Dilator

Abstract

The present invention provides a dilator that can suppress the displacement of a convex portion extending in a spiral shape in the long-axis direction. The dilator comprises: a first coil (2) whose outer diameter increases from the front end toward the base end; and a convex portion (3A) provided on the outer periphery of the first coil (2) and extending in a spiral shape in the long-axis direction of the first coil (2) on the outer periphery of the first coil (2). The convex portions (3A) have gaps (3B) between adjacent convex portions (3A) in the long-axis direction. A covering layer (5) is provided that covers at least the outer peripheral surface (2A) of the first coil (2) located in the gap (3B). The top (3D) of the convex portion (3A) is exposed.

Description

Technical Field

[0001] The present invention relates to dilators. Background Art

[0002] A dilator is known for dilating a hole formed in the wall of a patient's digestive tract or the like for treatment. The hole is dilated by inserting the tip of the dilator into the hole formed in the wall and pushing the tapered portion into the hole. Such a dilator is disclosed in Patent Document 1, for example.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2008-11867 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In this dilator, there is a case where the tapered portion where the push resistance to the hole or the narrow portion becomes high cannot ensure sufficient propulsion force, and thus cannot be fully expanded. Therefore, the following structure is considered: a coil is wound around the outer circumference of the dilator to form a spiral convex portion, and the propulsion force is ensured by the thread effect generated by the rotation to advance the dilator.

[0008] However, when the coil is simply wound around the outer circumference of the dilator, there is a possibility that the helically extending convex portion may be offset in the longitudinal direction.

[0009] An object of the present invention is to provide a dilator capable of suppressing deviation of a convex portion extending in a spiral shape in the longitudinal direction.

[0010] Solutions to Solve Problems

[0011] In order to achieve this purpose, an expander of one embodiment of the present invention comprises: a hollow rotating shaft whose outer diameter increases from the front end to the base end; and a convex portion, which is arranged on the outer periphery of the above-mentioned hollow rotating shaft and extends in a spiral shape along the long axis direction of the above-mentioned hollow rotating shaft on the outer periphery of the above-mentioned hollow rotating shaft, and the above-mentioned convex portion has a gap between the convex portions adjacent to each other along the above-mentioned long axis direction, and a covering layer is provided for covering at least the outer peripheral surface of the above-mentioned hollow rotating shaft located in the above-mentioned gap, and the top of the above-mentioned convex portion is exposed.

[0012] Furthermore, it is preferable that the convex portion is provided so as to be in contact with the outer peripheral surface of the hollow rotating shaft, and the coating layer is interposed between adjacent convex portions and is in contact with the outer peripheral surface of the convex portion.

[0013] Furthermore, it is preferred that the coating layer covers the outer peripheral surface of the hollow rotating shaft, and the convex portion is provided on the coating layer.

[0014] Preferably, the hollow rotating shaft is composed of a first coil formed by winding one or more wires into a hollow shape, and the protrusion is composed of a second coil formed by winding one or more wires around an outer peripheral surface of the hollow rotating shaft.

[0015] Effects of the Invention

[0016] According to the present invention, it is possible to provide a dilator capable of suppressing deviation of a convex portion extending in a spiral shape in the longitudinal direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is an overall view of a dilator according to an embodiment of the present invention.

[0018] Figure 2 This is a cross-sectional view of the vicinity of the boundary between the tapered portion and the base end portion of the dilator.

[0019] Figure 3 It is a cross-sectional view of the vicinity of the boundary between the tapered portion and the base end portion of the dilator according to the modified example.

[0020] Figure 4 It is an overall view of a dilator according to a modified example.

[0021] Figure 5 This is a diagram showing the distal end portion of a dilator according to a modified example.

[0022] Figure 6 This is a diagram showing the distal end portion of a dilator according to a modified example.

[0023] Figure 7 This is a diagram showing the distal end portion of a dilator according to a modified example. DETAILED DESCRIPTION

[0024] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The dimensions of the dilator shown in the drawings are provided for easy understanding of the implementation contents and do not correspond to the actual dimensions.

[0025] Figure 1 This is an overall view of a dilator 1 according to an embodiment of the present invention. Figure 2 It is a cross-sectional view of the vicinity of the boundary between the tapered portion 2D and the proximal end portion 2C of the dilator 1 according to the present embodiment.

[0026] In addition, Figure 1 as well as Figure 2 In 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 doctor.

