Stranded wire and internal retrieval mechanism including the stranded wire

Abstract

To provide a twisted wire and an internal recovery mechanism comprising the twisted wire, the twisted wire having a thick wire inhibited from deviating from a thin wire when being rotated to make it possible to stably recover and convey an appropriate amount of material from the inside of a patient's body.SOLUTION: A twisted wire 1 is formed by twisting a plurality of element wires having a circular cross section into a tubular shape. The element wires include first element wires 17 (17a, 17b, 17c, 17d, 17e, 17f, 17g, 17h, 17j, 17k, 17m, 17n, 17p, 17q) and a single second element wire 15 having a height in a radial direction greater than those of the first element wires 7. The second element wire 15 has two recesses 15b and 15a on which the first element wires 17a and 17k adjacent in a cross sectional view abut, respectively.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a stranded wire formed by stranding a plurality of strands, and to an in vivo retrieval mechanism that includes the stranded wire and is used to remove substances from within the body. [Background technology]

[0002] Conventionally, various devices have been developed to remove substances from inside the body of a patient. For example, Patent Document 1 describes a medical treatment tool that includes a distal tip 70 and a coil spring body 54 that is connected to the base end side of the distal 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 the body of a patient by rotating the distal tip 70 and the coil spring body 54 (see FIG. 16, etc.). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-98120 A Summary of the Invention [Problem to be solved by the invention]

[0004] 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, and as a result, the amount by which the thick wire 54a protrudes from the outer periphery of the thin wire 54b is small, resulting in a problem that the amount of material removed per rotation of the coil spring 54 is small.

[0005] 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 that case, there is a problem in that the thick wire 54a becomes more likely to shift outward from the thin wire 54b.

[0006] The present invention has been made in response to the above-mentioned problems of the prior art, and aims to provide a coil spring (hereinafter referred to as "stranded wire") that can stably retrieve and transport an appropriate amount of substance from within a patient's body without the thick wire shifting from the thin wire when rotated, and an in-body retrieval mechanism equipped with this stranded wire. [Means for solving the problem]

[0007] In order to solve the above problems, the first aspect of the present invention Stranded wire is a plurality of substantially circular cross sections No. 1 wire, At least one wire having a substantially circular cross section and a larger outer diameter than the first wire, the wire being configured to have at least one recess on an abutment surface with the adjacent first wire. A second wire, and It is twisted into a hollow tube shape. It is characterized by:

[0008] In addition, a second aspect of the present invention is characterized in that, in the stranded wire of the first aspect, at least one of the second wires has two recesses where adjacent first wires abut in a cross-sectional view.

[0009] In addition, a third aspect of the present invention is a stranded wire according to the first or second aspect, wherein the at least one second wire has the recess in a cross-sectional view. hollow The tubular core is characterized in that its diameter is expanded along the first wire at the center thereof.

[0010] Moreover, the fourth aspect of the present invention Stranded wire is multiple No. 1 wire, At least one wire having at least one line segment that protrudes radially outward from the first wire and is substantially parallel to a center line of the hollow tube in a cross-sectional view, and is configured to abut against an adjacent first wire on the at least one line segment. A second wire, and The hollow tubular shape is formed by twisting. It is characterized by:

[0011] In a fifth aspect of the present invention, in the stranded wire according to the fourth aspect, at least one of the second wires has a cross-sectional shape as described above. hollow The wire has two line segments that are substantially parallel to a tubular center line, and is in contact with adjacent first wires on the two line segments.

[0012] A sixth aspect of the present invention is the stranded wire according to the fourth or fifth aspect, wherein the at least one second wire has a substantially square or rectangular cross section.

[0013] Furthermore, the intracorporeal retrieval mechanism of the seventh aspect of the present invention is characterized in that it comprises a long-shaped 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. Effect of the Invention

[0014] First aspect of the present invention Stranded wire According to the method, a plurality of substantially circular cross sections No. 1 wire, At least one wire having a substantially circular cross section and a larger outer diameter than the first wire, the wire being configured to have at least one recess on an abutment surface with the adjacent first wire. A second wire, and It is twisted into a hollow tube shape. Therefore, even when the stranded wire is rotated, the second strand does not shift, and by rotating the stranded wire, an appropriate amount of substance can be stably collected and transported from the patient's body.

[0015] Furthermore, according to the second aspect of the present invention, in the stranded wire of the first aspect, at least one second wire has two recesses where adjacent first wires abut in cross-section. Therefore, when the stranded wire is rotated, the second wires do not become further misaligned, and by rotating the stranded wire, an appropriate amount of substance can be more stably recovered and transported from the patient's body.

