JP6381138B2 - catheter - Google Patents

Description

  The present invention relates to a medical catheter.

  2. Description of the Related Art Conventionally, in order to make it possible to visually recognize the tip position of a catheter during a procedure, a device having a radiopaque marker at the tip portion of the catheter is known.

  For example, Patent Document 1 discloses an elongate tubular body 10 composed of a polytetrafluoroethylene core 16 and a polyurethane jacket 18 covering the polytetrafluoroethylene core 16, and a distal end of the tubular body 10. There is disclosed a catheter provided with a radio-opaque noble metal marker band 14 at a portion where the tubular body 10 and the soft tip 12 are connected to each other (see page 5). (See upper right column and Fig. 1 etc.).

  Patent Document 2 includes a resin inner layer tube, a reinforcing material layer wound around the outer periphery of the inner layer tube, and an outer layer tube covering the inner layer tube and the reinforcing material layer, and is in contact with the reinforcing material layer. A medical catheter tube in which a radiopaque marker is disposed is disclosed (see FIG. 20 and the like).

JP-A-64-68276 JP 2006-34347 A

  However, the conventional catheter as described above has a problem that the rigidity of the part where the radiopaque marker is arranged becomes extremely higher than that of the other part.

  More specifically, the distal end portion of the conventional catheter is made of a highly flexible resin in order to facilitate insertion into the body. However, when a radiopaque marker composed of a metal material such as platinum is disposed at the distal end of the catheter, the rigidity of the portion becomes high, and the radiopaque marker is disposed with the portion where the radiopaque marker is disposed. A rigidity gap will be generated in the boundary region with the non-exposed portion. Therefore, for example, when a technician operates a conventional catheter and repeatedly curves the catheter in the body, stress is applied to the boundary region between the portion where the radiopaque marker is placed and the portion where the radiopaque marker is not placed. There is a problem that the catheter is easily concentrated in the boundary region due to excessive concentration.

Therefore, the present invention provides a catheter with a radiopaque marker that prevents excessive stress concentration and ensures flexibility of the catheter tip even when the catheter is inserted into a blood vessel and bent. An object of the present invention is to provide a catheter capable of preventing breakage.

  To achieve the above object, according to a first aspect of the present invention, there is provided a catheter comprising a tubular body and a radiopaque marker disposed on the tubular body, wherein the radiopaque marker is the tubular body. The catheter is characterized by being fixed so as to provide a gap between the radiopaque marker and the tubular body in the radiation direction of the body.

  According to this configuration, in the catheter provided with the tubular body and the radiopaque marker disposed on the tubular body, the radiopaque marker includes the radiopaque marker and the tubular body in the radial direction of the tubular body. Since it is fixed so as to provide a gap between them, even when the catheter is inserted into a blood vessel and curved, it prevents excessive stress concentration and ensures the flexibility of the catheter tip and breaks Can be prevented.

According to a second aspect of the present invention, there is provided the catheter according to the first aspect of the present invention, wherein the gap is provided on both sides in the radial direction with respect to the radiopaque marker. .

  According to such a configuration, in addition to the effect of the first aspect of the present invention, since the gap is provided on both sides in the radial direction with respect to the radiopaque marker, the catheter is inserted into the blood vessel and curved. Even in this case, excessive stress concentration can be further prevented, the flexibility of the catheter tip can be secured, and breakage can be further prevented.

Moreover, the 3rd aspect of this invention is equipped with the reinforcement member arrange | positioned along the major axis direction of the said tubular body in the inside of the said tubular body in the 1st aspect or 2nd aspect of this invention. The radiopaque marker is a catheter fixed to the tip of the reinforcing member.

  According to such a configuration, in addition to the effects of the first aspect or the second aspect of the present invention, the tubular body includes the reinforcing member disposed along the longitudinal direction of the tubular body, and is radiopaque. Since the marker is fixed to the tip of the reinforcing member, the radiopaque marker can be prevented from being displaced and excessive stress concentration can be reliably prevented, and breakage can be reliably prevented.

Furthermore, a fourth aspect of the present invention is characterized in that, in the third aspect of the present invention, the gap is formed to extend to a tip of the reinforcing member to which the radiopaque marker is fixed. It is a catheter.

  According to such a configuration, in addition to the effect of the third aspect of the present invention, the gap is formed so as to extend to the tip of the reinforcing member to which the radiopaque marker is fixed, so that the catheter is inserted into the blood vessel. Even when it is bent, excessive stress concentration can be further prevented, the flexibility of the catheter tip can be secured, and breakage can be further prevented.

  The catheter of the present invention can prevent excessive stress concentration, ensure flexibility of the distal end portion of the catheter, and prevent breakage even when the catheter is inserted into a blood vessel and bent.

