JP6739776B1 - Embolic coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an embolic coil which is hard to buckle and can be easily manufactured. An embolic coil (1) that can be introduced into an aneurysm (A) using a catheter (3) by winding a wire (2) in a direction in which a winding axis direction matches a length direction (Y) of the embolic coil (1). It has a portion in which the large-diameter coil portions 7 and the small-diameter coil portions 9 are alternately formed by making the winding diameter of the strand 2 different, and the winding diameter D1 of the large-diameter coil portion 7 is The embolic coil 1 is 12 times or less the wire diameter d of 2 and the winding diameter D2 of the small diameter coil portion 9 is 3 times or more the wire diameter d of the wire 2. [Selection diagram] Figure 2

Description

The present invention relates to embolic coils.

Conventionally, various treatment methods have been performed to treat an aneurysm. Among these, there is a treatment method in which an embolic coil is introduced into the aneurysm using a catheter to suppress blood in the blood vessel from entering the aneurysm. In such a treatment method, a linear embolic coil is generally used, but it is possible to fill the aneurysm with a high filling rate, and it is easy to suppress the burden on the aneurysm ( That is, an embolic coil that can be filled into an aneurysm with high operability is desired. Therefore, various shapes of embolic coils have been disclosed.
For example, in Patent Document 1, a portion is formed by winding a wire, and a large-diameter coil portion having a large diameter and a small-diameter coil portion having a small diameter are alternately formed by changing winding diameters of the wire. An embolic coil having is disclosed.

JP, 2008-50760, A

However, an embolic coil having a portion in which a large-diameter coil portion and a small-diameter coil portion are alternately formed by winding a strand wire and making the winding diameter of the strand wire different is used as an embolic coil. When the embolic coil is introduced into the aneurysm, the embolic coil may buckle due to the small-diameter coil part getting into the large-diameter coil part as the embolic coil is pushed or pulled in the catheter. there were. Further, it is difficult to manufacture the embolic coil depending on the winding method of the wire.

Therefore, an object of the present invention is to provide an embolic coil that is hard to buckle and can be manufactured reliably.

The embolic coil according to the first aspect of the present invention for solving the above-mentioned problems is an embolic coil that can be introduced into an aneurysm by using a catheter, and the winding axis direction matches the length direction of the embolic coil. It is configured by winding a wire in the direction of, and by having different winding diameters of the wire, it has a portion in which a large-diameter coil portion and a small-diameter coil portion are formed alternately, The winding diameter is 12 times or less the wire diameter of the element wire, and the winding diameter of the small-diameter coil portion is 3 times or more the wire diameter of the element wire.

According to this aspect, the winding diameter of the large-diameter coil portion is 12 times or less the wire diameter of the wire. If the winding diameter of the large-diameter coil portion is too large, buckling tends to occur. However, by setting the winding diameter of the large-diameter coil portion to 12 times or less the wire diameter of the strand, it is possible to obtain an embolic coil that is difficult to buckle. The winding diameter of the small-diameter coil portion is three times or more the wire diameter of the wire. If the winding diameter of the small-diameter coil portion is too small, it becomes difficult to manufacture the embolic coil. However, if the winding diameter of the small-diameter coil portion is set to 3 times or more the wire diameter of the strand, it becomes difficult to manufacture the embolization coil. Can be suppressed. That is, by setting the winding diameter of the large-diameter coil portion to be 12 times or less the wire diameter of the strand and the winding diameter of the small-diameter coil portion to be 3 times or more the wire diameter of the strand, it is possible to securely manufacture the embolus without buckling. A coil can be provided.

An embolic coil according to a second aspect of the present invention is the embolic coil according to the first aspect, wherein the strands are wound without a gap in the length direction and are adjacent to each other when the embolic coil is pulled in the length direction. The initial tension, which is a force that creates a gap between the strands, is 0.001 N or more.

According to this aspect, the initial tension is 0.001 N or more. By setting the initial tension to 0.001 N or more, it is possible to improve straightness when introducing the embolic coil using the catheter.

An embolic coil according to a third aspect of the present invention is the embolic coil according to the first or second aspect, wherein the length of the small diameter coil portion in the length direction is 0.2 times or more the winding diameter of the large diameter coil portion. Is characterized in that

According to this aspect, the length in the length direction of the small-diameter coil portion is 0.2 times or more the winding diameter of the large-diameter coil portion. By setting the length of the small-diameter coil portion in the length direction to be 0.2 times or more the length of the large-diameter coil portion in the length direction, the large-diameter coil portion easily gets caught in the small-diameter coil portion in the aneurysm, The embolic coil introduced into the aneurysm can be easily maintained in a block shape.

