Inserter

Abstract

An inserter 10 comprises: an outer cylinder 1 which has a first slit 11 extending from a tip end 112 to a base end 111 and has a first mating part 12 provided on an inner peripheral surface; and an inner cylinder 2 which is disposed inside the outer cylinder 1, is configured to be rotatable in a circumferential direction relative to the outer cylinder 1, has a second slit 21 extending from a tip end 212 to a base end 211, and has a second mating part 22 provided on an outer peripheral surface and with which the first mating part 12 mates. In a first state where the first slit 11 and the second slit 21 overlap, the first mating part 12 mates with the second mating part 22 at a first position. In a second state where the first slit 11 and the second slit 21 do not overlap, the first mating part 12 mates with the second mating part 22 at a second position. The inserter 10 described above, despite having the slits formed therein for facilitating attachment / detachment to / from a guide wire, can prevent the guide wire from jumping out or falling off from the slits.

Description

Inserter

[0001] The present disclosure relates to an inserter used to introduce an insert such as a guidewire into a tubular medical device such as a catheter.

[0002] Conventionally, guidewires have been used to guide medical instruments, such as catheters, inserted into tubular organs of the human body, such as blood vessels and digestive organs, to target sites. Known guidewires have distal ends formed into a curved shape or the like depending on the application. When inserting such guidewires into tubular organs, catheters, or the like, physicians use an insertion aid called an inserter, which has a tubular portion through which the guidewire is inserted, so that the distal end can be inserted in a substantially straight state (see, for example, Patent Document 1).

[0003] When an inserter is attached to a guidewire, the distal end of the guidewire is typically inserted into the proximal end of the tubular portion of the inserter. When removing the inserter from the guidewire, if the distal end of the guidewire is already inserted into a tubular organ, catheter, or the like, the inserter must be moved to the proximal end of the guidewire. After removing the inserter from the guidewire, it may be necessary to reattach the inserter. In this case, too, the inserter must be attached from the proximal end of the guidewire and then moved to the distal end of the guidewire. Therefore, inserters with slits in the tubular portion have been used to facilitate attachment and detachment of the inserter from the distal end of the guidewire (see, for example, Patent Documents 2 and 3).

[0004] Japanese Patent Application Laid-Open No. 2000-107297 Japanese Patent Application Laid-Open No. 2004-242954 Japanese Patent Application Laid-Open No. 2005-245514

[0005] Although providing a slit in the tubular portion of the inserter makes it easier to attach and detach it from the guidewire, there is a risk that the tip of the guidewire may come out of the slit during operation, or that the inserter may unintentionally come off the guidewire.

[0006] The present disclosure has been made in consideration of the above circumstances, and aims to provide an inserter that has a slit that makes it easy to attach and detach an insert such as a guide wire, while preventing the insert from popping out or falling out of the slit.

[0007] In order to achieve the above-mentioned object, the present disclosure provides an inserter comprising: an outer tube having a first slit extending from a distal end to a proximal end and a first fitting portion provided on an inner peripheral surface; and an inner tube disposed inside the outer tube, configured to be rotatable in a circumferential direction relative to the outer tube, the inner tube having a second slit extending from a distal end to a proximal end and a second fitting portion provided on the outer peripheral surface with which the first fitting portion fits; wherein in a first state in which the outer tube and the inner tube are positioned such that the first slit and the second slit overlap, the first fitting portion fits with the second fitting portion at a first position; and in a second state in which the outer tube and the inner tube are positioned such that the first slit and the second slit do not overlap, the first fitting portion fits with the second fitting portion at a second position.

[0008] According to this disclosure, in a first state in which the inner tube is positioned inside the outer tube so that the first slit of the outer tube and the second slit of the inner tube overlap, the inserter can be easily attached to and detached from an insert such as a guidewire. Changing the position in which the first fitting portion and the second fitting portion are fitted from the first position to the second position switches the positional relationship between the outer tube and the inner tube from the first state to a second state in which the first slit and the second slit do not overlap. In the second state in which the first slit and the second slit do not overlap, the insert can be prevented from popping out or falling out of the slit during use. This achieves an inserter that has a slit that facilitates attachment and detachment to and from an insert, yet can prevent the insert from popping out or falling out of the slit.

