JP3313455B2 - Catheter type ultrasound probe - Google Patents

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 which is used to obtain an ultrasonic tomographic image or the like of a predetermined portion by being inserted into a blood vessel or a body cavity in 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 a distal end portion of a flexible tube 1, and a reflecting surface 4 a has an elliptical shape behind the piezoelectric vibrator 3. An ultrasonic reflector 4 having a shape obtained by cutting a cylindrical body is arranged.
In FIG. 7, reference numeral 8 denotes a cable for connecting the device main body 15 and the piezoelectric vibrator 3.

In order to radially scan the ultrasonic beam from the piezoelectric vibrator 3, the ultrasonic reflector 4 is rotatably supported by a bearing 16.
The rotational power of the motor 17 is supplied to the flexible shaft 1
8 to the ultrasonic reflector 4.

However, in the above-mentioned conventional example, the flexible shaft 18 requires a predetermined rigidity for power transmission, so that the overall rigidity is also high, so that the flexible shaft 18 cannot be inserted deep into the human body. When the catheter is inserted into a meandering blood vessel or the like and the curvature of the catheter is small, the flexible shaft 18 cannot be smoothly rotated due to friction with the inner wall of the tube 1. There is a drawback that the image is dripped due to 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 provided in the distal end portion of the tube 1 to scan an ultrasonic beam. In order to dispose the ultrasonic probe in the tube 1, a certain volume is required, and therefore, there is a disadvantage 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 has as its object to provide a catheter-type ultrasonic probe which is flexible, has a small diameter, and has a high production efficiency. Aim.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided a tube 1 as shown in FIG.
And an acoustic head unit 2, wherein the acoustic head unit 2 comprises:
The piezoelectric vibrator 3 for transmitting and receiving the ultrasonic beam, the ultrasonic reflector 4 rotatably disposed in front of the piezoelectric vibrator 3, and the ultrasonic vibrator driven by a magnetic field formed by a stator provided outside the ultrasonic vibrator 3 Permanent magnet 5 for rotating sound wave reflector 4
And a liquid acoustic medium 6 sealed at least in a gap between the ultrasonic reflector 4 and the piezoelectric vibrator 3, which is formed in a case 7. This is achieved by inserting a cable 8 connected to the vibrator 3 into the tube 1 to provide a catheter-type ultrasonic probe joined to the distal end of the tube 1.

[0008]

The catheter type ultrasonic probe according to the present invention is formed by fixing the acoustic head section 2 in which components 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 incorporate components into the tip of the small-diameter tube 1 or the like, and the production efficiency is improved.

The ultrasonic reflector 4 for forming the scan beam is driven by an externally provided stator, so that the diameter and size of the ultrasonic reflector 4 can be reduced as compared with the case where all the motors 17 are formed in the tube 1. It is planned.

Further, in the invention according to the first aspect, the probe is an insertion hole 10 for inserting the guide wire 9 to the outer wall
To enable insertion of the probe using the guide wire 9.

Further, according to the second aspect of the present invention, the rotation axis of the ultrasonic reflector 4 is disposed at a position eccentric with respect to the center axis of the acoustic head 2. Due to the eccentricity of the rotation center, the distance between the beam transmission position and the acoustic window changes, and the change in the image based on this change enables the accurate position and posture of the probe to be recognized.

According to the third aspect of the present invention, 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 forward of the probe is provided. Images can be obtained.

According to the fourth aspect of the present invention, the piezoelectric vibrator 3 and the like are incorporated in the acoustic head 2 and the probe is formed by fixing the acoustic head 2 to the tip of the tube 1. In addition, the manufacturing efficiency can be improved.

According to the fifth aspect of the present invention, a surplus length absorbing space 13 for absorbing the surplus length of the cable 8 is provided at a portion where the cable 8 is connected to the piezoelectric vibrator 3, and the piezoelectric vibrator 3 swings. Damage to the cable 8 during the moving operation is prevented.

According to the sixth aspect of the present invention, the distance between the acoustic transmitting / receiving surface 3a of the piezoelectric vibrator 3 and the acoustic window is formed so as to be different 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 becomes possible to accurately recognize the position and orientation of the probe from a change in the image based on this change.

