JPH06142209A - Medical tube - Google Patents

Abstract

PURPOSE:To provide a medical tube having an excellent operability in curving it, and having high safety in spite of a relatively simple constitution. CONSTITUTION:In a medical catheter 1, light-drive type chemo-mechanical substances 6a, 6b for driving a curving part by contraction and expansion are provided in its insertion part, and a control part 10 is provided for contraction and expansion of the chemo-mechanical substances 6a, 6b by irradiating the light-drive type chemo-mechanical substrances 6a, 6b selectively with light. By thus causing contraction and expansion of the chemo-mechanical substances 6a, 6b, a curving state of the insertion part of the catheter 1 can be controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical tube used for an insertion part of an endoscope, a catheter, etc., and more particularly to a medical tube having a bending mechanism for bending the insertion part.

[0002]

2. Description of the Related Art For example, in the insertion part of the digestive tract endoscope,
A bending portion that is remotely bent by an operation from the hand side is formed. Then, when the insertion portion of the endoscope is inserted into the body cavity, by remotely bending the bending portion, for example, insertion operability into the lumen of a complicated shape such as the digestive tract in the body Can be secured.

Further, even in a medical tube having an extremely small diameter such as a catheter for a heart or blood vessel or an endoscope for blood vessels, the tube is inserted by providing a curved portion in the insertion portion like the endoscope for a digestive tract. Operability is ensured. As a device for bending a medical tube having an extremely small diameter, for example, in Japanese Patent Application Laid-Open No. 62-292133, an actuator made of a shape memory alloy (SMA) is provided in an insertion portion of an endoscope, By driving the actuator by heating it by energization and deforming the actuator into a memory shape stored in advance, the insertion portion of the endoscope is curved in an arbitrary direction.

Further, in JP-A-1-320068, the pH is
It has been proposed to use an actuator that uses a chemo-mechanical substance whose volume changes by applying a change in electrical energy or electrical stimulation to bend the insertion portion of an extremely thin medical tube in an arbitrary direction. In other words, the actuator is installed in the insertion part of the extra-fine medical tube, and the chemo-mechanical substance is expanded / contracted by refluxing the solution having different pH or controlling the energization, and the insertion part of the medical tube can be moved in any direction. It is designed to be bent.

[0005]

However, in the configurations of these conventional devices, the following various problems occur. In the case of a tube bending mechanism of a type in which an actuator made of a shape memory alloy (SMA) is electrically heated and driven, there is a risk that the heat generated by the actuator during the bending operation of the insertion portion may cause thermal damage to the living body.
Further, since the actuator is energized, there is a risk of electrical damage to the living body due to electrical leakage, which requires safety and electrical insulation measures, which is not preferable in practice.

Further, in the case of a tube bending mechanism using an actuator of a system using an electrically driven chemo-mechanical substance, there is a problem that hydrogen gas is generated from an electrode portion which is in contact with the chemo-mechanical substance by energization. There is still a problem in terms of safety measures.

On the other hand, in the case of a tube bending mechanism of a type in which a chemo-mechanical substance is controlled by changing the pH, a structure for refluxing a solution having a different pH is required together with a leak countermeasure, so that the entire structure of the bending mechanism is considerably complicated. However, there is a problem in that the operation becomes complicated.

The present invention has been made in view of the above-mentioned problems, and an object thereof is a medical tube having a relatively simple structure but excellent bending operability and high safety. To provide.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a medical tube in which an insertion portion to be inserted into an object to be inspected is provided with a bending portion, and the insertion portion is bent by contraction and expansion. A light-driven chemo-mechanical substance that bends and drives the part is provided, and a bend control means that selectively irradiates the light-driven chemo-mechanical substance with light to cause the chemo-mechanical substance to contract and expand is provided. In this manner, the light-driven chemo-mechanical substance is provided in the insertion portion of the medical tube, and the chemo-mechanical substance is caused to contract and expand, thereby controlling the bending state of the bending portion of the insertion portion. Therefore, it is highly safe for the living body and has good operability when bending.