[0016] According to a third aspect of the present invention, in the stranded wire according to the first or second aspect, at least one second wire has a recess in cross section. hollowSince the diameter expands along the first wire at the center of the tubular shape, 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 collected and transported from the patient's body.

[0017] Moreover, the fourth aspect of the present invention Stranded wire According to several No. 1 wire, At least one wire having at least one line segment that protrudes radially outward from the first wire and is substantially parallel to a center line of the hollow tube in a cross-sectional view, and is configured to abut against an adjacent first wire on the at least one line segment. A second wire, and The hollow tubular shape is formed by twisting. Therefore, even when the stranded wire is rotated, the second strand does not shift, and by rotating the stranded wire, an appropriate amount of substance can be stably collected and transported from the patient's body.

[0018] According to a fifth aspect of the present invention, in the stranded wire according to the fourth aspect, at least one second wire has a cross section as follows: hollow It has two lines that are approximately parallel to a tubular center line and abut against adjacent first wires on the two lines, 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 collected and transported from the patient's body.

[0019] Furthermore, according to the sixth aspect of the present invention, in the stranded wire of the fourth or fifth aspect, at least one second strand has a substantially square or rectangular cross section. Therefore, in addition to the advantageous effects of the stranded wire of the fourth or fifth aspect, a stranded wire can be easily manufactured in which the second stranded wire does not shift.

[0020] Furthermore, according to the seventh aspect of the present invention, the in vivo retrieval mechanism comprises 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, thereby making it possible to stably retrieve and transport an appropriate amount of substance from the patient's body. [Brief description of the drawings]

[0021] [Figure 1]FIG. 2 is an external view of the in vivo retrieval mechanism of the present invention. [Diagram 2] FIG. 2 is an explanatory diagram of the inside of part A in FIG. [Diagram 3] FIG. 2 is an enlarged view of a first embodiment of a stranded wire used in the intracorporeal retrieval mechanism of the present invention. [Figure 4] BB cross-sectional view of FIG. 3. [Diagram 5] FIG. 2 is a cross-sectional view of a second embodiment of a stranded wire used in the intracorporeal retrieval mechanism of the present invention. [Figure 6] FIG. 11 is a cross-sectional view of a third embodiment of a stranded wire used in the intracorporeal retrieval mechanism of the present invention. [Figure 7] FIG. 11 is a cross-sectional view of a fourth embodiment of a stranded wire used in the intracorporeal retrieval mechanism of the present invention. [Figure 8] FIG. 13 is a cross-sectional view of a stranded wire according to a fifth embodiment for use in the intracorporeal retrieval mechanism of the present invention. [Figure 9] FIG. 13 is a cross-sectional view of a stranded wire according to a sixth embodiment for use in the intracorporeal retrieval mechanism of the present invention. [Figure 10] FIG. 13 is a cross-sectional view of a seventh embodiment of a stranded wire used in the intracorporeal retrieval mechanism of the present invention. [Figure 11] FIG. 13 is a cross-sectional view of an eighth embodiment of a stranded wire used in the intracorporeal retrieval mechanism of the present invention. [Figure 12] FIG. 13 is a cross-sectional view of a stranded wire according to a ninth embodiment for use in the intracorporeal retrieval mechanism of the present invention. [Figure 13] 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. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0023] (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 BB in FIG. 3.

[0024] In addition, for the stranded wire described in this embodiment and in the embodiments described later, the cross section of the actual wires cut perpendicular to the axial direction of the stranded wire will be slightly elliptical in shape depending on the twist angle of the stranded wire in the case of a wire with a circular cross section, will be a slightly deformed annular sector shape depending on the twist angle of the stranded wire in the case of a wire with an annular sector shape in cross section, and will be a slightly deformed rectangular shape depending on the twist angle of the stranded wire in the case of a wire with a generally rectangular cross section; however, for convenience of explanation, the cross-sectional shapes of the wires constituting the stranded wire in Figures 4 to 13 are shown schematically and differ from the cross-sectional shapes of the actual wires.

[0025] That is, the strands constituting the strands shown in Figures 4 to 8 are described as strands with circular cross sections 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 annular sector cross sections 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 approximately rectangular cross sections cut at right angles to the twist angle of the strands.

[0026] 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) consisting 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.

