The disclosed embodiments relate to a guide wire, and a method for manufacturing the guide wire.
There is known a guide wire used for inserting a catheter or the like into a blood vessel. In such a guide wire, to improve selectivity for blood vessels and smoothly lead the guide wire to a target site in the blood vessel, a shape such as a small curve is provided to a distal end portion of the guide wire in some cases. For example, Patent Literatures 1 to 5 disclose a guide wire in which a ribbon (shaping ribbon) made of stainless steel is joined to a distal end of a long shaft (wire main body) made of a nickel-titanium alloy to facilitate shaping of the distal end portion.
Herein, the long shaft and the ribbon are joined by soldering or brazing between the long shaft and the ribbon arranged adjacent to each other. Herein, the nickel-titanium alloy constituting the long shaft and the stainless steel constituting the ribbon significantly differ from each other in a strain amount leading to breaking. Thus, in the guide wires described in Patent Literatures 1 to 5 have had a problem that, when a load (e.g., tensile load) is applied to a joint part between the long shaft and the ribbon, the nickel-titanium alloy having a large strain amount is elongated, and the long shaft is detached from the joint part.
Such a problem is not limited to a vascular system, and is common to guide wires to be inserted into various organs in a human body, such as a lymphatic system, a biliary system, a urinary system, a respiratory system, a digestive system, a secretory gland, and a reproductive organ. In addition, such a problem is not limited to the guide wire including a long shaft made of a nickel-titanium alloy and a ribbon made of stainless steel, and is common to guide wires prepared by joining a plurality of core shafts made of materials that significantly differ from each other in the strain amount leading to breaking.
The disclosed embodiments have been made to solve the above problems, and to prevent detachment destruction on the joint part caused by applying a load to the guide wire including a plurality of core shafts joined together.
The disclosed embodiments were made to solve at least one or more of a part of the aforementioned problems, and can be achieved as the following aspects.
(1) According to one aspect of the disclosed embodiments, a guide wire is provided. The guide wire includes a first core shaft that is made of a superelastic material, and a second core shaft that is made of a material more plastically deformable than the first core shaft and is joined to a distal end portion of the first core shaft. On the distal end portion to which the second core shaft is joined in the first core shaft, a breaking elongation attributed to a tensile load is shorter compared to portions on a proximal end side with respect to the distal end portion. This “breaking elongation” is also referred to as a “strain amount” leading to breaking.
According to this configuration, on the distal end portion to which the second core shaft is joined in the first core shaft made of the superelastic material, the breaking elongation attributed to the tensile load is shorter compared to the portions on the proximal end side with respect to the distal end portion. Thereby, the elongation of the first core shaft can be prevented on the joint part, so that the interface detachment of the first core shaft from the joint part can be prevented. As a result, this configuration makes it possible to prevent the detachment destruction of the joint part caused by applying a tensile load to the guide wire including the jointed first and second core shafts.
(2) In the guide wire according to the above aspect, an amount of the breaking elongation attributed to the tensile load on the distal end portion of the first core shaft may be closer to an amount of a breaking elongation attributed to a tensile load on the second core shaft, compared to the portions on the proximal end side with respect to the distal end portion.
According to this configuration, on the distal end portion to which the second core shaft is joined in the first core shaft made of the superelastic material, an amount of the breaking elongation attributed to the tensile load can be closer to an amount of the breaking elongation attributed to the tensile load on the second core shaft compared to the portions on the proximal end side with respect to the distal end portion, so that the interface detachment of the first core shaft from the joint part between the first core shaft and the second core shaft can be prevented.
(3) In the guide wire according to the above aspects, a nanoindentation hardness on the distal end portion of the first core shaft may be higher compared to the portions on the proximal end side with respect to the distal end portion.
According to this configuration, on the distal end portion to which the second core shaft is joined in the first core shaft made of the superelastic material, the nanoindentation hardness is higher compared to the portions on the proximal end side with respect to the distal end portion. That means, according to this configuration, a superelasticity of the superelastic material can be eliminated or reduced on the distal end portion to which the second core shaft is joined in the first core shaft. Thereby, the elongation of the first core shaft can be prevented on the joint part, so that the interface detachment of the first core shaft from the joint part can be prevented.
