JP7656474B2 - Stranded wire and internal retrieval mechanism including the stranded wire - Google Patents

Description

The present invention relates to a twisted wire formed by twisting multiple strands together, and an internal retrieval mechanism that uses the twisted wire and is used to remove substances from the body.

Various devices have been developed to remove substances from inside a patient's body. For example, Patent Document 1 describes a medical treatment tool that includes a tip 70 and a coil spring body 54 that is connected to the base end of the tip 70 and is formed by combining thick wire 54a and thin wire 54b and winding these multiple wires, and that removes substances from inside a patient's body by rotating the tip 70 and the coil spring body 54 (see Figure 16, etc.).

JP 2007-98120 A

However, the coil spring body 54 provided in the medical treatment tool described in Patent Document 1 is wound so that the centers of the thick wire 54a and the thin wire 54b are aligned in a straight line when viewed in vertical cross section, which causes a problem that the amount of the thick wire 54a protruding from the outer circumference of the thin wire 54b is small, and the amount of material removed per rotation of the coil spring 54 is small.

On the other hand, in order to increase the amount of material removed per rotation of the coil spring 54, it is possible to arrange the thick wire 54a so that it is slightly moved outward from the thin wire 54b, thereby increasing the amount by which the thick wire 54a protrudes from the thin wire 54b. However, in this case, there is a problem in that the thick wire 54a becomes more likely to slip outward from the thin wire 54b.

The present invention was made in response to the above-mentioned problems with the conventional technology, and aims to provide a coil spring (hereinafter referred to as "twisted wire") that can stably retrieve and transport an appropriate amount of material from a patient's body without the thick wire shifting from the thin wire when rotated, and an internal retrieval mechanism equipped with the twisted wire.

In order to solve the above-mentioned problems, the stranded wire of the first aspect of the present invention is characterized in that it is formed by stranding a plurality of first strands having a generally circular cross section and at least one second strand having an outer diameter larger than the first strands and also having a generally circular cross section, the second strand being configured to have at least one recess on the contact surface with the adjacent first strands , into a hollow tubular shape .

The second aspect of the present invention is characterized in that in the stranded wire of the first aspect, at least one of the second strands has two recesses where adjacent first strands abut in cross section.

In addition, a third aspect of the present invention is characterized in that, in the stranded wire of the first or second aspect, the at least one second wire has a recess that, when viewed in cross section, expands in diameter along the first wire toward the center of the hollow tubular shape.

In addition, the stranded wire of the fourth aspect of the present invention is characterized in that it is formed by stranding a plurality of first strands into the hollow tubular shape, and at least one second strand which protrudes radially outward from the first strands and has at least one line segment which is approximately parallel to the center line of the hollow tubular shape in cross section, and is configured to abut against an adjacent one of the first strands on the at least one line segment.

A fifth aspect of the present invention is characterized in that, in the stranded wire of the fourth aspect, at least one of the second wires has two line segments that are approximately parallel to the center line of the hollow tubular wire in a cross-sectional view, and abuts adjacent first wires on the two line segments.

The sixth aspect of the present invention is characterized in that in the stranded wire of the fourth or fifth aspect, the at least one second strand has a substantially square or rectangular cross section.

Furthermore, the intracorporeal retrieval mechanism of the seventh aspect of the present invention is characterized by comprising a long housing, a cutter rotatably connected to the tip of the housing, and a twisted wire of any one of the first to sixth aspects rotatably arranged within the housing and having a tip connected to the cutter.

According to the stranded wire of the first aspect of the present invention, a plurality of first wires having a generally circular cross section and at least one second wire having a larger outer diameter than the first wires and also having a generally circular cross section, the second wire being configured to have at least one recess on the contact surface with an adjacent first wire , are stranded into a hollow tubular shape. Therefore , even when the stranded wire is rotated, the second wire will not shift, and by rotating the stranded wire, an appropriate amount of substance can be stably recovered and transported from the patient's body.

Furthermore, according to the second aspect of the present invention, in the stranded wire of the first aspect, at least one second strand has two recesses where adjacent first strands abut in cross section, so that when the stranded wire is rotated, the second strand does not shift further, and by rotating the stranded wire, an appropriate amount of substance can be more stably collected and transported from the patient's body.

Furthermore, according to a third aspect of the present invention, in the stranded wire of the first or second aspect, at least one second wire has a recess that expands in diameter along the first wire toward the center of the hollow tubular shape in cross section, so that when the stranded wire is rotated, the second wire does not shift further, and by rotating the stranded wire, an appropriate amount of substance can be more stably recovered and transported from the patient's body.

Furthermore, according to the fourth aspect of the present invention, the stranded wire is formed by twisting a plurality of first wires and at least one second wire, which protrudes radially outward from the first wires and has at least one line segment that is approximately parallel to the center line of the hollow tube in cross section, and is configured to abut an adjacent first wire on the at least one line segment, into the hollow tube shape. Therefore, even when the stranded wire is rotated , the second wire will not shift, and by rotating the stranded wire, an appropriate amount of substance can be stably recovered and transported from the patient's body.

Furthermore, according to a fifth aspect of the present invention, in the stranded wire of the fourth aspect, at least one second strand has two line segments that are approximately parallel to the hollow tubular center line in a cross-sectional view and abuts adjacent first strands on the two line segments. Therefore, when the stranded wire is rotated, the second strands do not shift further, and by rotating the stranded wire, an appropriate amount of substance can be more stably recovered and transported from the patient's body.

Furthermore, according to the sixth aspect of the present invention, in the twisted wire of the fourth or fifth aspect, at least one second strand has a substantially square or rectangular cross section, so in addition to the effects of the twisted wire of the fourth or fifth aspect, it is possible to easily manufacture a twisted wire in which the second twisted wire does not shift.

Furthermore, according to the seventh aspect of the present invention, the intracorporeal retrieval mechanism includes a long housing, a cutter rotatably connected to the tip of the housing, and a twisted wire of any of the first to sixth aspects rotatably arranged within the housing and having a tip connected to the cutter, so that an appropriate amount of material can be stably retrieved and transported from within the patient's body.

