JP2023002009A - multilayer coil body - Google Patents

Abstract

To provide a multilayer coil body capable of achieving both enough torque transmission property and high flexibility.SOLUTION: A multilayer coil body 1 includes: a hollow first coil layer 11 where a first coil 11w is spirally wound around; a third coil layer 31 provided so as to cover the first coil layer 11 and where the third coil 31w is spirally wound around; and a second coil layer 21 provided adjacent between the first coil layer 11 and the third coil layer 31 and where a second coil 21w is spirally wound around. A cross sectional area of at least one coil 21w composing the second coil layer 21 is larger than a cross sectional area of at least one coil 31w composing the first coil layer 11 and the third coil layer 31, and a gap 21g is formed between at least a part of the adjacent second coils 21w in a long axis direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to a multilayer coil body.

2. Description of the Related Art Elongated medical devices such as catheters are known as devices that are inserted into body cavities such as blood vessels to treat lesions and the like. Such a medical instrument is required to have excellent torque transmissibility in order to reliably transmit the rotational force at hand to the distal end portion of the medical instrument inserted into the body cavity when rotating the distal end portion.

As a medical device as described above, for example, a device provided with a coil body having a plurality of coil layers arranged adjacent to each other in a direction (radial direction) perpendicular to the longitudinal direction of the medical device is disclosed. (See Patent Document 1, for example).

JP 2019-107326 A

However, although the coil body used in the above-described conventional medical device can ensure sufficient torque transmissibility, it is difficult to ensure high flexibility to follow the complicatedly curved shape of the body cavity. , is not always sufficient.

SUMMARY OF THE INVENTION The present invention has been made in view of the circumstances described above, and an object thereof is to provide a multilayer coil body capable of achieving both sufficient torque transmissibility and high flexibility.

Some aspects of the disclosure include:
(1) a hollow first coil layer in which a first winding is spirally wound;
a third coil layer provided to cover the first coil layer and having a third winding spirally wound thereon;
a second coil layer provided adjacent to between the first coil layer and the third coil layer and having a second coil wound spirally thereon. being a body,
at least one winding forming the second coil layer has a larger cross-sectional area than at least one winding forming the first coil layer and the third coil layer;
A multilayer coil body characterized in that a gap is formed between at least some of the second windings adjacent to each other in the longitudinal direction,
(2) The multilayer coil body according to (1) above, wherein the contour shape of the outermost circumference in the cross section of the second winding is substantially rectangular;
(3) The multilayer coil body according to (1) or (2), wherein the gaps formed between the second windings include two or more gaps having different lengths in the longitudinal direction. ,
(4) the multilayer coil assembly of (3), wherein the second winding comprises a radiopaque material; and (5) a conductor in the gap formed between the second windings. The multilayer coil body according to any one of (1) to (4) above, provided with

In this specification, the term "winding" means a linear member spirally wound to form a coil layer. The member may be a single wire (single wire) or a twisted wire. The "cross-sectional area of the winding" is the cross-sectional area of the winding perpendicular to the spiral direction. That is, it can also be said to be a cross-sectional area in a cross section orthogonal to the advancing direction (spiral direction) of the spirally advancing winding.

INDUSTRIAL APPLICABILITY The present invention can provide a multilayer coil body capable of achieving both sufficient torque transmissibility and high flexibility.

1 is a schematic longitudinal sectional view showing the entirety of a first embodiment; FIG. 1 is a schematic longitudinal sectional view showing part of the first embodiment; FIG. It is a schematic longitudinal cross-sectional view which shows a part of modification. FIG. 4 is a schematic longitudinal sectional view showing part of the second embodiment; FIG. 11 is a schematic longitudinal sectional view showing part of a third embodiment; It is a schematic longitudinal cross-sectional view showing the whole of the fourth embodiment. It is a schematic longitudinal cross-sectional view which shows the whole 5th Embodiment. FIG. 12 is a schematic vertical cross-sectional view showing the entirety of a sixth embodiment; FIG. 11 is a schematic vertical cross-sectional view showing part of a sixth embodiment; It is a schematic longitudinal cross-sectional view which shows a part of modification.

