JP5814530B2 - Medical catheter - Google Patents

Description

  The present invention relates to a medical catheter.

  Conventionally, percutaneous angioplasty has been widely used as a treatment aimed at restoring or improving blood flow to coronary arteries or peripheral blood vessels by expanding the narrowed or obstructed portion of the blood vessel lumen. ing.

  For example, a general operation example of coronary angioplasty (PTCA; Percutaneous Transluminal Coronary Angioplasty) using a balloon catheter as described in Patent Document 1 is as follows.

  First, a guiding catheter is inserted from a puncture site such as the femoral artery, brachial artery, or radial artery, and after passing through the aorta, the tip of the guiding wire is placed at the entrance of the coronary artery.

  Next, the guide wire inserted through the guide wire lumen of the balloon catheter is advanced beyond the stenotic site of the coronary artery, the balloon catheter is inserted along the guide wire, and the balloon is further aligned with the stenosis. .

  Subsequently, when a device such as an indeflator is used, pressure fluid is supplied to the balloon via the inflation lumen of the balloon catheter, and the balloon is inflated to expand the stenosis.

  In this way, after the stenosis is expanded, the balloon is deflated and the balloon catheter is removed from the body. This completes PTCA.

  By the way, for a lesion with a very high degree of stenosis or a chronic total occlusion lesion, the guide wire is difficult to advance beyond the stenosis site and treatment may not be performed. In such a case, a microcatheter or a penetrating catheter is used, and the advancement of the guide wire beyond the stenosis site is realized.

  PTCA may also require local administration of a therapeutic substance to the stenotic site. For example, the treatment etc. which dissolve a thrombus by locally administering a thrombolytic agent are mentioned. In such cases, an infusion catheter that administers the therapeutic substance locally is used.

  Among treatment subjects using medical dilatation catheters, dilation treatment is special for chronic total occlusion lesions (CTO (Chronic Total Occlusion) lesions) in coronary arterial blood vessels. Passing operation to the part is extremely difficult.

JP 2002-291900 A

  By the way, for a special lesion such as a CTO lesion, a guide wire passes through the lesion while being backed up by a microcatheter or a penetration catheter. Furthermore, since an expansion treatment device such as a balloon catheter or a stent delivery catheter easily passes through the stenosis, the microcatheter or the penetration catheter may pass through the stenosis in advance.

  Further, the guide wire may be exchanged after the microcatheter or the penetration catheter or the like passes through the stenosis.

  Thus, when a flexible catheter passes through a lesion having severe stenosis, the radiopaque marker arranged at the distal end of the catheter may be caught on the stenosis.

  When such a situation occurs, if the catheter is forcibly pulled out, there is a very high risk that the radiopaque marker contained at the distal end of the catheter will fall off the catheter and remain in the body. As countermeasures, generally, the catheter cross-sectional area is increased by increasing the outer diameter of the shaft tube of the catheter, or the outer layer resin at the distal end of the catheter is stiffened to break the distal end of the catheter. The strength is improved.

  However, such a measure is unsuitable for a catheter for passing through a severely bent blood vessel or a severe stenotic lesion.

  The present invention has been made to solve the above problems. And the objective is to provide the medical catheter which prevented omission of the radiopaque marker.

The medical catheter includes a medical tube having one end as a distal end and the other end as a distal end. In this medical catheter, an inner layer surrounding the hollow, a reinforcing layer surrounding the inner layer, an X-ray opaque marker attached on the reinforcing layer, an outer layer surrounding the reinforcing layer and the X-ray opaque marker, a marker stopper, including. The marker stopper is located on at least one side of the distal end side and the distal end side with respect to the radiopaque marker, and is interposed between the reinforcing layer and the outer layer so that the entire circumference of the reinforcing layer or a part of the entire circumference is provided. Fixed to surround .

  In this case, the movement of the radiopaque marker is restrained by the marker stopper. Therefore, the radiopaque marker does not fall off from the medical catheter. In addition, if the radiopaque marker is difficult to drop off, it is not necessary to form the outer layer with a high hardness material and increase the thickness of the outer layer in order to prevent the radiopaque marker from falling off. Therefore, the outer layer is formed of a highly flexible material, or the thickness of the outer layer is reduced. Then, such a medical catheter can easily enter smoothly even in a blood vessel that is severely bent (in short, a highly flexible medical catheter is completed).

  Even if the medical catheter is pulled, the marker stopper is fixed to the reinforcing layer, so that the reinforcing layer does not stretch and does not shrink. If such a diameter reduction does not occur, the reinforcing layer does not deviate from the X-ray opaque marker, and the level difference of the X-ray opaque marker based on the reinforcing layer does not increase. Therefore, when a medical catheter is used, a lesion or the like is less likely to be caught with respect to the radiopaque marker. Therefore, the radiopaque marker does not fall off from the medical catheter.