FIG. 2 is an external view of the in vivo retrieval mechanism of the present invention. FIG. 2 is an explanatory diagram of the inside of part A in FIG. 1 . FIG. 2 is an enlarged view of a first embodiment of a stranded wire used in the intracorporeal retrieval mechanism of the present invention. This is a cross-sectional view taken along line B-B of FIG. FIG. 11 is a cross-sectional view of a second embodiment of a stranded wire for use in the intracorporeal retrieval system of the present invention. FIG. 13 is a cross-sectional view of a third embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention. FIG. 13 is a cross-sectional view of a fourth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention. FIG. 13 is a cross-sectional view of a fifth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention. FIG. 13 is a cross-sectional view of a sixth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention. FIG. 13 is a cross-sectional view of a seventh embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention. FIG. 13 is a cross-sectional view of an eighth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention. FIG. 13 is a cross-sectional view of a ninth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention. FIG. 23 is a cross-sectional view of a stranded wire according to a tenth embodiment for use in the intracorporeal retrieval mechanism of the present invention.

The following describes an embodiment of the present invention with reference to the drawings.

First Embodiment
First, a first embodiment of the present invention will be described.
FIG. 1 is an external view of the internal retrieval mechanism of the present invention, FIG. 2 is an explanatory diagram of the inside of part A in FIG. 1, FIG. 3 is an enlarged view of a twisted wire of a first embodiment used in the internal retrieval mechanism of the present invention, and FIG. 4 is a cross-sectional view taken along line B-B in FIG. 3.

Note that for the stranded wire described in this embodiment and the embodiments described below, the cross section of the actual strand cut at right angles to the axial direction of the stranded wire is slightly elliptical in the case of a strand with a circular cross section depending on the twist angle of the stranded wire, a strand with an annular sector shape in cross section is slightly deformed in the annular sector shape depending on the twist angle of the stranded wire, and a strand with a generally rectangular cross section is slightly deformed in the rectangular shape depending on the twist angle of the stranded wire. However, for convenience of explanation, the cross-sectional shapes of the strands that make up the stranded wire in Figures 4 to 13 are shown schematically, different from the cross-sectional shapes of the actual strands.

In other words, the strands constituting the strands shown in Figures 4 to 8 are described as strands with a circular cross section cut at right angles to the twist angle of the strands, the strands constituting the strands shown in Figures 9, 12, and 13 are described as strands with an annular sector cross section cut at right angles to the twist angle of the strands, and the strands constituting the strands shown in Figures 10 and 11 are described as strands with a roughly rectangular cross section cut at right angles to the twist angle of the strands.

As shown in FIG. 1, the internal retrieval mechanism 100 of this embodiment for removing internal substances such as plaque from the body is composed of a catheter 3 (corresponding to the "housing" of the present invention) made of a long hollow tubular body, a cutter assembly 4 connected to the tip of the catheter 3, a gripping portion 6 connected to the base end of the catheter 3, and a motor 8 connected to the base end of the gripping portion 6.

The cutter assembly 4 comprises a cover body 4b connected to the tip of the catheter 3 and having multiple openings 4a, and a cutter 4c disposed inside the cover body 4b. The cutter 4c is connected to the tip of the stranded wire 1 (see Figure 2) described below, and can rotate with the rotation of the motor 8.

Therefore, the cutter assembly 4 cuts the internal body material D (see FIG. 2) such as plaque that has entered through the opening 4a of the cover body 4b with the rotating cutter 4c, and takes it inside the cutter assembly 4.

The gripping portion 6 is connected to the base end of the catheter 3 and is composed of a gripping portion main body 6a and a U-shaped gripping portion side body 6b connected to the gripping portion main body 6a. In addition, a gap S is formed in the gripping portion 6 between the gripping portion main body 6a and the gripping portion side body 6b so that the operator can grasp it.

Motor 8 has its body connected to the base end of gripper 6, and the rotating shaft of motor 8 is connected to the base end of twisted wire 1 (see Figure 2) described below.

In Figures 1 and 2, the cutter assembly 4 is connected linearly to the catheter 3, but although the mechanism is not shown, in reality, the cutter assembly 4 can be bent 360 degrees in all directions relative to the longitudinal axis of the catheter 3 by operating the gripping portion 6.

The catheter 3 is composed of a catheter body 3b (see FIG. 2), a bearing 3a (see FIG. 2) connected to the inside of the tip of the catheter body 3b, and a bearing (not shown) connected to the inside of the base end of the catheter body 3b. The catheter 3 is connected at the tip to the cutter assembly 4, and at the base end to the gripper 6, and has a rotatable twisted wire 1 inside.

As shown in FIG. 2, the tip of the twisted wire 1 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 1 is connected to the rotating shaft of the motor 8.

Therefore, the internal body material D, such as plaque, that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 1 and is transported in the X direction by the rotation of the stranded wire 1.

As shown in Figures 2 to 4, the stranded wire 1 of this embodiment is formed by stranding multiple strands with a roughly circular cross section into a hollow tube so as to form a gap 9 in the center. It is composed of ten first strands 7 (7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7j, 7k) and one second strand 5 that is taller in the radial direction than the first strands 7, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

In addition, in Figures 2 and 3, the second wire 5 is shown with hatching to clearly show that it has a greater radial height than the first wire 7.

As described above, the second wire 5 has a higher radial height than the first wire 7, and also has a cross-sectional shape different from that of the first wire 7. Specifically, the cross-sectional shape of the second wire 5 has two recesses 5b and 5a on the side surface and a nose portion 5x in the region connecting the recesses 5b and 5a, so as to conform to the cross-sectional shapes of the two first wires 7a and 7k adjacent to both sides of the second wire 5.

