Patent Publication Number: US-2022218957-A1

Title: Guide wire

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to international application PCT/JP2020/035038, filed Sep. 16, 2020, and to Japanese Patent Application 2019-182149 filed Oct. 2, 2019, the entire disclosure of both of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The disclosed embodiments relate to a guide wire. 
     BACKGROUND ART 
     There is known a guide wire used for inserting a medical device such as a catheter into a blood vessel, a digestive organ, or the like. Such a guide wire needs to have flexibility and restorability with respect to bending, torquability for transmitting an operation performed on the guide wire in a hand-grip portion to a distal end side, and a strong kink resistance with respect to deformation from breakage, distortion, and crushing. For example, Patent Literature 1 discloses a feature that the torquability of a guide wire is improved by tightly winding a torque transmission coil around an outer peripheral surface of a core wire (core shaft) on a proximal end side of the core wire. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: US Patent Application Publication No. 2007/0049847 
     SUMMARY 
     Technical Problems 
     However, in the guide wire described in Patent Literature 1, there is a problem in that, when an operator grips the torque transmission coil and performs a rotating operation or a pushing operation, the torque at the hand-grip side cannot be properly transmitted to the distal end side, because the torque transmission force from the torque transmission coil to the core wire is weak. Further, in the rotating operation, the torque transmission coil may slip on the outer peripheral surface of the core wire, and thus, the torque transmission coil may be twisted, distorted, or crushed. It is noted that such a problem is not limited to an aspect in which an entire core shaft (core wire) is covered by a coil body (torque transmission coil), but is common to guide wires having an aspect in which a part of the core shaft on the proximal end side is not covered by the coil body and is exposed. 
     The disclosed embodiments have been contrived to solve at least some of the above-described problems, and one or more of the disclosed embodiments is to improve torquability in a guide wire. 
     Solutions to Problems 
     The disclosed embodiments have been contrived to solve at least some of the above-described problems, and can be implemented as the following aspects. 
     (1) According to one aspect of the disclosed embodiments, a guide wire is provided. The guide wire includes a core shaft, a coil body wound around the entire core shaft, a distal end joint portion that joins a distal end portion of the core shaft and a distal end portion of the coil body, a proximal end joint portion that joins a proximal end portion of the core shaft and a proximal end portion of the coil body, and a plurality of intermediate joint portions that are each arranged on a distal end side of a distal end of the proximal end joint portion and each join the core shaft and the coil body. 
     According to the present configuration, the guide wire includes the plurality of intermediate joint portions that are each arranged on the distal end side of the proximal end joint portion, and join the core shaft and the coil body. Therefore, for example, even when an operator grips the coil body and performs a rotating operation or a pushing operation, a torque transmission force from the coil body to the core shaft can be improved by the plurality of intermediate joint portions, thus enabling transmission of an operation performed at a hand-grip side to the distal end side. As a result, according to the guide wire of the present configuration, it is possible to improve the torquability for transmitting the operation performed on the guide wire in the hand-grip portion to the distal end side. Further, even when the rotating operation is performed, the plurality of intermediate joint portions can prevent the coil body from slipping on an outer peripheral surface of the core shaft, and thus, it is possible to prevent the coil body from being twisted, distorted, or crushed. 
     (2) In the guide wire of the above-described aspect, between the proximal end joint portion and the intermediate joint portion arranged furthermost to the distal end side among the plurality of intermediate joint portions, remaining ones of the intermediate joint portions may be arranged at equal intervals. 
     According to the present configuration, the intermediate joint portions are arranged at equal intervals, and thus, a force from the rotating operation or the pushing operation by the operator is easily transmitted to the distal end side, regardless of the position gripped by the operator. As a result, the torquability of the guide wire can be further improved. 
     (3) In the guide wire of the above-described aspect, the interval between one of the intermediate joint portions and an adjacent one of the intermediate joint portions may be 250 mm or less. 
     According to the present configuration, the interval between one of the intermediate joint portions and an adjacent one of the intermediate joint portions is 250 mm or less, and thus, the force from the rotating operation or the pushing operation by the operator is more easily transmitted to the distal end side. 
     (4) In the guide wire of the above-described aspect, at least a part of the core shaft in a circumferential direction and at least a part of the coil body in the circumferential direction may be welded in the intermediate joint portion. 
     According to the present configuration, the intermediate joint portion can be easily formed by welding at least a part of the core shaft in the circumferential direction and at least a part of the coil body in the circumferential direction. 
     (5) In the guide wire of the above-described aspect, the coil body includes a distal end side coil body arranged on the distal end side and a proximal end side coil body arranged on a proximal end side, and the intermediate joint portion arranged furthermost to the distal end side among the plurality of intermediate joint portions may join a proximal end portion of the distal end side coil body and a distal end portion of the proximal end side coil body. 
     According to the present configuration, the guide wire includes the distal end side coil body and the proximal end side coil body, and thus, configurations (shapes, materials, etc.) of the distal end side coil body and the proximal end side coil body may be changed to obtain different characteristics at the distal end side and the proximal end side of the guide wire. Further, the distal end side coil body and the proximal end side coil body are joined by the intermediate joint portion, and thus, the distal end side coil body and the proximal end side coil body can be fixed. In addition, the distal end side coil body and the proximal end side coil body are joined by the intermediate joint portion arranged furthermost to the distal end side, and thus, the remaining intermediate joint portions can be arranged in the proximal end side coil body, a torque transmission force from the proximal end side coil body to the core shaft can be improved by the remaining intermediate joint portions, and the operation performed at the hand-grip side can be transmitted to the distal end side. 
     (6) In the guide wire of the above-described aspect, the proximal end side coil body may be a multi-thread coil in which a plurality of wires are wound into multiple threads. 
     According to the present configuration, the proximal end side coil body is a multi-thread coil in which a plurality of wires are wound into multiple threads, and therefore, it is possible to further improve the torquability of the guide wire. 
     (7) In the guide wire of the above-described aspect, the proximal end side coil body may be a multi-thread coil in which a plurality of twisted wires obtained by twisting a plurality of wires are wound. 
     According to the present configuration, the proximal end side coil body is a multi-thread coil in which a plurality of twisted wires obtained by twisting a plurality of wires are wound, and therefore, it is possible to further improve the torquability of the guide wire. 
