Microcatheter inserter

Abstract

To provide an inserter for a microcatheter having a guide wire insertion assisting function and capable of functioning as a torquer for operating a guide wire after inserting the guide wire.SOLUTION: A microcatheter inserter 100 according to the present invention includes a base member 10, a guide wire fixture 20 inserted into a hollow portion of the base member 10 from a distal end side and having a pressing portion 22 capable of changing a center diameter at a distal end, and a cap 30 having a screw groove inner peripheral surface having a screw groove screwed with a screw groove of the base member 10, a tapered surface connected to the screw groove inner peripheral surface, and a distal end cylindrical portion connected to the tapered surface. A tip pin 40 having a pin hole of ≤ 0. 5mm at the center and a spring 50 for energizing the tip pin 40 to the tip side are provided.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an inserter for a microcatheter, and more particularly to an inserter that functions as an insertion aid when inserting a guidewire into a microcatheter, and can also function as a torquer when fixed to the inserted guidewire. [Background technology]

[0002] Traditionally, treatment of blood vessels and other lumens has been performed using catheters, and in many cases, a guidewire is used in combination. This guidewire is inserted into the treatment site before the catheter, and the catheter is advanced to the treatment site along the guidewire. Furthermore, in catheter treatments for peripheral blood vessels, thin microcatheters are used, and the guidewires used in combination with these microcatheters are also thin and very flexible instruments.

[0003] Among the treatments for peripheral blood vessels is vascular embolization, which involves inserting a catheter along a guidewire and reaching the treatment site, then removing the guidewire and injecting an embolic coil or embolic substance into the treatment site through the catheter to embolize it. If there are multiple embolized sites, the guidewire is reinserted from the connector on the proximal side of the catheter, and the guidewire is passed through to the next treatment site. The catheter is then extended to reach the next treatment site, and the blood vessels are embolized in the same manner. This process is repeated to treat multiple sites.

[0004] When a guidewire is advanced to a peripheral site, it is necessary to manipulate the guidewire at many branching points and select and advance the blood vessels that lead to the target treatment site. To make this selection easier for the user, a bent portion is formed at the tip of the guidewire. This bent portion makes it easier for the tip of the guidewire to hook onto the desired blood vessel, making it easier to advance to the treatment site. The operation of hooking the bent portion of the guidewire onto the branching blood vessel is performed by rotating the guidewire. However, because guidewires are very thin and slippery, they are manipulated using a device called a torquer, which serves as a gripping part for the guidewire and improves rotational operability.

[0005] The process of reinserting a very thin and flexible guidewire with a bent tip into a microcatheter can be extremely difficult, cumbersome, and time-consuming. In emergency treatments where every second counts, any delay in reinsertion can affect the patient's condition, so users strive to reinsert the guidewire quickly.

[0006] To solve this problem, various inserters have been proposed as guidewire introduction aids (for example, Patent Document 1). Such inserters have an inner lumen through which a guidewire can be inserted, an attachment part at one end of the lumen that is attached to the tip of a catheter, and an opening at the other end for introducing the guidewire, and the attachment part has an outer diameter that allows it to be inserted and fitted into the lumen of the catheter from the catheter tip.

[0007] Such an inserter has the advantage of facilitating the operation of introducing a guidewire into a catheter inserted into a living body, eliminating the risk of the guidewire getting caught during the introduction operation, and being structured to make it difficult for the guidewire to become dislodged from the catheter. However, such an inserter has the disadvantage that the corresponding attachment part must have an outer diameter that allows it to be inserted and fitted into the lumen of the catheter from the catheter tip, and therefore cannot be used universally for catheters with different inner diameters.

[0008] Furthermore, when manipulating a guidewire introduced by a conventional inserter, a guidewire manipulation device called a torquer must be attached again, which has the drawback of requiring the inserter to be removed first and then the torquer to be attached to the proximal end of the guidewire. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-315836 Summary of the Invention [Problem to be solved by the invention]

[0010] An object of the present invention is to provide a microcatheter inserter that has the function of assisting in the insertion of a guidewire when inserting it from a connector on the base end side of a catheter, particularly a microcatheter, and that can also function as a torquer to manipulate the guidewire after it has been inserted. [Means for solving the problem]

[0011] In order to achieve the above object, the present invention employs the following means.