[0027] The cutter assembly 4 includes a cover body 4b that is connected to the tip of the catheter 3 and has multiple openings 4a, and a cutter 4c that is disposed inside the cover body 4b. The cutter 4c is connected to the tip of the stranded wire 1 (see FIG. 2) that will be described later, and is rotatable with the rotation of the motor 8.

[0028] Therefore, the cutter assembly 4 cuts the intracorporeal matter 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 the material into the cutter assembly 4.

[0029] The grip portion 6 is connected to the base end of the catheter 3 and is composed of a grip portion main body 6a and a U-shaped grip portion side body 6b connected to the grip portion main body 6a. In addition, a space S is formed in the grip portion 6 between the grip portion main body 6a and the grip portion side body 6b so that the operator can grasp the grip portion 6.

[0030] Moreover, the main body of the motor 8 is connected to the base end of the gripping portion 6, and the rotating shaft of the motor 8 is connected to the base end of the stranded wire 1 (see FIG. 2) which will be described later.

[0031] In Figures 1 and 2, the cutter assembly 4 is connected in a straight line to the catheter 3, and although the mechanism for this is not shown, in reality, the cutter assembly 4 can be bent in all directions 360 degrees relative to the long axis of the catheter 3 by operating the gripping portion 6.

[0032] 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 end 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 has a tip connected to a cutter assembly 4, a base connected to a gripping portion 6, and includes a rotatable stranded wire 1 inside.

[0033] As shown in FIG. 2, the tip of the stranded 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 stranded wire 1 is connected to the rotating shaft of the motor 8.

[0034] Therefore, bodily matter 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 1 and is transported in the X direction by the rotation of the stranded wire 1.

[0035] As shown in Figures 2 to 4, the stranded wire 1 of this embodiment is formed by stranding a plurality of strands having an approximately circular cross section into a hollow tubular shape so as to form a gap 9 in the center, and is composed of ten first strands 7 (7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7j, 7k) and one second strand 5 that is radially taller than the first strands 7, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

[0036] 2 and 3, the second wires 5 are shown by hatching in order to clearly show that they are taller in the radial direction than the first wires 7.

[0037] 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 its side surface, and a nose portion 5x in a region connecting the recesses 5b and 5a, so as to follow the cross-sectional shapes of the two first wires 7a and 7k adjacent to both sides of the second wire 5.

[0038] By making the shape of the second wire 5 different in this way, the second wire 5 will not become displaced from the first wires 7a and 7k even when the stranded wire 1 is rotated. Thus, the intracorporeal retrieval mechanism 100 can stably retrieve and transport an appropriate amount of material from the patient's body by rotating the stranded wire 1.

[0039] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0040] In addition, in this embodiment, the number of first wires 7 has been described as 10, but 10 is merely an example and is not limited to 10, and the number can be any number that can support the second wires 5.

[0041] 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 have 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 as to accommodate at least a portion of the surfaces of the two adjacent first wires 7a and 7k.

[0042] However, forming the shapes of the two recesses 5b and 5a to conform to the cross-sectional shapes of the two first wires 7a and 7k adjacent to both sides of the second wire 5 makes it possible to prevent the second wire 5 from shifting out of place from the first wires 7a and 7k when the twisted wire 1 is rotated.

[0043] Furthermore, in this embodiment, the two recesses 5b and 5a have been 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 they can accommodate a portion of the surface of the first wires 7a and 7k.

[0044] However, if the shapes of the two recesses 5a and the shape of the recess 5a are the same, it is possible to prevent bias and to prevent the second wire 5 from shifting from the first wires 7a and 7k when the stranded wire 1 is rotated.

[0045] The stranded wire 1 of this embodiment is formed by stranding a plurality of strands having 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 radially taller than the first strands 7. The second strand 5 has two recesses 5b and 5a where 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 substance can be stably collected and transported from the patient's body.

[0046] 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 mechanism of the present invention.

[0047] The second embodiment of the present invention will be described below. The twisted wire 10 of this embodiment is used in an internal retrieval mechanism 100 in which the twisted wire 1 of the first embodiment is used. The common parts are given the same symbols and will not be described.

[0048] As in FIG. 2, the tip of the stranded 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 stranded wire 10 is connected to the rotating shaft of the motor 8.

[0049] Therefore, bodily matter D such as plaque that is cut by the cutter 4c and taken into the inside of 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 FIG. 2) by the rotation of the stranded wire 10.

[0050] As shown in FIG. 5, the stranded wire 10 of this embodiment is formed by stranding a plurality of strands having an approximately circular cross section into a hollow tubular shape so as to form a gap 19 at the center, and 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 radially taller than the first strands 17, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

[0051] 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 its side surface and a nose portion 15x in a region connecting the recesses 15b and 15a, so as to follow the cross-sectional shapes of the two first wires 17a and 17q adjacent to both sides of the second wire 15.

