Guide wire

Abstract

To increase rigidity of a guide wire while achieving the identification of the position and shape of the guide wire utilizing an optical fiber.SOLUTION: A guide wire comprises a core shaft, a first cylindrical body, and an optical fiber. The first cylindrical body is a cylindrical member that is arranged on the side of a base end with respect to the core shaft and that has a first lumen. The optical fiber is extended toward the tip side of the core shaft along an outer peripheral surface of the core shaft through the first lumen.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The technology disclosed in this specification relates to a guide wire.

Background Art

[0002] As a technology for specifying the position and shape of a long medical device inserted into a living body lumen such as a blood vessel, a technology called FORS (Fiber Optic Real Shape) is known. A long medical device using FORS includes a cylindrical body and an optical fiber disposed in the hollow portion of the cylindrical body, and measures the distortion of the optical fiber by analyzing the reflected light of the laser light transmitted through the optical fiber. Thereby, the position and shape of the optical fiber, and thus the long medical device, are specified and imaged in real time (see, for example, Patent Document 1). By using a long medical device using FORS, the amount of X-ray exposure and the amount of contrast agent projection can be reduced, and for example, the invasiveness of PCI (percutaneous coronary intervention) treatment can be reduced.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described conventional long medical device, a cylindrical body is used as a member for supporting the optical fiber. Since the ratio of the wall thickness to the outer diameter of the cylindrical body is small and the processing difficulty is high, it is difficult to increase the rigidity. Therefore, in the conventional long medical device, the rigidity of the cylindrical body, and thus the rigidity of the long medical device, is low. As a result, for example, the supportability of a medical device such as a catheter (hereinafter referred to as a "combined device") and the bending durability of the tip portion are low.

[0005] This specification discloses a technology capable of solving the above-mentioned problems. [Means for solving the problem]

[0006] The technologies disclosed herein can be implemented, for example, in the following forms:

[0007] (1) The guidewire disclosed herein comprises a core shaft, a first cylindrical body, and an optical fiber. The first cylindrical body is a cylindrical member located on the proximal end side of the core shaft and having a first lumen. The optical fiber passes through the first lumen and extends along the outer circumferential surface of the core shaft toward the tip side of the core shaft.

[0008] This guidewire enables the identification (imaging) of the position and shape of the guidewire using an optical fiber. Furthermore, in this guidewire, the optical fiber is supported by a core shaft rather than a hollow cylindrical body. Since the core shaft does not have a hollow section, it can be made more rigid than a hollow cylindrical body if the outer diameter is the same. Therefore, with this guidewire, the rigidity of the guidewire can be increased by the presence of the core shaft, and as a result, the support for concomitant devices such as catheters and the bending durability of the guidewire tip can be improved. Thus, this guidewire enables the identification (imaging) of the position and shape of the guidewire using an optical fiber, while the rigidity of the guidewire can be increased by the presence of the core shaft, improving the support for concomitant devices and the bending durability of the tip.

[0009] (2) In the guide wire described above, the core shaft may be configured to have a tapered shaft portion that constitutes the base end of the core shaft and whose outer diameter gradually decreases toward the base end. With this guide wire, compared to a configuration in which the core shaft does not have a tapered shaft portion, the number of places in which the optical fiber bends at a large angle of about 90 degrees in the path from the outer circumferential surface of the base end of the core shaft to the first lumen of the first cylindrical body can be reduced. Therefore, with this guide wire, the risk of optical fiber breakage can be reduced.

[0010] (3) In the above guide wire, a groove extending from the base end to the tip end of the core shaft is formed on the outer circumferential surface of the core shaft, and at least a portion of the optical fiber along the direction of extension may be housed in the groove. This guide wire makes it possible to improve the stability of the position of the optical fiber on the outer circumferential surface of the core shaft, thereby improving the ability of the optical fiber to follow the deformation of the core shaft, and improving the accuracy of identifying (imaging) the position and shape of the guide wire using the optical fiber.

[0011] (4) In the above guide wire, the groove at the base end of the core shaft may have a tapered groove portion whose depth gradually increases toward the base end. Compared to a configuration in which the groove does not have a tapered groove portion and the groove depth is constant to the base end of the groove, this guide wire can reduce the number of places in which the optical fiber bends at a large angle of about 90 degrees, thereby reducing the risk of optical fiber breakage.