[0010]

1 and 2 show a medical catheter according to a first embodiment of the present invention. As shown in FIG. 1, this medical catheter device comprises a catheter 1 as a medical tube and an operating device for remotely operating the bending operation of the bending portion of the insertion portion thereof.

The catheter 1 comprises a multi-lumen tube formed of an elastic material such as silicone, which has a first lumen 2, a second lumen 3, a third lumen 4 and a fourth lumen 5. First lumen 2
Further, light-driven chemo-mechanical substances 6a and 6b as bending actuators for bending and driving the distal end of the insertion portion are inserted into the inner cavities of the respective distal ends of the second lumen 3. This light-driven chemo-mechanical material 6a,
6b is fixedly provided on the inner walls of the lumens 2 and 3.

The insertion portion of the catheter 1 provided with the light-driven chemo-mechanical substances 6a and 6b is a curved portion 7. Light-driven chemo-mechanical material 6a, 6
b has a function of contracting when it is irradiated with light and recovering its original length when the irradiation of light is stopped. Therefore, as will be described later, the bending portion 7 of the insertion portion of the catheter 1 is bent by contracting and expanding the light-driven chemo-mechanical substances 6a and 6b.

The light-driven chemo-mechanical substance 6a, 6
As b, for example, polyethyl acrylate film cross-linked with spirobenzopyran, nylon film-cyanostilbene mixed system, poly (2-hydroxyethyl methacrylate (PHEMA))-chrysophenine G (dye) system is used.

Further, inside the first lumen 2 and the second lumen 3, the chemo-mechanical substance 6a,
In the portion located on the rear side of 6b, an optical fiber 8a for irradiating the chemo-mechanical substance 6a, 6b with light,
8b is inserted. Then, each optical fiber 8a, 8
The emission tip of b is directed toward the rear end face of the chemo-mechanical substance 6a, 6b, and the transmitted light is transmitted to the chemo-mechanical substance 6a.
It is designed to irradiate a and 6b. Optical fiber 8
The proximal sides of a and 8b are connected to the light driving light source 9 via the control unit 10.

The control unit 10 selects the optical fibers 8a, 8b for sending the light of the light source 9 for light driving, and sends the light through the selected optical fibers 8a, 8b to the corresponding chemo-mechanical substances 6a, 6b. It is like this.
The control unit 10 is, for example, a joystick type operation lever 1
Optical fibers 8a, 8 operated by 1 to send light
Select b as an alternative.

On the other hand, the third and fourth lumens 4 and 5 are formed from the distal end to the proximal side and open at both ends, through which a channel is inserted through a not-shown treatment instrument or an insertion portion of a microscopic endoscope or the like. Is formed.

Next, a method of using the catheter 1 thus constructed will be described. The catheter 1 is inserted into the digestive tract such as the bile duct or the gallbladder duct, or the circulatory organ such as a blood vessel. Then, the extra-fine endoscope and the insertion portion of the treatment tool are inserted into the third and fourth lumens 4 and 5, respectively, and various treatments are performed simultaneously with the diagnosis. At this time, when it becomes necessary to bend the insertion part of the catheter 1 or bring the tip thereof close to the affected part, the control part 10 is operated to select the optical fibers 8a and 8b for transmitting the light of the light driving light source 9. . Then, one of the selected optical fibers 8a and 8b, for example, the optical fiber 8a is selected, and the light-driven chemo-mechanical substance 6a in the first lumen 2 is irradiated with light.

By irradiating light in this way, the light-driven chemo-mechanical substance 6a contracts, but since the chemo-mechanical substance 6a is fixed to the inner wall of the first lumen 2, it is as shown in FIG. In addition, the bending portion 7 of the catheter 1 bends toward the side on which the chemo-mechanical substance 6a is installed. Since the distal end of the insertion portion of the catheter 1 can be brought close to the affected area, various treatments and diagnoses can be easily performed. When the control unit 10 is operated to stop the light irradiation from the optical fiber 8a, the photo-driven chemo-mechanical substance 6a expands, so that the insertion part of the catheter 1 is restored to the original shape of the linear state. When the insertion portion is bent in the opposite direction, the other chemo-mechanical substance 6b may be irradiated with light through the optical fiber 8b.