An embolic coil according to a fourth aspect of the present invention is characterized in that, in the aspect of any one of the first to third aspects, the length of the small-diameter coil portion in the length direction is 50 mm or less. ..

According to this aspect, the length of the small-diameter coil portion in the length direction is 50 mm or less. If the length of the small-diameter coil portion is too long, it will be difficult to adjust the embolic coil into a mass of appropriate size within the aneurysm, but the length of the small-diameter coil portion will be 50 mm. By doing the following, the embolic coil can be easily adjusted to an appropriate size within the aneurysm.

An embolic coil according to a fifth aspect of the present invention is the embolic coil according to any one of the first to fourth aspects, wherein the large-diameter coil portion has at least 50% of the strands adjacent to each other when viewed in the length direction. It is characterized in that the strands are wound so as to overlap each other as described above.

According to this aspect, the large-diameter coil portion is formed by winding the strands of wire, which are adjacent to each other when viewed in the length direction, at least 50% or more overlapping each other. Adjacent wires are overlapped by at least 50% or more when viewed in the length direction, so that when the embolic coil is introduced into an aneurysm using a catheter, the embolic coil is pushed in the catheter. Even if it is pulled or pulled, it is possible to prevent the embolic coil from buckling due to interference between adjacent wires.

An embolic coil according to a sixth aspect of the present invention is the embolic coil according to the fifth aspect, wherein the large-diameter coil portion overlaps between the strands adjacent to each other from the end portion side toward the central portion side in the length direction. It is characterized in that it has a region where the amount of overlap is small.

According to this aspect, the large-diameter coil portion has a region in which the amount of overlap between the adjacent wires becomes smaller from the end side toward the center side in the length direction. The embolic coil is likely to buckle in a portion of the large-diameter coil portion adjacent to the small-diameter coil portion, but buckling of the portion can be effectively suppressed by increasing the amount of overlap between adjacent strands of the portion. The buckling of the embolic coil can be effectively suppressed.

An embolic coil according to a seventh aspect of the present invention is the embolic coil according to the fifth or sixth aspect, wherein the large-diameter coil portion has the same winding diameter in the portion where the winding diameter of the wire is maximum. The strand is wound a plurality of times with the same winding diameter so that

According to this aspect, in the large-diameter coil portion, the wire is wound a plurality of times with the same winding diameter so that the adjacent wires have the same winding diameter in the portion where the winding diameter of the wire is maximum. That is, at the portion where the winding diameter that is most likely to buckle is the maximum, the amount of overlap between the adjacent wires is 100%. Therefore, the buckling of the embolic coil can be suppressed particularly effectively.

An embolic coil according to an eighth aspect of the present invention is the embolic coil according to the seventh aspect, wherein the large-diameter coil portion has a maximum winding diameter of the wire in the lengthwise direction with respect to the entire large-diameter coil portion. It is characterized in that the ratio is 2/5 or more and 4/5 or less.

According to this aspect, in the large-diameter coil portion, the ratio of the portion having the largest winding diameter of the wire to the entire large-diameter coil portion is 2/5 or more and 4/5 or less. With such a structure, the straightness of the embolic coil when moving in the catheter is improved, and a large-diameter coil portion that is hard to buckle and has a large winding diameter can be formed.

An embolic coil according to a ninth aspect of the present invention is the embolus coil according to any one of the fifth to eighth aspects, wherein the large-diameter coil portion has an average of the strands adjacent to each other when viewed from the length direction. It is characterized in that it is formed by winding the strands of wire with an overlap of 75% or more.

According to this aspect, the wires adjacent to each other in the lengthwise direction overlap each other on average by 75% or more, so that the buckling of the large-diameter coil portion can be suppressed and the wires can move inside the catheter. At this time, it is possible to suppress the deformation of the embolic coil to disperse the force, that is, the reduction in workability when introducing the embolic coil into the catheter.

The embolic coil according to a tenth aspect of the present invention is the embolus coil according to any one of the fifth to ninth aspects, wherein the large-diameter coil portion has 60% or more of the strands adjacent to each other when viewed from the length direction. It is characterized in that the strands are wound to overlap each other by 85% or less.

According to this aspect, since the strands adjacent to each other when viewed in the length direction overlap by 60% or more, the buckling of the embolic coil can be suppressed particularly effectively, and the strands adjacent to each other when viewed in the length direction are adjacent to each other. Since the wires are overlapped with each other by 85% or less, the anchor effect due to the catch of the large-diameter coil portion can be enhanced.