     (8) In the guide wire of the above-described aspect, the distal end side coil body may be a single-thread coil in which one wire is wound into a single thread. 
     According to the present configuration, the distal end side coil body is a single-thread coil in which one wire is wound into a single thread, and therefore, it is possible to improve the flexibility of the guide wire at the distal end side. 
     It is noted that the disclosed embodiments may be implemented in various aspects including, for example, a guide wire, a medical device including a guide wire, and a method for manufacturing the guide wire and the medical device including the guide wire. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an explanatory diagram illustrating a configuration of a guide wire according to a first embodiment. 
         FIG. 2  is an explanatory diagram illustrating a cross-sectional configuration taken along line A-A of  FIG. 1 . 
         FIG. 3  is an explanatory diagram illustrating a configuration of a guide wire according to a comparative example. 
         FIG. 4  is an explanatory diagram of a test method for a rotation followability test. 
         FIG. 5  is an explanatory graph of test results of the rotation followability test according to a comparative example. 
         FIG. 6  is an explanatory diagram of a gripping position in the rotation followability test. 
         FIG. 7  is an explanatory graph of test results of the rotation followability test. 
         FIG. 8  is an explanatory diagram illustrating a configuration of a guide wire according to a second embodiment. 
         FIG. 9  is an explanatory diagram illustrating a configuration of a guide wire according to a third embodiment. 
         FIG. 10  is an explanatory diagram illustrating a cross-sectional configuration taken along line B-B of  FIG. 9 . 
         FIG. 11  is an explanatory diagram illustrating a configuration of a guide wire according to a fourth embodiment. 
         FIG. 12  is an explanatory diagram illustrating a configuration of a guide wire according to a fifth embodiment. 
         FIG. 13  is an explanatory diagram illustrating a cross-sectional configuration taken along line C-C of  FIG. 12 . 
         FIG. 14  is an explanatory diagram illustrating a configuration of a guide wire according to a sixth embodiment. 
     
    
    
     EMBODIMENTS 
     First Embodiment 
       FIG. 1  is an explanatory diagram illustrating a configuration of a guide wire  1  according to a first embodiment. The guide wire  1  is a medical instrument used for inserting a device such as a catheter into a living body lumen, such as the vascular system, the lymphatic system, the biliary system, the urinary system, the respiratory system, the digestive system, secretory glands, and reproductive organs. The guide wire  1  includes a core shaft  10 , a distal end side coil body  20 , a proximal end side coil body  30 , an inner coil body  60 , a distal end joint portion  41 , a proximal end joint portion  42 , a first joint portion  43 , a second joint portion  71 , and a plurality of intermediate joint portions  50 . By providing the guide wire  1  with the plurality of intermediate joint portions  50 , the torquability for transmitting an operation performed on the guide wire  1  in a hand-grip portion to a distal end side may be improved. 
     In  FIG. 1 , an axis passing through a center of the guide wire  1  is represented by an axial line O (dash-dot-dash line). In the example of  FIG. 1 , the axial line O coincides with each of axes passing through centers of the core shaft  10 , the distal end side coil body  20 , the proximal end side coil body  30 , and the inner coil body  60 . However, the axial line O may be different from each central axis of each of the above-described constituent components.  FIG. 1  illustrates an X-axis, a Y-axis, and a Z-axis orthogonal to one another. The X-axis corresponds to a length direction of the guide wire  1 , the Y-axis corresponds to a height direction of the guide wire  1 , and the Z-axis corresponds to a width direction of the guide wire  1 . The left side (−X-axis direction) in  FIG. 1  is referred to as a “distal end side” of the guide wire  1  and each constituent component, and the right side in  FIG. 1  (+X-axis direction) is referred to as a “proximal end side” of the guide wire  1  and each constituent component. As for the guide wire  1  and each constituent component, an end located on the distal end side is referred to as a “distal end”, and the distal end and the vicinity thereof are referred to as a “distal end portion”. Further, an end located on the proximal end side is referred to as a “proximal end”, and the proximal end and the vicinity thereof are referred to as a “proximal end portion”. The distal end side corresponds to a “distal side” inserted into a living body, and the proximal end side corresponds to a “proximal side” operated by an operator such as a doctor. These denominations are common for the drawings from  FIG. 1  onward. 
     The 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 core shaft  10  is arranged so as to extend coaxially with the axial line O. The core shaft  10  can be formed of a material such as a stainless alloy including SUS302, SUS304, SUS316, etc., a superelastic alloy including a nickel-titanium (NiTi) alloy, etc., a piano wire, a nickel-chromium alloy, a cobalt alloy, tungsten, or the like. The core shaft  10  may be formed of a well-known material other than the above. The core shaft  10  includes a small diameter portion  11 , a reduced diameter portion  12 , and a large diameter portion  13 , in this order from the distal end side to the proximal end side. 
     The small diameter portion  11  is provided on the distal end side of the core shaft  10 . The small diameter portion  11  is a portion where an outer diameter of the core shaft  10  is smallest, and has a solid, substantially columnar shape having a constant outer diameter. The reduced diameter portion  12  is provided adjacent to the small diameter portion  11  on the proximal end side of the small diameter portion  11 . The reduced diameter portion  12  has a substantially frustoconical shape having an outer diameter that decreases, e.g., gradually decreases, from the proximal end side toward the distal end side. The large diameter portion  13  is provided adjacent to the reduced diameter portion  12  on the proximal end side of the reduced diameter portion  12 . The large diameter portion  13  has a larger diameter than the small diameter portion  11 , and has a solid, substantially cylindrical shape. The outer diameter and the length of the small diameter portion  11 , the reduced diameter portion  12 , and the large diameter portion  13  can be freely determined. The shape of the small diameter portion  11 , the reduced diameter portion  12 , and the large diameter portion  13  can also be freely determined, and may be hollow or substantially polygonal columnar. 