A multilayer coil body of the present disclosure includes a hollow first coil layer in which a first winding is helically wound, a hollow first coil layer provided to cover the first coil layer, and a third winding helically. a third coil layer wound in a shape, and a second coil wound spirally provided between the first coil layer and the third coil layer so as to be adjacent to each other; and a second coil layer, wherein the cross-sectional area of at least one winding constituting the second coil layer is equal to that of the first coil layer and the third coil. A gap is formed between at least a portion of the second windings adjacent to each other in the longitudinal direction, the gap being larger than the cross-sectional area of at least one winding constituting the layer.

In this specification, the term "distal end side" means a direction along the long axis direction of the multilayer coil body, which is a direction proceeding toward the treatment site. The term "proximal side" means a direction along the longitudinal direction, which is opposite to the distal side. In addition, the term “distal end” refers to the distal end of any member or site, and the term “basal end” refers to the proximal end of any member or site. The terms "longitudinal direction" and "radial direction" mean the longitudinal direction and the radial direction (perpendicular to the longitudinal direction) of the multi-layer coil body, respectively, unless otherwise specified.

Hereinafter, first to sixth embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited only to the embodiments described in the drawings. In addition, the dimensions shown in each drawing are dimensions shown to facilitate understanding of the contents of implementation, and do not necessarily correspond to actual dimensions. In each figure, the left side of the drawing shows the distal end side of the multilayer coil body, and the right side shows the base end side of the multilayer coil body.

[First embodiment]
1 and 2 are schematic diagrams showing the first embodiment. As shown in FIGS. 1 and 2, the multilayer coil body 1 is generally composed of a first coil layer 11, a second coil layer 21, and a third coil layer 31. As shown in FIGS.

The first coil layer 11 is a hollow layer in which the first winding 11w is spirally wound. Specifically, for the first coil layer 11, for example, a single wire (single wire) or twisted wire having a circular cross section is used as the first winding 11w, and this member is wound in a single wire or multiple wires. It can be formed by turning. The first windings 11w adjacent in the longitudinal direction may be in contact with each other or may be separated from each other. When the first windings 11w are separated from each other, the gap between the first windings 11w may be configured to be smaller than the gap between the second windings 21w, which will be described later. shown). In this embodiment, a single wire 111w having a circular cross section is used as the first winding 11w, and the first winding 11w is wound in a single wire so that adjacent first windings 11w are in contact with each other. are placed. A lumen 1 h is formed inside the first coil layer 11 . For example, a guide wire (not shown) or the like can be passed through the lumen 1h.

The second coil layer 21 is provided so as to be adjacent between the first coil layer 11 and a third coil layer 31 described later, and is a layer in which the second winding 21w is spirally wound. is. Specifically, for example, the second coil layer 21 is formed by using a single wire (single wire) or twisted wire as the second winding 21w and winding this member in a single or multiple wires. be able to.

The contour shape of the outermost periphery of the cross section of the second winding 21w may be circular or substantially rectangular. When the outline shape is rectangular, the cross-sectional area of the second winding 21w can be increased while saving space, and the torque transmissibility can be effectively improved by the second winding having a rectangular cross-section. can be done. In the present embodiment, a single wire 211w having a rectangular outermost contour in cross section is used as the second winding 21w. is exemplified.

When the contour shape of the cross section of the second winding 21w is rectangular, the aspect ratio of the cross section (the length to width ratio of the rectangular shape) is, for example, vertical dimension:horizontal dimension=1:10 (flat shape) to It may be set to 1:1 (square). In the case of a flat shape, it is preferable that the flat surfaces are arranged so as to be in contact with the first and third coil layers 11 and 31 . Thereby, it is possible to prevent the multi-layer coil body 1 from being crushed by the pressure from the radially outer side, and to further improve the torque transmissibility among the torque transmissibility and the flexibility. In addition, in the case of a square shape, it is possible to further enhance flexibility among torque transmissibility and flexibility.

