JP7279466B2 - catheter - Google Patents

Description

The present invention relates to catheters.

Catheters that can be inserted into body cavities such as blood vessels are known. A doctor injects a drug solution or the like into a body cavity using a catheter.
In general, a catheter consists of a resin tube and a reinforcing layer that reinforces the tube in order to ensure pushability when inserting the catheter and durability against internal pressure when injecting a drug solution. be. For example, Patent Literature 1 describes that the reinforcing layer is formed by braiding a plurality of strands into a mesh.

JP-A-2007-82802

On the other hand, recent catheters are required to be inserted into smaller diameter blood vessels, and in order to ensure operability and safety, the tip of the catheter is required to be thinner and more flexible. It has been demanded.
However, it is not always easy to reduce the diameter of the distal end of the catheter and ensure flexibility due to the presence of the reinforcing layer.

The present invention has been made in view of the above problems, and is intended to reduce the diameter of the distal end of the catheter while improving the pushability during insertion of the catheter and the durability against internal pressure during injection of drug solutions and the like. To provide a catheter that can ensure flexibility and flexibility.

The present invention comprises a resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer, and a reinforcing layer formed by winding a wire and enclosed in the resin layer around the lumen. and a long catheter main body having a first reinforcing layer, wherein the wire constituting the distal reinforcing layer on the distal side of the first reinforcing layer extends behind the rear end side of the first reinforcing layer The wires forming the end-side reinforcing layer have a smaller diameter than the wires forming the end-side reinforcing layer, and the wires forming the tip-side reinforcing layer have a diameter smaller continuously or stepwise toward the tip, and A ring-shaped marker fixed to the tip-side reinforcing layer and enclosed in the resin layer is further provided, and the diameter of the strand constituting the part of the tip-side reinforcing layer to which the marker is fixed is increased. Provided is a catheter in which the rate of change is smaller than the rate of change in the diameter of the wires constituting the proximal end of the distal reinforcing layer to the proximal end of the marker fixed to the distal reinforcing layer. It is.
Further, the present invention is configured by winding a resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer, and a wire, and is included in the resin layer around the lumen. a first reinforcing layer that is a reinforcing layer; The diameter of the wire constituting the rear end side reinforcing layer is smaller than that of the wire constituting the tip side reinforcing layer, and the outer curvature of the cross section of the wire constituting the tip side reinforcing layer is smaller than the inner curvature of the cross section, A portion of the cross section of the wire constituting the tip-side reinforcing layer, which has a large curvature, is embedded in the inner layer, and a portion of the cross section, which has a small curvature, is the above-mentioned A catheter is provided that is embedded in the outer layer.
Further, the present invention is configured by winding a resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer, and a wire, and is included in the resin layer around the lumen. a first reinforcing layer that is a reinforcing layer; The catheter main body has a second reinforcing layer, which is the reinforcing layer, inside the first reinforcing layer, The second reinforcing layer extends from the tip of the first reinforcing layer, and the wire constituting the part of the second reinforcing layer that overlaps the tip side reinforcing layer of the first reinforcing layer extends toward the tip. Catheters are provided that have a continuous or stepped reduction in diameter.
Further, the present invention is configured by winding a resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer, and a wire, and is included in the resin layer around the lumen. a first reinforcing layer that is a reinforcing layer; The catheter main body has a second reinforcing layer, which is the reinforcing layer, inside the first reinforcing layer, The second reinforcing layer extends from the tip of the first reinforcing layer, and the wire constituting the part of the second reinforcing layer extending from the first reinforcing layer is continuous toward the tip. A catheter is provided that has a tapered or stepped diameter.

According to the present invention, it is possible to secure thinness and flexibility at the distal end of the catheter while improving the pushability at the time of insertion of the catheter and the durability against the internal pressure at the time of injecting a medical solution or the like. can be done.

