Puncture device

Abstract

To provide a puncture device that has high puncture property and safety property.SOLUTION: A puncture device 1 includes: a puncture part 11 including a needle tip with a sharp tip; and a shaft part 12 provided on a proximal end side of the puncture part 11. The shaft part 12 includes: a core material 121; and an outside layer body 122 disposed at an outer peripheral surface of the core material 121.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a puncture device for an endoscope.

Background Art

[0002] Conventionally, a technique called Interventional EUS is known, in which the abdominal cavity is observed with an endoscopic ultrasound (EUS) via the digestive tract such as the stomach or intestine, and treatment is performed on diseases in the abdominal cavity. As one such technique, there is endoscopic ultrasound-guided biliary drainage (EUS-BD) in which the bile duct is punctured from inside the stomach or duodenum and a stent is placed in the bile duct with poor bile flow. For example, in the case of a procedure for puncturing the bile duct from inside the stomach called EUS-HGS, an endoscopic puncture device equipped with a sheath and a puncture needle is used together with an endoscopic ultrasound. In EUS-HGS, the tip of the puncture needle is pushed out from the tip of the sheath protruding from the tip of the endoscopic ultrasound, and the stomach and liver are punctured so as to reach the intrahepatic bile duct from the inside of the stomach, and a fistula is formed from the stomach to the bile duct. For example, Patent Document 1 discloses an endoscopic puncture device used for such a procedure.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The endoscopic puncture device described in Patent Document 1 has a flexible sheath inserted into the inside of an ultrasound endoscope (instrument insertion channel), through which a puncture needle made of a thin-walled stainless steel pipe or other metal pipe material is inserted. When performing a puncture procedure using such an endoscopic puncture device, the puncture site is often punctured with the endoscope at a sufficient upward angle (i.e., with the tip of the endoscope bent) in order to stabilize the tip of the endoscope. However, when the puncture needle is pushed out with the endoscope at an angle, the puncture needle itself may develop a bend and deform. When the puncture needle bends, it loses its straight-line stability, which makes it difficult to aim at the puncture site.

[0005] This invention has been made in view of these points, and aims to provide a puncture device that has high puncture efficiency and safety. [Means for solving the problem]

[0006] To achieve the above objective, the present invention provides a puncture device comprising a puncture portion having a sharp needle tip and a shaft portion provided on the proximal end side of the puncture portion, wherein the shaft portion comprises a core material and an outer layer body disposed on the outer circumferential surface of the core material (Invention 1).

[0007] According to this invention (Invention 1), by arranging an outer layer on the outer surface of the core material, the flexibility of the shaft can be easily adjusted by changing the diameter of the core material and the thickness of the outer layer. As a result, the shaft can be made more flexible than the puncture portion, and a puncture device with high puncture performance and safety can be provided.

[0008] Furthermore, by arranging the outer layer on the outer surface of the core material, the outer diameter of the puncture portion and the outer diameter of the shaft can be made uniform by varying the diameter of the core material and the thickness of the outer layer. As a result, when the puncture portion and shaft are positioned inside the inner sheath, there is no unnecessary clearance (gap) between the outer surfaces of the puncture portion and shaft and the inner surface of the inner sheath, so that when puncture is performed using the puncture device, it is possible to suppress unnecessary movements such as bending of the shaft inside the inner sheath.

[0009] In the above invention (Invention 1), the tip of the core material may be located inside the puncture portion (Invention 2).

[0010] According to this invention (Invention 2), the puncture portion and the shaft portion can be joined more stably than simply bringing them into contact and joining them with a surface.

[0011] In the above invention (Invention 2), the tip of the core material may be inserted into the insertion hole formed in the puncture portion (Invention 3).

[0012] In the above invention (Invention 1), the rear end of the puncture portion and the front end of the outer layer body may be in contact (Invention 4).