An embolic coil according to an eleventh aspect of the present invention is the embolic coil according to any one of the first to fourth aspects, wherein the large-diameter coil portion is adjacent to the element when viewed from a cross direction intersecting the length direction. It is characterized in that the element wire is wound so that the angle formed by the wires with respect to the length direction is at least 30° or less.

According to this aspect, in the large-diameter coil portion, the strands are wound such that the angle with respect to the length direction formed between the adjacent strands when viewed from the intersecting direction is at least 30° or less. Is configured. When the embolic coil is introduced into the aneurysm using a catheter, the angle with respect to the length direction formed by adjacent strands when viewed from the cross direction is at least 30° or less, Even when the embolic coil is pushed or pulled in the catheter, it is possible to prevent the embolic coil from buckling due to interference between adjacent wires.

It is an explanatory view showing the outline of catheter treatment using an embolic coil. It is a side view which shows the primary shape of the embolus coil which concerns on Embodiment 1 of this invention. It is a side view which shows the secondary shape of the embolic coil which concerns on Embodiment 1 of this invention. It is an embolic coil which concerns on Embodiment 1 of this invention, Comprising: It is a figure which shows the embolic coil before the start of introduction. It is an embolic coil which concerns on Embodiment 1 of this invention, Comprising: It is a figure explaining frame formation. It is a schematic side sectional view showing a detailed shape of a part of a large-diameter coil portion of the embolic coil according to the first embodiment of the present invention. It is a schematic side cross-sectional view showing the detailed shape of a part of large diameter coil part of the embolic coil which concerns on Embodiment 2 of this invention.

The embolic coil 1 according to the embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

[First Embodiment] (see FIGS. 1 to 6)
First, an outline of catheter treatment using the embolic coil 1 will be described with reference to FIG.

The embolic coil 1 is used in the treatment of an aneurysm using the catheter 3 for the purpose of preventing the rupture of the aneurysm A. Specifically, for example, when an aneurysm A develops at a bifurcation C of a cerebral artery B of the human body H, an insertion opening F for inserting the catheter 3 into the base E of the foot is provided as shown in FIG. After opening, a catheter 3 having a diameter of about 2 mm is inserted from the femoral artery at the base E of the foot.

Further, a contrast medium is injected into the blood vessel, and the catheter 3 is guided to a position slightly inside the aneurysm A at the site where the aneurysm A is occurring while observing a fluoroscopic image by X-ray. Then, the embolic coil 1 of the present invention is inserted into the catheter 3, guided along the inner wall of the catheter 3 to the tip of the catheter 3, pushed out from the opening of the tip, and the tip of the embolic coil 1 is inserted into the aneurysm A. Reach Hereinafter, the embolic coil 1 is pushed out to introduce the embolic coil 1 into the aneurysm A and fill it. Aneurysms include a saccular aneurysm and a dissecting aneurysm that can be formed in a non-branching part other than the branching part C, and these aneurysms can be treated by the embolic coil 1.

Next, a specific configuration of the embolic coil 1A according to the first embodiment of the present invention will be described based on FIGS. 2 and 3.

The embolic coil 1A of the present embodiment is formed by spirally winding a wire 2, and has a large diameter large-diameter coil portion 7 wound as a maximum outer diameter D1 and an outer diameter smaller than the large-diameter coil portion 7. A plurality of small-diameter coil portions 9 wound with a diameter D2 are arranged alternately in the longitudinal direction Y of the embolic coil 1. The embolic coil 1A has an uneven structure based on the fact that a plurality of large-diameter coil portions 7 and a plurality of small-diameter coil portions 9 are alternately present on the surface. Although not provided in the embolic coil 1 of the present embodiment, it may have a cylindrical structure with a flat surface wound with a uniform diameter. The detailed structure of the large-diameter coil portion 7, which is a main portion of the embolic coil 1A of the present embodiment, will be described later.

As the material of the embolic coil 1A, a wire made of platinum, tungsten, or stainless steel having a wire diameter d of the wire 2 of 15 μm to 100 μm, preferably 30 μm to 75 μm can be applied as an example. Since these materials are resistant to corrosion and have both appropriate straightness and flexibility, when the embolic coil 1A moves inside the catheter 3, the embolic coil 1A moves smoothly while maintaining appropriate straightness, and the embolic coil 1A moves smoothly. When the coil 1A is introduced into the aneurysm A, the coil 1A exhibits its flexibility and is smoothly curved and filled.

