Dilator

Abstract

The present invention provides a dilator that can maintain high torque transmission regardless of the rotation direction. The dilator includes a front end coil portion (10) and a base end coil portion (20) located on the base end side of the front end coil portion (10) and having a front end portion (20A) connected to the base end (10A) of the front end coil portion (10). The front end coil portion (10) includes a first coil (11) formed by winding a wire in a hollow shape along a first winding direction, and a second coil (12) provided on the outer periphery of the first coil (11) and wound along a winding direction opposite to the first winding direction, i.e., a second winding direction. The base end coil portion (20) includes a third coil (21) formed by winding a wire in a hollow shape along a second winding direction, and a fourth coil (22) provided on the outer periphery of the third coil (21) and wound along the first winding direction.

Description

Technical Field

[0001] The present invention relates to a dilator. Background Art

[0002] Medical devices inserted into body cavities are used in medical treatments such as endoscopy. Patent Document 1 discloses a medical device composed of a hollow stranded wire. The hollow stranded wire has a first layer and a second layer, and the twisting directions of the wires of the first layer and the second layer are opposite.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-107326 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, for treatment, there is known a dilator that dilates a hole formed in the wall of the patient's digestive tract, etc. The hole is expanded by inserting the front end of the dilator into the hole formed in the wall and pressing the tapered portion into the hole. When the hollow stranded wire composed of two layers described in Patent Document 1 is applied to the dilator, the inner layer is tightened and the outer layer is opened depending on the direction in which the dilator is rotated, and the two layers do not contact each other, and sufficient torque transmission may not be obtained.

[0008] An object of the present disclosure is to provide an expander that can obtain high torque transmission performance regardless of the rotation direction.

[0009] Solutions for solving problems

[0010] In order to achieve such a purpose, an expander of one scheme of the present invention comprises: a front end side coil portion; and a base end side coil portion, which is located on the base end side of the above-mentioned front end side coil portion, and the front end portion is connected to the base end portion of the above-mentioned front end side coil portion, the above-mentioned front end side coil portion has: a first coil, which is formed by winding a wire in a hollow shape along a first winding direction; and a second coil, which is arranged on the outer periphery of the above-mentioned first coil and is formed by winding a wire in a second winding direction, and the second winding direction is a winding direction opposite to the first winding direction, and the above-mentioned base end side coil portion has: a third coil, which is formed by winding a wire in a hollow shape along the above-mentioned second winding direction; and a fourth coil, which is arranged on the outer periphery of the above-mentioned third coil and is formed by winding a wire in the above-mentioned first winding direction.

[0011] Preferably, the first winding direction is S-shaped winding, and the second winding direction is Z-shaped winding.

[0012] Preferably, a diameter of a wire material of the third coil is smaller than a diameter of a wire material of the fourth coil.

[0013] Preferably, the base end portion of the front end side coil portion and the front end portion of the base end side coil portion are welded to each other over their entire circumferences.

[0014] Preferably, the first coil and the third coil are respectively formed of different wire materials, and the second coil and the fourth coil are respectively formed of different wire materials.

[0015] The effects of the invention are as follows.

[0016] According to the present disclosure, it is possible to provide an expander capable of obtaining high torque transmission performance regardless of the rotation direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an overall structural diagram of a dilator according to an embodiment.

[0018] Figure 2A yes Figure 1 Cross-sectional view of the dilator at line IIA-IIA.

[0019] Figure 2B yes Figure 1 Cross-sectional view of the dilator at line IIB-IIB.

[0020] Figure 2C yes Figure 1 Cross-sectional view of the expander at line IIC-IIC.

[0021] Figure 3 It is a diagram showing a distal end portion of a dilator according to a modified example. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The dimensions of the dilator shown in the drawings are provided to facilitate understanding of the implementation contents and do not correspond to actual dimensions.

[0023] In addition, in this specification, "front end side" refers to the direction along the length direction of the dilator (the direction along the axial direction of the dilator), and is the direction in which the front end side coil portion is relative to the base end side coil portion. And, "base end side" refers to the direction along the length direction of the dilator, and is the direction on the side opposite to the front end side. In addition, "front end" indicates the end of the front end side in any component or part, and "base end" indicates the end of the base end side in any component or part.