     The distal end side coil body  20  is arranged on the distal end side of the guide wire  1 . The distal end side coil body  20  may have a substantially hollow cylindrical shape formed by spirally winding a wire  21  around the core shaft  10 . Specifically, the distal end side coil body  20  may be a single-thread coil in which one wire  21  is wound into a single thread. In the example of  FIG. 1 , the distal end side coil body  20  covers a part of the small diameter portion  11 , the reduced diameter portion  12 , and the large diameter portion  13  on the distal end side. The wire diameter of the wire  21  of the distal end side coil body  20 , the average coil diameter of the distal end side coil body  20  (the average of the outer diameter and the inner diameter), and the length of the distal end side coil body  20  in a longitudinal direction can be freely determined. The wire  21  can be formed of, for example, a stainless alloy such as SUS304 and SUS316, a superelastic alloy such as a Ni—Ti alloy, etc., a piano wire, a radiolucent alloy such as a nickel-chromium alloy and a cobalt alloy, gold, platinum, tungsten, and a radiopaque alloy such as an alloy containing these elements (for example, a platinum-nickel alloy), or a well-known material other than the above. 
       FIG. 2  is an explanatory diagram illustrating a cross-sectional configuration taken along line A-A of  FIG. 1 . As illustrated in  FIG. 1 , the proximal end side coil body  30  is arranged on the proximal end side of the guide wire  1 . The proximal end side coil body  30  may have a substantially hollow cylindrical shape formed by spirally winding a wire  31  around the core shaft  10 . Specifically, the proximal end side coil body  30  may be a multi-thread coil in which a plurality of the wires  31  are wound into multiple threads ( FIG. 2 ). In the example of  FIG. 2 , the proximal end side coil body  30  formed by 14 of the wires  31  is illustrated, but the number of the wires  31  constituting the proximal end side coil body  30  can be freely determined. As illustrated in  FIG. 1 , the proximal end side coil body  30  covers a part of the large diameter portion  13  on the proximal end side, in other words, a remaining portion of the large diameter portion  13  that is not covered by the distal end side coil body  20 . The wire diameter of the wire  31  of the proximal end side coil body  30 , the average coil diameter of the proximal end side coil body  30 , and the length of the proximal end side coil body  30  in the longitudinal direction can be freely determined. The wire  31  can be formed of a similar material as the wire  21 . The material of the wire  31  may be the same as or different from that of the wire  21 . 
     The distal end side coil body  20  and the proximal end side coil body  30  are collectively referred to as a “coil body”. As illustrated in  FIG. 1 , in the guide wire  1  of the present embodiment, the coil body (the distal end side coil body  20  and the proximal end side coil body  30 ) is wound around the entire core shaft  10 . 
     The inner coil body  60  may have, on an inner side of the distal end side coil body  20 , a substantially hollow cylindrical shape formed by spirally winding a wire  61  around the core shaft  10 . The inner coil body  60  has a shorter length in the longitudinal direction (a direction of the axial line O) than the distal end side coil body  20 , and is arranged on the distal end side of the distal end side coil body  20 . In the example of  FIG. 1 , the inner coil body  60  covers the small diameter portion  11  and a part of the reduced diameter portion  12  on the distal end side. The wire diameter of the wire  61  of the inner coil body  60 , the average coil diameter of the inner coil body  60 , and the length of the inner coil body  60  in the longitudinal direction can be freely determined. The wire  61  can be formed of a similar material as the wire  21 . The material of the wire  61  may be the same as or different from that of the wire  21 . 
     It is noted that the inner coil body  60  may be a single-thread coil formed by winding one wire  61  into a single thread, may be a multi-thread coil formed by winding a plurality of the wires  61  into multiple threads, may be a single-thread twisted-wire coil formed by winding a twisted wire obtained by twisting a plurality of the wires  61  into a single thread, or may be a multi-thread coil (a multi-thread twisted-wire coil) formed by winding each twisted wire into multiple threads using a plurality of twisted wires obtained by twisting a plurality of the wires  61 . 
     The distal end joint portion  41  is provided on the distal end portion of the guide wire  1 , and integrally holds the core shaft  10  and the distal end side coil body  20  by joining the distal end portion of the core shaft  10  (specifically, the distal end portion of the small diameter portion  11 ) and the distal end portion of the distal end side coil body  20 . The proximal end joint portion  42  is provided on the proximal end portion of the guide wire  1 , and integrally holds the core shaft  10  and the proximal end side coil body  30  by joining the proximal end portion of the core shaft  10  (specifically, the proximal end portion of the large diameter portion  13 ) and the proximal end portion of the proximal end side coil body  30 . The distal end joint portion  41  and the proximal end joint portion  42  can be formed of any bonding agent, for example, a metal solder such as silver solder, gold solder, zinc, a Sn—Ag alloy, an Au—Sn alloy, etc., an adhesive such as an epoxy adhesive, or the like. The same bonding agent or different bonding agents may be used for the distal end joint portion  41  and the proximal end joint portion  42 . 
     The first joint portion  43  is provided on a distal end side of the plurality of intermediate joint portions  50 , and integrally holds the core shaft  10  and the distal end side coil body  20  by joining the core shaft  10  and the distal end side coil body  20 . The second joint portion  71  is provided on a proximal end side of the inner coil body  60 , and integrally holds the core shaft  10  and the inner coil body  60  by joining the core shaft  10  and the proximal end portion of the inner coil body  60 . The first joint portion  43  and the second joint portion  71  can be formed of a similar material as the distal end joint portion  41 . The material of the first joint portion  43  and the second joint portion  71  and the material of the distal end joint portion  41  may be the same or different. 
     The plurality of intermediate joint portions  50  are each arranged on a distal end side of a distal end EP of the proximal end joint portion  42 , and each join the core shaft  10  and the proximal end side coil body  30 . In the example of  FIG. 1 , the plurality of intermediate joint portions  50  include a first intermediate joint portion  51 , a second intermediate joint portion  52 , and a third intermediate joint portion  53 . 
     The first intermediate joint portion  51  is arranged furthermost to the distal end side among the plurality of intermediate joint portions  50 . The first intermediate joint portion  51  integrally holds the distal end side coil body  20 , the proximal end side coil body  30 , and the core shaft  10  by joining the proximal end portion of the distal end side coil body  20 , the distal end portion of the proximal end side coil body  30 , and the core shaft  10 . The second intermediate joint portion  52  is arranged between the first intermediate joint portion  51  and the third intermediate joint portion  53  in the longitudinal direction (the direction of the axial line O). The third intermediate joint portion  53  is arranged furthermost to the proximal end side among the plurality of intermediate joint portions  50 . The second intermediate joint portion  52  and the third intermediate joint portion  53  integrally hold the proximal end side coil body  30  and the core shaft  10  by joining the proximal end side coil body  30  and the core shaft  10 . The plurality of intermediate joint portions  50  can be formed of a similar material as the distal end joint portion  41 . The material of the plurality of intermediate joint portions  50  and the material of the distal end joint portion  41  may be the same or different. 
