JP2007125256A - Medical tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical tool which can securely penetrate a narrowed portion caused in a lumen in a living body. <P>SOLUTION: A wire 1A is used while being inserted into the living body. The wire A has a long wire body 2 and a deformed part 3A provided at the distal end of the wire body 2A and expanded and contracted in the longitudinal direction of the wire body 2A. The deformed part 3A has an electrical activated polymer 41 deformed by energizing and two electrodes 42a and 42b for energizing the electrical activated polymer 41, and is provided with an actuator 4A for expansion and contraction operating so as to expand and contract in the longitudinal direction of the wire body 2 by applying power between the electrodes 42a and 42b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a medical device used by being inserted into a living body.

  For example, when a stenosis or obstruction occurs in a body lumen such as a blood vessel, bile duct, trachea, esophagus, urethra, etc., treatment is required to eliminate the stenosis or obstruction and restore these functions. . As an example of such treatment, angioplasty applied to ischemic heart disease will be described.

  In response to the rapid increase in the number of patients with ischemic heart disease (angina pectoris, myocardial infarction, etc.) due to the westernization of dietary habits in Japan, percutaneous transvascularization has been proposed as a method for reducing these diseases. Coronary angioplasty (PTCA) has been performed and has become widespread. PTCA is a long hollow tube called a guide catheter with a small incision in the artery of the patient's leg or arm and placement of an introducer sheath (leader) through the lumen of the introducer sheath, with the guide wire leading. After inserting the tube into the blood vessel and placing it at the entrance of the coronary artery, withdraw the guide wire, insert another guide wire and balloon catheter into the lumen of the guide catheter, and X-ray the balloon catheter while leading the guide wire Under contrast, advance to the lesion (stenosis or occlusion) of the patient's coronary artery, position the balloon in the lesion, and at that position, the doctor moves the balloon at a predetermined pressure for about 30 to 60 seconds once or multiple times It is a technique to inflate. This dilates the vascular lumen of the lesion, thereby increasing blood flow through the vascular lumen.

  However, when the stenosis of the lesion is tight and almost obstructed, the balloon catheter may not pass through the lesion.

  Therefore, a catheter (catheter for coronary artery penetration) for penetrating a lesion before inserting a balloon catheter has been developed (see, for example, Patent Document 1). This catheter has a tubular body having a guide wire lumen and a port provided on the proximal end side of the tubular body, and is configured to insert the guide wire from the port into the guide wire lumen.

  However, since the catheter described in Patent Document 1 is composed of a hollow tubular member over its entire length, it has high flexibility (flexibility) over its entire length. Part) is thinner than that, and the pushing force applied from the proximal side (port) is not easily transmitted to the distal end side, and it may be difficult to penetrate the constricted part.

  Also, for example, when the stenosis is composed of a thrombus (emboli), thrombolytic therapy using a thrombolytic agent that dissolves the thrombus may be used. There is a problem that thrombus cannot be rapidly removed (dissolved), for example, there is a thrombus that does not dissolve with a thrombolytic agent.

JP 2002-301161 A

  An object of the present invention is to provide a medical device capable of reliably penetrating a narrowed portion generated in a lumen in a living body.

  Such an object is achieved by the present inventions (1) to (8) below. Moreover, it is preferable that it is following (9)-(15).

(1) A medical device used by being inserted into a living body,
A long linear body, and a deformed portion that is provided at the tip of the linear body and expands and contracts in the longitudinal direction of the linear body,
The deformable portion has an electroactive polymer that deforms when energized and at least two electrodes for energizing the electroactive polymer, and expands and contracts in the longitudinal direction of the linear body when energized between the electrodes. A medical device comprising a telescopic actuator that operates as described above.

  (2) The medical device according to (1), wherein the expansion / contraction actuator is configured by a multilayer structure in which layered electroactive polymers and layered electrodes are alternately stacked.

  (3) The medical device according to (1) or (2), wherein the degree of expansion / contraction of the expansion / contraction actuator can be set by a magnitude of a voltage applied between the electrodes of the expansion / contraction actuator.

  (4) Said (1) thru | or (3) comprised so that the expansion-contraction speed of the said expansion-contraction actuator can be adjusted by changing the magnitude | size of the voltage applied between the said electrodes of the said expansion-contraction actuator over time. ) The medical device according to any one of

  (5) Said (1) thru | or which has a fixing | fixed part provided in the location of the base end side from the said deformation | transformation part of the said linear body, and fixing the said linear body with respect to the body cavity in which the said linear body was inserted. The medical device according to any one of (4).

  (6) The medical device according to (5), wherein the fixing portion includes a fixing deformation portion that is deformed so that the outer diameter increases or decreases.

  (7) The fixing deformation portion has an electroactive polymer that is deformed by energization and at least two electrodes for energizing the electroactive polymer, and operates to expand when energized between the electrodes. The medical device according to (6), further including a fixing actuator.

  (8) The medical device according to any one of (5) to (7), wherein the fixing portion is provided with fixing auxiliary means for assisting the fixing.

  (9) The medical device according to (7), wherein the fixing actuator includes a multilayer structure in which layered electroactive polymers and layered electrodes are alternately stacked.

  (10) The medical device according to (7) or (9), wherein the telescopic actuator and the fixing actuator operate independently.

  (11) The configuration according to (7), (9), or (10), wherein the degree of expansion of the fixing actuator can be set by a magnitude of a voltage applied between the electrodes of the fixing actuator. Medical tools.

  (12) The above-described (7), (9) configured to be able to adjust the expansion speed of the fixing actuator by changing the magnitude of the voltage applied between the electrodes of the fixing actuator over time. ) To the medical device according to any one of (11).

  (13) The medical device according to (8), wherein the fixation assisting means is minute unevenness provided on a surface that contacts the inner surface of the body cavity.

  (14) The medical device according to (8), wherein the fixing assisting unit includes an engaging member that operates in accordance with a fixing operation of the fixing portion and engages with an inner surface of a body cavity.

  (15) The medical device according to any one of (1) to (14), wherein the linear body is a wire or a catheter.

  According to the present invention, since the deformable portion provided at the tip of the linear body includes the expansion / contraction actuator that operates to expand and contract in the longitudinal direction of the linear body, the expansion / contraction actuator extends. Thus, the deformed portion can enter the narrowed portion, and thus the narrowed portion generated in the lumen in the living body can be surely penetrated.

  Further, in the case of having the fixing portion, the proximal end side can be reliably fixed from the deformed portion of the linear body, and therefore, when the deformed portion enters the constricted portion due to the extension of the expansion / contraction actuator, The deformed portion is reliably prevented from being pushed back to the proximal end side. As a result, the medical instrument of the present invention can more reliably penetrate the narrowed portion generated in the lumen in the living body.