[0012] (5) In the guide wire described above, the core shaft has a large diameter portion and a small diameter portion located towards the tip of the large diameter portion and having a smaller outer diameter than the large diameter portion. The guide wire may further include a second cylindrical body that covers at least the small diameter portion of the core shaft and the tip of the optical fiber, the inner diameter of the portion covering the small diameter portion being smaller than the sum of the outer diameter of the large diameter portion of the core shaft and the outer diameter of the optical fiber. With this guide wire, the optical fiber extending towards the tip along the outer circumferential surface of the large diameter portion of the core shaft is pressed towards the core shaft by the inner circumferential surface of the second cylindrical body at a position facing the small diameter portion of the core shaft. Therefore, with this guide wire, the presence of the second cylindrical body can improve the tracking ability of the optical fiber when the core shaft deforms, and can improve the accuracy of identifying (imaging) the position and shape of the guide wire using the optical fiber.

[0013] (6) In the guide wire described above, at least a portion of the position along the extension direction of the second cylindrical body, the inner diameter of the second cylindrical body may be configured to match the sum of the outer diameter of the core shaft and the outer diameter of the optical fiber. With this guide wire, the presence of the second cylindrical body makes it possible to maintain contact between the optical fiber and the core shaft, effectively improving the ability of the optical fiber to follow the deformation of the core shaft, and effectively improving the accuracy of identifying (imaging) the position and shape of the guide wire using the optical fiber.

[0014] Furthermore, the technologies disclosed herein can be implemented in various forms, for example, as guide wires, medical systems equipped with guide wires, and methods for manufacturing them. [Brief explanation of the drawing]

[0015] [Figure 1] This is an explanatory diagram illustrating the configuration of the guide wire 100 in the first embodiment. [Figure 2] This is an explanatory diagram illustrating the configuration of the guide wire 100 in the first embodiment. [Figure 3] This is an explanatory diagram illustrating the configuration of the guide wire 100 in the first embodiment. [Figure 4] This is an explanatory diagram illustrating the configuration of the guide wire 100 in the first embodiment. [Figure 5] This is an explanatory diagram illustrating the configuration of the guide wire 100 in the first embodiment. [Figure 6] This is an explanatory diagram illustrating the configuration of the guide wire 100a in the second embodiment. [Figure 7] This is an explanatory diagram illustrating the configuration of the guide wire 100b in the third embodiment. [Figure 8] This is an explanatory diagram illustrating the configuration of the guide wire 100b in the third embodiment. [Figure 9] This is an explanatory diagram illustrating the configuration of the guide wire 100b in the third embodiment. [Modes for carrying out the invention]

[0016] A. First Embodiment: A-1. Configuration of guide wire 100: Figures 1 to 5 are explanatory diagrams schematically showing the configuration of the guide wire 100 in the first embodiment. In FIG. 1, the configuration of the longitudinal section (YZ section) of the guide wire 100 is shown. In FIG. 2, the configuration of the cross section (XY section) of the guide wire 100 at the position II-II in FIG. 1 is shown. In FIG. 3, the configuration of the cross section of the guide wire 100 at the position III-III in FIG. 1 is shown. In FIG. 4, the configuration of the cross section of the guide wire 100 at the position IV-IV in FIG. 1 is shown. In FIG. 5, the configuration of the cross section of the guide wire 100 at the position V-V in FIG. 1 is shown. Note that in FIG. 1, a part of the guide wire 100 is not shown. In FIG. 1, the positive Z-axis direction side is the distal side (tip side) inserted into the body, and the negative Z-axis direction side is the proximal side (base end side) operated by a technician such as a doctor. In FIG. 1, the guide wire 100 is shown in a straight line state substantially parallel to the Z-axis direction as a whole, but at least a part of the configuration of the guide wire 100 has flexibility enough to be curved. In this specification, for the guide wire 100 and its respective component members, the end on the tip side is referred to as the "tip", the tip and its vicinity are referred to as the "tip portion", the end on the base end side is referred to as the "base end", and the base end and its vicinity are referred to as the "base end portion".

[0017] The guide wire 100 is a long medical device inserted into a body lumen. The total length of the guide wire 100 is, for example, about 1500 mm to 3200 mm. The guide wire 100 of the present embodiment has a FORS function of specifying and imaging the position and shape of the guide wire 100 in real time without performing X-ray irradiation by using the optical fiber 70. The guide wire 100 is used alone or in combination with other imaging methods (for example, CT or MRI) to specify the position and shape of the guide wire 100 itself or the body lumen into which the guide wire 100 is inserted. Further, the guide wire 100 may be used to guide a combined device such as a catheter.

[0018] The guide wire 100 includes a core shaft 10, a proximal side cylindrical body 60, an outer cylindrical body 20, an inner cylindrical body 40, and an optical fiber 70.

[0019] The core shaft 10 is a long rod-shaped member extending along the central axis of the guide wire 100. The shape of the cross-section at each position of the core shaft 10 can be any shape, for example, substantially circular.