[0009] FIG. 1 is an explanatory diagram showing the overall structure of an inserter according to an embodiment of the present disclosure; FIG. 2 is an explanatory diagram showing the cross-sectional structure of the inserter according to the embodiment; FIG. 3 is an explanatory diagram showing the appearance of the outer tube of the inserter according to the embodiment; FIG. 4 is an explanatory diagram showing the cross-sectional structure of the outer tube of the inserter according to the embodiment; FIG. 5 is an explanatory diagram showing the appearance of the inner tube of the inserter according to the embodiment; FIG. 6 is an explanatory diagram showing the cross-sectional structure of the inner tube of the inserter according to the embodiment; FIG. 7 is an explanatory diagram showing the positional relationship between the outer tube and the inner tube in a first state; FIG. 8 is an explanatory diagram showing how the positional relationship between the outer tube and the inner tube begins to transition from the first state to a second state by pushing the inner tube into the outer tube; FIG. 9 is an explanatory diagram showing the positional relationship between the outer tube and the inner tube in a second state; FIG. 10 is an explanatory diagram showing a state in which the first slit and the second slit overlap; and FIG. 11 is an explanatory diagram showing a state in which the first slit and the second slit do not overlap.

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the embodiments described below, and the described embodiments are merely examples for explaining the technical features of the present disclosure. The shapes and dimensions shown in each drawing are shown merely to facilitate understanding of the contents of the present disclosure, and do not accurately reflect the actual shapes and dimensions.

[0011] As used herein, "distal" refers to the direction along the axial direction of the inserter (and the insert, such as a guidewire to which the inserter is attached) in which the inserter (and the insert, such as a guidewire) advances toward the target site. "Proximal" refers to the direction along the axial direction of the inserter (and the insert, such as a guidewire) in the opposite direction from the distal end. "Distal" refers to the distal end of any component or component, and "proximal" refers to the proximal end of any component or component.

[0012] FIG. 1 is an explanatory diagram showing the overall structure of an inserter 10 according to one embodiment of the present disclosure, and FIG. 2 is an explanatory diagram (longitudinal cross-sectional view) showing the cross-sectional structure of the inserter 10 according to the same embodiment. The inserter 10 according to this embodiment includes a substantially cylindrical outer tube 1 and a substantially cylindrical inner tube 2 that is disposed inside the outer tube 1 and configured to be rotatable in the circumferential direction relative to the outer tube 1. The inserter 10 is an insertion aid used to insert an insert such as a guidewire or a thin-diameter catheter into a tubular organ, a catheter, or the like. In this embodiment, a guidewire GW will be described as an example of the insert.

[0013] The outer cylinder 1 has a first slit 11 extending from the distal end 112 to the proximal end 111, and a groove 12 serving as a first fitting portion is provided on its inner peripheral surface so as to extend from the proximal end 111 toward the distal end. The inner cylinder 2 has a second slit 21 extending from the distal end 212 to the proximal end 211, and a protrusion 22 serving as a second fitting portion is provided on its outer peripheral surface so as to protrude outward from the outer peripheral surface, into which the groove 12 (first fitting portion) of the outer cylinder 1 fits.

[0014] Figure 3 is an explanatory diagram showing the appearance of the outer tube 1 that constitutes the inserter 10, and Figure 4 is an explanatory diagram (longitudinal cross-sectional view) showing the cross-sectional structure of the outer tube 1. The outer tube 1 comprises a roughly cylindrical outer tube main body 1A and a roughly cylindrical first tube 1B attached to the tip of the outer tube main body 1A. The internal space of the outer tube main body 1A and the internal space of the first tube 1B are connected to each other, forming the inner cavity 13 of the outer tube 1.

[0015] The outer tube 1 has a first slit 11 extending in the axial direction (longitudinal direction) from the distal end 112 to the proximal end 111. The first slit 11 is a cut formed in the axial direction of the outer tube 1 across both the outer tube body 1A and the first tube 1B, and a gap may be formed between both end edges of the first slit 11, or the both end edges may overlap. The formation of the first slit 11 in the outer tube 1 of the inserter 10 makes it possible to introduce the guidewire GW from the side circumferential surface of the outer tube 1 into the lumen 13 inside the outer tube 1.