In addition, since the marker stopper is interposed between the reinforcing layer and the outer layer, the marker stopper is fixed to the reinforcing layer before the outer layer is attached, so the marker stopper is attached to the reinforcing layer, the outer layer, and the inner layer. No special processing is required to attach the stopper. This simplifies the manufacture of the medical catheter.

The marker stopper is located on at least one side of the distal end side and the distal end side with respect to the radiopaque marker, and is interposed between the reinforcing layer and the inner layer, so that the entire circumference of the reinforcing layer or one around the entire circumference is provided. You may fix so that it may be covered with a part.

The marker stopper is preferably the same material as the reinforcing layer.

In this case, the marker stopper is firmly fixed to the reinforcing layer by welding or the like. Therefore, the stability of the marker stopper is increased, and the movement of the radiopaque marker is surely stopped. Also, processing such as welding is relatively simple.

  Further, it is preferable that an intermediate layer is interposed between the radiopaque marker and the reinforcing layer, and the reinforcing layer and the intermediate layer are in close contact with each other.

  In this case, the radiopaque marker is firmly embedded in the intermediate layer. Therefore, the X-ray opaque marker becomes difficult to move. Further, the intermediate layer is in close contact with the reinforcing layer, thereby suppressing deformation of the reinforcing layer. Therefore, since the diameter of the reinforcing layer is not further reduced, the level difference of the radiopaque marker based on the reinforcing layer does not increase, and a lesion or the like is not easily caught on the radiopaque marker (that is, X Radiopaque markers do not fall off the medical catheter).

  The radiopaque marker preferably includes a notch.

  In this case, for example, a part of the outer layer located outside the radiopaque marker enters the notch. That is, a part of the outer layer is caught by the radiopaque marker so as to stop the movement of the radiopaque marker. Therefore, the radiopaque marker does not fall further from the medical catheter.

  According to the present invention, the medical catheter prevents dropping of the radiopaque marker while being flexible.

FIG. 3 is a cross-sectional view of a catheter. FIG. 3 is a cross-sectional view of a catheter. FIG. 3 is a cross-sectional view of a catheter. FIG. 3 is a cross-sectional view of a catheter. FIG. 3 is a cross-sectional view of a catheter. FIG. 3 is a perspective view of a radiopaque marker. FIG. 3 is a cross-sectional view of a catheter. FIG. 3 is an enlarged sectional view of a catheter. FIG. 3 is a perspective view of a catheter.

[Embodiment 1]
The following describes one embodiment with reference to the drawings. For convenience, member numbers and symbols may be omitted, but in such a case, other drawings are referred to.

  FIG. 9 is a simple perspective view of a medical catheter 49. The catheter 49 includes a shaft tube 42 that includes a hollow 41 and a hub 47 that is gripped by an operator. Note that openings 43 are formed at both ends of the catheter 49, and an opening entering the body is an opening 43T on the distal end Ts, and an opening located on the opposite side of the opening is an opening 43E on the distal side Es.

  As shown in the cross-sectional views of FIGS. 1 to 3, the shaft tube 42 includes an inner layer 31, a reinforcing layer 32, an outer layer 33, a radiopaque marker 21, and a marker stopper 11. The catheter 49 including the shaft tube 42 shown in FIGS. 1 to 3 is referred to as Example (EX) 1 to Example (EX) 3.

<About inner layer>
The inner layer 31 is a cylindrical body surrounding the hollow 41 connected to both openings 43 (43T and 43E). A guide wire, a chemical solution, and the like pass through the hollow main lumen 41 (in short, inside the inner layer 31).

  The material of the inner layer 31 is preferably a material that improves chemical resistance, antithrombogenicity, and guidewire slidability, such as fluororesin or high-density polyethylene. However, even if it is not a suitable material such as these (that is, a material that does not have the properties required for antithrombogenicity, etc.), the inner layer 31 is coated. The inner layer 31 may have required characteristics.

  The wall thickness of the inner layer 31 is not particularly limited, but it is preferable that the inner layer 31 be thinned within a range in which the inner layer 31 is not broken in order to suppress an increase in the outer diameter of the shaft tube 42 (and thus the catheter 49). It is preferable that the inner layer 31 has a thin thickness within a range where the breaking strength of the inner layer 31 can withstand actual use.

  Further, if the inner layer 31 has a single inner diameter, the inner layer 31 can be easily manufactured. However, for example, in order to improve passage to a chronic total occlusion lesion {CTO (Chronic Total Occlusion) lesion}, the outer diameter of the inner layer 31 is reduced toward the distal side Ts of the catheter 49, and at the same time, The inner diameter may also be reduced.

<Reinforcing layer>
The reinforcing layer 32 is, for example, spiral and surrounds (covers) the inner layer 31. The reinforcing layer 32 is not particularly limited as long as it has a structure capable of improving kink resistance. For example, the reinforcing layer 32 may be a metal coil, metal braid, metal core wire, resin coil, resin braid, resin wire, or the like. Further, the reinforcing layer 32 may be secondarily drilled with a laser or the like.

