JPH03136668A - Internally inserting medical apparatus - Google Patents

Abstract

PURPOSE:To prevent the deflection of a flexible shaft and precisely move a linear moving body mounted on the top end of the flexible shaft within a range of a set quantity by elastically energizing a linear driving means for pushing and pulling the flexible shaft provided on other end side of the flexible shaft and the linear moving body provided on the top end side part of a hollow member toward the top end side of the hollow member. CONSTITUTION:A piston 22 as a linear moving body is connected to the top end of a flexible shaft 11. The piston 22 has a plurality of truncated conical members 22a constituted in the form in which their larger diameter parts are axially continued toward the top end side, with the vertical sectional side having nearly a saw-tooth form. In an injection catheter 4, a spring 25 as an energizing means energized in the extending direction is mounted between an injection catheter 4 and an integrated connector 24 to energize the flexible shaft 11 in such a manner that the flexible shaft is pulled toward an injection hole 4a. Hence, the deflection of the flexible shaft when pushed and pulled is prevented, and the following property of the linear moving body is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a medical device inserted into the body for diagnosis, treatment, etc., such as an implantable liquid injection device or an ultrasonic probe.

[Prior art] As a conventional implantable liquid injection device, for example,
There is one known from Publication No. 1-30719. This has a chemical liquid chamber for storing an injection liquid and a driving chamber formed inside the housing, and these two chambers are partitioned by a bellows. One end of a capillary tube is connected to the drug chamber, and the other end of the capillary tube is guided to a target site within the body. Further, the drive chamber is filled with, for example, Freon gas, and this Freon gas expands when heated by body temperature, contracts the bellows, and injects the medicinal solution into the target site in the body through the capillary tube.

[Problem to be solved by the invention]

However, with this conventional implantable injection device, the pump action of Freon gas, which expands due to body temperature and contracts the bellows, pushes the medicinal liquid into the capillary tube and injects it into the target area within the body. It is greatly affected by changes in the internal flow path resistance and the contraction action of the bellows depending on body temperature. Therefore, it has not been possible to accurately inject the medicinal solution into the target site within the body. Also,
Its structure is also quite complex, making it difficult to place it inside the body.

For this reason, an unpublished application (patent application No. 1-20881)
In No. 4), a linear moving body whose outer peripheral surface has a serrated cross-sectional shape is provided inside the drug solution injection catheter, and the linear moving body is moved back and forth in the length direction of the catheter via a flexible shaft to feed the liquid.

However, in this body-implantable liquid injection device, the flexible shaft is easily bent within the catheter, and when the flexible shaft is bent, the linear moving body does not move forward and backward according to the set settings, and the amount of liquid sent becomes inaccurate.

In addition, in the same unpublished application (Utility Application No. 1-61216), one end of the catheter has
An ultrasonic probe has been proposed in which an ultrasonic transducer unit provided as a linear moving body is moved back and forth via a flexible shaft in the same manner as described above to obtain an ultrasonic tomographic image of a desired location within a body cavity.

In the case of this type of ultrasonic probe, as described above, a tomographic image within a set range cannot be accurately obtained due to the deflection of the flexible shaft.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a linear moving body at the distal end portion of a long hollow member to be inserted into a living body, and move this body forward and backward within the body using a flexible shaft. To configure an insertion medical device so that the linear moving body can be moved accurately as set even though the linear moving body is moved forward and backward by a flexible shaft.

[Means and effects for solving the problems] In order to solve the above problems, the present invention provides a long hollow member to be inserted into a living body, a flexible shaft inserted into the hollow member so as to be freely advanced and retractable, and the hollow member. a linear moving body provided at the distal end of the hollow member and connecting the distal end of the flexible shaft; a linear drive means disposed at the other end of the flexible shaft for pushing and pulling the flexible shaft; and means for biasing the linear moving body toward the distal end side of the hollow member.

Since a means for urging the linear moving body toward the tip side of the hollow member is provided, the flexible shaft can be prevented from deflecting when the flexible shaft is pushed or pulled, and the linear moving body attached to the tip of the flexible shaft can be prevented from bending. can be moved accurately within a set amount.

Embodiment FIGS. 1 to 5 show a first embodiment of the present invention.

FIG. 2 and FIG. 3 show the overall structure of the implantable liquid drug injector l. This is used by being implanted under the skin A as shown in FIG.