(4) In the guide wire according to the above aspects, the nanoindentation hardness on the distal end portion of the first core shaft may be not equal to or greater than 1.1 times the nanoindentation hardness of the portions on the proximal end side with respect to the distal end portion.
According to this configuration, when the nanoindentation hardness on the distal end portion of the first core shaft is equal to or greater than 1.1 times the nanoindentation hardness of the portions on the proximal end side with respect to the distal end portion, the superelasticity of the superelastic material can be eliminated or reduced.
(5) In the guide wire according to the above aspects, the nanoindentation hardness on the distal end portion of the first core shaft may be 4500 N/mm2 or higher.
According to this configuration, when the nanoindentation hardness on the distal end portion of the first core shaft is 4500 N/mm2 or higher, the superelasticity of the superelastic material can be eliminated or reduced in a way that.
(6) In the guide wire according to the above aspects, the first core shaft further has a reduced diameter portion whose outer diameter decreases from the proximal end side toward the distal end side, wherein the distal end portion of the first core shaft may be connected to a distal end of the reduced diameter portion.
According to this configuration, since the first core shaft further has the reduced diameter portion whose outer diameter decreases from the proximal end side toward the distal end side, a rigidity of the first core shaft can be gradually changed on the reduced diameter portion. As a result, it is possible to provide a guide wire whose flexibility gradually increases from the proximal end side toward the distal end side.
(7) In the guide wire according to the above aspects, a gradually-changed portion whose nanoindentation hardness gradually increases from the proximal end side toward the distal end side may be disposed on the distal end portion of the reduced diameter portion. According to this configuration, the gradually-changed portion whose nanoindentation hardness gradually increases from the proximal end side toward the distal end side is disposed on the distal end portion of the reduced diameter portion. Thereby, the superelasticity of the first core shaft can be gradually decreased on the gradually-changed portion.
(8) According to one aspect of the disclosed embodiments, a method for manufacturing a guide wire is provided. This manufacturing method includes: subjecting a distal end portion of a first core shaft made of a superelastic material, to first processing using at least one method of pressing, swaging, and drawing; and joining a second core shaft made of a material that is more plastically deformable than the first core shaft, to the distal end portion subjected to the first processing.
According to this configuration, the method for manufacturing the guide wire includes processing the distal end portion of the first core shaft made of the superelastic material, using at least one method of pressing, swaging, and drawing. Thus, on the distal end portion of the first core shaft, a breaking elongation can be easily be shortened and a nanoindentation hardness can be easily increased compared to the portions on the proximal end side with respect to the distal end portion by pressing, swaging, or drawing. In addition, an amount of the breaking elongation on the distal end portion of the first core shaft can be closer to an amount of the breaking elongation attributed to a tensile load on the second core shaft, compared to the portions on the proximal end side with respect to the distal end portion.
Note that the disclosed embodiments can be achieved in various aspects, e.g., in a form of a core shaft product composed of a plurality of core shafts used for a guide wire, a method for manufacturing the guide wire, or the like.
In
The first core shaft 10 is a tapered long member having a large diameter on the proximal end side and a small diameter on the distal end side. The first core shaft 10 is made of a superelastic material, e.g., a NiTi (nickel-titanium) alloy, or an alloy of NiTi and another metal. The first core shaft 10 has a distal end portion 11, a first reduced diameter portion 12, e.g., a first variable diameter portion, a first large diameter portion 15, a second reduced diameter portion 16, e.g., a second variable diameter portion, and a second large diameter portion 17, in this order from the distal end side to the proximal end side. In particular, the first reduced diameter portion 12 may have a diameter that increases, e.g., continuously, from a diameter of the distal end portion 11 to a diameter of the first large diameter portion 15, and the second reduced diameter portion 16 may have a diameter that increases, e.g., continuously, from a diameter of the first large diameter portion 15 to a diameter of the second large diameter portion 17. An outer diameter and a length of each portion can be arbitrarily determined. The first core shaft 10 may be made of a pseudoelastic NiTi alloy or the like.