[0024] Figure 1 It is an overall structural diagram of the dilator 1 according to the embodiment of the present disclosure. Figure 1In the figure, the left side is the front end side (distal side) inserted into the body, and the right side is the base end side (hand side, proximal side) operated by a surgeon such as a physician. Figure 2A yes Figure 1 A cross-sectional view of the dilator 1 at line IIA-IIA, Figure 2B yes Figure 1 A cross-sectional view of the dilator 1 at line IIB-IIB, Figure 2C yes Figure 1 A cross-sectional view of the dilator 1 at line IIC-IIC.

[0025] The dilator 1 includes a distal coil portion 10 , a proximal coil portion 20 , and a junction tube 2 .

[0026] The front end side coil portion 10 is located at the front end side in the axial direction of the dilator 1, and has a first coil 11 and a second coil 12. The second coil 12 is wound around the outer peripheral surface of the first coil 11. The wire material constituting the first coil 11 and the second coil 12 is, for example, a metal wire material such as stainless steel and a superelastic alloy such as nickel-titanium, or a resin wire material.

[0027] like Figure 1 , Figure 2A as well as Figure 2B As shown, the first coil 11 is formed into a hollow shape by winding a plurality of (for example, 12) wires. The plurality of wires constituting the first coil 11 are wound along a first winding direction. The first coil 11 has an inner cavity 11a extending from the base end to the front end. The first coil 11 has a straight portion 11B and a tapered portion 11C.

[0028] The straight portion 11B is located at the base end side of the first coil 11, and is connected to the base end side coil portion 20 at the base end. The straight portion 11B has a substantially constant outer diameter from its base end to the front end. The tapered portion 11C is located at the front end side of the straight portion 11B, and is configured to extend from the front end of the straight portion 11B to the front end side, and the outer diameter decreases as it moves toward the front end side.

[0029] The second coil 12 is formed by, for example, winding a wire on the outer peripheral surface 11D of the first coil 11 along a second winding direction opposite to the first winding direction. In the present embodiment, the first winding direction is S-shaped winding, and the second winding direction is Z-shaped winding. The wires constituting the second coil 12 are wound separately. Thus, a spiral convex portion protruding to the outside (the outermost surface, the outermost portion of the dilator 1) is provided on the outer peripheral surface 11D of the first coil 11. The spiral convex portion has a gap between adjacent portions (adjacent metal wires) along the axis of the first coil 11. Due to the threading action of the spiral convex portion, the dilator 1 can be advanced even by the rotation operation of the dilator 1.

[0030] like Figure 1As shown, the base end side coil portion 20 is located at the base end side of the front end side coil portion 10, and has a third coil 21 and a fourth coil 22. The fourth coil 22 is wound around the outer peripheral surface of the third coil 21. The connecting tube 2 is connected to the base end of the base end side coil portion 20. The wire material constituting the third coil 21 and the fourth coil 22 is, for example, a metal wire material such as stainless steel and a superelastic alloy such as nickel-titanium, or a resin wire material.

[0031] like Figure 1 and Figure 2C As shown, the third coil 21 is formed into a hollow shape by winding a plurality of (e.g., 14) metal wires. The plurality of wires constituting the third coil 21 are wound along the second winding direction. The third coil 21 has an inner cavity 21a that passes through from the base end to the front end, and has a substantially constant outer diameter from the base end to the front end. The inner cavity 11a of the first coil 11 and the inner cavity 21a of the third coil 21 are connected to each other.

[0032] The fourth coil 22 is formed by winding a plurality of (e.g., 14) wires along the first winding direction on the outer peripheral surface 21B of the third coil 21. The diameter of the wire constituting the fourth coil 22 is larger than the diameter of the wire constituting the third coil. The outer diameter of the fourth coil 22 is approximately equal to or slightly larger than the outer diameter of the second coil 12.

[0033] In the first coil 11, the third coil 21, and the fourth coil 22, in order to prevent the plurality of wires constituting the front end and the base end thereof from being scattered, welding is performed over the entire circumferential direction thereof. The second coil 12 is welded to the first coil 11 at its front end and the base end, for example. The first coil 11 and the third coil 21 are respectively constituted by different wires, and the second coil 12 and the fourth coil 22 are respectively constituted by different wires.

[0034] The base end 10A of the front end side coil part 10 and the front end 20A of the base end side coil part 20 are welded to each other over their entire circumference. Thus, a welding portion 3 is formed at the connection between the front end side coil part 10 and the front end side coil part 10. The welding portion 3 is tapered toward the front end of the front end.