The specific configuration of this implantable liquid drug injection device 1 will be described below. That is, this liquid medicine injection device 1 includes a drive unit 2, a liquid medicine boat 3 connected to the drive unit 2, and an injection catheter 4 as a long hollow member inserted into a living body. The drug port 3 is connected to the injection catheter 4 midway near the proximal end thereof.

The drive unit 2 serves as a linear drive means for a piston as a linear moving body to be described later, and a housing 2a of the drive unit 2 is made of a non-extensible material. As shown in FIGS. 3 and 5, a motor 5, a control section 7 connected to the motor 5 via a lead wire 6, and a battery 8 are incorporated inside the housing 2a, and the entire structure is integrated. It becomes.

Furthermore, inside the housing 2a, the motor 5
A rotating disc 10 is fixed to the rotating shaft 9, and a proximal end of a flexible shaft 11 inserted into the injection catheter 4 is rotatably connected to a part of the periphery of the disc 10. ing. That is, the flexible shaft 11
The base end portion of is connected at an eccentric position with respect to the disk 10, and functionally constitutes a crank mechanism. For this reason,
When the disc 10 rotates due to the rotation of the rotating shaft 9, the proximal end portion of the flexible shaft 11 makes a rocking motion within the housing 2a, but the flexible shaft 110 portion within the injection catheter 4 makes a linear reciprocating motion. In this way, the rotation of the rotating shaft 9 is converted into linear reciprocating motion of the flexible shaft 11.

The injection catheter 4, which is fluid-tightly connected to the drive unit 2, is made of a non-stretchable flexible tube made of polyurethane or the like, and the flexible shaft 11 moves back and forth in the axial direction within the injection catheter 4. It can be inserted freely. Furthermore, a single-shaped connecting tube 12 is interposed in the middle of the injection tube 4, and this single-shaped connecting tube 12 is connected to the chemical liquid boat 3 via a chemical liquid tube 13.

Therefore, the inside of the drug solution boat 3 is communicated with the inside of the injection catheter 4 via the drug solution tube 13.

By the way, the chemical liquid port 3 is configured as shown in FIGS. 3 and 4. That is, the main body 3a of the drug boat 3 has a puncture hole 1 that opens toward the surface on the skin A side.
It is equipped with 5. A puncture wall 16 is provided inside the puncture hole 15, through which an injection needle (to be described later) is pierced, and the puncture wall 16 is made of silicone rubber or the like having self-sealing properties. A needle retaining wall 17 is provided below the puncture hole 15, and a reservoir 18 for storing a medicinal solution is provided below the needle retaining wall 17 so as to communicate with the puncture hole 15 through a communication hole 19. The reservoir 18 is formed of an elastic membrane made of stretchable silicone rubber. and,
The reservoir 18 is provided with a liquid feeding port 21, and this liquid feeding port 2
1 to which the chemical liquid tube 13 is connected.

On the other hand, as shown in FIG.
A piston 22 is connected to the tip of the piston 1 as a linear moving body. The piston 22 has a plurality of truncated conical members 22a arranged in series in the axial direction with the large diameter side facing the tip side, and the vertical side surface shape is approximately serrated.

The outer circumferential surface of the piston 22 is close to the inner circumferential surface of the injection catheter 4, and the tip of the piston 22 reaches near the injection port 4a, which is the opening at the tip of the injection catheter 4.

Further, a stopper 23 is fixedly provided at an intermediate portion of the flexible shaft 11, which is located close to the piston 22 and closer to the proximal end thereof.

Furthermore, a spring 25 is installed between the injection catheter 4 and the connector 24 provided integrally with the injection catheter 4 as a biasing means to push the flexible shaft 11 toward the injection port 4a. It is biased to pull it towards the target. That is, the connector 24 is formed into an intermediate cylindrical shape, and the flexible shaft 11 is passed through the hollow portion so as to be freely movable forward and backward.

Next, the operation of the implantable liquid drug injection device 1 configured as described above will be explained. The drive unit 2, drug boat 3, and injection catheter 4 of this drug injector 1 are connected to the skin A.
At the same time, the injection port 4a at the tip of the injection catheter 4 is placed and fixed in the target site for injection of the drug solution, for example, in the hepatic artery in the case of injection of an anticancer drug for liver cancer.

