TW202039024A - An inner tube, a catheter and method for producing an inner tube - Google Patents

Abstract

An inner tube used for a medical catheter, wherein the inner tube have a marker section relatively reduces the regular reflection amount of an ultrasonic wave as compared with other portions of an outer peripheral surface formed on an outer surface, the marker section includes a first marker portion provided on the half of an outer peripheral surface and a second marker section provided on the other half of the outer peripheral surface, and the marker section has a plurality of arc-shaped grooves extending around the central axis of the inner tube and includes a portion where the groove included in the first marker portion and the groove included in the second marker portion are not continuous with each other.

Description

Inner tube, catheter and method for manufacturing inner tube

The present invention relates to an inner tube, a catheter, and a method of manufacturing the inner tube. This case is based on the Japanese Special Application No. 2019-033301 filed on February 26, 2019, claiming priority and citing its content here.

As a vascular access that takes a large amount of blood from the body of an artificial dialysis patient to a dialyzer for efficient hemodialysis, there is known a dialysis device that directly connects arteries and veins to allow large amounts of blood to pass through. Dedicated blood vessel (shunt tube). During hemodialysis, a large amount of blood is taken from the shunt tube, and metabolic waste, excess water or electrolytes are removed from the taken blood, thereby dialysis a large amount of blood in a short time.

The shunt and the blood vessels near the shunt may be narrowed due to neointimal proliferation or thrombus. For such a stenosis, in order to re-dilate to ensure the blood flow in the shunt tube or to restart the blood flow in the shunt tube, PTA (Percutaneous Transluminal Angioplasty) is performed. In the case of PTA, a catheter with a balloon installed at the front end is inserted into the shunt tube or a narrow part of a blood vessel near the shunt tube, and the balloon is inflated at the narrow part to expand the narrow part.

In recent years, a method called ultrasound guided PTA has also been used to replace the use of vascular imaging agents and confirm the position of the balloon under X-ray fluoroscopy to perform PTA. In the case of ultrasonic guided PTA, the position of the balloon at the tip of the catheter is confirmed by ultrasound, and the balloon is inserted into the narrow part of the shunt tube, and the balloon is expanded to expand the narrow part. As far as ultrasonic wave guide PTA is concerned, it has the advantage of being able to protect patients from the side effects of vascular imaging agents. In addition, it has the advantage of being able to prevent the patient from radiation exposure. In addition, the ultrasonic wave guide PTA can be carried out only by using relatively inexpensive ultrasonic diagnostic equipment, and there is no need to install expensive X-ray diagnostic equipment or special operating rooms that block X-rays, or do not need to wear heavy and stuffy Advantages of X-ray protective clothing.

As a catheter used for PTA in an ultrasonic waveguide, a catheter having a structure with a marking portion in which the reflection state of ultrasonic waves is different from other parts is known (for example, refer to Patent Document 1). [Prior Technical Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2016/031071

[The problem to be solved by the invention]

In the catheter described in the aforementioned patent document, since the marking portion is formed by laser processing or cutting processing, the marking portion is thinner than other portions where the marking portion is not provided, and therefore the mechanical strength is easily reduced. On the other hand, if the outer diameter of the catheter is increased by increasing the thickness in order to ensure the mechanical strength of the indicator portion, the flexibility of the catheter will be impaired. In addition, if the outer diameter of the catheter is increased, it cannot be inserted into the narrow part of the shunt tube, and treatment cannot be performed.

The present invention was completed in view of this situation, and aims to provide an inner tube that can detect the position in the body by irradiating ultrasonic waves and is not easily damaged. Moreover, the purpose is to provide a catheter equipped with such an inner tube. In addition, it is also aimed at providing a manufacturing method capable of easily manufacturing such an inner tube. [Technical means to solve the problem]

In order to solve the aforementioned problems, one aspect of the present invention is: an inner tube for use in medical catheters; characterized in that: the outer peripheral surface of the inner tube is provided with the amount of regular reflection of the ultrasonic wave relative to the outer peripheral surface The other part of the marking part is less, and the marking part includes: a first marking part, which is provided on one side of the outer peripheral surface; and a second marking part, which is provided on the other side of the outer peripheral surface The half-circumferential surface of the said marking portion is provided with a plurality of arc-shaped grooves extending around the central axis of the inner tube, and includes: the grooves contained in the first marking portion and the grooves contained in the second marking portion Is a discontinuous part.

One aspect of the present invention may also be configured such that: on the inner peripheral surface of the inner tube, a convex portion overlapping with the groove is provided in a field of view viewed from a direction perpendicular to the central axis along the groove, and is similar to the The convex line part overlapping the groove of the first indicator portion and the convex line portion overlapping the groove of the second indicator portion are not continuous.

An aspect of the present invention may also be configured such that the protruding stripe portion on the inner peripheral surface side of the first indicator portion and the protruding stripe portion on the inner peripheral surface side of the second indicator portion are perpendicular to the The visual field observed in the direction of the central axis of the inner tube does not overlap.

An aspect of the present invention may also be configured such that: the indicator portion has: a first area where the plurality of grooves are close to each other; and a second area where the interval between the plurality of grooves is greater than that of the first area. width.

According to one aspect of the present invention, the groove may extend in the circumferential direction of the outer peripheral surface.

An aspect of the present invention may also be configured such that the pattern formed by the plurality of grooves included in the first indicator portion and the pattern formed by the plurality of grooves included in the second indicator portion are mutually related Consistent.

An aspect of the present invention may also be configured such that the pattern formed by the plurality of grooves included in the first indicator portion and the pattern formed by the plurality of grooves included in the second indicator portion are mutually related different.

In addition, one aspect of the present invention provides: a catheter having: the inner tube; an outer tube through which the inner tube is inserted; and a balloon provided at the end of the outer tube; the inner tube The aforementioned marking part is provided in the part overlapping with the aforementioned airbag.