[0012] The microcatheter inserter according to the present invention comprises: a hollow base member having a screw groove formed on the outer periphery of the tip end thereof; a guidewire fixing device that is inserted into the hollow portion of the base member from the distal end side and has a pressing portion at the distal end that can change the inner diameter of the guidewire passage hole; a cap having a thread groove inner peripheral surface having a thread groove that screws into the thread groove of the base member, an abutment surface that contacts the thread groove inner peripheral surface, and a tip cylindrical portion that contacts the abutment surface; a tip pin disposed in the tip cylindrical portion of the cap and having a pin hole of 0.5 mm or less in the center; an elastic member that biases the tip pin toward the tip side; The present invention is characterized by the following.

[0013] With the microcatheter inserter of the present invention, simply by inserting the tip pin into the insertion hole of the connector, the tip of the tip pin can be set in the introduction port of the microcatheter at the back of the connector, and the guide wire can be inserted into the microcatheter by inserting it from the rear end of the base member. Furthermore, after insertion, the guide wire can be fixed and used as a torquer as is.

[0014] The microcatheter inserter according to the present invention comprises: a hollow base member having a screw groove formed on the outer periphery of the tip end thereof; a guidewire fixing device that is inserted into the hollow portion of the base member from the distal end side and has a pressing portion at the distal end that can change the inner diameter of the guidewire passage hole; a cap having a thread groove inner peripheral surface having a thread groove that screws into the thread groove of the base member, an abutment surface that contacts the thread groove inner peripheral surface, and a tip cylindrical portion that contacts the abutment surface; a tip pin disposed in the tip cylindrical portion of the cap and having a pin hole of 0.5 mm or less in the center, The tip tube portion is characterized in that it is made so as to be able to hold the tip pin in a predetermined position.

[0015] According to the catheter of the present invention, the tip pin can be held in a predetermined position, so that the catheter can be used without incurring the load of moving the position of the tip pin when reinserting the guide wire.

[0016] Furthermore, in the microcatheter inserter according to the present invention, the taper angle of the tip pin may be smaller than the taper angle of the insertion hole of the connector. By adopting this configuration, the tip pin can be inserted deep into the tapered hole of the connector.

[0017] Furthermore, in the microcatheter inserter according to the present invention, the distal tube portion may have a step formed midway, and the distal pin may have an engaging portion formed with a diameter larger than the outer periphery of the surrounding area so as to engage with the step. By adopting such a configuration, the engaging portion of the distal pin can be prevented from getting caught on the step and coming off the distal end of the microcatheter inserter.

[0018] Furthermore, in the microcatheter inserter according to the present invention, the cap may have a positioning surface that comes into surface contact with the end face of the connector of the microcatheter to be inserted. By adopting such a configuration, the microcatheter inserter can be positioned, the hole of the tip pin can be arranged parallel to the central axis, and the guidewire can be easily inserted.

[0019] Furthermore, in the microcatheter inserter according to the present invention, the cap may have an outer peripheral surface that fits with the inner peripheral surface of the insertion hole of the connector of the microcatheter to be inserted. By adopting such a configuration, the microcatheter inserter can be more reliably positioned, the hole of the tip pin can be arranged parallel to the central axis, and the guidewire can be easily inserted.

[0020] Furthermore, in the microcatheter inserter according to the present invention, the tip of the inner peripheral surface of the tip pin may be characterized by being curved. By adopting such a configuration, when used as a torquer, it is possible to prevent damage to the guidewire when rotating the torquer. [Effects of the Invention]

[0021] The microcatheter inserter of the present invention can provide a microcatheter inserter that has the function of assisting in the insertion of a guidewire from the connector on the base end side of the catheter, and can also function as a torquer to manipulate the guidewire after it has been inserted. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a side view of a microcatheter inserter 100 according to the first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the microcatheter inserter 100 according to the first embodiment. [Figure 3] FIG. 3 is a cross-sectional view showing a state when the microcatheter inserter 100 according to the first embodiment is inserted into the insertion hole of the connector. [Figure 4] FIG. 4 is an explanatory diagram for explaining the taper angle c (angle with respect to the central axis) of the tip of the tip pin 40 of the microcatheter inserter 100 according to the first embodiment and the taper angle d of the insertion hole 83 of the connector 81. [Figure 5] FIG. 5 is a side view of the microcatheter inserter 100 according to the second embodiment. [Figure 6] FIG. 6 is a reference diagram showing the state in which a guide wire 90 is inserted into a connector using a microcatheter inserter 100 according to the present invention. [Figure 7] FIG. 7 is a reference diagram showing a state in which a guide wire is inserted into a connector when the tip of the tip pin 40 is thick and not tapered. DETAILED DESCRIPTION OF THE INVENTION

