Feeding member and medical device

Abstract

To simplify a structure of a feeding member.SOLUTION: A feeding member includes a coil around which a wire is spirally wound. In a cross section of the coil, a plurality of cross sections of the wire are aligned so as to have an annular shape long in one direction, and at least a part of the coil is in a twisted shape so as to have a spiral recess in an outer face.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The technology disclosed herein relates to delivery members and medical devices. [Background technology]

[0002] A known atherectomy device includes a torque shaft and a coil wound around the torque shaft (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2009-542371 Summary of the Invention [Problem to be solved by the invention]

[0004] Known devices leave room for improvement in terms of structural simplicity.

[0005] This specification discloses a technique that can solve the above-mentioned problems. [Means for solving the problem]

[0006] The technology disclosed in this specification can be realized, for example, in the following forms. (1) The feed member disclosed in this specification comprises a coil of wire wound in a spiral shape, and in the cross section of the coil, multiple cross sections of the wire are arranged to form a long ring in one direction, and at least a portion of the coil has a twisted shape so as to have a spiral recess on the outer surface.

[0007] According to the above configuration, the structure of the feed member is simplified.

[0008] (2) In the feed member described in (1) above, the plurality of cross sections of the wire rods may be arranged in the cross section of the coil so as to form an elliptical or oval ring shape.

[0009] According to this configuration, it is possible to easily provide a spiral recess on the outer surface of the coil.

[0010] (3) The medical device disclosed in the present specification includes the delivery member described in (1) or (2) above.

[0011] This configuration simplifies the structure of the medical device.

[0012] The techniques disclosed in this specification can be realized in various forms, for example, in the form of a medical device or a method for manufacturing the same. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a partially cutaway side view of an embodiment of an atherectomy device; [Figure 2] FIG. 10 is a partially enlarged side view of the feed member of the embodiment; [Figure 3] Cross section of line III-III in Figure 2 [Figure 4] Cross section of line IV-IV in Figure 2 DETAILED DESCRIPTION OF THE INVENTION

[0014] An embodiment will be described with reference to FIGS. 1 to 4. FIG. 1 is an explanatory diagram schematically illustrating an atherectomy device 10 according to an embodiment. The atherectomy device 10 is an example of a medical device. FIG. 1 shows a side view of the atherectomy device 10, with a portion cut away. In the atherectomy device 10, the positive Z-axis side is the distal end that is inserted into the body, and the negative Z-axis side is the proximal end that is operated by a surgeon such as a doctor. In each drawing, a portion of the atherectomy device 10 may be omitted. FIG. 1 shows the atherectomy device 10 as a whole in a linear shape parallel to the Z-axis direction. The atherectomy device 10 is flexible enough to be bent. These points also apply to the subsequent drawings.

[0015] In this specification, the distal end of the atherectomy device 10 and each of its components will be referred to as the "tip," the distal end and its vicinity will be referred to as the "tip portion," the proximal end will be referred to as the "proximal end," and the proximal end and its vicinity will be referred to as the "proximal end portion."

[0016] The atherectomy device 10 is a medical device that is inserted into a body lumen such as a blood vessel. As shown in FIG.

[0017] The feeding member 100 includes a coil 110. The coil 110 is a hollow member around which a wire rod 120 is wound in a spiral shape, and extends along a central axis Ax. The wire rod 120 forming the coil 110 may be one or more. Each wire rod 120 may be a single strand, or may be a stranded wire in which multiple strands are twisted together. In this embodiment, the coil 110 is a multi-thread coil in which 18 wire rods 120 are wound.

[0018] The material of the coil 110 is, for example, a metal material, more specifically, stainless steel such as SUS302, SUS304, or SUS316, a superelastic alloy such as a Ni-Ti alloy, piano wire, a nickel-chromium alloy, a cobalt alloy, or tungsten.

[0019] As shown in FIGS. 3 and 4 , in the transverse cross section 110Cs of the coil 110, multiple transverse cross sections 120Cs of the wire material 120 are arranged to form a ring. In this specification, the transverse cross sections 110Cs of the coil 110 and the transverse cross sections 120Cs of the wire material 120 refer to cross sections perpendicular to the central axis Ax of the coil 110. The ring formed by the multiple transverse cross sections 120Cs of the wire material 120 has a shape that deviates from a perfect circle so as to be a ring that is long in one direction. More specifically, the ring formed by the multiple transverse cross sections 120Cs of the wire material 120 may be an elliptical ring or an oval ring. In this specification, the terms “elliptical” and “oval” include shapes that deviate slightly from a strict elliptical or oval shape due to unavoidable manufacturing circumstances. In this embodiment, the multiple transverse cross sections 120Cs are arranged to form an oval ring. In this specification, an "oval" is a shape consisting of two parallel sides and two arcs that connect the ends of the two sides and are arranged facing each other.

[0020] The ratio DS / DL of the minor diameter DS to the major diameter DL of coil 110 may be 0.5 or more and 0.9 or less. In this specification, the major diameter DL of coil 110 is the distance between two parallel lines when the transverse cross section 110Cs of coil 110 is sandwiched between the two parallel lines and the distance between the two lines is maximum. In this specification, the minor diameter DS of coil 110 is the distance between two parallel lines when the transverse cross section 110Cs of coil 110 is sandwiched between the two parallel lines and the distance between the two lines is minimum.