[0013] In the above invention (Invention 1), the outer diameter of the puncture portion and the outer diameter of the shaft portion may be substantially the same (Invention 5). [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a puncture device that combines high puncture performance and safety. [Brief explanation of the drawing]

[0015] [Figure 1] This is an explanatory diagram showing the overall structure of the puncture device according to the first embodiment. [Figure 2] This is an explanatory diagram showing the structure of the tip of the puncture device according to the first embodiment. [Figure 3]This is an explanatory diagram showing the structure of the tip of the puncture device according to the second embodiment. [Figure 4] This is an explanatory diagram showing the structure of the tip of the puncture device according to the third embodiment. [Modes for carrying out the invention]

[0016] Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the present invention is not limited to the embodiments described below, and the described embodiments are merely examples to illustrate the technical features of the present invention. Furthermore, the shapes and dimensions shown in each drawing are provided solely to facilitate understanding of the present invention and do not accurately reflect the actual shapes and dimensions.

[0017] <First Embodiment> Figure 1 is an explanatory diagram showing the overall structure of the puncture device 1 according to the first embodiment, and Figure 2 is an explanatory diagram showing the structure of the tip portion of the puncture device 1 (the portion enclosed by the dashed line in Figure 1).

[0018] In this specification, "tip side" means the direction along the axial direction of the puncture device 1, in which the puncture device 1 and the endoscope (not shown) to which it is attached advance toward the puncture site. "Proximal side" means the direction along the axial direction of the puncture device 1, in the opposite direction to the tip side. Furthermore, "tip" refers to the tip end of any member or part, and "proximal end" refers to the proximal end of any member or part. In addition, "tip portion" refers to the portion of any member or part that includes the tip and extends from the tip toward the proximal end to the middle of the member, etc., and "proximal end portion" refers to the portion of any member or part that includes the proximal end and extends from this proximal end toward the tip to the middle of the member, etc. In Figure 1, the left side of the figure is the "tip side" that is inserted into the body, and the right side of the figure is the "proximal side" that is manipulated by the operator.

[0019] As shown in FIG. 1, the puncture device 1 includes a needle member 10, an inner sheath 20, an outer sheath 30, and an operation unit 40. The puncture device 1 is used, for example, in the procedure of EUS-BD, to penetrate the tip of the needle member 10 through the peripheral wall of a luminal organ (such as the stomach or liver) to be bypass-connected to form a puncture hole, and to insert a guide wire between the luminal organs through the puncture hole. The puncture device 1 is configured such that the outer sheath 30 (and the inner sheath 20 and the needle member 10 incorporated in the lumen of the outer sheath 30) is inserted into a treatment tool insertion channel of an endoscope not shown, and by operating the operation unit 40, the outer sheath 30 is slidable (relatively movable) in the axial direction with respect to the treatment tool insertion channel of the endoscope. The tip of the puncture device 1 protrudes from the tip of the treatment tool insertion channel of the endoscope.

[0020] The inner sheath 20 is a flexible and elongated tubular member, and the needle member 10 is inserted into its lumen. The inner diameter of the inner sheath 20 is formed to be equal to or slightly larger than the outer diameter of the needle member 10 so that the needle member 10 can slide (relatively move) axially within the lumen of the inner sheath 20. Also, the outer diameter of the inner sheath 20 is formed to be slightly smaller than the inner diameter of the outer sheath 30 so that the inner sheath 20 can slide (relatively move) axially within the lumen of the outer sheath 30 described later.

[0021] The material forming the inner sheath 20 is not particularly limited as long as it has a strength capable of withstanding the sliding of the needle member 10 within its lumen and has biocompatibility. For example, various resin materials such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, acrylic resin, phenolic resin, melamine resin, polyimide, polyamide, polycarbonate, polyethersulfone, polyetheretherketone, polytetrafluoroethylene, etc., and various thermoplastic elastomers such as polystyrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polybutadiene-based, etc. can be used. Two or more of these can also be used in combination.