The outer diameter D2 of the small-diameter coil portion 9 may be 0.06 mm to 0.40 mm, preferably 0.12 mm to 0.30 mm. The maximum outer diameter D1 of the large-diameter coil portion 7 is larger than the outer diameter D2 of the small-diameter coil portion 9 and is a range in which smooth movement is possible within the catheter 3, for example, 0.2 mm to 0.5 mm, preferably It can be set to 0.25 mm to 0.47 mm.

As described above, the embolic coil 1A of the present embodiment is the embolic coil 1 that can be introduced into the aneurysm A using the catheter 3, and the winding axis direction is the longitudinal direction of the embolic coil 1A. It is configured by winding the wire 2 in a direction coinciding with the longitudinal direction Y of the wire 1. The embolic coil 1A of this embodiment has a portion in which the large-diameter coil portions 7 and the small-diameter coil portions 9 are alternately formed by changing the winding diameter of the wire 2.
Here, the maximum outer diameter D1 as the winding diameter of the large-diameter coil portion 7 is preferably 12 times or less the wire diameter d of the wire 2. If the winding diameter of the large-diameter coil portion 7 is too large, it will easily buckle. However, by setting the winding diameter of the large-diameter coil portion 7 to 12 times or less the wire diameter d of the wire 2, the embolic coil 1 that is hard to buckle is obtained. This is because it is possible. The outer diameter D2, which is the winding diameter of the small-diameter coil portion 9, is preferably three times or more the wire diameter d of the wire 2. If the winding diameter of the small-diameter coil portion 9 is too small, it is difficult to manufacture the embolic coil 1. However, by setting the winding diameter of the small-diameter coil portion 9 to be three times or more the wire diameter d of the wire 2, This is because it is possible to suppress difficulty in manufacturing. That is, the maximum outer diameter D1 of the large-diameter coil portion 7 is 12 times or less the wire diameter d of the wire 2, and the outer diameter D2 of the small-diameter coil portion 9 is 3 times or more the wire diameter d of the wire 2. It is possible to provide the embolic coil 1 which is hard to buckle and can be easily manufactured. In the embolic coil 1A of this embodiment, the maximum outer diameter D1 of the large-diameter coil portion 7 is 12 times or less the wire diameter d of the wire 2, and the outer diameter D2 of the small-diameter coil portion 9 is the wire 2 It is three times or more the wire diameter d.
In particular, it is preferable that the maximum outer diameter D1 of the large-diameter coil portion 7 is 9 times or less the wire diameter d of the wire 2, and the outer diameter D2 of the small-diameter coil portion 9 is 3 of the wire diameter d of the wire 2. It is preferably at least 5 times. When the maximum outer diameter D1 of the large-diameter coil portion 7 is 9 times or less of the wire diameter d of the wire 2, there is an advantage that the shape stability during manufacturing is easily ensured, and the outer diameter D2 of the small-diameter coil portion 9 is This is because, even when the wire diameter d of the wire 2 is 3.5 times or more, there is an advantage that the shape stability during manufacturing can be easily secured.

In the embolic coil 1A of the present embodiment, as shown in FIG. 2, the wire 2 is wound in the longitudinal direction Y without any gap. When the embolic coil 1 having such a configuration is used, the initial tension, which is a force that generates a gap between the adjacent wires 2 when the embolic coil 1 is pulled in the longitudinal direction Y, is 0.001 N or more. preferable. This is because setting the initial tension to 0.001 N or more can improve the straightness when the embolic coil 1 is introduced using the catheter 3. The embolic coil 1A of the present embodiment has an initial tension of 0.002N, which is 0.001N or more.

Further, although FIG. 2 shows the embolic coil 1A having a primary shape when moving in the catheter 3, it facilitates the formation of the frame 23 according to the size and shape of the aneurysm A as shown in FIG. Therefore, a secondary shape having a larger coil diameter (for example, 3 mm to 30 mm) may be formed in advance. The formation of the secondary shape may be omitted, and it has been confirmed that the embolic coil 1A of the present embodiment can smoothly form the frame 23 without forming the secondary shape.

Next, a process of introducing the embolic coil 1A into the aneurysm A using the embolic coil 1A will be described with reference to FIGS. 4 to 5. In detail, the step of introducing the embolic coil 1A into the aneurysm A using the embolic coil 1A according to the present embodiment includes (A) immediately before the introduction is started, and (B) two steps of forming the frame 23. I will explain separately.