It is a top view of the catheter of a 1st embodiment of the present invention. It is a partial expanded sectional view of the catheter of a 1st embodiment. It is a partial expanded sectional view which shows the modification of the catheter of 1st Embodiment. It is a partial expanded sectional view of the catheter of 2nd Embodiment. It is a partial expanded sectional view of the catheter of 3rd Embodiment. It is a partial expanded sectional view of the catheter of 4th Embodiment.

[First Embodiment]
Hereinafter, a catheter according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of the catheter of the first embodiment of the present invention, and FIG. 2 is a partially enlarged sectional view of the catheter of the first embodiment.

As shown in FIG. 1, the catheter 1 includes an operation unit 10 operated by an operator and a catheter tube (corresponding to a “tubular body” of the present invention) 20 connected to the distal end of the operation unit 10. The catheter tube 20 includes a catheter body 21 that extends from the operation section 10 and a distal tip 22 that is located on the distal end side of the catheter body 21. The vicinity of the distal end of the catheter main body 21 and the vicinity of the distal end of the distal tip 22 each have a tapered shape whose outer diameter decreases toward the distal end.

  Further, as shown in FIG. 2, the catheter body 21 has a multilayer structure, and is composed of an inner layer 24, a braid 25, and an outer layer 26 in order from the radial inner side with respect to the central axis of the catheter body 21. It is configured.

  The inner layer 24 has a tubular shape having a lumen 23 and is disposed over the catheter body 21 and the distal tip 22. The inner layer 24 is preferably made of a fluorine-based resin such as polytetrafluoroethylene having a small sliding resistance. Further, the inner layer 24 may be partly or entirely made of a multilayer structure.

  A braid 25 is disposed on the outer periphery of the inner layer 24. The distal end of the braid 25 is disposed in the distal tip 22 and is located on the proximal side with respect to the distal end of the inner layer 24. In the present embodiment, the braid 25 in which a plurality of strands are knitted is disposed on the outer periphery of the inner layer 25, but a coil in which a single strand or a plurality of strands are wound may be disposed. The braid 25 is made of a material such as stainless steel, a superelastic alloy such as a Ni-Ti alloy, a piano wire, or a tungsten wire.

  An outer layer 26 is disposed so as to cover the outer peripheries of the inner layer 24 and the braid 25, and the distal end of the outer layer 26 constitutes the distal end of the catheter main body 21. In the outer layer 26, a reinforcing member 27 made of a coil is arranged coaxially with the outer layer 26. The reinforcing member 27 and the outer layer 26 constitute a reinforcing layer 28. Note that the distal end of the reinforcing member 27 extends to the distal end of the catheter main body 21. In this embodiment, a coil is used as the reinforcing member 27, but a braid formed by knitting a plurality of strands may be used. The reinforcing member 27 is made of a material such as stainless steel, a superelastic alloy such as a Ni—Ti alloy, a piano wire, or a tungsten wire.

  Examples of the resin material constituting the outer layer 26 include polyamide, polyamide elastomer, polyester, polyurethane, and the like. In this embodiment, polyurethane is used. Further, the outer layer 26 may be partly or wholly formed in a multilayer structure.

  The distal tip 22 has a multilayer structure, and is composed of an inner layer 24, a braid 25, and a distal outer layer 29 continuously formed from the outer layer 26 in order from the radial inner side with respect to the central axis of the distal tip 22. It is configured. As the resin material constituting the tip outer layer 29, for example, polyamide, polyamide elastomer, polyester, polyurethane, or the like can be used as in the outer layer 26. In addition, polyurethane is used for the front-end | tip outer layer 29 of this embodiment. Thus, the main part of the tip 22 is made of polyurethane, so that damage to the inner wall of the blood vessel can be prevented. In order to improve the visibility of the tip 22, it is desirable that the tip outer layer 29 contains a radiopaque tungsten powder or the like.

  In addition, a radiopaque marker 30 made of a ring-shaped platinum material is disposed in the distal tip 22, and the base end of the radiopaque marker 30 is fixed to the distal end of the reinforcing member 27 via the fusion part 30 a. Has been. Specifically, the proximal end of the radiopaque marker 30 and the distal end of the reinforcing member 27 are fused by YAG welding. In addition, although the radiopaque marker 30 used platinum in this embodiment, you may use other metal materials which are radiopaque. In this embodiment, the proximal end of the radiopaque marker 30 and the distal end of the reinforcing member 27 are fused, but may be fixed by other fixing methods such as an adhesive.