[0052] The second wire 15 differs from the second wire 5 of the first embodiment in the following respects: In other words, the second wire 15 has the recesses 15b and 15a formed on the side of the wire having a substantially circular cross section, whereas the second wire 5 of the first embodiment is configured such that the length of the nose portion 5x is slightly longer than the diameter of the substantially circular shape, and is configured not to be further displaced from the first wires 7a and 7k adjacent to both sides.

[0053] Therefore, although the second wire 15 is slightly inferior to the second wire 5 of the first embodiment in terms of its ability to not shift from the first wire, the recesses 15b and 15a formed in the second wire 15 can be easily formed on the side of the wire having an approximately circular cross-section, making it easier to form the recesses than the second wire 5 of the first embodiment.

[0054] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0055] 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, and the number can be any number that can maintain the second wires 15.

[0056] In addition, in this embodiment, 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, but the two recesses 15b and 15a do not necessarily have 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.

[0057] However, forming the shapes of the two recesses 15b and 15a to conform to the cross-sectional shapes of the two first wires 17a and 17q adjacent to both sides of the second wire 15 can prevent the second wire 15 from shifting out of place from the first wires 17a and 17q when the twisted wire 10 is rotated.

[0058] Furthermore, in this embodiment, the two recesses 15b and 15a have been 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 they can accommodate a portion of the surface of the first wires 17a and 17q.

[0059] However, if the shapes of the two recesses 15a and recess 15a are the same, it is possible to prevent bias and to prevent second wire 15 from shifting from first wires 17a and 17q when twisted wire 10 is rotated.

[0060] The stranded wire 10 of the present embodiment is formed by stranding a plurality of strands having circular cross sections 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 having a radial height greater than the first strands 7. The second strand 15 has two recesses 15b and 15a where 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 strands 17, and by rotating the stranded wire 10, an appropriate amount of a substance can be stably collected and transported from the patient's body.

[0061] 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.

[0062] 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 common parts are given the same symbols and will not be described.

[0063] As in FIG. 2, the tip of the stranded 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 stranded wire 20 is connected to the rotating shaft of the motor 8.

[0064] Therefore, bodily matter 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 20 and is transported in the X direction (see FIG. 2) by the rotation of the stranded wire 20.

[0065] As shown in FIG. 6, the stranded wire 20 of this embodiment is formed by stranding a plurality of strands having an approximately circular cross section into a hollow tubular shape so as to form a gap 29 at 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 radially taller than the first strands 27, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

[0066] As described above, the second wires 25 are taller in the radial direction than the first wires 27, and also have a cross-sectional shape different from that of the first wires 27.

[0067] Specifically, the cross-sectional shape of the second wire 25 has two recesses 25b and 25a on the side surface 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 enlarged diameter portion 25q and enlarged diameter portion 25p.

[0068] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0069] 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, and the number can be any number that can maintain the second wires 25.

[0070] In addition, in this embodiment, 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, but the two recesses 25b and 25a do not necessarily have to be formed to conform to the cross-sectional shapes of the first wires 27a and 27q, and it is sufficient that the recesses 25b and 25a are formed so as to accommodate at least a portion of the surface of the two adjacent first wires 27a and 27q.

[0071] However, forming the shapes of the two recesses 25b and 25a to conform to the cross-sectional shapes of the two first wires 27a and 27q adjacent to both sides of the second wire 25 can prevent the second wire 25 from shifting out of place from the first wires 27a and 27q when the twisted wire 20 is rotated.

[0072] Furthermore, in this embodiment, the two recesses 25b and 25a have been 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 they can accommodate a portion of the surface of the first wires 27a and 27q.

[0073] However, if the shapes of the two recesses 25a and recess 25a are the same, it is possible to prevent bias and to prevent second wire 25 from shifting from first wires 27a and 27q when stranded wire 20 is rotated.

[0074] According to the stranded wire 20 of the present embodiment, a stranded wire is formed by stranding a plurality of wires having a circular cross section into a tubular shape, and the wire includes first wires 27 (27a, 27b, 27c, 27d, 27e, 27f, 27g, 27h, 27j, 27k, 27m, 27n, 27p, 27q) and one second wire 25 having a radial height higher than the first wires 27, and the second wire 25 is intersected by the first wires 27a and The stranded wire 20 has two recesses 25b and 25a where the first wires 27a and 27q abut, and expanded diameter portions 25q and 25p where the recesses 25b and 25a expand in diameter along the first wires 27a and 27k toward the center of the tubular shape in cross-sectional view. Therefore, when the stranded wire 20 is rotated, the second wires 25 will not shift further, and by rotating the stranded wire 20, an appropriate amount of substance can be more stably collected and transported from the patient's body.