Hereinafter, the medical device of this invention is demonstrated in detail based on suitable embodiment shown to an accompanying drawing.
<First Embodiment>
FIG. 1 is a longitudinal sectional view showing an embodiment (first embodiment) when the medical device of the present invention is applied to a wire ((a) is a state where the electrodes are not energized, and (b) is a state between the electrodes. 2 is a cross-sectional perspective view taken along line AA in FIG. In the following, for convenience of explanation, the right side in FIG. 1 is referred to as “base end” and the left side is referred to as “tip”.

  In the present embodiment, the medical device of the present invention is applied to a wire used by being inserted into a living body. This wire (linear body) 1A is, for example, a stenotic part or an obstructed part (hereinafter referred to as “blood vessel”) in a living body lumen (hereinafter referred to as “blood vessel”) such as a blood vessel, bile duct, trachea, esophagus, urethra, etc. The stenosis portion and the occlusion portion are collectively referred to simply as “stenosis portion”).

  A wire 1A shown in FIG. 1 includes a wire main body 2A, a deformed portion 3A bonded to the tip end of the wire main body 2A, and a tip soft tip 32 bonded to the tip end of the deformed portion 3A. It has embedded electrodes 42a and 42b.

  In the wire body 2A, a core wire (core material) 25 is embedded, and lead wires 44a and 44b for supplying electrodes to the electrodes 42a and 42b are embedded in the major axis direction. The lead wire 44b of the present embodiment may use the core wire 25, but when the conductivity of the core wire 25 is insufficient, the core wire 25 may be covered with copper, platinum or the like. The material of the portion where the core wire 25 is embedded (hereinafter referred to as “electroactive polymer 21”) may be the same as or different from the material described below (electroactive polymer 21), but can be joined to the deformable portion 3A. It is necessary to be.

  The electroactive polymer 21 may include any polymer or rubber having a substantially insulating property that is deformed according to an electrostatic force or whose electric field is changed by the deformation. Specifically, examples of the electroactive polymer 21 include those containing NuSil CF19-2186 (manufactured by NuSil Technology), and any dielectric elastomer polymer, silicone rubber, fluoroelastomer, Dow Corning 730 (Dow Corning). Silicone polymer such as 4900 VHB acrylic series (manufactured by 3M), and the like.

  The deformable portion 3A is made to pass from the state shown in FIG. 1A by energizing the electroactive polymer 21 (hereinafter referred to as “electroactive polymer 41a”) located between the electrodes 42a and 42b. 1B, that is, the deformed portion 3A is extended. Further, the deformed portion 3A in the expanded state contracts to the initial state when the energization of the deformable portion 3A to the electroactive polymer 41a is not energized.

  Here, “to energize” refers to applying a voltage to the electroactive polymer 41a by the electrodes 42a and 42b. In the following description, the state shown in FIG. 1A (also in FIGS. 3A and 5A) is referred to as an “initial state”, and FIG. 1B (FIG. 3B and FIG. The state shown in FIG. 5B is also referred to as “extended state”.

  As shown in FIGS. 1 and 2, a tip soft tip 32 is joined to the tip of the deformable portion 3A, and the tip 31 of the tip soft tip 32 is rounded. Thereby, the wire 1A can smoothly and reliably pass through the narrowed portion from the tip 31 in the extended state. Moreover, damage to the blood vessel by the tip 31 can be reliably prevented.

  The electrode 42a and the electrode 42b are connected to a power source (not shown) via lead wires 44a and 44b embedded in the wire body 2A, respectively, and are used to energize the electroactive polymer 41a. The power source performs various controls such as timing control (sequence control) of energization / disconnection between the electrodes 42a and 42b, control of applied voltage, and stop control (including error processing) when an abnormality occurs. have.

  The electrode 42a is composed of a rod-shaped body having a circular cross section. The electrode 42 a is disposed on the central axis of the wire body 2 </ b> A and extends to the proximal end surface of the distal end soft tip 32.

  The electrode 42b is configured by a cylindrical body having a circular cross section. The electrode 42b is provided concentrically with the electrode 42a. The inner and outer diameters of the electrode 42b are substantially constant along the longitudinal direction of the wire body 2A.

  The tip 421 of the electrode 42b and the tip 422 of the electrode 42a are in the same position in the longitudinal direction of the wire body 2A in the initial state.

  The electrode 42a and the electrode 42b may be made of a conductive material, and in particular, fine particles of metal such as gold, silver, platinum, and copper, carbon black, carbon nanotubes, and the like can be used. A mixture of these materials and the constituent material of the electroactive polymer 21 can be used.

  In addition, for example, at least one layer made of a material different from the metal material constituting the electrode 42a may be laminated on the electrode 42a (the same applies to the electrode 42b).

  As a constituent material of the layer to be laminated, for example, a material whose conductivity is larger than that of the electroactive polymer 41a and smaller than that of the electrode 42a can be cited. Examples of such a constituent material include, but are not limited to, fluoroelastomers containing carbon black and colloidal silver, aqueous latex rubber emulsions containing a relatively small amount of sodium iodide, tetrathiafulvalene / tetracyanoquinoji. Examples include polyurethane containing a methane (TTF / TCNQ) charge transfer medium, and one having one or more of these as a main material can be used.

  When a layer made of such a material is provided on the electrode 42a, for example, when a voltage is applied between the electrodes 42a and 42b by the power source, the charge distribution near the inner peripheral surface 412 of the electroactive polymer 41a That is, the charge can be concentrated in the vicinity of the inner peripheral surface 412 of the electroactive polymer 41a.

  In addition, for this reason, the layer provided on the electrode 42a can be referred to as a charge distribution layer.

Next, the operation of the wire 1A configured as described above will be described.
By applying a voltage between the electrodes 42a and 42b of the expansion / contraction actuator 4A in the initial state, the positive charge is uniformly distributed around the outer peripheral surface 411 of the electroactive polymer 41a, that is, positively charged. Further, the negative charge is uniformly distributed around the inner peripheral surface 412 of the electroactive polymer 41a, that is, it is negatively charged.

Thereby, in the electroactive polymer 41a, the positively charged outer peripheral surface 411 attracts the negatively charged inner peripheral surface 412. As a result, the distance (thickness t ₁ ) between the outer peripheral surface 411 and the inner peripheral surface 412 decreases.

Here, the volume of the electroactive polymer 41a is constant, the partial thickness t ₁ is reduced, the length L of the deformation portion 3A is increased, the deformation portion 3A is extended state.

  Further, both end portions of the deformable portion 3A are connected to the tip soft tip 32 and the wire body 2A, respectively, which are not easily deformed in outer diameter. Therefore, in the extended state, both end portions of the deformable portion 3A The deformation of the diameter is slight, and the intermediate portion of the deformation portion 3A is deformed so that the deformation of the outer diameter becomes small, that is, constricted (see FIG. 1B).

  In the extended deformed portion 3A, when the application of the voltage between the electrodes 42a and 42b is stopped, the inquiry between the outer peripheral surface 411 and the inner peripheral surface 412 is eliminated. As a result, the shape of the electroactive polymer 41a is restored, and thus the deformed portion 3A is in the initial state.