The distal end portion 11 is disposed on the distal end side of the first core shaft 10 and is a part to which the second core shaft 30 described later is joined. The distal end portion 11 has the smallest transverse sectional area compared to those of the other portions (first reduced diameter portion 12, first large diameter portion 15, etc.) of the first core shaft 10. The distal end portion 11 has an almost elliptical transverse section as illustrated in
The first reduced diameter portion 12 is disposed between the distal end portion 11 and the first large diameter portion 15. The first reduced diameter portion 12 has an almost truncated cone shape with an outer diameter decreasing from the proximal end side toward the distal end side. The first large diameter portion 15 is disposed between the first reduced diameter portion 12 and the second reduced diameter portion 16. The first large diameter portion 15 has an almost cylindrical shape with a substantially constant outer diameter larger than the height L2 of the distal end portion 11. The second reduced diameter portion 16 is disposed between the first large diameter portion 15 and the second large diameter portion 17. The second reduced diameter portion 16 has an almost truncated cone shape with an outer diameter decreasing from the proximal end side toward the distal end side. The second large diameter portion 17 is disposed on the proximal end side of the first core shaft 10. The second large diameter portion 17 has an almost cylindrical shape with a substantially constant outer diameter larger than the other portions (second reduced diameter portion 16, first large diameter portion 15, etc.) of the first core shaft 10.
In the first core shaft 10 according to the first embodiment, a breaking elongation of the distal end portion 11 is shorter compared to the portions (i.e., first reduced diameter portion 12, first large diameter portion 15, second reduced diameter portion 16, and second large diameter portion 17) on the proximal end side with respect to the distal end portion 11. A correlation on the distal end portion 11 is closer to the correlation shown in Table 1, compared to the portions on the proximal end side with respect to the distal end portion 11.
As an example, in a first core shaft composed of a superelastic NiTi, a nanoindentation hardness of the distal end portion 11 according to the first embodiment is 4500 N/mm2, and the nanoindentation hardness of the first reduced diameter portion 12, the first large diameter portion 15, the second reduced diameter portion 16, and the second large diameter portion 17 is each 4000 N/mm2. In other words, the nanoindentation hardness of the distal end portion 11 is not less than 1.1 times the nanoindentation hardness of the portions on the proximal end side with respect to the distal end portion 11. The method for measuring the hardness is described later in
Outer faces of the distal end portion 11, the first reduced diameter portion 12, and the first large diameter portion 15 may be covered with the coil body 20 described below. On the other hand, the second reduced diameter portion 16 and the second large diameter portion 17 may not be covered with the coil body 20 and are exposed from the coil body 20. An operator uses the second large diameter portion 17 for gripping the guide wire 1.
The coil body 20 may have an almost hollow cylindrical shape formed by spirally winding a wire 21 around the first core shaft 10 and the second core shaft 30. The coil body 20 may be a single-thread coil formed by winding one wire in a single-thread pattern, a multi-thread coil formed by winding a plurality of wires in a multi-thread pattern, a single-thread strand coil formed by winding, in a single-thread pattern, a strand composed of a plurality of wires twisted together, or a multi-thread strand coil formed by winding, in a multi-thread pattern, a plurality of strands composed of a plurality of wires twisted together. For the coil body 20, a wire diameter of the wire 21 and an average diameter of the coil (an average diameter of the outer diameter and inner diameter of the coil body 20) can be arbitrarily determined.
The wire 21 can be made of, for example, a stainless steel alloy such as SUS304 and SUS316, a superelastic alloy such as NiTi alloy, a piano wire, a radiolucent alloy such as nickel-chromium alloy and cobalt alloy, gold, platinum, tungsten, or a radiopaque alloy such as an alloy containing any of these elements (e.g. a platinum-nickel alloy). The wire 21 may be formed of a known material other than the above materials.