[0075] (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.

[0076] 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 common parts are given the same symbols and will not be described.

[0077] As in FIG. 2, the tip of the stranded 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 stranded wire 30 is connected to the rotating shaft of the motor 8.

[0078] Therefore, bodily matter 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 30 and is transported in the X direction (see FIG. 2) by the rotation of the stranded wire 30.

[0079] As shown in FIG. 7, the stranded wire 30 of this embodiment is formed by stranding a plurality of wires having an approximately circular cross section into a hollow tubular shape so as to form a gap 39 at the center, and is composed of thirteen first wires 37 (37a, 37b, 37c, 37d, 37e, 37f, 37g, 37h, 37j, 37k, 37m, 37n, 37p), one second wire 35a that is taller in the radial direction than the first wires 37, and one second wire 35b that is located 180° rotated in cross section from the second wire 35a and is taller in the radial direction than the first wires 37, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

[0080] As described above, the second wires 35a and 35b are taller in the radial direction than the first wires 37, and also have a cross-sectional shape different from that of the first wires 37.

[0081] 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 enlarged diameter portion 35aq and enlarged diameter portion 35ap.

[0082] In addition, 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 enlarged diameter portion 35bq and enlarged diameter portion 35bp.

[0083] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0084] 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, and the number can be any number that can support the second wires 35a and 35b.

[0085] In addition, in this embodiment, the number of second wires 35 has been described as two, but two is merely an example and is not limited to two, and any number can be used as long as a gap G can be secured in which internal matter D such as plaque can be collected and transported.

[0086] 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°. However, 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 the second wires may be arranged in an uneven positional relationship. Any positional relationship is acceptable as long as a gap G is secured in which internal matter D, such as plaque, can be collected and transported.

[0087] Furthermore, in this embodiment, the second wire is described as being a wire 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.

[0088] 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. However, the two recesses 35ab and 35aa do not necessarily have 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 as to accommodate at least a portion of the surfaces of the two adjacent first wires 37a and 37p.

[0089] However, forming the shapes of the two recesses 35ab and 35aa to conform to the cross-sectional shapes of the two first wires 37a and 37p adjacent to either side of the second wire 35a can better prevent the second wire 35a from shifting from the first wires 37a and 37p when the twisted wire 30 is rotated.

[0090] Furthermore, in this embodiment, the two recesses 35ab and 35aa have been 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.

[0091] However, if the shapes of the two recesses 35ab and 35aa are the same, it is possible to prevent bias and to prevent the second strand 35a from shifting from the first strands 37a and 37p when the stranded wire 30 is rotated.

[0092] The above points regarding the second wire 35a also apply to the second wire 35b.

[0093] According to the stranded wire 30 of the present embodiment, a stranded wire is formed by stranding a plurality of wires having a circular cross section into a tubular shape, and the wires include first wires 37 (37a, 37b, 37c, 37d, 37e, 37f, 37g, 37h, 37j, 37k, 37m, 37n, 37p) and two second wires 35a and 35b that are higher in the radial direction than the first wires 37. The second wire 35a has two recesses 35ab and 35aa where the adjacent first wires 37a and 37p abut on each other in a cross section, and the recesses 35ab and 35aa are disposed along the first wires 37a and 37p on the tubular center side in a cross section. The other second strand 35b has two recesses 35bb and 35ba where adjacent first strands 37g and 37f abut in cross section, and expanded diameter portions 35bq and 35bp where recesses 35bb and 35ba expand in cross section along first strands 37g and 37f toward the center of the tubular shape. Therefore, even when strand 30 is rotated, second strands 35a and 35b will not shift, and by rotating strand 30, an appropriate amount of substance can be more stably collected and transported from the patient's body.

[0094] 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.

[0095] The fifth embodiment of the present invention will be described below. The twisted wire 40 of this embodiment is used in the internal retrieval mechanism 100 in which the twisted wire 1 of the first embodiment is used. The common parts are given the same symbols and will not be described.

[0096] As in FIG. 2, the tip of the stranded 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 stranded wire 40 is connected to the rotating shaft of the motor 8.