(A) Immediately before the start of introduction (see Fig. 4)
When the embolic coil 1A is introduced, first, the catheter 3 is placed on the human body H so that the tip of the catheter 3 reaches the inside of the aneurysm A. Next, the distal end Y1 side end 17 of the distal end direction Y1 and the rear end direction Y2 in the longitudinal direction Y of the embolic coil 1 is inserted into the installed catheter 3 from the outside, and is fitted to the inner wall surface of the catheter 3. To move the embolic coil 1A toward the aneurysm A.

At this time, in the embolic coil 1A of the present embodiment, since the end portion 17 of the large-diameter coil portion 7 to be inserted first is formed by the spherical convex curved surface, the insertion of the embolic coil 1A into the catheter 3 is smooth. Can be done. Further, since the large-diameter coil portions 7 of the embolic coil 1A of the present embodiment have the same outer diameter, the outer circumference thereof functions as a guide, and the straightness of the embolic coil 1A within the catheter 3 can be maintained. it can. As a result, the embolic coil 1A can be moved smoothly. Then, if the end portion 17 of the embolic coil 1A is projected from the distal end opening portion of the catheter 3 to enter the aneurysm A, the preparatory work prior to the introduction of the embolic coil 1A is completed.

(B) Formation of frame 23 (see FIG. 5)
After completion of the preparatory work, the embolic coil 1A is introduced, and the embolic coil 1A is pushed into the catheter 3. The embolic coil 1A sent out from the distal end opening of the catheter 3 is introduced deep inside the aneurysm A, and the end portion 17 of the embolic coil 1A first comes into contact with the inner wall surface of the aneurysm A on the inner side while being curved. It is fed toward the front or side.

Then, the end portion 17 of the embolic coil 1A that is extended toward the front side or the side side comes into contact with the inner surface of the aneurysm A and is folded back in a curved state to form a ring-shaped portion 21. Further, as the introduction of the embolic coil 1A progresses, a plurality of ring-shaped portions 21 are formed as shown in FIG. 5, and the outer shell for introducing the subsequent embolic coil 1A is formed by the plurality of ring-shaped portions 21. The frame 23 as a member is formed. Here, the abundances of the large-diameter coil portion 7 and the small-diameter coil portion 9 in the plurality of ring-shaped portions 21 forming the frame 23 are preferably set and used as appropriate for the size and shape of the aneurysm A.

The large-diameter coil portion is formed on the frame 23 at the contact position (intersection position) between the ring-shaped portions 21 when the frame 23 is formed, due to the presence of the uneven structure including the large-diameter coil portion 7 and the small-diameter coil portion 9. There is a part where 7 is caught. As a result, an anchor effect is generated due to the catching of the large-diameter coil section 7, and the anchor effect stabilizes the structure of the frame 23, that is, the three-dimensional structure of the plurality of ring-shaped portions 21.

Here, the length Ls (see FIG. 2) of the small-diameter coil portion 9 in the longitudinal direction Y is preferably 0.2 times or more of the maximum outer diameter D1 as the winding diameter of the large-diameter coil portion 7. By setting the length Ls of the small-diameter coil portion 9 in the longitudinal direction Y to be 0.2 times or more of the maximum outer diameter D1 of the large-diameter coil portion 7, when forming the frame 23 in the aneurysm A, the large-diameter coil portion is formed. This is because 7 is likely to be caught in the small-diameter coil portion 9 and the anchor effect is enhanced, so that the embolic coil 1 introduced into the aneurysm A can be easily maintained in a lump shape. In the embolic coil 1A of this embodiment, the length Ls of the small-diameter coil portion 9 in the longitudinal direction Y is 0.2 times or more the maximum outer diameter D1 of the large-diameter coil portion 7.

Further, the length Ls of the small-diameter coil portion 9 in the longitudinal direction Y is preferably 50 mm or less. If the length Ls of the small-diameter coil portion 9 in the longitudinal direction Y is made too long, when the frame 23 is formed in the aneurysm A, the frame 23 formed by the embolic coil 1 should be adjusted to a lump having an appropriate size. However, by setting the length Ls of the small-diameter coil portion 9 in the longitudinal direction Y to 50 mm or less, the frame 23 formed of the embolic coil 1 can be easily adjusted to an appropriate size in the aneurysm A. This is because it is possible. In the embolic coil 1A of this embodiment, the length Ls of the small-diameter coil portion 9 in the longitudinal direction Y is 50 mm or less.

Next, the details of the large-diameter coil portion 7A of the embolic coil 1A of the present embodiment will be described with reference to FIG.