The third coil layer 31 is provided so as to cover the first coil layer 11, and is a layer in which a third winding 31w is spirally wound. Specifically, the third coil layer 31 uses, for example, a single wire (single wire) or twisted wire having a circular cross section as the third winding 31w, and this member is wound in a single wire or multiple wires. It can be formed by turning. The third windings 31w adjacent in the longitudinal direction may be in contact with each other or may be separated from each other. When the third windings are separated from each other, as shown in FIG. 3, the gap A31g between the third windings A31w is configured to be smaller than the gap 21g between the second windings 21w, for example. You may In this embodiment, a single wire 311w having a circular cross section is used as the third winding 31w, and the third winding 31w is wound in a single line so that adjacent third windings 31w are in contact with each other. The formed third coil layer 31 is illustrated (see FIG. 2).

Here, a gap 21g is formed between at least some of the adjacent second windings 21w in the longitudinal direction. The gap 21g may be formed between each of the adjacent second windings, is formed only between specific second windings, and is formed only between the specific second windings and the second windings other than the specific second windings. The windings may be in contact with each other.

The length L of the gap 21g in the long axis direction can be appropriately determined according to the flexibility required for each part of the multilayer coil body 1 in the long axis direction. The length L of the gap 21g can be set to 0.001 mm to 1 mm, for example. When the length L of the gap 21g is large, the flexibility of the multi-layer coil body can be increased at the corresponding portion, and when the length L of the gap 21g is small, the rigidity of the multi-layer coil body can be increased at the corresponding portion. In this embodiment, the multilayer coil body 1 in which the second windings 21w having the same length L and the gap 21g adjacent to each other is exemplified.

Further, in the multilayer coil body 1, the cross-sectional area of at least one winding 21w constituting the second coil layer 21 is equal to that of at least one winding constituting the first coil layer 11 and the third coil layer 31. It is configured to be larger than the cross-sectional area of the lines 11w and 31w. More specifically, at least one winding 21w forming the second coil layer 21 has a cross-sectional area of It is configured to be larger than the cross-sectional area of the winding having the largest cross-sectional area.

In the multilayer coil body 1 of this embodiment, each of the first winding 11w and the third winding 31w is composed of a single wire and a single wire, and the second winding 21w is composed of a single wire and a single wire. Consists of windings. Therefore, the cross-sectional area of the single wire 211w (strand wire) forming the second winding 21w is the same as the cross-sectional area of the single wire 111w (strand wire) forming the first winding 11w and the cross-sectional area of the third winding 31w. It is configured to be larger than any of the cross-sectional areas of the single wires 311w (element wires) that constitute it.

The winding directions of radially adjacent windings may be opposite to each other (for example, the first winding is S-twisted, the second winding is Z-twisted, and the third winding is S-twisted). twisting, etc.). When the winding directions of the windings are opposite to each other in this way, when the multi-layered coil body is rotated about the longitudinal axis, the directions of longitudinal forces acting on radially adjacent windings can be made opposite to each other. Even if the multilayer coil body is rotated in any direction, it is possible to suppress a decrease in torque transmissibility due to a gap between windings adjacent to each other in the long axis direction.

From the viewpoint of imparting antithrombogenicity and biocompatibility, for example, stainless steel such as SUS316; - Superelastic alloys such as Ti alloys; radiopaque metals such as platinum and tungsten; The wire material of each winding may be the same material as each other, or may contain different materials.

As described above, since the multilayer coil body 1 has the above structure, it is possible to achieve both sufficient torque transmissibility and high flexibility. In addition, since the multilayer coil body 1 can be made hard or soft by appropriately adjusting the length L (interval) of the gap 21g, the balance between flexibility and rigidity can be appropriately adjusted.