[0016] A groove 12 serving as a first fitting portion is provided on the inner peripheral surface of the outer tube body 1A of the outer tube 1, extending from the base end 111 toward the tip. The groove 12 is formed in a spiral shape on the inner peripheral surface of the outer tube body 1A at a position that does not overlap with the first slit 11. The groove 12 does not necessarily have to be formed in a spiral shape, as long as it is provided so as to extend from the base end 111 toward the tip and is formed while being offset in the circumferential direction of the outer tube 1.

[0017] Examples of materials for forming the outer tube 1 include resin materials such as polyamide, polyamide elastomer, polyolefin, polyester, and polyester elastomer. The entire outer tube 1 may be formed from the same material, or the outer tube body 1A and the first tube 1B of the outer tube 1 may be formed from different materials. By forming the outer tube 1 from a resin material, the first slit 11 and the groove portion 12 can be easily formed in the outer tube 1.

[0018] Figure 5 is an explanatory diagram showing the appearance of the inner tube 2 that constitutes the inserter 10, and Figure 6 is an explanatory diagram (longitudinal cross-sectional view) showing the cross-sectional structure of the inner tube 2. The inner tube 2 comprises a substantially cylindrical inner tube main body 2A and a substantially cylindrical second tube 2B attached to the tip of the inner tube main body 2A. The internal space of the inner tube main body 2A and the internal space of the second tube 2B are in communication with each other, forming the inner cavity 23 of the inner tube 2.

[0019] The inner tube 2 has a second slit 21 extending in the axial direction (longitudinal direction) from the distal end 212 to the proximal end 211. The second slit 21 is a cut formed in the axial direction of the inner tube 2 across both the inner tube body 2A and the second tube 2B, and a gap may be formed between both end edges of the second slit 21, or the both end edges may overlap. By forming the second slit 21 in the inner tube 2 of the inserter 10, the guidewire GW can be introduced from the side circumferential surface of the inner tube 2 into the lumen 23 inside the inner tube 2.

[0020] The inner cylinder 2 is disposed inside the outer cylinder 1 and is configured to be rotatable in the circumferential direction relative to the outer cylinder 1. In this embodiment, the outer diameter of the inner cylinder 2 is formed to be slightly smaller than the inner diameter of the outer cylinder 1. This is not a limitation as long as the inner cylinder 2 is rotatable inside the outer cylinder 1. For example, even if the outer diameter of the inner cylinder 2 is approximately the same as the inner diameter of the outer cylinder 1, the inner cylinder 2 may be disposed inside the outer cylinder 1 and configured to slide inside the outer cylinder 1 by utilizing the first slit 11 formed in the outer cylinder 1.

[0021] A protrusion 22 serving as a second fitting portion is provided on the outer peripheral surface of the inner cylinder main body 2A of the inner cylinder 2 so as to protrude outward from the outer peripheral surface. The protrusion 22 is formed in a substantially cylindrical shape on the outer peripheral surface of the inner cylinder main body 2A at a position that does not overlap with the second slit 21. Since the cross section of the protrusion 22 is circular, when the protrusion 22 fitted in the groove 12 moves along the groove 12, the protrusion 22 is prevented from getting caught on the side wall of the groove 12, thereby realizing smooth movement of the protrusion 22 within the groove 12. The protrusion 22 does not necessarily have to have a substantially cylindrical shape with a circular cross section. As long as it can move within the groove 12, it may be in the shape of a rectangular parallelepiped, a cube, a hemisphere, a cone, a pyramid, or the like.

[0022] Examples of materials that can be used to form the inner tube 2 include resin materials such as polyamide, polyamide elastomer, polyolefin, polyester, and polyester elastomer. The entire inner tube 2 may be made of the same material, or the inner tube body 2A and the second tube 2B of the inner tube 2 may be made of different materials. By forming the inner tube 2 from a resin material, the second slits 21 and the protrusions 22 can be easily formed in the inner tube 2.