[0022] The inner sheath 20 is axially slidable (relatively movable) with respect to the outer sheath 30 by operating the operation unit 40.

[0023] The outer sheath 30 is an elongated tubular member having flexibility, and the inner sheath 20 is inserted into its lumen. The inner diameter of the outer sheath 30 is formed slightly larger than the outer diameter of the inner sheath 20 so that the inner sheath 20 can slide axially (relatively move) within the lumen of the outer sheath 30. The outer diameter of the outer sheath 30 is sized to be insertable into a treatment tool insertion channel of an endoscope (not shown).

[0024] The material forming the outer sheath 30 is not particularly limited as long as it has a strength capable of withstanding the sliding of the inner sheath 20 within its lumen and has biocompatibility. For example, the materials exemplified as the materials forming the above inner sheath 20 can be used.

[0025] The outer sheath 30 is axially slidable (relatively movable) with respect to the treatment tool insertion channel of the endoscope by operating the operation unit 40.

[0026] The operation unit 40 is composed of, for example, a plurality of members formed of a resin material, and includes an operation unit main body 41 to which the proximal end portion of the outer sheath 30 is fixed, and a slider portion 42 slidably provided with respect to the operation unit main body 41. Each member constituting the operation unit 40 may all be formed of the same material or may be partially formed of different materials.

[0027] The operation unit main body 41 generally has an elongated cylindrical shape, and includes a connection portion 411 connected and fixed to the entrance of the treatment tool insertion channel of the endoscope, an outer sheath length adjustment portion 412 connected to the proximal end side of the connection portion 411, and an inner sheath length adjustment portion 413 connected to the proximal end side of the outer sheath length adjustment portion 412.

[0028] The connecting portion 411 is fixed to the tip of the scale portion 4121 of the outer sheath length adjustment portion 412 by means of adhesive or other means, and the base end of the outer sheath 30 is fixed to it. The connecting portion 411 is connected and fixed to the entrance of the instrument insertion channel of the endoscope, thereby making it possible to fix the puncture device 1 to the endoscope.

[0029] The outer sheath length adjustment section 412 is a mechanism for adjusting the positional relationship between the endoscope and the outer sheath 30, and has a scale section 4121 and a stopper 4122. The stopper 4122 is slidably positioned relative to the scale section 4121. The scale section 4121 has multiple scales that serve as indicators for setting the position of the stopper 4122, and each scale is arranged at a predetermined interval on the outer surface of the scale section 4121. Each scale represents the length from the tip of the connecting section 411 to the tip of the outer sheath 30.

[0030] The inner sheath length adjustment section 413 is a mechanism for adjusting the positional relationship between the outer sheath 30 and the inner sheath 20 (and the needle member 10 incorporated within the lumen of the inner sheath 20), and has a scale section 4131 and a stopper 4132. The stopper 4132 is slidably positioned relative to the scale section 4131. The scale section 4131 has multiple scales that serve as indicators for setting the position of the stopper 4132, and each scale is arranged at a predetermined interval on the outer circumferential surface of the scale section 4131. Each scale represents the protruding length of the inner sheath 20 (and the needle member 10 incorporated within the lumen of the inner sheath 20) from the tip of the outer sheath 30. For example, the stopper 4132 is positioned at the scale position corresponding to the numerical value "1" and fixed by turning a screw. In this state, sliding the slider part 42 toward the tip allows the tip of the inner sheath 20 (and needle member 10) to protrude from the tip of the outer sheath 30 by the length indicated by the scale (1 cm).

[0031] The slider portion 42 has an overall elongated cylindrical shape and includes a handle portion 421 that is gripped by the user and a needle fixing portion 422 connected to the base end of the handle portion 421, to which the base end of the needle member 10 is fixed.