One aspect of the present invention may also be configured to include a guide cable inserted through the inner tube.

In addition, one aspect of the present invention provides: a method of manufacturing an inner tube, comprising: using a first mold that is complementary to the first marking portion and a second mold that is complementary to the second marking portion, A step of forming a plurality of grooves corresponding to the first indicator portion and the second indicator portion by hot pressing on the outer peripheral surface of the resin hose.

An aspect of the present invention may also be configured as a manufacturing method including a step of inserting a metal core into the hose before the step of forming the groove.

As other aspects, the present invention includes the following aspects.

[1] An inner tube for use in a medical catheter; it is characterized in that: on the outer peripheral surface of the inner tube, there is provided a marking portion that makes the amount of regular reflection of ultrasonic waves less than other parts of the outer peripheral surface. The marking part includes: a first marking part, which is provided on one half of the outer peripheral surface; and a second marking part, which is provided on the other half of the outer peripheral surface. The marking part is It has a plurality of arc-shaped grooves extending around the central axis of the inner tube, and includes: the grooves included in the first indicator portion and the grooves included in the second indicator portion are discontinuous portions.

[2] The inner tube according to [1], wherein the inner peripheral surface of the inner tube is provided with a convex line overlapping the groove in a field of view seen from a direction perpendicular to the central axis along the groove In the portion, the protruding stripe portion overlapping with the groove of the first indicator portion and the protruding strip portion overlapping with the groove of the second indicator portion are not continuous.

[3] The inner tube according to [2], wherein the ridge portion on the inner peripheral surface side of the first indicator portion and the ridge portion on the inner peripheral surface side of the second indicator portion are The visual field observed in the direction orthogonal to the central axis of the inner tube does not overlap.

[4] The inner tube according to any one of [1] to [3], wherein the marking portion has: a first region, which is a plurality of grooves close to each other; and a second region, which is more In the first region, the interval between the plurality of grooves is wider.

[5] The inner tube according to any one of [1] to [4], wherein the groove extends in the circumferential direction of the outer peripheral surface.

[6] The inner tube according to any one of [1] to [5], wherein the pattern formed by the plurality of grooves included in the first marking portion is the same as the pattern formed by the plurality of grooves included in the second marking portion The patterns formed by a plurality of the aforementioned grooves are consistent with each other.

[7] The inner tube according to any one of [1] to [5], wherein the pattern formed by the plurality of grooves included in the first marking portion is the same as the pattern formed by the plurality of grooves included in the second marking portion The patterns formed by the plural grooves are different from each other.

[8] A catheter comprising: the inner tube described in any one of [1] to [7]; an outer tube through which the inner tube is inserted; and a balloon attached to the end of the outer tube; The aforementioned inner tube has the aforementioned indicator portion at a portion overlapping with the aforementioned airbag.

[9] A catheter having: the inner tube described in any one of [1] to [7]; an outer tube through which the inner tube is inserted; and a balloon attached to the end of the outer tube; The aforementioned airbag has: a cylindrical portion; and a pair of conical portions provided on both sides of the aforementioned cylindrical portion; the aforementioned inner tube has the aforementioned indicator portion at a position overlapping with the aforementioned pair of conical portions.

[10] A catheter having: the inner tube as described in any one of [1] to [7]; an outer tube through which the inner tube is inserted; and a balloon attached to the end of the outer tube; The aforementioned airbag has: a cylindrical portion; and a pair of conical portions provided on both sides of the aforementioned cylindrical portion; the aforementioned inner tube is attached to the front end side of the aforementioned inner tube at a position overlapping the aforementioned conical portion with the aforementioned mark Part, on the outer peripheral surface of the outer tube, there is provided an outer tube marking part that makes the amount of regular reflection of ultrasonic waves less than other parts of the outer peripheral surface of the outer tube. The outer tube marking part is attached to the airbag Adjacent location.

[11] The catheter according to [9] or [10], wherein the inner tube has the indicator portion at a position that does not overlap with the balloon.

[12] The catheter according to any one of [9] to [11], wherein the inner tube has the indicator portion at a position that does not overlap the cylindrical portion.

[13] The catheter according to any one of [8] to [12], which has: a guide cable inserted into the inner tube.

[14] A method for manufacturing an inner tube, which is the method for manufacturing an inner tube according to any one of [1] to [7]; 1. A mold, a second mold having irregularities corresponding to the second indicator portion complementary to each other. A plurality of molds corresponding to the first indicator portion and the second indicator portion are formed by hot pressing on the outer peripheral surface of the resin hose The steps of ditching.

[15] The method of manufacturing an inner tube as described in [14], which includes a step of inserting a metal core into the hose before the step of forming the groove. [Effects of Invention]

According to the present invention, it is possible to provide an inner tube that can detect the position in the body by irradiating ultrasonic waves and is not easily damaged. In addition, it is also possible to provide a catheter equipped with such an inner tube, and a manufacturing method capable of easily manufacturing such an inner tube.

[First Embodiment] Hereinafter, a method of manufacturing the inner tube, catheter, and inner tube according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 11. In addition, in all the following drawings, in order to make the drawings easy to understand, the size or ratio of each constituent element is appropriately different.

＜Inner tube, catheter＞ Fig. 1 is a schematic diagram showing a catheter 1A of this embodiment. The catheter 1A has a catheter hose 2, a balloon 3, and a connector 4. Catheter 1A is a medical catheter used for PTA treatment.

FIG. 2 is a schematic cross-sectional view of the catheter hose 2. As shown in FIG. 2, the catheter hose 2 has an outer tube 21 and an inner tube 22 inserted into the outer tube 21. The outer tube 21 and the inner tube 22 form a double tube structure.