[0023] When the positional relationship between the outer tube 1 and the inner tube 2 is in a first state in which the first slit 11 and the second slit 21 overlap, the groove 12 serving as the first fitting portion fits with the protrusion 22 serving as the second fitting portion in the first position. When the positional relationship between the outer tube 1 and the inner tube 2 is in a second state in which the first slit 11 and the second slit 21 do not overlap, the groove 12 serving as the first fitting portion fits with the protrusion 22 serving as the second fitting portion in the second position. In this embodiment, the first fitting portion is the groove 12 extending from the base end of the outer tube 1 toward the tip, and the second fitting portion is the protrusion 22 protruding outward from the outer peripheral surface of the inner tube 2. In another embodiment, the first fitting portion may be a protrusion protruding inward from the inner peripheral surface of the outer tube 1, and the second fitting portion may be a groove extending from the tip of the inner tube 2 toward the base end.

[0024] With this inserter 10, in a first state in which the inner tube 2 is positioned inside the outer tube 1 so that the first slit 11 of the outer tube 1 overlaps the second slit 21 of the inner tube 2, the inserter 10 can be easily attached to and detached from an insert such as a guidewire. Changing the position in which the first and second fitting portions are fitted from the first position to the second position switches the positional relationship between the outer tube 1 and the inner tube 2 from the first state to a second state in which the first slit 11 and the second slit 21 do not overlap. In the second state in which the first slit 11 and the second slit 21 do not overlap, the insert is prevented from popping out or falling out of the slit during use.

[0025] 7, 8, and 9, a description will be given of how the inserter 10 is attached to the guidewire GW with the inner tube 2 disposed inside the outer tube 1. In FIGS. 7, 8, and 9, only the outer tube 1 is shown in cross section so that the positional relationship between the outer tube 1 and the inner tube 2 can be seen.

[0026] Figure 7 shows the inserter 10 with the positional relationship between the outer tube 1 and the inner tube 2 in a first state. When the tip 212 of the inner tube 2 is inserted from the base end 111 of the outer tube 1 and the inner tube 2 is inserted into the lumen 13 of the outer tube 1, the protrusion 22 of the inner tube 2 fits into the groove 12 of the outer tube 1. The position shown in Figure 7 where the protrusion 22 of the inner tube 2 fits into the groove 12 of the outer tube 1 at the most base end side is the first position of the present disclosure. In the first state where the first slit 11 of the outer tube 1 and the second slit 12 of the inner tube 2 overlap, the guidewire GW can be pushed into the inserter 10 (the outer tube 1 and the inner tube 2) from the side circumferential surface thereof.

[0027] 8 shows how the positional relationship between the outer tube 1 and the inner tube 2 begins to transition from a first state to a second state as the inner tube 2 is pushed into the outer tube 1. The groove 12 of the outer tube 1 is formed straight in the axial direction from the base end 111 of the outer tube 1 for a while, and then forms a spiral shape so as to rotate circumferentially. First, the user pushes the guidewire GW into the inserter 10 (the outer tube 1 and the inner tube 2) from the side surface of the inserter 10, attaching the inserter 10 to the guidewire GW. In this state, if the user continues to push the inner tube 2 toward the distal end of the outer tube 1, the protrusion 22 of the inner tube 2 moves along the groove 12 of the outer tube 1, and the inner tube 2 advances toward the distal end of the outer tube 1 while rotating clockwise.

[0028] Figure 9 shows the inserter 10 in a second position relative to the outer tube 1 and inner tube 2. As the user continues to push the inner tube 2 toward the distal end of the outer tube 1, the protrusion 22 of the inner tube 2 reaches the distal-most side of the groove 12 of the outer tube 1. The position shown in Figure 9, in which the protrusion 22 of the inner tube 2 is fitted into the distal-most side of the groove 12 of the outer tube 1, is the second position of the present disclosure. In the second position, in which the first slit 11 of the outer tube 1 and the second slit 21 of the inner tube 2 do not overlap, the user cannot remove the guidewire GW inside the inserter 10 from the inserter 10. In the second position, the guidewire GW is prevented from jumping out or falling out of the slit of the inserter 10 during use.

[0029] Fig. 10 is an explanatory diagram showing a state in which the first slit 11 and the second slit 21 overlap, and Fig. 11 is an explanatory diagram showing a state in which the first slit 11 and the second slit 21 do not overlap. Fig. 10 schematically shows a cross section of the inserter 10 in which the outer tube 1 and the inner tube 2 are positioned in a first state (the state shown in Fig. 7), in which the first slit 11 of the outer tube 1 overlaps the second slit 21 of the inner tube 2. Because the first slit 11 of the outer tube 1 and the second slit 21 of the inner tube 2 open in the same direction, the guidewire GW can be inserted into and removed from the inserter 10.