[0023] Next, an embodiment of a microcatheter inserter 100 according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of the microcatheter inserter 100 according to the embodiment. FIG. 2 is a cross-sectional view of the microcatheter inserter 100 according to the embodiment. Note that the embodiments and drawings described below exemplify a portion of the embodiment of the present invention and are not intended to limit the present invention to these configurations, and can be modified as appropriate without departing from the gist of the present invention. Note that for ease of explanation, in the claims and the specification, the "base end side" and the "tip end side" refer to the proximal side as the "base end side" and the distal end side as the "tip end side."

[0024] (First embodiment) As shown in Figures 1 to 3, the microcatheter inserter 100 according to the embodiment mainly comprises a base member 10, a guidewire fixing device 20 attached to the base member 10, a cap 30 that fixes the guidewire 90 by applying pressure to the guidewire fixing device 20 from the outside, a tip pin 40 that is disposed within the cap 30 and inserted into the insertion hole 83 of the connector 81 of the microcatheter 80, and an elastic member 50 that presses the tip pin 40.

[0025] The base member 10 is made in a hollow cylindrical shape, and the outer periphery on the base end side is formed with anti-slip irregularities (not shown) to facilitate rotation when gripped as a torquer. The outer periphery on the tip end side is threaded with a screw groove 11 so that a cap 30 can be attached. As shown in FIG. 2, the guidewire fixing device 20 is inserted into the inner periphery 12 from the tip side. Preferably, the portion where the guidewire fixing device 20 is attached is made thin enough to correspond to the thickness of the guidewire fixing device 20 so that there are no steps on the inner periphery surface, and the inner periphery is formed to have a uniform surface.

[0026] The guidewire fixing device 20 has a hollow tubular portion 21 formed on the proximal side and a pressing portion 22 formed on the distal side. The inner periphery of the pressing portion 22 has a tapered surface 25 formed in a tapered shape so that the inner diameter decreases from the tubular portion 21. The inner diameter of the guidewire passing hole 26 at the center of the pressing portion 22 is formed to be slightly larger than the diameter of the guidewire 90. The outer periphery of the pressing portion 22 is formed larger than the tubular portion 21, and the tip is divided into approximately 3 to 8 grooves 23, and by applying force from the periphery, the grooves 23 can be narrowed to constrict the guidewire passing hole 26. The width of the grooves 23 is formed narrower than the diameter of the guidewire 90 to prevent the guidewire 90 from slipping out. As shown in Figure 4, the angle a of the outer surface 22a of the tip of the pressing portion 22 relative to the central axis α is smaller than the angle b of the abutment surface 30b of the cap 30 relative to the central axis α, and by tightening the cap 30, the pressing portion 22 is pushed from the outer side toward the center, thereby tightening and fixing the guide wire 90 passing through the center.

[0027] As shown in FIG. 2 , the cap 30 has a threaded inner surface with a screw groove 31 that screws into the screw groove 11 formed in the base member 10, allowing it to be fixed to the base member 10. The inside of the cap 30 has a tapered abutment surface 30b that is angled with respect to the central axis α on the distal side, connecting to the screw groove 31. The distal end has a cylindrically shaped distal tube portion 35 on which the distal pin 40 and elastic member 50 are disposed. The distal tube portion 35 has a step 36 midway, narrowing the inner diameter on the distal end side. The cap 30 has a positioning surface 37 that makes surface contact with the end face of the connector 81 of the microcatheter 80 to be inserted, allowing the pin hole 42 to be positioned on the central axis α with the distal pin 40 at the center of the insertion hole 83 when the microcatheter inserter 100 is inserted into the insertion hole 83 of the connector 81. Similarly, the tip pin 40 should be fabricated to have an outer surface 38 that fits into the inner surface of the insertion hole 83 so that it is at the center of the insertion hole 83 and the pin hole 42 can be positioned on the central axis α.