<About the outer layer>
The outer layer 33 is a cylindrical body that surrounds (covers) the reinforcing layer 32 (the outer layer 33 may enter between the strands of the reinforcing layer 32 and contact the inner layer 31). The material of the outer layer 33 is not particularly limited as long as it is a resin tube or the like. For example, polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer, or the like can be given.

  Note that the outer layer 33 is preferably formed by connection of resins of various hardnesses so as to cause a change in rigidity gradually. Furthermore, the outer diameter of the outer layer 33 may become small as the catheter 49 goes to the front end side Ts in the catheter 49, for example in order to further improve the permeability to a CTO lesion. Furthermore, it is preferable that the outer layer 33 is formed of a flexible material.

<About X-ray opaque marker>
The radiopaque marker 21 is disposed in the vicinity of the opening 43T on the distal end Ts of the catheter 49. The material of the radiopaque marker 21 is not particularly limited as long as it is substantially a radiopaque material. Therefore, if it is a metal or resin which has radiopacity, those types will not be specifically limited.

  The shape of the radiopaque marker 21 is not particularly limited, but is preferably a hollow ring shape. This is because the hollow ring-shaped X-ray opacity marker 21 is easy to visualize because it looks the same when viewed from any radial direction of the ring under X-ray contrast. . Further, the radiopaque marker 21 can be easily manufactured if it is in a ring shape.

  The number of radiopaque markers 21 is not particularly limited, and only one radiopaque marker may be included, or two or more radiopaque markers may be included.

  Further, the method of attaching the X-ray opaque marker 21 in the shaft tube 42 is not particularly limited, and for example, the X-ray opaque marker 21 may be attached to the reinforcing layer 32 or the like by being caulked. (The X-ray opaque marker 21 may be in close contact with the reinforcing layer 32, the outer layer 33, the intermediate layer 34 described later, or the like. Contact state).

<About X-ray opaque marker stopper>
The radiopaque marker stopper [marker stopper] 11 is located on at least one side of the distal end Ts and the distal side Es with respect to the radiopaque marker 21. The marker stopper 11 is fixed to the reinforcing layer 32 (the fixing means that the marker stopper 11 does not shift relative to the reinforcing layer 32, and the method of fixing to the reinforcing layer 32 is as follows. It may be direct or indirect, and may be various contacts such as adhesion, pressure bonding, sticking, adhesion, bonding, etc., and is not particularly limited.

  In Example 1, the marker stoppers 11 are positioned on the tip side Ts and the terminal side Es with reference to the radiopaque marker 21. In Example 2, the marker stopper 11 is positioned on the tip side Ts with the X-ray opaque marker 21 as a reference. In Example 3, the marker stopper 11 is positioned on the terminal side Es with reference to the radiopaque marker 21.

  If the marker stopper 11 fixed to the reinforcing layer 32 is thus present, for example, when the catheter 49 is used, the following phenomenon occurs, and the radiopaque marker 21 is attached to the shaft tube 42, As a result, it does not fall out of the catheter 49 (that is, the dropping strength of the radiopaque marker 21 is improved).

  For example, if the marker stopper 11 is disposed on the tip side Ts with respect to the radiopaque marker 21, the radiopaque marker 21 to be moved when the shaft tube 42 is pulled is Hit the stopper 11. Therefore, the radiopaque marker 21 does not fall out of the shaft tube 42 and eventually the catheter 49.

  Further, for example, when the marker stopper 11 is arranged on the terminal side Es with respect to the X-ray opaque marker 21, when the shaft tube 42 is pulled, X-ray opaque for the CTO lesion or the like. The marker 21 itself is less likely to be caught directly (in short, the marker stopper 11 hits the CTO lesion etc., and the CTO lesion etc. hardly hits the radiopaque marker 21). Therefore, the radiopaque marker 21 does not fall out of the shaft tube 42 and eventually the catheter 49.

  Various shapes of the marker stopper 11 are conceivable. For example, a ring shape that covers the entire periphery of the spiral reinforcing layer 32 may be used, or a shape that covers a part of the entire periphery of the reinforcing layer 32 (for example, a block shape) may be used. In short, the shape is not particularly limited as long as it is a marker stopper 11 that comes into contact with the X-ray opaque marker 21 to be moved or blocks an object to touch the X-ray opaque marker 21.

  However, if the marker stopper 11 covers the entire periphery of the reinforcing layer 32, the movement of the X-ray opaque marker 21 can be reliably suppressed, and the object to be touched by the X-ray opaque marker 21 can be reliably blocked. Is preferable. (For example, when the marker stopper 11 is disposed on the tip side Ts with reference to the radiopaque marker 21 and the marker stopper 11 covers the entire periphery of the reinforcing layer 32, the tip side of the shaft tube 42 The effect of preventing the radiopaque marker 21 from dropping from Ts is reliably increased).