[0020] As shown in FIGS. 1 to 4, the core shaft 10 has a small-diameter portion 11, a first tapered portion 12, a large-diameter portion 13, and a second tapered portion 14. The small-diameter portion 11 constitutes the tip of the core shaft 10 and is a portion having a substantially constant outer diameter. The first tapered portion 12 is adjacent to the proximal side of the small-diameter portion 11 and is a tapered (frustum-shaped) portion whose outer diameter gradually increases from the tip side to the proximal side. The outer diameter of the first tapered portion 12 substantially coincides with the outer diameter of the small-diameter portion 11 at the boundary position with the small-diameter portion 11 and substantially coincides with the outer diameter of the large-diameter portion 13 at the boundary position with the large-diameter portion 13. The large-diameter portion 13 is adjacent to the proximal side of the first tapered portion 12 and is a portion having a substantially constant outer diameter larger than the outer diameter of the small-diameter portion 11. The second tapered portion 14 is adjacent to the proximal side of the large-diameter portion 13 and constitutes the proximal end of the core shaft 10, and is a tapered (frustum-shaped) portion whose outer diameter gradually decreases from the tip side to the proximal side. The outer diameter of the second tapered portion 14 substantially coincides with the outer diameter of the large-diameter portion 13 at the boundary position with the large-diameter portion 13. The second tapered portion 14 is an example of a tapered shaft portion.

[0021] As shown in FIGS. 1 and 5, the proximal-side cylindrical body 60 is disposed on the proximal side of the core shaft 10 and is a cylindrical member having a lumen 62 for an optical fiber. The proximal-side cylindrical body 60 is composed of a tubular body having a uniform cross-section. The shape of the cross-section of the proximal-side cylindrical body 60 can be any shape, for example, substantially annular. The lumen 62 for an optical fiber is formed, for example, at a position coaxial with the central axis of the guide wire 100. The proximal-side cylindrical body 60 is an example of a first cylindrical body, and the lumen 62 for an optical fiber is an example of a first lumen.

[0022] The optical fiber 70 is a linear member that transmits optical signals to realize the FORS described above. As shown in Figures 1 to 5, the optical fiber 70 passes through the optical fiber lumen 62 of the proximal end cylindrical body 60 and extends along the outer circumferential surface of the core shaft 10 toward the tip side of the core shaft 10. More specifically, the optical fiber 70 extends from the proximal end side toward the tip side while bending along the outer circumferential surface of the core shaft 10 over substantially the entire length of the core shaft 10 (over the second tapered portion 14, the large diameter portion 13, the first tapered portion 12, and the small diameter portion 11). The positions of the optical fiber 70 along the circumferential direction of the core shaft 10 are the same at each position along the extension direction of the core shaft 10. That is, when the core shaft 10 is viewed from a predetermined direction (the Y-axis direction in the example of Figure 1), the optical fiber 70 extends in a substantially straight line.

[0023] The optical fiber 70 is joined to the core shaft 10, for example, by adhesive, to its tip (small diameter portion 11) and base (second tapered portion 14). The portion of the optical fiber 70 closer to the base end than the base end cylindrical body 60 is connected to a control device (not shown) that controls the transmission and reception of laser light through the optical fiber 70, the measurement of distortion of the optical fiber 70 based on reflected light, and imaging based on the distortion.

[0024] As shown in Figures 1 to 4, the outer cylindrical body 20 is a cylindrical member positioned on the outer circumference of the core shaft 10 and optical fiber 70 so as to cover the core shaft 10 and optical fiber 70. The outer cylindrical body 20 has a tip outer cylindrical body 21 and a base outer cylindrical body 22. The outer cylindrical body 20 is an example of a third cylindrical body.

[0025] The outer cylindrical tip 21 constitutes the tip portion of the outer cylindrical tip 20 and covers the narrow-diameter portion 11, the first tapered portion 12, and a part of the tip side of the wide-diameter portion 13 of the core shaft 10. The outer cylindrical tip 21 is composed of a coil body formed by spirally winding a wire. The outer cylindrical tip 21 may be a single coil or a stranded coil. Furthermore, the outer cylindrical tip 21 may be a loosely wound coil or a tightly wound coil.

[0026] The base outer cylindrical body 22 is adjacent to the base end side of the tip outer cylindrical body 21 and constitutes the base end of the outer cylindrical body 20, covering a part of the base end side of the large diameter portion 13 of the core shaft 10 and the second tapered portion 14. The base outer cylindrical body 22 is made of a tubular body having a uniform cross-section. At its tip, the base outer cylindrical body 22 is joined to the base end of the tip outer cylindrical body 21, for example by welding. Furthermore, at its base end, the base outer cylindrical body 22 is joined to the tip of the base cylindrical body 60, for example by welding.