FIG. 1 is an overall view of a catheter according to this embodiment. FIG. 2 is a longitudinal sectional view of the catheter according to this embodiment. FIG. 3 is a partially enlarged view of FIG. 2 showing the distal end of the catheter. FIG. 4 is a diagram showing a cross-sectional shape of a strand corresponding to the rear end side small diameter region among the strands constituting the first blade in the present embodiment. FIG. 5 is a diagram showing a modification in which the wires forming the first blade are enclosed in the outer layer. FIG. 6 is a diagram showing a modification in which the tip side of the wire constituting the second blade has a small diameter.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in all the drawings, the same reference numerals are given to the same constituent elements, and the description thereof will be omitted as appropriate.
The various components of the catheter according to this embodiment do not need to be independent of each other. one component being part of another component, part of one component overlapping part of another component, etc.
Further, in the following description, the tip refers to the tip of the catheter body 10 (see FIG. 1) (the left end as viewed in the drawing shown in FIG. 1), and the rear end or proximal end of the catheter body 10. Refers to the proximal or posterior end (the right end as viewed in the view shown in FIG. 1). Furthermore, the axis refers to the axis of the catheter body 10 .

<About the outline of the catheter according to the present embodiment>
First, an outline of a catheter 100 according to this embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is an overall view of the catheter 100 according to this embodiment, FIG. 2 is a longitudinal sectional view of the catheter 100 according to this embodiment, and FIG. 3 is a partially enlarged view of FIG. FIG. 2 shows the distal end of catheter 100. FIG.

As shown in FIG. 1 , a catheter 100 according to this embodiment is composed of a long catheter body 10 and a gripping portion 90 provided at the proximal end of the catheter body 10 . The grasping portion 90 has a connecting portion 91 for inserting a liquid injection device (not shown) such as a syringe or an injector from its proximal end. A thread groove is formed on the outer periphery of the connecting portion 91 so that the syringe can be detachably fixed. A hub 92 is provided in the central portion of the grip portion 90 . A hollow is formed in the gripping portion 90 so as to penetrate the gripping portion 90 from the distal end to the proximal end in the axial direction. A proximal end portion of the catheter body 10 is fixed to the grip portion 90 . The hub 92 has two vanes 93 facing each other across the axis of the grip 90 . By rotating the wings 93 about the axis of the grasping part 90, it is possible to perform a torque operation to rotate the entire catheter body 10, and to adjust the direction of the tip of the catheter body 10 that has entered the body cavity. can. A protector 94 is provided on the distal end side of the hub 92 and covers the proximal end portion of the catheter body 10 .

The catheter 100 is typically inserted into the body from the artery at the root of the femur of a subject, and is passed through the aorta and common carotid artery to perforator branches branching from the internal carotid artery, the external diameter artery, etc., and the tip of the catheter body 10 is inserted. It is used to perform a procedure to insert the buttocks. Therefore, the catheter body 10 is manufactured with a length corresponding to such a procedure. However, the present invention is not limited to this example, and the catheter 100 may have a length suitable for insertion into other sites.

As shown in FIG. 2 , the catheter main body 10 includes a small diameter region 21 on the distal end side, a large diameter region 22 on the rear end side, and a lumen 31 that connects the proximal end of the small diameter region 21 to the tip of the large diameter region 22 and will be described later. and an enlarged diameter region 23 that expands the outer shape of the catheter main body 10 in a tapered shape toward the proximal end. As a result, a liquid such as a drug solution can be smoothly supplied to the distal end of the catheter body 10 through the lumen 31 . Alternatively, the inner diameter of the catheter body 10 may be set to a constant diameter, and only the outer shape of the catheter body 10 may be tapered in a diameter-enlarging region 23 from the proximal end of the small-diameter region 21 to the distal end of the large-diameter region 22. good.