[Second embodiment]
FIG. 4 is a schematic diagram showing a second embodiment. As shown in FIG. 4, the multilayer coil body 2 is generally composed of a first coil layer 11, a second coil layer 22, and a third coil layer 31. As shown in FIG. The multilayer coil body 2 differs from the first embodiment in that it includes a second coil layer 22 . Since the first coil layer 11 and the third coil layer 31 are the same as those in the first embodiment, the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted. Also, the configuration other than the configuration of the second coil layer 22 described below is the same as that of the first embodiment.

The second coil layer 22 is provided so as to be adjacent between the first coil layer 11 and the third coil layer 31, and is a layer in which the second winding 22w is spirally wound. In the present embodiment, three single wires 221w, 222w, and 223w having the same cross-sectional area and a rectangular outermost contour in cross section are used as the second winding 22w. A second coil layer 22 wound with a strip is illustrated.

In the multilayer coil body 2 , gaps are formed between adjacent second windings 22 w in the longitudinal direction of the second coil layer 22 . Specifically, in the multilayer coil body 2, the three single wires 221w, 222w, and 223w that constitute the second winding 22w form a set while being in contact with each other in the longitudinal direction, and form a set of windings that are adjacent in the longitudinal direction. A gap 22g is formed between the wires (three second windings 22w).

In the multilayer coil body 2 of this embodiment, each of the first winding 11w and the third winding 31w is composed of a single wire and a single winding, and the second winding 22w is a single wire and three windings ( It consists of multiple windings. Specifically, the cross-sectional area of at least one winding wire 21w forming the second coil layer 21 is equal to the cross-sectional area of at least one winding wire 21w forming the first coil layer 11 and the third coil layer 31. It is configured to be larger than the cross-sectional area of 31w. More specifically, at least one winding 21w forming the second coil layer 21 has a cross-sectional area of is larger than the cross-sectional area of the winding having the largest cross-sectional area.

As described above, since the multilayer coil body 2 has the above structure, it is possible to achieve both sufficient torque transmissibility and high flexibility. In addition, since the multilayer coil body 2 can be made hard or soft by appropriately adjusting the length L (interval) of the gap 22g, the balance between flexibility and rigidity can be appropriately adjusted.

[Third embodiment]
FIG. 5 is a schematic longitudinal sectional view showing a third embodiment. As shown in FIG. 5, the multilayer coil body 3 is generally composed of a first coil layer 11, a second coil layer 23, and a third coil layer 31. As shown in FIG. The multilayer coil body 3 differs from the first embodiment in that it includes a second coil layer 23 . Since the first coil layer 11 and the third coil layer 31 are the same as those in the first embodiment, the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted. Also, the configuration other than the configuration of the second coil layer 23 described below is the same as that of the first embodiment.

The second coil layer 23 is provided so as to be adjacent between the first coil layer 11 and the third coil layer 31, and is a layer in which the second winding 23w is spirally wound. In the present embodiment, a single single wire 231w having a rectangular outermost contour in cross section is used as the second winding 23w, and a single wire 231w is wound to form a second coil layer. 23 are exemplified.

In the multilayer coil body 3 , gaps 23 g are formed between adjacent second windings 23 w in the long axis direction of the second coil layers 23 . A gap 23g formed between the second windings 23w in the multilayer coil body 3 includes two or more gaps 23g having different lengths in the longitudinal direction (for example, gaps 231g and 232g).

As the gap 23g with different lengths, for example, the length L of the gap 23g increases monotonously and/or stepwise along the long axis direction, or the length L differs only at a predetermined portion in the long axis direction. (the length L of the gap 23g is large or small only at a predetermined portion). In this embodiment, the second coil layer 23 is exemplified in which the length L of the gap 23g monotonically increases toward the tip side.

In the multilayer coil body 3, the second winding 23w may contain radiopaque material (for example, X-ray opaque material, etc.). Since the wire material constituting the second winding 23w contains a radiopaque material, in the radiographic image, in the long axis direction from the relationship with the length L of the contrasted gap and the length of other gaps The position of the gap can be specified, and the multilayer coil body can be manipulated more accurately within the body cavity.