[0032] As shown in Figure 2, the needle member 10 according to this embodiment comprises a solid puncture portion 11 having a sharp needle tip 111 and a shaft portion 12 provided on the base end side of the puncture portion 11. The length of the puncture portion 11 is approximately 5 to 80 mm, and the length of the shaft portion 12 varies depending on the application of the puncture device 1.

[0033] The puncture portion 11 comprises a needle tip 111 which is roughly triangular pyramidal in shape with a triangular pointed tip, and a cylindrical base 112 which is integrally formed with the needle tip 111. An insertion hole 113 is drilled at the base end of the base 112, opening in the direction toward the shaft portion 12 (base end direction).

[0034] The material used to form the puncture site 11 is not particularly limited, as long as it has sufficient hardness and strength to allow the needle tip 111 to penetrate the target site and form a puncture hole, and is biocompatible. For example, metallic materials such as stainless steel, titanium, nickel-titanium alloy, and cobalt-chromium alloy can be used.

[0035] The maximum outer diameter of the needle tip 111 of the puncture portion 11 must be the same as or smaller than the outer diameter of the base portion 112 so that the puncture portion 11 does not get caught on the inner sheath 20 when the needle member 10 is withdrawn from the inner sheath 20.

[0036] The shaft portion 12 comprises a core material 121 having a diameter that is substantially uniform along its entire length and a substantially circular cross-section, and an outer layer body 122 disposed on the outer circumferential surface of the core material 121. The outer diameter of the outer layer body 122 is substantially the same as the outer diameter of the base portion 112 of the puncture portion 11, and the needle member 10 is inserted into the lumen of the inner sheath 20 such that the outer circumferential surface from the base portion 12 of the puncture portion 11 to the entire outer layer body 122 is in contact with the inner circumferential surface of the inner sheath 20.

[0037] The tip portion 1211 of the core material 121 is inserted into an insertion hole 113 formed in the base portion 112 of the puncture portion 11. This ensures that at least a portion of the core material 121 (the tip portion 1211) is located inside the puncture portion 11. The tip portion 1211 of the core material 121 may be fixed to the base portion 112 of the puncture portion 11 using known fixing means. The material forming the core material 121 is not particularly limited, but for example, the same metal material as the material forming the puncture portion 11 can be used. The core material 121 may be formed entirely of the same material, or it may be formed partially of different materials. By configuring the needle member 10 so that at least a portion of the core material 121 (the tip portion 1211) is located inside the puncture portion 11, the two can be joined more stably than simply bringing the puncture portion 11 and the shaft portion 12 into contact and joining them at a surface.

[0038] The outer layer 122 of the shaft portion 12 is a wire rope formed by twisting multiple wires (straight strands or groups of strands) in a spiral shape and arranging them around the core material 121. The material forming the outer layer 121 is not particularly limited, but for example, the same metal material as the material forming the puncture portion 11 can be used. The outer layer 121 may be made entirely of the same material, or it may be made partially of different materials. By using a wire rope as the outer layer 122, the outer surface of the shaft portion 12 can be made uneven, and as a result the contact area with the inner circumferential surface of the inner sheath 20 is reduced, improving the sliding performance of the needle member 10.

[0039] The tip of the outer layer 122 (the tip surface of the outer layer 122) is in contact with the base end of the puncture portion 11 (the base end surface of the base portion 112 of the puncture portion 11), and the base end of the puncture portion 11 and the tip of the outer layer 122 are fixed together using known joining methods such as adhesive, brazing, pressure welding, or YAG laser welding.

[0040] As described above, if the outer layer 122 is arranged on the outer circumferential surface of the core material 121, the flexibility of the shaft portion 12 can be easily adjusted by changing the diameter of the core material 121 and the thickness of the outer layer 122. As a result, the shaft portion 12 can be made more flexible than the puncture portion 11, and a puncture device 1 with high puncture performance and safety can be provided.