     As illustrated in  FIG. 1 , the remaining intermediate joint portions of the plurality of intermediate joint portions  50  (that is, the second intermediate joint portion  52  and the third intermediate joint portion  53 ) are arranged at equal intervals between the first intermediate joint portion  51  arranged furthermost to the distal end side and the proximal end joint portion  42 . In other words, a length L 1  between the proximal end of the first intermediate joint portion  51  and the distal end of the second intermediate joint portion  52 , a length L 2  between the proximal end of the second intermediate joint portion  52  and the distal end of the third intermediate joint portion  53 , and a length L 3  between the proximal end of the third intermediate joint portion  53  and the distal end EP of the proximal end joint portion  42  are all equal. Here, “equal” is not limited to the case where the lengths are completely the same, but includes an error to an extent at which a torque transmission performance described later can be achieved. 
     Hereinafter, the length L 1  between the proximal end of the first intermediate joint portion  51  and the distal end of the second intermediate joint portion  52  will also be referred to as an interval L 1  between the first intermediate joint portion  51  and the second intermediate joint portion  52 . The length L 2  between the proximal end of the second intermediate joint portion  52  and the distal end of the third intermediate joint portion  53  will also be referred to as an interval L 2  between the second intermediate joint portion  52  and the third intermediate joint portion  53 . The length L 3  between the proximal end of the third intermediate joint portion  53  and the distal end EP of the proximal end joint portion  42  will also be referred to as an interval L 3  between the third intermediate joint portion  53  and the proximal end joint portion  42 . In the guide wire  1  of the present embodiment, the interval between one intermediate joint portion and an adjacent intermediate joint portion is 250 mm or less, that is, the intervals L 1 , L 2 , and L 3 , are all 250 mm or less. To inhibit adjacent joint portions from sticking together, the lower limit of the interval between one intermediate joint portion and an adjacent intermediate joint portion is 5 mm or more. 
     Effect Example 
     As described above, the guide wire  1  according to the first embodiment includes the plurality of intermediate joint portions  50  (the first intermediate joint portion  51 , the second intermediate joint portion  52 , and the third intermediate joint portion  53 ) that are each arranged on the distal end side of the proximal end joint portion  42  and join the core shaft  10  and the proximal end side coil body  30  (the coil body). Therefore, for example, even when the operator grips the proximal end side coil body  30  and performs a rotating operation or a pushing operation, a torque transmission force from the proximal end side coil body  30  to the core shaft  10  can be improved by the plurality of intermediate joint portions  50 , thus enabling transmission of the operation performed at the hand-grip side to the distal end side. As a result, according to the guide wire  1  of the first embodiment the torquability for transmitting the operation performed on the guide wire  1  in the hand-grip portion to the distal end side may be improved. Further, even when the rotating operation is performed, the plurality of intermediate joint portions  50  can reduce or prevent the proximal end side coil body  30  from slipping on an outer peripheral surface of the core shaft  10 . Thus, damage to, e.g., twisting, distorting, or crushing, the proximal end side coil body  30  may be reduced or prevented. 
     In the guide wire  1  of the first embodiment, the remaining second and third intermediate joint portions  52  and  53  of the plurality of intermediate joint portions  50  are arranged at equal intervals between the first intermediate joint portion  51  arranged furthermost to the distal end side and the proximal end joint portion  42  ( FIG. 1 : L 1 , L 2 , and L 3 ). Therefore, the force from the rotating operation or the pushing operation by the operator is easily transmitted to the distal end side, regardless of the position gripped by the operator. As a result, the torquability of the guide wire  1  can be further improved. The interval between one intermediate joint portion and an adjacent intermediate joint portion is 250 mm or less, that is, the intervals L 1 , L 2 , and L 3  are all 250 mm or less, and therefore, the force from the rotating operation or the pushing operation by the operator is more easily transmitted to the distal end side. 
     In addition, the guide wire  1  of the first embodiment includes the distal end side coil body  20  and the proximal end side coil body  30 , and thus, the configurations (shapes, materials, etc.) of the distal end side coil body  20  and the proximal end side coil body  30  may be changed to obtain different characteristics at the distal end side and the proximal end side of the guide wire  1 . The distal end side coil body  20  and the proximal end side coil body  30  are joined by the first intermediate joint portion  51  (the intermediate joint portion), and thus, the distal end side coil body  20  and the proximal end side coil body  30  can be fixed. In addition, the distal end side coil body  20  and the proximal end side coil body  30  are joined by the first intermediate joint portion  51  arranged furthermost to the distal end side, and thus, the remaining second and third intermediate joint portions  52  and  53  can be arranged in the proximal end side coil body  30 , the torque transmission force from the proximal end side coil body  30  to the core shaft  10  can be improved by the remaining second and third intermediate joint portions  52  and  53 , and the operation performed at the hand-grip side can be transmitted to the distal end side. 
     In the first embodiment, the proximal end side coil body  30  is a multi-thread coil in which a plurality of the wires  31  are wound into multiple threads ( FIG. 2 ), and thus, it is possible to further improve the torquability of the guide wire  1 . The distal end side coil body  20  is a single-thread coil in which one wire  21  is wound into a single thread, and therefore, it is possible to improve the flexibility of the guide wire  1  at the distal end side. 
     &lt;Rotation Followability Test&gt; 
     An improvement of the rotation following performance, that is, the torque transmission performance in the guide wire  1  of the first embodiment will be described with reference to  FIGS. 3 to 7 . To prove an effect of the guide wire  1  of the first embodiment, a rotation followability test was carried out using a conventional guide wire  1 S, as a comparative example. The rotation followability test is a test for quantitatively measuring the rotation following performance of the guide wires  1  and  1 S. The following comparative example is provided in order to highlight characteristics of one or more embodiments, but it will be understood that the comparative example is not to be construed as limiting the scope of the embodiments, nor is the comparative example to be construed as being outside the scope of the embodiments. 
