wall of the housing cylinder 12 which serves as an acoustic window, from the reflection echo of the window appearing in the received signal of the piezoelectric vibrator 3,
It becomes possible to know the insertion posture of the catheter in the blood vessel, such as the rotation angle of the ultrasonic reflector 4, and the position of the obtained tomographic image can be specified in more detail.

The marker 14 can be formed by arranging a special material in the storage cylinder 12, but as shown in FIG. 4A, the inner wall of the storage cylinder 12 has a uniform cross-sectional shape. It can also be realized by changing parts. Further, the same effect is obtained as shown in FIG.
The rotation center 4b of the ultrasonic reflector 4 is set to the central axis 1 of the storage cylinder 12.
It is also possible to make it eccentric by δ with respect to 2a.

FIG. 5 shows a second embodiment of the present invention. In the description of the present embodiment, the same configurations as those of the above-described embodiment will be designated by the same reference numerals in the drawings and will not be described. This example shows a modification suitable for sector-scanning ultrasonic waves forward from the insertion site of the catheter.
A vibrator accommodating recess 21 is provided at the tip of the tube 1.

As shown in FIG. 6, the vibrator accommodating recess 21 is formed to have a diameter slightly larger than the outer diameter of the piezoelectric vibrator 3, and is a hinge support groove opened outward on the inner wall surface facing the vibrator. 22 is provided.

On the other hand, as shown in FIG. 5A, the piezoelectric vibrator 3 is provided with a cylindrical hinge portion 23 on the side wall and a terminal 24 on the back side of the sound transmitting / receiving surface 3 a, and is provided inside the tube 1. The inserted cable 8 is connected to the terminal 24.

As will be described later, in order to reduce the load on the cable 8 when the piezoelectric vibrator 3 swings, the cable 8 is piezo-electric in a state where an extra length is generated in the vicinity of the joint part of the piezoelectric vibrator 3. The tube 1 is connected to the vibrator 3, and further, in order to absorb the extra length portion, an extra length absorbing space 13 is formed in the tube 1 by extending the vibrator housing recess 21 rearward.

The piezoelectric vibrator 3 is held at a predetermined position by fitting the hinge portion 23 into the hinge support groove 22 of the tube 1, and the cap member 11 is attached to the front open end of the tube 1. The cap member 11 has a hinge presser 25 on the back surface, and in a state of being joined to the tip of the tube 1, cooperates with the wall surface of the hinge support groove 22 to sandwich the hinge portion 23 of the piezoelectric vibrator 3, The piezoelectric vibrator 3 is held swingably.

The extra length absorbing space 13 of the tube 1
A sealing material 26 is filled in the gap between the wall surface of the cable 8 and the cable 8, and an acoustic medium 6 such as physiological saline is sealed in the gap between the piezoelectric vibrator 3 and the cap member 11.

Therefore, in this embodiment, when the external stator (stator) is driven after inserting the catheter into a desired portion of the body, the piezoelectric vibrator 3 having the permanent magnets 5 swings and moves forward. Sector beam is emitted.

In this embodiment also, if the marker 14 is formed on the cap member 11 which will be the acoustic window,
From the reflection echo of the window appearing in the reception signal of the piezoelectric vibrator 3, it becomes possible to know the insertion posture of the catheter in the blood vessel, such as the swing angle of the ultrasonic reflector 4, and the position of the obtained tomographic image can be better understood. It can be specified in detail.

Further, in the above description, the respective constituent members such as the piezoelectric vibrator 3 are directly incorporated in the tip of the tube 1. However, as shown in the above-mentioned first embodiment, these respective constituent members are incorporated. It is also possible to manufacture by sub-assembling in the case 7 in advance and joining to the tip of the tube 1.

When the ultrasonic beam is sector-scanned forward, if the position of the insertion hole 10 is set so that the guide wire 9 is arranged in the sector area, the guide wire 9 is moved. The position can be captured in the ultrasonic image.

[0045]

As is apparent from the above description, according to the present invention, the catheter can be miniaturized in order to rotationally drive the ultrasonic reflector or the piezoelectric vibrator by the magnetic field of the external stator. it can.

Further, in the case where each component is incorporated in the acoustic head part in advance, the manufacturing efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a view showing a modified example of FIG. 1, in which (a) is a sectional view,
(B) is a BB line sectional view of (a).

FIG. 3 is a diagram showing still another modification example of FIG. 1.

FIG. 4 is a diagram showing a modification of the acoustic head unit.

5A and 5B are views showing a second embodiment of the present invention, in which FIG. 5A is a sectional view and FIG. 5B is a perspective view showing a piezoelectric vibrator.

FIG. 6 is an exploded perspective view of FIG.

FIG. 7 is a diagram showing a conventional example.