[0041] Furthermore, by arranging the outer layer 122 on the outer circumferential surface of the core material 121, the outer diameter of the puncture portion 11 and the outer diameter of the shaft portion 12 can be made uniform (i.e., the outer diameter of the needle member 10 can be made uniform overall) by changing the diameter of the core material 121 and the thickness of the outer layer 122. As a result, when the needle member 10 (puncture portion 11 and shaft portion 12) is arranged inside the inner sheath 20, there is no unnecessary clearance (gap) between the outer circumference of the needle member 10 (puncture portion 11 and shaft portion 12) and the inner circumferential surface of the inner sheath, so that when puncturing with the puncture device 1, it is possible to suppress unnecessary movements such as bending of the shaft portion 12 inside the inner sheath 20.

[0042] Furthermore, if the shaft portion 12 is formed to be more flexible than the puncture portion 11, when performing a puncture procedure using the puncture device 1, even if the needle member 10 is pushed out with the endoscope at an upward angle, it is possible to suppress the deformation of the needle member 10 itself by preventing it from bending. This allows for a complete and smooth perforation at the puncture target site, providing a puncture device 1 with high puncture performance and safety.

[0043] <Second Embodiment> The puncture device 1A according to the second embodiment is modified so that the needle member 10 of the puncture device 1 according to the first embodiment is replaced with a needle member 10A having the structure described below. The structure of the inner sheath 20, outer sheath 30, and operating section 40 is the same as that of the puncture device 1 according to the first embodiment, so their description is omitted.

[0044] Figure 3 is an explanatory diagram showing the structure of the tip of the puncture device 1A according to the second embodiment. As shown in Figure 3, the needle member 10A according to this embodiment comprises a solid puncture portion 11A having a sharp needle tip 111 and a shaft portion 12A provided on the base end side of the puncture portion 11A. The length of the puncture portion 11A is approximately 5 to 80 mm, and the length of the shaft portion 12A varies depending on the application of the puncture device 1.

[0045] The puncture portion 11A comprises a needle tip 111A which is roughly triangular pyramidal in shape with a triangular pointed tip, and a cylindrical base portion 112A which is integrally formed with the needle tip 111A. An insertion hole 113A is drilled at the base end side of the base portion 112A, opening in the direction toward the shaft portion 12A (base end direction).

[0046] The material used to form the puncture site 11A is not particularly limited, as long as it has sufficient hardness and strength to allow the needle tip 111A to penetrate the puncture site and form a puncture hole, and is biocompatible. For example, metallic materials such as stainless steel, titanium, nickel-titanium alloy, and cobalt-chromium alloy can be used.

[0047] The shaft portion 12A comprises a core material 121A having a roughly circular cross-section, where the diameter of the core tip portion 1213A is smaller than that of the core body portion 1211A, and an outer layer body 122A disposed on the outer circumferential surface of the core material 121A. The outer diameter of the outer layer body 122A is approximately the same as the outer diameter of the puncture portion 11A, and the needle member 10A is inserted into the lumen of the inner sheath 20 such that the outer circumferential surface from the puncture portion 11A to the outer layer body 122A is in contact with the inner circumferential surface of the inner sheath 20.

[0048] The core material 121A comprises a core body portion 1211A with a substantially cylindrical shape, a core tapered portion 1212A having a tapered shape (frustoconical shape) with a gradually decreasing outer diameter, and a core tip portion 1213A with a substantially cylindrical shape having a smaller outer diameter than the core body portion 1211A. The outer diameter of the core body portion 1211A is equal to the inner diameter of the outer layer 122A, and the outer diameter of the core tip portion 1213A is formed to be equal to the inner diameter of the insertion hole 113A of the puncture portion 11A.

[0049] The tip portion 1213A of the core material 121A is inserted into the insertion hole 113A of the puncture portion 11A. This ensures that at least a portion of the core material 121A (the tip portion 1211A) is located inside the puncture portion 11A. The tip portion 1213A of the core material 121A may be fixed to the puncture portion 11A using known fixing means. The material forming the core material 121A is not particularly limited, but for example, the same metal material as the material forming the puncture portion 11A can be used. The core material 121A may be formed entirely of the same material, or it may be formed partially of different materials.