Since the catheter 1 thus constructed has the bending mechanism constituted by providing the light-driven chemo-mechanical substances 6a and 6b at the distal end portion (bending portion) of the insertion portion, a conventional shape memory alloy ( Compared to the bending drive system using SMA), there is no problem of biological damage due to heat generation, and
It is also electrically safe. Further, unlike the electrically driven chemo-mechanical type, there is no problem of gas generation from the electrode portion. In addition, like the pH-driven chemo-mechanical type,
Since it is not necessary to reflux the H solution, the structure for that can be simplified and the operability can be improved.

FIGS. 3 and 4 show a second embodiment of the present invention. Catheter 1 according to the second embodiment
2 is a multi-lumen tube formed of a light-transmitting elastic material such as silicone as in the first embodiment, and this multi-lumen tube has four lumens located vertically and horizontally. The first lumen 13 and the second lumen 14 located at the upper and lower sides are closed at their tip ends. Also, the third lumen 15 and the fourth
The lumen 16 is communicated from the distal end to the proximal end and is open at both ends as in the first embodiment, and forms a channel through which a not-shown treatment tool or an insertion portion of an ultrafine endoscope is inserted.

A first balloon 17 is provided on the upper side of the distal end (curved portion) of the insertion part of the catheter 12, and a second balloon 18 is provided on the lower side of the distal end. Each of the balloons 17 and 18 is provided with a large number of small holes 19 communicating with the inside and outside thereof on the membrane wall,
The solution can go in and out of the balloons 17 and 18.

Light-driven chemo-mechanical substances 20a and 20b are provided inside the balloons 17 and 18, respectively. This light-driven chemo-mechanical material 20
An acrylamide gel containing a triphenylmethane leuco cyanide group is used as a and 20b. The light-driven chemo-mechanical substances 20a and 20b are neutral and have no charge in the non-irradiated state of acrylamide, but the leuco body of triphenylmethane is ion-dissociated by the irradiation of light to be converted into an ion gel. The ionic gel having a fixed charge contains a large number of mobile ions in the gel as compared with the external liquid, and as a result, the osmotic pressure of the gel becomes high.
This osmotic pressure causes the gel to swell, and the gel swells to the point where the osmotic pressure and the elasticity of the gel are balanced. When the irradiation of light is stopped, neutralization of ions occurs, returning to neutral gel again,
The osmotic pressure decreases and the elastic force of the gel restores the original contracted shape.

Further, the first and second lumens 13 and 14
Optical fibers 8a and 8b are respectively inserted in the inner cavities of the light-driving type chemistries, and the light from the light-driving light source on the hand side (not shown) is selectively received through a control unit (not shown). Irradiation of the mechanical substances 20a and 20b is possible.

A method of using the catheter 12 thus constructed will be described. First, the insertion part of the catheter 12 is used by inserting it into the digestive tract, blood vessel, or the like. If it becomes necessary to bend the tip of the insertion part, the following operation is performed. It is assumed that the light from the light source for optical driving is controlled by a hand side operation unit (not shown) to be guided to the optical fiber 8b in the second lumen, for example. Then, the light transmitted through the optical fiber 8b irradiates the light-driven chemo-mechanical substance 20b in the balloon 18. As described above, this light-driven chemo-mechanical substance 20b absorbs body fluid that has entered through the hole 19 of the balloon 18 by light irradiation and swells, and as shown in FIG. 4, the tip portion (curved portion) of the catheter 12 is placed on the upper side. Bend to. When the catheter 12 is returned to the straight state again, the light irradiation may be stopped.

On the contrary, when the distal end portion (bending portion) of the catheter 12 is bent downward, the operating portion on the proximal side selects the optical fiber 8a inserted in the first lumen 13 and Light is transmitted to the light-driven chemo-mechanical substance 20a in the balloon 17 to irradiate the light. Then, the distal end portion of the insertion portion of the catheter 12 can be curved downward by the same action as described above.