The catheter body 10 also includes a resin layer 30 including an inner layer 32 having a lumen 31 and an outer layer 33 formed around the inner layer 32, and a resin layer 30 embedded in the resin layer 30 and arranged around the lumen 31. and a reinforcing layer 40 .
The reinforcing layer 40 includes a first blade 41 arranged on the outer peripheral surface of the inner layer 32 from the base end of the large diameter region 22 to the tip of the small diameter region 21, and and a second blade 42 arranged on the outer periphery of the first blade 41 over a predetermined position in the vicinity, and the first blade 41 and the second blade 42 are arranged around the lumen 31 along the axial direction. Consists of wound wires. In addition, as a method of winding each blade in the present embodiment, a method of braiding a plurality of strands into a mesh is adopted, but a method of winding one or more strands into a coil is adopted. may Furthermore, when a plurality of strands are braided into a mesh, each strand is composed of one strand in this embodiment, but at least a part of each strand is composed of a plurality of strands. The same applies to the case of adopting the method of winding the wires in a coil shape. The wire is preferably made of a metallic material such as stainless steel.
In addition, the catheter 100 according to the present embodiment is manufactured by forming the inner layer 32, then winding the first blade 41 around the outer periphery of the inner layer 32, then winding the second blade 42, and then forming the outer layer 33. be done. However, in forming the outer layer 33, the formation is divided into two stages, and after forming the first stage of the outer layer 33, the second blade 42 is wound around the outer periphery of the outer layer 33 formed in the first stage, and then The outer layer 33 may be formed by forming the second stage of the outer layer 33 in the second stage and fusing the outer layer 33 formed in the second stage to the outer layer 33 formed in the first stage.
Further, the catheter body 10 has a ring-shaped marker 50 made of, for example, a radiopaque metal material. The markers 50 are included in the resin layer 30 and fixed to the distal end of the first blade 41 and arranged around the lumen 31 , and fixed to the distal end of the second blade 42 in the lumen 31 . and a rear end side marker 52 arranged around. Each marker may have a shape with a slit in the axial direction or the circumferential direction to give flexibility. Further, the rear end side marker 52 of the markers 50 is not limited to the radiopaque metallic material, and may be made of a material different from the metallic material, such as an adhesive.
Further, the catheter body 10 has a distal tip 60 made of resin that is connected to the distal end of the catheter body 10 . The distal tip 60 has a distal lumen 61 with an open distal end, and the distal lumen 61 communicates with the lumen 31 .

As shown in FIG. 3 , in the present embodiment, the wire constituting the first blade 41 (first reinforcing layer) has a diameter of , is smaller than the diameter of the wire (the wire constituting the rear-end reinforcing layer) in the large-diameter region 22 .
As a result, while improving the pushability at the time of insertion of the catheter body 10 and the durability against the internal pressure at the time of injection of a drug solution, etc., the tip portion of the catheter body 10 (the portion corresponding to the small diameter region 21) It is possible to ensure a small diameter and flexibility.
In order to achieve this effect, for example, a flat wire having a rectangular cross section (hereinafter simply referred to as a cross section) cut along a plane perpendicular to the axial direction of the strand to be cut is used as the first blade 41. The shape of the cross section is not limited to a circular shape, such as being adopted for the strands constituting the . That is, the cross-sectional area of the wire in the small-diameter region 21 should be smaller than the cross-sectional area of the wire in the large-diameter region 22 .
Here, in the present invention, the small cross-sectional area of the wire in the small-diameter region 21 means a cross-sectional shape obtained by removing a part of the cross-section based on the cross-section of the wire in the large-diameter region 22 by mechanical polishing or the like. It refers to being realized by becoming Therefore, in the present invention, the reduction in the cross-sectional area of the wire is synonymous with the reduction in the geometrical moment of inertia of the wire with respect to bending in the axial direction. In the present invention, the reduction in the cross-sectional area of the wires forming the first blade 41 in this embodiment is simply expressed as the diameter of the wires being reduced.
In addition, in this embodiment, the tip region of the catheter body 10 (the region where the first blade 41 extends from the tip of the second blade 42) has the small diameter region 21 and the large diameter region 22, and these regions However, there may be no distinction between these regions, ie, the catheter body 10 may be configured with a constant diameter in the tip region. In this case, the length in the axial direction of the region in which the wire constituting the first blade 41 is made small may be any length, but the length is the length in the axial direction of the tip region. It is preferably less than half the length.
Furthermore, as described above, at least a portion of each strand constituting the first blade may be composed of a plurality of strands. In this case, all of the plurality of strands are It is preferable that the diameter of the small-diameter region 21 is smaller than the diameter of the large-diameter region 22 . However, in at least one of the plurality of strands, the diameter in the small-diameter region 21 may be smaller than the diameter in the large-diameter region 22 .