The catheter 1A further has a guide cable GW inserted into the inner tube 22. The guide cable GW is used to guide the catheter hose 2 when the catheter 1A is used.

The outer tube 21 and the inner tube 22 are cylindrical members using a flexible resin material as a forming material. Examples of materials for forming the outer tube 21 and the inner tube 22 include thermoplastic resins such as polyamide, polyester, polyolefin, polyurethane, and polyvinyl chloride. Among them, as a material for forming the outer tube 21 and the inner tube 22, polyamide is preferable because it is safe and has high strength. In addition, as polyamides, polyamide 11, polyamide 12, polyamide 6, polyamide 66 can be used. Among them, due to the good balance of safety, strength, and material cost, polyamide 11 is used. good. In addition, the "safe" material in this embodiment means a material that is biologically safe and does not show toxicity even if it is inserted into the body.

Since the inner peripheral surfaces of the outer tube 21 and the inner tube 22 slide with the guide cable GW, it is preferable to be coated with a low-friction material such as silicone resin or fluororesin.

The outer peripheral surface of the outer tube 21 may be coated with a hydrophilic resin such as polyvinylpyrrolidone and 2-hydroxyethyl methacrylate.

The detailed structure of the inner tube 22 will be described later.

FIG. 3 is a schematic cross-sectional view showing the peripheral structure of the airbag 3. The balloon 3 is attached to the end of the outer tube 21 constituting the catheter hose 2. The inner tube 22 has a front end connected to the cutter 29, and is inserted into the airbag 3 to penetrate therethrough. The airbag 3 is installed in the outer tube 21 and the inner tube 22 in a liquid-tight manner.

The front end of the catheter hose 2 is connected to the cutter 29. The cutter 29 is tied to the tip side of the catheter hose 2 and has a hole 29a through which the guide cable GW can be inserted. The cutter 29 is a protective member with a push-pull shape on the tip side, and is formed of a soft material such as silicone resin, fluororesin, or a low-friction material. The cutter 29 has flexibility that does not damage the inner wall of the blood vessel when the catheter tube 2 is inserted into the blood vessel, and is easy to slip with the inner wall of the blood vessel.

The balloon 3 is a balloon that can be used for general PTA treatment. The airbag 3 is formed of a resin material. As the forming material of the airbag 3, in addition to the same thermoplastic resin as the forming material of the outer tube 21 and the inner tube 22 described above, silicone rubber or latex rubber can also be used.

The airbag 3 can be expanded and deformed by supplying an expansion liquid containing physiological saline as a main component to the internal space 3x. In FIGS. 1 and 3, the state where the balloon 3 is expanded and deformed is shown.

The expanded and deformed airbag 3 has a cylindrical portion 3a and conical portions 3b provided on both sides of the cylindrical portion 3a. In the figure, the length of the cylindrical portion 3a is indicated by the symbol L1. The length L1 is the expandable width of the narrow part in PTA treatment. In addition, the diameter of the cylindrical portion 3a corresponds to the expandable diameter in PTA treatment.

As shown in FIG. 1, the connector 4 is arranged on the other end side of the catheter hose 2. The connector 4 has a first port 4a connected to the outer tube 21 and a second port 4b connected to the inner tube 22. When expanding and deforming the balloon 3, first, the guide cable GW is inserted into the blood vessel in the patient's body to reach the target position. Next, the catheter hose 2 is guided to the target position along the guide cable GW. After the balloon 3 of the catheter tube 2 reaches the target position, the expansion fluid is supplied from the first port 4a. Thereby, the airbag 3 can be expanded and deformed at the target position.

(Inner tube) Hereinafter, the inner tube 22 will be described in further detail. The inner tube 22 has an outer diameter of 1.2 mm, and a wall thickness of 0.1 mm, for example.

As shown in FIG. 3, on the outer peripheral surface of the inner tube 22 and overlapped with the airbag 3, the marking part M which makes the amount of regular reflection of the ultrasonic wave relatively smaller than other parts is provided. A plurality of grooves 221 are provided in each marking portion M.

The depth of the groove 221 is, for example, 50 μm to 300 μm. In addition, the width of the groove 221 is, for example, 50 μm to 300 μm. The edge of the groove 221 may be convex. When the edge of the groove 221 is raised in a convex shape, the depth of the groove refers to the difference in height from the deepest part of the groove to the top of the convex part. In the case where the necessary strength of the inner tube 22 can be ensured and there are no manufacturing defects, the groove 221 is preferably deep.

In the marking portion M, by making the groove 221 to diffuse the ultrasonic wave, the amount of regular reflection of the ultrasonic wave is relatively reduced compared to the portion where the groove 221 is not provided. Therefore, in the ultrasonic wave guide PTA, after the ultrasonic wave irradiated to the catheter is reflected, the amount of the ultrasonic wave reaching the probe receiving the reflected ultrasonic wave is reduced. Therefore, in the echo image using ultrasonic waves, the part corresponding to the groove 221 is displayed darker, and the marking part M displayed as a striped pattern is detected.

The distance (pitch) between the plurality of grooves 221 is preferably 0.5 mm to 20 mm. If the pitch is 0.5% mm or more, it will be easily distinguished from the biological tissue in the echo image. If the pitch is 20 mm or less, the gap between the grooves is appropriate compared to the length of the airbag commonly used in PTA treatment, and it is easy to arrange the grooves 221 at a position overlapping the airbag.

The pitch of the grooves 221 is preferably 2 to 5 mm for easy visual confirmation of the self-echo image.

The indicator portion M has a first area AR1 in which the plurality of grooves 221 are close to each other; and a second area AR2 in which the interval between the plurality of grooves 221 is wider than the first area AR1. The marking portion M shown in the figure has two first areas AR1 and one second area AR2, and is arranged in the order of the first area AR1, the second area AR2, and the first area AR1. The two first regions AR1 are provided so as to overlap the conical portion 3b of the airbag 3.