[0027] As shown in Figure 3, the inner diameter ID20 of the base outer cylindrical body 22 of the outer cylindrical body 20 is approximately equal to the sum of the outer diameter OD10 of the large diameter portion 13 of the core shaft 10 and the outer diameter OD70 of the optical fiber 70. Therefore, the space 26 formed between the inner circumferential surface of the base outer cylindrical body 22 of the outer cylindrical body 20 and the outer circumferential surface of the large diameter portion 13 of the core shaft 10 is minimized.

[0028] As shown in Figure 1, the tip of the outer cylindrical body 20 (tip outer cylindrical body 21) is joined to the tip of the core shaft 10 by the tip joint 50. The outer cylindrical body 20 and the core shaft 10 may be joined to each other at other locations (for example, near the joint between the tip outer cylindrical body 21 and the base outer cylindrical body 22). The optical fiber 70 may also be joined at the joint between the outer cylindrical body 20 and the core shaft 10.

[0029] As shown in Figures 1 and 2, the inner cylindrical body 40 is a cylindrical member positioned on the outer circumference of the core shaft 10 and the optical fiber 70 so as to cover the tip of the core shaft 10 and the tip of the optical fiber 70. More specifically, the inner cylindrical body 40 covers the narrow diameter portion 11, the first tapered portion 12, and a part of the tip side of the wide diameter portion 13 of the core shaft 10. The tip of the inner cylindrical body 40 is joined to the tip of the core shaft 10 and the tip of the outer cylindrical body 20 by a tip joint portion 50. The inner cylindrical body 40 is composed of a coil body formed by spirally winding a wire. The inner cylindrical body 40 may be a single coil or a stranded coil. Furthermore, the inner cylindrical body 40 may be a loosely wound coil or a tightly wound coil. The inner cylindrical body 40 is an example of a second cylindrical body.

[0030] The inner cylindrical body 40 has a narrow diameter portion 41, a tapered portion 42, and a wide diameter portion 43. The narrow diameter portion 41 of the inner cylindrical body 40 constitutes the tip of the inner cylindrical body 40, has a substantially constant inner and outer diameter, and is the portion that covers the narrow diameter portion 11 of the core shaft 10. The tapered portion 42 of the inner cylindrical body 40 is adjacent to the base end side of the narrow diameter portion 41, has a tapered shape (hollow frustoconical shape) where the inner and outer diameters gradually increase from the tip side to the base end side, and is the portion that covers the first tapered portion 12 of the core shaft 10. The wide diameter portion 43 of the inner cylindrical body 40 is adjacent to the base end side of the tapered portion 42, has a substantially constant inner and outer diameter that is larger than the inner and outer diameters of the narrow diameter portion 41, and is the portion that covers the wide diameter portion 13 of the core shaft 10.

[0031] As shown in Figures 1 and 2, at each position along the extension direction of the inner cylindrical body 40, the inner diameter ID40 of the inner cylindrical body 40 is approximately equal to the sum of the outer diameter OD10 of the core shaft 10 and the outer diameter OD70 of the optical fiber 70. Therefore, the inner circumferential surface of the inner cylindrical body 40 is in contact with the optical fiber 70, and as a result, the inner cylindrical body 40 restricts the optical fiber 70 from separating from the outer circumferential surface of the core shaft 10. Furthermore, as a result of the above relationship between the inner and outer diameters, the inner diameter ID40 in the narrow-diameter portion 41 and the tapered portion 42 of the inner cylindrical body 40 is smaller than the sum of the outer diameter OD10 of the wide-diameter portion 13 of the core shaft 10 and the outer diameter OD70 of the optical fiber 70.

[0032] Furthermore, as shown in Figures 1 and 2, the outer diameter OD40 of the inner cylindrical body 40 is less than or equal to the inner diameter ID20 of the outer cylindrical body 20 (tip outer cylindrical body 21). More specifically, at the location of the large diameter portion 43 of the inner cylindrical body 40, the outer diameter OD40 of the inner cylindrical body 40 is approximately equal to the inner diameter ID20 of the outer cylindrical body 20, and at the locations of the tapered portion 42 and the small diameter portion 41 of the inner cylindrical body 40, the outer diameter OD40 of the inner cylindrical body 40 is smaller than the inner diameter ID20 of the outer cylindrical body 20. Therefore, at the locations of the tapered portion 42 and the small diameter portion 41 of the inner cylindrical body 40, a space 24 exists between the inner circumferential surface of the outer cylindrical body 20 and the outer circumferential surface of the inner cylindrical body 40.