A more detailed description will be given below.

<Regarding the diameter of the wire constituting the first blade>

As shown in FIG. 3, in the present embodiment, the wire constituting the first blade 41 extends from the wire 41a at the proximal end of the small-diameter region 21 to the wire 41b in front of the distal marker 51 ( The diameter is continuously reduced toward the distal end over the rear end side small diameter region 211) shown in FIG.
As a result, it is possible to reduce the occurrence of stress concentration at the distal end portion (the portion corresponding to the small diameter region 21) of the catheter body 10, so that by further reducing the sudden change in stiffness, it is possible to reduce the stress during insertion of the catheter body 10 The pushability can be further improved, and the strength of the catheter main body 10 can be increased by further suppressing stress concentration at the tip.
In order to achieve this effect, the wires in the rear end side small diameter region 211 of the wires forming the first blade 41 may be gradually reduced in diameter toward the tip. Here, stepwise means that the diameters of the wires change, for example, the diameters of a plurality of wires between the wires 41a and 41b of the wires shown in FIG. 3 become the same. It means that there is a part that does not.
Note that, in the present embodiment, even in a region where the diameter of the wire is continuously reduced, the distance between the centers of the wire constituting the first blade 41 is constant. That is, the pitch of the first blades 41 is constant. The same may be applied to the case where the first blade 41 is configured by winding one or a plurality of strands into a coil.

In addition, the strands constituting the first blade 41 are reduced in diameter continuously or stepwise (including simply reducing the diameter), and are realized by connecting a plurality of strands with different diameters. Each strand is formed one after the other.
Further, the method for reducing the diameter of the wires is not limited to mechanical polishing, and methods other than mechanical polishing such as chemical polishing may be employed. The strands constituting the first blade 41 may be polished before the first blade 41 is wound around the inner layer 32, or after the first blade 41 is wound and the outer layer 33 is polished. may be done before forming the

Further, as shown in FIG. 3, in the present embodiment, of the strands constituting the first blade 41, the position where the tip side marker 51 is fixed (the position where the tip side marker 51 contacts the inner peripheral surface of the tip side marker 51) The wire 41c in the small-diameter region 212 on the distal end side shown in FIG. 3 has a constant diameter.
As a result, the contact area between the inner peripheral surface of the marker and the outer peripheral surface of the wire 41c when the tip end marker 51 is fixed by caulking or the like is increased, and the fixing strength of the tip end marker 51 can be increased. In addition, the difference in the distance from the axis of the catheter body 10 to the outer periphery of the distal marker 51 (difference in height of the distal marker 51) is suppressed when the distal marker 51 is fixed to the wire 41c. It is possible to make it difficult to generate projections of the outer layer near 51 .
In order to achieve these effects, it is preferable that the wire 41c has a constant diameter. After the diameter is gradually reduced (the cross-sectional area of the wire 41c is decreased toward the tip), the change rate of the diameter (cross-sectional area) of the wire 41c is calculated from the wire 41a to the wire 41b. may be made smaller than the change rate of the diameter of If the rate of change of these diameters is not constant, the average value of the rate of change of each diameter should have such a relationship.
Further, in the present embodiment, the diameter of the strand of wire 41c that is positioned closest to the proximal side of the distal marker 51 is the same as the diameter of the strand of wire 41b. However, of the wires 41c, the diameter of the wire positioned closest to the proximal side of the distal marker 51 may be different from the diameter of the wire 41b. It is preferable that the diameter of the wire located on the most proximal side of the side marker 51 is smaller than that of the wire 41b. That is, it is preferable that the diameter of the strand of wire 41c that is positioned closest to the proximal side of tip-side marker 51 is equal to or smaller than the diameter of strand 41b.