[0050] The outer layer 122A of the shaft portion 12A is a wire rope formed by twisting multiple wires (straight strands or groups of strands) in a spiral shape and arranging them around the core material 121A. The material forming the outer layer 121A is not particularly limited, but for example, the same metal material as the material forming the puncture portion 11A can be used. The outer layer 121A may be formed entirely of the same material, or it may be formed partially of different materials.

[0051] The tip of the outer layer 122A is in contact with the base end of the puncture portion 11A, and the base end of the puncture portion 11A and the tip of the outer layer 122A are fixed together using known joining methods such as adhesive, brazing, pressure welding, or YAG laser welding.

[0052] As shown in the shaft portion 12A of this embodiment, by making the diameter of only the tip of the core material smaller compared to the overall diameter and forming a thinner outer layer, it becomes possible to use a core material with a larger diameter in the shaft portion while maintaining the overall outer diameter of the shaft portion, thereby increasing the degree of freedom in adjusting the flexibility of the shaft portion.

[0053] <Third Embodiment> The puncture device 1B according to the third embodiment is modified so that the needle member 10 of the puncture device 1 according to the first embodiment is replaced with a needle member 10B having the structure described below. The structure of the inner sheath 20, outer sheath 30, and operating section 40 is the same as that of the puncture device 1 according to the first embodiment, so their description is omitted.

[0054] Figure 4 is an explanatory diagram showing the structure of the tip of the puncture device 1B according to the third embodiment. As shown in Figure 3, the needle member 10B according to this embodiment comprises a hollow puncture portion 11B and a shaft portion 12B provided on the base end side of the puncture portion 11B. The length of the puncture portion 11B is approximately 5 to 80 mm, and the length of the shaft portion 12B varies depending on the application of the puncture device 1.

[0055] The puncture portion 11B has a shape in which a blade surface 115 is formed by cutting the tip side of a substantially cylindrical member, which has a through hole 114 with a cross-sectional shape that is normally circular in appearance along the axis, at an angle to the axis.

[0056] The material used to form the puncture site 11B is not particularly limited, as long as it has sufficient hardness and strength to allow the blade surface 115 to penetrate the puncture site and form a puncture hole, and is biocompatible. For example, metal materials such as stainless steel, titanium, nickel-titanium alloy, and cobalt-chromium alloy can be used.

[0057] The shaft portion 12B comprises a core material 121B having a roughly circular cross-section, where the diameter of the core tip portion 1213B is smaller than that of the core body portion 1211B, and an outer layer body 122B disposed on the outer circumferential surface of the core material 121B. The outer diameter of the outer layer body 122B is approximately the same as the outer diameter of the puncture portion 11B, and the needle member 10B is inserted into the lumen of the inner sheath 20 such that the outer circumferential surface from the puncture portion 11B to the outer layer body 122B is in contact with the inner circumferential surface of the inner sheath 20.

[0058] The core material 121B comprises a core body portion 1211B with a roughly cylindrical shape, a core tapered portion 1212B having a tapered shape (frustoconical shape) with a gradually decreasing outer diameter, and a core tip portion 1213B with a roughly cylindrical shape having a smaller outer diameter than the core body portion 1211B. The outer diameter of the core body portion 1211B is equal to the inner diameter of the outer layer body 122B, and the outer diameter of the core tip portion 1213B is equal to the inner diameter of the through hole 114 of the puncture portion 11B.

[0059] The tip portion 1213B of the core material 121B is inserted into the through hole 114 of the puncture portion 11B. This ensures that at least a portion of the core material 121B (the tip portion 1211B) is located inside the puncture portion 11B. The tip portion 1213B of the core material 121B may be fixed to the puncture portion 11B using known fixing means. The material forming the core material 121B is not particularly limited, but for example, the same metal material as the material forming the puncture portion 11B can be used. The core material 121B may be formed entirely of the same material, or it may be formed partially of different materials.