Examples of the radiopaque material include gold, platinum, tungsten, or alloys containing these elements (eg, platinum-nickel alloys, etc.). In addition, the radiopaque material may be a combination of the radiopaque material and the radiotransmitting material, such as a material coated on the surface of a material that is not radiopaque (radiotransmitting material). .

As described above, since the multilayer coil body 3 includes two or more gaps 23g having different lengths L in the longitudinal direction, the flexibility of the multilayer coil body 3 in the longitudinal direction can be varied. In addition, since the multilayer coil body 3 can be made hard or soft by appropriately adjusting the length L (interval) of the gap 23g, the balance between flexibility and rigidity can be appropriately adjusted.

[Fourth embodiment]
FIG. 6 is a schematic longitudinal sectional view showing a fourth embodiment. In this embodiment, a catheter using the multilayer coil body of the present disclosure is illustrated. The catheter C, as shown in FIG. 6, is generally composed of a multilayer coil body 4, a distal tip 44, and a base portion 54. As shown in FIG.

The multilayer coil body 4 includes a first coil layer 11 , a second coil layer 24 and a third coil layer 31 . Since the first coil layer 11 and the third coil layer 31 are the same as those in the first embodiment, the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted. Also, the configuration other than the configuration of the second coil layer 24 described below is the same as that of the first embodiment.

The second coil layer 24 in the catheter C is arranged such that the length L of the gap 241g between the second windings 24w at the distal end of the multilayer coil body 4 is longer than the length L of the gap 242g at the proximal end. It is configured. As a result, the distal end portion of the multilayer coil body 4 can be made more flexible than the proximal end portion, and the catheter C can be advanced more smoothly while the distal end portion follows the curved body cavity.

The distal tip 44 is a member joined to one end of the multilayer coil body 4 . Specifically, the distal end tip 44 is formed so that the distal end portion thereof has a rounded shape toward the distal end side so that the multilayer coil body 4 can easily move in a body cavity such as a blood vessel. . Distal tip 44 has a lumen 44h with an opening 44a at its distal end.

As a method of joining the distal tip 44 and the multilayer coil body 4, for example, the distal ends of the first winding 11w, the second winding 24w, and the third winding 31w constituting the multilayer coil body 4 are connected to the distal ends. A method of burying by welding or the like in the base end portion of the tip 44 can be adopted.

The material forming the distal tip 44 preferably has antithrombogenicity, biocompatibility, and flexibility so as to reduce the impact on body cavities and the like. Examples of such materials include resin materials such as polyurethane and polyurethane elastomer.

The base 54 is a member for gripping the catheter C by the operator. The base portion 54 has, for example, a lumen 54h that is connected to the proximal end portion of the multilayer coil body 4 and communicates with the lumen 4h of the multilayer coil body 4 . An opening 54a is formed at the proximal end of the lumen 54h. The shape of the base portion 54 is not particularly limited as long as the effects of the present invention are not impaired.

Here, a lumen M is formed by the lumen 44h of the distal tip 44, the lumen 4h of the multilayer coil body 4, and the lumen 54h of the base portion 54. As shown in FIG. A medical instrument such as a guide wire (not shown) is inserted through this lumen M, for example.

Next, the mode of use of the catheter C will be described. Here, the catheter C is used as a guiding catheter to exemplify a technique of dilating a constricted portion of a coronary artery of the heart with a balloon catheter.

Prior to using the catheter C, first, a guide wire A (not shown) is inserted into a blood vessel, and its tip is fed near the entrance of the coronary arteries of the heart. Next, the guide wire A is inserted into the lumen M of the catheter C, and the catheter C is pushed forward along the guide wire A into the blood vessel so that the tip reaches the entrance of the coronary arteries of the heart. At this time, the catheter C is fed while following the curvature of the blood vessel.

Next, the guide wire A is pulled out and replaced with a thinner guide wire B (not shown) for a balloon catheter, and the distal end of the guide wire B is passed through the catheter C to reach a position where it passes through the stenosis. Next, a balloon catheter (not shown) is inserted along the guide wire B to the inside of the constriction, and treatment is performed by dilating the constriction with the balloon. After this treatment, the balloon catheter, the guide wire B, and the catheter C are removed from the body in this order to complete the procedure.