[0035] The length of the dilator 1 in this embodiment and other embodiments described later is, for example, 2000 mm, or 1650 mm to 2350 mm. The length of the front end side coil portion 10 is, for example, 200 mm, or 50 to 400 mm. The length of the base end side coil portion 20 is, for example, 1800 mm, or 1600 to 1950 mm. The inner diameter at the front end of the first coil 11 is, for example, 0.7 mm, or 0.4 to 1.0 mm. The inner diameter at the base end of the first coil 11 and the front end of the third coil 21 is, for example, 1.5 mm, or 1.0 to 3.0 mm. The outer diameter at the front end of the second coil 12 is, for example, 1.84 mm, or 0.8 to 3.0 mm. The outer diameter at the base end of the second coil 12 is, for example, 2.64 mm, or 1.4 to 5.0 mm. The diameter of the metal wire of the first coil 11 and the third coil 21 is, for example, 0.21 mm, or 0.1 to 0.5 mm. The diameter of the metal wire of the second coil 12 and the fourth coil 22 is, for example, 0.36 mm, or may be 0.1 to 0.5 mm.

[0036] The connecting tube 2 is a part where the surgeon performs rotation operations such as pressing the dilator 1 into the body or pulling out the dilator 1. The front end of the connecting tube 2 is connected to the base end of the base end side coil part 20. The connecting tube 2 is made of resin, for example, and has a hollow shape having an inner cavity connected to the inner cavity 21a of the third coil 21.

[0037] Next, an example of how the dilator 1 is used will be described.

[0038] First, an object is punctured with an introduction needle to create a hole, and then a guide wire is inserted into the lumen of the introduction needle, and the introduction needle is removed.

[0039] Next, the base end of the guide wire is inserted into the inner cavity of the dilator 1, and the dilator 1 is inserted. Next, the dilator 1 is pushed forward while the rotating shaft (the front end side coil part 10 and the base end side coil part 20) is rotated clockwise, thereby expanding the hole of the puncture part. At this time, since the tapered part 11C advances due to the thread action of the spiral convex part caused by the rotation operation of the rotating shaft, the tapered part 11C can be smoothly used to expand the hole. When the dilator 1 is retreated, the rotating shaft is rotated counterclockwise.

[0040] In the dilator 1 of the present embodiment, the distal coil portion 10 includes a first coil 11 formed by winding a wire in a hollow shape along a first winding direction, and a second coil 12 formed by winding a wire in a second winding direction opposite to the first winding direction and provided on the outer periphery of the first coil 11, and the proximal coil portion 20 includes a third coil 21 formed by winding a wire in a hollow shape along the second winding direction, and a fourth coil 22 formed by winding a wire in the first winding direction and provided on the outer periphery of the third coil 21. Moreover, the first winding direction is S-shaped winding, and the second winding direction is Z-shaped winding.

[0041] According to this structure, when the dilator 1 is rotated in the advancing direction (clockwise direction: R direction in the figure) by the threading action of the first coil 11, in the front end side coil part 10, the spacing of the first coil 11 is tightened, and the outer diameter of the first coil 11 is reduced. In addition, the spacing of the second coil 12 is widened, and the outer diameter of the second coil 12 is enlarged. Thus, when the dilator 1 is rotated clockwise while the narrow part is advanced, the second coil 12 is expanded in the radial direction, and the narrow part is enlarged, thereby improving the performance of expanding the narrow part of the dilator 1. On the contrary, in the base end side coil part 20, the spacing of the third coil 21 is widened, thereby the outer diameter of the third coil 21 is enlarged. In addition, the spacing of the fourth coil 22 is tightened, and the inner diameter of the fourth coil 22 is reduced. Thus, the force of the third coil 21 to expand in the radial direction and the force of the fourth coil 22 to shrink in the radial direction interact with each other, and the wires of the third coil 21 and the fourth coil 22 are closely attached to each other. Therefore, the torque transmission performance of the base end side coil part 20 can be improved. Through the above steps, when the dilator 1 is rotated clockwise, the distal end of the dilator 1 expands the stenosis in the radial direction, thereby increasing the dilating force of the stenosis and achieving high torque transmission performance as a whole.