[0030] When the inner tube 2 rotates inside the outer tube 1, it reaches the state shown in Figure 11. Figure 11 schematically shows a cross section of the inserter 10 when the positional relationship between the outer tube 1 and the inner tube 2 is in the second state (the state shown in Figure 9), in which the first slit 11 of the outer tube 1 and the second slit 21 of the inner tube 2 do not overlap. Because the first slit 11 of the outer tube 1 and the second slit 21 of the inner tube 2 do not open in the same direction, the guidewire GW cannot be inserted or removed from inside the inserter 10.

[0031] As described above, in the inserter 10 according to this embodiment, by pushing the inner tube 2 into the outer tube 1, the protrusion 22 of the inner tube 2 moves from the first position to the second position in the groove 12 of the outer tube 1. As the protrusion 22 moves from the first position to the second position, the positional relationship between the outer tube 1 and the inner tube 2 transitions from a first state to a second state. That is, by simply moving the protrusion 22 from the first position to the second position, the inserter 10 can transition the positional relationship between the outer tube 1 and the inner tube 2 from the first state, in which the first slit 11 of the outer tube 1 and the second slit 21 of the inner tube 2 overlap, to the second state, in which the first slit 11 and the second slit 21 do not overlap. This prevents the guidewire GW from jumping out or falling off the slit, even though a slit that facilitates attachment and detachment of the guidewire GW is formed.

[0032] In particular, by adopting a structure in which the groove 12 of the outer cylinder 1 is formed in a spiral shape and the protrusion 22 of the inner cylinder 2 is fitted into the groove 12, the inner cylinder 2 can be rotated in the circumferential direction relative to the outer cylinder 1 simply by pushing and pulling the inner cylinder 2 relative to the outer cylinder 1. By pushing and pulling the inner cylinder 2 relative to the outer cylinder 1, it is possible to easily switch between a first state in which the first slit 11 of the outer cylinder 1 and the second slit 21 of the inner cylinder 2 overlap, and a second state in which the first slit 11 and the second slit 21 do not overlap.

[0033] When inserting the inner tube 2 into the lumen 13 of the outer tube 1, simply fitting the protrusion 22 of the inner tube 2 into the base end side of the groove 12 formed in the outer tube 1 achieves a first state in which the first slit 11 of the outer tube 1 and the second slit 21 of the inner tube 2 overlap, so the groove 12 and the protrusion 22 also function as alignment guides. Alignment is made easier by forming the groove 12 in a straight line in the axial direction for a while from the base end 111 of the outer tube 1. The relative rotation angle of the inner tube 2 with respect to the outer tube 1 can also be controlled by changing how far the groove 12 is rotated circumferentially on the inner peripheral surface of the outer tube 1.

[0034] The inserter according to the present disclosure has been described above with reference to the drawings. The present disclosure is not limited to the above-described embodiment and various modifications are possible. For example, the outer tube of the inserter may consist of only the outer tube body, with no tube body attached to the tip of the outer tube body, or the inner tube of the inserter may consist of only the inner tube body, with no tube body attached to the tip of the inner tube body. The inner and outer diameters of the outer and inner tube bodies, the first and second tubes, etc. may be constant, or may have portions with different inner and outer diameters.

[0035] The present disclosure provides an inserter comprising: an outer tube having a first slit extending from a distal end to a proximal end and a first fitting portion provided on an inner peripheral surface; and an inner tube disposed inside the outer tube, configured to be rotatable in a circumferential direction relative to the outer tube, the inner tube having a second slit extending from a distal end to a proximal end and a second fitting portion provided on the outer peripheral surface with which the first fitting portion fits; wherein in a first state in which the outer tube and the inner tube are positioned such that the first slit and the second slit overlap, the first fitting portion fits with the second fitting portion at a first position; and in a second state in which the outer tube and the inner tube are positioned such that the first slit and the second slit do not overlap, the first fitting portion fits with the second fitting portion at a second position (Disclosure 1).