Further, in the present embodiment, the wire constituting the first blade 41 has a constant diameter on the proximal end side of the catheter body 10 relative to the wire 41d in front of the wire 41a at the proximal end of the small diameter region 21. ing.
Thereby, the large diameter region 22 of the catheter body 10 of the first blade 41 can be made robust.
Moreover, in the present embodiment, the diameter of the wire 41a is the same as the diameter of the wire 41d, but the diameter is not limited to this. The wire 41a may have a smaller diameter than the wire 41d.
Note that each of the strands 41a to 41d in the present embodiment does not necessarily indicate a different strand, and the axial direction of the first blade 41 composed of one or a plurality of strands. showing different positions.

<Regarding the cross-sectional shape of the wire constituting the first blade>
Next, the cross-sectional shape of the wire corresponding to the rear end side small diameter region 211 among the wire constituting the first blade 41 will be described with reference to FIG. 4 . 4 is a diagram showing the cross-sectional shape of the wire corresponding to the rear end side small diameter region 211 of the wire constituting the first blade 41 in this embodiment, and the figure is the broken line in FIG. It is an enlarged view of the enlarged area I indicated by .

As shown in FIG. 4, the cross-sectional shape of the wire corresponding to the rear end side small diameter region 211 (the wire from the wire 41a to the wire 41b shown in FIG. 3) among the wire constituting the first blade 41 is , the curvature of the outer side of the wire is smaller than the curvature of the inner side of the wire (the radius of curvature is larger). For example, as shown in FIG. The curvature of outer peripheral surface 414 is smaller than that of surface 418 . The magnitude of the curvature (curvature radius) in this embodiment refers to comparison of the average value of the curvature of the surface to be compared when the curvature of the surface to be compared is not constant.
As a result, when the wire corresponding to the rear-end small-diameter region 211 of the wire constituting the first blade 41 is bent toward the inner side of the catheter body 10 along the axis, the bending stress increases. It is possible to suppress the curvature of the outer side of the wire, make it difficult to create a starting point of separation from the outer layer 33 on the outer side of the wire, and make it difficult to separate the outer layer 33 on the distal end side of the catheter body 10 .

Further, as shown in FIG. 4, the cross-sectional shape of the wire corresponding to the rear end side small diameter region 211 among the wires constituting the first blade 41 has an outer curvature that decreases toward the tip. ing. More specifically, the curvature of the outer peripheral surface decreases (the radius of curvature increases) in the order of outer peripheral surface 414, outer peripheral surface 413, outer peripheral surface 412, and outer peripheral surface 411. FIG.
As a result, in the wire corresponding to the rear end side small diameter region 211 among the wires constituting the first blade 41, it is difficult to create a starting point of separation from the outer layer 33 on the tip side where more flexibility is required. be able to.

In addition, as shown in FIG. 4 , in the present embodiment, the wire constituting the first blade 41 is embedded in the inner layer 32 , and the outer layer 33 is in contact with both the wire and the inner layer 32 . As a result, the surface area of the outer layer 33 that contacts both the wire and the inner layer 32 can be increased, making it difficult for the inner layer 32 and the outer layer 33 to separate from each other.
In particular, in the present embodiment, in the rear end side small diameter region 211, the outer peripheral surface (for example, the outer peripheral surface 411 to the outer peripheral surface 414) having a large curvature of the wire constituting the first blade 41 is embedded in the outer layer, and the wire is embedded in the outer layer. The inner peripheral surfaces (for example, the inner peripheral surfaces 415 to 418) having a small linear curvature are embedded in the inner layer 32 . As a result, when the resin outer layer 33 is formed with the first blade 41 wound around the inner layer 32, voids are less likely to occur around the inner peripheral surface and the outer layer 33 is less likely to peel off. can.