  Thus, in the deformable portion 3A, the expansion / contraction actuator 4A that expands and contracts the deformable portion 3A in the longitudinal direction by the electrode 42a, the electrode 42b, and the electroactive polymer 41a positioned between the electrodes 42a and 42b is provided. It is configured.

  The expansion / contraction actuator 4A is configured to set the degree of expansion / contraction depending on the magnitude of the voltage applied between the electrodes 42a and 42b.

In other words, when the applied voltage is set to the maximum within the allowable voltage range that can be applied to the expansion / contraction actuator 4A, the deformation portion 3A expands to the maximum, and the length L Becomes the maximum (L _max ). In addition, when the voltage to be applied is set to the minimum, that is, zero, the deforming portion 3A does not expand, and the length L is minimum (L _min ), that is, the initial state. Further, when the voltage to be applied is set to an arbitrary magnitude between the maximum and minimum, the deforming portion 3A has a length L between the length L _max and the length L _min .

  Since the degree of expansion / contraction of the expansion / contraction actuator 4A can be set in this way, for example, according to the distance between the narrowed portion and the distal end 31 of the deformed portion 3A in the initial state reaching the vicinity of the narrowed portion. A protruding amount (length L) of 3A can be set. Therefore, the deformable portion 3A can enter the narrowed portion without excess or deficiency.

The ratio _L max _{/ L min} of the length _{L max} and length _{L min} is not particularly limited, for example, is preferably from 1.1 to 4, more preferably from 1.5 to 3 .

When the ratio L _max / L _min is within the above range, it is possible to prevent the wire diameter of the elongated wire 1A from becoming too thin and the penetrating force of the constricted portion from becoming poor. Moreover, there is an advantage that it is possible to prevent the penetration from becoming insufficient due to insufficient elongation or the penetration from being delayed.

  In the wire 1A, the expansion / contraction speed of the expansion / contraction actuator 4A can be controlled by changing the magnitude of the voltage applied between the electrodes 42a and 42b with time.

For example, when the applied voltage at which the length of the deforming portion 3A is L _max is V _max , when the voltage V _max is suddenly applied to the expansion / contraction actuator 4A (between the electrodes 42a and 42b), the deforming portion 3A is initially The time ΔT required to reach the extended state (length L _max ) from the state (length L _min ) is a predetermined time ΔT ₁ . On the other hand, when the voltage is gradually applied from zero to the voltage V _max to the expansion / contraction actuator 4A, the time ΔT required for the deformable portion 3A to reach the extended state from the initial state is a time ΔT longer than the predetermined time ΔT _{1. 2}

That is, if the expansion / contraction speed (extension speed) until the deformable portion 3A reaches the extended state from the initial state is (L _max −L _min ) / ΔT, the expansion speed is appropriately set by adjusting ΔT ( Adjustment).

  By such control, when the deformed portion 3A in the initial state is in the expanded state, for example, the deformed portion 3A is prevented from excessively projecting and protruding from the narrowed portion.

  In addition, by such control, it is possible to change the extension speed (extension speed) when the initial state becomes the extension state and the contraction speed (extension speed) when the extension state changes to the initial state. For example, when the deformation unit 3A suddenly changes from the extended state to the initial state, when the influence on the blood vessel is small, the contraction speed (expansion / contraction speed) may be set larger than the expansion speed. Thereby, it can transfer to the following process (for example, operation of wire 1A) rapidly.

  The method of changing the magnitude of the applied voltage between the electrodes 42a and 42b with time is not particularly limited. For example, a variable resistor is provided between the expansion / contraction actuator 4A and the power source, and the variable resistor And a method of changing the electrical resistance with time (gradually). Further, the operation is not limited to the artificial operation as described above, and the magnitude of the applied voltage may be controlled by computer control, for example.

  In the wire 1A configured as described above, when the deformable portion 3A in the initial state reaches the vicinity of the constriction portion, the expansion / contraction actuator 4A extends, so that the deformation portion 3A projects toward the constriction portion, and the constriction It is possible to enter the part surely. Thereby, a constriction part can be penetrated reliably.

  The method for manufacturing the wire 1A is not particularly limited, and examples thereof include the following methods.

  The wire 1 </ b> A of the present embodiment is manufactured separately from the three parts of the wire main body 2 </ b> A, the deformed portion 3 </ b> A, and the tip soft tip 32.

  The wire body 2A can be manufactured by a conventionally known method for manufacturing a medical guide wire. For example, it can be manufactured by coating the core wire 25 and the lead wire 44a with a coating resin, and further coating the lead wire 44b with the coating resin. In order to prevent disconnection due to the bending of the guide wire, the lead wire 44b may be spirally disposed around the lead wire 44a in a non-contact (insulated) state. If necessary, a joining platinum chip or the like may be joined to the tip of the lead wire in order to join the electrode of the deformable portion 3A.

  Next, in order to form the electrodes 42a and 42b, the deformed portion 3A has a thermoplastic elastomer electroactive polymer mixed with silver, platinum, carbon black or the like (preferably the same as the electroactive polymer 21 used), The thermoplastic elastomer electroactive polymer can be produced by multilayer extrusion and cutting to the required length.

  Further, the tip soft tip 32 can be made of a thermoplastic elastomer (preferably the same as the electroactive polymer 21 to be used) by hot compression molding, injection molding or extrusion molding.

The bonding between the wire main body 2A and the deforming portion 3A and the bonding between the deforming portion 3A and the tip soft tip 32 can be performed by high-frequency fusion using a mold or the like. In that case, it is necessary to join the front-end | tip part of the lead wires 44a and 44b of the wire main body 2A, and the electrodes 42a and 42b of the deformation | transformation part 3A.
The wire 1A can be manufactured through such steps.

  In the configuration shown in FIG. 1 (also in FIG. 2), the electrode 42a is connected to the positive electrode of the power source, and the electrode 42b is connected to the negative electrode of the power source. The electrode 42b may be connected to the positive electrode of the power source.

  Moreover, although the wire main body 2A is solid in the structure shown in FIG. 1, it is not limited to this, For example, a hollow may be sufficient.

  Further, the number of electrodes installed is not limited to two, and may be three or more. When the number of electrodes is three or more, these electrodes are arranged concentrically. Adjacent electrodes are connected to different electrodes of the power source. For example, when a predetermined electrode is connected to the positive electrode of the power source, the electrode adjacent to the predetermined electrode is connected to the negative electrode of the power source.

  Thus, by changing the number of electrodes, the degree of expansion / contraction of the expansion / contraction actuator can be set as appropriate.

  The outer peripheral surface 22 of the wire body 2A may be provided with an elastic film (stretchable film) made of an elastic material (stretchable material).

  Examples of the elastic material constituting the elastic film include various rubber materials such as natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, butyl rubber, silicone rubber, fluororubber, and acrylic rubber, polyurethane, and polyester. And various thermoplastic elastomers such as polyamides.