[0021] The coil 110 has a twisted shape such that portions where the major axis Am faces a first direction and portions where the major axis Am faces a second direction perpendicular to the first direction are alternately arranged along the central axis Ax. In FIGS. 2 to 4, the X-axis direction is shown as the first direction and the Y-axis direction is shown as the second direction. In this specification, the major axis Am is the perpendicular line drawn between two parallel lines when the cross section 110Cs of the coil 110 is sandwiched between the two lines and the distance between the two lines is maximum. By being twisted as described above, the coil 110 has a recess 111 on its outer surface, as shown in FIG. 2. The recess 111 extends spirally around the central axis Ax. In this embodiment, the coil 110 has a twisted shape such that the recess 111 is formed on its outer surface along its entire length. The depth Dp of the recess 111 is half the difference between the major axis DL and the minor axis DS. The twist pitch Pt, which is expressed as the distance between two adjacent portions where the major axis Am faces the first direction, may be equal to or greater than 1 diameter of the wire 120 and equal to or less than 400 diameters of the wire 120.

[0022] The distal tip 200 is a hollow member connected to the distal end of the coil 110. The distal tip 200 has a cutting blade at its tip, which cuts diseased tissue. The tip may be joined to the coil 110 by soldering, for example, or may be adhered to the coil 110 by a resin adhesive. A leading guidewire (not shown) can be inserted into the coil 110 and the distal tip 200 connected to the coil 110.

[0023] The outer tube 300 is a cylindrical member with openings at both ends. Most of the feeding member 100, excluding its distal end, is housed inside the outer tube 300. The distal end of the feeding member 100 and the distal tip 200 are exposed from the outer tube 300. The material of the outer tube 300 may be, for example, PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), FEP (tetrafluoroethylene-hexafluoropropylene copolymer), or other resin material that is antithrombogenic, flexible, and biocompatible. The outer tube 300 may also be a resin tube containing a metal braid inside.

[0024] The housing 400 is a container connected to the base end of the outer tube 300. A driving device 410 connected to the feeding member 100 and configured to rotate the feeding member 100 is accommodated inside the housing 400. The driving device 410 is, for example, a motor.

[0025] Next, an example of a method for manufacturing the delivery member 100 used in the above-described atherectomy device 10 will be described below.

[0026] First, a plurality of wires 120 are wound around a rod-shaped core material having an oval cross section to form a multi-thread coil. After the core material is removed, the multi-thread coil is twisted using, for example, a twisting machine. This forms a spiral recess 111 on the surface of the multi-thread coil. The direction in which the multi-thread coil is twisted may be the same as or opposite to the winding direction of the wires 120. Heat may be applied during the twisting process. The application of heat reduces stress caused by the twisting process. In this manner, a feed member 100 having recesses 111 is completed.

[0027] Next, an example of a treatment method using the above-described atherectomy device 10 will be described below.

[0028] The operator inserts a leading guidewire into the blood vessel and advances the leading guidewire to just before the lesion. Next, the operator inserts the atherectomy device 10 into the blood vessel along the leading guidewire and advances the atherectomy device 10 to just before the lesion.

[0029] After the atherectomy device 10 reaches just short of the lesion, the operator drives the drive unit 410 to rotate the feeding member 100 and the distal tip 200, thereby advancing the atherectomy device 10. The distal tip 200, which advances while rotating, cuts the lesion. Small pieces of the lesion produced by cutting move toward the base end through the gap between the outer tube 300 and the coil 110 due to the rotation of the feeding member 100, and are expelled to the outside.

[0030] As described above, according to this embodiment, the atherectomy device 10 includes a feeding member 100. The feeding member 100 includes a coil 110 in which a wire 120 is wound in a spiral shape. In a cross section 110Cs of the coil 110, a plurality of cross sections 120Cs of the wire 120 are arranged to form a ring that is long in one direction. At least a portion of the coil 110 has a twisted shape so as to have a spiral recess 111 on its outer surface. This configuration simplifies the structure of the feeding member 100, and also simplifies the structure of the atherectomy device 10.

[0031] In the cross section 110Cs of the coil 110, the cross sections 120Cs of the wire 120 may be arranged to form an elliptical or oval ring. With this configuration, it is possible to easily provide the spiral recess 111 on the outer surface of the coil 110.

[0032] (Variation) The technology disclosed in this specification is not limited to the above-described embodiments, and can be modified into various forms without departing from the spirit thereof, for example, the following modifications are also possible. (1) A portion of the coil may be twisted to have a spiral recess on the outer surface. (2) The feed member may include only a coil, or may include other members in addition to a coil. (3) The materials of the components in the above embodiment are merely examples and can be modified in various ways. The manufacturing method of the feed member 100 in the above embodiment is merely an example and can be modified in various ways. (4) The medical device may be a device other than an atherectomy device, such as an endoscopic dilator. The technology disclosed in this specification is equally applicable to general medical devices for cutting and removing lesions in biological lumens.

Claims

1. The coil (110) is provided with a wire (120) wound in a spiral shape, In the cross section (110Cs) of the coil (110), a plurality of cross sections (120Cs) of the wire rod (120) are arranged to form a long ring in one direction, At least a portion of the coil (110) is twisted to have a spiral recess (111) on its outer surface. Feed member.

2. 2. The feed member according to claim 1, In the cross section (110Cs) of the coil (110), the multiple cross sections (120Cs) of the wire rod (120) are arranged to form an elliptical or oval ring. Feed member.

3. A medical device (10) comprising a delivery member according to claim 1 or claim 2.

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