[0036] According to this disclosure (Disclosure 1), in a first state in which the inner tube is disposed inside the outer tube so that the first slit of the outer tube and the second slit of the inner tube overlap, the inserter can be easily attached to and detached from an insert such as a guidewire. Changing the engagement position between the first fitting portion and the second fitting portion from the first position to the second position switches the positional relationship between the outer tube and the inner tube from the first state to a second state in which the first slit and the second slit do not overlap. In the second state in which the first slit and the second slit do not overlap, the insert can be prevented from popping out or falling out of the slit during use. This achieves an inserter that has a slit that facilitates attachment and detachment to and from an insert, yet prevents the insert from popping out or falling out of the slit.

[0037] In the above disclosure (Disclosure 1), the first fitting portion may be a groove portion extending from the base end of the outer tube toward the tip end, and the second fitting portion may be a protrusion portion protruding outward from the outer peripheral surface of the inner tube (Disclosure 2), or the first fitting portion may be a protrusion portion protruding inward from the inner peripheral surface of the outer tube, and the second fitting portion may be a groove portion extending from the tip of the inner tube toward the base end (Disclosure 3).

[0038] According to such disclosures (Disclosures 2 and 3), an interlocking state between the first interlocking portion and the second interlocking portion between the outer tube and the inner tube can be created by interlocking a groove provided on the outer tube with a protrusion provided on the inner tube, or by interlocking a protrusion provided on the outer tube with a groove provided on the inner tube.

[0039] In the above disclosures (Disclosures 2 and 3), it is preferable that the positional relationship between the outer tube and the inner tube transitions from the first state to the second state when the protrusion moves from the first position to the second position (Disclosure 4).

[0040] According to this disclosure (Disclosure 4), simply by moving the protrusion from the first position to the second position, the positional relationship between the outer tube and the inner tube can be transitioned from a first state in which the first slit of the outer tube and the second slit of the inner tube overlap, to a second state in which the first slit and the second slit do not overlap.

[0041] In the above disclosures (Disclosures 2-4), it is preferable that the cross section of the protrusion has a circular shape (Disclosure 5).

[0042] According to this disclosure (Disclosure 5), the protrusion is prevented from getting caught on the side wall of the groove, and smooth movement of the protrusion within the groove can be achieved.

[0043] In the above disclosures (Disclosure 2-5), it is preferable that the groove portion is formed in a spiral shape (Disclosure 6).

[0044] According to this disclosure (Disclosure 6), the inner tube can be rotated circumferentially relative to the outer tube simply by pushing and pulling the inner tube against the outer tube, and it is possible to easily switch between a first state in which the first slit of the outer tube and the second slit of the inner tube overlap, and a second state in which the first slit and the second slit do not overlap.

Claims

1. An outer tube (1) having a first slit (11) extending from a tip (112) to a base end (111) and having a first fitting portion (12) on its inner peripheral surface; and an inner tube (2) arranged inside the outer tube (1) and configured to be rotatable in the circumferential direction relative to the outer tube (1), having a second slit (21) extending from a tip (212) to a base end (211) and having a second fitting portion (22) on its outer peripheral surface with which the first fitting portion (12) fits; in a first state in which the outer tube (1) and the inner tube (2) are in a positional relationship in which the first slit (11) and the second slit (21) overlap, the first fitting portion (12) fits into the second fitting portion (22) at a first position; In a second state in which the outer tube (1) and the inner tube (2) are in a positional relationship in which the first slit (11) and the second slit (21) do not overlap, the first fitting portion (12) fits into the second fitting portion (22) at a second position.

2. An inserter (10) as described in claim 1, wherein the first fitting portion (12) is a groove portion (12) extending from the base end (111) of the outer tube (1) toward the tip, and the second fitting portion (22) is a protrusion portion (22) protruding outward from the outer peripheral surface of the inner tube (2).

3. An inserter (10) as described in claim 1, wherein the first fitting portion (12) is a protrusion that protrudes inward from the inner surface of the outer tube (1), and the second fitting portion (22) is a groove that extends from the tip (212) of the inner tube (2) toward the base end.

4. An inserter (10) as described in claim 2 or 3, wherein the positional relationship between the outer tube (1) and the inner tube (2) transitions from the first state to the second state when the protrusion (22) moves from the first position to the second position.

5. An inserter (10) according to any one of claims 2 to 4, wherein the cross section of the protrusion (22) has a circular shape.

6. An inserter (10) according to any one of claims 2 to 5, wherein the groove (12) is formed in a spiral shape.

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