When injecting a medicinal solution into the reservoir 18 of the medicinal solution port 3, it is performed as follows. First, an injection needle of a medicinal liquid syringe (not shown) is percutaneously penetrated into the puncture wall 16 of the medicinal liquid boat 3 . Then, the chemical solution is injected into the reservoir 18. As a result, the reservoir 18 expands and the medicinal solution is stored in the reservoir 18.

Furthermore, when injecting the drug into a target site within a living body, the motor 5 is driven by a signal from the control unit 7 . When the rotating shaft 9 of the motor 5 rotates, the disc 10 rotates, and this rotational force is transferred to the flexible shaft 11 via the crank mechanism.
is transmitted as a linear reciprocating motion. When the flexible shaft 11 linearly reciprocates inside the injection catheter 4, the piston 22 moves linearly reciprocally inside the distal end side of the injection catheter 4, and the drug solution inside the injection catheter 4 is sent out from the injection port 4a. That is, the piston 22 has a substantially serrated longitudinal section, and the resistance to the chemical solution is large when moving in the delivery direction and small when moving in the opposite direction, so that the drug solution is discharged in one direction in the delivery direction. become. Therefore, the reciprocating movement of the piston 22 forces the liquid medicine inside the injection catheter 4 to be released.
The drug solution can be accurately injected into the injection target site.

In addition, since the injection catheter 4 communicates with the reservoir 18 via the drug tube 13, the drug is gradually delivered from the reservoir 18 toward the injection port 4a.
Administer from the point to the target site. The amount of drug injected at this time is
This can be adjusted by controlling the rotation speed of the motor 5.

Since the flexible shaft 11 is always pulled toward the injection port 4a by the spring 25, the shaft 11 does not bend during linear reciprocating motion. Therefore, it is possible to prevent the linear reciprocating movement of the piston 22 from becoming inaccurate due to the deflection of the shaft 11, thereby preventing errors in the injection amount from occurring.

6 and 7 show a second embodiment of the present invention.

In this embodiment, as shown in FIG. 6, an ultrasonic probe 51 is introduced from an endoscope 52 using a channel of an endoscope 50, and an ultrasonic probe 51 is introduced from an outlet 53 of the channel.
Introduce the distal end of the tube into the desired site within the body cavity.

The base of the ultrasonic probe 51 is made of a catheter 51a made of polyethylene, Teflon, etc., and an ultrasonic transducer unit 54 as a linear moving body is built in the distal end of the catheter 51a, as will be described later. A linear drive unit (means) 55 such as a rack and pinion mechanism is provided at the base end of the ultrasonic probe 51. This ultrasonic transducer unit 54 not only moves the linear moving body but also is excited and performs linear scanning. An imaging device 57 is connected to the linear drive unit 55 for processing received echo signals from the subject and transmitting the processed signals to a monitor 56.

The light guide cable 5 of the endoscope 50 is connected to the imaging device 57.
Five light source devices are attached to which 8 are connected.

The ultrasonic transducer unit 54 as a linear moving body built into the tip of the ultrasonic probe 51 is configured and incorporated as shown in FIG.

That is, the transducer unit 54 is formed by supporting a piezoelectric element, a matching layer, an absorption layer, etc. on a support member 61, and emits ultrasonic waves when electrically excited. Further, the support member 61 is held by a cylindrical support frame 62 made of polycarbonate, for example. The transducer unit 54 is movable within the inner space 64 at the tip of the ultrasound probe 51. A plurality of rings 63 are fitted around the outer periphery of the support frame 62. In other words, the transducer unit 54 is connected to the inner space 6 at the tip of the ultrasonic probe 51.
It is designed to move airtightly within the room. The transducer unit 54 is fixed with its ultrasonic emission surface facing outside of the support frame 62.

The sealed space formed by the radiation surface of the transducer unit 54 and the inner diameter surface of the catheter 51a is filled with ultrasound gel 67, which is an ultrasound transmission medium.

A coaxial cable 65 is connected to this vibrator unit 54, and several to several
Excitation drive power of several tens of MH2 is supplied from IH2. Further, the coaxial cable 65 is connected to a coil shaft 60 connected to the support member 61 of the vibrator unit 54.
It is connected to the linear drive unit 55 through the inside of the unit. The tip end of the coil shaft 60 is located in a cylindrical support frame 62 and fixed to the support member 61 with an adhesive 66.