       FIG. 3  is an explanatory diagram illustrating a configuration of the guide wire  1 S according to the comparative example. The guide wire  1 S has the same configuration as the guide wire  1  described in  FIG. 1 , except that the guide wire  1 S does not include a plurality of intermediate joint portions  50 . The guide wire  1 S includes only the first intermediate joint portion  51  that joins the distal end side coil body  20  and the proximal end side coil body  30 , and does not include the second intermediate joint portion  52  and the third intermediate joint portion  53  described in  FIG. 1 . In other words, in the guide wire  1 S, the distal end portion of the proximal end side coil body  30  is joined to the core shaft  10  by the first intermediate joint portion  51  and the proximal end portion of the proximal end side coil body  30  is joined to the core shaft  10  by the proximal end joint portion  42 , but a portion between the distal end portion and the proximal end portion of the proximal end side coil body  30  is not joined to the core shaft  10 . 
       FIG. 4  is an explanatory diagram of a test method for the rotation followability test. In the rotation followability test, a circular ring having a radius of 50 mm was formed using a tube  81 , and a test path was created in which straight portions were formed in front of and behind the ring. The guide wire  1 S of the comparative example was inserted from one opening of the test path (an opening on the right side in  FIG. 4 ). Subsequently, the guide wire  1 S of the comparative example was pushed inward until the distal end protruded from the other opening of the tube  81 . In this state, the guide wire  1 S was rotated by gripping predetermined gripping positions (P 1  to P 5 ) on the proximal end side of the guide wire  1 S, and the number of times the distal end side of the guide wire  1 S rotated was measured. 
     The gripping positions P 1  to P 5  used in the rotation followability test will be described with reference to  FIG. 3 . The gripping position P 1  was set to a position separated from a center P 0  of the first intermediate joint portion  51  by a length L 11  in the direction of the axial line O ( FIG. 3 : an open arrow P 1 ). Similarly, the gripping position P 2  was set to a position separated from the center P 0  by a length L 12 , the gripping position P 3  was set to a position separated from the center P 0  by a length L 13 , the gripping position P 4  was set to a position separated from the center P 0  by a length L 14 , and the gripping position P 5  was set to a position separated from the center P 0  by a length L 15  ( FIG. 3 : open arrows P 2  to P 5 ). Here, the lengths L 11  to L 15  can be freely determined as long as a relationship of L 11 &gt;L 12 &gt;L 13 &gt;L 14 &gt;0.15 is satisfied. The gripping position P 1  is closest to the proximal end joint portion  42 , and the gripping position P 5  is closest to the first intermediate joint portion  51 . 
       FIG. 5  is an explanatory graph of test results of the rotation followability test according to the comparative example. In  FIG. 5 , the horizontal axis indicates a rotation angle (an input angle: degree) on the proximal end side of the guide wire  1 S of the comparative example, and the vertical axis indicates a rotation angle (an output angle: degree) on the distal end side of the guide wire  1 S of the comparative example. Firstly, a plurality of the guide wires  1 S ( FIG. 3 ) of the comparative example were prepared, and the rotation followability test was conducted in a state where the gripping position P 1  was gripped in each of the guide wires  1 S. The results indicated that a guide wire  1 Sa having a relatively excellent rotation following performance and a guide wire  1 Sb having a relatively poor rotation following performance were obtained. In  FIG. 5 , the measurement result of the guide wire  1 Sa is represented by a broken line having a narrow pitch ( 1 Sa: P 1 ), and the measurement result of the guide wire  1 Sb is represented by a thin solid line ( 18   b : P 1 ). Further, in  FIG. 5 , an ideal value SS is represented by a thick solid line. The ideal value SS represents a state where the distal end side completely follows the rotation on the proximal end side. 
     Next, the rotation followability test was conducted by gripping each of the other gripping positions P 2 , P 3 , P 4 , and P 5  described in  FIG. 3  in the guide wire  1 Sb having the relatively poor rotation following performance. In  FIG. 5 , a measurement result at the gripping position P 2  is represented by a two-dot chain line ( 1 Sb: P 2 ), a measurement result at the gripping position P 3  is represented by a dash-dot-dash line having a wide pitch ( 1 Sb: P 3 ), a measurement result at the gripping position P 4  is represented by a broken line having a wide pitch ( 1 Sb: P 4 ), and a measurement result at the gripping position P 5  is represented by a dash-dot-dash line having a narrow pitch ( 1 Sb: P 5 ). 
     In the guide wire  1 Sb, at the gripping position P 5  closest to P 0  of the first intermediate joint portion  51 , the output angle follows the input angle, so that the rotation following performance is relatively high. Further, at the gripping position P 4  located next closest to P) of the first intermediate joint portion  51  and the gripping position P 3  located second next closest, although slightly delayed, the output angle follows the input angle, so that the rotation following performance is maintained. On the other hand, at the gripping position P 2 , the output angle is delayed with respect to the input angle. This indicates that the rotation at the proximal end side is not transmitted to the distal end side in real time, and when the torque is accumulated for a while and then suddenly released, the distal end side starts rotating (a state where a so-called “rebound” occurs). Thus, the rotation following performance is relatively low at the gripping position P 2 . 
     As described above, in the guide wire  1 S of the comparative example, even when the gripping position P 1  near the proximal end joint portion  42  is gripped, unfortunately, both the guide wire  1 Sa having a relatively excellent rotation following performance and the guide wire  1 Sb having a relatively poor rotation following performance are obtained. Further, in the guide wire  1 Sb having the relatively poor rotation following performance, it can be seen that the rotation following performance may vary depending on which of the gripping positions P 2  to P 5  the operator grips, and the rotation following performance may decrease. 
     After the test of the guide wire  1 S of the comparative example, the rotation followability test was also performed on the guide wire  1  of the first embodiment by using a method similar to that of the comparative example. Specifically, first, a plurality of the guide wires  1  described in  FIG. 1  were prepared, and a rotation followability test was carried out for each by the method described in  FIG. 4  while gripping the same position as the gripping position P 1  of  FIG. 3  in each of the guide wires  1  (a position separated from the center P 0  of the first intermediate joint portion  51  by a length L 11  in the direction of the axial line O). Subsequently, for the guide wire  1   b  having the relatively poor rotation following performance, a rotation followability test was further performed for each of gripping positions P 6  and P 7  described below. 
