WO2021200368A1

WO2021200368A1 - Sensor-equipped catheter

Info

Publication number: WO2021200368A1
Application number: PCT/JP2021/011879
Authority: WO
Inventors: 貴史藤畑; 貴樹石田
Original assignee: 日本ゼオン株式会社
Priority date: 2020-03-30
Filing date: 2021-03-23
Publication date: 2021-10-07
Also published as: JPWO2021200368A1; CN115151293A; JP7505546B2; CN115151293B

Abstract

Provided is a sensor-equipped catheter that is capable of measuring external pressure (blood pressure) with high accuracy. This sensor-equipped catheter comprises a catheter tube 3, a pressure sensor 8, an optical fiber 9, and a distal tip 5 which is provided on a distal end of the catheter tube 3, and which has a through hole 56 through which the optical fiber 9 is inserted, the through hole 56 defining a sensor accommodation space that accommodates the pressure sensor 8. The distal tip 5 includes: a side insertion hole 54 which is used as an injection hole of a pressure transmitting substance into the sensor accommodation space, communicates with the sensor accommodation space, and opens at an outer circumferential surface of the distal tip 5; and a distal end insertion hole 55 which is used as a pressure obtaining hole for measuring external pressure, communicates with the sensor accommodation space, opens at a distal end of the distal tip 5, and has an opening 55a having a diameter smaller than the dimension of the pressure sensor 8. An opening 54a of the side insertion hole 54 is covered by a resin film 11 on the outer circumferential surface side of the distal tip 5.

Description

Sensor-mounted catheter

The present invention relates to a sensor-mounted catheter in which a pressure sensor is mounted on a tip.

In recent years, catheters have been used for various treatments and tests in the medical field. For example, as a treatment for hypocardiac function, the IABP (IABP: Intra-Aortic Balloon Pumping) method, in which a balloon catheter is inserted into the aorta and the balloon is expanded and contracted according to the heartbeat to assist the cardiac function. It has been known.

As an intra-aortic balloon catheter used in the IABP method, a pressure sensor that detects pressure using light is attached to the distal end of the balloon catheter, and the detected blood pressure signal is transmitted near the balloon catheter via an optical fiber. A sensor-mounted catheter that transmits to the position has been proposed (see, for example, Patent Document 1 below).

The catheter described in Patent Document 1 has a tip, and has a sensor accommodating hole for arranging a pressure sensor and a through hole for inserting an optical fiber connected to the pressure sensor inside. It is formed. In this catheter, a short tube or through-hole wall and a plug member define a filling space in the sensor accommodating hole in which a gel-like substance, which is a pressure transmitter, is filled. By filling the filling space with a gel-like substance through the distal end opening of the through hole, the circumference of the pressure sensor is filled with the gel-like substance, and the distal end opening of the through hole is closed with the tip partition membrane. The filling space is sealed. That is, the outside and the filling space are connected only through the distal end opening of the through hole, and the gel-like substance is filled in the filling space through the distal end opening.

Japanese Unexamined Patent Publication No. 2010-233883

However, in the catheter described in Patent Document 1, the outside and the filling space are connected only through the distal end opening of the through hole, and the gel-like substance is filled in the filling space from the distal end opening. Therefore, since there is no passage for air to escape in the filling space when the gel-like substance is filled, air bubbles (voids) remain in the filling space, and the pressure sensor cannot be reliably covered with the gel-like substance. There is a problem that the measurement accuracy is lowered. Further, since the distal end opening of the through hole is blocked by the distal partition wall membrane, the pressure sensor is placed in the sealed filling space. Although the external pressure (blood pressure) is transmitted to the gel-like substance in the filling space via the distal partition membrane, the external pressure (blood pressure) cannot be sufficiently and accurately detected due to the intervention of the distal partition membrane, and the pressure sensor There is a problem that the measurement accuracy of

The present invention has been made in view of the above problems, and an object of the present invention is to provide a catheter capable of measuring external pressure (blood pressure) with high accuracy.

In order to achieve the above object, the sensor-mounted catheter according to the present invention
Catheter tube and
A pressure sensor that can measure pressure using light,
The optical fiber connected to the pressure sensor and
It has a tip tip provided at the distal end of the catheter tube and formed with a through hole through which the optical fiber is inserted and a sensor accommodation space for accommodating the pressure sensor is defined.
The tip is used as an injection hole for a pressure transmitting substance into the sensor accommodating space, and has a side insertion hole that communicates with the sensor accommodating space and opens on the outer peripheral surface of the tip tip, and external pressure. Used as a pressure collection hole for measurement, it communicates with the sensor accommodation space and opens at the distal end of the tip, and has an opening with a diameter smaller than the outer diameter of the pressure sensor. Holes are formed,
The opening of the lateral insertion hole is covered with a resin film on the outer peripheral surface side of the tip.

According to this configuration, the lateral insertion hole and the distal end insertion hole communicate with the sensor accommodation space filled with the pressure transmitting material, and when the pressure transmitting material is injected through the lateral insertion hole, the sensor is accommodated. The air in the space escapes from the distal end insertion hole so that no air bubbles (voids) remain in the sensor accommodation space, and the pressure sensor can be reliably covered with the pressure transmitter to improve the measurement accuracy of the pressure sensor. Become.

In addition, while the lateral insertion hole used for injecting the pressure transmitting substance is covered with a resin film to close it, the distal end insertion hole used as a pressure collection hole for measuring external pressure (blood pressure) is not blocked. Since the configuration can be opened to the outside, the pressure sensor can sufficiently and surely detect the external pressure (blood pressure), and the measurement accuracy of the pressure sensor can be improved.

Further, the distal end insertion hole has an opening having a diameter smaller than the outer diameter of the pressure sensor, for example, when the pressure sensor is about to flow out from the distal end insertion hole due to a broken optical fiber or the like. Even if the pressure sensor is present, the pressure sensor cannot pass through the distal end insertion hole, and the pressure sensor can be prevented from flowing out to the outside of the tip (inside the patient's body). Furthermore, since the opening of the distal end insertion hole is formed to be small, the amount of the pressure transmitter filled in the sensor accommodation space to the outside (inside the patient's body) can be reduced.

Further, in the sensor-mounted catheter according to the present invention, the distal end insertion hole may be formed in a tapered shape in which the distal end insertion hole narrows from the sensor accommodation space toward the opening.