By making the shape of the second wire 5 irregular in this way, even when the twisted wire 1 is rotated, the second wire 5 does not shift from the first wires 7a and 7k. And the intracorporeal retrieval mechanism 100 can stably retrieve and transport an appropriate amount of material from the patient's body by rotating the twisted wire 1.

The material of the first wire 7 and the second wire 5 is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 7 is described as 10, but 10 is merely an example and is not limited to 10. Any number of wires can be used as long as it can maintain the second wires 5.

In addition, in this embodiment, the two recesses 5b and 5a are formed to conform to the cross-sectional shapes of the two first wires 7a and 7k adjacent to both sides of the second wire 5, but the two recesses 5b and 5a do not necessarily need to be formed to conform to the cross-sectional shapes of the first wires 7a and 7k, and it is sufficient that the recesses 5b and 5a are formed so that at least a portion of the surface of the two adjacent first wires 7a and 7k is accommodated.

However, if the shape of the two recesses 5b and 5a is formed to conform to the cross-sectional shape of the two first wires 7a and 7k adjacent to both sides of the second wire 5, it is possible to prevent the second wire 5 from shifting from the first wires 7a and 7k when the twisted wire 1 is rotated.

Furthermore, in this embodiment, the two recesses 5b and 5a are described as having the same shape, but the two recesses 5b and 5a do not necessarily have to have the same shape, and the shape of recess 5b and the shape of recess 5a may be different as long as a portion of the surface of the first wires 7a and 7k is accommodated therein.

However, if the shape of the two recesses 5a is the same as the shape of the recess 5a, it is possible to prevent the second strand 5 from shifting from the first strands 7a and 7k when the twisted wire 1 is rotated.

The stranded wire 1 of this embodiment is formed by twisting multiple strands with circular cross sections into a tubular shape, and the strands include first strands 7 (7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7j, 7k) and one second strand 5 that is taller in the radial direction than the first strands 7. The second strand 5 has two recesses 5b and 5a where the adjacent first strands 7a and 7k abut in cross section. Therefore, even when the stranded wire 1 is rotated, the second strand 5 does not shift from the first strand 7, and by rotating the stranded wire 1, an appropriate amount of material can be stably collected and transported from the patient's body.

Second Embodiment
Next, a second embodiment of the present invention will be described.
FIG. 5 is a cross-sectional view of a second embodiment of a stranded wire for use in the intracorporeal retrieval system of the present invention.

The second embodiment of the present invention will be described below. The twisted wire 10 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for the common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 10 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 10 is connected to the rotating shaft of the motor 8.

Therefore, the plaque or other body material D that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 10 and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 10.

As shown in FIG. 5, the stranded wire 10 of this embodiment is formed by stranding multiple strands with a roughly circular cross section into a hollow tube so as to form a gap 19 in the center. It is composed of 14 first strands 17 (17a, 17b, 17c, 17d, 17e, 17f, 17g, 17h, 17j, 17k, 17m, 17n, 17p, 17q) and one second strand 15 that is taller in the radial direction than the first strands 17, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

As described above, the second wire 15 has a higher radial height than the first wire 17, and also has a cross-sectional shape different from that of the first wire 17. Specifically, the cross-sectional shape of the second wire 15 has two recesses 15b and 15a on the side and a nose portion 15x in the area connecting the recesses 15b and 15a, so as to conform to the cross-sectional shapes of the two first wires 17a and 17q adjacent to both sides of the second wire 15.

The differences between the second wire 15 and the second wire 5 of the first embodiment are as follows. That is, in the second wire 15, the recesses 15b and 15a are formed on the side of the wire with a substantially circular cross section, whereas in the second wire 5 of the first embodiment, the length of the nose portion 5x is formed slightly longer than the diameter of the substantially circular shape, and is configured not to be further shifted from the first wire 7a and the first wire 7k adjacent to both sides.

Thus, the second wire 15 is slightly inferior to the second wire 5 of the first embodiment in terms of its ability to stay in place relative to the first wire, but the recesses 15b and 15a formed in the second wire 15 can be easily formed on the side of the wire with a substantially circular cross section, making it easier to form the recesses than the second wire 5 of the first embodiment.

The material of the first wire 17 and the second wire 15 is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 17 is described as 14, but 14 is merely an example and is not limited to 14. Any number of wires can be used as long as it can maintain the second wires 15.

In addition, in this embodiment, the two recesses 15b and 15a are formed to conform to the cross-sectional shapes of the two adjacent first wires 17a and 17q on both sides of the second wire 15, but the two recesses 15b and 15a do not necessarily need to be formed to conform to the cross-sectional shapes of the first wires 17a and 17q, and it is sufficient that the recesses 15b and 15a are formed so that at least a portion of the surface of the two adjacent first wires 17a and 17q fits within them.

However, if the shapes of the two recesses 15b and 15a are formed to conform to the cross-sectional shapes of the two first wires 17a and 17q adjacent to both sides of the second wire 15, it is possible to prevent the second wire 15 from shifting from the first wires 17a and 17q when the twisted wire 10 is rotated.

Furthermore, in this embodiment, the two recesses 15b and 15a are described as having the same shape, but the two recesses 15b and 15a do not necessarily have to have the same shape, and the shape of recess 15b and the shape of recess 15a may be different as long as a portion of the surface of the first wires 17a and 17q is accommodated therein.

However, it is better for the shape of the two recesses 15a to be the same as the shape of the recess 15a, so that there is no bias and the second strand 15 is less likely to shift from the first strands 17a and 17q when the twisted wire 10 is rotated.

The stranded wire 10 of this embodiment is formed by twisting multiple strands of circular cross section into a tubular shape, and the strands include first strands 17 (17a, 17b, 17c, 17d, 17e, 17f, 17g, 17h, 17j, 17k, 17m, 17n, 17p, 17q) and one second strand 15 that is higher in the radial direction than the first strands 7. The second strand 15 has two recesses 15b and 15a where the adjacent first strands 17a and 17q abut in cross section. Therefore, even when the stranded wire 10 is rotated, the second strand 15 does not shift from the first strand 17, and by rotating the stranded wire 10, an appropriate amount of material can be stably collected and transported from the patient's body.