       FIG. 6  is an explanatory diagram of the gripping positions P 6  and P 7  in the rotation followability test. The gripping position P 6  was set to a position separated by a length L 16  in the direction of the axial line O from the center P 0 ′ of the intermediate joint portion located furthermost to the proximal end side (the third intermediate joint portion  53  in the example illustrated in the drawing) among the plurality of intermediate joint portions  50  ( FIG. 6 : an open arrow P 6 ). Further, the gripping position P 7  was set to a position separated from the center P 0 ′ by a length L 17  ( FIG. 6 : an open arrow P 7 ). Here, the lengths  116  and L 17  can be freely determined as long as a relationship of L 16 &gt;L 17  is satisfied. The gripping position P 6  is closest to the proximal end joint portion  42 , and the gripping position P 7  is closest to the third intermediate joint portion  53 . 
       FIG. 7  is an explanatory graph of test results of a rotation followability test. In  FIG. 7 , the horizontal axis indicates a rotation angle (input angle: degree) on the proximal end side of the guide wire  1   b  described above (the guide wire  1   b  having the relatively poor rotation following performance among the guide wires  1  described in the first embodiment), and the vertical axis indicates a rotation angle (output angle: degree) on the distal end side of the guide wire  1   b . In  FIG. 7 , a measurement result at the gripping position P 6  of the guide wire  1   b  is represented by a two-dot chain line ( 1   b : P 6 ) and a measurement result at the gripping position P 7  of the guide wire  1   b  is represented by a dash-dot-dash line ( 1   b : P 7 ). For convenience of explanation,  FIG. 7  represents the test result of the guide wire  1 Sa having the relatively excellent rotation following performance ( 1 Sa: P 1 ), the test results of the guide wire  1 Sb having the relatively poor rotation following performance ( 1 Sb: P 1 ), and the ideal value SS described in  FIG. 5 . 
     In the guide wire  1   b , at the gripping position P 7  closest to the first intermediate joint portion  51 , the output angle follows the input angle, so that the rotation following performance is relatively high. Further, at the gripping position P 6  that is close to the proximal end joint portion  42  while being relatively far from the first intermediate joint portion  51 , the output angle gently follows the input angle, so that the rotation following performance is relatively high. 
     From the rotation followability tests described above, it can be seen that, in the guide wire  1  described in the first embodiment, as described in  FIG. 7 , a high rotation following performance (torque transmission performance) can be maintained in both of the gripping positions P 6  and P 7 , even in the example (guide wire  1   b ) in which the rotation following performance is relatively poor. This result is achieved since the interval between the gripping positions P 6  and P 7  and the nearest joint portion (the proximal end joint portion  42  in the case of the gripping position P 6  and the third intermediate joint portion  53  in the case of the gripping position P 7 ) can be designed relatively shorter than in the guide wire  1 S of the comparative example by providing the plurality of intermediate joint portions  50  in the guide wire  1 . Therefore, in the guide wire  1 , even when the above-described rotation following tests are carried out by setting the gripping positions between the first intermediate joint portion  51  and the second intermediate joint portion  52 , and between the second intermediate joint portion  52  and the third intermediate joint portion  53 , similarly good results are obtained. 
     Second Embodiment 
       FIG. 8  is an explanatory diagram illustrating a configuration of a guide wire  1 A according to a second embodiment. The guide wire  1 A of the second embodiment includes a plurality of intermediate joint portions  50 A, instead of the plurality of intermediate joint portions  50  described in the first embodiment. The plurality of intermediate joint portions  50 A include second and third intermediate joint portions  52 A and  53 A having different arrangements in the longitudinal direction (the direction of the axial line O). Specifically, the length L 11  between the proximal end of the first intermediate joint portion  51  and the distal end of the second intermediate joint portion  52 A is longer than a length L 21  between the proximal end of the second intermediate joint portion  52 A and the distal end of the third intermediate joint portion  53 A. Further, the length L 21  is longer than a length L 31  between the proximal end of the third intermediate joint portion  53 A and the distal end EP of the proximal end joint portion  42  (L 11 &gt;L 21 &gt;L 31 ). In other words, the remaining intermediate joint portions (the second intermediate joint portion  52 A and the third intermediate joint portion  53 A) are arranged at equal intervals between the first intermediate joint portion  51  arranged furthermost to the distal end side and the proximal end joint portion  42 . 
     As described above, various modifications may be applied to the configuration of the plurality of intermediate joint portions  50 A, and at least some of the intermediate joint portions of the plurality of intermediate joint portions  50 A may not be arranged at equal intervals. In this case, the size relationship of the lengths L 11 , L 21 , and L 31  described above can be freely changed. The guide wire  1 A according to the second embodiment can also exhibit an effect similar to that of the first embodiment. Further, in the guide wire  1 A of the second embodiment, the plurality of intermediate joint portions  50 A can be easily manufactured, and the manufacturing cost of the guide wire  1 A can be reduced. 
     Third Embodiment 
       FIG. 9  is an explanatory diagram illustrating a configuration of a guide wire  1 B according to a third embodiment. The guide wire  1 B of the third embodiment includes a plurality of intermediate joint portions  50 B instead of the plurality of intermediate joint portions  50  described in the first embodiment. The plurality of intermediate joint portions  50 B include a second intermediate joint portion  52 B instead of the second intermediate joint portion  52 , and a third intermediate joint portion  53 B instead of the third intermediate joint portion  53 . 
       FIG. 10  is an explanatory diagram illustrating a cross-sectional configuration taken along line B-B of  FIG. 9 . As illustrated in  FIG. 10 , the second intermediate joint portion  52 B is formed by welding a part of the large diameter portion  13  of the core shaft  10  in a circumferential direction and a part of the proximal end side coil body  30  in the circumferential direction. A range in which the core shaft  10  and the proximal end side coil body  30  are welded can be freely determined, and as illustrated in the drawing, the range may be about 30 degrees in the circumferential direction, or about 180 degrees, or about 360 degrees (that is, an aspect in which the core shaft  10  and the proximal end side coil body  30  are welded along the entire circumferential direction). Further, a welding length in a long axis direction (the direction of the axial line O) can also be freely determined. 