According to this configuration, the distal end insertion hole can be formed so as to have an opening having a diameter smaller than the outer diameter of the pressure sensor, and the pressure sensor flows out of the tip (inside the patient's body). Can be reliably prevented.

Further, the sensor-mounted catheter according to the present invention is provided with a marker on the optical fiber that can be visually recognized from the lateral insertion hole when the pressure sensor is arranged at an appropriate position in the sensor accommodation space. You may.

According to this configuration, when arranging the pressure sensor in the sensor accommodation space, the position of the pressure sensor is grasped by checking the marker visible from the side insertion hole, and the pressure sensor is arranged at an appropriate position. become able to.

Further, the sensor-mounted catheter according to the present invention may be a substantially cylindrical member in which the marker is fixed to the optical fiber with the optical fiber inserted.

According to this configuration, the position of the pressure sensor can be grasped and the pressure sensor can be arranged at an appropriate position by visually recognizing the substantially cylindrical member that moves forward and backward together with the optical fiber and the pressure sensor in the through hole from the side insertion hole. become. Further, the fixing surface to which the curable resin such as an adhesive is fixed is secured by the surface of the substantially cylindrical member, and the fixing strength for fixing the optical fiber in the through hole can be increased.

Further, the sensor-mounted catheter according to the present invention is used for the tip of the tip as an injection hole of a curable resin into the through hole, and communicates with the through hole on the proximal end side of the sensor accommodating space. At the same time, a curable resin filling hole that opens on the outer peripheral surface of the tip may be formed.

According to this configuration, the curable resin can be directly filled in the through hole through the curable resin filling hole without adhering the curable resin to the pressure sensor, and the optical fiber is fixed in the through hole by the curable resin. become able to.

Further, in the sensor-mounted catheter according to the present invention, the opening of the curable resin filling hole may be covered with a resin film on the outer peripheral surface side of the tip.

According to this configuration, when another member such as a balloon portion is joined to the outer peripheral surface of the tip tip, its adhesiveness or heat fusion property can be improved.

It is a schematic cross-sectional view which shows an example of the sensor-mounted catheter in embodiment of this invention. It is a perspective view of the sensor-mounted catheter shown in FIG. It is a schematic cross-sectional view of the tip tip shown in FIG. It is a schematic cross-sectional view of the tip tip shown in FIG. 2, and is the figure which shows the initial process which concerns on the manufacture of the sensor-mounted catheter. It is a schematic cross-sectional view of the tip | tip shown in FIG. 2, and is the figure which shows the 2nd process which concerns on the manufacture of the sensor-mounted catheter. It is a schematic cross-sectional view of the tip | tip shown in FIG. 2, and is the figure which shows the 3rd process which concerns on the manufacture of the sensor-mounted catheter. It is a schematic cross-sectional view of the tip | tip shown in FIG. 2, and is the figure which shows the 4th process which concerns on the manufacture of the sensor-mounted catheter. It is a schematic cross-sectional view of the tip tip shown in FIG. 2, and is the figure which shows the 5th process which concerns on the manufacture of the sensor-mounted catheter.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this specification, the inside of the patient's body is the distal side, and the operator's hand side is the proximal side, with the operator as the reference.

The sensor-mounted catheter according to the present invention is a catheter in which a pressure sensor is mounted on a tip, and is particularly suitable as an intra-aortic balloon catheter used in the IABP method. In the following embodiment, the intra-aortic balloon catheter used in the IABP method as the sensor-mounted catheter according to the present invention will be described, but the sensor-mounted catheter according to the present invention has a coronary blood flow preliminary ratio (FFR: Fractional Flow Reserve). ) Suitable as a catheter used for measurement or other catheters.

FIG. 1 is a schematic cross-sectional view showing an example of a sensor-mounted catheter 1 according to an embodiment of the present invention.

As shown in FIG. 1, the sensor-mounted catheter 1 according to the embodiment of the present invention is an intra-aortic balloon catheter used in the IABP method, and has a balloon portion 4 that expands and contracts in accordance with the heartbeat. The balloon portion 4 is composed of a thin film having a film thickness of about 50 to 150 μm. The material of the thin film is not particularly limited, but is preferably a material having excellent bending fatigue resistance, and is made of, for example, polyurethane or the like.

The outer diameter and length of the balloon portion 4 are determined according to the inner volume of the balloon portion 4, which greatly affects the auxiliary effect of cardiac function, the inner diameter of the arterial blood vessel, and the like. The internal volume of the balloon portion 4 is not particularly limited, but is 20 to 50 cc, and the outer diameter of the balloon portion 4 is preferably 12 to 16 mm at the time of expansion, and the length is preferably 150 to 250 mm.

The distal end 40a of the balloon portion 4 is attached to the outer peripheral surface of the tip tip 5 by means such as heat fusion or adhesion. The tip 5 is formed with a wire insertion hole 50 that communicates in the axial direction, and the distal end portion of the inner tube 3 is inserted into the proximal end side thereof. The distal end of the inner tube 3 is attached to the proximal end of the tip tip 5 by means such as heat fusion or adhesion so that the wire passage 30 inside the inner tube 3 and the wire insertion hole 50 communicate with each other. It is connected.

The proximal end 40b of the balloon portion 4 is connected to the outer periphery of the distal end of the outer tube 2 via or directly via a contrast marker 6 made of a radiation opaque metal ring or the like. Through the pressure fluid conduction path 20 formed inside the outer pipe 2, the pressure fluid is introduced and led out to the inside of the balloon portion 4, and the balloon portion 4 expands and contracts. The balloon portion 4 and the outer tube 2 are connected by heat fusion or adhesion.

The inner tube (catheter tube) 3 extends axially inside the balloon portion 4 and the outer tube 2, and inside the inner tube (catheter tube) 3, a pressure fluid communication path 20 formed inside the balloon portion 4 and inside the outer tube 2. A wire passage 30 that does not communicate with is formed, and communicates with the secondary port 72 of the branch portion 7, which will be described later.

When the sensor-mounted catheter 1 is inserted into an artery, the balloon portion 4 in a contracted state is wound around the outer peripheral surface of the inner tube 3 located in the balloon portion 4. The wire passage 30 is used as a lumen through which a guide wire used for conveniently inserting the balloon portion 4 into the artery is inserted.