Third Embodiment
Next, a third embodiment of the present invention will be described.
FIG. 6 is a cross-sectional view of a third embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention.

The third embodiment of the present invention will be described below. The twisted wire 20 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for the common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 20 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 20 is connected to the rotating shaft of the motor 8.

Therefore, the plaque or other body material D that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 20 and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 20.

As shown in FIG. 6, the stranded wire 20 of this embodiment is formed by stranding multiple strands with a roughly circular cross section into a hollow tube so as to form a void 29 in the center, and is composed of 14 first strands 27 (27a, 27b, 27c, 27d, 27e, 27f, 27g, 27h, 27j, 27k, 27m, 27n, 27p, 27q) and one second strand 25 that is taller in the radial direction than the first strands 27. It is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

As described above, the second wire 25 has a greater radial height than the first wire 27, and also has a different cross-sectional shape than the first wire 27.

Specifically, the cross-sectional shape of the second wire 25 has two recesses 25b and 25a on the side so as to follow the cross-sectional shapes of the two first wires 27a and 27q adjacent to both sides of the second wire 25, and enlarged diameter portions 25q and 25p formed continuously with the recesses 25b and 25a and enlarged in diameter along the first wires 27a and 27q toward the center of the gap 29, and a nose portion 25x in the region connecting the enlarged diameter portions 25q and 25p.

The material of the first wire 27 and the second wire 25 is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 27 is described as 14, but 14 is merely an example and is not limited to 14. Any number of wires can be used as long as it can maintain the second wires 25.

In addition, in this embodiment, the two recesses 25b and 25a are formed to conform to the cross-sectional shapes of the two first strands 27a and 27q adjacent to both sides of the second strand 25, but the two recesses 25b and 25a do not necessarily need to be formed to conform to the cross-sectional shapes of the first strands 27a and 27q, and it is sufficient that the recesses 25b and 25a are formed so that at least a portion of the surface of the two adjacent first strands 27a and 27q is accommodated.

However, if the shapes of the two recesses 25b and 25a are formed to conform to the cross-sectional shapes of the two first wires 27a and 27q adjacent to both sides of the second wire 25, the second wire 25 can be prevented from shifting from the first wires 27a and 27q when the twisted wire 20 is rotated.

Furthermore, in this embodiment, the two recesses 25b and 25a are described as having the same shape, but the two recesses 25b and 25a do not necessarily have to have the same shape, and the shape of recess 25b and the shape of recess 25a may be different as long as a portion of the surface of the first wires 27a and 27q is accommodated therein.

However, if the shape of the two recesses 25a is the same as the shape of the recess 25a, it is possible to prevent the second strand 25 from shifting from the first strands 27a and 27q when the twisted wire 20 is rotated.

According to the twisted wire 20 of this embodiment, a twisted wire is formed by twisting a plurality of strands having a circular cross section into a tubular shape, and the strands include first strands 27 (27a, 27b, 27c, 27d, 27e, 27f, 27g, 27h, 27j, 27k, 27m, 27n, 27p, 27q) and one second strand 25 having a higher radial height than the first strands 27, and the second strand 25 is twisted relative to the adjacent first strands 27a and The two recesses 25b and 25a where the first wires 27a and 27q come into contact, and the recesses 25b and 25a have enlarged diameters 25q and 25p where the first wires 27a and 27k come into contact when viewed in cross section, so that when the stranded wire 20 is rotated, the second wires 25 do not shift further, and by rotating the stranded wire 20, an appropriate amount of material can be more stably collected and transported from the patient's body.

Fourth Embodiment
Next, a fourth embodiment of the present invention will be described.
FIG. 7 is a cross-sectional view of a fourth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention.

The fourth embodiment of the present invention will be described below. The twisted wire 30 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for the common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 30 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 30 is connected to the rotating shaft of the motor 8.

Therefore, the plaque or other body material D that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 30, and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 30.

As shown in FIG. 7, the stranded wire 30 of this embodiment is formed by stranding multiple strands with a substantially circular cross section into a hollow tube so as to form a void 39 in the center. It is composed of 13 first strands 37 (37a, 37b, 37c, 37d, 37e, 37f, 37g, 37h, 37j, 37k, 37m, 37n, 37p), one second strand 35a that is taller in the radial direction than the first strands 37, and one second strand 35b that is taller in the radial direction than the first strands 37 and is located at a position rotated 180° in cross section from the second strand 35a, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

As described above, the second wires 35a and 35b have a greater radial height than the first wire 37, and also have a different cross-sectional shape than the first wire 37.

Specifically, the cross-sectional shape of the second wire 35a is shaped to follow the cross-sectional shapes of the two first wires 37a and 37p adjacent to both sides of the second wire 35a, with two recesses 35ab and 35aa on the side, enlarged diameter portions 35aq and 35ap formed continuously with the recesses 35ab and 35aa and enlarged in diameter along the first wires 37a and 37p toward the center of the gap 39, and a nose portion 35ax in the region connecting the enlarged diameter portions 35aq and 35ap.

The cross-sectional shape of the second wire 35b is shaped to follow the cross-sectional shapes of the two first wires 37g and 37f adjacent to both sides of the second wire 35b, with two recesses 35bb and 35ba on the side, enlarged diameter portions 35bq and 35bp formed continuously with the recesses 35bb and 35ba and enlarged in diameter along the first wires 37g and 37f toward the center of the gap 39, and a nose portion 35bx in the region connecting the enlarged diameter portions 35bq and 35bp.

The material of the first wire 37 and the second wires 35a and 35b is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 37 is described as 13, but 13 is merely an example and is not limited to 13. Any number of wires can be used as long as they can maintain the second wires 35a and 35b.

In addition, in this embodiment, the number of second wires 35 is described as two, but two is merely an example and is not limited to two. Any number of wires may be used as long as a gap G is secured that can collect and transport internal substances D such as plaque.