The catheter 1 constructed in this manner has the light-driven chemo-mechanical substances 20a, 20b at the insertion portion at the tip.
Since the bending mechanism is configured by providing the above, there is no problem that the living body is damaged by heat generation as compared with the conventional shape memory alloy (SMA) method, and it is electrically safe. Also,
Unlike the electrically driven chemo-mechanical type, there is no problem of gas generation from the electrode part. Further, unlike the pH-driven chemo-mechanical type, it is not necessary to recirculate the pH solution, which simplifies the configuration and improves the operability of bending.

5 and 6 show a third embodiment of the present invention. This is an example in which the catheter according to the third embodiment is applied to the insertion portion of the ultrafine endoscope 21. As shown in FIG. 5A, an objective lens 22 is provided at the center of the distal end of the insertion portion of the ultrafine endoscope 21, and the objective lens 22 has an image guide fiber 23 inserted through the insertion portion at the center thereof. The tips are opposed and optically coupled to it. Objective lens 22 and image guide fiber 2
A light guide fiber 24 is arranged around the circumference 3.

Further, inside the resin outer skin 25 constituting the insertion portion of the ultrafine endoscope 21, a pair of accommodating chambers which are vertically arranged and have a relatively long hole along the longitudinal direction of the insertion portion. 26 and 27 are formed. In each of the storage chambers 26 and 27, as described in the first embodiment, the light-driven chemo-mechanical substance 28 that contracts by light irradiation is used.
a and 28b are stored, and these are fixedly provided on the wall surfaces of the storage chambers 26 and 27 in which they are installed.
The light-driven chemo-mechanical substances 28a and 28b are
Each of them has a cylindrical shape as shown in FIG.

The cylindrical light-driven chemo-mechanical material 2
The distal ends of the optical fibers 30a and 30b guided from the proximal side of the endoscope 21 are inserted into the hollow interiors of 8a and 28b over substantially the entire length of the chemo-mechanical substances 28a and 28b. The chemo-mechanical substance 28a, 2
Optical fibers 30a, 30b arranged inside the hollow of 8b
The outer peripheral surface of the tip portion of the core is not coated, and is composed of only the core material. That is, when light is sent from the near side of the optical fibers 30a and 30b, the light is emitted from the outer peripheral surfaces of the optical fibers 30a and 30b in the hollow inside of the chemo-mechanical substances 28a and 28b as shown in FIG. 5B. It emits light from the whole,
The entire inner peripheral surface of the corresponding light-driven chemo-mechanical substance 28a, 28b is irradiated.

The optical fiber 30 for transmitting the driving light is used.
The selection of a and 30b is performed by a hand side operation unit (not shown), for example, by the control unit described above. Then, the light-driven chemo-mechanical substances 28a, 2 corresponding to the light are transmitted through the selected optical fibers 30a, 30b.
It is possible to irradiate the entire inner peripheral surface of 8b.

Next, the ultrafine endoscope 21 thus constructed
The bending operation will be described. When the insertion portion of the endoscope 21 is to be inserted into a very thin hollow organ such as a blood vessel, a bile duct, or a gallbladder duct, when the direction of the tip of the insertion portion needs to be changed, the following operation is performed. To do. In other words, when the light from the light driving light source (not shown) is guided to one of the optical fibers 30a (or 30b) by the hand side operation unit (not shown), the light is emitted from the entire outer circumference of the tip end portion of the optical fiber 30a (or 30b). To be done.

Then, one of the corresponding cylindrical light-driven chemo-mechanical substances 28a (28b) is irradiated with the light from the entire inner surface thereof. By this light irradiation, the light-driven chemo-mechanical substance 28a (28b) contracts similarly to the first embodiment described above, but since it is fixed to the inner wall of the storage chamber 26 (27), the endoscope 2
The tip portion of the insertion portion of No. 1 is curved by the generated force that accompanies this contraction. This makes it possible to diagnose the affected area.

