JPH0546419Y2 - - Google Patents

Description

[Detailed description of the invention] "Field of industrial application" This invention is used for inserting into tubular organs of the human body such as blood vessels to dilate stenotic areas, or inserting into blood vessels to stop bleeding. The present invention relates to a treatment tool for tubular organs used for.

``Prior Art'' When treating tubular organs in the human body, it may be effective to surgically expand the tubular organs. For example, treatment for atherosclerosis and the like is performed by dilating a narrowed portion of a blood vessel by surgical means. Furthermore, in treatment of destroying kidney stones with shock waves, the ureter may be dilated to remove the stones after they have been destroyed. Furthermore, it is known that the bronchi become obstructed in cases such as bronchomalacia in children, causing breathing problems, and treatment to dilate the bronchi is also performed in such cases.

Also, for example, if an artery or vein ruptures,
In cases of intracerebral hemorrhage, immediate treatment may not be possible due to the large amount of bleeding. In such cases, it is necessary to temporarily stop the blood flow before treatment, which may result in occlusion of the blood vessel.

Expanding or occluding tubular organs in this way used to be treated by extensive surgery, but recently, expansion devices made of synthetic resin, metal, etc. stent)
A method of expanding or occluding the inside of a tubular organ by inserting an occluder or an obturator is increasingly being adopted.

As an example of the above-mentioned dilation or obturator, a so-called double coil type is used, in which a metal wire such as stainless steel is formed into a coil shape to form a primary coil, and this primary coil is further formed into a coil form to form a secondary coil. are known. This coil can be inserted into a tubular organ of the human body by inserting the primary coil into a catheter or the like with the primary coil stretched out in a straight line, and pushing it out from the tip of the catheter with a pusher from behind. Then, it returns to its shape as a secondary coil within the tubular organ, expanding the narrowed part of the tubular organ or occluding the blood vessel.

However, when the diable coil-shaped expansion or treatment device is inserted into a catheter in the state of a primary coil, it attempts to return to its shape as a secondary coil within the catheter, resulting in extremely large frictional resistance when being pushed out with a pusher.

For this reason, insertion is performed by the method shown in FIG. That is, the catheter 21 is inserted into the blood vessel 31 in advance. The distal end of the catheter 21 is placed in front of the narrowed portion 32 of the blood vessel 31.
The dilator 41 stretches the secondary coil into a straight line consisting only of the primary coil and places it in a cylindrical cartridge 23, and this cartridge 23 is inserted into the catheter 21. A stopper 22 is provided on the inner periphery of the distal end of the catheter 21, and a protrusion 24 is provided on the outer periphery of the rear portion of the cartridge 23. When the cartridge 23 is inserted into the catheter 21, the protrusion 24 abuts and locks against the stopper 22. In this state, pusher 2
At step 5, the dilator 41 inside the cartridge 23 is pushed from behind, and the dilator 41 is pushed out into the constricted portion 32 in the blood vessel 31.

``Problem to be solved by the invention'' However, in the insertion method shown in FIG. 7, the cylindrical cartridge 23 has a linear shape and has a considerable length corresponding to the length of the primary coil. Therefore, it has been difficult to insert the tube into a tubular organ such as a blood vessel, which has a complicated and tortuous path. For this reason, the conventional dilator or obturator consisting of a double coil has the problem that it can only be applied to extremely limited locations.

Furthermore, when the conventional dilating or occluding device is pushed out into the blood vessel 31, the secondary coil instantly returns and expands, so the position of the dilating device 41 is fixed before the placement position can be corrected. However, there was also the problem that insertion errors were likely to occur.

Furthermore, in conventional dilation or obturator devices, when pushed out from the tip of the catheter and returned to the secondary coil, the secondary coil returns to its shape so that the axial direction of the secondary coil intersects with the axial direction of the tubular organ. For example, when inserting a dilator, there is a risk of occluding the tubular organ due to incorrect orientation of the secondary coil.

Furthermore, when inserting a conventional dilation or obturator, it is necessary to insert the tip of the catheter to the application point in the tubular organ, but if the stenosis of the tubular organ is extremely narrow, the catheter may not be able to enter. Therefore, there were cases where it was not possible to insert the card.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a treatment device for tubular organs that reduces frictional resistance when inserted through a catheter or the like and that can be easily inserted into bent tubular organs.