On the outside of the inner tube 3, the optical fiber 9 extends in the axial direction of the inner tube 3. More specifically, the optical fiber 9 extends along the outside (outer peripheral surface) of the inner tube 3 inside the outer tube 2 extending between the branch portion 7 and the proximal end 40b of the balloon portion 4. It extends straight in its axial direction. Further, the optical fiber 9 is spirally wound around the outer peripheral surface of the inner tube 3 inside the balloon portion 4 located between the proximal end portion 40b and the distal end portion 40a of the balloon portion 4. It extends in its axial direction. Further, the optical fiber 9 extends straight in the axial direction of the inner tube 3 inside the tip tip 5 where the distal end portion 40a of the balloon portion 4 is located (see FIG. 3). The balloon portion 4 in the contracted state described above is wound around the inner tube 3 around which the optical fiber 9 is spirally wound in the balloon portion 4.

As will be described in detail later, the distal end of the optical fiber 9 is fixed by the curable resin 14 in the tip 5 (see FIG. 6). Before the distal end of the optical fiber 9 is fixed in the tip tip 5, any portion located between the proximal end side and the distal end side of the optical fiber 9 is a fixing means such as an adhesive. It is not fixed to the outer peripheral surface of the inner tube 3 or the like, and only the proximal end side and the distal end side of the optical fiber 9 are fixed to the tertiary port 73 and the pressure sensor 8, respectively.

A branch portion 7 is connected to the proximal end of the outer pipe 2. The branch portion 7 is formed separately from the outer pipe 2 and is connected to the outer pipe 2 by means such as heat fusion or adhesion. The branch portion 7 has a primary passage 74 in which a pressure fluid conduction path 20 in the outer pipe 2 and a primary port 71 for introducing and deriving the pressure fluid into the balloon portion 4 are formed, and a wire passage in the inner pipe 3. A secondary passage 75 is formed in which a secondary port 72 communicating with 30 is formed.

The primary port 71 is connected to a pump device (not shown), and the pressure fluid is introduced and led out into the balloon portion 4 by this pump device. The primary passage 74 extends linearly inside the branch portion 7 and is connected straight to the pressure fluid conduction path 20. Therefore, inside the pressure fluid conduction path 20, the flow path resistance of the pressure fluid introduced and derived via the primary port 71 is reduced, and it becomes possible to enhance the responsiveness of expansion and contraction of the balloon portion 4. There is. The pressure fluid is not particularly limited, but helium gas having a small viscosity and a small mass or the like is used so that the balloon portion 4 quickly expands and contracts according to the drive of the pump device.

In addition to the primary port 71 and the secondary port 72, a tertiary port 73 is formed in the branch portion 7. A tertiary passage 76 for inserting the optical fiber 9 communicates with the tertiary port 73, and the proximal end side of the optical fiber 9 is drawn out from the tertiary port 73. The optical fiber 9 drawn out from the tertiary port 73 is adhesively fixed to the inside of the tertiary passage 76 close to the outlet of the tertiary port 73. The outlet of the optical fiber 9 at the tertiary port 73 is designed so that the fluid inside the primary passage 74 and the secondary passage 75 does not leak to the outside.

An optical connector 10 is connected to the proximal end of the optical fiber 9. A pressure sensor 8 for measuring blood pressure is connected to the distal end of the optical fiber 9, which will be described in detail later. A blood pressure measuring device (not shown) is connected to the optical connector 10. Based on the fluctuation of blood pressure measured by this blood pressure measuring device, the pump device is controlled according to the pulsation of the heart, and the balloon portion 4 is expanded and contracted in a short cycle of 0.4 to 1 second.

The inner peripheral surface of the outer pipe 2 and the outer peripheral surface of the inner pipe 3 are fixed by an adhesive. By fixing the outer pipe 2 and the inner pipe 3 in this way, the flow path resistance of the pressure fluid conduction path 20 in the outer pipe 2 is lowered, and the responsiveness of the balloon portion 4 is improved. The adhesive used for fixing is not particularly limited, and an adhesive such as a cyanoacrylate adhesive or an epoxy adhesive can be used, and it is particularly preferable to use a cyanoacrylate adhesive.

In the sensor-mounted catheter 1 of the present embodiment, the outer diameter of the inner tube 3 is not particularly limited, but is preferably 0.5 to 1.5 mm, preferably 30 to 60% of the inner diameter of the outer tube 2. In the present embodiment, the outer diameter of the inner pipe 3 is substantially the same along the axial direction. The inner tube 3 is composed of, for example, a synthetic resin tube such as polyurethane, polyvinyl chloride, polyethylene, polyamide, polyetheretherketone (PEEK), a nickel titanium alloy thin tube, a stainless steel thin tube, or the like. When the inner tube 3 is made of a synthetic resin tube, a stainless steel wire or the like may be embedded.

The outer tube 2 is not particularly limited, but may be made of a synthetic resin such as polyurethane, polyvinyl chloride, polyethylene terephthalate, or polyamide, and a stainless steel wire or the like may be embedded therein. The inner diameter and the wall thickness of the outer tube 2 are not particularly limited, but the inner diameter is preferably 1.5 to 4.0 mm, and the wall thickness is preferably 0.05 to 0.4 mm. The length of the outer tube 2 is preferably 300 to 800 mm.

FIG. 2 is a perspective view of the tip 5 of the tip 5 of the sensor-mounted catheter 1 shown in FIG.

As shown in FIG. 2, the tip tip 5 is roughly classified into a body portion 51 and a tip portion 52. The body portion 51 and the tip portion 52 are integrated, and a step portion 57 is formed at the boundary between the body portion 51 and the tip portion 52. The tip portion 52 located on the distal side of the step portion 57 has a larger outer diameter than the body portion 51 located on the proximal side of the step portion 57. The height of the step portion 57 is set to be about the same as the dimension corresponding to the thickness of the distal end portion 40a of the balloon portion 4 when fixed to the outer peripheral surface of the body portion 51, for example.

The body portion 51 has a substantially columnar outer shape, and constitutes most of the tip tip 5. The length of the body portion 51 along the axial direction is longer than the length of the tip portion 52 along the axial direction. The tip 52 is located distal to the body 51 and projects distally along its axial direction from the distal end of the body 51.