The first area AR1 and the second area AR2 have different display states in the echo image. Therefore, in the echo image, the positions of the two first areas AR1 are recognized as the marks of the conical portion 3b of the airbag 3, and the positions where the second area AR2 is recognized are the marks of the cylindrical portion 3a of the airbag 3.

4 and 5 are schematic views of the inner tube 22 around the marking portion M. 4 and 5 are schematic diagrams in the visual field orthogonal to the central axis L of the inner tube 22. FIG. 4 is a top view of the inner tube 22, and FIG. 5 is a side view in a field of view tilted 90° to the circumferential direction of the inner tube 22 with respect to FIG.

As shown in FIGS. 4 and 5, a plurality of grooves 221 are provided on the outer peripheral surface of the inner tube 22. The groove 221 is provided on the outer peripheral surface of the cylindrical inner tube 22 and extends in the circumferential direction.

In the first area AR1, a plurality of grooves 221 are arranged at a constant interval (interval P1). In the second area AR2, a plurality of grooves 221 are arranged at a constant interval (interval P2. And P2>P1).

As shown in FIG. 5, the groove 221 is not continuous over the entire circumference of the outer circumferential surface of the inner tube 22, but is in the shape of an arc extending around the central axis L. Specifically, the groove 221 is formed in the circumferential direction of the outer peripheral surface of the inner tube 22 so as to be orthogonal to the central axis L in the visual field of FIG. 5. Therefore, the plurality of grooves 221 do not overlap with each other in the visual field viewed from the direction orthogonal to the central axis L of the inner tube 22.

And, as shown in FIG. 5, the marking portion M includes: a first marking portion M1, which is provided on one half of the outer peripheral surface of the inner tube 22 (indicated by the symbol A); and a second marking portion M2 , Is provided on the half-peripheral surface on the other side of the outer peripheral surface (indicated by symbol B).

The groove 221a included in the first indicator portion M1 and the groove 221b included in the second indicator portion M2 include discontinuous portions. In FIG. 5, the groove 221a included in the first indicator portion M1 and the groove 221b included in the second indicator portion M2 are not continuous. In addition, a part of a plurality of grooves 221a and grooves 221b may be continuous.

Here, the term "discontinuous" means that the end X1 of the groove 221a and the end X2 of the groove 221b are not connected. If the groove 221 a and the groove 221 b are continuous, the groove is formed to cover the entire circumference of the outer peripheral surface of the inner tube 22.

The portion of the inner tube 22 where the groove is formed has lower strength than the portion without the groove. In the inner tube 22 of the present embodiment, the groove 221 is not formed to cover the entire circumference of the outer peripheral surface, but is "discontinuous." In this way, the inner tube 22 has a higher strength than a hose in which a groove is formed to cover the entire circumference of the outer peripheral surface, and therefore, it is relatively difficult to break.

In the inner tube 22, the pattern formed by the plurality of grooves 221a included in the first marking portion M1 and the pattern formed by the plurality of grooves 221b included in the second marking portion M2 are consistent with each other.

FIG. 6 is a cross-sectional view of the inner tube 22, and FIG. 5 is an arrow cross-sectional view of the line VI-VI.

As shown in FIG. 6, the inner peripheral surface of the inner tube 22 is provided with a convex strip portion 222 overlapping the groove 221 in a field of view viewed from a direction perpendicular to the central axis L along the groove 221. In the case where the groove 221a of the first indicator portion M1 and the groove 221b of the second indicator portion M2 are not continuous, the ridge portion 222 overlapping the groove 221a and the ridge portion 222 overlapping the groove 221b are also not continuous.

At the end of the groove 221, a protrusion 223 may be provided.

The convex part 222 and the protrusion part 223 are formed as a result of implementing the manufacturing method of this embodiment mentioned later.

FIG. 7 is a cross-sectional view of the inner tube 22, and is a schematic cross-sectional view of the arrow of the line VII-VII in FIG. 6.

As described above, the plurality of grooves 221 are formed so as not to overlap each other in the visual field viewed from the direction orthogonal to the central axis L of the inner tube 22. Therefore, with regard to the ridge portion 222 formed on the inner peripheral surface of the inner tube 22 overlapping the groove 221, the ridge portion 222a on the side of the first indicator portion M1 and the ridge portion 222b on the side of the second indicator portion M2, There is no overlap in the visual field viewed from the direction orthogonal to the central axis L.

In this way, if the ridge portion 222 does not overlap on the inner peripheral surface side of the inner tube 22 in the field of view viewed from the direction orthogonal to the central axis L, the inner pipe 22 is formed at the position where the ridge portion 222 is formed. The inner diameter W1 is not excessively narrow.

FIG. 8 is a cross-sectional view of a modification of the inner tube, and corresponds to FIG. 7. As shown in the inner tube 23 shown in FIG. 8, if the ridge portion 232 is formed so as not to overlap in the field of view viewed from the direction orthogonal to the central axis L, the inner tube 23 is formed at the position where the ridge portion 232 is formed. The inner diameter Wa will be narrower than the inner diameter W1 in FIG. 7. After the catheter 1A is made using the inner tube 23, in order to insert the guide cable into the inner tube 23, the inner diameter Wa must be a size that allows the guide cable to be inserted.

Therefore, the inner tube 22 having the configuration shown in FIG. 7 can be an inner tube that is thinner than the inner tube 23 and has high versatility.

＜Manufacturing method of inner tube＞ Fig. 9 is a schematic diagram showing a method of manufacturing an inner tube. Regarding the manufacturing method of the inner tube of this embodiment, first, the metal core 30 is inserted into the hose 22A as the raw material of the inner tube.

The hose 22A is a cylindrical member formed of the same material as the aforementioned inner tube 22. The hose 22A is formed with a groove on the outer peripheral surface by hot pressing, thereby becoming the aforementioned inner tube 22.