"Means for Solving the Problem" In order to achieve the above object, the tubular organ treatment device of the present invention consists of forming a metal wire into a coil shape to form a primary coil, and further forming this primary coil into a coil shape. a metal coil which is used as a secondary coil, a head is formed at the tip of the primary coil, and a cap having an insertion hole is attached to the rear end of the primary coil; and the cap is inserted into the primary coil of the metal coil. a core wire that is removably inserted through the hole and whose tip engages the head of the primary coil to maintain the primary coil in a straight line; A tube-shaped pusher that engages with the cap and prevents the primary coil from retreating when the core wire is extracted from the primary coil.

The present invention will be explained in more detail below.

In the present invention, a metal wire is formed into a coil shape to form a primary coil, and this primary coil is further formed into a coil form to form a secondary coil. The outer diameter of the primary coil is such that it can be inserted into a tubular organ such as a blood vessel through a catheter or the like. Further, the outer diameter of the secondary coil is set to a diameter that can effectively expand or close the inside of the tubular organ, and is determined depending on the purpose and the location of application.

The wire of this coil may be a normal metal wire such as stainless steel, but it is more preferably a wire made of a shape memory alloy such as a TiNi alloy. Further, the shape of the wire may be any of a round wire, a square wire, and a flat wire. Furthermore, the surface of the wire may be coated with resin or the like.

When making a shape memory alloy wire into a coil, it is formed into the shapes of the primary coil and secondary coil as described above, and then subjected to a restraint aging treatment at approximately 400 to 500 degrees Celsius for a predetermined time while maintaining this shape. It is possible to memorize a shape, and after being deformed at a low temperature, it can be given the property of returning to the memorized shape when the temperature exceeds the transformation point. In addition, this transformation point is preferably set at a temperature lower than body temperature, and more preferably set at 0 to 20° C. so that the structure can be fully restored when placed in a tubular organ.

This metal coil has a preferably curved head formed at the tip of the primary coil by a method such as partially melting the coil, and a synthetic resin having a core wire insertion hole at the rear end of the primary coil. It can be covered with a cap such as

Further, in the present invention, the core wire is inserted into and removed from the primary coil through the insertion hole of the cap, and the tip thereof engages with the head of the primary coil to maintain the primary coil in a straight line. A material having sufficient rigidity, preferably stainless steel wire, etc., is used.

Furthermore, as the pusher, a flexible synthetic resin tube having an inner diameter that allows the core wire to be inserted and an outer diameter that allows insertion into the catheter is preferably employed.

"Effect" When using the device for treating tubular organs of the present invention,
The metal coil is stretched, the core wire is inserted through the insertion hole of the cap attached to the rear end of the primary coil, and the tip of the core wire is engaged with the head of the tip of the primary coil. As a result, the primary coil is maintained in a linearly extended state due to the rigidity of the core wire.

Then, the metal coil and core wire are inserted into a catheter that has been inserted into a tubular organ of the human body in advance,
Furthermore, a pusher is inserted between the core wire and the catheter. The tip of the pusher engages a cap attached to the rear end of the primary coil.

After the tip of the catheter is moved to the treatment site in the tubular organ, the core wire is pushed to force the metal coil out of the tip of the catheter. Since the metal coil has a core wire inserted inside it, it cannot restore its shape to a secondary coil in that state.

After the metal coil is accurately placed in the treatment area of the tubular organ, the core wire is pulled out while pressing the rear end of the primary coil with a pusher, that is, while preventing the primary coil from retreating. It returns to the shape of the secondary coil.

In this way, in this invention, while maintaining linearity by the core wire inserted inside the primary coil,
Since the metal coil can be inserted into the catheter, the frictional resistance when the metal coil is inserted into the catheter and pushed out is extremely small, making it possible to easily insert the metal coil into the tubular organ.

In addition, since the core wire, pusher, and catheter all have flexibility or elasticity, they can be easily inserted into curved parts of tubular organs, and the range of applications can be expanded.

Furthermore, even if the metal coil is pushed out of the catheter, it does not return to its shape as a secondary coil while the core wire is inserted, so the metal coil can be accurately placed at the target treatment site.

Furthermore, when the metal coil is extruded from the catheter, the directionality of the metal coil is determined by the core wire, so that the secondary coil returns to its shape so that its axial direction intersects with the axial direction of the tubular organ. is also prevented.