  Moreover, the outer peripheral surface 22 of 2 A of wire main bodies may be provided with the surface layer (not shown) comprised with the hydrophilic material. As a result, the hydrophilic material is wetted and lubricity is generated, and the frictional resistance (sliding resistance) of the outer peripheral surface 22 of the wire body 2A is reduced, so that the inside of a body cavity such as a blood vessel or a device such as a sheath or guiding catheter is reduced. Thus, the slidability of the wire 1A is improved. Therefore, the operability at the time of operations such as advancement / retraction and rotation of the wire 1A is improved.

  Examples of hydrophilic materials include cellulose-based polymer materials, polyethylene oxide-based polymer materials, and maleic anhydride-based polymer materials (for example, maleic anhydride copolymers such as methyl vinyl ether-maleic anhydride copolymer). Acrylamide polymer substances (for example, polyacrylamide, polyglycidyl methacrylate-dimethylacrylamide (PGMA-DMAA) block copolymer), water-soluble nylon, polyvinyl alcohol, polyvinylpyrrolidone and the like.

  Such a hydrophilic material often exhibits lubricity by wetting (water absorption), and reduces frictional resistance (sliding resistance) between a body cavity such as a blood vessel into which the wire 1A is inserted and the inner wall surface of the instrument. . Thereby, the slidability of the wire 1A is improved, and the operability of the wire 1A becomes better.

  Further, a member (for example, a ring-shaped member) or a material (for example, a filler) having radiopacity may be embedded in at least the vicinity of the tip 31 of the deformable portion 3A. Thereby, the tip 31 of the deformation | transformation part 3A can be confirmed reliably under X-ray fluoroscopy.

Second Embodiment
FIG. 3 is a longitudinal sectional view showing an embodiment (second embodiment) when the medical device of the present invention is applied to a wire ((a) is a state in which the electrodes are energized, and (b) is a state between the electrodes. 4 is a perspective view of the expansion / contraction actuator of the medical device (wire) in FIG. In the following, for convenience of explanation, the right side in FIGS. 3 and 4 is referred to as “base end”, and the left side is referred to as “tip”.

  Hereinafter, the second embodiment of the medical device of the present invention will be described with reference to these drawings, but the description will focus on the differences from the above-described embodiment, and the description of the same matters will be omitted.

  This embodiment is substantially the same as the first embodiment except that the configurations of the wire body and the telescopic actuator are different.

  A wire 1B shown in FIG. 3 includes a wire main body (linear body) 2B and an expansion / contraction actuator 4B embedded in the distal end portion of the wire main body 2B.

  A core wire (core material) 23 is embedded in the wire main body 2B on the base end side with respect to the expansion / contraction actuator 4B.

  The core wire 23 includes a tapered portion (outer diameter gradually decreasing portion) 231 and an outer diameter constant portion 232 that is integrally formed on the proximal end side of the tapered portion 231.

The taper portion 231 is a portion whose outer diameter gradually decreases in the distal direction.
The outer diameter constant portion 232 is a portion where the outer diameter is formed substantially constant along the longitudinal direction of the core wire 23.

  In addition, it does not specifically limit as a constituent material of the core wire 23, For example, Ni-Ti system alloy, Cu-Zn alloy, Ni-Al alloy, stainless steel (for example, SUS304, SUS303, SUS316, SUS316L, SUS316J1, SUS316J1L, Various metal materials such as SUS405, SUS430, SUS434, SUS444, SUS429, SUS430F, SUS302, all kinds of SUS), piano wire, cobalt-based alloy, etc. can be used. Including superelastic alloys). More preferably, it is a superelastic alloy.

  Moreover, the outer peripheral surface 22 and the front end surface of the wire body 2B are provided with a surface layer 24 made of a hydrophilic material. As a result, the hydrophilic material is moistened and lubricated, the friction (sliding resistance) between the outer peripheral surface 22 and the distal end surface of the wire body 2B is reduced, and the body cavity such as a blood vessel, sheath, guiding catheter, etc. The slidability of the wire 1B is improved in the instrument. Therefore, the operability at the time of operations such as advancement / retraction and rotation of the wire 1B is improved.

  As this hydrophilic material, for example, the materials mentioned in the description of the surface layer of the wire body 2A of the first embodiment can be used.

  A portion where the expansion / contraction actuator 4B is embedded in the distal end portion of the wire body 2B (hereinafter referred to as “deformation portion 3B”) is a portion that expands and contracts in the longitudinal direction of the wire body 2B.

  As shown in FIGS. 3 and 4, the expansion / contraction actuator 4B of the deformable portion 3B is a multilayer structure in which six layered electroactive polymers 41b and a total of seven layered electrodes 42c and 42d are alternately stacked. It consists of As a result, the expansion / contraction actuator 4B can efficiently expand and contract.

  As shown in FIG. 4, each electrode 42c is connected to a positive electrode of a power source (not shown) via a lead wire 44c embedded in the wire body 2B. Each electrode 42d is connected to a negative electrode of a power source (not shown) via a lead wire 44d embedded in the wire body 2B.

Next, the operation of the wire 1B configured as described above will be described.
In the state shown in FIG. 3A, that is, in the initial state, a voltage is applied between the electrodes 42c and 42d of the telescopic actuator 4B. By applying the voltage, the positive charge is uniformly distributed in the vicinity of the end surface 413 on the electrode 42c side of the electroactive polymer 41b located between the electrodes 42c and 42d, that is, charged positively. Also, the negative charge is uniformly distributed around the end surface 414 of the electroactive polymer 41b on the electrode 42d side, that is, it is negatively charged.

Thereby, in each electroactive polymer 41b, the positively charged end surface 413 and the negatively charged end surface 414 attract each other. As a result, the distance (thickness t ₁ ) between the end surface 413 and the end surface 414 decreases, and the expansion / contraction actuator 4B contracts.

  In the deformed portion 3B in the initial state, when the application of the voltage between the electrodes 42c and 42d is stopped, the inquiry between the end surface 413 and the end surface 414 is eliminated. Thereby, the shape of the electroactive polymer 41b is restored, and thus the deformed portion 3B is in the state shown in FIG.

Further, since the volume of each electroactive polymer 41b is constant, in a stretched state, the shape of the electroactive polymer 41b is restored, i.e., the thickness t ₁ is increased correspondingly, the outer diameter of the deformable section 3A, initial The diameter is reduced from the outer diameter of the deformed portion 3A in the state.

  In the wire 1B configured as described above, when the deformable portion 3B in the initial state reaches the vicinity of the constriction portion, the expansion / contraction actuator 4B extends, so that the deformation portion 3B protrudes toward the constriction portion, and the constriction It is possible to enter the part surely. Thereby, a constriction part can be penetrated reliably.

  Similarly to the expansion / contraction actuator 4A, the expansion / contraction actuator 4B is configured to be able to set the degree of expansion / contraction according to the magnitude of the voltage applied between the electrodes 42c and 42d.