In addition, in this embodiment, the positional relationship between the two second wires, second wire 35a and second wire 35b, has been described as a positional relationship with a rotation angle of 180°, but if there are three second wires, the positional relationship may be 120°, and if there are four second wires, the positional relationship may be 90°, etc., and each second wire may be arranged in an uneven positional relationship. Any positional relationship may be used as long as it ensures a gap G that can collect and transport internal substances D such as plaque.

Furthermore, in this embodiment, the second wire is described as having a configuration similar to that of the second wire 25 of the third embodiment, but the second wire 5 of the first embodiment or the second wire 15 of the second embodiment may also be used as the second wire of this embodiment.

In addition, in this embodiment, the two recesses 35ab and 35aa are formed to conform to the cross-sectional shapes of the two first wires 37a and 37p adjacent to both sides of the second wire 35a, but the two recesses 35ab and 35aa do not necessarily need to be formed to conform to the cross-sectional shapes of the first wires 37a and 37p, and it is sufficient that the recesses 35ab and 35aa are formed so that at least a portion of the surface of the two adjacent first wires 37a and 37p is accommodated.

However, if the shapes of the two recesses 35ab and 35aa are formed to conform to the cross-sectional shapes of the two first wires 37a and 37p adjacent to both sides of the second wire 35a, it is possible to prevent the second wire 35a from shifting from the first wires 37a and 37p when the twisted wire 30 is rotated.

Furthermore, in this embodiment, the two recesses 35ab and 35aa are described as having the same shape, but the two recesses 35ab and 35aa do not necessarily have to have the same shape, and the shape of recess 35ab and the shape of recess 35aa may be different as long as they can accommodate a portion of the surface of the first wires 37a and 37p.

However, it is better for the two recesses 35ab and 35aa to have the same shape so that there is no bias and the second strand 35a is less likely to shift from the first strands 37a and 37p when the stranded wire 30 is rotated.

Note that the above points regarding the second wire 35a also apply to the second wire 35b.

According to the stranded wire 30 of this embodiment, a stranded wire is formed by stranding a plurality of strands having a circular cross section into a tubular shape, and the strands include a first strand 37 (37a, 37b, 37c, 37d, 37e, 37f, 37g, 37h, 37j, 37k, 37m, 37n, 37p) and two second strands 35a and 35b that are higher in the radial direction than the first strands 37. The second strand 35a has two recesses 35ab and 35aa where the adjacent first strands 37a and 37p abut in a cross-sectional view, and the recesses 35ab and 35aa are aligned along the first strands 37a and 37p on the tubular center side in a cross-sectional view. The other second strand 35b has two recesses 35bb and 35ba where the adjacent first strands 37g and 37f abut in cross section, and the recesses 35bb and 35ba have expanded diameters 35bq and 35bp along the first strands 37g and 37f on the tubular center side in cross section. Therefore, even when the strand 30 is rotated, the second strands 35a and 35b do not shift, and by rotating the strand 30, an appropriate amount of material can be collected and transported more stably from the patient's body.

Fifth Embodiment
Next, a fifth embodiment of the present invention will be described.
FIG. 8 is a cross-sectional view of a fifth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention.

The fifth embodiment of the present invention will be described below. The twisted wire 40 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 40 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 40 is connected to the rotating shaft of the motor 8.

Therefore, the plaque or other body material D that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 40, and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 40.

As shown in FIG. 8, the stranded wire 40 of this embodiment is formed by stranding multiple strands with a roughly circular cross section into a hollow tube so as to form a gap 49 in the center, and is composed of 12 first strands 47 (47a, 47b, 47c, 47d, 47e, 47f, 47g, 47h, 47j, 47k, 47m, 47n) and two adjacent second strands 45a and 45b that are radially taller than the first strands 47, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

As described above, the second wires 45a and 45b have a greater radial height than the first wire 47, and also have a different cross-sectional shape than the first wire 47.

Specifically, the cross-sectional shape of the second wire 45a has one recess 45aa on the side so as to conform to the cross-sectional shape of one first wire 47n adjacent to one side of the second wire 45a, and the cross-sectional shape of the second wire 45b has one recess 45ba on the side so as to conform to the cross-sectional shape of one first wire 47a adjacent to one side of the second wire 45b.

The material of the first wire 47 and the second wires 45a and 45b is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 47 is described as 12, but 12 is merely an example and is not limited to 12, and any number can be used as long as it can maintain the second wires 45a and 45b.

In addition, in this embodiment, the number of second wires 45 has been described as two, but two is merely an example and is not limited to two. Any number of adjacent wires may be used as long as a gap G is secured that can collect and transport internal body substances D such as plaque.

In addition, in this embodiment, the two recesses 45ba and 45aa are formed to conform to the cross-sectional shape of one of the first wires 47n and 47a adjacent to one side of the second wire 45a and the second wire 45b, but the two recesses 45ba and 45aa do not necessarily have to be formed to conform to the cross-sectional shape of the first wires 47n and 47a, and it is sufficient that the recesses 45ba and 45aa are formed so that at least a portion of the surface of the two adjacent first wires 47n and 47a is accommodated.

However, if the shape of the two recesses 45ba and 45aa is formed to conform to the cross-sectional shape of one of the first wires 47n and 47a adjacent to one side of the second wires 45a and 45b, the second wires 45a and 45b can be prevented from shifting from the first wires 47n and 47a when the twisted wire 40 is rotated.

Furthermore, in this embodiment, the two recesses 45ba and 45aa are described as having the same shape, but the two recesses 45ba and 45aa do not necessarily have to have the same shape, and the shape of the recess 45ba and the shape of the recess 45aa may be different as long as a portion of the surface of the first wires 47n and 47a is accommodated therein.

However, it is better for the two recesses 45ba and 45aa to have the same shape so that there is no bias and the second strands 45a and 45b are less likely to shift from the first strands 47n and 47a when the twisted wire 40 is rotated.