[0097] Therefore, bodily matter 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 40 and is transported in the X direction (see FIG. 2) by the rotation of the stranded wire 40.

[0098] As shown in FIG. 8, the stranded wire 40 of this embodiment is formed by stranding a plurality of strands having an approximately circular cross section into a hollow tubular shape so as to form a gap 49 at the center, and is composed of twelve 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.

[0099] As described above, the second wires 45a and 45b are taller in the radial direction than the first wires 47, and also have a cross-sectional shape different from that of the first wires 47.

[0100] Specifically, the cross-sectional shape of the second wire 45a has a single recess 45aa on the side surface so as to conform to the cross-sectional shape of a single first wire 47n adjacent to one side of the second wire 45a, and the cross-sectional shape of the second wire 45b has a single recess 45ba on the side surface so as to conform to the cross-sectional shape of a single first wire 47a adjacent to one side of the second wire 45b.

[0101] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0102] 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 the number can be any number that can support the second wires 45a and 45b.

[0103] 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, and any number of second wires may be adjacent to each other in a row as long as a gap G is secured in which intracorporeal matter D such as plaque can be collected and transported.

[0104] 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 wires 45a and 45b. However, 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 as to accommodate at least a portion of the surface of the two adjacent first wires 47n and 47a.

[0105] However, forming the shapes of the two recesses 45ba and 45aa 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 can prevent the second wires 45a and 45b from shifting out of place from the first wires 47n and 47a when the twisted wire 40 is rotated.

[0106] 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 recess 45ba and the shape of recess 45aa may be different as long as they can accommodate a portion of the surface of the first wires 47n and 47a.

[0107] However, if the shape of the two recesses 45ba and the shape of the recess 45aa are the same, it is possible to prevent bias and to prevent the second wires 45a and 45b from shifting from the first wires 47n and 47a when the twisted wire 40 is rotated.

[0108] The stranded wire 40 of the present embodiment is formed by stranding a plurality of strands having circular cross sections 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 each have one recess 45aa with which the adjacent first strands 47n abut in a cross-sectional view, and one recess 45ba with which 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 a substance can be more stably collected and transported from the patient's body.

[0109] 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.

[0110] The sixth embodiment of the present invention will be described below. The twisted wire 50 of this embodiment is used in the internal retrieval mechanism 100 in which the twisted wire 1 of the first embodiment is used. The common parts are given the same symbols and will not be described.

[0111] As in FIG. 2, the tip of the stranded 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 stranded wire 50 is connected to the rotating shaft of the motor 8.

[0112] Therefore, bodily matter 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 50 and is transported in the X direction (see FIG. 2) by the rotation of the stranded wire 50.

[0113] As shown in FIG. 9, the stranded wire 50 of this embodiment is formed by stranding a plurality of strands that are annular in cross section into a hollow tube so as to form a gap 59 at the center, and is composed of fifteen 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 radially taller than the first strands 57, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

[0114] As described above, the second wire 55 has a higher radial height than the first wire 57, and also has a cross-sectional shape different from that of 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 a region connecting the line segments 55a and 55b, and a circular portion 55c that is continuous with the line segments 55a and 55b.

[0115] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0116] 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, and the number can be any number that can support the second wires 55.

[0117] In addition, in this embodiment, the cross-sectional shape of the first wire 57 is an annular sector shape, but this is not limited to an annular sector shape, and it may be a generally rectangular cross-sectional shape known as a flat wire, which will be described later, or it may be a circular cross-sectional shape or an elliptical cross-sectional shape.

[0118] According to the stranded wire 50 of the present embodiment, the stranded wire is formed by stranding a plurality of 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 having a radial height greater than the first strands 57. The second strand 55 has two line segments 55a and 55b that are substantially parallel to the tubular center line CL5 in a cross-sectional view, and abuts against 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 a substance can be more stably collected and transported from the patient's body.

[0119] 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.

[0120] 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 common parts are given the same symbols and will not be described.

[0121] As in FIG. 2, the tip of the stranded 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 stranded wire 60 is connected to the rotating shaft of the motor 8.

[0122] Therefore, bodily matter 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 FIG. 2) by the rotation of the stranded wire 60.

[0123] As shown in FIG. 10, the stranded wire 60 of this embodiment is formed by stranding a plurality of strands having a generally rectangular cross section into a hollow tube shape so as to form a gap 69 at 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 having a generally rectangular cross section and a radial height that is taller than the first strands 67, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

[0124] Specifically, the cross-sectional shape of the second wire 65 is composed of two line segments 65a and 65b that are approximately parallel to a 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.