As shown in FIG. 6, the large-diameter coil portion 7A of the present embodiment has a cross-section that is a linear slope with respect to the longitudinal direction Y of the embolic coil 1 in both the front end direction Y1 and the rear end direction Y2. It has a slope 72. In addition, the large-diameter coil portion 7A of the present embodiment has a parallel portion 71 having a linear cross section at a position sandwiched by the inclined surface portions 72 in the front end direction Y1 and the rear end direction Y2. have. The position of the parallel portion 71 is the position where the maximum outer diameter D1 is obtained.

Here, the large-diameter coil portion 7A of the present embodiment is configured by winding the wire 2 such that the wire 2 adjacent to each other when viewed in the longitudinal direction Y of the embolic coil 1 overlaps each other by at least 50% or more. There is. Specifically, in the large-diameter coil portion 7A of the present embodiment, adjacent strands 2 overlap each other by 50% when viewed in the longitudinal direction Y in the slope portion 72, and in the parallel portion 71 when viewed in the longitudinal direction Y. The adjacent two wires 2 are 100% overlapped with each other.

As described above, in the embolic coil 1A of the present embodiment, the large-diameter coil portion 7 is wound by winding the wire 2 such that the wire 2 adjacent to each other when viewed from the longitudinal direction Y of the embolic coil 1 overlaps at least 50% or more. It is constructed and constructed. With such a structure, when the embolic coil 1A is introduced into the aneurysm A using the catheter 3, the embolic coil 1A may be pushed or pulled in the catheter 3. Also, it is possible to prevent the embroidery coil from buckling due to interference between the adjacent wires 2.

Here, it is particularly preferable from the viewpoint of suppressing buckling of the embolic coil that the strands 2 adjacent to each other when viewed in the longitudinal direction Y overlap at least 60% or more. However, from the viewpoint of enhancing the anchor effect, it is preferable that the adjacent wires 2 do not overlap each other by more than 85% when viewed in the longitudinal direction Y.

It should be noted that "the large-diameter coil portion 7 is formed by winding the wires 2 such that the wires 2 adjacent to each other when viewed in the longitudinal direction Y of the embolic coil 1 overlap at least 50% or more." All the adjacent wires 2 forming the large-diameter coil portion 7, and the adjoining portion 73 between the wire 2 forming the large-diameter coil portion 7 and the wire 2 forming the small-diameter coil portion 9 (see FIG. 6 ). In the above, it means that the strands 2 are wound so as to overlap at least 50% or more when viewed from the longitudinal direction Y of the embolic coil 1.

In other words, the large-diameter coil portion 7A of the present embodiment is formed by the adjacent wires 2 when viewed from the intersecting direction intersecting the longitudinal direction Y of the embolic coil 1 as shown in FIG. The wire 2 is wound so that the angle Θ of the embolic coil 1 to the longitudinal direction Y is at least 30° or less. Specifically, in the large-diameter coil portion 7A of the present embodiment, the angle Θ with respect to the longitudinal direction Y of the embolic coil 1 formed by the adjacent wires 2 in the slope portion 72 is 30°. In the parallel portion 71, the angle Θ with respect to the longitudinal direction Y of the embolic coil 1 formed by the adjacent wires 2 is 0°.

Thus, in the embolic coil 1A of this embodiment, the angle with respect to the longitudinal direction Y of the embolic coil 1 formed by the adjacent wires 2 when the large-diameter coil portion 7 is viewed from the intersecting direction is at least 30° or less. The wire 2 is wound to form an angle of. With such a structure, when the embolic coil 1A is introduced into the aneurysm A using the catheter 3, the embolic coil 1A may be pushed or pulled in the catheter 3. Also, it is possible to prevent the embolic coil 1A from buckling due to interference between the adjacent wires 2.

In addition, "when the large-diameter coil portion 7 is viewed from the crossing direction, the embroidery coil 1 formed by the adjacent wire 2 has an angle of at least 30° or less with respect to the longitudinal direction Y of the embolic coil 1. Is formed by being wound." means that all the adjacent wires 2 that form the large-diameter coil portion 7 and the wires 2 that form the large-diameter coil portion 7 and the small-diameter coil portion 9 are formed. In the portion 73 adjacent to the wire 2, the wire 2 is formed so that the angle with respect to the longitudinal direction Y of the embolic coil 1 formed by the wire 2 adjacent to each other when viewed from the crossing direction is at least 30° or less. Means that it is rolled up.