The core 30 is a metal cable. As the material of the core 30, brass or copper can be used, and copper is preferred. Since the copper system has high thermal conductivity, it is easy to heat the hose 22A during hot pressing. In addition, copper is softer than metals generally used for molds, so the molds are not easily damaged during press processing.

The diameter of the core 30 is smaller than the inner diameter of the hose 22A and larger than the diameter of the guide cable GW used in the catheter 1A.

Next, as shown in FIG. 9, the hose 22A through which the core 30 is inserted is thermally pressed. In this case, the first mold MD1 having the concave and convex portions MD12 corresponding to the first indicator portion M1 and the second mold MD2 having the concave and convex portions MD22 corresponding to the second indicator portion are used.

Specifically, the first mold MD1 and the second mold MD2 have semi-cylindrical grooves MD11 and MD21, respectively. When the semi-cylindrical groove MD11 of the first mold MD1 and the semicylindrical groove MD21 of the second mold MD2 are combined, a cylindrical through hole that penetrates the two molds into an integrated assembly is formed. The formed through hole has a diameter equivalent to the outer diameter of the hose 22A.

The aforementioned concavo-convex portion MD12 included in the first mold MD1 extends around the center axis of the semi-cylindrical groove MD11 included in the first mold MD1, that is, the center axis of the through hole. The aforementioned concavo-convex portion MD22 included in the second mold MD2 extends around the center axis of the semi-cylindrical groove MD21 included in the second mold MD2, that is, the center axis of the aforementioned through hole.

In addition, in FIG. 9, although the concave and convex portions MD12 and MD22 are shown as a plurality of concave and convex portions arranged at equal intervals, respectively, the structure of the concave and convex portions MD12 and MD22 corresponds to the formed first and second indicator portions M1 and M1. Formed by M2.

When using the first mold MD1 and the second mold MD2 to heat the hose 22A, for example, the hose 22A is arranged along the groove MD11 in the first mold MD1, and the hose 22A is arranged along the groove MD21 from above. The second die MD2 is lowered and pressed. Thereby, the shape of the uneven part MD12 and the uneven part MD22 are transferred to the outer peripheral surface of 22 A of hoses, and a plurality of grooves corresponding to the first indicator part M1 and the second indicator part M2 can be formed.

In addition, as the material of the first mold MD1 and the second mold MD2, various materials can be used as long as it is a metal that is generally known as a material of a mold. Among them, since it is easy to process the mold shape and has high thermal conductivity, brass or aluminum alloy is preferable as the material of the first mold MD1 and the second mold MD2.

In addition, during the hot pressing, in response to the stress from the outer circumferential surface of the hose 22A, the inner circumferential surface of the hose 22A protrudes, and the aforementioned ridge portion 222 is formed on the inner circumferential surface of the hose 22A. The processing conditions at the time of hot pressing can adopt various conditions as long as the hose 22A can be thermally deformed so as to form irregularities. For example, as the processing conditions, a mold temperature of 130°C, a surface pressure of 0.04 MPa, and a pressing time of 30 seconds can be selected.

In addition, a protrusion 223 may be formed at a position corresponding to the boundary between the first mold MD1 and the second mold MD2. The protrusion 223 has a function of diffusing ultrasonic waves. Therefore, in the protrusion 223, the amount of regular reflection of the ultrasonic wave is relatively reduced by diffusing the ultrasonic wave. Therefore, in the echo image using ultrasonic waves, the part corresponding to the protrusion 223 is displayed darker, and there is an effect that the marking part M can be clearly displayed.

In the inner tube 22, the pattern formed by the plurality of grooves 221a included in the first marking portion M1 and the pattern formed by the plurality of grooves 221b included in the second marking portion M2 are consistent with each other. Therefore, the grooves of the first mold MD1 and the grooves of the second mold MD2 match.

For example, when laser processing or cutting is performed on the outer peripheral surface of the hose 22A to form grooves to form the marking portion, the grooves included in the first marking portion M1 and the grooves included in the second marking portion are not formed. In the case of a continuous part, the laser irradiation or cutting must be stopped every time. Therefore, when laser processing or cutting processing is used to process the hose 22A, the work is complicated.

In addition, if a groove is formed on the outer peripheral surface of the hose 22A by laser processing or cutting processing, the thickness of the portion where the groove is formed becomes thinner, which reduces the mechanical strength. If the thickness of the hose is increased in order to ensure the strength of the part where the groove is formed by laser processing or cutting, it will impair flexibility and increase the diameter of the hose.

In this regard, in the method of manufacturing the inner tube of this embodiment, the marking portion is formed by hot pressing. Therefore, by adjusting the design of the first mold MD1 and the second mold MD2, and the relative positions of the first mold MD1 and the second mold MD2, the groove included in the first indicator portion M1 can be compared with the groove included in the second indicator portion. The discontinuous part is easily formed with high reproducibility.

In addition, during the hot pressing, the inner peripheral surface side protrudes in response to the stress from the outer peripheral surface of the hose 22A, and a convex portion is formed on the inner peripheral surface of the hose 22A. Therefore, the inner tube manufactured by hot pressing has less wall thickness than the inner tube manufactured by laser processing or cutting.

With regard to the method of manufacturing the inner tube of this embodiment, the core 30 is inserted through the hose 22A before hot pressing. The core 30 supports the hose 22A from the inner peripheral side during hot pressing, so that press processing can be easily performed.

In addition, the diameter of the core 30 is larger than the diameter of the guide cable GW used in the catheter 1A. Therefore, it is possible to reliably insert the guide cable GW into the obtained inner tube 22, and it is possible to suppress the occurrence of defective products in which the guide cable cannot be inserted. As above, the required inner tube can be manufactured.