As described above, since the catheter C has the above-described structure, the rotational force applied to the base portion 54 is reliably transmitted to the distal end portion of the catheter C due to the excellent torque transmissibility and high flexibility of the multilayer coil body 4. In addition, it is possible to exhibit high followability even in blood vessels that are complicatedly curved. In addition, since the multilayer coil body 4 can be made hard or soft by appropriately adjusting the length L (interval) of the gap 24g, the balance between flexibility and penetrating force in the catheter C can be adjusted appropriately. .

[Fifth embodiment]
FIG. 7 is a schematic longitudinal sectional view showing a fifth embodiment. In this embodiment, a guidewire using the multilayer coil body of the present disclosure is illustrated. The guide wire G1, as shown in FIG. 7, is generally composed of a core shaft 65, a multilayer coil body 5, a distal fixing portion 75, and a proximal fixing portion 85. As shown in FIG.

The core shaft 65 is a longitudinal shaft. The core shaft 65 can be configured to have, for example, an enlarged diameter portion 652 , a small diameter portion 651 and a large diameter portion 653 .

The expanded diameter portion 652 is a portion that expands in diameter toward the base end side. The small-diameter portion 651 is a portion whose proximal end is positioned at the distal end of the enlarged-diameter portion 652 and extends toward the distal end side. The large-diameter portion 653 is a portion whose tip is positioned at the proximal end of the enlarged-diameter portion 652 and extends toward the proximal end side. In addition, each of the small diameter portion 651 and the large diameter portion 653 can be configured to have a constant outer diameter along the long axis direction of the core shaft 65 .

From the viewpoint of improving the flexibility of the guide wire G1 and imparting antithrombogenicity and biocompatibility, the core shaft 65 may be made of, for example, stainless steel such as SUS304, or superelasticity such as Ni—Ti alloy. An alloy or the like can be adopted.

The multilayer coil body 5 includes a first coil layer 11 , a second coil layer 25 and a third coil layer 31 . Since the first coil layer 11 and the third coil layer 31 are the same as those in the first embodiment, the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted. Also, the configuration other than the configuration of the second coil layer 25 described below is the same as that of the first embodiment.

The second coil layer 25 of the guide wire G1 is configured such that the length L of the gap 251g at the distal end of the multilayer coil body 5 is longer than the length L of the gap 252g at the proximal end. As a result, the distal end portion of the multilayer coil body 5 can be made more flexible than the proximal end portion, and the guide wire G1 can be advanced more smoothly while following the curved body cavity.

The distal end fixing portion 75 is a portion for fixing the distal end portion of the multilayer coil body 5 and the distal end portion of the core shaft 65 . Specifically, the distal end fixing portion 75 can be formed, for example, so that the distal end portion has a substantially hemispherical shape that is convexly curved toward the distal end side. As a result, resistance when the guide wire G1 advances through the blood vessel can be reduced, and the guide wire G1 can be smoothly inserted.

As a method for forming the tip fixing portion 75, for example, tip portions of the first winding 11w, the second winding 25w, and the third winding 31w constituting the core shaft 65 and/or the multilayer coil body 5 are A method of forming by melting, a method of joining the core shaft 65 and the multi-layer coil body 5 using brazing material, or the like can be employed. Examples of the brazing material include metal brazing such as Sn--Pb alloy, Pb--Ag alloy, Sn--Ag alloy and Au--Sn alloy.

The base end fixing portion 85 is a portion for fixing the base end portion of the multilayer coil body 5 and the core shaft 65 . Specifically, the base end fixing portion 85 can be formed on the enlarged diameter portion 652 of the core shaft 5, for example.