[0125] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0126] 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, and the number can be any number that can support the second wires 65.

[0127] In addition, in this embodiment, the first wire 67 has a generally rectangular shape in cross section, but this is not limited to a generally rectangular shape, and may be an annular sector shape in cross section as described above, or may be a circular shape or an elliptical shape in cross section.

[0128] The stranded wire 60 of the present embodiment is a stranded wire formed by stranding 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 is in contact with the adjacent first strands 67a and 67r on the two line segments 65a and 65b. Therefore, when the stranded wire 60 is rotated, the second strand 65 will not shift, and by rotating the stranded wire 60, an appropriate amount of substance can be more stably collected and transported from the patient's body.

[0129] Furthermore, according to the stranded wire 60 of this embodiment, the second wires 65 have a generally rectangular cross section, so that a stranded wire in which the second wires 65 do not shift can be easily manufactured.

[0130] 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.

[0131] 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 common parts are given the same symbols and will not be described.

[0132] As in FIG. 2, the tip of the stranded 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 stranded wire 70 is connected to the rotating shaft of the motor 8.

[0133] Therefore, bodily matter 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 70 and is transported in the X direction (see FIG. 2) by the rotation of the stranded wire 70.

[0134] As shown in FIG. 11, the twisted wire 70 of this embodiment is formed by twisting a plurality of wires having a generally rectangular cross section into a hollow tube shape so as to form a gap 79 at the center, and is composed of 15 first wires 77 (77a, 77b, 77c, 77d, 77e, 77f, 77g, 77h, 77j, 77k, 77m, 77n, 77p, 77q, 77r) and one second wire 75 having a generally square cross section that is taller in the radial direction than the first wires 77, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

[0135] Specifically, the cross-sectional shape of the second wire 75 is composed of two line segments 75a and 75b that are approximately parallel to a 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.

[0136] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0137] 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, and the number can be any number that can maintain the second wires 75.

[0138] In addition, in this embodiment, the first wire 77 has a generally rectangular shape in cross section, but this is not limited to a generally rectangular shape, and may be an annular sector shape in cross section as described above, or may be a circular shape or an elliptical shape in cross section.

[0139] The stranded wire 70 of the present embodiment is formed by stranding 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 is in contact with the adjacent first strands 77a and 77r on the two line segments 75a and 75b. Therefore, when the stranded wire 70 is rotated, the second strand 75 will not shift, and by rotating the stranded wire 70, an appropriate amount of substance can be more stably collected and transported from the patient's body.

[0140] Furthermore, according to the stranded wire 70 of this embodiment, the second wires 75 have a generally square cross section, so that a stranded wire in which the second wires 75 do not shift can be easily manufactured.

[0141] 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.

[0142] 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 common parts are given the same symbols and will not be described.

[0143] As in FIG. 2, the tip of the stranded 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 stranded wire 80 is connected to the rotating shaft of the motor 8.

[0144] Therefore, bodily matter 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 80 and is transported in the X direction (see FIG. 2) by the rotation of the stranded wire 80.

[0145] As shown in FIG. 12, the stranded wire 80 of this embodiment is formed by stranding a plurality of wires having an annular sector shape in cross section into a hollow tube so as to form a gap 89 at the center, and is composed of 14 first wires 87 (87a, 87b, 87c, 87d, 87e, 87f, 87g, 87h, 87j, 87k, 87m, 87n, 87p, 87q), one second wire 85a having a generally square shape in cross section and a higher radial height than the first wires 87, and one second wire 85b located 180° rotated in cross section from the second wire 85a and having a higher radial height than the first wires 87, and is configured to be rotatable inside the catheter 3 as the motor 8 rotates.

[0146] Specifically, the cross-sectional shape of the second wire 85a is 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.

[0147] In addition, the cross-sectional shape of the second wire 85b is specifically 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.

[0148] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0149] 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, and the number can be any number that can support the second wires 85a and 85b.

[0150] In addition, in this embodiment, the number of second wires 85 has been described as two, but two is merely an example and is not limited to two, and any number can be used as long as a gap G can be secured in which internal matter D such as plaque can be collected and transported.

[0151] 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 the second wires may be arranged in an even positional relationship, such as a positional relationship with a rotation angle of 120° when there are three second wires, or a positional relationship with a rotation angle of 90° when there are four second wires, or the second wires may be arranged in an uneven positional relationship. Any positional relationship is acceptable as long as a gap G is secured in which internal matter D, such as plaque, can be collected and transported.