According to the inner tube with the above-mentioned configuration, when the catheter is used, the position in the body can be detected by irradiating ultrasonic waves, and it is not easily damaged. In addition, the catheter with the above-mentioned configuration can detect the position in the body by ultrasonic irradiation and is not easily damaged. In addition, according to the method for manufacturing the inner tube having the above-mentioned configuration, the inner tube can be easily manufactured.

In addition, the pattern of the marking portion formed on the outer peripheral surface of the inner tube is not limited to the aforementioned configuration.

For example, in this embodiment, as shown in FIG. 5, the groove 221 is formed in the circumferential direction of the outer peripheral surface of the inner tube 22 so as to be orthogonal to the central axis L in the field of view of FIG. 4. However, it is not limited to this .

Fig. 10 is a schematic diagram showing a modification of the inner tube and corresponds to Fig. 4. Like the inner tube 24 shown in FIG. 10, the groove 241 formed on the outer peripheral surface may be provided so as to diagonally cross the central axis L in the visual field of FIG. In this case, the groove 241 will form an arc on the outer peripheral surface of the inner tube 24.

In addition, in this embodiment, as shown in FIG. 5, the pattern formed by the plurality of grooves 221a included in the first indicator portion M1 and the pattern formed by the plurality of grooves 221b included in the second indicator portion M2 , Departments are consistent with each other, but they can be different from each other.

FIG. 11 is a schematic diagram showing a modification of the inner tube, and is a diagram corresponding to FIG. 5. Like the inner tube 25 shown in FIG. 11, the interval of the plurality of grooves 252 formed in the second indicator portion M2 is different from the interval of the plurality of grooves 251 formed in the first indicator portion M1, thereby making the pattern Different. In this case, as indicated by the symbols P3 and P4, the interval of the plurality of grooves 252 formed in the second indicator portion M2 may be wider with respect to the interval of the plurality of grooves 251 formed in the first indicator portion M1. In addition, as indicated by the symbols P5 and P6, the interval of the plurality of grooves 252 formed in the second indicator portion M2 may be narrower with respect to the interval of the plurality of grooves 251 formed in the first indicator portion M1.

In addition, the size of the groove 253 formed in the second indicator portion M2 may be different from the groove 251 formed in the first indicator portion M1, thereby making the pattern different.

In addition, the groove of the first indicator portion M1 is made orthogonal to the central axis L in the field of view orthogonal to the central axis L as shown in FIG. 5, and the groove of the second indicator portion M2 is made as shown in FIG. It may cross the central axis L diagonally in this field of view.

In this way, by making the forms of the first marking part M1 and the second marking part M2 different, the display mode of the echo image corresponding to the posture of the marking part M will also be changed. Therefore, it can be easily distinguished from noise in the echo image, and the operability is improved.

In addition, in the present embodiment, the indicator portion M has a first area AR1 and a second area AR2, but it is not limited to this, and further has a third area whose interval between the grooves 221 is different from the first area AR1 and the second area AR2 It may also have a multi-region configuration.

Furthermore, in this embodiment, the indicator portion M has a groove, but the structure of the indicator portion is not limited to the groove. As a structure to diffuse ultrasonic waves, the indicator portion may have a plurality of protrusions or roughened areas. Such protrusions or roughened areas can also be easily formed by hot pressing.

[Second Embodiment] Figures 12 and 13 are explanatory diagrams of the inner tube and the catheter in the second embodiment of the present invention. The inner tube and catheter of this embodiment are partly common with the inner tube and catheter of the first embodiment. Therefore, the same reference numerals are assigned to the constituent elements in this embodiment that are common to the first embodiment, and detailed descriptions are omitted.

FIG. 12 is a schematic cross-sectional view of the catheter hose 5 having the catheter 1B of this embodiment, and corresponds to FIG. 2. As shown in FIG. 2, the catheter hose 5 has an outer tube 51 and an inner tube 52 inserted into the outer tube 51. The outer tube 51 and the inner tube 52 form a double tube structure.

The material for forming the outer tube 51 can be the same as the material for forming the outer tube 21 described above.

Inside the outer tube 51, a partition wall 519 is provided along the longitudinal direction of the outer tube 51. The inner space of the outer tube 51 is divided by the partition wall 519 into a space 51a through which the guide cable GW is inserted, and a space 51b in which an expansion fluid that expands a balloon (not shown) flows. The space 51a and the space 51b are both formed along the length direction of the outer tube 51.

The outer peripheral surface of the end 52a of the inner tube 52 on the connector side is an inner wall 51x fixed to the end of the outer tube 51 on the airbag side by welding.

Since the inner peripheral surfaces of the outer tube 51 and the inner tube 52 slide with the guide cable GW, it is preferable to be coated with a low-friction material such as silicone resin and fluororesin.

The outer peripheral surface of the outer tube 51 may be coated with a hydrophilic resin such as polyvinylpyrrolidone and 2-hydroxyethyl methacrylate.

FIG. 13 is a schematic cross-sectional view showing the peripheral structure of the airbag 3 and corresponds to FIG. 3.

On the outer circumferential surface of the inner tube 52 and overlap with the conical portion 3b of the airbag 3, a marking portion M is provided. A plurality of grooves 221 are provided in the marking portion M. In addition, the marking portion M of the inner tube 52 shown in FIG. 13 may not be provided on the outer circumferential surface of the inner tube 52 and overlapped with the cylindrical portion 3a of the airbag 3.

The balloon 3 before expansion is wound around the inner tube 52. Here, the cylindrical portion 3a of the airbag 3 has a larger diameter D than the conical portion 3b, and when compared in the circumferential direction, the amount of resin constituting the cylindrical portion 3a is greater than the amount of resin constituting the conical portion 3b. Therefore, the airbag 3 wound around the inner tube 52 is wound thicker around the cylindrical part 3a than the conical part 3b.