A plurality of curable resin filling holes 511 to 513 are opened on the outer peripheral surface of the body portion 51. A side insertion hole 54 is opened on the outer peripheral surface on the side of the tip portion 52. The opening of the side insertion hole 54 and its vicinity are covered with the resin film 11 on the outer peripheral surface side of the tip tip 5. Further, a wire insertion hole 50 and a distal end insertion hole 55 are opened at the distal end (tip) of the tip portion 52.

Hereinafter, the structure of the tip tip 5 will be described in detail with reference to FIG. FIG. 3 is a schematic cross-sectional view of the tip 5 shown in FIG. In the finally manufactured sensor-mounted catheter 1 in a usable state, for example, as shown in FIG. 8, the curable resin 14 and the pressure transmitting substance 12 are filled in the tip 5 and the lateral insertion hole 54 is formed. The opening is covered with the resin film 11, and the distal end 40a of the balloon portion 4 is fixed to the outer peripheral surface of the body portion 51. In FIG. 3, the balloon portion 4, the pressure transmitter 12, and the curable resin are fixed. 14 is not shown. It can be said that FIG. 3 illustrates the state of the tip 5 in the initial step of the method for manufacturing the sensor-mounted catheter 1 described later.

As shown in FIG. 3, the body portion 51 is formed with an inner pipe insertion hole 53 into which the inner pipe 3 is inserted. The inner tube insertion hole 53 extends from the proximal end of the body portion 51 toward the distal side, and the distal end of the inner tube insertion hole 53 is connected to the proximal end of the wire insertion hole 50. The wire insertion hole 50 is arranged so as to straddle the body portion 51 and the tip portion 52, and is opened at the distal end of the tip portion 52. The inner tube insertion hole 53 and the wire insertion hole 50 are arranged so as to communicate with each other coaxially, and the inner tube insertion hole 53 is slightly larger than the diameter of the wire insertion hole 50 (corresponding to the wall thickness of the inner tube 3). It has a diameter (larger by the size to be used). The position where the distal end of the inner tube insertion hole 53 and the proximal end of the wire insertion hole 50 are connected is not particularly limited. The distal end of the inner tube insertion hole 53 and the proximal end of the wire insertion hole 50 may be connected near the boundary between the body portion 51 and the tip portion 52, and the inner tube insertion hole 53 may be connected to the body portion 51 and the tip portion. It may be arranged so as to straddle the 52. Further, although detailed illustration is omitted, when the inner tube 3 is inserted into the inner tube insertion hole 53, the distal end of the wire passage 30 of the inner tube 3 is connected to the proximal end of the wire insertion hole 50. ..

A through hole 56 is formed straddling the body portion 51 and the tip portion 52. The through hole 56 extends along the axial direction of the tip tip 5. The through hole 56 is formed so that one end is opened at the proximal end of the tip tip 5 and the other end is connected to the proximal end of the distal end insertion hole 55. A proximal side opening 56a is formed at the proximal end of the through hole 56, so that the pressure sensor 8 and the optical fiber 9 can be inserted into the through hole 56 from the proximal side opening 56a. There is. Therefore, the outer diameter of the pressure sensor 8 generally used in the present technology is 0.1 to 0.5 mm, but the inner diameter of the through hole 56 is set larger than this. Further, the distal end of the through hole 56 is smoothly connected to the proximal end of the distal end insertion hole 55 (the proximal end of the tapered portion 55b), and the through hole 56 is the distal end insertion hole 55. It communicates with the outside of the tip 5 through the opening 55a.

The distal end insertion hole 55 is formed so that one end is connected to the distal end of the through hole 56 and the other end opens at the distal end of the tip tip 5. The distal end insertion hole 55 extends in a direction consistent with the axial direction of the through hole 56. The shape of the opening 55a of the distal end insertion hole 55 is not particularly limited, and may be, for example, a substantially rectangular shape or a substantially circular shape.

The distal end insertion hole 55 has a tapered portion 55b formed in a tapered shape so as to taper toward the distal side. The inner diameter of the proximal end of the tapered portion 55b is equal to the inner diameter of the distal end of the through hole 56, so that the proximal end of the tapered portion 55b and the distal end of the through hole 56 are smoothly connected. Further, the tapered portion 55b is formed so that the inner diameter thereof gradually decreases toward the distal side, and the diameter of the opening 55a of the distal end insertion hole 55 that opens at the distal end of the tip tip 5 is large. , It is formed so as to be smaller than the outer diameter dimension (maximum width) of the pressure sensor 8. That is, the tapered portion 55b formed tapered toward the distal side restricts the pressure sensor 8 in the through hole 56 from advancing toward the distal side. This makes it possible to prevent the pressure sensor 8 from passing through the distal end insertion hole 55 and flowing out from the opening 55a of the distal end insertion hole 55.

The outer diameter of the pressure sensor 8 generally used in the present technology is 0.1 to 0.5 mm, and the diameter of the opening 55a of the distal end insertion hole 55 is the diameter of the pressure sensor 8 to be used. It is set smaller than this based on the outer diameter dimension. The opening 55a of the distal end insertion hole 55 is set small enough to prevent the pressure sensor 8 from passing through, but is not blocked. As will be described later, the pressure transmission filled in the sensor accommodation space 70 is not closed. The substance 12 is allowed to come into direct contact with the outside through the opening 55a of the distal end insertion hole 55 (see FIG. 8).

The side insertion hole 54 is formed so that one end is connected to the through hole 56 and the other end is opened on the outer peripheral surface of the tip portion 52 of the tip tip 5. The lateral insertion hole 54 extends along the radial direction of the cross section of the tip 5 and is opened on the outer peripheral surface (lateral outer peripheral surface of the tip 52) located on the proximal side of the tip 52. There is. Further, the extending direction of the side insertion hole 54 is substantially orthogonal to the axial direction of the through hole 56, and the side insertion hole 54 communicates with the through hole 56 from the side of the through hole 56. As will be described later, the side insertion hole 54 is used as an injection hole for injecting the pressure transmitter 12. The opening 54a of the side insertion hole 54 has a diameter into which a syringe for injecting the pressure transmitter 12 can be inserted, and the diameter is, for example, 0.1 to 0.5 mm.