The second core shaft 30 may be a long member extending from the proximal end side toward the distal end side. The second core shaft 30 is made of a material that is more plastically deformable than the first core shaft 10, e.g., a stainless steel alloy such as SUS304 and SUS316. The second core shaft 30 is also referred to as “ribbon”. The second core shaft 30 has a distal end portion 31, an intermediate portion 32, and a proximal end portion 33 in this order from the distal end side to the proximal end side. An outer diameter and a length of each portion can be arbitrarily determined.
The distal end portion 31 is disposed on the distal end side of the second core shaft 30 and is fixed by the distal fixation portion 51. The intermediate portion 32 is positioned between the distal end portion 31 and the proximal end portion 33 of the second core shaft 30. The proximal end portion 33 is disposed on the proximal end side of the second core shaft 30 and is joined to the first core shaft 10.
Similarly to the distal end portion 11 of the first core shaft 10, the second core shaft 30 may have a flat shape with an almost elliptical transverse section, and the transverse sectional shape is not particularly limited.
As illustrated in
As illustrated in
The distal fixation portion 51 is positioned on the distal end portion of the guide wire 1 and integrally holds the distal end portion 31 of the second core shaft 30 and the distal end portion of the coil body 20. The distal fixation portion 51 can be made of any joining agent, e.g., a metal solder such as silver solder, gold solder, zinc, Sn—Ag alloy, Au—Sn alloy, and the like, or an adhesive such as an epoxy adhesive and the like. The proximal fixation portion 52 is disposed on the proximal end portion of the first large diameter portion 15 of the first core shaft 10, and integrally holds the first core shaft 10 and the proximal end portion of the coil body 20. The proximal fixation portion 52 can be made of any joining agent, similarly to the distal fixation portion 51. A joining agent used for the proximal fixation portion 52 and a joining agent used for the distal fixation portion 51 may be the same or different.
The intermediate fixation portion 61 integrally holds the coil body 20 and the first core shaft 10 in the vicinity of an intermediate portion of the coil body 20 in the axis line O direction. The intermediate fixation portion 61 can be made of any joining agent, similarly to the distal fixation portion 51. A joining agent used for the intermediate fixation portion 61 and a joining agent used for the distal fixation portion 51 may be the same or different. Although the one intermediate fixation portion 61 was illustrated in
This guide wire 1 can be manufactured as described below, for example. First, the first core shaft 10 made of a superelastic material and the second core shaft 30 made of a material that is more plastically deformable than the first core shaft 10 are prepared. The first core shaft 10 has an almost cylindrical (i.e., unflat) distal end portion 11 having a substantially constant outer diameter. Next, the distal end portion 11 of the first core shaft 10 is pressed to prepare the first core shaft 10 having the distal end portion 11 with a shorter breaking elongation compared to the proximal end portion of the first core shaft. Specifically, the distal end portion 11 of the first core shaft 10 has at least one of the properties of the flat shape, the short breaking elongation, and the high nanoindentation hardness explained in
<Example of Effect>
As described above, in the guide wire 1 according to the first embodiment, the distal end portion 11 to which the second core shaft 30 is joined in the first core shaft 10 made of a superelastic material has a shorter breaking elongation attributed to the tensile load compared to the portions (first reduced diameter portion 12, first large diameter portion 15, second reduced diameter portion 16, and second large diameter portion 17) on the proximal end side with respect to the distal end portion. Thereby, the elongation of the first core shaft 10 can be prevented on the joint part JP, so that the interface detachment of the first core shaft 10 from the joint part JP can be prevented. As a result, according to the first embodiment, the detachment destruction of the joint part JP caused by applying a tensile load to the guide wire 1 including the jointed first and second core shafts 10 and 30 may be prevented.
In the guide wire 1 according to the first embodiment, on the distal end portion 11 to which the second core shaft 30 is joined in the first core shaft 10 made of a superelastic material, an amount of the breaking elongation attributed to the tensile load is closer to an amount of the breaking elongation attributed to the tensile load on the second core shaft 30, compared to the portions on the proximal end side with respect to the distal end portion 11. Thereby, the difference in the amount of the elongation between the first core shaft 10 and the second core shaft 30 on the joint part JP can be reduced, so that the interface detachment of the first core shaft 10 from the joint part JP can be prevented.
In the guide wire 1 according to the first embodiment, the distal end portion 11 to which the second core shaft 30 is joined in the first core shaft 10 made of a superelastic material has a higher nanoindentation hardness compared to the portions on the proximal end side with respect to the distal end portion 11. That means, according to the first embodiment, a superelasticity of the superelastic material can be eliminated or reduced on the distal end portion 11 to which the second core shaft 30 is joined in the first core shaft 10. Thereby, the “elongation” of the first core shaft 10 on the joint part JP due to the superelasticity can be reduced, and the interface detachment of the first core shaft 10 from the joint part JP can be prevented.
In the guide wire 1 according to the first embodiment, since the first core shaft 10 further has the first reduced diameter portion 12 whose outer diameter decreases from the proximal end side toward the distal end side, a rigidity of the first core shaft 10 can be gradually changed on the first reduced diameter portion 12. As a result, it is possible to provide the guide wire 1 whose flexibility gradually increases from the proximal end side toward the distal end side. Furthermore, the method for manufacturing the guide wire 1 includes pressing the distal end portion 11 of the first core shaft 10 made of a superelastic material. Thus, on the distal end portion 11 of the first core shaft 10, the breaking elongation attributed to the tensile load can be easily decreased and the nanoindentation hardness can be easily increased compared to the portions on the proximal end side with respect to the distal end portion 11, by pressing. In addition, on the distal end portion 11 of the first core shaft 10, the amount of the breaking elongation attributed to the tensile load can be closer to the amount of the breaking elongation attributed to the tensile load on the second core shaft 30, compared to the portions on the proximal end side with respect to the distal end portion 11.
<Test Result>
Withe reference to
Processing rate=1·(width L12/height L22)×100 (1)
A sample S3 of the first core shaft is pressed to have a distal end portion 113 that is flatter than the sample S2. The distal end portion 113 has an almost elliptical transverse section, and 25% of processing rate. Similar to the sample S2, the processing rate is determined using the above equation (1). A sample S4 of the first core shaft is pressed to have a distal end portion 114 that is flatter than the sample S3. The distal end portion 114 has an almost elliptical transverse section, and 40% of processing rate. Similar to the sample S2, the processing rate is determined using the above equation (1).
Although the plateau region R2 substantially disappeared in the sample S2 with 8% processing rate, the results for the amount of increase in the strain attributed to the tensile load and the strain leading to the breaking point BP (breaking elongation) were similar to those in the sample S1 without pressing. On the other hand, in the sample S3 with 25% processing rate, the plateau region R2 disappeared, and additionally the strain leading to the breaking point BP (breaking elongation) decreased compared to the sample S1 without pressing. In the sample S4 with 40% processing rate, the plateau region R2 disappeared, and additionally the strain leading to the breaking point BP (breaking elongation) further decreased compared to the sample S1 without pressing. The above results elucidated that pressing of the distal end portion 11 of the first core shaft 10 made it possible to eliminate or reduce the superelasticity of the distal end portion 11 and decrease the strain leading to the breaking point BP (i.e., the breaking elongation can be shortened). In other words, the “elongation” of the distal end portion 11 caused by the superelasticity of the distal end portion 11 may be prevented by pressing the distal end portion 11 of the first core shaft 10.
Although not illustrated in
Thus, in the samples S3 or S4 with pressing, change in the strain amount [%] leading to the breaking attributed to the tensile load [N] is closer to change in the strain amount [%] leading to the breaking attributed to the tensile load [N] of the second core shaft 30, compared to the sample S1 without pressing or the sample S2 with a low degree of pressing.
With reference to
A hardness measuring method will be explained. The hardness measurement was conducted using an ultrafine indentation hardness tester ENT-1100b and a Berkovich indenter manufactured by ELIONIX INC. In this measurement, an indentation load of the indenter was set to 100 mN, and the indentation speed was set to 10 mN/sec.
As illustrated in
The test results illustrated in
In this way, the distal end portion 11A of the first core shaft 10A may have an almost polygonal transverse section such as an almost square shape and an almost rectangular shape. This guide wire 1A according to the second embodiment can also exhibit a similar effect to the first embodiment. Furthermore, in the guide wire 1A according to the second embodiment, an area of a part where the first core shaft 10A and the second core shaft 30 are adjacent to each other can be enlarged, so that a joining strength between the first core shaft 10A and the second core shaft 30 can be improved. The pressing is not necessarily performed from two directions, and may be performed from multiple directions.
Thus, the distal end portion 11B of the first core shaft 10B may have an almost perfectly circular transverse sectional shape, and a high nanoindentation hardness, by swaging or drawing. In this case, the first reduced diameter portion 12 may be decreased in diameter toward the distal end by swaging or drawing to form the distal end portion 11B. This guide wire 1B according to the third embodiment can also exhibit a similar effect to the first embodiment. Furthermore, in the guide wire 1B according to the third embodiment, a processing rate of the first reduced diameter portion 12 gradually increases from the proximal end side toward the distal end side, so that a breaking elongation gradually decreases and the nanoindentation hardness gradually increases on the distal end portion 11B.
Thus, the configuration of the first core shaft 10C can be variously modified, and the first core shaft 10C may include the first reduced diameter portion 12C having the gradually-changed portion 121. A range (length in the axis line O direction) where the gradually-changed portion 121 is formed can be arbitrarily determined, and the gradually-changed portion 121 may not be a part on the distal end side explained in
The covering portion 40 may be a single-thread coil formed using one wire, or a multi-thread coil formed by winding a plurality (e.g., eight) of wires in a multi-thread pattern, or a tubular member made of a resin or a metal formed into a tubular shape.
The first core shaft 10E does not include the distal end portion 11, the first reduced diameter portion 12, the first large diameter portion 15, the second reduced diameter portion 16, and the second large diameter portion 17 explained in the first embodiment, but has an almost cylindrical shape with a substantially constant outer diameter throughout the axial line O direction. In the first core shaft 10E, the distal end portion to which the second core shaft 30E is joined has a higher nanoindentation hardness and a smaller strain amount leading to the breaking, compared to the portions on the proximal end side with respect to the distal end portion. The nanoindentation hardness and the strain amount leading to the breaking on the distal end portion of the first core shaft 10E can be adjusted, e.g., by the aforementioned pressing. The second core shaft 30E does not include the distal end portion 31, the intermediate portion 32, and the proximal end portion 33 explained in the first embodiment, but has an almost cylindrical shape with a substantially constant outer diameter throughout the axial line O direction.
As described above, a configuration of at least one of the first core shaft 10E and the second core shaft 30E can be variously changed, and at least a part of each of the aforementioned portions (distal end portion 11, first reduced diameter portion 12, first large diameter portion 15, second reduced diameter portion 16, second large diameter portion 17, distal end portion 31, intermediate portion 32, and proximal end portion 33) may be omitted. This guide wire 1E according to the sixth embodiment can also exhibit a similar effect to the first embodiment.
As described above, the configuration of the second core shaft 30F can be variously modified, and at least a part of the distal end portion 31, the intermediate portion 32, and the proximal end portion 33F may have an almost polygonal transverse section, such as an almost square shape and an almost rectangular shape. This guide wire 1F according to the seventh embodiment can also exhibit a similar effect to the first embodiment. Furthermore, in the guide wire 1F according to the seventh embodiment, an area of a part where the first core shaft 10B and the second core shaft 30F are adjacent to each other can be enlarged, so that a joining strength between the first core shaft 10B and the second core shaft 30F can be improved.
The disclosed embodiments are not limited to the above embodiments, and may be implemented in various modes without departing from the gist of the disclosed embodiments. For example, the following modifications can also be applied.