A light frame 72 having an aperture 71 is attached to the tip of the ultrasonic probe 53 . Further, in the inner space 64 near the tip of the ultrasonic probe 53, a transducer unit 5 is provided.
A substantially hollow cylindrical connector 73 is provided at an appropriate position on the proximal side of the connector 4. The connector 73 is integrally fixed to the catheter 51a forming the base of the ultrasound probe 51. The coil shaft 60 is passed through the hollow portion of the connector 73.

Moreover, the inner space 6 between this connector 73 and the support frame 62
A spring 74 biased in the direction extending in the axial direction is interposed in the transducer unit 4, and the spring 74 biases the transducer unit 54 toward the tip side of the ultrasonic probe 51. There is. The connector 73 connects the catheter 51a, which forms the base of the ultrasound probe 51, divided into front and rear parts. Further, the gap where the catheter 51a is cut is filled with an adhesive 75 and sealed.

Next, the operation when using this ultrasonic probe 51 will be explained. As shown in FIG. 6, after the transducer unit 54 is inserted into a desired position within the body cavity, power is supplied to the transducer unit 54 to excite it, and at the same time the linear drive unit 55 on the proximal side pushes and pulls the transducer unit 54 via the coil shaft 60. The vibrator unit 54 is moved back and forth within the inner space 64 (linear reciprocating motion). Ultrasonic waves are emitted from the transducer unit 54 through the ultrasound gel and the wall of the catheter 51a, and reflections from the living body are received. This echo signal is transmitted through the coaxial cable 65. This is then processed and displayed on the monitor 56 of the image device 57.
An ultrasonic tomographic image is projected.

By the way, when retracting the vibrator unit 54, a tensile force acts on the coil shaft 60.

Therefore, the coil shaft 60 does not bend.

Furthermore, when the vibrator unit 54 is moved forward, a compressive force acts on the coil shaft 60. However, since the vibrator unit 54 is urged forward by the spring 74, the forward movement of the vibrator unit 54 is ensured, and the coil shaft 60 is prevented from deflecting.

In this manner, the coil shaft 60 does not bend during the linear reciprocating movement of the vibrator unit 54.

Therefore, accurate scanning is performed within the set range, and a good tomographic image is obtained.

FIG. 8 shows a third embodiment of the present invention. In this embodiment, a tension spring 81 is inserted between the optical frame 72 of the ultrasonic probe 51 and the support frame 62 of the transducer unit 54. Each end of the tension spring 81 is fitted into the corresponding end of the light frame 72 and the support frame 62, and secured by soldering or other suitable means.

That is, in this embodiment, a tension spring 81 is provided on the distal side of the transducer unit 54, and the tension spring 81 urges the transducer unit 54 in the forward direction.

Therefore, the action of this tension spring 81 is similar to that of the spring 74 described above, and the coil shaft 60 does not bend during linear reciprocating motion of the vibrator unit 54.

Note that the present invention is not limited to the above embodiments.

[Effects of the Invention] As explained above, the present invention provides a means for biasing the linear moving body toward the distal end side of the hollow member, and thus prevents the flexible shaft from deflecting when the flexible shaft is pushed or pulled. , improves followability of linear moving bodies,
In addition, the linear moving body attached to the tip of the flexible shaft can be accurately moved within a set amount range.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of the present invention, and FIG. 1 is a side sectional view of the distal end portion of an implantable liquid drug injection device;
FIG. 2 is a side view of the implantable drug injector, FIG. 3 is a cross-sectional plan view of the implantable drug injector, and FIG. 4 is the installation of the drug port 1. FIG. 3 is a sectional view of the vicinity of the tip of the ultrasonic probe in Example 3; DESCRIPTION OF SYMBOLS 1... Implantable liquid drug injector, 2... Drive unit, 4... Injection tube, 5... Motor, 9...
Rotating shaft, 1... Disk, 11... Flexible shaft, 22... Piston, 25... Spring, 51
... Ultrasonic probe, 54 ... Transducer unit, 6
0...Flexible shaft, 81...Tension spring.

Claims (1)

[Claims] A long hollow member to be inserted into a living body, a flexible shaft inserted into the hollow member so as to be freely advanced and retractable, and a linear moving body provided at the distal end portion of the hollow member and connecting the distal end of the flexible shaft; A linear drive means provided at the other end of the flexible shaft to push and pull the flexible shaft; and a linear drive means provided at the distal end of the hollow member to elastically urge the linear moving body toward the distal end of the hollow member. What is claimed is: 1. A medical device inserted into the body, characterized by comprising means for: