JPH01119266A - Appliance for securing cavity bore - Google Patents

Abstract

PURPOSE:To smoothly leave a bore securing appliance in a target site, by providing a catheter sheath which can hold a catheter with the bore securing appliance in the cavity thereof. CONSTITUTION:A bore securing system 1 includes a bore securing appliance, i.e., a stent, 10, a catheter 20 and a catheter sheath 30. The stent 10 consists of a two-directional flat shape-memory alloy wire spirally wound. The catheter 20 includes a catheter tube 21 and a hollow hub 22, and the catheter sheath 30 includes a sheath tube 31 and a hollow sheath hub 32. The catheter sheath 30 can hold the catheter 20 with the stent 10 in the lumen thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a system for securing the inner diameter of a body cavity in which an instrument for securing the inner diameter is placed in or retrieved from the inner lumen of a tubular organ such as a blood vessel, digestive tract, or trachea.

[Prior Art] Conventionally, for example, after dilating and indwelling a narrowed part of a coronary artery with a vasodilator catheter, the inner diameter of the inner lumen of a tubular organ is secured to prevent re-narrowing of the narrowed part of the coronary artery. Securing equipment (
Stents) have been proposed.

As a conventional inner diameter securing device, the one described in Japanese Patent Publication No. 111-8855 uses a unidirectional shape memory alloy made of a Ti-Ni alloy, which is shaped into a tubular shape having an inner diameter approximately equal to the normal blood vessel inner diameter. to memorize this shape,
In order to further facilitate insertion into the blood vessel, the outer diameter is deformed to a smaller size, and after introduction into the desired position of the blood vessel, it is heated with hot water or the like to expand and restore the memorized shape before use.

[Problems to be Solved by the Invention] By the way, the work of indwelling the above-mentioned conventional inner diameter securing device made of a unidirectional shape memory alloy at a target site of a blood vessel is as follows:
Normally, a guiding catheter is first placed in a blood vessel, and then an inner diameter securing device is passed through the guiding catheter and advanced to the target site. However, in the above case, since the inner diameter securing device is advanced through the narrow guiding catheter while being exposed, there are problems such as the inner diameter securing device getting caught or deformed midway through the guiding catheter. Furthermore, since the guiding catheter for boat fishing is too rigid to pass through the bend at the distal end of the blood vessel, if the target area is beyond the bend, the inner diameter securing device is attached to the catheter along with the vessel. Because the device is passed through the inside of the device exposed, there are problems with the inner diameter securing device getting caught or deformed on the way.
Or store the inner diameter securing device in the radial direction! In order to maintain
There were problems such as the need to inject a large amount of cooling water.

In addition, the present inventors have already proposed an inner diameter securing device made of a bidirectional shape memory alloy, that is, a device that reversibly develops two memory shapes on a high temperature side and a low temperature side at a certain transformation temperature. The shape memory alloy has the property of expanding radially at or near body temperature to secure the inner diameter of blood vessels, etc., and contracting radially at or below body temperature to move inside blood vessels, etc. This internal diameter securing device is revolutionary as an internal diameter securing device that can be repositioned and retrieved. However, with this device for securing the inner diameter, since the device for securing the inner diameter is advanced while being passed through the narrow guiding catheter, there is a problem that the device for securing the inner diameter gets caught or deforms on the way. Furthermore, with this inner diameter securing device, when advancing the inner diameter securing device while passing it through the guiding catheter, a large amount of cooling water must be injected in order to maintain the inner diameter securing device in the radial direction. In addition, as with unidirectional shape memory alloys, the guiding catheter has high rigidity and cannot pass through the bend at the distal end of the blood vessel, so if the target area is beyond the bend, the inner diameter must be secured. Because the device and the attached catheter are passed through the blood vessel exposed, there are problems with the inner diameter securing device getting caught or deforming midway through, or requiring a large amount of cooling water to maintain the inner diameter securing device contracted in the radial direction. There were problems such as having to inject.

An object of the present invention is to enable smooth and easy movement of an inner diameter securing device within a tubular vessel.

[Means for Solving the Problems] A first aspect of the present invention is to use an inner diameter securing device formed into a substantially cylindrical body made of a shape memory alloy whose dimensions can change in the radial direction as the temperature changes. A device for securing the inner diameter of a body cavity to be indwelled in the body, the catheter having the inner diameter securing device attached to the outer circumferential surface of the inner diameter securing device mounting portion near the distal end;
The catheter sheath is open at both ends and has a lumen in which the catheter equipped with the inner diameter securing device can be housed.

The second aspect of the present invention is to retain or retrieve an inner diameter securing device in a body cavity, which is formed into a substantially cylindrical shape made of a bidirectional shape memory alloy that can change dimensions in the radial direction with temperature changes. The apparatus for securing the inner diameter of a body cavity includes a catheter to which the inner diameter securing device can be attached to the outer circumferential surface of the inner diameter securing device attachment part near the distal end, and a catheter having both ends open and having the contracted catheter attached to the inner diameter of the body cavity. The catheter sheath can house the catheter equipped with the inner diameter securing device and has an inner diameter equal to or smaller than the outer diameter of the expanded inner diameter securing device.

[Function] (System in which the inner diameter securing device is made of a unidirectional shape memory alloy) In the present invention, when the inner diameter securing device is made of a unidirectional shape memory alloy, the inner diameter of the tubular organ to be indwelled near body temperature is A substantially cylindrical inner diameter securing device, such as a coil or mesh shape, is used, which has an outer diameter equal to or slightly larger than the diameter of the tube.

At temperatures substantially lower than body temperature (below the transformation temperature), the inner diameter securing device can be freely deformed, so it is attached by wrapping around the inner diameter securing device mounting section near the catheter tip/end and stored within the catheter sheath. be done. In this way, by introducing the combination of the inner diameter securing device attached to the catheter and housed within the catheter sheath into the tubular organ, the inner diameter securing device can be easily indwelled at the target site.

That is, by passing a guide wire through the tubular organ in which the inner diameter securing instrument is to be placed using a common technique and introducing the above combination along the guide wire, the inner diameter securing instrument can be easily introduced into the target site. At this time, according to the present invention, due to the presence of the catheter sheath, the inner diameter securing device is not exposed to the tubular organ, and there is no risk of it getting caught or deformed on the way, and the catheter sheath has flexibility. This makes it possible to easily pass through vascular bends together with the inner diameter securing device and catheter.

The inner diameter securing device introduced into the target area as described above is
After being inserted into the catheter and ejected from the catheter sheath, the catheter is heated by body temperature to expand its diameter and placed in the target site of the tubular organ.

Note that cooling water can be supplied from the catheter sheath when the inner diameter ensuring device made of the unidirectional shape memory alloy is introduced, and hot water can also be supplied from the catheter sheath when the device is indwelled. Further, in a preferred embodiment of the present invention, the catheter is provided with a passageway extending from the proximal end to at least the vicinity of the distal end, and a communication port through which the wave passage is communicated with the outer surface of the inner diameter securing device attachment part near the distal end. The cooling water and hot water can be supplied from the communication port.

Here, the unidirectional shape memory alloy refers to an alloy that undergoes thermoelastic martensitic transformation and changes to the pre-memorized shape of the matrix when the temperature exceeds the reverse transformation start temperature, and freely changes below the transformation temperature. A material that can be deformed, and once it reaches a temperature higher than the reverse transformation start temperature and restores its memorized shape, it maintains its memorized shape even if the temperature drops below its transformation temperature, unless external force is applied.

(System in which the inner diameter securing device is made of a bidirectional shape memory alloy) In the present invention, when the inner diameter securing device is made of a bidirectional shape memory alloy, the tubular organ should be indwelled at a temperature substantially lower than 1 body temperature. A substantially cylindrical inner diameter securing device, such as a coil or mesh type, is used, which has an outer diameter smaller than the inner cavity of the tube. In addition, the inner diameter securing device made of this bidirectional shape memory alloy expands at or near body temperature and stores an outer diameter that is equal to or slightly larger than the inner diameter of the tubular organ to be indwelled. The inner diameter securing device is housed in the catheter sheath while attached to the catheter, and by introducing this combination into the tubular organ, the inner diameter securing device can be easily placed at the target site and retrieved.

That is, by passing a guide wire through the tubular organ in which the inner diameter securing device is to be placed using a common technique and introducing the above combination along the guide wire, the inner diameter securing device can be easily introduced to the target site. At this time, according to the present invention, due to the presence of the catheter sheath, the inner diameter securing device is reliably held within the sheath while being attached to the catheter.
There is no need to supply a large amount of cooling water to maintain the diameter reduction so that the catheter is wrapped around the catheter without any gaps, and the burden on the patient can be reduced. In addition, due to the presence of a catheter sheath,
The inner diameter securing device is not exposed to the tubular organ, and there is no risk of it getting caught or deformed on the way, and
Since the catheter sheath is flexible, it can easily pass through a vascular bend together with the inner diameter securing device and the catheter.

The inner diameter securing device introduced into the target area as described above is
Cooling water is supplied from the catheter sheath and the catheter is wrapped around the catheter. After being pushed out of the catheter sheath, the cooling water is stopped, the catheter is heated by body temperature, expands, and is placed at the target site in the tubular organ. .

Furthermore, in order to retrieve the inner diameter securing device indwelled at the target site as described above, the guide wire is passed through the indwelling portion of the inner diameter securing device, and the combination of the catheter and catheter sheath is introduced along this into the indwelling portion. do. After that, the distal end of the catheter is protruded from the catheter sheath, and cooling water is supplied from the catheter sheath to reduce the diameter of the inner diameter securing device, and the inner diameter securing device is wrapped around the attachment portion of the catheter. It can also be pulled into the catheter sheath and recovered. In this case as well, only a small amount of cooling water is required, and after the inner diameter securing device is roughly drawn into the catheter sheath, the inner diameter securing device can be reliably recovered without the risk of getting caught or deformed.

In a preferred embodiment of the present invention, the catheter is provided with a wave path extending from the proximal end to at least the vicinity of the distal end, and a communication port through which the flow path is communicated with the outer surface of the inner diameter securing device mounting portion near the distal end, and the above-mentioned When introducing the inner diameter ensuring device made of a bidirectional shape memory alloy, the cooling water to be supplied during recovery can be supplied from the communication port.

Here, a bidirectional shape memory alloy is one that has a shape memorized in advance on both the high temperature side and the low temperature side with a certain transformation temperature as the boundary, and can reversibly develop this shape by changing the temperature.

Note that the shape memory alloy used in the practice of the present invention is, for example, a Ti-X1 alloy (composition: 50 to 53 atomic % Ni, preferably 50 to 51 atomic % Ni, transformation temperature: A
f30-45°C, M'flO~30''0) are preferred.

[Example] Fig. 1 is a sectional view showing an inner diameter securing system according to a first embodiment of the present invention, Figs. 2 (A) and (B) are side views showing an inner diameter securing device, and Fig. 3 is a catheter. 4 is a side view showing the catheter sheath, and FIGS. 5(A) to (E) are side views showing the catheter sheath.
) is a schematic diagram showing the process of introducing and placing the inner diameter securing device.

The inner diameter securing system l is an inner diameter securing device! (Stent) 1
0. It is composed of a combination of a catheter 20 and a catheter sheath 30.

The stent 10 is made of a flat bidirectional shape memory alloy filament (for example, Xl-Ti) as shown in FIGS.
The molded material is formed into a substantially cylindrical spiral shape. The stent 10 maintains a radially expanded shape as shown in FIG.
5 to 25° C.), it maintains a radially reduced shape as shown in FIG. 2(A).