Therefore, in the ultrasonic waveguide PTA, the ultrasonic wave irradiated to the position overlapping the cylindrical portion 3a is likely to be attenuated by the resin constituting the cylindrical portion 3a wound around the inner tube 52. Therefore, in the echo image using ultrasonic waves, even if the marking part M is provided at the position overlapping the cylindrical part 3a, it is difficult to detect the marking part M.

In contrast, the ultrasonic waves irradiated to the position overlapping the cone portion 3b are easily attenuated by the resin constituting the cone portion 3b wound around the inner tube 52, but are less likely to be attenuated than the ultrasonic waves irradiated to the cylindrical portion 3a . Therefore, in the echo image using ultrasonic waves, it is easier to detect the marking part M provided at the position overlapping the cone part 3b than when the marking part is arranged at the position overlapping the cylindrical part 3a.

Thereby, as shown in FIG. 13, since the cone portion 3b is provided with the marking portion M, even if the balloon 3 before expansion is wound around the inner tube 52, the marking portion M can be properly detected in the echo image, and The position of the airbag 3 can be easily detected.

According to the inner tube with the above-mentioned configuration, even when the catheter is used, the position in the body can be detected by irradiating ultrasonic waves, and it is not easily damaged. In addition, according to the catheter having the inner tube as described above, the position in the body can be detected by ultrasonic irradiation without being easily damaged.

[Third Embodiment] 14 and 15 are explanatory diagrams of the inner tube and catheter in the third embodiment of the present invention. The inner tube and catheter of this embodiment are partly common with the inner tube and catheter of the first and second embodiments. Therefore, the same reference numerals are assigned to the constituent elements described in the present embodiment, and detailed descriptions are omitted.

Fig. 14 is a schematic cross-sectional view showing the peripheral structure of the balloon 3 of the catheter 1C, and corresponds to Figs. 3 and 13.

On the tip side of the catheter 1C, the inner tube 56 is exposed between the cutter 29 and the balloon 3. In Fig. 14, the portion (exposed portion) of the inner tube 56 that does not overlap with the airbag is indicated by the symbol α.

A marking part M is provided on the exposed part α. The marking portion M shown in FIG. 14 is provided from the conical portion 3b to the exposed portion α.

Fig. 15 is a schematic enlarged view of the part indicated by the symbol X in Fig. 14. The outer tube 55 is attached to the outer peripheral surface of the outer tube 51 shown in the second embodiment, and is provided with an outer tube indicator portion OM that reduces the amount of regular reflection of ultrasonic waves relative to other parts of the outer peripheral surface of the outer tube 55. A plurality of grooves 551 are provided in the outer tube marking part OM. The outer tube marking part OM is arranged at a position adjacent to the airbag 3. The term "adjacent" means that the separation distance from the end of the airbag 3 to the groove 551 on the airbag 3 side of the outer tube indicator portion OM is 0 mm or more and 10 mm or less.

The groove 551 can be formed by the same method as the marking portion M included in the inner tube 22 of the first embodiment.

The depth of the groove 551 is, for example, 50 μm to 300 μm. In addition, the width of the groove 551 is, for example, 50 μm to 300 μm. The edge of the groove 551 may be convex. When the edge of the groove 551 is raised in a convex shape, the depth of the groove refers to the difference in height from the deepest part of the groove to the top of the convex part. In the case where the necessary strength of the outer tube 55 can be ensured and there are no manufacturing defects, the groove 551 is preferably deep.

In the outer tube marking portion OM, the ultrasonic wave is diffused by the groove 551, and the amount of regular reflection of the ultrasonic wave is relatively reduced compared to the portion where the groove 551 is not provided. Therefore, in the ultrasonic wave guide PTA, after the ultrasonic wave irradiated to the catheter is reflected, the amount of the ultrasonic wave reaching the probe receiving the reflected ultrasonic wave is reduced. Therefore, in the echo image using ultrasonic waves, the part corresponding to the groove 551 is displayed darkly, and the outer tube marking part OM displayed as a striped pattern is detected.

In addition, since the outer tube indicator portion OM does not overlap with the airbag 3, it is possible to prevent the irradiated ultrasonic wave from being attenuated by the airbag 3 and difficult to reach the outer tube indicator portion OM.

Thereby, by providing the marking part M and the outer tube marking part OM as shown in FIGS. 14 and 15, even if the balloon 3 before expansion is wound around the inner tube 56, the marking can be appropriately detected in the echo image. The part M and the outer tube mark the part OM, so that the position of the airbag 3 can be easily detected.

According to the inner tube with the above-mentioned configuration, even when the catheter is used, the position in the body can be detected by irradiating ultrasonic waves, and it is not easily damaged. In addition, according to the catheter having the inner tube as described above, the position in the body can be detected by ultrasonic irradiation without being easily damaged.

In addition, in the present embodiment, for the balloon 3, both the marking on the distal end side of the catheter 1C (marking part M) and the marking on the connector 4 side (outer tube marking part OM) are provided at positions that do not overlap with the balloon 3. However, it is not limited to this.

For example, the distal end side of the catheter 1C has the same configuration as the first embodiment or the second embodiment, and the marking portion M is provided at the position overlapping the balloon 3, and the connector 4 side is provided with a third The outer tube marking part OM shown in the embodiment may also be used.

In addition, on the tip side of the catheter 1C, a marking portion M is provided on the exposed portion α shown in the third embodiment, and on the connector 4 side, it is inside as shown in the first embodiment or the second embodiment. The tube may be provided with a marking part M.

In the above, suitable embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to these examples. The various shapes or combinations of the constituent members shown in the foregoing examples are just examples, and various changes can be made in accordance with design requirements and the like without departing from the spirit of the present invention.