  In addition, as shown in FIG. 2, a gap 35 is provided between the inner layer 24 and the radiopaque marker 30 inside the catheter tube 20 in the radial direction, and a part of the outer peripheral surface of the radiopaque marker 30 is provided. Is exposed in the gap 35. That is, the surface on the inner layer 24 side of the outer peripheral surface of the radiopaque marker 30 is not in contact with other members.

In the catheter 1, the radiopaque marker 30 is fixed so as to provide a gap 35 between the radiopaque marker 30 and the catheter tube 20 on the inner side in the radial direction of the catheter tube 20. Even when it is inserted and curved, the gap 35 can sufficiently absorb the deformation of the inner layer 24, the distal outer layer 29 and the like in the vicinity of the radiopaque marker 30, thereby preventing excessive stress concentration. . Thereby, the softness | flexibility of the catheter 1 front-end | tip part can be ensured and the fracture | rupture of the catheter 1 can be prevented.

  Furthermore, as described above, since the radiopaque marker 30 is fused with the tip of the reinforcing member 27, the radiopaque marker 30 is prevented from being displaced, and excessive stress concentration is reliably prevented. Thus, breakage of the catheter 1 can be reliably prevented. Also in the manufacturing process of the catheter tube 20, the distal outer layer 29 can be formed in a state where the radiopaque marker 30 is fused to the distal end of the reinforcing member 27, so that the radiopaque marker 30 is positioned. Deviation is prevented, and the catheter 1 can be manufactured with high dimensional accuracy.

Furthermore, the resin material constituting the distal end outer layer 29 permeates into the gap 35 formed on the inner layer 24 side of the radiopaque marker 30 by fusing the reinforcing member 27 and the radiopaque marker 30. Therefore, the gap 35 can be easily formed.

Further, since the gap portion 35 is also formed between the fused portion 30a (the tip of the reinforcing member 27) and the inner layer 24, excessive stress is applied when the catheter 1 is inserted into the blood vessel and bent. Concentration can be further prevented, the flexibility of the distal end portion of the catheter 1 can be secured, and the breakage of the catheter 1 can be further prevented.

FIG. 3 is a partially enlarged cross-sectional view showing a modification of the catheter of the first embodiment. In FIG. 3, a leading end outer layer 29 partially penetrates into a gap 35 provided between the radiopaque marker 30 and the inner layer 24. According to such a configuration, the radiopaque marker 30 is supported from below by the distal end outer layer 29 in addition to being fused to the reinforcing member 27 via the fused portion 30a. The positional deviation of the sex marker 30 is further prevented.

  The invention having such a configuration includes a tubular body and a radiopaque marker disposed on the tubular body, and the radiopaque marker is arranged in the radial direction of the tubular body with the radiopaque marker and the tubular body. The tubular body is fixed in a state where the tubular body is inserted into an edge portion of the radiopaque marker so that a gap portion is provided between them.

[Second Embodiment]
Hereinafter, although the catheter of 2nd Embodiment is demonstrated, while the point which is common with the catheter of 1st Embodiment is simplified or abbreviate | omitted, the same code | symbol is attached | subjected in drawing.

  FIG. 4 is a partially enlarged cross-sectional view of the catheter of the second embodiment. In FIG. 4, the catheter tube 50 is different in the positional relationship between the radiopaque marker and the gap as compared with the catheter tube 20 of the first embodiment.

That is, the base end of the radiopaque marker 60 disposed on the distal tip 22 is fused to the distal end of the reinforcing member 57 constituting the reinforcing layer 58 via the fused portion 60a, but the first embodiment. The void portion 35 in the catheter tube 20 is disposed on the inner side in the radiation direction of the catheter tube 20 with respect to the radiopaque marker 30, whereas the void portion 65 of the present embodiment is a radiopaque marker. 60, the catheter tube 50 is disposed in the radiation direction outside (between the radiopaque marker 60 and the distal outer layer 59).

According to this configuration, when the catheter is inserted into the blood vessel and bent, excessive stress concentration can be prevented, the flexibility of the distal end portion of the catheter can be secured, and the catheter can be prevented from being broken. Further, since the gap portion 65 is also formed between the fused portion 60a (tip of the reinforcing member 57) and the tip outer layer 59, excessive stress is applied when the catheter is inserted into the blood vessel and bent. Concentration can be further prevented, the flexibility of the distal end of the catheter can be secured, and the catheter can be further prevented from breaking.

[Third Embodiment]
Hereinafter, the catheter of the third embodiment will be described, but the points common to the catheter of the first embodiment and the catheter of the second embodiment will be simplified or omitted, and the same reference numerals will be given in the drawings.

FIG. 5 is a partially enlarged cross-sectional view of the catheter of the third embodiment. In FIG. 5, the catheter tube 70 is different in the positional relationship between the radiopaque marker and the gap as compared with the catheter tube 20 of the first embodiment.