[0027] exist Figure 1In the embodiment, the dilator 1 comprises: a multilayer body 4, which is composed of a first coil 2 and a second coil 3, wherein the first coil 2 is formed into a hollow shape by winding one or more metal wires, and the second coil 3 is composed of a metal wire wound on the outer peripheral surface 2A of the first coil 2 in the opposite direction (Z winding) to the first coil 2 (S winding); a covering layer 5, which covers the outer peripheral surface 2A of the first coil 2; and a hollow-shaped joint tube 6, which is connected to the base end of the multilayer body 4. In addition, the second coil 3 may be composed of a plurality of metal wires.

[0028] The wire material constituting the first coil 2 and the second coil 3 is, for example, a metal wire material such as stainless steel or a superelastic alloy such as nickel-titanium, or a resin wire material.

[0029] The first coil 2 is formed by winding ten metal wires made of stainless steel, for example. The first coil 2 is hollow and has an inner cavity 2B extending from the base end to the front end. The first coil 2 has a base end 2C, a tapered portion 2D, and a front end 2E. The first coil 2 is equivalent to a hollow rotating shaft.

[0030] The proximal end portion 2C is located on the proximal end side of the dilator 1, and the connecting tube 6 is connected to the proximal end thereof. The proximal end portion 2C has a substantially constant outer diameter from the proximal end to the distal end thereof.

[0031] The tapered portion 2D is located on the distal end side of the base end portion 2C, extends from the distal end of the base end portion 2C toward the distal end side, and is configured such that the outer diameter decreases toward the distal end side.

[0032] The front end portion 2E is located at the front end side of the tapered portion 2D and extends from the front end of the tapered portion 2D to the front end side. The front end portion 2E has a substantially constant outer diameter from its base end to the front end. In this way, the first coil 2 as a hollow rotating shaft increases in outer diameter from the front end toward the base end.

[0033] The second coil 3 is formed by, for example, winding a metal wire on the outer peripheral surface 2A of the first coil 2 in the opposite direction (Z winding) to the first coil 2 (S winding). Here, there is no particular limitation on the spacing of the metal wires, but the metal wires are densely wound on the base end side so that they are in contact with each other. The metal wires are sparsely wound on the front end side of the base end 2C, the tapered portion 2D, and the front end 2E so that the metal wires are separated from each other. The portion (sparsely wound portion) wound separately in the second coil 3 is set to directly contact the outer peripheral surface 2A of the first coil 2, and to form a convex portion 3A extending in a spiral shape along the long axis direction of the first coil 2 on the outer periphery of the first coil 2. The convex portion 3A has a gap 3B between adjacent convex portions 3A along the long axis direction of the first coil 2 (between adjacent metal wires). Utilizing the threading action of the convex portion 3A, the dilator 1 can also be advanced by the rotation operation of the dilator 1.

[0034] Figure 2It is a cross-sectional view of the vicinity of the boundary between the tapered portion 2D and the base end portion 2C of the dilator 1 .

[0035] The coating layer 5 is made of resin, such as Figure 2 As shown, the outer peripheral surface 2A of the first coil 2 located in the gap 3B is covered. That is, the covering layer 5 is between adjacent convex portions 3A, and contacts the outer peripheral surface 3C of the convex portion 3A, covering the outer peripheral surface 3C of the convex portion 3A. In addition, the top 3D of the convex portion 3A is exposed to the outside from the covering layer 5. After the top 3D including the entire circumference of the convex portion 3A is covered with a resin, the resin near the top 3D is peeled off, thereby exposing it to the outside from the covering layer 5. As the resin constituting the covering layer 5, for example, a biocompatible resin material such as polyamide resin and fluororesin, or a hydrophilic coating material, etc. can be listed, and the thickness is, for example, 0.1 to 300 μm.

[0036] The length of the dilator in this embodiment and other embodiments described later is, for example, 2000 mm, preferably 1600 mm to 2500 mm, the length of the front end 2E is, for example, 10 mm, preferably 0 to 100 mm, and the length of the tapered portion 2D is, for example, 30 mm, preferably 5 to 100 mm. The inner diameter of the front end of the first coil 2 is, for example, 0.7 mm, preferably 0.4 to 1.0 mm, and the inner diameter of the base end of the first coil 2 is, for example, 1.5 mm, preferably 1.0 to 3.0 mm. The outer diameter of the front end of the second coil 3 is, for example, 1.84 mm, preferably 0.8 to 3.0 mm, and the outer diameter of the base end of the second coil 3 is, for example, 2.64 mm, preferably 1.4 to 5.0 mm. In addition, the diameter of the metal wire of the first coil 2 is, for example, 0.21 mm, preferably 0.1 to 0.5 mm, and the diameter of the metal wire of the second coil 3 is, for example, 0.36 mm, preferably 0.1 to 0.5 mm.