Moreover, as shown in FIG. 5 , the wires forming the first blade 41 may be wrapped in the outer layer 33 .
Even in this way, voids are less likely to occur around the inner peripheral surface with a small curvature, and the outer layer 33 is less likely to peel off.
In addition, since the cross-sectional shape of each strand denoted by the same reference numeral is the same as that shown in FIG. 4, the description thereof will be omitted.

<Regarding application of the present invention to the second blade>
Next, with reference to FIG. 6, a modified example in which the wire configuration of the present embodiment described above, that is, the configuration in which the tip side of the wire constituting the first blade 41 has a small diameter is applied to the second blade 42. will be explained. FIG. 6 is a diagram showing a modification in which the tip end side of the wire constituting the second blade 42 has a small diameter.
In the following description, of the description related to the strands constituting the second blade 42 in this modified example, the part that overlaps with the description related to the strands constituting the first blade 41 in the above-described embodiment is The description is omitted as appropriate, and each configuration of the wire forming the first blade 41 is applicable to the wire forming the second blade 42 as long as there is no contradiction.

As with the first blade 41 in the above-described present embodiment, the rear end of the wire constituting the second blade 42 (first reinforcing layer) extends from the base end of the rear end marker 52 along the axial direction. The strands (the strands constituting the tip side reinforcing layer, including the strands 42a to 42b shown in FIG. 6) in a predetermined region toward the side are the strands constituting the second blade 42. The diameter of the wire may be smaller than that of the wire (the wire constituting the rear end side reinforcing layer) on the rear end side along the axial direction from the base end of the predetermined region of the wire.
As a result, by reducing abrupt changes in stiffness at the tip of the catheter body 10 (a predetermined region, that is, the boundary between the first blade 41 and the second blade 42), the pushability of the catheter body 10 during insertion is improved. (Pushability) can be improved, stress concentration at the boundary can be suppressed, and the strength of the catheter body 10 can be increased.
The predetermined region may be a region extending from the proximal end of the rear end side marker 52 along the axial direction, but the length of the region is equal to the axial center of the large diameter region 22. It is preferably less than half the length of the direction. Furthermore, in addition to this modified example, the configuration of the present embodiment (the strands in the region from the proximal end of the distal end marker 51 of the strands constituting the first blade 41 toward the rear end side along the axial direction) is smaller than the wire on the rear end side along the axial direction from the base end of the region of the wire constituting the first blade 41). , the length in the axial direction of the region in which the wires forming the second blade 42 have a small diameter is the length in the axial direction of the region in which the wires forming the first blade 41 have a small diameter in the present embodiment. Longer than length is preferred.

In particular, like the wires shown from wire 42a to wire 42b in FIG. can be
As a result, abrupt changes in stiffness at the distal end (boundary) of the catheter body 10 are further reduced, thereby further improving the pushability of the catheter body 10 during insertion and further suppressing stress concentration at the boundary. The strength of the catheter body 10 can be increased by
In order to achieve this effect, the wires in a predetermined region of the wires forming the second blade 42 may be gradually reduced in diameter toward the tip.

Furthermore, as shown in FIG. 6, in the present modification, of the wire constituting the second blade 42, the position where the rear end marker 52 is fixed (contacts the inner peripheral surface of the rear end marker 52) position) has a constant diameter.
As a result, when the rear end marker 52 is fixed by caulking or the like, the contact area between the inner peripheral surface of the marker and the outer peripheral surface of the wire 42c is increased, and the fixing strength of the rear end marker 52 can be increased. . Also, when the rear end marker 52 is fixed to the wire 42c, the difference in distance from the axis of the catheter body 10 to the outer circumference of the rear end marker 52 (difference in height of the rear end marker 52) is suppressed, It is possible to make it difficult for the protrusion of the outer layer near the rear end side marker 52 to occur.
In order to achieve these effects, it is preferable that the wire 42c has a constant diameter. After reducing the diameter in stages, the rate of change in the diameter of the wire 42c may be made smaller than the rate of change in the diameter of the wire from the wire 42a to the wire 42b.
In particular, in this modified example, of the wires forming the first blade 41, the wire 41g at the position where the rear end marker 52 is fixed also has a constant diameter. As a result, the effects described above, that is, the effect of suppressing the difference in the distance from the axis of the catheter body 10 to the outer circumference of the rear end marker 52 and the effect of making it difficult to generate protrusions on the outer layer near the rear end marker 52 , are produced. can increase
Further, as in the above-described present embodiment, it is preferable that the diameter of the strand of wire 42c that is positioned closest to the proximal side of the rear end marker 52 is equal to or less than the diameter of the strand of wire 42a. Furthermore, it is preferable that the diameter of the strand of wire 41g that is positioned closest to the proximal side of the rear end marker 52 is equal to or smaller than the diameter of the strand of wire 41e.