[0060] The outer layer 122B of the shaft portion 12B is a wire rope formed by twisting multiple wires (straight strands or groups of strands) in a spiral shape and arranging them around the core material 121B. The material forming the outer layer 121B is not particularly limited, but for example, the same metal material as the material forming the puncture portion 11B can be used. The outer layer 121B may be formed entirely of the same material, or it may be formed partially of different materials.

[0061] The tip of the outer layer 122B abuts against the base end of the puncture portion 11B, and the base end of the puncture portion 11B and the tip of the outer layer 122B are fixed together using known joining methods such as adhesive, brazing, pressure welding, or YAG laser welding.

[0062] As shown in the shaft portion 12B of this embodiment, by making the diameter of only the tip of the core material smaller compared to the overall diameter and forming a thinner outer layer, it becomes possible to use a core material with a larger diameter in the shaft portion while maintaining the overall outer diameter of the shaft portion, thereby increasing the degree of freedom in adjusting the flexibility of the shaft portion.

[0063] Furthermore, by providing a hollow puncture section with a through-hole formed along the axis, as in the puncture section 11B of this embodiment, it becomes possible to give the puncture section the function of a biopsy needle for collecting tissue samples from the puncture target site.

[0064] The puncture device according to the present invention has been described above with reference to the drawings, but the present invention is not limited to the above embodiments and various modifications are possible. For example, in the above embodiment, a wire rope formed by twisting multiple wires in a spiral shape is used for the outer layer 122 of the shaft portion 12, but the invention is not limited to this, and a tube or coil made of, for example, a metal material or a resin material may be used for the outer layer 122, taking into consideration the material used for the core material 121 of the shaft portion 12, so that the flexibility of the shaft portion 12 is greater than that of the puncture portion 11.

[0065] Furthermore, regarding the joining of the puncture portion 11 and the shaft portion 12, the joint strength may be increased by laser spot welding the tip portion 1211 of the core material 121, which is inserted into the insertion hole 113 of the puncture portion 11, from the outer surface of the puncture portion 11, or a groove may be cut into the outer surface of the puncture portion 11, and the tip portion 1211 of the core material 121 may be placed in the groove and embedded. [Explanation of Symbols]

[0066] 1, 1A, 1B Puncture Devices 10, 10A, 10B needle parts 11, 11A, 11B puncture site 111, 111A needle tip 112, 112A base 113, 113A Insertion holes 114 Through hole 115 Blade surface 12, 12A, 12B shaft part 121, 121A, 121B core material 122, 122A, 122B outer layer body 20 Inner sheath 30 Outer Sheath 40 Control section

Claims

1. A puncture unit having a sharp needle tip; A shaft portion provided on a proximal end side of the puncture portion, The shaft portion includes a core material and an outer layer disposed on an outer peripheral surface of the core material, The tip of the core material is inserted into an insertion hole formed in the puncture portion, A puncture device, wherein the outer diameter of the puncture portion is constant or decreases toward the tip.

2. A puncture device as described in claim 1, wherein the puncture portion has a constant outer diameter portion having a constant outer diameter, and a decreasing outer diameter portion provided on the tip side of the constant outer diameter portion and having an outer diameter that decreases toward the tip.

3. A puncture device as described in claim 1, wherein the puncture portion has a hollow structure.

4. A puncture device as described in claim 3, wherein the puncture portion has a blade surface formed by cutting the tip side diagonally with respect to the axis line.

5. The puncture device according to claim 1 , wherein a base end of the puncture portion and a tip end of the outer layer are in contact with each other.

6. The puncture device according to claim 1 , wherein an outer diameter of the puncture portion and an outer diameter of the shaft portion are substantially the same.

Images