That is, the base end of the radiopaque marker 80 disposed on the distal tip 22 is fused to the distal end of the reinforcing member 77 constituting the reinforcing layer 78 via the fused portion 80a. The voids 85 are on both sides of the catheter tube 70 in the radiation direction with respect to the radiopaque marker 80 (between the radiopaque marker 80 and the inner layer 25 and between the radiopaque marker 80 and the distal outer layer 79). Is arranged.

According to such a configuration, when the catheter is inserted into a blood vessel and bent, excessive stress concentration can be further prevented, the flexibility of the distal end portion of the catheter can be secured, and the catheter can be further prevented from being broken. .

[Fourth Embodiment]
Hereinafter, although the catheter of 4th Embodiment is demonstrated, while it is simplified or abbreviate | omitted about the point which is common in the catheter of 1st Embodiment, the catheter of 2nd Embodiment, and the catheter of 3rd Embodiment, in drawing The same symbol is attached.

FIG. 6 is a partially enlarged cross-sectional view of the catheter of the fourth embodiment. In FIG. 6, the catheter tube 90 includes a catheter main body 21 and a distal tip 22. The catheter main body 21 has an inner layer 91 and an outer layer 92 covering the outer periphery of the inner layer 91, and the distal tip 22 has an inner layer 91 extending from the catheter main body 21 and a distal end covering the outer periphery of the inner layer 91. And an outer layer 93.

The radiopaque marker 94 disposed on the distal tip 22 is disposed between the inner layer 91 and the distal outer layer 93, and a gap 95 is provided between the radiopaque marker 94 and the inner layer 91. .

According to this configuration, when the catheter is inserted into the blood vessel and bent due to the gap portion 95 inside the radiopaque marker 94, excessive stress concentration is prevented, and the flexibility of the distal end portion of the catheter is reduced. It can be ensured to prevent breakage of the catheter.

In the present embodiment, the gap portion 95 is provided between the radiopaque marker 94 and the inner layer 91. However, like the catheters of the second to third embodiments, the radiopaque marker is provided. 94 to the outside of the catheter tube 90 in the radiation direction (between the radiopaque marker 94 and the distal outer layer 93), or to both sides of the catheter tube 90 in the radiation direction (radiopaque). May be provided between the sex marker 94 and the inner layer 91 and between the radiopaque marker 94 and the outer tip layer 93). Even in such a case, the same effects as those described in the embodiments can be obtained.

  In the first to fourth embodiments, the configuration in which the radiopaque marker is disposed on the distal tip side has been described. However, the radiopaque marker may be disposed on the catheter tube side. The effect similar to the effect demonstrated by each embodiment is show | played.

  In the first to fourth embodiments, the catheter has been described as being separated into the catheter tube and the tip, but the catheter is configured so that the catheter tube and the tip are formed integrally. In this case, the same effects as those described in the embodiments can be obtained.

Furthermore, in the first embodiment to the fourth embodiment, the shape of the radiopaque marker has been described as a ring shape, but other shapes such as a coil shape and a shape in which a part of the ring shape is cut out may be used. Also good. However, the ring shape can prevent excessive stress concentration, ensure flexibility of the catheter tip, and prevent breakage of the catheter, no matter which direction the tip of the catheter is curved.

DESCRIPTION OF SYMBOLS 1 Catheter 10 Operation part 20, 50, 70, 90 Catheter tube 21 Catheter main body part 22 Tip chip 24, 91 Inner layer 27, 57, 77 Reinforcement member 28, 58, 78 Reinforcement part 29, 59, 79, 93 Outer end layer 30, 60, 80, 94 Radiopaque markers 30a, 60a, 80a Fusion portions 35, 65, 85, 95 Gaps 92 Outer layer

Claims (5)

A tubular body having an inner layer ;
In a catheter provided with a radiopaque marker disposed on the outer periphery of the inner layer of the tubular body,
The catheter, wherein the radiopaque marker is fixed so as to provide a gap between the radiopaque marker and the outer periphery of the inner layer in the radial direction of the tubular body.   The catheter according to claim 1, wherein the gap is provided on both sides in the radial direction with respect to the radiopaque marker. The tubular body further has an outer layer,
The catheter according to claim 1 or 2, wherein the resin of the outer layer penetrates between the marker and the inner layer. In the inside of the tubular body, provided with a reinforcing member arranged along the long axis direction of the tubular body,
The catheter according to any one of claims 1 to 3, wherein the radiopaque marker is fixed to a distal end of the reinforcing member.   The catheter according to claim 4, wherein the void portion is formed to extend to a distal end of the reinforcing member to which the radiopaque marker is fixed.