In order to return the insertion portion 21 to the linear state, the operation portion on the hand side is operated to stop the light irradiation from the optical fiber 30a (30b), and the light-driven chemo-mechanical substance 2 in the contracted state.
It suffices to extend 8a (28b). Also, in the case of bending in the opposite direction, the optical fiber 30b (30a) on the opposite side is used.
Light is emitted from the opposite side, and light-driven chemo-mechanical substance 2 on the opposite side
It suffices to irradiate the inner peripheral surface of 8b (28a).

According to this structure, in addition to the effect of the first embodiment described above, the light from the optical fibers 30a and 30b can be irradiated over the entire axial direction of the chemo-mechanical substances 28a and 28b, so that the light energy can be efficiently used. Well communicated,
Responsiveness is improved.

FIG. 6 shows a fourth embodiment of the present invention. This embodiment is also an example applied to an ultrafine endoscope similarly to the above embodiments. This endoscope 32 is provided with a pair of storage chambers 26 and 27 at the distal end portion of its insertion portion, as in the third embodiment described above. The storage chambers 26, 27 are provided with light-driven chemo-mechanical substances 33a, 33b that contract by the same light irradiation as in the first and third embodiments.
These are fixed to the inner wall surfaces of the storage chambers 26 and 27 that store them. The light-driven chemo-mechanical material 33
Reference characters a and 33b are made of a transparent member having a light-transmitting property as a whole so as to be able to transmit light of optical fibers 35a and 35b, which will be described later, and are configured in a fiber bundle shape in which a plurality of fiber elements are bundled. .

The light-driven chemo-mechanical substance 33a,
An optical fiber 35a for transmitting light from an optical driving light source (not shown) on the hand side on the rear side of 33b,
35b is provided. Chemo-mechanical substance 33a,
The rear end of 33b and the front ends of the optical fibers 35a and 35b are optically connected by connecting portions 37 and 38. The other structure is the same as that of the third embodiment.

Next, how to use the thus configured endoscope 32 will be described. As in the case of the third embodiment described above, when it is necessary to insert the insertion portion of the endoscope 32 into the inside of a blood vessel, gallbladder duct, bile duct, etc., and bend the distal end portion of the insertion portion, an illustration is made. The light from the light source for optical drive is transmitted by the hand operation unit (control unit) to the one optical fiber 35a (3
5b). The light is transmitted to the light-driven chemo-mechanical material 33a (33b) through the connection portion 37 (38). Here, the light-driven chemo-mechanical substance 33a, (3
3b) is made of a translucent transparent material, and
Since it is in the form of a fiber bundle, light will be transmitted over the entire area.

When the light is transmitted, the light-driven chemo-mechanical material 33a (33b) contracts as described above, and the generated force associated with the contraction causes the distal end portion (curved portion) of the insertion portion of the endoscope 32. Bends towards its contracting side. The method of returning the insertion portion of the endoscope 32 to the straight state and the method of bending it to the opposite side are the same as those in the third embodiment.

According to the configuration of this embodiment, the above-mentioned first
In addition to the effects of the embodiment described above, light-driven chemo-mechanical substance 3
Since 3a and 33b are made of a transparent member having a light-transmitting property and are in the form of a fiber bundle, the efficiency of light transmission is improved and the response speed is increased.

FIG. 7 is an example of an ultrafine endoscope showing a fifth embodiment of the present invention. In this embodiment, only the material of the light-driven chemo-mechanical material in the above-mentioned third embodiment is changed. That is, the light-driven chemo-mechanical substances 39a and 39b are obtained by mixing a dye such as carbon black into a heat-driven chemo-mechanical substance that contracts when the temperature reaches a certain temperature or higher. That is, when the dye-containing chemo-mechanical substance 39a, 39b is irradiated with light, the dye absorbs the light and generates heat, and as a result, the heat-driven chemo-mechanical substance is contracted by the light. . For this type of heat-driven chemo-mechanical substance,
Polyvinyl methyl ether (PVME) gel or the like is used. The other structure is the same as that of the third embodiment.