  Further, if the marker stopper 11 is fixed (connected) to the reinforcing layer 32, the reinforcing layer 32 is difficult to extend while reducing its diameter (while reducing its diameter) even if the shaft tube 42 is pulled. Therefore, when the diameter of the reinforcing layer 32 is reduced, the reinforcing layer 32 does not deviate from the X-ray opaque marker 21, and a step due to the difference between the X-ray opaque marker 21 and the reinforcing layer 32 does not occur. . In short, there is no difference in level (step) from the reinforcing layer 32 to the X-ray opaque marker 21 that occurs when the X-ray opaque marker 21 and the reinforcing layer 32 are separated. Then, such a step does not happen to hit a CTO lesion or the like.

  Therefore, if such a step (clearance) does not occur, the X-ray opaque marker 21 does not fall out of the reinforcing layer 32 and hence the shaft tube 42 due to the X-ray opaque marker 21 hitting the CTO lesion or the like. .

  Further, if the radiopaque marker 21 does not fall off from the shaft tube 42 in this way, the hardness of the outer layer 33 is increased or the thickness of the outer layer 33 is prevented in order to prevent the radiopaque marker 21 from falling off. It is not necessary to take measures such as increasing Therefore, the hardness of the outer layer 33 can be reduced and the flexibility of the shaft tube 42 can be increased, or the thickness of the outer layer 33 can be reduced to make the shaft tube 42 thinner (thinner diameter). For this reason, the catheter 49 that can easily enter even in a blood vessel that is severely bent is completed.

  That is, the catheter 49 including the shaft tube 42 can be easily delivered or passed through a lesion having severe stenosis such as a CTO lesion on the distal side in a bent blood vessel. Furthermore, the radiopaque marker 21 disposed on the distal end Ts of the catheter 49 is less likely to be caught by a CTO lesion or the like. Even if it is caught, the radiopaque marker 21 (in other words, The tip tip including the radiopaque marker 21 does not fall off.

  In addition, the area connected to the reinforcement layer 32 increases, so that the length of the marker stopper 11 along the axial direction of the shaft tube 42 is long. Therefore, when the shaft tube 42 is pulled, the diameter of the reinforcing layer 32 becomes difficult to be reduced, and as a result, a step due to the divergence between the radiopaque marker 21 and the reinforcing layer 32 does not occur, and the step is a CTO lesion. Nothing will happen.

  However, if the length of the marker stopper 11 is excessively long, the flexibility of the shaft tube 42 is impaired. Therefore, the length of the marker stopper 11 may be variously changed according to the purpose (for example, the tip of the shaft tube 42). However, when high flexibility is required, the marker stopper 11 may be relatively short, and the marker stopper 11 may be disposed close to the radiopaque marker 21).

  The material of the marker stopper 11 is not particularly limited. However, considering that the marker stopper 11 and the reinforcing layer 32 are in close contact with each other, it is preferable that the marker stopper 11 is formed of the same material as the reinforcing layer 32.

  This is because when the reinforcing layer 32 is formed of the same material as that of the marker stopper 11, the marker stopper 11 can be welded to the reinforcing layer 32 (in addition, such welding makes the marker stopper 11 and the reinforcing layer 32 strong and It can be fixed stably and the welding process is relatively simple). Therefore, the effect of preventing the radiopaque marker 21 from falling off from the tip side Ts of the shaft tube 42 is high.

  The details of Examples 1 to 3 shown in FIGS. 1 to 3 are as follows.

<Example 1 (EX1)>
As shown in FIG. 1, the shaft tube 42 according to the first embodiment includes an inner layer 31 covered with a reinforcing layer 32. The radiopaque marker 21 is attached to the reinforcing layer 32 arranged outside the inner layer 31. The outer diameter of the reinforcing layer 32 covered with the inner layer 31 is 0.50 mm, and the outer diameter of the radiopaque marker 21 after attachment is 0.54 mm. Example 2 to Example 6 are also equivalent). Further, the marker stopper 11 is attached to the distal end Ts and the distal end Es of the shaft tube 42 with reference to the radiopaque marker 21.

  The material of the marker stopper 11 is a SUS wire {a metal wire formed of stainless steel (SUS304)} having an outer diameter of 0.04 mm. And this SUS line is wound around the reinforcing layer 32 and welded to the reinforcing layer 32 by the YAG laser device (Note that the marker stoppers 11 in the following Examples 2 to 6 are also the same SUS line as described above. Produced by laser welding).

  Thereafter, the outer layer 33 covers the reinforcing layer 32 on which the radiopaque marker 21 and the marker stopper 11 are mounted, whereby the shaft tube 42 is completed.

<Example 2 (EX2)>
As shown in FIG. 2, the shaft tube 42 according to the second embodiment includes the inner layer 31 covered with the reinforcing layer 32. The radiopaque marker 21 is attached to the reinforcing layer 32 arranged outside the inner layer 31. Further, the marker stopper 11 is attached to the tip side Ts of the shaft tube 42 with reference to the radiopaque marker 21.