     Thus, various modifications may be applied to the configuration of the plurality of intermediate joint portions  50 B, and at least some of the plurality of intermediate joint portions  50 B may be formed by a means other than joining by a joining agent. As the means other than joining, a well-known means such as crimping can be utilized in addition to the above-described welding. Further, all of the plurality of intermediate joint portions  50 B may be formed by a means other than joining, or at least some of the plurality of intermediate joint portions  50 B may be formed by a means other than joining. The guide wire  1 B according to the third embodiment can also exhibit an effect similar to that of the first embodiment. Further, in the guide wire  1 B of the third embodiment, the plurality of intermediate joint portions  50 B can be easily formed, and the manufacturing cost of the guide wire  1 B can be reduced. 
     Fourth Embodiment 
       FIG. 11  is an explanatory diagram illustrating a configuration of a guide wire  1 C according to a fourth embodiment. The guide wire  1 C of the fourth embodiment does not include the proximal end side coil body  30  described in the first embodiment, includes a distal end side coil body  20 C instead of the distal end side coil body  20 , includes a plurality of intermediate joint portions  50 C instead of the plurality of intermediate joint portions  50 , and includes a proximal end joint portion  42 C instead of the proximal end joint portion  42 . The length of the distal end side coil body  20 C in the long axis direction (the direction of the axial line O) is different from that of the first embodiment. Specifically, the distal end side coil body  20 C covers the entire guide wire  1  in the long axis direction. The plurality of intermediate joint portions  50 C include first to third intermediate joint portions  510  to  53 C. The first to third intermediate joint portions  51 C to  53 C respectively join the core shaft  10  and the distal end side coil body  20 C. The proximal end joint portion  42 C joins the proximal end portion of the core shaft  10  and the proximal end portion of the distal end side coil body  20 C. 
     Thus, various modifications may be applied to the configuration of the guide wire  1 C, and the coil body arranged on the outside may be configured from one type of coil. The coil body arranged on the outside may be a single-thread coil illustrated in  FIG. 11 , or may be a multi-thread coil in which a plurality of wires are wound into multiple threads. Further, the coil body arranged on the outside may be a single-thread twisted-wire coil formed by winding a twisted wire obtained by twisting a plurality of wires into a single thread, or may be a multi-thread twisted-wire coil formed by winding each twisted wire into multiple threads using a plurality of twisted wires obtained by twisting a plurality of wires. The guide wire  1 C according to the fourth embodiment can also exhibit an effect similar to that of the first embodiment. Further, in the guide wire  1 C of the fourth embodiment, the guide wire  1 C can be easily formed, and the manufacturing cost of the guide wire  1 C can be reduced. 
     Fifth Embodiment 
       FIG. 12  is an explanatory diagram illustrating a configuration of a guide wire  1 D according to a fifth embodiment.  FIG. 13  is an explanatory diagram illustrating a cross-sectional configuration taken along line C-C of  FIG. 12 . The guide wire  1 D of the fifth embodiment includes a proximal end side coil body  30 D instead of the proximal end side coil body  30  described in the first embodiment. As illustrated in  FIG. 13 , the proximal end side coil body  30 D is a multi-thread coil (multi-thread twisted-wire coil) in which a plurality of twisted wires  31 D obtained by twisting a plurality of wires are wound. In the example of  FIG. 13 , the number of twisted wires  31 D constituting the proximal end side coil body  30 D is 14, and the number of wires constituting each of the twisted wires  31 D is 7, but the number of twisted wires  31 D and the number of wires constituting the twisted wires  31 D can be freely determined. Further, the wires constituting the twisted wires  31 D can be formed of a similar material as the wire  21 . The material of the wires constituting the twisted wires  311 ) and the material of the wire  21  may be the same or different. 
     Thus, various modifications may be applied to the configuration of the proximal end side coil body  30 D, and the proximal end side coil body  30 D may be a multi-thread coil in which a plurality of the twisted wires  31 D obtained by twisting a plurality of wires are wound. In the plurality of twisted wires  31 D, the number of wires constituting some of the twisted wires  31 D and the number of wires constituting the other ones of the twisted wires  31 D may be different from each other. For example, some of the twisted wires  31 D may be constituted by seven wires, and the other ones of the twisted wires  31 D may be constituted by five wires. The guide wire  1 D according to the fifth embodiment can also exhibit an effect similar to that of the first embodiment. Further, in the guide wire  1 D of the fifth embodiment, the proximal end side coil body  30 D is a multi-thread coil (multi-thread twisted-wire coil) in which the plurality of twisted wires  31 D obtained by twisting a plurality of wires are wound. Thus, the torquability of the guide wire  1 D can be further improved. 
     Sixth Embodiment 
       FIG. 14  is an explanatory diagram illustrating a configuration of a guide wire  1 E according to a sixth embodiment. The guide wire  1 E of the sixth embodiment does not include the inner coil body  60  described in the first embodiment. Thus, various modifications may be applied to the configuration of the guide wire  1 E, and the guide wire  1 E may not include at least a part of the configuration described in the first embodiment, and may include other configurations not described in the first embodiment. For example, the guide wire  1 E may not include the first joint portion  43 . The guide wire  1 E according to the sixth embodiment can also exhibit an effect similar to that of the first embodiment. 
     Modifications of Embodiment 
     The disclosed embodiments are not limited to the above-described embodiments, and may be implemented in various modes without departing from the spirit of the disclosed embodiments. The following modifications can be applied, for example. 
     First Modification 
     In the above-described first to sixth embodiments, examples of the configurations of the guide wires  1  and  1 A to  1 E are described. However, the configuration of the guide wire  1  can be variously modified. For example, the guide wire  1  may further include a second core shaft (also referred to as a shaping ribbon) different from the core shaft  10 . In this case, the proximal end portion of the second core shaft may be joined to the core shaft  10 , and the distal end portion of the second core shaft may be fixed to the distal end side coil body  20  and the inner coil body  60  by the distal end joint portion  41 . In a configuration in which the second core shaft is provided, it is possible to improve the shaping performance on the distal end side of the guide wire  1 . For example, the guide wire may be designed as a product in which the distal end side is curved in advance. 