The bending operation of the thus constructed ultrafine endoscope 21 will be described. The insertion portion of the endoscope 21 is a blood vessel, a bile duct,
When inserting into an extremely thin luminal organ such as the gallbladder, etc., the following operation is performed when it is necessary to change the direction of the distal end side of the insertion part. In other words, by the hand side operation unit not shown,
One of the optical fibers 30a (or 30
When the light is guided to b), the light is emitted from the outer peripheral surface of the optical fiber 30a (30b). Then, the one cylindrical light-driven chemo-mechanical substance 39a (or 39b) provided in the insertion portion is irradiated with the light from the inner peripheral surface thereof. The light-driven chemo-mechanical substance 39a (39b) contracts due to light irradiation as in the first embodiment.
Since this is fixed to the inner wall of the storage chamber 26 (27), the insertion portion of the endoscope 21 is curved by the generated force accompanying this contraction. This makes it possible to diagnose the affected area. In order to return the insertion portion to the linear state, the operator operates the hand side operation portion to stop the light irradiation from the optical fiber 30a (30b) and to contract the light-driven chemo-mechanical substance 39a.
It suffices to extend (39b). Further, in the case of bending in the opposite direction, light is emitted from the other optical fiber 30a (30b), and the light-driven chemo-mechanical substance 39b on the opposite side is emitted.
It suffices to irradiate the inner peripheral surface of (39a).

According to this, in addition to the effects of the first embodiment, the light from the optical fibers 30a and 30b can be irradiated over the entire axial direction of the chemo-mechanical substances 39a and 39b, so that light energy can be efficiently transmitted and a response can be obtained. The property is improved. The present invention is not limited to the above-mentioned embodiments, and various modifications can be considered within the scope of the invention.

[0043]

As described above, according to the present invention, since the swelling / contracting behavior of the light-driven chemo-mechanical substance is used for the bending mechanism of the medical tube, there is no damage to the living body due to heat generation as in the conventional method. There was no fear, and there was no problem in terms of electrical safety. Further, it is not necessary to recirculate the solution as in the case of using the pH-driven chemo-mechanical substance, so that the structure can be simplified and the operability at the time of bending can be improved. Further, there is no problem of gas generation from the electrode portion as in the case of using the electrically driven chemo-mechanical substance. As described above, the present invention can provide a medical tube having a relatively simple structure, excellent operability, and high safety.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a medical tube device according to a first embodiment of the present invention.

FIG. 2 is an explanatory view of a state where the bending portion of the insertion portion of the medical tube according to the first embodiment of the present invention is also curved.

FIG. 3 is an explanatory view showing an insertion portion of a medical tube according to a second embodiment of the present invention.

FIG. 4 is an explanatory view of a state where the bending portion of the insertion portion of the medical tube according to the second embodiment of the present invention is curved.

5A is an explanatory view showing an insertion portion of a medical tube according to a third embodiment of the present invention, and FIG. 5B is an enlarged view of a bending actuator portion similarly showing the third embodiment of the present invention. FIG.

FIG. 6 is an explanatory view showing an insertion portion of a medical tube according to a fourth embodiment of the present invention.

FIG. 7 is an explanatory view showing an insertion portion of a medical tube according to a fourth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Catheter, 6a, 6b ... Light-driven chemo-mechanical substance, 7 ... Bending part, 8a, 8b ... Optical fiber, 9 ... Light-driving light source, 10 ... Control part, 12 ... Catheter, 17 ... 1st balloon, 18 ... Second balloon, 20a, 20b
… Light-driven chemo-mechanical materials, 21… Ultra-fine endoscopes, 2
8a, 28b ... Light-driven chemo-mechanical substance, 30a,
30b ... Optical fiber, 33a, 33b ... Optically driven chemo-mechanical substance, 35a, 35b ... Optical fiber, 39a,
39b ... Light-driven chemo-mechanical substance.

Claims (1)

[Claims] 1. A medical tube having a curved portion in an insertion portion to be inserted into an object to be inspected, the optical drive being provided in the insertion portion and driving the bending portion of the insertion portion to bend by contraction and expansion. Type chemo-mechanical substance and a bending control means for selectively irradiating the light-driven chemo-mechanical substance with driving light to cause the chemo-mechanical substance to contract or expand. .