Furthermore, in the invention according to claim 7 , the probe has an insertion hole 10 through which the guide wire 9 is inserted into the outer wall portion.
, And can be guided to a predetermined site by the guide wire 9.

According to the eighth aspect of the present invention, 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. It is possible to accurately recognize the position and posture of the tentacle.

According to the tenth aspect of the present invention, the joint portion between the acoustic head section 2 and the tube 1 has flexibility, and the acoustic head section 2 has a neck with respect to the central axis of the tube 1. Swing displacement is enabled. As a result, the probe can be deformed according to the curvature of a blood vessel or the like, and can be inserted deeper.

Further, in the invention according to claim 11 ,
The tube 1 is formed of a synthetic resin material mixed with a material having an excellent X-ray absorbing ability, so that the position of the probe can be easily grasped.

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

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. As shown in FIG. 1, a catheter-type ultrasonic probe according to the present invention
And an acoustic head 2 fixed to the tip of the tube 1
It is composed of

The acoustic head section 2 is inserted through the case 7 in which the opening at the distal end of the storage tube 12 is closed by the cap member 11, the permanent magnet 5, the ultrasonic reflector 4, and the tube 1 stored in the case 7. And the piezoelectric vibrator 3 connected to the cable 8.

The storage tube 12 and the cap member 11 constituting the case 7 are formed of, for example, a urethane-based synthetic resin material which is hard to coagulate blood. The connection between the cap member 11 and the storage tube 12 is made of an epoxy-based adhesive. It is adhered by the like. Further, it is desirable that the storage tube 12 be formed as thin as possible in order to serve as an acoustic window when transmitting and receiving ultrasonic waves.

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 rotating shaft 11a projecting from the rear wall surface of the cap member 11. The rotation is driven by the magnetic field formed by the stator.

The ultrasonic reflector 4 is formed in a shape obtained by cutting a cylindrical body so that the reflection surface 4a has an elliptical shape.
For example, the rear surface wall of the reflection surface 4a is integrated with the permanent magnet 5 by bonding it to 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 sound transmitting / receiving surface 3a facing the reflecting surface 4a of the ultrasonic reflector 4. . The piezoelectric vibrator 3 according to this embodiment has a sound transmitting / receiving surface 3
a is a focus type vibrator having a curvature so as to focus on a predetermined part in the body, and preferably, a backing material for preventing the ultrasonic wave from wrapping around the back surface during transmission is provided on the terminal forming surface. Placed in

The back surface of the piezoelectric vibrator 3 is placed in the storage cylinder 1.
By joining to the sealing flange 19 protruding from the inner wall of the storage tube 2, the inside of the storage tube 12 is sealed, and the acoustic impedance of the storage tube 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 saline is enclosed.

Acoustic head 2 constructed as described above
Are pre-assembled and fixed to the distal end of the tube 1 to form an ultrasonic probe. The sound head 2 can be fixed to the tube 1 by a known means such as adhesion or welding.

In addition, X such as BaBr2 is
If a material that absorbs X-rays is mixed in, it is possible to accurately know the position of the catheter when observing with X-rays, which is convenient for diagnosis.

Further, as shown in FIG. 2, when the insertion hole 10 for inserting the guide wire 9 into the distal end of the tube 1 and part or all of the acoustic head is formed, the catheter can be more accurately positioned at a predetermined position. Can guide.

Further, as shown in FIG. 3, the cross-sectional shape of the distal end of the tube 1 is made thinner toward the distal end, and a tapered portion 20 is formed at a corresponding portion of the acoustic head portion 2. When the acoustic head unit 2 is connected in a state where it is fitted, the acoustic head unit 2 can be displaced in a swinging manner with respect to the central axis of the tube 1, so that the catheter can be further moved along the curved portion of the blood vessel. It can be easily inserted.

The catheter-type ultrasonic probe according to this embodiment is inserted into a desired part in the body and then driven by a stator (stator) outside the body, so that it is moved to a region including the catheter. Due to the generated magnetic field, the permanent magnet 5 and the ultrasonic reflector 4 in the catheter rotate around the central axis, and a radial scan beam is transmitted to a predetermined site.