  Thereafter, the outer layer 33 covers the reinforcing layer 32 on which the radiopaque marker 21 and the marker stopper 11 are mounted, whereby the shaft tube 42 is completed.

<Example 3 (EX3)>
As shown in FIG. 3, the shaft tube 42 according to the third embodiment includes the inner layer 31 covered with the reinforcing layer 32. The radiopaque marker 21 is attached to the reinforcing layer 32 arranged outside the inner layer 31. Further, the marker stopper 11 is attached to the terminal side Es of the shaft tube 42 with reference to the radiopaque marker 21.

  Thereafter, the outer layer 33 covers the reinforcing layer 32 on which the radiopaque marker 21 and the marker stopper 11 are mounted, whereby the shaft tube 42 is completed.

  In addition, the tensile breaking strength of the shaft tube 42 of these Examples 1 to 3 was measured. And the tensile breaking strength of the shaft tube which has not attached the marker stopper 11 in Examples 1 to 3 was used as a comparative example, and compared with the tensile breaking strength of the shaft tube 42 of Examples 1 to 3.

  Then, the tensile breaking strength of the shaft tube 42 of Examples 1 to 3 was higher than the tensile breaking strength of the shaft tube of the comparative example (Note that the tensile strength of the shaft tube 42 of Examples 4 to 6 described later is higher). The breaking strength was also higher than the tensile breaking strength of the shaft tube of the comparative example).

  In addition, the measurement of the tensile breaking strength first grasped the location of the hand part 1 mm from the X-ray impermeable marker with a pin vice using a tensile compression tester {Strograph EII manufactured by Shimadzu Corporation). And it carried out by measuring the intensity | strength when the ring marker hooked on the pin vise fell by pulling a shaft tube on the conditions of the distance between chuck | zippers of 70 mm, and the tension speed of 300 mm / min.

[Embodiment 2]
A second embodiment will be described. In addition, about the member which has the same function and effect as the member used in Embodiment 1, the same code | symbol is attached and the description is abbreviate | omitted.

  In the shaft tube 42 in the first to third embodiments described in the first embodiment, a detailed description will be given between the outer layer 33 and the inner layer 31 so as to surround the reinforcing layer 32 (in other words, the reinforcing layer 32 and the outer layer 33). In between, the marker stopper 11 is arranged. However, the present invention is not limited to this.

  For example, in the shaft tube 42 of Example 4 as shown in FIG. 4, the outer layer 33 and the inner layer 31 will be covered by the reinforcing layer 32 in detail (in other words, the inner layer 31 and the reinforcing layer 32 may be covered with each other). In between, the marker stopper 11 may be arranged. The details of Example 4 are as follows.

<Example 4 (EX4)>
As shown in FIG. 4, the shaft tube 42 according to the fourth embodiment includes the inner layer 31 covered with the reinforcing layer 32. However, the marker stopper 11 is disposed with respect to the inner layer 31 before the inner layer 31 is covered with the reinforcing layer 32. That is, the reinforcing layer 32 covers the inner layer 31 covered with the marker stopper 11. And the SUS line (material used as the marker stopper 11) covered with the reinforcement layer 32 is welded to the reinforcement layer 32 by the YAG laser apparatus.

  Thereafter, the radiopaque marker 21 is arranged on the terminal side Es with respect to the marker stopper 11 (in other words, on the tip side Ts of the shaft tube 42 with respect to the radiopaque marker 21, Marker stopper 11 is arranged).

  Thereafter, the outer layer 33 covers the reinforcing layer 32 to which the radiopaque marker 21 is attached, whereby the shaft tube 42 is completed.

  Even in the shaft tube 42 (and thus the catheter 49) of the second embodiment as described above, the marker stopper 11 is positioned on the tip side Ts with reference to the radiopaque marker 21 (that is, the second embodiment). The marker stopper 11 is arranged similarly to the shaft tube 42). Therefore, the effect resulting from the marker stopper 11 being included in the shaft tube 42 as described in the first embodiment is exhibited.

  Of course, the marker stopper 11 interposed between the inner layer 31 and the reinforcing layer 32 may be positioned on the distal side Es with reference to the radiopaque marker 21, and the distal side Ts and the distal side Es It may be located on both sides. And even if it is such a shaft tube 42, there exists an effect resulting from the marker stopper 11 being included in the shaft tube 42 as demonstrated in Embodiment 1. FIG.

[Embodiment 3]
A third embodiment will be described. In addition, about the member which has the function and effect similar to the member used in Embodiment 1 * 2, the same code | symbol is attached, and the description is abbreviate | omitted.