Furthermore, even if the narrowed part of a tubular organ is too narrow to insert the tip of the catheter, the metal coil can be pushed out from the tip of the catheter and inserted into the narrowed part while being maintained in a straight line by the core wire.

Embodiment FIGS. 1 to 6 show an embodiment of the device for treating tubular organs according to the present invention. Note that in this example,
Although this is an example in which the present invention is applied to a blood vessel dilator, the present invention can also be applied to other tubular organ dilators, blood vessel occlusion devices, etc. with a similar structure.

In FIG. 1, 21 represents a catheter, and 31 represents a blood vessel.

As shown in FIG. 2, the metal coil 11 is a so-called double coil in which a wire 13 made of a shape memory alloy is formed into a primary coil 12a, and this primary coil 12a is further formed into a secondary coil 12b. The diameter of the primary coil 12a is the same as that of the catheter 2.
The diameter is such that it can be easily inserted into the secondary coil 1.
The diameter of 2b is set to be a diameter that can effectively expand the occluded portion of the blood vessel 31. The metal coil 11 has been subjected to shape memory treatment in the above-mentioned double coil shape, and has a transformation point of 0 to 20°C.

The tip of the primary coil 12a is formed into a hemispherical head 14 by melting a metal wire 13. However, the head 14 can also be formed by covering the tip of the primary coil 12a with a suitable cap or the like. Furthermore, a synthetic resin cap 15 is attached to the rear end of the primary coil 12a.
5 is formed with an insertion hole 16 for a core wire 17, which will be described later. As shown in FIG. 3, this cap 15 may be attached by placing a cap made of heat-shrinkable resin, shape-memory resin, etc. over the rear end of the primary coil 12a and heat-shrinking it. Alternatively, as shown in FIG. 4, the primary coil 12a may be formed by dipping the rear end portion of the primary coil 12a in a resin liquid and then solidifying the resin liquid.

In the present invention, the metal coil 11 is placed in a state where the primary coil 12a extends linearly, and the core wire 17 made of stainless steel is inserted through the insertion hole 16 of the cap 15. The core wire 17 may be of various shapes, such as a round wire or a square wire, but it is preferably a round wire that loosely fits or fits into the inner diameter of the primary coil 12a. The core wire 17 is the primary coil 12a.
Its tip engages the head 14 through the inside. The core wire 17 prevents the metal coil 11 from returning to its double coil shape due to its rigidity, and maintains the primary coil 12a in a substantially linearly extended state. In this state, as shown in FIG.
It can be inserted into the inside of the catheter 21 inserted inside.

Moreover, between the core wire 17 and the catheter 21,
A pusher 18 consisting of a tube made of synthetic resin is inserted. The pusher 18 has an inner diameter that allows the core wire 17 to be inserted therein, and an outer diameter that allows the pusher 18 to be inserted into the catheter 21. Also, Pushya 1
The tip of the metal coil 8 is adapted to engage with a cap 15 attached to the rear end of the metal coil 11.

Next, how to use this treatment tool will be explained.

As shown in FIG. 1, first, a catheter 21 is inserted into a blood vessel 31 by a known method, and a metal coil 11 having a core wire 17 inserted therein and maintained in a straight shape is inserted into this catheter 21. The core wire 17 is
It is pulled out from the proximal end of the catheter 21 and can be operated by an operator by holding the proximal end with his or her hand. Further, a tube-shaped pusher 15 is attached to the outer periphery of the core wire 17, and the pusher 15 is inserted between the core wire 17 and the catheter 21.

As shown in FIG. 5, after inserting the tip of the catheter 21 to the front of the narrowed part 31a of the blood vessel 31,
The core wire 17 is inserted without moving the catheter 21.
is pushed in, and the metal coil 11 held at the tip of the core wire 17 is inserted into the narrowed portion 31a. At this time, the tip of the core wire 17 is engaged with the head 14 of the metal coil 11. Further, the metal coil 11 is connected to the blood vessel 3.
1, the temperature rises, and the core wire 17 attempts to return to its shape, but the core wire 17 prevents it from returning to its shape.

Once the metal coil 11 is placed in the proper position,
Abut the tip of the pusher 15 against the cap 15 of the metal coil 11, and while pressing the metal coil 11 with the pusher 15 so that it does not move back, insert the core wire 1.
7 is pulled out from inside the metal coil 11.