[0152] In addition, in this embodiment, the cross-sectional shape of the first wire 87 is an annular sector, but this is not limited to an annular sector, and may be approximately rectangular, circular, or elliptical in cross section.

[0153] According to the stranded wire 80 of the present embodiment, the 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 generally square in cross section and have a radial height greater than the first strands 87. The second strand 85a has two line segments 85ab and 85aa that are generally parallel to the tubular center line CL8 in cross section, and abuts against the adjacent first strands 87a and 87q on the two line segments 85ab and 85aa. Therefore, 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 a substance can be more stably collected and transported from the patient's body.

[0154] 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 will 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.

[0155] Furthermore, according to the stranded wire 80 of this embodiment, the second element wires 85a and 85b have a substantially square cross section, so that a stranded wire in which the second element wires 85a and 85b do not shift can be easily manufactured.

[0156] 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 system of the present invention.

[0157] The tenth embodiment of the present invention will be described below. The twisted wire 90 of this embodiment is used in an internal retrieval mechanism 100 in which the twisted wire 1 of the first embodiment is used. The common parts are given the same symbols and will not be described.

[0158] As in FIG. 2, the tip of the stranded 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 stranded wire 90 is connected to the rotating shaft of the motor 8.

[0159] Therefore, bodily matter 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 90 and is transported in the X direction (see FIG. 2) by the rotation of the stranded wire 90.

[0160] As shown in FIG. 13, the stranded wire 90 of this embodiment is formed by stranding a plurality of strands that are annular in cross section into a hollow tube so as to form a gap 99 at the center, and is composed of thirteen 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.

[0161] Specifically, the cross-sectional shape of the second wire 95a is composed of one line segment 95aa that is approximately parallel to a center line CL9a from a 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 connecting the line segment 95aa and the circular portion 95ac.

[0162] In addition, the cross-sectional shape of the second wire 95b is specifically 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 connecting the line segment 95ba and the circular portion 95bc.

[0163] 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, cobalt alloy, etc., but stainless steel is used in this embodiment.

[0164] 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, and the number can be any number that can support the second wires 95a and 95b.

[0165] In addition, in this embodiment, the number of second wires 95 has been described as two, but two is merely an example and is not limited to two, and any number can be used as long as a gap G can be secured in which internal body matter D such as plaque can be collected and transported.

[0166] In addition, in this embodiment, the cross-sectional shape of the first wire 97 is an annular sector, but this is not limited to an annular sector, and may be approximately rectangular, circular, or elliptical in cross section.

[0167] The stranded wire 90 of the present embodiment is formed by stranding a plurality of strands into a tubular shape, and the strands include 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 taller in the radial direction than the first strands 97. The second strands 95a have one line segment 95aa that is substantially parallel to the tubular center line CL9a in a cross-sectional view, and abut against the adjacent first strands 97p on the one line segment 95aa. Therefore, when the stranded wire 90 is rotated, the second strands 95a will not shift, and by rotating the stranded wire 90, an appropriate amount of a substance can be more stably collected and transported from the patient's body.

[0168] In addition, the second wire 95b has a 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 line segment 95ba. Therefore, when the stranded wire 90 is rotated, the second wire 95b will not shift, and by rotating the stranded wire 90, an appropriate amount of substance can be more stably collected and transported from the patient's body. [Explanation of symbols]

[0169] 1,10,20,30,40,50,60,70,80,90...Twisted wire 3. Catheter (housing) 4···Cutter assembly 4c...Cutter 5,15,25,35a,35b,45a,45b,55,65,75,85a,85b,95a,95b...Second strand 5a, 5b, 15a, 15b, 25a, 25b, 35aa, 35ab, 35ba, 35bb, 45aa, 45ba... recess 6...Gripping part 7,17,27,37,47,57,67,77,87,97...First wire 8. Motor 25p, 25q, 35ap, 35aq, 35bp, 35bq... Expanded diameter part 55a, 55b, 65a, 65b, 75a, 75b, 85aa, 85ab, 85ba, 85bb, 95aa, 95ba... Line segments 100... Internal recovery mechanism CL5, CL6, CL7, CL8, CL9a, CL9b...center line D...Substances in the body G... air gap

Claims

1. 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.

2. 2. The stranded wire according to claim 1, wherein at least one of the second strands has two recesses on a surface where the second strand abuts against the adjacent first strand.

3. 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.

4. 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. 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.

6. 6. The stranded wire according to claim 4 or 5, wherein the at least one second strand has a cross section that is substantially square or rectangular.

7. 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:

Images