The stranded wire 40 of this embodiment is formed by twisting multiple strands of circular cross section into a tubular shape, and the strands include first strands 47 (47a, 47b, 47c, 47d, 47e, 47f, 47g, 47h, 47j, 47k, 47m, 47n) and two second strands 45a and 45b that are higher in the radial direction than the first strands 47. The second strands 45a and 45b have one recess 45aa where the adjacent first strands 47n abut in a cross-sectional view, and one recess 45ba where the first strand 47a abuts. Therefore, when the stranded wire 40 is rotated, the second strands 45a and 45b do not shift, and by rotating the stranded wire 40, an appropriate amount of material can be more stably collected and transported from the patient's body.

Sixth Embodiment
Next, a sixth embodiment of the present invention will be described.
FIG. 9 is a cross-sectional view of a sixth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention.

The sixth embodiment of the present invention will be described below. The twisted wire 50 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 50 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 50 is connected to the rotating shaft of the motor 8.

Therefore, the plaque or other body material D that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 50, and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 50.

As shown in FIG. 9, the stranded wire 50 of this embodiment is formed by stranding multiple strands that are annular sector-shaped in cross section into a hollow tube so as to form a gap 59 in the center. It is composed of 15 first strands 57 (57a, 57b, 57c, 57d, 57e, 57f, 57g, 57h, 57j, 57k, 57m, 57n, 57p, 57q, 57r) and one second strand 55 that is taller in the radial direction than the first strands 57, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

As described above, the second wire 55 has a higher radial height than the first wire 57, and has a different cross-sectional shape from the first wire 57. Specifically, the cross-sectional shape of the second wire 55 is composed of two line segments 55a and 55b that are approximately parallel to the center line CL5 from the tubular center C5, a nose portion 55x formed in the area connecting the line segments 55a and 55b, and a circular portion 55c that is continuous with the line segments 55a and 55b.

The material of the first wire 57 and the second wire 55 is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 57 is described as 15, but 15 is merely an example and is not limited to 15. Any number of wires can be used as long as it can maintain the second wires 55.

In addition, in this embodiment, the cross-sectional shape of the first wire 57 is an annular sector shape, but it is not limited to an annular sector shape, and may be a generally rectangular shape in cross section, a so-called flat wire, which will be described later, or a circular or elliptical shape in cross section.

The stranded wire 50 of this embodiment is formed by twisting multiple strands into a tubular shape, and the strands include first strands 57 (57a, 57b, 57c, 57d, 57e, 57f, 57g, 57h, 57j, 57k, 57m, 57n, 57p, 57q, 57r) and one second strand 55 that is higher in the radial direction than the first strands 57. The second strand 55 has two line segments 55a and 55b that are approximately parallel to the tubular center line CL5 in a cross-sectional view, and is in contact with the adjacent first strands 57a and 57r on the two line segments 55a and 55b. Therefore, when the stranded wire 50 is rotated, the second strand 55 does not shift, and by rotating the stranded wire 50, an appropriate amount of material can be more stably collected and transported from the patient's body.

Seventh Embodiment
Next, a seventh embodiment of the present invention will be described.
FIG. 10 is a cross-sectional view of a seventh embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention.

The seventh embodiment of the present invention will be described below. The twisted wire 60 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 60 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 60 is connected to the rotating shaft of the motor 8.

Therefore, the internal body material D, such as plaque, that is cut by the cutter 4c and taken inside the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 60 and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 60.

As shown in FIG. 10, the stranded wire 60 of this embodiment is formed by stranding multiple strands of approximately rectangular cross section into a hollow tube so as to form a gap 69 in the center, and is composed of 15 first strands 67 (67a, 67b, 67c, 67d, 67e, 67f, 67g, 67h, 67j, 67k, 67m, 67n, 67p, 67q, 67r) and one second strand 65 of approximately rectangular cross section that is taller in the radial direction than the first strands 67, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

The cross-sectional shape of the second wire 65 is specifically composed of two line segments 65a and 65b that are approximately parallel to the center line CL6 from the tubular center C6, and an inner line segment 65c and an outer line segment 65d that connect line segments 65a and 65b.

The material of the first wire 67 and the second wire 65 is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 67 is described as 15, but 15 is merely an example and is not limited to 15. Any number of wires can be used as long as it can maintain the second wires 65.

In addition, in this embodiment, the first wire 67 has a generally rectangular cross section, but this is not limited to a generally rectangular shape, and may be an annular sector shape as described above, or a circular or elliptical cross section.

According to the twisted wire 60 of this embodiment, a twisted wire is formed by twisting a plurality of strands into a tubular shape, and the strands include first strands 67 (67a, 67b, 67c, 67d, 67e, 67f, 67g, 67h, 67j, 67k, 67m, 67n, 67p, 67q, 67r) and a single second strand 65 that is generally rectangular in cross section and has a radial height greater than the first strands 67. The second strand 65 has two line segments 65a and 65b that are generally parallel to the tubular center line CL6 in cross section, and abuts the adjacent first strands 67a and 67r on the two line segments 65a and 65b. Therefore, when the twisted wire 60 is rotated, the second strand 65 does not shift, and by rotating the twisted wire 60, an appropriate amount of substance can be more stably collected and transported from the patient's body.

In addition, according to the stranded wire 60 of this embodiment, the second wire 65 has a generally rectangular cross section, so it is easy to manufacture a stranded wire in which the second wire 65 does not shift.

Eighth embodiment
Next, an eighth embodiment of the present invention will be described.
FIG. 11 is a cross-sectional view of an eighth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention.

The eighth embodiment of the present invention will be described below. The twisted wire 70 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 70 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 70 is connected to the rotating shaft of the motor 8.

Therefore, the plaque or other bodily material D that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 70, and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 70.