  Further, in the wire 1B, by changing the magnitude of the applied voltage between the electrodes 42c and 42d with time, the expansion / contraction speed of the expansion / contraction actuator 4B can be controlled in the same manner as the wire 1A.

  The method of changing the magnitude of the applied voltage between the electrodes 42c and 42d with time is not particularly limited, and for example, the method described in the first embodiment can be used.

  Moreover, it does not specifically limit as a method to manufacture the wire 1B, For example, the following methods are mentioned.

  First, an electroactive polymer layer is prepared by hot compression molding, injection molding, dipping in a base material, coating, or the like.

  Next, an electrode layer is formed on one surface of the electroactive polymer layer by vapor deposition such as vapor deposition or sputtering, or by applying or dipping an elastomer material mixed with a conductive substance.

Further, an electrode layer is formed on the other surface of the electroactive polymer layer in the same manner as described above.
If necessary, an electroactive polymer layer and an electrode layer can be formed sequentially to form a laminate.
The actuator laminate is formed into a required shape by cutting or the like.

  After connecting the lead wires 44c and 44d of the wire main body 2B and the electrodes 42c and 42d of the actuator laminate, the actuator laminate is coated with an electroactive polymer as necessary, and a high-frequency fusion method using a die The wire body 2B and the actuator laminated body are joined by, for example, the above.

Further, if necessary, the outermost layer is coated.
The wire 1B can be manufactured through the steps as described above.

  In the configuration shown in FIG. 4, the electrode 42c is connected to the positive electrode of the power source and the electrode 42d is connected to the negative electrode of the power source. However, the present invention is not limited to this, and the electrode 42c is connected to the negative electrode of the power source. The electrode 42d may be connected to the positive electrode of the power source.

  Moreover, as a constituent material of the electroactive polymer 41b, the materials mentioned in the description of the electroactive polymer 21 of the first embodiment can be used.

  Further, as the constituent materials of the electrodes 42c and 42d, the materials mentioned in the description of the electrodes 42a and 42b of the first embodiment can be used.

  Further, the number of layers of the electroactive polymer 41b of the expansion / contraction actuator 4B is not limited to six layers, and may be one layer, two layers, three layers, four layers, five layers, seven layers or more, for example. Good.

  The number of stacked electrodes of the expansion / contraction actuator 4B is not limited to seven layers, and may be two layers, three layers, four layers, five layers, six layers, eight layers or more, for example.

Each electroactive polymer 41b is not limited to the thickness t ₂ are all equal, for example, may be different in thickness t ₂ are all thickness between a portion of the electroactive polymer 41b and t ₂ may be the same.

<Third Embodiment>
FIG. 5 is a longitudinal section showing an embodiment (third embodiment) when the medical device of the present invention is applied to a catheter ((a) is a state where no current is applied between the electrodes, and (b) is a state where current is applied between the electrodes. 6 is a perspective view of the telescopic actuator of the medical device (catheter) in FIG.

  In the following, for convenience of explanation, the right side in FIG. 5 is referred to as “base end” and the left side is referred to as “tip”. In FIG. 5, lead wires connected to the electrodes of the telescopic actuator are omitted.

  Hereinafter, the third embodiment of the medical device of the present invention will be described with reference to these drawings. However, the difference from the above-described embodiment will be mainly described, and the description of the same matters will be omitted.

  In this embodiment, the medical device of the present invention is applied to a catheter used by being inserted into a living body. This catheter 5A is, for example, a stenotic part or an obstructed part (hereinafter referred to as a stenotic part and an occluded part) caused by a lesion in a lumen in a living body such as a blood vessel, a bile duct, a trachea, an esophagus, or a urethra (hereinafter represented by “blood vessel”). Are collectively referred to simply as “stenosis”).

  A catheter 5A shown in FIG. 5 has a flexible long catheter body (linear body) 6A and an expansion / contraction actuator 4C embedded in the distal end portion of the catheter body 6A.

  As shown in FIG. 5, a lumen (lumen) 61 is formed in the catheter body 6A over almost the entire length of the catheter body 6A. The lumen 61 is open at the tip. Such a lumen 61 functions as, for example, a flow path for transferring a liquid such as a contrast medium, a drug solution, or a cleaning liquid, or a guide path for guiding a narrower medical guide wire, a treatment catheter, or the like.

  The distal end opening 62 of the catheter body 6A can eject the liquid in the lumen 61 to the outside, and can project the distal end of the guided catheter.

  The distal end opening 62 of the catheter body 6A has a rounded edge 621. Thereby, when the catheter 5A is inserted into a living body such as a blood vessel, the insertion can be performed more smoothly, and damage to the inner wall of the blood vessel can be prevented. That is, the operability and safety of insertion of the catheter 5A are improved.

  The catheter body 6A is preferably composed of a laminate of a plurality of layers. That is, as shown in FIG. 2, the catheter body 6 </ b> A is formed by laminating an inner layer 63 and an outer layer 64.

  Further, a part of the distal end portion 641 of the outer layer 64 protrudes from the distal end opening 631 of the inner layer 63 toward the distal end direction.

  Examples of the constituent material for the inner layer 63 and the outer layer 64 include polyolefins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, and cross-linked ethylene-vinyl acetate copolymer, polyvinyl chloride, and polyester. (PET, PBT, PEN, etc.), polyamide, polyimide, polyurethane, polystyrene, polycarbonate, fluorine resin (polytetrafluoroethylene, etc.), silicone resin, silicone rubber, and other various elastomers (for example, polyamide, polyester, etc.) Thermoplastic elastomers) and the like, and one or more of them can be used in combination. The constituent materials of the inner layer 63 and the outer layer 64 may be the same or different.

  When the constituent materials of the inner layer 63 and the outer layer 64 are different, materials having different flexibility (rigidity) can be used.

  The inner layer 63 is made of a material having a relatively high sliding life such as polytetrafluoroethylene, fluorinated ethylene propylene (FEP), or high density polyethylene, and the outer layer 64 is made of, for example, polyurethane, polyamide, polyester, or the like. The guide wire within the lumen 61 of the catheter body 6A is improved in slidability when the catheter body 6A is inserted into the blood vessel. The insertion operation can be performed more smoothly and reliably.

  Further, a hydrophilic layer (surface layer) 65 made of a hydrophilic material is provided on the outer peripheral surface 642, the distal end surface 643, and the inner peripheral surface 644 of the distal end portion 641 of the outer layer 64.

  As a result, the hydrophilic material is wetted to cause lubrication, and the friction (sliding resistance) of the outer peripheral surface 642, the distal end surface 643 and the inner peripheral surface 644 of the outer layer 64 is reduced. The slidability of the wire 1B is improved in a device such as a guiding catheter, or the slidability of the guide wire on the inner peripheral surface 644 is improved. Therefore, the operability when operating the catheter 5A is improved.

  As this hydrophilic material, for example, the materials mentioned in the description of the surface layer of the wire body 2A of the first embodiment can be used.