The curable resin filling holes 511 to 513 are formed so that one end is connected to the through hole 56 and the other end is opened on the outer peripheral surface of the body portion 51 of the tip tip 5. In this embodiment, three curable resin filling holes 511 to 513 are provided. The openings 511a to 513a of the curable resin filling holes 511 to 513 are formed so as to be arranged substantially in a straight line along the axial direction on the outer peripheral surface of the body portion 51.

The curable resin filling holes 511 to 513 extend along the cross-sectional radial direction of the tip tip 5 and are opened on the outer peripheral surface of the body portion 51 (the outer peripheral surface on the side of the body portion 51). Further, the extending direction of the curable resin filling holes 511 to 513 is substantially orthogonal to the axial direction of the through hole 56, and the curable resin filling holes 511 to 513 communicate with the through hole 56 from the side of the through hole 56. ing. The openings 511a to 513a of the curable resin filling holes 511 to 513 have, for example, a substantially circular shape. As will be described later, the curable resin filling holes 511 to 513 are used as injection holes for injecting the curable resin 14. The openings 511a to 513a of the curable resin filling holes 511 to 513 have a diameter into which a syringe 13 for injecting the curable resin 14 can be inserted, and the diameter is, for example, 0.1 to 0.5 mm.

In the present embodiment, the curable resin filling hole 511 is connected to the proximal end side of the through hole 56, and the curable resin filling hole 513 is connected to the distal end side of the through hole 56 and is cured. The sex resin filling hole 512 is connected to a through hole 56 between the curable resin filling hole 511 and the curable resin filling hole 512. The curable resin filling holes 511 to 513 are used for injecting the curable resin 14 into the through hole 56 of the body portion 51 for the purpose of fixing the optical fiber 9 in the through hole 56, as will be described later. The positions and numbers of the curable resin filling holes 511 to 513 are not particularly limited as long as they achieve this object.

The pressure sensor 8 is a sensor that measures pressure by utilizing the path difference of light transmitted through the optical fiber 9. The pressure sensor 8 is attached to the distal end of the optical fiber 9, is inserted into the through hole 56 together with the optical fiber 9, and is arranged in the sensor accommodating space 70 filled with the pressure transmitting material 12, as will be described later. Will be done. External pressure (blood pressure) is transmitted to the pressure sensor 8 through the opening 55a of the distal end insertion hole 55 via a pressure transmitter. The pressure sensor 8 detects this pressure and transmits an optical signal including the detection result to the optical connector 10 through the optical fiber 9.

The pressure sensor 8 generally used in the present technical field has, for example, a substantially cylindrical shape, the outer diameter of which is 0.1 to 0.5 mm, and the size of the shaft method is about 1 to 10 mm. As the pressure sensor 8, those described in JP-A-2008-524606, JP-A-2000-35369 and the like can be used.

Further, a substantially cylindrical member 60 is arranged on the proximal side separated from the pressure sensor 8 by a predetermined distance. The substantially cylindrical member 60 is, for example, a member made of stainless steel, the outer diameter thereof is smaller than the inner diameter of the through hole 56, and the member can be inserted into the through hole 56. An optical fiber 9 is inserted into the cavity of the substantially cylindrical member 60, and the substantially cylindrical member 60 and the optical fiber 9 are fixed with an adhesive or the like. Therefore, the distance between the pressure sensor 8 and the substantially cylindrical member 60 is always maintained at a predetermined distance regardless of the advancement and retreat of the optical fiber 9 in the axial direction.

The predetermined distance between the pressure sensor 8 and the substantially cylindrical member 60 is, for example, a part of the substantially cylindrical member 60 (for example, the distal end surface 60a of the substantially cylindrical member 60) when the pressure sensor 8 is properly positioned. It is set so as to be arranged below the side insertion hole 54 (inward in the radial direction of the side insertion hole 54). For example, as shown in FIG. 3, the distance between the distal end of the pressure sensor 8 and the inner peripheral surface on the distal end side of the lateral insertion hole 54 when the pressure sensor 8 is properly positioned is L1 and is lateral. Assuming that the inner diameter of the insertion hole 54 is L2, the distance L between the distal end of the pressure sensor 8 and the distal end surface 60a of the substantially cylindrical member 60 is set to be in the range of L1 ≦ L ≦ L1 + L2. By determining the distance between the pressure sensor 8 and the substantially cylindrical member 60 in this way, the distal end surface 60a of the substantially cylindrical member 60 can be visually recognized from the side insertion hole 54 when the pressure sensor 8 is properly positioned. It is placed in a suitable position. That is, by using the substantially cylindrical member 60 (here, the distal end surface 60a of the substantially cylindrical member 60) as a marker that can be seen from the side insertion hole 54, the position of the pressure sensor 8 in the axial direction is appropriately determined. be able to.

Next, an example of a method for manufacturing the sensor-mounted catheter 1 according to the embodiment of the present invention will be described with reference to FIGS. 3 to 8.

First, the tip 5 and the optical fiber 9 to which the pressure sensor 8 is attached to the distal end are prepared. The method for forming the tip 5 is not particularly limited and will not be described in detail, but it is manufactured by, for example, an injection molding method using a synthetic resin material such as polyurethane, polyvinyl chloride, polyethylene terephthalate, or polyamide. be able to.

Then, the pressure sensor 8 is inserted into the through hole 56 through the proximal opening 56a, and light is applied until the pressure sensor 8 is placed near the distal end of the through hole 56 (in front of the distal end insertion hole 55). Push the fiber 9 toward the distal side. At this time, while looking inside the side insertion hole 54, the optical fiber 9 is pushed into a position where the distal end surface 60a of the substantially cylindrical member 60 can be visually recognized to position the pressure sensor 8. As a result, as shown in FIG. 3, the pressure sensor 8 is arranged at an appropriate position near the distal end of the through hole 56, and the distal end of the optical fiber 9 is arranged in the through hole 56.

Next, the curable resin 14 is injected into the through hole 56 and fixed in the through hole 56 at the distal end of the optical fiber 9. The curable resin 14 is not particularly limited, but a resin such as an adhesive that has fluidity at the time of filling and is cured after filling is preferably used. Specific examples of the resin used as the curable resin 14 include a moisture-curable adhesive such as a cyanoacrylate-based adhesive, a heat-curable adhesive such as an epoxy-based one-component adhesive, and an epoxy-based two-component adhesive. Two-component mixed curing type adhesives such as, etc. can be mentioned.