Further, in the present modification, among the wires forming the first blade 41, the wires corresponding to the predetermined region (including the wires 41e to 41f shown in FIG. 6) are replaced with Among the strands of wire constituting one blade 41, the diameter of the strand is smaller than that of the strand on the rear end side along the axial direction from the base end of the predetermined region.
As a result, abrupt changes in stiffness at the distal end (boundary) of the catheter body 10 are further reduced, thereby further improving the pushability of the catheter body 10 during insertion and further suppressing stress concentration at the boundary. The strength of the catheter body 10 can be increased by

In addition, of the wires forming the first blade 41, a portion of the wire extending from the tip of the second blade 42 (for example, from the wire 41h of the wires of the first blade 41 shown in FIG. 6 wire up to the wire 41i) may be continuously reduced in diameter.
As a result, by further reducing abrupt changes in the stiffness of the catheter body 10 in the region extending from the predetermined region to the distal end, the operability of the catheter 100 is further improved, and stress concentration at the boundary is further suppressed. The strength of the main body 10 can be increased.

It should be noted that the present embodiment and its modifications described above can be appropriately combined without departing from the gist of the present invention.

This embodiment includes the following technical ideas.
(1)
A resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer; an elongated catheter body having a reinforcing layer;
The wires forming the front end reinforcing layer on the front end side of the first reinforcing layer have a smaller diameter than the wires forming the rear end reinforcing layer on the rear end side of the first reinforcing layer. ,
catheter.
(2)
The wire constituting the tip-side reinforcing layer has a diameter that decreases continuously or stepwise toward the tip,
The catheter according to (1) above.
(3)
A ring-shaped marker fixed to the tip side reinforcing layer and included in the resin layer,
The change rate of the diameter of the wire constituting the portion of the tip-side reinforcing layer to which the marker is fixed is the base of the marker fixed to the tip-side reinforcing layer from the base end of the tip-side reinforcing layer. is smaller than the change rate of the diameter of the wire constituting the end,
The catheter according to (2) above.
(4)
The diameter of the wire constituting the portion of the tip side reinforcing layer to which the marker is fixed is constant,
The catheter according to (3) above.
(5)
The diameter of the wire constituting the rear end side reinforcing layer is constant,
The catheter according to any one of (1) to (4) above.
(6)
The cross section of the wire is circular,
The curvature of the outer side of the cross section of the wire constituting the tip side reinforcing layer is smaller than the inner curvature of the cross section.
The catheter according to any one of (1) to (5) above.
(7)
the outer curvature of the cross-section of the wire constituting the tip-side reinforcing layer decreases toward the tip;
The catheter according to (6) above.
(8)
wherein the wire constituting the tip-side reinforcing layer is enclosed in the outer layer;
The catheter according to (6) or (7) above.
(9)
A portion of the cross section of the wire constituting the tip-side reinforcing layer having a large curvature is embedded in the inner layer, and a portion of the cross section having a small curvature is embedded in the outer layer.
The catheter according to (6) or (7) above.
(10)
The catheter body has a second reinforcing layer, which is the reinforcing layer, inside the first reinforcing layer,
The second reinforcing layer extends from the tip of the first reinforcing layer,
The catheter according to any one of (1) to (8) above.
(11)
The wire constituting the part of the second reinforcing layer that overlaps the tip side reinforcing layer of the first reinforcing layer has a diameter that decreases continuously or stepwise toward the tip,
The catheter according to (10) above.
(12)
The wire constituting the part of the second reinforcing layer extending from the first reinforcing layer has a diameter that decreases continuously or stepwise toward the tip,
The catheter according to (10) or (11) above.