  In the first and second embodiments, the shaft tube 42 includes the inner layer 31, the reinforcing layer 32, and the outer layer 33, and three layers. However, the layer structure is not limited to this. For example, as shown in FIG. 5, an intermediate layer 34 may be included in addition to the inner layer 31, the reinforcing layer 32, and the outer layer 33. More specifically, Example 5 shown in FIG. 5 is as follows.

<Example 5 (EX5)>
As shown in FIG. 5, the shaft tube 42 of the fifth embodiment includes the inner layer 31 covered with the reinforcing layer 32. Further, the intermediate layer 34 covers at least a part of the reinforcing layer 32 disposed outside the inner layer 31. For example, in the circumferential direction and the axial direction of the shaft tube 42, the intermediate layer 34 covers a part of the reinforcing layer 32 only in the same range as the range in which the radiopaque marker 21 is disposed.

  The radiopaque marker 21 is attached so as to cover the intermediate layer 34 (in short, at least a part of the radiopaque marker 21 is in close contact with the intermediate layer 34; And various contact states such as crimping or sticking). Further, the marker stopper 11 is attached to the tip side Ts of the shaft tube 42 with reference to the radiopaque marker 21.

  Thereafter, the outer layer 33 covers the reinforcing layer 32 on which the radiopaque marker 21 and the marker stopper 11 are mounted, whereby the shaft tube 42 is completed.

  Here, the intermediate layer 34 will be described in detail. The intermediate layer 34 is not particularly limited as long as it has a hardness higher than that of the outer layer 33, but is preferably a resin in consideration of adhesion between the outer layer 33 and the inner layer 31. For example, if the intermediate layer 34 is made of the same resin as that of the outer layer 33, it can be welded to the outer layer 33. If such welding is performed, the radiopaque marker 21 is connected to the outer layer 33. The intermediate layer 34 is wrapped. Therefore, the radiopaque marker 21 is unlikely to fall off from the distal end Ts of the catheter 49.

  For example, even if the intermediate layer 34 is a resin different from the inner layer 31, if the intermediate layer 34 is subjected to various treatments such as surface treatment or modification, both layers 34 -31 adhesion increases. If the adhesion between the intermediate layer 34 and the inner layer 31 is increased in this way, the X-ray opaque marker 21 is attached to the intermediate layer 34 by, for example, caulking. It becomes difficult to displace not only the intermediate layer 34 but also the inner layer 31. As a result, the radiopaque marker 21 is less likely to drop off from the distal end Ts of the catheter 49.

  The intermediate layer 34 may be an adhesive. If the intermediate layer 34 is an adhesive, the adhesive entering the gap between the inner layer 31 and the reinforcing layer 32 strengthens the adhesion between the layers 31 and 32. Therefore, if the radiopaque marker 21 is attached to the intermediate layer 34 that is an adhesive, the radiopaque marker 21 is less likely to be displaced not only in the intermediate layer 34 but also in the inner layer 31. . As a result, the radiopaque marker 21 is less likely to drop off from the distal end Ts of the catheter 49.

  In addition, when the intermediate layer 34 is an adhesive, the composition and chemical structure of the adhesive and the curing type are not particularly limited. For example, from the viewpoint of composition and chemical structure, urethane type, silicone type, epoxy type, or cyanoacrylate type adhesives are preferably used. From the viewpoint of curing type, for example, a two-component mixed type, UV curable type, water absorption curable type, or heat curable type adhesive is preferably used.

  In the case where the intermediate layer 34 is an adhesive, for example, the adhesive preferably has a hardness that does not discontinuously change the rigidity of the joint portion before and after the joint portion when cured. In addition, it is preferable that the adhesive is selected in consideration of the material, dimensions, rigidity, and the like of the joining site. Moreover, in order to make a joining site | part comparatively thin diameter, the joining part may be heat-processed. For example, in the case where the adhesive is a difficult-to-adhere material such as polyolefin, the bonding portion may be bonded after plasma treatment with oxygen gas or the like to improve the adhesiveness.

  Further, the intermediate layer 34 is interposed between the shaft tube 42 of the third embodiment as described above, that is, the radiopaque marker 21 and the reinforcing layer 32, and the reinforcing layer 32 and the intermediate layer 34 are in close contact with each other. Even in the shaft tube 42 (and thus the catheter 49), the marker stopper 11 is positioned on the tip side Ts with reference to the radiopaque marker 21. Therefore, the effect resulting from the marker stopper 11 being included in the shaft tube 42 as described in the first embodiment is exhibited.

  Needless to say, the marker stopper 11 may be positioned on the terminal side Es with respect to the radiopaque marker 21, or may be positioned on both sides of the tip side Ts and the terminal side Es. And even if it is such a shaft tube 42, there exists an effect resulting from the marker stopper 11 being included in the shaft tube 42 as demonstrated in Embodiment 1. FIG.

[Embodiment 4]
A fourth embodiment will be described. In addition, about the member which has the function and effect similar to the member used in Embodiment 1-3, the same code | symbol is attached and the description is abbreviate | omitted.