As shown in FIG. 6, when the core wire 17 is pulled out, the metal coil 11 returns to the shape of the secondary coil and expands in diameter, thereby expanding the narrowed portion 31a of the blood vessel 31. After the insertion of the metal coil 11 is completed, the core wire 17 and pusher 18 are inserted into the catheter 2.
1, and then insert the catheter 21 into the blood vessel 31.
Pull it out from within.

As described above, since the metal coil 11 is held in a straight state by the core wire 17, the frictional resistance is reduced, making it easy to insert into the catheter 21 and push out from the tip of the catheter 21.

Furthermore, since the core wire 17, pusher 18, and catheter 21 all have a certain degree of flexibility, they can be easily inserted into curved portions such as the blood vessel 31.

Furthermore, when extruding the metal coil 11, the core wire 17 inserted into the inside of the coil 11 prevents the shape from returning to a double coil, and the directionality can be determined correctly, so the metal coil 11 is extruded in this state. By placing the core wire 17 in an appropriate position and pulling out the core wire 17, the shape can be restored to the correct state.

When the present invention is applied to a blood vessel occluder, Dacron fibers or the like may be entangled between the pitches of the metal coil 11 to further improve the hemostasis effect. In addition, when applied to an obturator, the shape of the secondary coil when it returns to its shape may be such that the coil diameter gradually decreases to form a tapered shape as a whole, or a randomly bent shape. You may do as you like. In the case of an obturator, the diameter of the primary coil is preferably 1 mm or less, and the diameter of the secondary coil is preferably about 3 to 8 mm.

"Effects of the Invention" As explained above, according to the device for treating tubular organs of the present invention, the core wire is inserted into the metal coil to maintain linearity, so that it can be easily inserted into the catheter and from the tip of the catheter. can be easily extruded. Moreover, when the metal coil is extruded into the tubular organ, the core wire can be pulled out after the metal coil is placed in an accurate position and the shape can be restored. At this time, since the directionality of the metal coil is accurately determined by the core wire, the direction of the coil when it returns to its shape can be ensured. Furthermore, by pushing the core wire, the metal coil can be pushed out of the catheter and inserted into the narrowed area, so it can be inserted into narrow areas where the tip of the catheter cannot fit.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a tubular organ treatment device according to an embodiment of the present invention inserted into a catheter;
FIG. 2 is a perspective view showing a state in which the metal coil in the treatment device has returned to its shape, FIG. 3 is a partial sectional view showing an example of the state in which the cap is attached to the treatment device, and FIG. 4 is a perspective view of the cap in the treatment device. A partial cross-sectional view showing another example of the installed state, FIG. 5 is a cross-sectional view showing a state in which the metal coil of the treatment device is held by the core wire and pushed out from the catheter, and FIG. 6 is a partial cross-sectional view showing the metal coil of the treatment device held by the core wire and pushed out from the catheter. FIG. 7 is a cross-sectional view showing a state in which the blood vessel has been extracted and restored to its shape, and FIG. 7 is a diagram showing a method of dilating a narrowed portion of a blood vessel using a conventional dilator. In the figure, 11 is a metal coil, 12a is a primary coil, 12b is a secondary coil, 13 is a wire, 14 is a head, 15 is a cap, 16 is an insertion hole, 17 is a core wire, 18 is a pusher, 21 is a catheter, 31
are blood vessels.

Claims (1)

[Claims for Utility Model Registration] (1) A primary coil is formed by forming a metal wire into a coil, this primary coil is further formed into a coil to form a secondary coil, and a head is attached to the tip of the primary coil. a metal coil having a cap formed thereon and having an insertion hole attached to the rear end of the primary coil; the metal coil being removably inserted into the primary coil of the metal coil through the insertion hole of the cap;
a core wire whose distal end engages with the head of the primary coil to maintain the primary coil in a straight line; and a core wire disposed around the outer periphery of the core wire, whose distal end engages with the cap attached to the primary coil; 1. A treatment tool for a tubular organ, comprising: a tube-shaped pusher that prevents the primary coil from retreating when the core wire is extracted from the primary coil. (2) The device for treating tubular organs according to claim 1, wherein the metal coil is made of a shape memory alloy having a transformation point lower than body temperature.