10 catheter body 21 small diameter region 22 large diameter region 23 expanded diameter region 30 resin layer 31 lumen 32 inner layer 33 outer layer 40 reinforcing layer 41 first braid 41a wire 41b wire 41c wire 41d wire 41e wire 41f wire 41g wire Wire 41h Wire 41i Wire 42 Second blade 42a Wire 42b Wire 42c Wire 50 Marker 51 Distal marker 52 Rear marker 60 Distal tip 61 Distal lumen 90 Grip portion 91 Connecting portion 92 Hub 93 Wing 94 Protector 100 Catheter 211 Rear end side small diameter region 212 Tip side small diameter region 411 Outer peripheral surface 412 Outer peripheral surface 413 Outer peripheral surface 414 Outer peripheral surface 415 Inner peripheral surface 416 Inner peripheral surface 417 Inner peripheral surface 418 Inner peripheral surface I Enlarged region

Claims (6)

A resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer; an elongated catheter body having a reinforcing layer;
The wires forming the front end reinforcing layer on the front end side of the first reinforcing layer have a smaller diameter than the wires forming the rear end reinforcing layer on the rear end side of the first reinforcing layer. ,
The wire constituting the tip-side reinforcing layer has a diameter that decreases continuously or stepwise toward the tip,
further comprising a ring-shaped marker fixed to the tip side reinforcing layer and included in the resin layer,
The change rate of the diameter of the wire constituting the portion of the tip-side reinforcing layer to which the marker is fixed is the base of the marker fixed to the tip-side reinforcing layer from the base end of the tip-side reinforcing layer. is smaller than the change rate of the diameter of the wire constituting the end,
catheter. The diameter of the wire constituting the portion of the tip side reinforcing layer to which the marker is fixed is constant,
A catheter according to claim 1 . A resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer; an elongated catheter body having a reinforcing layer;
The wires forming the front end reinforcing layer on the front end side of the first reinforcing layer have a smaller diameter than the wires forming the rear end reinforcing layer on the rear end side of the first reinforcing layer. ,
the outer curvature of the cross-section of the wire constituting the tip-side reinforcing layer is smaller than the inner curvature of the cross-section and decreases toward the tip,
A portion of the cross section of the wire constituting the tip-side reinforcing layer having a large curvature is embedded in the inner layer, and a portion of the cross section having a small curvature is embedded in the outer layer.
catheter. A resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer; an elongated catheter body having a reinforcing layer;
The wires forming the front end reinforcing layer on the front end side of the first reinforcing layer have a smaller diameter than the wires forming the rear end reinforcing layer on the rear end side of the first reinforcing layer. ,
The catheter body has a second reinforcing layer, which is the reinforcing layer, inside the first reinforcing layer,
The second reinforcing layer extends from the tip of the first reinforcing layer,
The wire constituting the part of the second reinforcing layer that overlaps the tip side reinforcing layer of the first reinforcing layer has a diameter that decreases continuously or stepwise toward the tip,
catheter. A resin layer including an inner layer having a lumen and an outer layer formed on the outer periphery of the inner layer; an elongated catheter body having a reinforcing layer;
The wires forming the front end reinforcing layer on the front end side of the first reinforcing layer have a smaller diameter than the wires forming the rear end reinforcing layer on the rear end side of the first reinforcing layer. ,
The catheter body has a second reinforcing layer, which is the reinforcing layer, inside the first reinforcing layer,
The second reinforcing layer extends from the tip of the first reinforcing layer,
The wire constituting the part of the second reinforcing layer extending from the first reinforcing layer has a diameter that decreases continuously or stepwise toward the tip,
catheter. The diameter of the wire constituting the rear end side reinforcing layer is constant,
6. A catheter according to any one of claims 1-5.

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