For example, as shown in FIG. 4, first, the syringe 13 filled with the curable resin 14 is inserted into the curable resin filling hole (hereinafter, the second filling hole) 512, and the curable resin 14 is inserted from the syringe 13. Inject. The curable resin 14 injected through the second filling hole 512 flows into the through hole 56 and flows out from there toward the proximal side and the distal side of the through hole 56. At this time, while looking inside the curable resin filling hole (hereinafter, the third filling hole) 513, the curable resin 14 is injected through the second filling hole 512, and the curable resin flows toward the distal side of the through hole 56. The curable resin 14 is injected until 14 can be seen from the third filling hole 513.

When the curable resin 14 injected through the second filling hole 512 reaches a position visible from the third filling hole 513, the curable resin 14 is placed in the area between the second filling hole 512 and the third filling hole 513. The through hole 56 is fully filled without any gap. Therefore, by visually recognizing the curable resin 14 that has flowed below the third filling hole 513, the curable resin 14 in the through hole 56 in the area between the second filling hole 512 and the third filling hole 513 is filled. You can grasp the condition. The curable resin 14 injected through the second filling hole 512 also flows in the through hole 56 toward the proximal side (below the first filling hole 511). Further, since the curable resin 14 is injected through the second filling hole 512, the curable resin 14 is filled up to the opening 512a of the second filling hole 512 (see FIG. 4).

Next, as shown in FIG. 5, the syringe 13 filled with the curable resin 14 is inserted into the curable resin filling hole (hereinafter referred to as the first filling hole) 511, and the curable resin 14 is removed from the syringe 13. inject. By injecting the curable resin 14 through the first filling hole 511, the curing resin 14 is injected into the through hole 56 in the area between the first filling hole 511 and the second filling hole 512 and in the area proximal to the first filling hole. The holes 56 are fully filled with the curable resin 14 without any gaps. Further, since the curable resin 14 is injected through the first filling hole 511, the curable resin 14 is filled up to the opening 511a of the first filling hole 511 (see FIG. 5).

Further, as shown in FIG. 6, a syringe 13 filled with the curable resin 14 is inserted into the third filling hole 513, and the curable resin 14 is injected from the syringe 13. The curable resin 14 injected through the third filling hole 513 flows into the through hole 56 and flows out from there toward the distal side of the through hole 56. The curable resin 14 is already filled in the through hole 56 proximal to the bottom of the third filling hole 513.

A substantially cylindrical member 60 is arranged in the through hole 56 in the area between the third filling hole 513 and the side insertion hole 54 so that its distal end surface 60a is located below the side insertion hole 54. ing. The curable resin 14 injected through the third filling hole 513 passes through the outside of the outer peripheral surface of the substantially cylindrical member 60 (between the outer peripheral surface of the substantially cylindrical member 60 and the inner peripheral surface of the through hole 56) and passes through the hole 56. It flows inward toward the distal side. At this time, the curable resin 14 is injected through the third filling hole 513 while looking inside the side insertion hole 54, and the curable resin 14 flowing toward the distal side of the through hole 56 can be visually recognized from the side insertion hole 54. The curable resin 14 is injected until.

When the curable resin 14 injected through the third filling hole 513 reaches a position visible from the side insertion hole 54, the curable resin 14 is placed in the area between the third filling hole 513 and the side insertion hole 54. The through hole 56 is fully filled without any gap. Therefore, by visually recognizing the curable resin 14 that has flowed below the side insertion hole 54, the curable resin 14 in the through hole 56 in the area between the third filling hole 513 and the side insertion hole 54 is filled. You can grasp the condition. Further, since the curable resin 14 is injected through the third filling hole 513, the curable resin 14 is filled up to the opening 513a of the third filling hole 513.

When the curable resin 14 that has flowed under the side insertion hole 54 can be visually recognized through the side insertion hole 54, the injection of the curable resin 14 that has been performed through the third filling hole 513 is completed. When the injection of the curable resin 14 is completed, the curable resin 14 does not flow into the through hole 56 on the distal side from below the side insertion hole 54, and the curable resin 14 does not adhere to the pressure sensor 8. As described above, the filling operation of the curable resin 14 into the through hole 56 is completed. After that, the curable resin 14 is cured and fixed in the through hole 56 at the distal end of the optical fiber 9, so that the optical fiber 9 to which the pressure sensor 8 is attached at the distal end is through the hole of the tip tip 5. It can be fixed within 56.

The surface of the substantially cylindrical member 60 arranged in the through hole 56 secures a fixing surface to which the curable resin 14 is fixed, and the fixing strength for fixing the optical fiber 9 in the through hole 56 can be increased. Will be. That is, the substantially cylindrical member 60 not only serves as a positioning marker for arranging the pressure sensor 8 at an appropriate position as described above, but also enhances the fixing strength for fixing the optical fiber 9 in the through hole 56. It has a role as a member for the purpose.

Subsequently, after the curable resin 14 is cured, the pressure transmitter 12 is filled around the pressure sensor 8. As the pressure transmitting substance 12, for example, a gel-like substance such as silicone gel, polyacrylamide gel, or polyethylene oxide gel, an oil-like substance such as silicone oil, or the like can be used.

By the above-mentioned injection operation of the curable resin 14, the curable resin 14 is filled in the through hole 56 on the proximal side from below the side insertion hole 54, and is in a cured state. Below the lateral insertion hole 54, the distal end 14a of the cured curable resin 14 exists so as to close the proximal side of the through hole 56, and is located below the distal end 14a of the cured curable resin 14. A sensor accommodating space 70 accommodating the pressure sensor 8 is defined in the through hole 56 on the distal side. A side insertion hole 54 and a distal end insertion hole 55 communicate with the sensor accommodation space 70. That is, the sensor accommodation space 70 is a space defined distal to the distal end 14a of the cured curable resin 14, and is an opening of the side insertion hole 54 and the opening of the distal end insertion hole 55. It is open to the outside at two points of the portion 55a (see FIG. 6).