[0033] The core shaft 10, the base end cylindrical body 60, the outer cylindrical body 20, and the inner cylindrical body 40 are formed of metal, for example, stainless steel (SUS302, SUS304, SUS316, etc.), Ni-Ti alloy, piano wire, etc. At least a portion of these members may be made of radiopaque material (for example, platinum or tungsten, etc.). The tip joint 50 is formed of metal solder (Au-Sn alloy, Sn-Ag alloy, Sn-Pb alloy, Pb-Ag alloy, etc.), brazing material (aluminum alloy brazing, silver brazing, gold brazing, etc.), adhesive (epoxy adhesive, etc.), etc.

[0034] Furthermore, at least a portion of the guidewire 100 may be covered with a hydrophilic resin coating layer.

[0035] A-2. Effects of this embodiment: As described above, the guide wire 100 of this embodiment comprises a core shaft 10, a base-end cylindrical body 60, and an optical fiber 70. The base-end cylindrical body 60 is positioned on the base side of the core shaft 10 and is a cylindrical body having an optical fiber lumen 62. The optical fiber 70 passes through the optical fiber lumen 62 and extends along the outer circumferential surface of the core shaft 10 toward the tip side of the core shaft 10. Therefore, with the guide wire 100 of this embodiment, it is possible to identify (image) the position and shape of the guide wire 100 using the optical fiber 70.

[0036] Furthermore, in the guide wire 100 of this embodiment, the optical fiber 70 is supported by a core shaft 10 rather than a hollow cylindrical body. Since the core shaft 10 does not have a hollow portion, it can be made more rigid than a hollow cylindrical body if the outer diameter is the same. Therefore, according to the guide wire 100 of this embodiment, the rigidity of the guide wire 100 can be increased by the presence of the core shaft 10, and as a result, the support for concomitant devices such as catheters and the bending durability of the tip of the guide wire 100 can be improved.

[0037] Thus, according to the guide wire 100 of this embodiment, while the position and shape of the guide wire 100 can be identified (imaged) using the optical fiber 70, the rigidity of the guide wire 100 can be increased by the presence of the core shaft 10, thereby improving the supportability of the accompanying device and the bending durability of the tip.

[0038] Furthermore, in the guide wire 100 of this embodiment, the core shaft 10 has a second tapered portion 14. The second tapered portion 14 constitutes the base end of the core shaft 10 and is a tapered portion in which the outer diameter gradually decreases toward the base end. Therefore, compared to a configuration in which the core shaft 10 does not have a second tapered portion 14 and the large diameter portion 13 extends to the base end of the core shaft 10, the number of places in which the optical fiber 70 bends at a large angle of about 90 degrees in the path from the outer circumferential surface of the base end of the core shaft 10 to the optical fiber lumen 62 of the cylindrical body 60 on the base end side can be reduced. Accordingly, the guide wire 100 of this embodiment can reduce the risk of breakage of the optical fiber 70.

[0039] Furthermore, in the guide wire 100 of this embodiment, the core shaft 10 has a large diameter portion 13 and a small diameter portion 11 located towards the tip of the large diameter portion 13 and having a smaller outer diameter than the large diameter portion 13. The guide wire 100 also includes an inner cylindrical body 40. The inner cylindrical body 40 covers at least the small diameter portion 11 of the core shaft 10 and the tip of the optical fiber 70. The inner diameter of the portion of the inner cylindrical body 40 that covers the small diameter portion 11 of the core shaft 10 (the small diameter portion 41 of the inner cylindrical body 40) is smaller than the sum of the outer diameter of the large diameter portion 13 of the core shaft 10 and the outer diameter of the optical fiber 70. Therefore, the optical fiber 70 extending toward the tip along the outer circumferential surface of the large diameter portion 13 of the core shaft 10 is pressed towards the core shaft 10 by the inner circumferential surface of the inner cylindrical body 40 at a position facing the small diameter portion 11 of the core shaft 10. Therefore, according to the guide wire 100 of this embodiment, the presence of the inner cylindrical body 40 improves the tracking ability of the optical fiber 70 when the core shaft 10 deforms, and improves the accuracy of identifying (imaging) the position and shape of the guide wire 100 using the optical fiber 70.