In this case, if a marker 14 for reflecting an ultrasonic wave is formed on the inner wall of the storage tube 12 serving as an acoustic window, the reflected echo of the window appearing in the received signal of the piezoelectric vibrator 3 can be used.
It is possible to know the insertion posture of the catheter in the blood vessel, such as the rotation angle of the ultrasonic reflector 4, and it is possible to specify the position of the obtained tomographic image in more detail.

The marker 14 can be formed by arranging a special material in the storage tube 12, but as shown in FIG. 4A, the cross-sectional shape of the inner wall of the storage tube 12 is reduced. It can also be realized by changing the parts. The same effect is obtained as shown in FIG.
The rotation center 4b of the ultrasonic reflector 4 is aligned with the central axis 1 of the storage cylinder 12.
It can also be realized by decentering 2a by δ.

FIG. 5 shows a second embodiment of the present invention. In the description of the present embodiment, the same components as those in the above embodiment are denoted by the same reference numerals in the drawings, and description thereof will be omitted. This embodiment shows a modification suitable for performing a sector scan of ultrasonic waves from the catheter insertion site forward,
A vibrator accommodation 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 slightly larger diameter than the outer diameter of the piezoelectric vibrator 3, and a hinge support groove which is opened outward on the opposing inner wall surface. 22.

On the other hand, as shown in FIG. 5A, the piezoelectric vibrator 3 has a cylindrical hinge portion 23 on the side wall and a terminal 24 on the back side of the sound transmitting / receiving surface 3a. 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 connected to the piezoelectric vibrator 3 in a state where an extra length is generated in the vicinity of the joining portion of the piezoelectric vibrator 3. The tube 1 is connected to the vibrator 3, and further has a surplus length absorption space 13 formed by extending the vibrator housing recess 21 rearward to absorb the surplus length portion.

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 holder 25 on the back surface, and in a state of being joined to the distal end 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 absorption space 13 of the tube 1
A gap between the wall of the cable and the cable 8 is filled with a sealing material 26, and a gap between the piezoelectric vibrator 3 and the cap member 11 is sealed with an acoustic medium 6 such as saline.

Therefore, in this embodiment, when the stator (stator) outside the body is driven after the catheter is inserted into a desired part in the body, the piezoelectric vibrator 3 having the permanent magnet 5 swings and moves forward. A sector scan beam is transmitted.

Also in this embodiment, if the marker 14 is formed on the cap member 11 serving as the acoustic window,
From the reflected 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 swing angle of the ultrasonic reflector 4, and to improve the position of the obtained tomographic image. It can be specified in detail.

Further, in the above description, the respective components such as the piezoelectric vibrator 3 are directly incorporated at the tip of the tube 1. However, as shown in the first embodiment, these respective components are used. 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 scanned forward in the sector, 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 The position can be captured in the ultrasonic image.

[0045]

As is apparent from the above description, according to the present invention, the ultrasonic reflector or the piezoelectric vibrator is driven to rotate by the magnetic field of the external stator, so that the catheter can be downsized. it can.

In the case where the components are incorporated in the acoustic head in advance, the production efficiency can be improved.

[Brief description of the drawings]

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

FIGS. 2A and 2B are views showing a modification of FIG. 1, wherein FIG.
(B) is a sectional view taken along line BB of (a).

FIG. 3 is a view showing still another modification of FIG. 1;

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

FIGS. 5A and 5B are views showing a second embodiment of the present invention, wherein 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]

 DESCRIPTION OF SYMBOLS 1 Tube 2 Acoustic head part 3 Piezoelectric vibrator 3a Sound transmitting / receiving 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

Continuation of front page (72) Inventor Kenji Kawabe 1015 Uedanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (56) References JP-A-5-344974 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61B 8/00-8/15

Claims (12)