[0042] On the other hand, when the dilator 1 is rotated in the backward direction (counterclockwise), in the base side coil 20, the spacing of the third coil 21 is tightened, and the outer diameter of the third coil 21 becomes smaller. Furthermore, the spacing of the fourth coil 22 is widened, and the outer diameter of the fourth coil 22 becomes larger. On the contrary, in the front end side coil portion 10, the spacing of the first coil 11 is widened, and the outer diameter of the first coil 11 becomes larger. Furthermore, the spacing of the second coil 12 is tightened, and the inner diameter of the second coil 12 becomes smaller. As a result, the force of the first coil 11 to expand in the radial direction and the force of the second coil 12 to shrink in the radial direction interact with each other, and the wires of the first coil 11 and the second coil 12 are closely attached to each other. Therefore, the torque transmission of the front end side coil portion 10 can be improved. In addition, by improving the rigidity of the front end side coil portion 10, the performance of expanding the narrow part of the dilator 1 can be improved. Through the above steps, when the dilator 1 is rotated counterclockwise, the rigidity of the distal end side is increased, thereby improving the performance of dilating the stenosed portion, and also achieving high torque transmission performance as a whole.

[0043] Thus, according to the dilator 1 of this embodiment, the performance of dilating a stenosis can be improved regardless of the rotation direction, and a higher torque transmission can be obtained. Furthermore, since the first winding direction is S-shaped winding and the second winding direction is Z-shaped winding, a higher torque transmission can be obtained in the normal use form of the dilator 1.

[0044] Furthermore, the diameter of the wire material constituting the fourth coil 22 is larger than the diameter of the wire material constituting the third coil. This can increase the torque of the proximal coil portion 20 and, in turn, the torque of the dilator 1.

[0045] The proximal end portion 10A of the distal end coil portion 10 and the distal end portion 20A of the proximal end coil portion 20 are welded to each other over their entire circumferences. Thus, the force applied to the joint tube 2 of the dilator 1 can be reliably transmitted to the distal end coil portion 10 .

[0046] The first coil 11 and the third coil 21 are made of different wires, and the second coil 12 and the fourth coil 22 are made of different wires. Thus, the dilator 1 can be easily manufactured by separately forming the distal coil portion 10 and the proximal coil portion 11 and connecting them.

[0047] As mentioned above, although embodiment of this indication was described, this invention is not limited to the said embodiment, Various deformation|transformation is possible.

[0048] For example, you can also Figure 3As shown in the expander 30, the wire material constituting the fourth coil 22 is wound so that the front end side is not closely attached but is wound separately, and the separation amount is gradually reduced toward the base end side, so that it is closely attached to the base end side. In this way, the rigidity of the expander 30 can be gradually changed from the base end to the front end. The welding portion 33 may not be tapered, but its outer peripheral surface may be configured to be roughly parallel to the axial direction.

[0049] The first coil 11 and the third coil 21 are respectively formed of different wire materials, and the second coil 12 and the fourth coil 22 are respectively formed of different wire materials, but the third coil 21 and the first coil 11 may be formed of the same wire material, and the fourth coil 22 and the second coil 12 may be formed of the same wire material.

[0050] The diameter of the metal wire constituting the fourth coil 22 is larger than the diameter of the metal wire constituting the third coil, but the diameter of the metal wire constituting the fourth coil 22 can also be set to be the same as the diameter of the metal wire constituting the third coil, or it can also be set to be smaller than the diameter of the metal wire constituting the third coil.

[0051] The proximal end portion 10A of the distal end side coil portion 10 and the distal end portion 20A of the proximal end side coil portion 20 are welded to each other over their entire circumferences, but may be welded only at a plurality of locations (eg, four locations) on the outer circumference.

[0052] The distal coil portion 10 includes the straight portion 11B and the tapered portion 11C, but may not include the straight portion 11B. Furthermore, the distal coil portion 10 may include a distal end portion having a substantially constant outer diameter from the base end to the distal end on the distal side of the tapered portion 11C.

[0053] The first coil 11 and the fourth coil 22 are wound along the first winding direction (S-shaped winding), and the second coil 12 and the third coil 21 are wound along the second winding direction (Z-shaped winding), but it is also possible that the first coil 11 and the fourth coil 22 are wound along the second winding direction (Z-shaped winding), and the second coil 12 and the third coil 21 are wound along the first winding direction (S-shaped winding).