[0040] Furthermore, in the guide wire 100 of this embodiment, at least a portion of the positions along the extension direction of the inner cylindrical body 40, the inner diameter ID40 of the inner cylindrical body 40 coincides with the sum of the outer diameter OD10 of the core shaft 10 and the outer diameter OD70 of the optical fiber 70. Therefore, according to the guide wire 100 of this embodiment, the presence of the inner cylindrical body 40 allows the optical fiber 70 to maintain contact with the core shaft 10, effectively improving the followability of the optical fiber 70 when the core shaft 10 deforms, and effectively improving the accuracy of identifying (imaging) the position and shape of the guide wire 100 using the optical fiber 70.

[0041] Furthermore, in the guide wire 100 of this embodiment, the inner cylindrical body 40 is made of a coil. Therefore, according to the guide wire 100 of this embodiment, the presence of the inner cylindrical body 40 improves the ability of the optical fiber 70 to follow the deformation of the core shaft 10 while suppressing a decrease in the flexibility of the tip of the guide wire 100.

[0042] Furthermore, the guide wire 100 of this embodiment further includes an outer cylindrical body 20 that covers the core shaft 10, the inner cylindrical body 40, and the optical fiber 70. Therefore, according to the guide wire 100 of this embodiment, the optical fiber 70 arranged along the outer circumferential surface of the core shaft 10 can be protected by the outer cylindrical body 20.

[0043] Furthermore, in the guide wire 100 of this embodiment, the tip outer cylindrical body 21 that constitutes the tip of the outer cylindrical body 20 is made of a coil body. Therefore, according to the guide wire 100 of this embodiment, it is possible to suppress a decrease in the flexibility of the tip of the guide wire 100.

[0044] Furthermore, in the guide wire 100 of this embodiment, the base end outer cylindrical body 22 that constitutes the base end of the outer cylindrical body 20 is made of a metal tube. Therefore, the rigidity of the base end of the guide wire 100 can be increased, and the torque transmission and pushability of the guide wire 100 can be improved.

[0045] B. Second Embodiment: Figure 6 is a schematic diagram illustrating the configuration of the guide wire 100a in the second embodiment. Figure 6 shows the configuration of the longitudinal section of the guide wire 100a. In the following, for the configuration of the guide wire 100a in the second embodiment that is the same as that of the guide wire 100 in the first embodiment described above, the same reference numerals are used, and their explanations will be omitted as appropriate.

[0046] The guide wire 100a of the second embodiment differs from the guide wire 100 of the first embodiment in the configuration of the outer cylindrical body 20a. Specifically, in the guide wire 100a of the second embodiment, the base outer cylindrical body 22a of the outer cylindrical body 20a is made of a coil body instead of a tube body. That is, the outer cylindrical body 20a is formed of a coil body along its entire length.

[0047] In this embodiment, the outer cylindrical body 20a has a configuration in which two coil bodies, the tip outer cylindrical body 21 and the base outer cylindrical body 22a, are joined together, but the outer cylindrical body 20a may be composed of a single coil body.

[0048] According to the guide wire 100a of the second embodiment, similar to the guide wire 100 of the first embodiment, the position and shape of the guide wire 100a can be identified (imaged) using the optical fiber 70, while the rigidity of the guide wire 100a can be increased by the presence of the core shaft 10, thereby improving the supportability of the combined device and the bending durability of the tip.

[0049] Furthermore, according to the guide wire 100a of the second embodiment, since the outer cylindrical body 20a is formed by a coil body along its entire length, the rigidity gap of the guide wire 100a can be reduced and kink resistance can be improved.

[0050] C. Third Embodiment: Figures 7 to 9 are schematic explanatory diagrams showing the configuration of the guide wire 100b in the third embodiment. Figure 7 shows the configuration of the longitudinal section of the guide wire 100b, Figure 8 shows the configuration of the cross section of the guide wire 100b at position VIII-VIII in Figure 7, and Figure 9 shows the configuration of the cross section of the guide wire 100b at position IX-IX in Figure 7. In the following, for the configuration of the guide wire 100b in the third embodiment, components that are the same as those of the guide wire 100 in the first embodiment described above will be denoted by the same reference numerals, and their explanations will be omitted as appropriate.

[0051] The guide wire 100b of the third embodiment differs from the guide wire 100 of the first embodiment in the configuration of the core shaft 10b. Specifically, in the guide wire 100b of the third embodiment, the large-diameter portion 13b of the core shaft 10b constitutes the base end of the core shaft 10b, and there is no portion like the second tapered portion 14 in the first embodiment.

[0052] Furthermore, in the guide wire 100b of the third embodiment, grooves 18 are formed on the outer circumferential surface of the large-diameter portion 13b of the core shaft 10b. The grooves 18 are formed along the entire length of the large-diameter portion 13b. The positions of the grooves 18 along the circumferential direction of the core shaft 10b are the same at each position along the extension direction of the core shaft 10b. That is, when the core shaft 10b is viewed from a predetermined direction (the Y-axis direction in the example of Figure 7), the grooves 18 extend in a substantially straight line.