Further, as shown in FIG. 6, in the large-diameter coil portion 7A of the present embodiment, in the parallel portion 71 which is the portion where the winding diameter of the wire 2 is the maximum, the adjacent wire 2 has the same winding diameter. The wire 2 is wound multiple times with the same winding diameter. That is, the large-diameter coil portion 7A of the present embodiment is a portion where the winding diameter that is most likely to buckle is the maximum, and the overlap amount between the adjacent wires 2 viewed from the longitudinal direction Y of the embolic coil 1 is set to 100%. There is. For this reason, the large-diameter coil portion 7A of the present embodiment has a structure capable of suppressing the buckling of the embolic coil 1 particularly effectively.

Since FIG. 6 is a schematic diagram, it does not necessarily represent the actual shape of the large-diameter coil portion 7A of the present embodiment, but the large-diameter coil portion 7A of the present embodiment does not correspond to the embolic coil 1. L1/L2, which is the ratio of the length L1 of the parallel portion 71, which is the maximum winding diameter of the wire 2 in the longitudinal direction Y, to the overall length L2 of the large-diameter coil portion 7, is 2/25 or more 5 It is less than four minutes. When L1/L2 is equal to or more than 2/25, the parallel portion 71 easily follows the inner wall of the catheter 3 when moving in the catheter 3, and the straightness of the embolic coil 1 is improved. Further, since L1/L2 is not more than ⅕, buckling does not easily occur even if the winding diameter of the large-diameter coil portion 7A is increased, and the anchor effect can be enhanced. As described above, the large-diameter coil portion 7A according to the present embodiment has such a configuration, so that the straightness of the embolic coil 1 when moving in the catheter 3 is improved, and the large-diameter coil portion 7A is difficult to buckle and has a large winding. A large-diameter coil portion 7 having a diameter is formed.

Here, in the large-diameter coil portion 7A, it is particularly preferable that the wires 2 adjacent to each other when viewed in the longitudinal direction Y overlap each other by 75% or more on average, and the wires 2 are wound. Since the adjacent wires 2 overlap each other on average in the longitudinal direction Y by 75% or more, not only can buckling of the large-diameter coil portion 7 be suppressed, but also embolization during movement in the catheter 3 This is because the coil 1 is deformed to disperse the force, that is, it is possible to suppress deterioration in workability when the embolic coil 1 is introduced into the catheter 3.

[Second Embodiment] (FIG. 7)
Next, the embolic coil 1 according to the second embodiment will be described in detail with reference to FIG. 7.
FIG. 7 is a diagram corresponding to FIG. 6 of the embolic coil 1A of the first embodiment. In addition, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.
The embolic coil 1 of the present embodiment has the same configuration as the embolic coil 1A of the first embodiment, except for the configuration of the slope portion 72 of the large-diameter coil portion 7.

As shown in FIG. 7, the slope portion 72 of the large-diameter coil portion 7B, which is the large-diameter coil portion 7 of the embolic coil 1 according to the second embodiment, includes the end portion side in the longitudinal direction Y of the embolic coil 1 from the central portion side. The amount of overlap between the adjacent wires 2 becomes smaller as it goes to. In other words, as shown in FIG. 7, the sloped portion 72 of the large-diameter coil portion 7B is arranged so that the adjacent strands 2 extend from the center side toward the end side in the longitudinal direction Y of the embolic coil 1. The positional relationship between them is almost parallel to the longitudinal direction Y. As described above, it is preferable that the large-diameter coil portion 7 has a region in which the amount of overlap between the adjacent strands becomes smaller from the end portion side toward the central portion side in the longitudinal direction Y of the embolic coil 1. The embolic coil 1 is likely to buckle in a portion of the large-diameter coil portion 7 adjacent to the small-diameter coil portion 9, but the buckling of the portion is effective by increasing the overlapping amount between the adjacent strands 2 of the portion. This is because the buckling of the embolic coil 1 can be effectively suppressed.

In the large-diameter coil portion 7A of the first embodiment, the maximum outer diameter D1 as the winding diameter of the large-diameter coil portion 7 is 12 times or less the wire diameter d of the wire 2, and the large-diameter coil portion 9 Although the outer diameter D2, which is the winding diameter, is three times or more the wire diameter d of the strand 2, the same applies to the large-diameter coil portion 7B of the present embodiment. Further, in the large-diameter coil portion 7B of the present embodiment as well, as in the large-diameter coil portion 7A of the first embodiment, when viewed from the longitudinal direction Y of the embolic coil 1, any adjacent strands 2 are over at least 50% or more. While being wrapped, the maximum angle Θmax, which is the maximum angle of the embolic coil 1 formed by any adjacent strands 2 with respect to the longitudinal direction Y, is at least 30° or less.