[0054] According to this structure, when the dilator 1 is rotated in the forward direction (counterclockwise) by the threading action of the first coil 11, in the front end side coil part 10, the spacing of the first coil 11 is tightened, and the outer diameter of the first coil 11 is reduced. In addition, the spacing of the second coil 12 is widened, and the outer diameter of the second coil 12 is enlarged. Thus, when the dilator 1 is rotated counterclockwise while the narrow part is advanced, the second coil 12 is expanded in the radial direction, and the narrow part is enlarged, thereby improving the performance of expanding the narrow part of the dilator 1. On the other hand, in the base end side coil part 20, the spacing of the third coil 21 is widened, thereby the outer diameter of the third coil 21 is enlarged. In addition, the spacing of the fourth coil 22 is tightened, and the inner diameter of the fourth coil 22 is reduced. Thus, the force of the third coil 21 to expand in the radial direction and the force of the fourth coil 22 to shrink in the radial direction interact with each other, and the wires of the third coil 21 and the fourth coil 22 are closely attached to each other. Therefore, the torque transmission of the base end side coil part 20 can be improved. Through the above steps, when the dilator 1 is rotated counterclockwise, the distal end of the dilator 1 expands the stenosis in the radial direction, thereby increasing the dilating force of the stenosis, and obtaining a higher torque transmission performance as a whole.

[0055] On the other hand, when the dilator 1 is rotated in the backward direction (clockwise), in the base end side coil 20, the spacing of the third coil 21 is tightened, and the outer diameter of the third coil 21 is reduced. In addition, the spacing of the fourth coil 22 is widened, and the outer diameter of the fourth coil 22 is increased. On the contrary, in the front end side coil part 10, the spacing of the first coil 11 is widened, and the outer diameter of the first coil 11 is increased. In addition, the spacing of the second coil 12 is tightened, and the inner diameter of the second coil 12 is reduced. As a result, the force of the first coil 11 to expand in the radial direction and the force of the second coil 12 to shrink in the radial direction interact with each other, and the wires of the first coil 11 and the second coil 12 are closely attached to each other. Therefore, the torque transmission of the front end side coil part 10 can be improved, and in addition, by improving the rigidity of the front end side coil part 10, the performance of expanding the narrow part of the dilator 1 can be improved. Through the above steps, when the dilator 1 is rotated clockwise, the performance of expanding the narrow part can be improved by improving the rigidity of the front end side, and thus a higher torque transmission can be obtained as a whole.

[0056] The number of wires of the first coil 11 and the third coil 21 is not limited to the above number, and may be one or more. In addition, the number of wires of the second coil 12 may also be multiple. In addition, the number of wires of the fourth coil 22 is not limited to the above number, and may be one or more.

[0057] Explanation of symbols

[0058] 1, 30—dilator, 10—front end side coil portion, 10A—base end portion of the front end side coil portion, 11—first coil, 12—second coil, 20—base end side coil portion, 20A—front end portion of the base end side coil portion, 21—third coil, 22—fourth coil.

Claims

1. A dilator, characterized in that: have: a front end side coil portion; and a proximal end coil portion located at the proximal end side of the distal end coil portion, wherein the distal end portion of the proximal end coil portion is connected to the proximal end portion of the distal end coil portion, The front end coil portion includes: A first coil formed by winding a wire material in a hollow shape along a first winding direction; and a second coil, which is disposed on the outer periphery of the first coil and is formed by winding the wire along a second winding direction, the second winding direction being a winding direction opposite to the first winding direction; The base end side coil portion includes: A third coil is formed by winding the wire material in a hollow shape along the second winding direction; The fourth coil is arranged on the outer periphery of the third coil and is formed by winding the wire along the first winding direction.

2. The dilator according to claim 1, characterized in that The first winding direction is S-shaped winding, and the second winding direction is Z-shaped winding.

3. The dilator according to claim 1, characterized in that The base end portion of the front end side coil portion and the front end portion of the base end side coil portion are welded to each other over their entire circumferences.

4. The expander according to claim 2, characterized in that The base end portion of the front end side coil portion and the front end portion of the base end side coil portion are welded to each other over their entire circumferences.

5. The dilator according to any one of claims 1 to 4, characterized in that The first coil and the third coil are respectively formed of different wire materials. The second coil and the fourth coil are respectively formed of different wire materials.

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