[0028] The distal pin 40 is a component inserted into the insertion hole 83 of the connector 81 of the microcatheter 80 to guide the guidewire 90 to the vicinity of the proximal end of the microcatheter 80. The distal pin 40 is formed in a cylindrical shape with a pin hole 42. As shown in FIG. 2, the distal pin 40 is disposed so as to penetrate the distal tubular portion 35 of the cap 30 and is slidable back and forth in the longitudinal direction. The pin hole 42 is preferably designed to have an inner diameter slightly larger than the diameter of the guidewire 90 so that the inserted guidewire 90 is as straight as possible. Preferably, the hole diameter is 0.5 mm or less. The distal pin 40 has an engagement portion 41 formed in the middle of its longitudinal direction, with a diameter larger than the surrounding outer periphery, to engage with the step 36 of the distal tubular portion 35 and prevent the distal pin 40 from slipping out of the distal end of the cap 30. The distal end of the distal pin 40 is tapered so that the outer diameter gradually decreases toward the tip. The taper angle c (angle relative to the central axis) of the tip of the tip pin 40 must be smaller than the taper angle d of the insertion hole 83 of the connector 81. The insertion hole 83 of the connector 81 of the microcatheter 80 is generally formed with a taper angle of 20° or less. Therefore, it is preferable to form the taper angle to 20° or less, preferably 15° or less, and more preferably 10° or less. The diameter of the tip of the tip pin 40 should be the same as or smaller than the inner diameter of the microcatheter 80 to be inserted. If the tip diameter is too large, the tip of the guidewire 90 will bend, as shown in FIG. 7, and will not be able to pass through the connector hole. However, by making the diameter of the tip of the tip pin 40 the same as or smaller than the inner diameter of the microcatheter 80 to be inserted, it is possible to prevent the tip pin 40 from reaching only partway, and to position the tip deeper into the insertion hole 83. This allows even a guidewire 90 with a bent tip to be reliably inserted into the microcatheter, as shown in FIG. 6. Furthermore, it is preferable to round or curve the tip 48 of the inner peripheral surface of the tip pin 40. When used as a torquer, this can reduce the possibility of damaging the guide wire 90.

[0029] The elastic member 50 is disposed between the engaging portion 41 and the pressing portion 22 of the guidewire fixture 20, and biases the distal pin 40 toward the distal end. The elastic member 50 may be a spring as shown in Fig. 2, or may be made of rubber, elastomer, sponge, or the like.

[0030] The microcatheter inserter 100 fabricated as described above can be suitably used with, for example, a microcatheter 80 having a connector 81 with a tapered insertion hole 83 on the proximal side. First, the distal pin 40 of the microcatheter inserter 100 is inserted into the insertion hole 83 of the connector 81. The distal pin 40 then moves along the tapered insertion hole 83 and is naturally positioned at the center of the microcatheter 80. If the insertion hole 83 has a taper angle greater than the taper angle of the distal pin 40, the distal end of the distal pin 40 can be inserted all the way into the insertion hole 83, resulting in a highly versatile microcatheter inserter 100. When the distal pin 40 reaches the end of the insertion hole 83 and cannot be inserted any further, the spring 50 compresses, fixing the position of the distal pin 40. This allows the positioning surface 37 of the cap 30 to abut against the end face of the connector 81. This allows the pin hole 42 of the distal pin 40 to be positioned on the central axis. Furthermore, by fitting the guidewire 90 into the insertion hole 83 of the connector 81, it is positioned even more firmly, making it easier to align the pin hole 42 of the tip pin 40 with the central axis α. When the guidewire 90 is inserted from the opening at the rear end of the base member 10 in this state, it passes through the tubular portion 21 of the guidewire fixture 20 and passes through the guidewire passing holes 26 at the centers of the multiple pressing portions 22 along the tapered surfaces 25 of the pressing portions 22, with the tip of the guidewire 90 being positioned at the center of the microcatheter inserter 100. By further inserting the guidewire 90 in this state, it is inserted into the pin hole 42 at the center of the tip pin 40. By further pushing the guidewire 90, it can be easily inserted into the microcatheter 80. The guidewire 90 is then inserted to the desired position, and the insertion operation of the guidewire 90 is completed.