As shown in FIG. 11, the stranded wire 70 of this embodiment is formed by stranding multiple strands of approximately rectangular cross section into a hollow tube so as to form a gap 79 in the center, and is composed of 15 first strands 77 (77a, 77b, 77c, 77d, 77e, 77f, 77g, 77h, 77j, 77k, 77m, 77n, 77p, 77q, 77r) and one second strand 75 of approximately square cross section that is taller in the radial direction than the first strands 77, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

The cross-sectional shape of the second wire 75 is specifically composed of two line segments 75a and 75b that are approximately parallel to the center line CL7 from the tubular center C7, and an inner line segment 75c and an outer line segment 75d that connect line segments 75a and 75b.

The material of the first wire 77 and the second wire 75 is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 77 is described as 15, but 15 is merely an example and is not limited to 15. Any number of wires can be used as long as it can maintain the second wires 75.

In addition, in this embodiment, the first wire 77 has a generally rectangular cross section, but this is not limited to a generally rectangular cross section, and may be an annular sector shape as described above, or a circular or elliptical cross section.

According to the twisted wire 70 of this embodiment, a twisted wire is formed by twisting a plurality of strands into a tubular shape, and the strands include first strands 77 (77a, 77b, 77c, 77d, 77e, 77f, 77g, 77h, 77j, 77k, 77m, 77n, 77p, 77q, 77r) and a single second strand 75 that is approximately square in cross section and has a radial height greater than the first strands 77. The second strand 75 has two line segments 75a and 75b that are approximately parallel to the tubular center line CL7 in cross section, and abuts the adjacent first strands 77a and 77r on the two line segments 75a and 75b. Therefore, when the twisted wire 70 is rotated, the second strand 75 does not shift, and by rotating the twisted wire 70, an appropriate amount of substance can be more stably collected and transported from the patient's body.

In addition, according to the stranded wire 70 of this embodiment, the second strands 75 are roughly square in cross section, so it is easy to manufacture a stranded wire in which the second strands 75 do not shift.

Ninth embodiment
Next, a ninth embodiment of the present invention will be described.
FIG. 12 is a cross-sectional view of a ninth embodiment of a stranded wire for use in the intracorporeal retrieval mechanism of the present invention.

The ninth embodiment of the present invention will be described below. The twisted wire 80 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 80 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 80 is connected to the rotating shaft of the motor 8.

Therefore, the plaque or other body material D that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 80, and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 80.

As shown in FIG. 12, the stranded wire 80 of this embodiment is formed by stranding a plurality of strands having an annular sector shape in cross section into a hollow tube shape so as to form a void 89 in the center. The stranded wire 80 is composed of 14 first strands 87 (87a, 87b, 87c, 87d, 87e, 87f, 87g, 87h, 87j, 87k, 87m, 87n, 87p, 87q), one second strand 85a having a generally square shape in cross section and a higher radial height than the first strands 87, and one second strand 85b located 180° rotated in cross section from the second strand 85a and having a higher radial height than the first strand 87. The stranded wire 80 is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

The cross-sectional shape of the second wire 85a is specifically composed of two line segments 85ab and 85aa that are approximately parallel to the center line CL8 from the tubular center C8, and an inner line segment 85ac and an outer line segment 85ad that connect the line segments 85ab and 85aa.

More specifically, the cross-sectional shape of the second wire 85b is composed of two line segments 85bb and 85ba that are approximately parallel to the center line CL8 from the tubular center C8, and an inner line segment 85bc and an outer line segment 85bd that connect the line segments 85bb and 85ba.

The material of the first wire 87 and the second wires 85a and 85b is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 87 is described as 14, but 14 is merely an example and is not limited to 14. Any number of wires can be used as long as they can maintain the second wires 85a and 85b.

In addition, in this embodiment, the number of second wires 85 is described as two, but two is merely an example and is not limited to two. Any number of wires may be used as long as a gap G is secured that can collect and transport internal substances D such as plaque.

In addition, in this embodiment, the positional relationship between the two second wires, second wire 85a and second wire 85b, has been described as a positional relationship with a rotation angle of 180°, but if there are three second wires, the positional relationship may be an equal positional relationship, such as a positional relationship with a rotation angle of 120°, and if there are four second wires, the positional relationship may be a rotation angle of 90°, or each second wire may be arranged in an unequal positional relationship. Any positional relationship may be used as long as it ensures a gap G that can collect and transport internal substances D such as plaque.

In addition, in this embodiment, the cross-sectional shape of the first wire 87 is an annular sector shape, but this is not limited to an annular sector shape, and may be a roughly rectangular, circular, or elliptical cross-sectional shape.

According to the stranded wire 80 of this embodiment, a stranded wire is formed by stranding a plurality of strands into a tubular shape, and the strands include first strands 87 (87a, 87b, 87c, 87d, 87e, 87f, 87g, 87h, 87j, 87k, 87m, 87n, 87p, 87q) and two second strands 85a and 85b that are approximately square in cross section and have a higher radial height than the first strands 87. The second strand 85a has a It has two line segments 85ab and 85aa that are approximately parallel to the tubular center line CL8 when viewed from above, and the two line segments 85ab and 85aa abut the adjacent first strands 87a and 87q, so when the stranded wire 80 is rotated, the second strand 85a does not shift, and by rotating the stranded wire 80, an appropriate amount of material can be collected and transported from the patient's body more stably.

In addition, the second wire 85b has two line segments 85ba and 85bb that are approximately parallel to the tubular center line CL8 in a cross-sectional view, and abuts the adjacent first wires 87h and 87g on the two line segments 85ba and 85bb. Therefore, when the stranded wire 80 is rotated, the second wire 85b does not shift, and by rotating the stranded wire 80, an appropriate amount of substance can be more stably collected and transported from the patient's body.

In addition, according to the stranded wire 80 of this embodiment, the second strands 85a and 85b are approximately square in cross section, so it is easy to manufacture a stranded wire in which the second strands 85a and 85b do not shift.

Tenth embodiment
Next, a tenth embodiment of the present invention will be described.
FIG. 13 is a cross-sectional view of a stranded wire according to a tenth embodiment for use in the intracorporeal retrieval mechanism of the present invention.