The stent used in this example (Ti-Ni bidirectional shape memory alloy, about 51 atomic % Ni, wall thickness 0.03℃, width 1mm) had a φ1.6 layer at 20℃ or below, and a φ1.6 layer at 32℃.
As a result, a diameter change of φ2.8 mm occurred.

The diameter, length, etc. of the stent 10 are appropriately selected depending on the inner diameter and length of the intended indwelling portion of the tubular organ. That is, the diameter of the stent IO can be made to match the inner diameter of a tubular organ such as a blood vessel in which it is to be indwelled when it is expanded, and can be made thin enough to be introduced into the indwelling part when it is contracted.

Here, the shape of the stent is not limited to the above-mentioned spiral shape, but may be substantially cylindrical, for example, a mesh shape, a spiral shape, or the like.

Furthermore, it is desirable that the stent 10 includes an X-ray opaque marker 11 on at least a portion of the cylindrical body.

The catheter 20 includes a catheter tube 21 (made of thermoplastic resin such as polyethylene, EVA, PVC, etc.) that is open at both ends, and a tube extending from the proximal end of the catheter tube 21 to the distal end thereof. The catheter 20 includes a hollow hub portion 22 (made of polycarbonate, polypropylene, etc.) that is provided in communication with a lumen extending up to The stent 10 can be attached to the outer peripheral surface of the portion 23.

The catheter 20 also has a flow path 24 formed between the lumen of the catheter tube 21 and the inner lumen of the hub portion 20, and a large number of side hole-shaped communication ports 25 that communicate the flow path 24 with the outer surface of the catheter tube 21. The stent cooling fluid supplied to the flow path 24 can be discharged radially from the communication port 25 .

Note that the communication port E may be in the form of a slit.

Further, the catheter 20 has a stent attachment portion 23 on the proximal end side of the stent attachment portion 23, which is provided with the communication port 25.
It is preferable that the stent 10 is provided with a bulging portion 26 having an outer diameter larger than the outer diameter of the stent 10 attached to the catheter sheath 30. When you pull inside,
This is to prevent the catheter sheath 30 from getting caught on the tip of the catheter sheath 30. Note that the bulging portion may be provided at both the proximal end side and the distal end side of the stent attachment portion 23.

Further, the catheter 20 is preferably equipped with an X-ray opaque marker 27 (for example, made of gold, platinum, etc.) near the tip of the catheter tube 21, so that the position of the catheter 20 can be confirmed under X-ray fluoroscopy. Also, the positional relationship between the stent 10 and the sheath 30 can be confirmed.

As shown in FIG. 3, the hub portion 22 of the catheter 20 includes a straight cylindrical portion 22A and a branch portion 22B branching from the intermediate portion.
It consists of The straight cylindrical portion 22A serves as an introduction port for the guide wire, and therefore a check valve 28 (for example, made of a flexible material such as silicone rubber) for preventing leakage of blood etc. is provided near the proximal opening of the straight cylindrical portion 22A. It is set in.

Note that the branch portion 22B is used for introducing cooling liquid and the like, and has a three-way stopcock 29.

The catheter sheath 30 includes a sheath tube 21 (made of, for example, PVC, polyethylene, or fluororesin) that is open at both ends, and a rear end of the sheath tube 31 that is connected to the lumen of the sheath tube 31. The catheter sheath 30 is comprised of a hollow sheath hub portion 32 (made of, for example, polypropylene, polycarbonate, etc.) and can accommodate the catheter 20 equipped with the stent IO in its lumen.

It is desirable that the material of the sheath tube 31 of the catheter sheath 30 contains an X-ray contrast agent so that its position can be confirmed under X-ray fluoroscopy, or that the catheter sheath 30 is formed near the distal end of the sheath tube 31. It may also include at least one radiopaque marker.