[0031] Next, when using the microcatheter inserter 100 as a torquer, only the microcatheter inserter 100 is pulled out a little along the guidewire 90. Then, after moving the microcatheter inserter 100 to a position suitable for use as a torquer, the cap 30 is tightened, which pushes the pressing portion 22 from the outer periphery toward the center, fixing the guidewire 90 passing through the center, and the microcatheter inserter 100 can be used as a torquer.

[0032] (Second embodiment) The microcatheter inserter 110 according to the second embodiment does not include the elastic member 50 compared to the microcatheter inserter 100 according to the first embodiment, and The coefficient of friction is different between the tip pin 40 and the tip cylindrical portion 35 of the cap 30. The other configurations are the same as those in the first embodiment, so a description thereof will be omitted.

[0033] 5, the microcatheter inserter 110 according to the second embodiment does not have an elastic member, and the coefficient of friction between the tip pin 40 and the tip tubular portion 35 of the cap 30 is large. Therefore, when the microcatheter inserter 110 is positioned vertically, it will not move due to gravity or slight shaking, and is able to hold the tip pin 40. Therefore, by inserting the tip pin 40 of the microcatheter inserter 100 into the insertion hole 83 of the connector 81, the tip pin 40 moves and is held in a predetermined position that is the shortest distance from the entrance of the catheter tube. Being able to hold the tip pin 40 in this way allows the guidewire 90 to be reinserted without incurring the load of moving the tip pin 40. [Industrial Applicability]

[0034] As shown in the above-described embodiment, it can be used as an insertion aid and torquer for a microcatheter. [Explanation of symbols]

[0035] α...center axis, 10...base member, 11...thread groove, 12...inner circumference, 20...guidewire fixing device, 21...cylindrical portion, 22...pressing portion, 22a...outer surface, 23...groove, 25...tapered surface, 26...guidewire passage hole, 30...cap, 30b...contact surface, 31...thread groove, 35...tip tubular portion, 36...step, 37...positioning surface, 40...tip pin, 41...engagement portion, 42...pin hole, 48...tip, 50...spring, 80...microcatheter, 81...connector, 83...insertion hole, 90...guidewire, 100...microcatheter inserter

Claims

1. a hollow base member having a screw groove formed on the outer periphery of the tip end thereof; a guidewire fixing device that is inserted into the hollow portion of the base member from the distal end side and has a pressing portion at the distal end that can change the inner diameter of the guidewire passage hole; a cap having a thread groove inner peripheral surface having a thread groove that screws into the thread groove of the base member, an abutment surface that contacts the thread groove inner peripheral surface, and a tip cylindrical portion that contacts the abutment surface; a tip pin disposed in the tip cylindrical portion of the cap and having a pin hole of 0.5 mm or less in the center; an elastic member that biases the tip pin toward the tip side; A microcatheter inserter comprising:

2. a hollow base member having a screw groove formed on the outer periphery of the tip end thereof; a guidewire fixing device that is inserted into the hollow portion of the base member from the distal end side and has a pressing portion at the distal end that can change the inner diameter of the guidewire passage hole; a cap having a thread groove inner peripheral surface having a thread groove that screws into the thread groove of the base member, an abutment surface that contacts the thread groove inner peripheral surface, and a tip cylindrical portion that contacts the abutment surface; a tip pin disposed in the tip cylindrical portion of the cap and having a pin hole of 0.5 mm or less in the center, A microcatheter inserter characterized in that the tip tube portion is fabricated so as to be able to hold the tip pin in a predetermined position.

3. 3. The microcatheter inserter according to claim 1, wherein the taper angle of the tip pin is smaller than the taper angle of the insertion hole of the connector.

4. The tip tube portion has a step formed in the middle, 3. The microcatheter inserter according to claim 1, wherein the tip pin has an engaging portion formed with a diameter larger than the outer periphery of the surrounding area so as to engage with the step.

5. 3. The microcatheter inserter according to claim 1, wherein the cap has a positioning surface that comes into surface contact with an end face of a connector of the microcatheter to be inserted.

6. 3. The microcatheter inserter according to claim 1, wherein the cap has an outer circumferential surface that fits with an inner circumferential surface of an insertion hole of a connector of the microcatheter to be inserted.

7. 3. The microcatheter inserter according to claim 1, wherein the taper angle of the tip pin is smaller than the taper angle of the insertion hole of the connector.

8. 3. The microcatheter inserter according to claim 1, wherein the tip of the inner peripheral surface of the tip pin is curved.

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