  The site where the telescopic actuator 4C is embedded in the distal end portion 641 of the catheter body 6A (outer layer 64) (hereinafter referred to as “deformed portion 3C”) is a site that expands and contracts in the longitudinal direction of the catheter body 6A.

As shown in FIGS. 5 and 6, the expansion / contraction actuator 4C of the deformable portion 3C is configured by a multilayer structure in which layered electroactive polymers 41c and layered two electrodes 42e and 42f are alternately stacked. ing. That is, the expansion / contraction actuator 4C includes a ring-shaped electroactive polymer 41c, a layered electrode 42e provided on the outer peripheral surface 411 of the electroactive polymer 41c, and a layered configuration provided on the inner peripheral surface 412 of the electroactive polymer 41c. Electrode 42f.
With such a configuration, the expansion / contraction actuator 4C can efficiently expand and contract.

  As shown in FIG. 6, the electrode 42e is connected to a positive electrode of a power source (not shown) through a lead wire 44e. The electrode 42f is connected to a negative electrode of a power source (not shown) via a lead wire 44f.

Next, the operation of the catheter 5A configured as described above will be described.
By applying a voltage between the electrodes 42e and 42f of the expansion / contraction actuator 4C in the initial state (the state shown in FIG. 5A), negative charges are uniformly distributed in the vicinity of the outer peripheral surface 411 of the electroactive polymer 41c. That is, it is negatively charged. Further, near the inner peripheral surface 412 of the electroactive polymer 41c, positive charges are uniformly distributed, that is, positively charged.

Thereby, in the electroactive polymer 41c, the negatively charged outer peripheral surface 411 and the positively charged inner peripheral surface 412 attract each other. As a result, the distance (thickness t ₃ ) between the outer peripheral surface 411 and the inner peripheral surface 412 decreases.

Here, the volume of the electroactive polymer 41c is constant, the partial thickness t ₃ is reduced, the length L of the deformation portion 3C is increased, to the deformable portion 3C is extended state (see FIG. 5 (b) State).

  In the extended deformed portion 3C, when the application of the voltage between the electrodes 42e and 42f is stopped, the inquiry between the outer peripheral surface 411 and the inner peripheral surface 412 is eliminated. Thereby, the shape of the electroactive polymer 41c is restored, and thus the deformed portion 3C is in the initial state.

  In the catheter 5A configured as described above, when the deformable portion 3C in the initial state reaches the vicinity of the stenosis portion, the expansion / contraction actuator 4C extends, so that the deformation portion 3C protrudes toward the stenosis portion, and the stenosis It is possible to enter the part surely. Thereby, a constriction part can be penetrated reliably.

  The expansion / contraction actuator 4C is configured to set the degree of expansion / contraction, similar to the expansion / contraction actuator 4A, depending on the magnitude of the voltage applied between the electrodes 42e and 42f.

  In the catheter 5A, the expansion / contraction speed of the expansion / contraction actuator 4C can be controlled in the same manner as the expansion / contraction actuator 4A by changing the magnitude of the applied voltage between the electrodes 42e and 42f with time.

  By such control, when the deformed portion 3C in the initial state is in the extended state, for example, the deformable portion 3C is prevented from excessively projecting and protruding from the narrowed portion.

  In addition, by such control, it is possible to change the extension speed (extension speed) when the initial state becomes the extension state and the contraction speed (extension speed) when the extension state changes to the initial state. For example, when the deformation portion 3C suddenly changes from the extended state to the initial state, when the influence on the blood vessel is small, the contraction speed (expansion / contraction speed) may be set larger than the expansion speed. Thereby, it can transfer to the following process (for example, operation of catheter 5A) rapidly.

  The method for changing the magnitude of the applied voltage between the electrodes 42e and 42f with time is not particularly limited, and for example, the method described in the first embodiment can be used.

  Further, the catheter body 6A is not limited to being configured by a laminated body, and may be configured by, for example, a single layer.

  In the configuration shown in FIG. 6, the electrode 42e is connected to the positive electrode of the power source and the electrode 42f is connected to the negative electrode of the power source. However, the present invention is not limited to this, and the electrode 42e is connected to the negative electrode of the power source. The electrode 42f may be connected to the positive electrode of the power source.

  Moreover, as a constituent material of the electroactive polymer 41c, the materials mentioned in the description of the electroactive polymer 21 of the first embodiment can be used.

  Further, as the constituent materials of the electrodes 42e and 42f, the materials described in the description of the electrodes 42a and 42b of the first embodiment can be used.

  The expansion / contraction actuator 4C includes one layer of electroactive polymer 41c and two layers of electrodes 42e and 42f, but is not limited thereto. For example, two or more layers of electroactive polymer 41c; It may be composed of three or more layers of electrodes 42e and 42f.

<Fourth embodiment>
FIG. 7 is a longitudinal sectional view showing an embodiment (fourth embodiment) when the medical device of the present invention is applied to a catheter ((a) is a state in which the electrodes are not energized, and (b) is a state between the electrodes. 8 is a perspective view of the actuator for fixing the medical device (catheter) shown in FIG. 7, and FIG. 9 is a portion schematically showing the use state of the medical device (catheter) shown in FIG. It is a longitudinal cross-sectional view.

  Hereinafter, for convenience of explanation, the right side in FIGS. 7 to 9 is referred to as “base end”, and the left side is referred to as “tip”. In FIG. 7, lead wires connected to the respective electrodes of the telescopic actuator and lead wires connected to the respective electrodes of the fixing actuator are omitted. Further, in FIG. 7, an engaging member as a fixing auxiliary means is omitted.

  Hereinafter, the fourth embodiment of the medical device of the present invention will be described with reference to these drawings. However, the difference from the above-described embodiment will be mainly described, and the description of the same matters will be omitted.

  This embodiment is the same as the third embodiment except that the catheter body is provided with a fixing portion.

  A catheter 5B shown in FIG. 7 has an anchoring actuator 8 embedded in a location proximal to the deformed portion 3C of the catheter body 6A.

  The portion where the fixing actuator 8 is embedded (hereinafter referred to as “fixing portion (fixing deformation portion) 7”) fixes the catheter body 6A to the wall 20 of the blood vessel into which the catheter body 6A is inserted. (Refer to FIG. 7B and FIG. 9B).

  As shown in FIGS. 7 and 8, the fixing actuator 8 has three electroactive polymers 81 that are deformed by energization, and a total of four electrodes 82a and 82b for energizing each electroactive polymer 81. Yes.

  Each electroactive polymer 81 has a layer shape, and each electrode 82 a and 82 b also has a layer shape in the same manner as each electroactive polymer 81. In the fixing actuator 8, the electroactive polymer 81 and the electrodes 82 a and 82 b are alternately stacked, and the fixing actuator 8 is formed of a multilayer structure.

  As shown in FIG. 8, each electrode 82a is connected to a positive electrode of a power source (not shown) via a lead wire 44g. The electrode 82b is connected to a negative electrode of a power supply (not shown) via a lead wire 44h.