[0053] The depth of the groove 18 is approximately constant from the tip to near the base end of the wide-diameter portion 13b, and more specifically, it is approximately equal to the outer diameter OD70 of the optical fiber 70. However, at the base end of the wide-diameter portion 13b, the groove 18 has a tapered groove portion 19 whose depth gradually increases toward the base end (Figures 7 and 9). In the tapered groove portion 19, the depth of the groove 18 is greater than the outer diameter OD70 of the optical fiber 70.

[0054] The optical fiber 70 is housed in the groove 18 formed in the large-diameter portion 13b of the core shaft 10b. As described above, the depth of the groove 18 is approximately equal to the outer diameter OD70 of the optical fiber 70 from the tip to near the base end of the large-diameter portion 13b, so that almost the entire cross-section of the optical fiber 70 is housed within the groove 18. Therefore, as shown in Figure 8, in the cross-section of the guide wire 100b, the optical fiber 70 is positioned inside the approximately circular cross-section of the large-diameter portion 13b of the core shaft 10b. The inner diameter ID20 of the base end outer cylindrical body 22 of the outer cylindrical body 20 is approximately equal to the outer diameter OD10 of the large-diameter portion 13b of the core shaft 10b. Therefore, there is almost no space between the inner circumferential surface of the base end outer cylindrical body 22 and the outer circumferential surface of the large-diameter portion 13b of the core shaft 10b.

[0055] Furthermore, as shown in Figures 7 and 9, in the tapered groove portion 19 of the groove 18, since the depth of the groove 18 is greater than the outer diameter OD 70 of the optical fiber 70, the optical fiber 70 extends along the bottom surface of the groove 18, approaching the central axis of the core shaft 10b. Note that since grooves 18 are not formed in the first tapered portion 12 and the narrow diameter portion 11 of the core shaft 10b, in these positions, as shown in Figure 3, the optical fiber 70 is positioned outside the substantially circular cross-section of the core shaft 10b.

[0056] As described above, in the guide wire 100b of the third embodiment, a groove 18 is formed on the outer circumferential surface of the core shaft 10b, extending from the base end to the tip end of the core shaft 10b, and at least a portion of the optical fiber 70 along the stretching direction is housed within the groove 18. Therefore, the guide wire 100b of the third embodiment can improve the stability of the position of the optical fiber 70 on the outer circumferential surface of the core shaft 10b, thereby improving the followability of the optical fiber 70 when the core shaft 10b deforms, and improving the accuracy of identifying (imaging) the position and shape of the guide wire 100b using the optical fiber 70. Furthermore, because the optical fiber 70 is housed within the groove 18, the space formed between the core shaft 10b and the outer cylindrical body 20 at the base end of the guide wire 100b can be reduced, thereby suppressing the decrease in rigidity of the guide wire 100b caused by the presence of this space.

[0057] Furthermore, in the guide wire 100b of the third embodiment, the groove 18 at the base end of the core shaft 10b has a tapered groove portion 19 whose depth gradually increases toward the base end. Therefore, compared to a configuration in which the groove 18 does not have a tapered groove portion 19 and the depth of the groove 18 is constant to the base end of the groove 18, the number of places in which the optical fiber 70 bends at a large angle of about 90 degrees can be reduced, thereby reducing the risk of breakage of the optical fiber 70. In addition, since it is only necessary to make the groove 18 tapered, and there is no need to make the core shaft 10b itself tapered, a decrease in the rigidity of the core shaft 10b, and consequently a decrease in the rigidity of the guide wire 100b, can be suppressed.

[0058] D. Variations: The technologies disclosed herein are not limited to the embodiments described above and can be modified in various forms without departing from their essence, for example, the following modifications are possible.

[0059] The configuration of the guide wire 100 in the above embodiment is merely an example and can be modified in various ways. For example, in the first embodiment, the core shaft 10 is composed of a small diameter portion 11, a first tapered portion 12, a large diameter portion 13, and a second tapered portion 14. However, the core shaft 10 may not have at least one of these four portions, or it may have other portions in addition to these four portions. For example, the core shaft 10 may not have the second tapered portion 14. The same applies to the core shaft 10 in other embodiments.

[0060] In the above embodiment, the positions of the optical fibers 70 along the circumferential direction of the core shaft 10 are the same at each position along the extension direction of the core shaft 10. However, the positions of the optical fibers 70 along the circumferential direction of the core shaft 10 may be different at each position along the extension direction of the core shaft 10. For example, the optical fibers 70 may be arranged to be spirally wound around the core shaft 10.