In the first to seventh embodiments, the configurations of the guide wires 1 and 1A to 1F have been illustrated. However, the configuration of the guide wire can be variously modified. For example, the guide wires according to the above embodiments have been explained as medical appliances used for inserting a catheter into a blood vessel, but the guide wire may be configured to be inserted into various organs in a human body, such as a lymphatic system, a biliary system, a urinary system, a respiratory system, a digestive system, a secretory gland, and a reproductive organ. For example, the guide wire may be configured such that the whole first core shaft is covered with the coil body without the second reduced diameter portion and the second large diameter portion. For example, the guide wire may be productized such that the distal end side is previously curved.
In the above first to seventh embodiments, the configurations of the first core shafts 10 and 10A to 10C, 10E and the configurations of the second core shafts 30, 30E, and 30F were illustrated. However, the configurations of the first and second core shafts can be variously modified. For example, the nanoindentation hardness on the distal end portion of the first core shaft may be not less than 1 time and less than 1.1 times the nanoindentation hardness of the portions on the proximal end side with respect to the distal end portion. This configuration also makes it possible to reduce the superelasticity of the distal end portion of the first core shaft by the difference in the nanoindentation hardness, so that the detachment destruction of the joint part caused by a load on the guide wire can be prevented. In addition, for example, the distal end portion of the first core shaft may have a nanoindentation hardness of lower than 4500 N/mm2.
For example, the distal end portion of the first core shaft may have an almost truncated cone shape, similarly to the first reduced diameter portion. For example, the distal end portion of the first core shaft may be pressed. For example, the first core shaft may be formed by joining a plurality of members having different nanoindentation hardness. In this case, the pressing on the distal end portion of the first core shaft may be omitted.
For example, the proximal end portion of the second core shaft may be pressed only in one direction (e.g., Z-axis direction) to have an almost elliptical transverse section similarly to the distal end portion of the first core shaft according to the first embodiment. For example, in the joint part JP (
In the aforementioned first to seventh embodiments, some examples of the configuration of the coil body 20 have been described. However, the configurations of the coil body can be variously modified. For example, the coil body may have a dense winding configuration with no gap between adjacent wires, a coarse winding configuration with gaps between adjacent wires, or a configuration in which the dense winding and the coarse winding are combined. The coil body may, for example, have a resin layer coated with a hydrophobic resin material, a hydrophilic resin material, or a mixture thereof. For example, the wire of the coil body does not necessarily have an almost circular transverse sectional shape.
The configurations of the guide wires 1 and 1A to 1F according to the first to seventh embodiments, and the configurations of the guide wires according to the modification examples 1 to 3 may be appropriately combined. For example, the guide wire may be configured by combining the second core shaft explained in the seventh embodiment (an example with an almost polygonal transverse section) and the first core shaft explained in the second, third, and fourth embodiments. For example, the guide wire may be configured by combining the second core shaft explained in the sixth embodiment (an example without distal end portion, intermediate portion, and proximal end portion) and the first core shaft explained in the first, second, third, and fourth embodiments. For example, the guide wire may be configured by combining the first core shaft explained in the sixth embodiment (an example without distal end portion, first reduced diameter portion, first large diameter portion, second reduced diameter portion, second large diameter portion) and the second core shaft explained in the first and seventh embodiments.
In the first to seventh embodiments, although the first core shaft 10 is disposed up to the proximal end portion, a third core shaft made of SUS or the like may be disposed on the proximal end side of the first core shaft 10. In such a configuration, the nanoindentation hardness and the strain amounts leading to breaking of the distal end portions 11, 11A, and 11B of the first core shaft 10 should be compared in a range where the first core shaft 10 is disposed.
Although the aspects of the disclosed embodiments have been explained above based on the embodiments and the modification examples, the embodiments of the aforementioned aspects are made for facilitating understanding of the aspects, and do not limit the aspects. The aspects can be modified and improved without departing from the spirit of the aspects and the scope of claims, and the aspects include equivalents thereof. Further, unless the technical features are described as essential in the present specification, the technical features may be omitted as appropriate.
The present application claims priority to international application PCT/JP2019/034187, filed Aug. 30, 2019, the entire disclosure of which is incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/JP2019/034187 | Aug 2019 | US |
Child | 17678089 | US |