It is desirable that the inner diameter of the sheath tube 31 of the catheter sheath 30 is smaller than the diameter when the stent 10 is expanded. This is because the stent 10 tends to expand beyond the inner diameter of the sheath 30, so the stent 10 is fixed inside the sheath 30. This eliminates the need to run cooling water and wrap the stent 10 around the catheter 20 when introducing the combination of the stent 10, the catheter 20, and the sheath 30 up to the front of the indwelling part, making it possible to introduce the stent 10 reliably. Furthermore, this allows the amount of cooling water to be injected to be reduced, greatly reducing the burden on the patient.

The sheath hub portion 32 of the catheter sheath 30, through which the catheter 20 enters, is provided with a reverse +h valve 33 to prevent leakage of blood or the like. Further, the sheath hub portion 32 is provided with a sheath port 34 for injecting a contrast agent or the like.

Next, the operation of the above embodiment will be explained.

In the above-mentioned system for securing the inner diameter, the stent 10 is made of a bidirectional shape memory alloy.
0 remembers an outer diameter smaller than the inner lumen of the tubular organ to be placed at a temperature substantially below body temperature. Moreover, this stent 10 expands at or near body temperature and has an outer diameter that is equal to or slightly larger than the inner diameter of the tubular organ to be indwelled. This stent IO is housed inside the catheter sheath 30 while being attached to the catheter 20, and by introducing this combination into a tubular organ, the stent 10 can be easily placed in a target site and retrieved.

That is, the stent 10 can be easily introduced into the target site by passing a guide wire through the tubular organ in which the stent 10 is to be indwelled, using a simple technique, and introducing the above-mentioned combination along the guide wire. (See Figure 5(A)).

At this time, according to the present invention, due to the presence of the catheter sheath 30, the stencil 10 is securely held inside the sheath 30 while being attached to the catheter 20, so that the diameter can be reduced so as to wrap it around the catheter 20 without any gaps. There is no need to supply a large amount of cooling water for maintenance, reducing the burden on the patient. Further, due to the presence of the catheter sheath 30, the stent 10 is not exposed to the tubular organ, and there is no risk of the stent being caught or deformed on the way.

The stent 10 introduced into the target site as described above is
Cooling water is supplied from the catheter sheath 30 and/or the communication port 25 of the catheter 20 and the catheter 20 is wound around the catheter 20 (see FIG. 5(B)), and after being ejected from the catheter sheath 30 (see FIG. 5(C) (see FIG. 5(D)), and by stopping the cooling water, it is warmed by body temperature and expands (see FIG. 5(D)), and is placed in the target site of the tubular organ (see FIG. 5(E)).

Furthermore, the stent 1 placed in the target site as described above
For retrieval, the guide wire is passed through the indwelling part of the stent 10, and the combination of the catheter 20 and catheter sheath 30 is introduced along this into the indwelling part. after that,
The distal end of the catheter 20 is protruded from the catheter sheath 30 and cooling water is supplied from the catheter sheath 30 and/or the communication port 25 of the catheter 20 to reduce the diameter of the stent 10 and wrap it around the stent attachment part 23 of the catheter 20. The stent 10 can be pulled into the catheter sheath 30 together with the catheter 20 and recovered. In this case as well, a small amount of cooling water is sufficient, and furthermore, after the stent 10 is drawn into the catheter sheath 30, there is no risk of the stent 10 being caught or deformed, and the stent 10 can be reliably recovered.

In carrying out the present invention, when the inner diameter securing device is made of a unidirectional shape memory alloy, a coiled shape having an outer diameter equal to or slightly larger than the inner diameter of the tubular organ to be indwelled near body temperature may be used. Alternatively, a substantially cylindrical inner diameter securing device such as a mesh-like device is used.

Since the inner diameter securing device can be freely deformed at temperatures substantially lower than body temperature (below the transformation temperature), it is attached so as to wrap around the inner diameter securing device mounting portion near the catheter tip and stored within the catheter sheath. . In this way, by introducing the combination of the inner diameter securing device attached to the catheter and housed within the catheter sheath into the tubular organ, the inner diameter securing device can be easily indwelled at the target site.