     For example, various modifications may be applied to the configuration of the core shaft  10 , and the core shaft  10  may not include the small diameter portion  11 , the reduced diameter portion  12 , and the large diameter portion  13 , may have a configuration in which the outer diameter of the entire longitudinal direction (the direction of the axial line O) is substantially the same, or may have a configuration in which the diameter of the entire longitudinal direction is reduced from the proximal end side to the distal end side. For example, the core shaft  10  may include a second reduced diameter portion in which the diameter is reduced from the proximal end side to the distal end side on the proximal end side of the large diameter portion  13 , or may further include a second large diameter portion having a larger diameter than the large diameter portion  13  on the proximal end side of the second reduced diameter portion. 
     Second Modification 
     In the first to sixth embodiments, an example of each configuration of the two coil bodies arranged on an outer side of the guide wires  1  and  1 A to  1 E (specifically, the distal end side coil bodies  20  and  20 C, and the proximal end side coil bodies  30  and  30 D) is described. However, various modifications may be applied to the configuration of the coil body. For example, the coil body may not cover the core shaft  10  in the entire longitudinal direction, and a part of the core shaft  10  on the proximal end side may not be covered by the coil body ( FIG. 1 : the proximal end side coil body  30 ) and may be exposed to the outside. 
     For example, the coil body arranged on an outer side of the guide wires  1  and  1 A to  1 E may be composed of one coil body or may be composed of three or more coil bodies. The coil body may be a single-thread coil formed by winding one wire into a single thread, or may be a multi-thread coil formed by winding a plurality of wires into multiple threads, or may be a single-thread twisted-wire coil formed by winding a twisted wire obtained by twisting a plurality of wires into a single thread, or may be a multi-thread twisted-wire coil (multi-thread coil) formed by winding each twisted wire into multiple threads using a plurality of twisted wires obtained by twisting a plurality of wires. 
     For example, the two coil bodies arranged on an outer side of the guide wires  1  and  1 A to  1 E (specifically, at least one of the distal end side coil bodies  20  and  20 C, and at least one of the proximal end side coil bodies  30  and  30 D) may have a dense winding configuration having no gap between adjacent wires, a sparse winding configuration having a gap between adjacent wires, or a combined configuration of the dense winding configuration and the sparse winding configuration. The coil body may include, for example, a resin layer coated with a hydrophobic resin material, a hydrophilic resin material, or a mixture thereof. For example, the transverse sectional shape of the wire of the coil body does not need to be substantially circular. 
     Third Modification 
     In the first to sixth embodiments described above, examples of the configuration of the plurality of intermediate joint portions  50  and  50 A to  50 C are described. However, various modifications may be applied to the configuration of the plurality of intermediate joint portions  50 . For example, the number of intermediate joint portions provided in the guide wires  1  and  1 A to  1 E is not limited to 3 as described above, and may be any number of 2 or more. For example, the shape of the intermediate joint portions can also be freely determined. For example, the interval between one intermediate joint portion and an adjacent intermediate joint portion may be 250 mm or more, and can be any value. For example, the interval between the one intermediate joint portion and the adjacent intermediate joint portion may not be based on an end face (the distal end/the proximal end) of the intermediate joint portion, but may be measured according to the position of an approximate central part of the intermediate joint portion in the longitudinal direction (the direction of the axial line O). 
     For example, the first intermediate joint portions  51  and  51 C arranged furthermost to the distal end side among the plurality of intermediate joint portions  50  and  50 A to  50 C, may not join the proximal end portion of the distal end side coil body  20  and the distal end portion of the proximal end side coil body  30 . In this case, the first intermediate joint portion  51  may be arranged on the distal end side of a boundary between the distal end side coil body  20  and the proximal end side coil body  30  (that is, the distal end side coil body  20 ), or may be arranged on the proximal end side of the boundary (that is, the proximal end side coil body  30 ). 
     Fourth Modification 
     The configurations of the guide wires  1  and  1 A to  1 E of the first to sixth embodiments and the configurations of the guide wires  1  and  1 A to  1 E of the first to third modifications described above may be appropriately combined. For example, the guide wire  1 C that does not include the proximal end side coil body  30  described in the fourth embodiment may be configured to include the plurality of intermediate joint portions  50  described in the second or third embodiment. For example, the guide wire  1 D that includes the proximal end side coil body  30 D described in the fifth embodiment may be configured to include the plurality of intermediate joint portions  50  described in the second or third embodiment. For example, the guide wire  1 E that does not include the inner coil body  60  described in the sixth embodiment may be configured to include the plurality of intermediate joint portions  50  described in the second or third embodiment. 
     Although the aspects have been described based on the embodiments and the modifications, the embodiments of the above-described aspects are for facilitating understanding of the aspects, and do not limit the aspects. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. The aspects can be modified and improved without departing from the spirit of the aspects and the scope of the claims, and equivalent aspects are included in the aspects. Further, unless a technical feature is described as essential in the present specification, the technical feature may be omitted as appropriate. 
     DESCRIPTION OF REFERENCE NUMERALS 
     
         
         
           
               1 ,  1 A to  1 E,  1   b  . . . Guide wire 
               1 S,  1 Sa,  1 Sb . . . Guide wire of comparative example 
               10  . . . Core shaft 
               11  . . . Small diameter portion 
               12  . . . Reduced diameter portion 
               13  . . . Large diameter portion 
               20 ,  20 C . . . Distal end side coil body 
               21  . . . Wire 
               30 ,  30 D . . . Proximal end side coil body 
               31  . . . Wire 
               31 D . . . Twisted wire 
               41  . . . Distal end joint portion 
               42 ,  42 C . . . Proximal end joint portion 
               43  . . . First joint portion 
               50 ,  50 A to  50 C . . . Intermediate joint portion 
               51 ,  51 C . . . First intermediate joint portion 
               52 ,  52 A to  52 C . . . Second intermediate joint portion 
               53 ,  53 A to  53 C . . . Third intermediate joint portion 
               60  . . . Inner coil body 
               61  . . . Wire 
               71  . . . Second joint portion 
               81  . . . Tube