  Next, the operation of the fixing portion 7 (fixing actuator 8) configured as described above will be described.

  By applying a voltage between the electrodes 82a and 82b of the fixing actuator 8 in the state shown in FIG. 7A (hereinafter, this state is referred to as an “initial state”), the electrode 82a side of each electroactive polymer 81 is applied. Near the end surface 811, negative charges are uniformly distributed, that is, negatively charged. Further, near the end surface 812 of the electroactive polymer 81 on the electrode 82b side, positive charges are uniformly distributed, that is, positively charged.

Thereby, in the electroactive polymer 81, the negatively charged end surface 811 attracts the positively charged end surface 812. As a result, the distance (thickness t ₄ ) between the end surface 811 and the end surface 812 decreases.

Here, since the volume of the electroactive polymer 81 is constant, the outer diameter φD of the fixing portion 7 increases as the thickness t ₄ decreases, and the fixing portion 7 is in the state shown in FIG. Hereinafter, this state is referred to as an “expanded state”.

  Further, in the fixed portion 7 in the expanded state, when the application of the voltage between the electrodes 82a and 82b is stopped, the inquiry between the end surface 811 and the end surface 812 is eliminated. As a result, the shape of each electroactive polymer 81 is restored, that is, the outer diameter φD of the fixing portion 7 is reduced, so that the fixing portion 7 is in the initial state.

  As shown in FIG. 7 (b), the deformed portion 3C in the initial state is set in the expanded state with the catheter 5B fixed to the wall portion 20 of the blood vessel by the fixed portion 7 in the expanded state. At this time, the deforming portion 3C enters the constricted portion, but is pressed from the constricted portion to the proximal end side.

  However, since the catheter 5B is fixed with respect to the wall portion 20, it is prevented from being pushed back to the proximal end side by being pressed from the narrowed portion. Thereby, the deformation | transformation part 3C of an expansion | extension state can penetrate reliably a constriction part.

  Moreover, since the fixing | fixed part 7 is comprised so that it may deform | transform by electrical operation, it is excellent in the responsiveness and reproducibility.

  In the catheter 5B, the telescopic actuator 4C and the fixing actuator 8 are preferably configured to operate independently.

  Thereby, the expansion / contraction actuator 4C and the fixing actuator 8 can be operated at an arbitrary timing. For example, when the deformable portion 3C is in the extended state and penetrates the constricted portion, the fixing actuator 8 is actuated in advance, and the catheter 5B can be fixed by the fixing portion 7.

  The fixing actuator 8 is configured such that the degree of expansion can be set according to the magnitude of the voltage applied between the electrodes 82a and 82b.

In other words, when the applied voltage is set to the maximum within the allowable voltage range that can be applied to the fixing actuator 8, the fixing portion 8 expands to the maximum, and the outer diameter φD. Becomes the maximum (φD _max ). Further, when the voltage to be applied is set to the minimum, that is, zero, the fixing unit 7 does not expand the fixing actuator 8, and the outer diameter φD is minimum (φD _min ), that is, the initial state. In addition, when the voltage to be applied is set to an arbitrary magnitude between the maximum and minimum, the fixed portion 7 has an outer diameter φD between the outer diameter φD _max and the outer diameter φD _min .

  Since the degree of expansion of the fixing actuator 8 can be set in this way, it is possible to perform fixing with high safety and no excess or deficiency depending on the case.

  In the catheter 5B, the expansion speed of the fixing actuator 8 can be controlled by changing the magnitude of the applied voltage between the electrodes 82a and 82b with time.

For example, when the applied voltage at which the outer diameter of the fixed portion 7 is φD _max is V _max , when the voltage V _max is suddenly applied to the fixing actuator 8 (between the electrodes 82a and 82b), the fixed portion 7 The time ΔT required to reach the expanded state (outer diameter φD _max ) from the initial state (outer diameter φD _min ) is a predetermined time ΔT ₁ . On the other hand, when applying gradually voltage from zero to the fixed actuator 8 to a voltage V _max, the time [Delta] T of the fixing portion 7 is required to reach from the initial state to the expanded state, the time longer than the predetermined time [Delta] T ₁ [Delta] T ₂

That is, if the expansion speed until the fixed portion 7 reaches the expanded state from the initial state is (φD _max −φD _min ) / ΔT, the expansion speed is appropriately set (adjusted) by adjusting ΔT. Can do.

  By such control, when the initial fixed portion 7 is in the expanded state, the catheter 5B can be fixed to the blood vessel wall portion 20 with high safety and without excess or deficiency.

  In addition, by such control, it is possible to change the expansion speed when changing from the initial state to the expanded state and the contraction speed (expansion speed) when changing from the expanded state to the initial state. For example, if the influence on the blood vessel is small when the fixing unit 7 suddenly changes from the expanded state to the initial state, the contraction speed may be set larger than the expansion speed. Thereby, it can transfer to the following process (for example, operation of catheter 5B) rapidly.

  The method for changing the magnitude of the applied voltage between the electrodes 82a and 82b with time is not particularly limited. For example, a variable resistor is provided between the fixing actuator 8 and the power source, and the variable resistor is provided. And a method of changing the electrical resistance with time (gradually). Further, the operation is not limited to the artificial operation as described above, and the magnitude of the applied voltage may be controlled by computer control, for example.

  Further, as shown in FIG. 9, the fixing portion 7 is provided with an engaging member 71 as a fixing auxiliary means for assisting the fixing.

  The engaging member 71 is made of an elastic material. The engaging member 71 has a cylindrical shape, and a distal end portion 711 thereof is joined to the outer peripheral surface 66 of the catheter body 6A.

  Further, the engaging member 71 is in close contact with the outer peripheral surface 66 of the catheter main body 6A when the fixing portion 7 is in the initial state.

  Further, as shown in FIG. 9B, when the fixing portion 7 is in the expanded state, the inner peripheral surface of the engaging member 71 is pressed against the surface 72 (outer peripheral surface 66) of the fixing portion 7, The proximal end 712 engages the blood vessel wall 20 (inner surface of the body cavity). Thereby, the catheter 5 </ b> B is more reliably fixed to the wall portion 20.

  The fixing auxiliary means is not limited to the one constituted by the engaging member 71. For example, the fixing portion 7 is provided with minute irregularities on the surface 72 of the fixing portion 7 that contacts the blood vessel wall portion 20. It may be. The catheter 5 </ b> B is more reliably fixed to the wall portion 20 by such fixing auxiliary means.

Next, an example of how to use the catheter 5B will be described with reference to FIG.
First, as shown in FIG. 9A, the catheter 5B and the guide wire 10 inserted into the lumen 61 are inserted into the blood vessel, and the guide wire 10 protruded from the distal end opening 62 of the catheter 5B. The distal end portion is inserted deeper (peripheral side) than the narrowed portion 201. That is, the guide wire 10 is in a state of being inserted through the narrowed portion 201. This operation can be performed more easily by using, for example, a micro guide wire having excellent lubricity as the guide wire 10.