(57) [Claims] 1. A tube (1) and an acoustic head (2)
A piezoelectric vibrator (3) for transmitting and receiving an ultrasonic beam; and an ultrasonic reflector (4) rotatably disposed in front of the piezoelectric vibrator (3). A permanent magnet (5) rotated by a magnetic field formed by a stator provided outside to rotate the ultrasonic reflector (4); and at least the ultrasonic reflector (4) and the piezoelectric vibrator (3). ) Is formed by housing a liquid acoustic medium (6) sealed in a gap between the piezoelectric vibrator (3) and the acoustic head (2). A catheter type ultrasonic probe which is connected to a distal end of the tube (1) by passing a cable (8) to be connected through the tube (1), and a guide wire (9) is passed through an outer wall portion. Insertion hole (1
0) is formed, and at a predetermined site by a guide wire (9).
A catheter-type ultrasonic probe that can be guided. 2. A rotary shaft of the ultrasonic reflector (4) has a sound axis.
Located at a position eccentric with respect to the central axis of the sound head (2)
The catheter-type ultrasonic probe according to claim 1, wherein the ultrasonic probe is used. 3. A tube through which a cable (8) is inserted.
(1) is connected to the cable (8), and the sound transmitting / receiving surface (3a) is connected.
Toward the open end of the tube (1)
Driven by a magnetic field formed by a piezoelectric vibrator (3) housed swingably at the end and a stator provided outside
Then, the piezoelectric vibrator (3) is connected to the central axis of the tube (1).
And a cap member for closing an open end of the tube (1).
(11) and a gap between the piezoelectric vibrator (3) and the cap member (11).
A catheter-type ultrasonic probe having a liquid acoustic medium (6) sealed in a gap . 4. The storage tube (12) and the sound transmitting / receiving surface (3a) are directed toward the open end of the storage tube (12).
And is swingably stored at the tip of the storage tube (12).
Driven by a magnetic field formed by the piezoelectric vibrator (3) and an externally provided stator
Then, the piezoelectric vibrator (3) is moved to the center axis of the storage tube (12).
And a cap member for closing an open end of the storage tube (12).
(11) and a gap between the piezoelectric vibrator (3) and the cap member (11).
Sound due to the liquid acoustic medium (6) sealed in the gap
A head section (2) is formed, and the acoustic head section (2) is connected to a piezoelectric vibrator (3).
Cable (8) into the tube (1)
A catheter type ultrasonic probe to be joined to the tip of the tube (1) . 5. A piezoelectric vibrator (3) for said cable (8).
The connection to the
A long absorption space (13) is provided.
The catheter-type ultrasonic probe as described in the above . 6. A sound transmitting / receiving surface of said piezoelectric vibrator (3).
The distance between (3a) and the acoustic window depends on the oscillation of the piezoelectric vibrator (3).
The catheter-type ultrasonic probe according to claim 3, 4 or 5, which varies depending on the angle . 7. A guide wire (9) is inserted through the outer wall.
Insertion hole (10) is formed, and the guide wire (9)
3. The method according to claim 3, wherein the guide can be guided to a predetermined portion.
7. The catheter-type ultrasonic probe according to 6. 8. The oscillating surface of the piezoelectric vibrator (3) is a guide.
Intersects with the wire (9) and can obtain the received image including the guide wire (9) image
A catheter-type ultrasonic probe according to claim 7 . 9. The sound head (2) is a tube.
5. The method according to claim 1, wherein the adhesive is fixed to the tip of (1).
On-board catheter-type ultrasonic probe. 10. The sound head (2) and a tube.
The joint with (1) is flexible and has an acoustic head.
Dod (2) swings about the center axis of the tube (1)
The catheter-type ultrasonic probe according to claim 9, which is capable of displacement . 11. The tube (1) has an X-ray absorption capability.
Claims made of synthetic resin mixed with excellent materials
Item 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10
Catheter-type ultrasonic probe. 12. A part of an acoustic window for transmitting and receiving ultrasonic waves.
Site with ultrasonic Den 搬特of different markers (14)
Formed and inserted from the image by the marker (14)
1, 2, 3, 4, 5, 6, 7,
12. The catheter-type ultrasonic probe according to 8, 9, 10 or 11 .