The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the invention described in the claims, and it goes without saying that they are also included in the scope of the present invention.
Further, by using the catheter 3 that can use the embolic coil 1 of the above-described embodiment, it becomes possible to fill the embolism coil 1 into the aneurysm A while suppressing the buckling of the embolism coil 1.

1... Embolic coil, 1A... Embolic coil, 2... Strand, 3... Catheter, 7... Large diameter coil part,
7A...Large diameter coil portion, 7B...Large diameter coil portion, 9...Small diameter coil portion, 17...End portion,
21... Ring-shaped part, 23... Frame, 71... Parallel part, 72... Slope part,
73... Adjacent part, A... Aneurysm, B... Cerebral artery, C... Bifurcation, d... Wire diameter of strand 2,
D1... maximum outer diameter, D2... outer diameter, E... foot base, F... insertion opening, H... human body,
L1... the length of the parallel portion 71, L2... the overall length of the large-diameter coil portion 7,
Ls: Length in the length direction of the small diameter coil

Claims (9)

An embolic coil that can be introduced into an aneurysm using a catheter,
It is configured by winding a wire in a direction in which the winding axis direction matches the length direction of the embolic coil,
By changing the winding diameter of the wire, the small-diameter coil portion having a uniform winding diameter, the maximum portion having the maximum winding diameter, and the winding diameter transitioning from the winding diameter of the small-diameter coil portion to the winding diameter of the maximum portion. A large-diameter coil portion having an inclined surface portion and
The slope portion has a portion in which the amount of overlap between the adjacent strands becomes smaller from the end portion side in the length direction toward the central portion side,
The winding diameter of the large-diameter coil portion is 12 times or less the wire diameter of the strand,
Winding diameter of the small-diameter coil section state, and are more than three times the wire diameter of the wire,
The embolic coil, wherein the large-diameter coil portion is formed by winding the strands of wire so that the strands of wire adjacent to each other when viewed in the lengthwise direction overlap each other by at least 50% or more . An embolic coil that can be introduced into an aneurysm using a catheter,
It is configured by winding a wire in a direction in which the winding axis direction matches the length direction of the embolic coil,
By changing the winding diameter of the wire, the small-diameter coil portion having a uniform winding diameter, the maximum portion having the maximum winding diameter, and the winding diameter transitioning from the winding diameter of the small-diameter coil portion to the winding diameter of the maximum portion. A large-diameter coil portion having an inclined surface portion and
The slope portion has a portion in which the amount of overlap between the adjacent strands becomes smaller from the end portion side in the length direction toward the central portion side,
The winding diameter of the large-diameter coil portion is 12 times or less the wire diameter of the strand,
Winding diameter of the small-diameter coil section state, and are more than three times the wire diameter of the wire,
The embolic coil , wherein the slanted surface portion is formed by winding the strands of wire so that the strands adjacent to each other when viewed in the lengthwise direction overlap each other by 60% or more and 85% or less . The embolic coil according to claim 2 ,
The embolic coil, wherein the large-diameter coil portion is formed by winding the strands of wire so that the strands of wire adjacent to each other when viewed in the lengthwise direction overlap each other by at least 50% or more. The embolic coil according to any one of claims 1 to 3 ,
The wire is wound without a gap in the length direction,
An embolic coil, wherein an initial tension, which is a force that generates a gap between adjacent strands when the embolic coil is pulled in the length direction, is 0.001 N or more. The embolic coil according to any one of claims 1 to 4 ,
The embolic coil, wherein the length of the small-diameter coil portion in the length direction is 0.2 times or more the winding diameter of the large-diameter coil portion. The embolic coil according to any one of claims 1 to 5 ,
The embolic coil, wherein the length of the small-diameter coil portion in the length direction is 50 mm or less. The embolic coil according to any one of claims 1 to 6 ,
The large-diameter coil portion is characterized in that the wire is wound a plurality of times with the same winding diameter so that the adjacent wires have the same winding diameter in a portion where the winding diameter of the wire is the maximum. Embolic coil to do. The embolic coil according to claim 7 ,
The large-diameter coil portion is characterized in that a ratio of a portion having a maximum winding diameter of the wire in the length direction to the entire large-diameter coil portion is 2/25 or more and 4/5 or less. Embolic coil. The embolic coil according to any one of claims 1 to 8 ,
The embolic coil, wherein the large-diameter coil portion is formed by winding the strands of wire which are adjacent to each other when viewed from the length direction and overlap each other on average by 75% or more. ..

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