The tenth embodiment of the present invention will be described below. The twisted wire 90 of this embodiment is used in the internal recovery mechanism 100 in which the twisted wire 1 of the first embodiment is used. The same reference numerals are used for common parts, and the description will be omitted.

As in FIG. 2, the tip of the twisted wire 90 in this embodiment is connected to the base end of the cutter 4c through a bearing 3a connected to the inside of the tip of the catheter 3, and the base end of the twisted wire 90 is connected to the rotating shaft of the motor 8.

Therefore, the plaque or other bodily material D that is cut by the cutter 4c and taken into the cutter assembly 4 is held in the gap G formed between the catheter 3 and the stranded wire 90, and is transported in the X direction (see Figure 2) by the rotation of the stranded wire 90.

As shown in FIG. 13, the stranded wire 90 of this embodiment is formed by stranding multiple strands that are annular in cross section into a hollow tube so as to form a gap 99 in the center. It is composed of 13 first strands 97 (97a, 97b, 97c, 97d, 97e, 97f, 97g, 97h, 97j, 97k, 97m, 97n, 97p) and two adjacent second strands 95a and 95b that are radially taller than the first strands 97, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

The cross-sectional shape of the second wire 95a is specifically composed of one line segment 95aa that is approximately parallel to the center line CL9a from the tubular center C9, a circular portion 95ac that is continuous with the line segment 95aa, and a nose portion 95ax that is formed in the area that connects the line segment 95aa and the circular portion 95ac.

More specifically, the cross-sectional shape of the second wire 95b is composed of one line segment 95ba that is approximately parallel to the center line CL9b from the tubular center C9, a circular portion 95bc that is continuous with the line segment 95ba, and a nose portion 95bx that is formed in the area that connects the line segment 95ba and the circular portion 95bc.

The material of the first wire 97 and the second wires 95a and 95b is not particularly limited as long as it is a biocompatible material, such as stainless steel, Ni-Ti alloy, or cobalt alloy, but stainless steel is used in this embodiment.

In addition, in this embodiment, the number of first wires 97 is described as 13, but 13 is merely an example and is not limited to 13. Any number of wires can be used as long as they can maintain the second wires 95a and 95b.

In addition, in this embodiment, the number of second wires 95 is described as two, but two is merely an example and is not limited to two. Any number of wires may be used as long as a gap G is secured that can collect and transport internal substances D such as plaque.

In addition, in this embodiment, the cross-sectional shape of the first wire 97 is an annular sector shape, but this is not limited to an annular sector shape, and may be a roughly rectangular, circular, or elliptical cross-sectional shape.

The stranded wire 90 of this embodiment is formed by twisting multiple strands into a tubular shape, and the strands include a first strand 97 (97a, 97b, 97c, 97d, 97e, 97f, 97g, 97h, 97j, 97k, 97m, 97n, 97p) and two adjacent second strands 95a and 95b that are higher in the radial direction than the first strands 97. The second strand 95a has one line segment 95aa that is approximately parallel to the tubular center line CL9a in a cross-sectional view, and abuts the adjacent first strand 97p on the one line segment 95aa. Therefore, when the stranded wire 90 is rotated, the second strand 95a does not shift, and by rotating the stranded wire 90, an appropriate amount of material can be more stably collected and transported from the patient's body.

In addition, the second wire 95b has one line segment 95ba that is approximately parallel to the tubular center line CL9b in a cross-sectional view, and abuts the adjacent first wire 97a on that one line segment 95ba. Therefore, when the twisted wire 90 is rotated, the second wire 95b does not shift, and by rotating the twisted wire 90, an appropriate amount of substance can be more stably collected and transported from the patient's body.

1, 10, 20, 30, 40, 50, 60, 70, 80, 90... stranded wire 3... catheter (housing)
4... Cutter assembly 4c... Cutter 5, 15, 25, 35a, 35b, 45a, 45b, 55, 65, 75, 85a, 85b, 95a, 95b... Second wire 5a, 5b, 15a, 15b, 25a, 25b, 35aa, 35ab, 35ba, 35bb, 45aa, 45ba... Recess 6... Grip portion 7, 17, 27, 37, 47, 57, 67, 77, 87 , 97... First wire 8... Motor 25p, 25q, 35ap, 35aq, 35bp, 35bq... Expanded portion 55a, 55b, 65a, 65b, 75a, 75b, 85aa, 85ab, 85ba, 85bb, 95aa, 95ba... Line segment 100... Internal retrieval mechanism CL5, CL6, CL7, CL8, CL9a, CL9b... Center line D... Internal substance G... Gap

Claims (7)

A stranded wire characterized in that it is formed by stranding a plurality of first wires having a generally circular cross section and at least one second wire having an outer diameter larger than the first wires and also having a generally circular cross section, the second wire being configured to have at least one recess on the contact surface with an adjacent first wire , into a hollow tubular shape . The stranded wire according to claim 1, characterized in that at least one of the second strands has two recesses on the contact surface with the adjacent first strand. 3. The stranded wire according to claim 1, wherein the at least one second strand has a recess that expands in diameter along the first strand on a center side of the hollow tube in a cross-sectional view. A stranded wire characterized in that it is formed by twisting a plurality of first strands into the hollow tubular shape, and at least one second strand, which protrudes radially outward from the first strands and has at least one line segment that is approximately parallel to a center line of the hollow tubular shape in a cross-sectional view, and is configured to abut against an adjacent first strand on the at least one line segment. 5. The stranded wire according to claim 4, characterized in that at least one of the second wires has two line segments that are approximately parallel to a center line of the hollow tube in a cross-sectional view, and abuts adjacent first wires on the two line segments. The stranded wire according to claim 4 or 5, characterized in that at least one of the second strands has a cross section that is approximately square or approximately rectangular. A long housing;
a cutter rotatably connected to a tip of the housing;
The stranded wire according to any one of claims 1 to 6, which is rotatably disposed within the housing and has a tip connected to the cutter;
An internal retrieval mechanism comprising:

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