[0037] The connecting tube 6 as a holding part is a part where the operator pushes the dilator into the body or performs a rotation operation. The front end of the connecting tube 6 is connected to the base end of the first coil 2 and the base end of the second coil 3. The connecting tube 6 is made of resin and has a hollow shape with an inner cavity connected to the inner cavity 2B of the first coil 2.

[0038] The dilator 1 of this embodiment is provided with a coating layer 5 covering the outer peripheral surface 2A of the first coil 2 located in the gap 3B, so that the convex portion 3A extending in a spiral shape can be suppressed from deviating in the long axis direction. In addition, the coating layer 5 is between adjacent convex portions 3A and contacts the outer peripheral surface 3C of the convex portion 3A, so that the convex portion 3A can be further suppressed from deviating in the long axis direction. The coating layer 5 can be used to improve the sliding property of the dilator 1, and the first coil 2 can be suppressed from biting into the biological tissue. Since the top 3D of the convex portion 3A is exposed, the durability of the dilator 1 against friction with the biological tissue when rotating can be improved compared with the case where it is covered by the coating layer 5.

[0039] An example of how to use the dilator will be described below.

[0040] 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 then the introduction needle is removed.

[0041] Next, the base end of the guide wire is inserted into the inner cavity of the dilator, and the dilator is inserted. Next, the dilator is pushed forward while the rotating shaft is rotated to dilate the hole of the puncture portion. At this time, the tapered portion is advanced by the thread action of the spiral convex portion generated by the rotation operation of the rotating shaft, so that the hole can be dilated smoothly by the tapered portion.

[0042] As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, Various deformation|transformation is possible.

[0043] For example, Figure 3 As shown, the covering layer 5 may be covered on the entire outer peripheral surface 2A of the first coil 2, and the convex portion 3A (second coil 3) may be provided on the covering layer 5. Specifically, the convex portion 3A (second coil 3) is wound on the covering layer 5 while the covering layer 5 is pressed radially inwardly of the first coil 2 by the convex portion 3A (second coil 3). Thus, a recess is formed along the convex portion 3A (second coil 3) on the covering layer 5. And, the convex portion 3A (second coil 3) is embedded in the recess. According to this structure, the covering layer 5 is located between adjacent convex portions 3A and contacts the outer peripheral surface 3C of the convex portion 3A, so that the convex portion 3A can be suppressed from being offset in the long axis direction, thereby preventing the biting of biological tissue.

[0044] In addition, if Figure 4 As shown, the dilator 1 of the above embodiment may be a dilator 10 in which the second coil 3 has a gap in the adjacent portion along the axial direction of the first coil 3 to the base end thereof.

[0045] In addition, you can also Figure 5 As shown, the first coil 2 as a hollow rotating shaft does not have a front end 2E, and may also be as shown in FIG. Figure 6As shown, solder (silver-tin solder, gold-tin solder, etc.) flows into the front end portion 2E of the first coil 2 to form the front end portion 7 of a roughly cylindrical hollow shape. In addition, instead of the front end portion 2E (the front end portion 7), a front end piece of the same shape as the front end portion 7 may be provided on the front end side of the tapered portion 2D. In addition, a resin of the resin layer 5 may be additionally provided on the front end side of the front end portion 2E or the tapered portion 2D, and a front end piece made of resin may be formed on the front end side using the additionally provided resin. In addition, a resin material that can melt with the resin of the resin layer 5 may be used to form a sheet on the front end side of the front end portion 2E or the tapered portion 2D.

[0046] In addition, if Figure 7 As shown, the dilator 20 may also be formed by a hollow rotating shaft 21 formed by forming the first coil 2 by casting or the like. The hollow rotating shaft 21 is hollow and has an inner cavity 21A extending from the base end to the front end. In addition, the hollow rotating shaft 21 has a base end 22, a tapered portion 23, and a front end 24, and the outer diameter increases from the front end toward the base end. The material constituting the hollow rotating shaft 21 is not particularly limited as long as the flexibility of the tapered portion 23 and the front end 24 is ensured and biocompatible, and may be, for example, a superelastic alloy material such as stainless steel, nickel-titanium alloy, or a synthetic resin such as polyvinyl chloride resin, polyurethane resin, polyolefin resin, polyamide resin, and fluororesin.

[0047] In addition, the second coil 3 is wound around the outer peripheral surface 21B of the hollow rotating shaft 21 in the same manner as in the above-mentioned embodiment. That is, the second coil 3 is arranged to be in direct contact with the outer peripheral surface 21B of the hollow rotating shaft 21. The covering layer 5 covers the outer peripheral surface 21B of the hollow rotating shaft 21 located in the gap 3B between the adjacent convex portions 3A. That is, the covering layer 5 is interposed between the adjacent convex portions 3A, and is in contact with the outer peripheral surface 3C of the convex portion 3A, covering the outer peripheral surface 3C of the convex portion 3A. In addition, the top 3D of the convex portion 3A is exposed to the outside from the covering layer 5.