[0061] In the third embodiment described above, the groove 18 is formed along the entire length of the large-diameter portion 13b of the core shaft 10b, but the groove 18 may be formed only in a part of the large-diameter portion 13b. Also, the groove 18 does not have to have a tapered groove portion 19. Also, the groove 18 may be formed in parts of the core shaft 10b other than the large-diameter portion 13b. Furthermore, in the third embodiment described above, the positions of the groove 18 along the circumferential direction of the core shaft 10b are the same at each position along the extension direction of the core shaft 10b, but the positions of the groove 18 along the circumferential direction of the core shaft 10b may be different at each position along the extension direction of the core shaft 10b. Also, in the first and second embodiments described above, similar to the third embodiment, the groove 18 may be formed in the core shaft 10, and the optical fiber 70 may be housed in the groove 18.

[0062] In the third embodiment described above, the entire cross-section of the optical fiber 70 is housed within the groove 18 in the portion of the optical fiber 70 facing the groove 18 in the large-diameter portion 13b, but it is also possible for only a portion of the cross-section to be housed within the groove 18.

[0063] In the above embodiment, at each position along the extension direction of the inner cylindrical body 40, the inner diameter ID40 of the inner cylindrical body 40 is approximately equal to the sum of the outer diameter OD10 of the core shaft 10 and the outer diameter OD70 of the optical fiber 70. However, at some or all positions along the extension direction of the inner cylindrical body 40, the inner diameter ID40 of the inner cylindrical body 40 may be greater than this sum. Furthermore, in the above embodiment, the inner cylindrical body 40 is composed of a coil, but the inner cylindrical body 40 may be composed of a tube having a uniform cross-section instead of a coil.

[0064] In the guide wire 100 of the above embodiment, at least one component may be omitted. For example, in the guide wire 100 of the above embodiment, at least one of the inner cylindrical body 40 and the outer cylindrical body 20 may be omitted. Also, the materials of each component in the above embodiment are merely examples and can be modified in various ways. [Explanation of symbols]

[0065] 10: Core shaft 11: Thin section 12: First tapered section 13: Wide section 14: Second tapered section 18: Groove 19: Tapered groove section 20: Outer cylindrical body 21: Tip outer cylindrical body 22: Base outer cylindrical body 24: Space 26: Space 40: Inner cylindrical body 41: Thin section 42: Tapered section 43: Wide section 50: Tip joint 60: Base cylindrical body 62: Lumen for optical fiber 70: Optical fiber 100: Guide wire

Claims

1. A guidewire comprising: A core shaft; A first tubular body disposed proximal to the core shaft and having a first lumen; an optical fiber passing through the first lumen and extending along an outer circumferential surface of the core shaft toward a distal end side of the core shaft; a tip joint portion that joins a tip of the core shaft and a tip of the optical fiber; Equipped with Guidewire.

2. 2. The guidewire of claim 1, The core shaft has a tapered shaft portion that constitutes a base end portion of the core shaft and has an outer diameter that gradually decreases toward the base end side. Guidewire.

3. The guidewire according to claim 1 or 2, A groove is formed on an outer circumferential surface of the core shaft, the groove extending from a base end of the core shaft to a tip end thereof, At least a portion of the optical fiber along the extending direction is accommodated in the groove, At the base end of the core shaft, the groove has a tapered groove portion whose depth gradually increases toward the base end side. Guidewire.

4. The guidewire according to any one of claims 1 to 3, The core shaft includes: A large diameter portion; a thin diameter portion located on the tip side of the thick diameter portion and having an outer diameter smaller than that of the thick diameter portion; having The guide wire further includes a second tubular body that covers at least the thin-diameter portion of the core shaft and the tip end of the optical fiber, and the inner diameter of the portion that covers the thin-diameter portion is smaller than the sum of the outer diameter of the thick-diameter portion of the core shaft and the outer diameter of the optical fiber. Guidewire.

5. 5. The guidewire of claim 4, At least in a portion of a position along an extension direction of the second cylindrical body, an inner diameter of the second cylindrical body is equal to a sum of an outer diameter of the core shaft and an outer diameter of the optical fiber. Guidewire.

6. A guidewire according to any one of claims 1 to 3, The core shaft includes: A large diameter portion; a thin diameter portion located on the tip side of the thick diameter portion and having an outer diameter smaller than that of the thick diameter portion; having the guidewire further includes a second tubular body covering at least the small diameter portion of the core shaft and the tip end of the optical fiber; The inner circumferential surface of the second cylindrical body is in contact with the outer circumferential surface of the optical fiber. Guidewire.

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