As a method for forming the base end fixing portion 85, for example, the base end portions of the first winding 11w, the second winding 25w, and the third winding 31w constituting the multilayer coil body 5 are melted. A method of joining the core shaft 65 and the multi-layered coil body 5 using brazing material, or the like can be employed. As the brazing material, for example, the same brazing material as the brazing material used for forming the tip fixing portion 75 can be used.

In addition, as a mode of use of the guide wire G1, for example, a mode similar to the guide wire A and the guide wire B described in the mode of use of the catheter C of the fourth embodiment can be exemplified.

As described above, since the guide wire G1 is configured as described above, the excellent torque transmissibility and high flexibility of the multi-layered coil body 5 allow the rotational force applied to the proximal end of the core shaft 65 to be transferred to the guide wire G1. It can be reliably transmitted to the distal end portion, and can exhibit high followability even in a complicatedly curved blood vessel. In addition, by appropriately adjusting the length L (interval) of the gap 25g, the multilayer coil body 5 can be made hard or soft. can.

[Sixth embodiment]
8 and 9 are schematic longitudinal sectional views showing a sixth embodiment. In this embodiment, a guide wire in which conductors (lead wires) are routed using the multilayer coil body of the present disclosure is exemplified. As shown in FIGS. 8 and 9, the guide wire G2 is roughly composed of a core shaft 65, a multilayer coil body 6, a distal fixing portion 75, a proximal fixing portion 85, a sensor 961, and a lead wire 962. , and a covering member 963 . The guide wire G2 differs from the fifth embodiment in that it includes a multilayer coil body 6, a sensor 961, a lead wire 962 and a covering member 963. Since the core shaft 65, the distal end fixing portion 75, and the proximal end fixing portion 85 are the same as those in the fifth embodiment, the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted.

The multilayer coil body 6 includes a first coil layer 11 , a second coil layer 25 and a third coil layer 36 . Since the first coil layer 11 and the second coil layer 25 are the same as those of the fifth embodiment, the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted. Also, the configuration other than the configuration of the third coil layer 36 described below is the same as that of the fifth embodiment.

In the third coil layer 36 of the guide wire G2, adjacent third windings 36w in the longitudinal direction are separated from each other. The gap 36g between the third windings 36w can be configured to be smaller than the gap 25g between the second windings 25w, for example.

The base end of the sensor 961 is connected to the tip of a lead wire 962, which will be described later, and is arranged along the spiral gap 25g formed between the adjacent second windings 25w. The distal end of the sensor 961 can be, for example, embedded in the distal fixation portion 75 or positioned to abut or be adjacent to the proximal end of the distal fixation portion 75 .

Examples of the sensor 961 include a temperature sensor, a pressure sensor, and the like.

As for the shape of the sensor 961, a linear or ribbon-like sensor can be preferably used so as to fit in the gap 25g formed between the adjacent second windings 25w.

The lead wire 962 is an electrical conductor that electrically connects the sensor 961 and an external measuring device body (not shown). A tip side portion of the lead wire 962 is provided in a gap 25g formed between the second windings 25w. Specifically, the tip side portion of the lead wire 962 is arranged along the spiral gap 25g formed between the adjacent second windings 25w. The base end portion of the lead wire 962 may, for example, extend linearly along the longitudinal direction on the outer peripheral surface of the core shaft 65 .

It is preferable that the outer circumference of the lead wire 962 is positioned inside (in the direction of the central axis of the guide wire G2) the outer circumference of the second winding 25w in the multilayer coil body 6. As shown in FIG. As a result, direct application of a large external force to the lead wire 962 can be suppressed, and the lead wire 962 can be prevented from being deformed or damaged.

As a material for the lead wire 962, a metal different from the material for the first, second and third windings 11w, 25w and 36w is preferable. It is more preferable to use a metal having a lower resistance than the material forming 25w and 36w. Examples of such materials include gold, silver, copper, and alloys containing these. These materials have lower rigidity and a smaller elastic region than stainless steel such as SUS316 and superelastic alloys such as Ni—Ti alloys, which constitute the multilayer coil body 6 .