[Explanation of symbols]

 1 Tube 2 Acoustic Head Part 3 Piezoelectric Vibrator 3a Acoustic Transmission / Reception Surface 4 Ultrasonic Reflector 5 Permanent Magnet 6 Acoustic Medium 7 Case 8 Cable 9 Guide Wire 10 Insertion Hole 11 Cap Member 12 Storage Cylinder 13 Extra Length Absorption Space 14 Marker

Front page continuation (72) Inventor Kenji Kawabe 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Fujitsu Limited

Claims (13)

[Claims] 1. A piezoelectric vibrator (3) for transmitting and receiving an ultrasonic beam, comprising: a tube (1) and an acoustic head portion (2), wherein the acoustic head portion (2) is a piezoelectric oscillator (3). ), A permanent magnet (5) that is rotatably driven by a magnetic field formed by an ultrasonic reflector (4) and a stator provided outside to rotate the ultrasonic reflector (4). ), And at least a liquid acoustic medium (6) enclosed in a space between the ultrasonic reflector (4) and the piezoelectric vibrator (3) are housed in a case (7), and The acoustic head part (2) is a catheter type ultrasonic wave joined to the tip of the tube (1) by inserting a cable (8) connected to the piezoelectric vibrator (3) into the tube (1). Probe. 2. A catheter type ultrasonic probe according to claim 1, wherein an insertion hole (10) for inserting a guide wire (9) is formed in the outer wall portion, and the guide wire (9) can guide the guide wire to a predetermined portion. . 3. The catheter type ultrasonic probe according to claim 1, wherein the rotation axis of the ultrasonic reflector (4) is arranged at a position eccentric with respect to the central axis of the acoustic head portion (2). Child. 4. A tube (1) through which a cable (8) is inserted, and a tube (1) connected to the cable (8), with the sound transmitting / receiving surface (3a) facing the open end of the tube (1). The piezoelectric vibrator (3) housed in the tip of the body is swingable, and the piezoelectric vibrator (3) is driven by a magnetic field formed by an externally provided stator so that the piezoelectric vibrator (3) is placed on the central axis of the tube (1). A permanent magnet (5) that swings against the cap, a cap member (11) that closes the open end of the tube (1), and a space between the piezoelectric vibrator (3) and the cap member (11). A catheter type ultrasonic probe having a liquid acoustic medium (6) to be enclosed. 5. A piezoelectric vibration which is housed in the housing cylinder (12) so that the sound transmitting / receiving surface (3a) faces the open end of the housing cylinder (12) and is swingably housed in the tip of the housing cylinder (12). A child (3), and a permanent magnet (5) driven by a magnetic field formed by an externally provided stator to swing the piezoelectric vibrator (3) with respect to the central axis of the housing cylinder (12), A cap member (11) for closing the open end of the housing cylinder (12), and a liquid acoustic medium (6) sealed in a space between the piezoelectric vibrator (3) and the cap member (11). The acoustic head part (2) is formed by the acoustic head part (2), and the cable (8) connected to the piezoelectric vibrator (3) is inserted into the tube (1) to form the tube (1). Catheter type ultrasonic probe joined to the tip of the. 6. The extra length absorbing space (13) for absorbing the extra length of the cable (8) is provided at a connection portion of the cable (8) to the piezoelectric vibrator (3). Catheter type ultrasonic probe. 7. A sound transmitting / receiving surface (3) of the piezoelectric vibrator (3).
The catheter type ultrasonic probe according to claim 4, 5 or 6, wherein the distance between a) and the acoustic window differs depending on the swing angle of the piezoelectric vibrator (3). 8. An insertion hole (10) through which a guide wire (9) is inserted is formed in an outer wall portion, and the guide wire (9) can guide to a predetermined portion.
The described catheter-type ultrasonic probe. 9. The catheter according to claim 8, wherein the oscillating surface of the piezoelectric vibrator (3) intersects with the guide wire (9), and a received image including an image of the guide wire (9) can be obtained. Type ultrasonic probe. 10. The catheter type ultrasonic probe according to claim 1, wherein the acoustic head portion (2) is fixed to the tip of the tube (1) by adhesion. 11. A joint portion between the acoustic head portion (2) and the tube (1) is flexible, and the acoustic head portion (2) is arranged with respect to a central axis of the tube (1). The catheter type ultrasonic probe according to claim 10, which is capable of swinging displacement. 12. The tube (1) is formed of a synthetic resin material mixed with a material having an excellent X-ray absorbing ability. 10 or 11
The described catheter-type ultrasonic probe. 13. A marker (14) having a different ultrasonic wave propagation characteristic from other parts is formed in a part of an acoustic window for transmitting and receiving ultrasonic waves, and an insertion posture can be detected from an image by the marker (14). Claims 1, 2, 3, 4, 5, 6, 7,
The catheter type ultrasonic probe according to 8, 9, 10, 11 or 12.