As shown in FIG. 7, the pressure transmitter 12 is filled in the sensor accommodating space 70 through the side insertion hole 54. The pressure transmitter 12 injected through the side insertion hole 54 flows into the sensor accommodating space 70 defined distal to the distal end 14a of the cured curable resin 14. At this time, the pressure transmitter 12 flows into the sensor accommodation space 70 while pushing out the air in the sensor accommodation space 70 from the distal end insertion hole 55. When the pressure transmitter 12 that has flowed into the sensor accommodation space 70 is sufficiently filled in the sensor accommodation space 70 without any gap, the pressure transmitter 12 flows out from the distal end insertion hole 55. Therefore, by confirming the outflow of the pressure transmitter 12 from the distal end insertion hole 55, it is possible to grasp the filling condition of the pressure transmitter 12 in the sensor accommodation space 70.

By injecting the pressure transmitting substance 12 through the side insertion hole 54 in this way, the air accumulated in the sensor accommodating space 70 escapes from the distal end insertion hole 55, and air bubbles (voids) enter the sensor accommodating space 70. The circumference of the pressure sensor 8 is surely filled with the pressure transmitting substance 12, and the measurement accuracy of the pressure sensor 8 can be improved.

After that, a resin film 11 is formed in and around the opening 54a of the side insertion hole 54 so as to close the opening 54a of the side insertion hole 54 used for injecting the pressure transmitter 12. For example, by dripping a liquefied resin from the outer peripheral surface side of the tip tip 5 around the opening 54a of the side insertion hole 54 and solidifying it, the opening 54a of the side insertion hole 54 is formed by the resin film 11. It is assumed that the tip 5 is covered with the outer peripheral surface side. This makes it possible to prevent the pressure transmitter 12 from flowing out from the side insertion hole 54. For the resin film 11, a material such as urethane resin, silicone resin, or polyamide elastomer can be used from the viewpoint of sufficiently ensuring compatibility with the living body.

Regarding the opening 55a of the distal end insertion hole 55, the pressure transmitter 12 filled in the sensor accommodating space 70 is externally passed through the opening 55a of the distal end insertion hole 55 without being blocked by the resin film 11 or the like. To be in direct contact with. Although the distal end insertion hole 55 is open to the outside, the opening 55a of the distal end insertion hole 55 is formed to be small, so that the outside of the pressure transmitter 12 filled in the sensor accommodation space 70 (patient's). The amount of outflow to the body) can be reduced. Further, since the distal end insertion hole 55 has an opening 55a having a diameter smaller than the outer diameter of the pressure sensor 8, the pressure sensor 8 can be moved from the distal end insertion hole 55, for example, when the optical fiber 9 is broken. Even when the pressure sensor 8 is about to flow out, the pressure sensor 8 cannot pass through the distal end insertion hole 55 to prevent the pressure sensor 8 from flowing out to the outside of the tip tip 5 (inside the patient's body). Can be done.

Further, for each of the first to third filling holes 511 to 513, similarly to the opening 54a of the side insertion hole 54, the openings 511a to 513a of the first to third filling holes 511 to 513 are closed. The resin film 11 is formed. Then, the distal side of the inner tube 3 is inserted into the inner tube insertion hole 53 of the body portion 51 to be connected and fixed, and the distal end portion 40a of the balloon portion 4 is proximal to the body portion 51 by heat fusion or adhesion or the like. Fix to the outer peripheral surface on the side. On the outer peripheral surface on the proximal side of the body portion 51 to which the distal end portion 40a of the balloon portion 4 is fixed, openings 511a to 513a of the first to third filling holes 511 to 513 are present. When the curable resin 14 filled in the first to third filling holes 511 to 513 is exposed, sufficient fixing strength may not be secured, but the first to third filling holes 511 to 513 may not be secured. By covering the openings 511a to 513a of the above with the resin film 11, the distal end portion 40a of the balloon portion 4 can be fixed with a higher fixing strength than when the curable resin 14 is exposed. As shown in FIG. 8, the sensor-mounted catheter 1 is manufactured by the above manufacturing method.

Hereinafter, the operation according to the present invention will be described.

The sensor-mounted catheter 1 according to the present invention includes a catheter tube (inner tube) 3, a pressure sensor 8 capable of measuring pressure using light, an optical fiber 9 connected to the pressure sensor 8, and a catheter tube 3. It has a tip 5 provided at the distal end of the surface, through which an optical fiber 9 is inserted and a through hole 56 is formed in which a sensor accommodating space 70 accommodating a pressure sensor 8 is defined. The tip tip 5 is formed with a lateral insertion hole 54 and a distal end insertion hole 55. The side insertion hole 54 is used as an injection hole for the pressure transmitter 12 into the sensor accommodation space 70, communicates with the sensor accommodation space 70, and opens on the outer peripheral surface of the tip tip 5. The distal end insertion hole 55 is used as a pressure collection hole for measuring external pressure, communicates with the sensor accommodating space 70, and opens at the distal end of the tip tip 5, and has an outer diameter dimension of the pressure sensor 8. It has an opening 55a with a smaller diameter. The opening 54a of the side insertion hole 54 is covered with the resin film 11 on the outer peripheral surface side of the tip tip 5.

According to this configuration, the side insertion hole 54 and the distal end insertion hole 55 communicate with the sensor accommodating space 70 filled with the pressure transmitting material 12, and the pressure transmitting material 12 is injected through the side insertion hole 54. At that time, the air in the sensor accommodating space 70 escapes from the distal end insertion hole 55, no air bubbles (voids) remain in the sensor accommodating space 70, and the pressure sensor 8 is surely covered with the pressure transmitting material 12 to make a pressure sensor. The measurement accuracy of 8 can be improved.

Further, the lateral insertion hole 54 used for injecting the pressure transmitting substance 12 is covered with the resin film 11 to close the side insertion hole 54, while the distal end insertion hole 55 used as a pressure collection hole for measuring the external pressure (blood pressure). Since the configuration can be configured to be open to the outside without blocking the pressure sensor 8, the pressure sensor 8 can sufficiently and reliably detect the external pressure (blood pressure), and the measurement accuracy of the pressure sensor 8 can be improved. Will be.