The covering member 963 is a member that electrically insulates the sensor 961 and the lead wire 962 from surrounding members such as the multilayer coil body 6 and body tissues such as blood vessels and blood, and fixes the sensor 961 and the lead wire 962 to the multilayer coil body 6. .

Examples of the material forming the covering member 963 include thermosetting electrically insulating resin such as polyimide; thermoplastic electrically insulating resin such as polyamide. For example, after wiring the sensor 961 and the lead wire 962 to the multilayer coil body 6 and the core shaft 65, a resin composition for forming the resin is applied to the sensor 961 and the lead wire by dipping, spraying, or the like. It can be formed by coating the outer periphery of the wire 962 and heat-treating it.

As described above, since the guide wire G2 has the above structure, the lead wire 962 having a smaller rigidity and a smaller elastic region than, for example, stainless steel such as SUS316 or a superelastic alloy such as a Ni—Ti alloy is provided in multiple layers. It can be reinforced by the coil body 6, and breakage of the lead wire 962 can be prevented. In addition, by storing the lead wire 962 in the gap 25g of the second winding 25w, the space can be effectively used, and the bulkiness of the guide wire G2 can be suppressed.

In addition, the present invention is not limited to the configuration of the above-described embodiment, but is indicated by the scope of the claims, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims. be done. For example, part of the configurations of the above-described embodiments may be deleted or replaced with other configurations, or other configurations may be added to the configurations of the above-described embodiments.

For example, in the above-described embodiment, a single wire having a rectangular outermost contour in cross section is used as the second winding, and the second winding is wound in a single or multiple windings. A multi-layer coil body comprising coil layers has been described. However, in the second coil layer 27, the contour shape of the second winding 27w may be a shape other than a rectangular shape, such as a circular single wire 271w (see FIG. 10).

Further, in the above-described embodiment, a multilayer coil body having a second coil layer using a single wire as the second winding has been described. However, the second coil layer may consist of windings that include twisted wires as the second winding. In such a case, the cross-sectional shape of the wire (single wire) constituting the stranded wire may be a rectangular shape, a shape other than a rectangular shape (such as a circular shape), or a mixture of these. may be Further, the second winding constituting the second coil layer may be formed so that the contour shape of the outermost periphery in the cross section of the wire as a whole is substantially rectangular.

Also, in the above-described embodiment, a multilayer coil body made up of three layers (first coil layer, second coil layer, and third coil layer) has been described. However, the multilayer coil body may be provided with a second coil layer between the first coil layer and the third coil layer. For example, it may be a multilayer coil body having another coil layer inside the first coil layer, or a multilayer coil body having another coil layer outside the third coil layer. good too.

1, 2, 3, 4, 5, 6 multilayer coil body 11 first coil layer 11w first winding 21, 22, 23, 24, 25, 27 second coil layer 21w, 22w, 23w, 24w, 25w, 27w, second winding 21g, 22g, 23g, 24, 25g gap 31, A31, 36 third coil layer 31w, A31w, 36w third winding C catheter G1, G2 guide wire

Claims (5)

a hollow first coil layer in which the first winding is spirally wound;
a third coil layer provided to cover the first coil layer and having a third winding spirally wound thereon;
a second coil layer provided adjacent to between the first coil layer and the third coil layer and having a second coil wound spirally thereon. being a body,
at least one winding forming the second coil layer has a larger cross-sectional area than at least one winding forming the first coil layer and the third coil layer;
A multilayer coil body, wherein a gap is formed between at least some of the second windings adjacent to each other in the longitudinal direction. 2. The multi-layer coil body according to claim 1, wherein the contour shape of the outermost periphery in the cross section of said second winding is substantially rectangular. 3. The multilayer coil body according to claim 1, wherein the gap formed between the second windings includes two or more gaps having different lengths in the longitudinal direction. 4. The multilayer coil assembly of claim 3, wherein said second winding comprises a radiopaque material. The multilayer coil body according to any one of claims 1 to 4, wherein a conductor is provided in the gap formed between the second windings.

Images