  The shape of the radiopaque marker 21 is not particularly limited. For example, the ring-shaped radiopaque marker 21 may have a notch 21D as shown in FIG. In addition, Example 6 shown in FIG. 7 is as follows.

<Example 6 (EX6)>
As shown in FIG. 7, the shaft tube 42 of the sixth embodiment includes an inner layer 31 covered with the reinforcing layer 32. The radiopaque marker 21 is attached to the reinforcing layer 32 arranged outside the inner layer 31. A plurality of notches 21D are formed in the X-ray opaque marker 21 by the YAG laser device.

  Further, the marker stopper 11 is attached to the tip side Ts of the shaft tube 42 with reference to the radiopaque marker 21.

  Thereafter, the outer layer 33 covers the reinforcing layer 32 on which the radiopaque marker 21 and the marker stopper 11 are mounted, whereby the shaft tube 42 is completed.

  Here, the notch 21 </ b> D is any hole, crack, groove, or all that can contact the outer layer 33 and the inner layer 31 such as a pitch interval when the X-ray impermeable marker 21 has a coil structure. The structure of The term “contact” as used herein includes all contacts including chemical bonding such as welding, physical bonding such as pressure bonding, adhesion, or adhesion.

  When such a notch 21D is formed in the radiopaque marker 21, as shown in FIG. 7, the resin forming the outer layer 33 flows into the notch 21D when the outer layer 33 to be coated later melts. The resin that has flowed in functions like a ridge (an effect based on such a function is referred to as an anchor effect). Then, the tensile breaking strength at the distal end portion of the catheter 49 including the X-ray opaque marker 21 is improved without increasing the outer diameter of the outer layer 33.

  Further, the number of the cutouts 21D and the arrangement of the cutouts 21D are not particularly limited. For example, in FIG. 6, four notches 21D are formed, but there may be one or a plurality other than four. Further, the notches 21D may be formed along the circumference (entire circumference) of the cylindrical X-ray opaque marker 21 or may be irregularly formed.

  Further, the shaft tube 42 including the intermediate layer 34 may also include the X-ray opaque marker 21 into which the notch 21D is inserted. In this way, the intermediate layer 34 is in close contact with a part of the outer layer 33 approaching through the notch 21 </ b> D of the radiopaque marker 21 that surrounds the intermediate layer 34. Therefore, the outer layer 33 and the intermediate layer 34 wrap the X-ray opaque marker 21, and the X-ray opaque marker 21 is less likely to drop off from the distal end Ts of the catheter 49.

  Even in the shaft tube 42 (and thus the catheter 49) of the fourth embodiment as described above, the marker stopper 11 is located on the distal end side Ts with reference to the radiopaque marker 21 with the notch 21D. Therefore, the effect resulting from the marker stopper 11 being included in the shaft tube 42 as described in the first embodiment is exhibited.

  Of course, the marker stopper 11 may be positioned on the terminal side Es with respect to the radiopaque marker 21, or may be positioned on both sides of the tip side Ts and the terminal side Es. And even if it is such a shaft tube 42, there exists an effect resulting from the marker stopper 11 being included in the shaft tube 42 as demonstrated in Embodiment 1. FIG.

[Other embodiments]
The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the shaft tube 42, as shown in FIG. 8, when the marker stopper 11 is disposed on the terminal side Es with reference to the radiopaque marker 21, the edge of the marker stopper 11 (particularly the shaft tube 42). It is preferable to round the edge facing the terminal side Es. With this configuration (in short, chamfering is necessary), when the catheter 49 is pulled, a CTO lesion or the like is hardly caught on the marker stopper 11. Even when the marker stopper 11 is disposed on the tip side Ts with the radiopaque marker 21 as a reference, the edge of the marker stopper 11 may be rounded.

  Further, when the marker stopper 11 is disposed on the tip side Ts with reference to the X-ray opaque marker 21, it is preferable that the thickness of the marker stopper 11 is larger than the thickness of the X-ray opaque marker 21. More specifically, when the inner wall surface of the ring-shaped marker stopper 11 and the inner wall surface of the ring-shaped X-ray opaque marker 21 are in contact with the outer wall surface of the reinforcing layer 32, for example, from the outer wall surface of the marker stopper 11 The length of the reinforcing layer 32 to the outer wall surface is preferably longer than the length from the outer wall surface of the radiopaque marker 21 to the outer wall surface of the reinforcing layer 32.

  In this case, in order for the radiopaque marker 21 to fall off the shaft tube 42, it must move so as to ride on the marker stopper 11, but its movement becomes extremely difficult (in short The radiopaque marker 21 does not fall out of the shaft tube 42 and thus the catheter 49).

  However, if the marker stopper 11 is excessively thick, the outer diameter of the distal end Ts of the catheter 49 may be increased, or the flexibility of the distal end Ts of the catheter 49 may be reduced. Therefore, if these are taken into consideration, the thickness of the marker stopper 11 may be approximately the same as the thickness of the radiopaque marker 21.