[0048] The covering layer 5 may also be covered on the entire circumference of the outer peripheral surface 21B of the hollow rotating shaft 21, and the convex portion 3A (second coil 3) may be provided on the covering layer 5. Specifically, the convex portion 3A (second coil 3) is wound on the covering layer 5 while pressing the covering layer 5 toward the radial inner side of the hollow rotating shaft 21 by the convex portion 3A (second coil 3). Thus, a recess is formed along the convex portion 3A (second coil 3) on the covering layer 5. And, the convex portion 3A (second coil 3) is embedded in the recess. According to this structure, the covering layer 5 is interposed between adjacent convex portions 3A and contacts the outer peripheral surface 3C of the convex portion 3A, so that the convex portion 3A can be suppressed from being offset in the long axis direction, thereby preventing the biting of biological tissue.

[0049] According to the dilator 20, a coating layer 5 covering the outer peripheral surface 2A of the second coil 2 located in the gap 3B is also provided, so that the convex portion 3A extending in a spiral shape can be suppressed from deviating in the long axis direction. The coating layer 5 is interposed between adjacent convex portions 3A and contacts the outer peripheral surface 3C of the convex portion 3A, so that the convex portion 3A can be further suppressed from deviating in the long axis direction. Since the top 3D of the convex portion 3A is exposed, the durability of the dilator 1 against friction with biological tissues etc. when rotating can be improved compared with the case where the coating layer 5 is covered.

[0050] Alternatively, the outer peripheral surface of the second coil 3 which is densely wound on the base end side of the first coil 2 or the hollow rotating shaft 21 may be coated with resin.

[0051] In the above-described embodiment, the first coil 2 is described as a hollow coil body composed of ten wires, but the number of wires is not limited to ten, and may be one or more.

[0052] exist Figure 7 In the embodiment shown, various coatings may be provided on the surface of the hollow rotating shaft 21 (including the area between the rotating shaft and the spiral convex portion). Examples of such coatings include a protective film on the surface of the hollow rotating shaft 21 (a representative example is a plating film), a base film for improving the adhesion between the hollow rotating shaft 21 and the second coil 3, and the like.

[0053] exist Figure 1 to Figure 7 In the embodiment shown, the spiral convex portion preferably does not constitute a cutting tool. The dilator of this embodiment dilates a hole pre-formed in an object (e.g., the wall of a patient's digestive tract such as the stomach). Therefore, if the spiral convex portion constitutes a cutting tool, it will damage the biological tissue on the inner surface of the hole.

[0054] Therefore, the spiral convex portion is preferably in its cross-sectional shape (for example, Figure 2 The end portion of the radially outer side of the rotation axis (the shape of the cross section of the spiral convex portion 3A orthogonal to the spiral direction shown in FIG. 1 ) does not have an acute corner. That is, the end portion preferably has a portion consisting of a shape including an obtuse corner or a curve (for example, a curve including a part of a circle or an ellipse).

[0055] Explanation of symbols

[0056] 1, 10, 20—expander, 2—first coil, 2A—outer peripheral surface, 3—second coil, 3A—convex portion, 3B—gap, 3D—top, 5—cladding layer, 21—hollow rotating shaft.

Claims

1. A dilator, characterized in that: have: a hollow rotating shaft whose outer diameter increases from the front end toward the base end; and a convex portion, which is provided on the outer periphery of the hollow rotating shaft and extends in a spiral shape along the long axis direction of the hollow rotating shaft on the outer periphery of the hollow rotating shaft, The convex portions have gaps between adjacent convex portions along the major axis direction. A covering layer is provided for covering at least the outer peripheral surface of the hollow rotating shaft located in the gap, The coating layer is interposed between adjacent convex portions and contacts the outer peripheral surface of the convex portion in a manner that no concave portion exists between the outer peripheral surface of the convex portion and the outer peripheral surface of the hollow rotating shaft, thereby coating a portion of the outer peripheral surface of the convex portion. The top of the protrusion is exposed to the outside from the coating layer.

2. The dilator according to claim 1, characterized in that The convex portion is provided so as to be in contact with the outer peripheral surface of the hollow rotating shaft.

3. The dilator according to claim 1, characterized in that The coating layer covers the outer peripheral surface of the hollow rotating shaft. The convex portion is provided on the cladding layer.

4. The dilator according to any one of claims 1 to 3, characterized in that: The hollow rotating shaft is composed of a first coil formed by winding one or more wires into a hollow shape. The convex portion is formed by a second coil formed by winding one or more wires around the outer peripheral surface of the hollow rotating shaft.

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