Further, the distal end insertion hole 55 has an opening 55a having a diameter smaller than the outer diameter of the pressure sensor 8. For example, even if the pressure sensor 8 is about to flow out of the distal end insertion hole 55 due to a break in the optical fiber 9, the pressure sensor 8 cannot pass through the distal end insertion hole 55, which means that the pressure sensor 8 cannot pass through the distal end insertion hole 55. This makes it possible to prevent the pressure sensor 8 from flowing out to the outside of the tip tip 5 (inside the patient's body). Further, since the opening 55a of the distal end insertion hole 55 is formed to be small, the amount of the pressure transmitter 12 filled in the sensor accommodation space 70 to the outside (inside the patient's body) can be reduced. ..

Further, in the sensor-mounted catheter 1 according to the present invention, the distal end insertion hole 55 may be formed in a tapered shape in which the distal end insertion hole 55 narrows from the sensor accommodation space 70 toward the opening 55a.

According to this configuration, the distal end insertion hole 55 can be formed so as to have an opening 55a having a diameter smaller than the outer diameter of the pressure sensor 8, and the pressure sensor 8 is outside the tip 5 (inside the patient). ) Can be reliably prevented from leaking to).

Further, the sensor-mounted catheter 1 according to the present invention is provided with a marker visible from the side insertion hole 54 when the pressure sensor 8 is arranged at an appropriate position in the sensor accommodation space 70 on the optical fiber 9. You may be.

According to this configuration, when the pressure sensor 8 is arranged in the sensor accommodation space 70, the position of the pressure sensor 8 can be grasped by checking the marker visible from the side insertion hole 54, and the pressure sensor 8 can be operated. It will be possible to place it in an appropriate position.

Further, the sensor-mounted catheter 1 according to the present invention may be a substantially cylindrical member 60 in which the marker is fixed to the optical fiber 9 with the optical fiber 9 inserted.

According to this configuration, the position of the pressure sensor 8 is grasped and the pressure sensor is appropriately used by visually recognizing the substantially cylindrical member 60 that advances and retreats together with the optical fiber 9 and the pressure sensor 8 in the through hole 56 from the side insertion hole 54. It will be possible to place it in any position. Further, a fixing surface to which the curable resin 14 such as an adhesive is fixed is secured by the surface of the substantially cylindrical member 60, and the fixing strength for fixing the optical fiber 9 in the through hole 56 can be increased.

Further, the sensor-mounted catheter 1 according to the present invention is used in the tip 5 as an injection hole for the curable resin 14 into the through hole 56, and is provided in the through hole 56 on the proximal end side of the sensor accommodation space 70. Curable resin filling holes 511 to 513 may be formed so as to communicate with each other and open on the outer peripheral surface of the tip tip 5.

According to this configuration, the curable resin 14 can be directly filled in the through holes 56 through the curable resin filling holes 511 to 513 without adhering the curable resin 14 to the pressure sensor 8. As a result, the optical fiber 9 can be fixed in the through hole 56.

Further, in the sensor-mounted catheter 1 according to the present invention, the openings 511a to 513a of the curable resin filling holes 511 to 513 may be covered with the resin film 11 on the outer peripheral surface side of the tip tip 5.

According to this configuration, the adhesiveness or heat fusion property can be improved when another member such as the distal end portion 40a of the balloon portion 4 is joined to the outer peripheral surface of the tip tip 5.

The embodiments described above are described for facilitating the understanding of the present invention, not for limiting the present invention. Therefore, each element disclosed in the above-described embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

1 Sensor-mounted catheter 2 Outer tube 3 Inner tube (catheter tube)
4 Balloon part 5 Tip tip 6 Contrast marker 7 Branch part 8 Pressure sensor 9 Optical fiber 10 Optical connector 11 Resin film 12 Pressure transmitter 13 Syringe 14 Curable resin 14a Distal end of curable resin 20 Pressure fluid conduction path 30 Wire passage 40a Distal end of balloon part 40b Proximal end of balloon part 50 Wire insertion hole 51 Body part 52 Tip part 53 Inner tube insertion hole 54 Side insertion hole 54a Side insertion hole opening 55 Distal side insertion hole 55a Distal side insertion hole opening 56 Through hole 56a Proximal side opening of through hole 57 Stepped part 60 Approximately cylindrical member 60a Approximately cylindrical member distal end face 70 Sensor accommodation space 71 Primary port 72 Secondary port 73 Tertiary Port 74 Primary passage 75 Secondary passage 76 Tertiary passage 511 Curable resin filling hole (first filling hole)
511a Opening of curable resin filling hole (first filling hole) 512 Curable resin filling hole (second filling hole)
512a Opening of curable resin filling hole (second filling hole) 513 Curable resin filling hole (third filling hole)
513a Opening of curable resin filling hole (third filling hole)

Claims

Catheter tube and
A pressure sensor that can measure pressure using light,
The optical fiber connected to the pressure sensor and
It has a tip tip provided at the distal end of the catheter tube and formed with a through hole through which the optical fiber is inserted and a sensor accommodation space for accommodating the pressure sensor is defined.
The tip is used as an injection hole for a pressure transmitting substance into the sensor accommodating space, and has a side insertion hole that communicates with the sensor accommodating space and opens on the outer peripheral surface of the tip tip, and external pressure. A distal end insertion hole that is used as a pressure collection hole for measurement, communicates with the sensor accommodation space, opens at the distal end of the tip, and has an opening with a diameter smaller than the size of the pressure sensor. Is formed,
A sensor-mounted catheter characterized in that the opening of the lateral insertion hole is covered with a resin film on the outer peripheral surface side of the tip.
The sensor-mounted catheter according to claim 1, wherein the distal end insertion hole is formed in a tapered shape that narrows from the sensor accommodation space toward the opening.
According to claim 1 or 2, the optical fiber is provided with a marker that can be visually recognized from the side insertion hole when the pressure sensor is arranged at an appropriate position in the sensor accommodation space. The sensor-mounted catheter described.
The sensor-mounted catheter according to claim 3, wherein the marker is a substantially cylindrical member fixed to the optical fiber with the optical fiber inserted.
The tip is used as a hole for injecting a curable resin into the hole, and is curable so as to communicate with the hole on the proximal end side of the sensor accommodation space and open on the outer peripheral surface of the tip. The sensor-mounted catheter according to any one of claims 1 to 4, wherein a resin-filled hole is formed.
The sensor-mounted catheter according to claim 5, wherein the opening of the curable resin filling hole is covered with a resin film on the outer peripheral surface side of the tip.