1: Catheter 3: airbag 21: Outer tube 22, 23, 24, 25: inner tube 22A: hose 30: SMIC 221,221a,221b,241,251,252,253: groove 222, 222a, 222b, 232: convex part AR1: Area 1 AR2: Area 2 GW: Guide cable L: central axis M: marking part M1: The first marking part M2: 2nd marking part MD1: The first mold MD2: 2nd mold P1~P6: interval X1, X2: end

Fig. 1 is a schematic diagram showing a catheter 1A of the first embodiment. [Fig. 2] A schematic cross-sectional view of the catheter hose 2. Fig. 3 is a schematic cross-sectional view showing the peripheral structure of the airbag 3. [Fig. 4] A plan view of the inner tube 22. [Fig. [Fig. 5] A side view of the inner tube 22. [Fig. 6] A cross-sectional view of the inner tube 22. [Fig. 7] A cross-sectional view of the inner tube 22. [Fig. 8] A sectional view of the inner tube 23. Fig. 9 is a schematic diagram showing a method of manufacturing an inner tube. Fig. 10 is a schematic diagram showing a modification of the inner tube. Fig. 11 is a schematic diagram showing a modification of the inner tube. Fig. 12 is a schematic cross-sectional view of a catheter hose 5 having a catheter 1B of the second embodiment. [Fig. 13] A schematic cross-sectional view showing the peripheral structure of the airbag 3. Fig. 14 is a schematic cross-sectional view showing the peripheral structure of the balloon 3 of the catheter 1C of the third embodiment. [FIG. 15] It is a schematic enlarged view of the part shown by the symbol X in FIG. 14. [FIG.

221, 221a, 221b: groove

L: central axis

M1: The first marking part

M2: The second marking part

P1, P2: interval

X1, X2: end

Claims (15)

An inner tube used for medical catheters; its characteristics are: On the outer circumferential surface of the inner tube, there is provided a marking portion that makes the amount of regular reflection of the ultrasonic wave relatively smaller than other parts of the outer circumferential surface, The aforementioned indicator portion includes: a first indicator portion, which is a half-peripheral surface on one side of the outer peripheral surface; and a second indicator portion, which is provided on a half-peripheral surface on the other side of the outer peripheral surface, The indicator portion has a plurality of arc-shaped grooves extending around the central axis of the inner tube, and includes: the grooves included in the first indicator portion and the grooves included in the second indicator portion are discontinuous section. The inner tube as described in claim 1, in which, On the inner peripheral surface of the inner tube, there is provided a ridge portion overlapping the groove in a visual field viewed from a direction perpendicular to the central axis along the groove, The said convex line part overlapping with the said groove of the said 1st indication part and the said convex line part overlapping with the said groove of the said 2nd indication part are not continuous. The inner tube as described in claim 2, in which, The protruding stripe portion on the inner peripheral surface side of the first indicator portion and the protruding stripe portion on the inner peripheral surface side of the second indicator portion are in a field of view viewed from a direction orthogonal to the central axis of the inner tube Does not overlap. The inner tube according to any one of claims 1 to 3, wherein: The indicator portion has: a first area in which the plurality of grooves are close to each other; and a second area in which the interval between the plurality of grooves is wider than that of the first area. The inner tube according to any one of claims 1 to 4, wherein: The groove extends in the circumferential direction of the outer peripheral surface. The inner tube according to any one of claims 1 to 5, wherein: The pattern formed by the plurality of grooves included in the first indicator portion and the pattern formed by the plurality of grooves included in the second indicator portion are consistent with each other. The inner tube according to any one of claims 1 to 5, wherein: The pattern formed by the plurality of grooves included in the first indicator portion and the pattern formed by the plurality of grooves included in the second indicator portion are different from each other. A catheter system having: The inner tube described in any one of claims 1 to 7; The outer tube is inserted with the aforementioned inner tube; and The airbag is attached to the end of the aforementioned outer tube; The aforementioned inner tube has the aforementioned indicator portion at a portion overlapping with the aforementioned airbag. A catheter system having: The inner tube described in any one of claims 1 to 7; The outer tube is inserted with the aforementioned inner tube; and The airbag is attached to the end of the aforementioned outer tube; The aforementioned airbag has: a cylindrical portion; and a pair of cone portions, which are arranged on both sides of the aforementioned cylindrical portion; The inner tube has the indicator portion at a position overlapping the pair of cone portions. A catheter system having: The inner tube described in any one of claims 1 to 7; The outer tube is inserted with the aforementioned inner tube; and The airbag is attached to the end of the aforementioned outer tube; The aforementioned airbag has: a cylindrical portion; and a pair of cone portions, which are arranged on both sides of the aforementioned cylindrical portion; The inner tube has the indicator portion at a position overlapping with the cone portion on the tip side of the inner tube, On the outer peripheral surface of the outer tube, there is provided an outer tube marking portion that reduces the amount of regular reflection of the ultrasonic wave relative to other parts of the outer peripheral surface of the outer tube, The outer tube marking part is arranged at a position adjacent to the airbag. The catheter according to claim 9 or 10, wherein: The inner tube has the indicator portion at a position that does not overlap with the airbag. The catheter according to any one of claims 9 to 11, wherein: The inner tube has the indicator part at a position that does not overlap the cylindrical part. The catheter according to any one of claims 8 to 12, wherein: It has: a guide cable which is inserted into the aforementioned inner tube. A method for manufacturing an inner tube, which is the method for manufacturing an inner tube according to any one of claims 1 to 7, characterized in that: Using a first mold having irregularities that are complementary to the first indicator portion, and a second mold that has irregularities that are complementary to the second indicator portion, the outer peripheral surface of the resin hose is formed by hot pressing. Steps in the plural grooves of the first marking part and the second marking part. The method of manufacturing an inner tube according to claim 14, wherein: There is a step of inserting a metal core into the hose before the step of forming the groove.

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