  Next, in the state shown in FIG. 9A, the fixed portion 7 in the initial state is set in the expanded state. Thereby, the catheter 5 </ b> B is fixed to the wall portion 20. Further, when the fixing portion 7 is in the expanded state, the engaging member 71 is engaged with the wall portion 20, so that the fixing portion 7 is more reliably fixed.

  Next, in a state where the catheter 5B is fixed, the deformed portion 3C in the initial state is set in an expanded state. At this time, the deforming portion 3 </ b> C smoothly enters the narrowed portion 201 along the guide wire 10 and reliably penetrates the narrowed portion 201.

  In the configuration shown in FIG. 9B, the fixed portion 7 in the expanded state has the catheter 5B in contact with the wall portion 20, but is not limited to this, and the catheter 5B may be separated from the wall portion 20. Good.

  In the configuration shown in FIG. 8, the electrode 82a is connected to the positive electrode of the power source and the electrode 82b is connected to the negative electrode of the power source. However, the present invention is not limited to this, and the electrode 82a is connected to the negative electrode of the power source. The electrode 82b may be connected to the positive electrode of the power source.

  Moreover, as a constituent material of the electroactive polymer 81, the materials mentioned in the description of the electroactive polymer 21 of the first embodiment can be used.

  Further, as the constituent materials of the electrodes 82a and 82b, the materials described in the description of the electrodes 42a and 42b of the first embodiment can be used.

  Further, the number of layers of the electroactive polymer 41b of the fixing actuator 8 is not limited to three, and may be one, two, four, five, six or more, for example.

  Further, the number of stacked electrodes of the fixing actuator 8 is not limited to four, and may be two, three, five or more, for example.

In addition, the thickness t _{4 of} each electroactive polymer 81 is not limited to be equal. For example, the thickness t ₄ may all be different, or the thicknesses of some electroactive polymers 81 may be different. t ₄ may be the same.

  As described above, the medical device of the present invention has been described with respect to the illustrated embodiment. However, the present invention is not limited to this, and each component constituting the medical device has any configuration that can exhibit the same function. Can be substituted. Moreover, arbitrary components may be added.

  The medical device of the present invention may be a combination of any two or more configurations (features) of the above embodiments.

  For example, you may provide the fixing | fixed part as described in the said 4th Embodiment in the wire of 1st Embodiment and 2nd Embodiment.

  Moreover, you may provide an electric charge distribution layer as described in the said 1st Embodiment in each electrode of the expansion-contraction actuator of 2nd Embodiment, 3rd Embodiment, and 4th Embodiment, respectively.

  Further, a charge distribution layer as described in the first embodiment may be provided on each electrode of the fixing actuator of the fourth embodiment.

The longitudinal cross-sectional view which shows embodiment (1st Embodiment) at the time of applying the medical device of this invention to a wire ((a) is the state which is not electrically connected between electrodes, (b) is the electricity between electrodes. State). It is the sectional view on the AA line in FIG. The longitudinal cross-sectional view which shows embodiment (2nd Embodiment) at the time of applying the medical device of this invention to a wire ((a) is the state in which between electrodes are energized, (b) is not energizing between electrodes. State). It is a perspective view of the actuator for expansion / contraction of the medical device (wire) in FIG. The longitudinal cross-sectional view which shows embodiment (3rd Embodiment) at the time of applying the medical device of this invention to a catheter ((a) is the state which is not electrically connected between electrodes, (b) is the electricity between electrodes. State). It is a perspective view of the actuator for expansion / contraction of the medical device (catheter) in FIG. The longitudinal cross-sectional view which shows embodiment (4th Embodiment) at the time of applying the medical device of this invention to a catheter ((a) is the state which is not electrically connected between electrodes, (b) is the electricity between electrodes. State). It is a perspective view of the actuator for fixation of the medical device (catheter) shown in FIG. It is a fragmentary longitudinal cross-sectional view which shows typically the use condition of the medical device (catheter) shown in FIG.

Explanation of symbols

1A, 1B wire 2A, 2B wire body (linear body)
21 electroactive polymer 22 outer peripheral surface 23 core wire (core material)
231 Tapered part 232 Constant outer diameter part 24 Surface layer 25 Core wire (core material)
3A, 3B, 3C Deformation part 31 Tip 32 Tip soft tip 4A, 4B, 4C Telescopic actuator 41a, 41b, 41c Electroactive polymer 411 Outer surface 412 Inner surface 413, 414 End surface 42a, 42b, 42c, 42d, 42e, 42f Electrode 421, 422 Tip 44a, 44b, 44c, 44d, 44e, 44f, 44g, 44h Lead wire 5A, 5B Catheter 6A Catheter body (linear body)
61 lumen (lumen)
62 End opening 621 Edge 63 Inner layer 631 End opening 64 Outer layer 641 End portion 642 Outer surface 643 End surface 644 Inner surface 65 Hydrophilic layer (surface layer)
66 Outer peripheral surface 7 Fixing part (fixing deformation part)
71 the engagement member 711 distal end 712 proximal end 72 surface 8 fixed actuator 81 electroactive polymer 811 end surfaces 82a, 82b electrodes 10 guide wire 20 wall portion 201 narrowing portion _{t 1, t 2, t 3} , t 4 thickness L, L _max , L _min length φD, φD _max , φD _min outer diameter

Claims (8)

A medical device used by being inserted into a living body,
A long linear body, and a deformed portion that is provided at the tip of the linear body and expands and contracts in the longitudinal direction of the linear body,
The deformable portion has an electroactive polymer that deforms when energized and at least two electrodes for energizing the electroactive polymer, and expands and contracts in the longitudinal direction of the linear body when energized between the electrodes. A medical device comprising a telescopic actuator that operates as described above.   The medical device according to claim 1, wherein the expansion / contraction actuator is configured by a multilayer structure in which layered electroactive polymers and layered electrodes are alternately stacked.   The medical device according to claim 1 or 2, wherein a degree of expansion / contraction of the expansion / contraction actuator can be set by a magnitude of a voltage applied between the electrodes of the expansion / contraction actuator.   4. The structure according to claim 1, wherein the expansion / contraction speed of the expansion / contraction actuator can be adjusted by changing the magnitude of the voltage applied between the electrodes of the expansion / contraction actuator over time. Medical tools.   Either of the Claims 1 thru | or 4 which has a fixing | fixed part for fixing the said linear body with respect to the body cavity in which the said linear body was inserted provided in the location of the base end side from the said deformation | transformation part of the said linear body. Medical device according to.   The medical device according to claim 5, wherein the fixing portion includes a fixing deformation portion that is deformed so that an outer diameter increases or decreases.   The fixing deformation portion has an electroactive polymer that is deformed by energization and at least two electrodes for energizing the electroactive polymer, and operates to expand by energizing between the electrodes. The medical device according to claim 6, further comprising an actuator.   The medical device according to any one of claims 5 to 7, wherein a fixing assisting means for assisting the fixing is provided in the fixing portion.

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