  Further, the position of the marker stopper 11 is not particularly limited in the radial direction of the radiopaque marker 21. For example, as shown in Examples 1 to 3, Example 5, and Example 6 (see FIGS. 1 to 3, 5, and 7), the marker stopper 11 is provided between the reinforcing layer 32 and the outer layer 33. The marker stopper 11 may be positioned between the inner layer 31 and the reinforcing layer 32 as shown in Example 4 (see FIG. 4).

  However, the marker stopper 11 is preferably located between the reinforcing layer 32 and the outer layer 33 in terms of ease of processing in manufacturing the shaft tube 42.

  Further, the inner layer 31 may be disposed over the entire length of the catheter 49. Further, the distal side Ts of the inner layer 31 may be disposed only halfway from the distal side Ts of the outer layer 33 to the middle of the distal side Es of the catheter 49 (in short, the entire length of the outer layer 33 is equal to the total length of the inner layer 31). It may be longer than that).

  Furthermore, the inner layer 31 is preferably formed of a single member from the viewpoint of ease of manufacture. However, for example, when the change in rigidity of the shaft tube 42 is added by the inner layer 31, the inner layer 31 may be formed by joining a plurality of members near the middle of the catheter 49.

  Further, it is preferable that a hydrophilic coating that facilitates insertion into the blood vessel or the guide catheter is applied to the outer surface (surface) of the catheter 49. That is, it is preferable that a hydrophilic coating that exhibits lubricity is applied to at least a part of the outer layer 33 that is assumed to be attached to blood when it comes into contact with blood.

  Further, in the outer layer 33, the portion and the length to which the hydrophilic coating is applied may be appropriately changed according to the purpose of use of the catheter 49.

  The type of hydrophilic coating is not particularly limited, and poly (2-hydroxyethyl methacrylate), polyacrylamide, polyvinyl pyrrolidone, or a maleic anhydride polymer (for example, methyl vinyl ether maleic anhydride maleate). Examples of the coating material include hydrophilic polymers such as maleic anhydride copolymers such as acid copolymers. Further, the coating method is not particularly limited.

  Further, the type of the catheter 49 is not particularly limited. For example, the catheter 49 is used in peripheral angioplasty, PTCA (Percutaneous Transluminal Coronary Angioplasty), or percutaneous angioplasty (PTA) when performing valvuloplasty or the like. It may be a microcatheter, a penetration catheter for penetrating a stenosis, an infusion catheter capable of administering a therapeutic substance to a local site, a guiding catheter, or the like.

  When the catheter 49 is a balloon catheter, depending on the purpose of use, a hydrophobic coating may be applied to the outer surface of the balloon so that the balloon does not slip when the balloon is expanded. The kind of the hydrophobic coating is not particularly limited, and a hydrophobic polymer such as silicone is preferably used.

11 X-ray opaque marker stopper [Marker stopper]
21 X-ray opaque marker 21D Notch 31 Inner layer 32 Reinforcement layer 33 Outer layer 34 Intermediate layer 41 Main lumen [hollow]
42 Shaft tube 43 Opening 43T End opening 43E End opening 47 Hub 49 Catheter

Claims (5)

In a medical catheter including a medical tube having one end as a tip and the other end as a terminal,
An inner layer surrounding the hollow,
A reinforcing layer surrounding the inner layer;
A radiopaque marker attached on the reinforcing layer;
An outer layer surrounding the reinforcing layer and the radiopaque marker;
With a marker stopper,
Including
The marker stopper is located on at least one side of the distal end side and the distal end side with respect to the radiopaque marker, and is interposed between the reinforcing layer and the outer layer so as to surround the entire periphery of the reinforcing layer. Or the medical catheter fixed to a reinforcement layer so that a part in the perimeter may be enclosed. In a medical catheter including a medical tube having one end as a tip and the other end as a terminal,
An inner layer surrounding the hollow,
A reinforcing layer surrounding the inner layer;
A radiopaque marker attached on the reinforcing layer;
An outer layer surrounding the reinforcing layer and the radiopaque marker;
With a marker stopper,
Including
The marker stopper is located on at least one of the distal end side and the distal end side with respect to the radiopaque marker, and is interposed between the reinforcing layer and the inner layer so as to surround the entire periphery of the reinforcing layer. Or a medical catheter fixed to a reinforcing layer so as to be covered by a part of the entire circumference.   The medical catheter according to claim 1, wherein the marker stopper is made of the same material as the reinforcing layer. The medical catheter according to any one of claims 1 to 3, wherein an intermediate layer is interposed between the radiopaque marker and the reinforcing layer, and the reinforcing layer and the intermediate layer are in close contact with each other.   The medical catheter according to any one of claims 1 to 4, wherein the radiopaque marker includes a notch.

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