That is, by passing a guide wire through the tubular organ in which the inner diameter securing instrument is to be placed using a common technique and introducing the above combination along the guide wire, the inner diameter securing instrument can be easily introduced into the target site. At this time, according to the present invention, due to the presence of the catheter sheath, the inner diameter securing device is not exposed to the tubular organ, and there is no risk of it getting caught or deformed on the way.

The inner diameter securing device introduced into the target area as described above is
After being inserted into the catheter and ejected from the catheter sheath, the catheter is heated by body temperature to expand its diameter and placed in the target site of the tubular organ.

Note that cooling water can be supplied from the catheter sheath when the inner diameter ensuring device made of the unidirectional shape memory alloy is introduced, and hot water can also be supplied from the catheter sheath when the device is indwelled. Further, in a preferred embodiment of the present invention, the catheter is provided with a flow path extending from the proximal end to at least the vicinity of the distal end, and a communication port that communicates the flow path with the outer surface of the inner diameter securing device mounting portion near the distal end, Cooling water and hot water described in 1 can be supplied from this communication port.

Hereinafter, specific implementation results of the present invention will be explained.

(Example 1) A stent made of a bidirectional shape memory alloy was placed and retrieved using the following instrument.

The material of the stent is Ti-Ni (approximately 51 atomic% Ni)
The shape of the stent has a wall thickness t = 0.03 mm,
A material with a width W of 1 μl was formed into a spiral shape as shown in FIG. The stent has a diameter of 1.8 mm below 20°C and a diameter of 1.8 mm above 32°C.
The diameter changes to 2.8■■. Gold markers on both ends of the stent (thickness t = 0.02+*m, w = 1.0m+*
) Two pieces were fixed.

The material of the catheter was a polyethylene-EVA blend. The shape of the catheter was as shown in FIG.

The material of the catheter sheath was PVC containing [1i20z]. The shape of the sheath was as shown in FIG.

The stent was placed and retrieved using the following procedure.

■ A mongrel (17 kg) was given a pre-operative mound and aspirin (8 kg) on the day of surgery.
0 mg) dipyridamale (50 mg) orally.

■ Under general anesthesia, place the introducer in the femoral artery using the standard method and then heparinize it (200 U/kg). ■ Introduce the replacement guide wire into the target blood vessel using the standard method. In this case, the forceful carotid artery was selected.

■Introduce the set combination of stent, catheter, and sheath (see Figure 1) along the guide wire until just before the indwelling position.

■Cooling port (water-cooled saline) from the catheter side hole (communication port)
The stent is contracted by flushing at 30 min.

■Push the catheter out of the sheath, advance the stent to the indwelling position, turn off the cooling water, expand the stent, leave it in place, and remove the catheter and sheath.

After 0.30 minutes, the set of catheter and sheath is advanced along the guide wire to the front of the stent indwelling site, and then only the catheter is advanced to the indwelling site and cooling water is poured.

■After confirming that the stent is wrapped around the catheter, pull the catheter and stent into the sheath, fill the IF with cooling water, and remove the sheath to complete recovery.

Note that ■ to ■ were performed under X-ray fluoroscopy.

It has been found that the above procedure allows for easy placement and retrieval of the stent.

(Example 2) For a unidirectional shape memory alloy stent, the following devices,
Indwelling was easily performed by following the procedure.

The stent was formed with the same dimensions and composition as in Example 1, and
The shape of φ2.8 m was memorized at 2° C. or higher.

The same catheter and catheter sheath as in Example 1 were used.

(2) A guidewire is placed in the carotid artery of a mongrel dog in the same manner as in Example 1, and the stent is wrapped around a catheter and a sheath is introduced along the guidewire to the indwelling site.

■Push out the catheter and stent at the indwelling site and inject physiological saline warmed to 45°C through the catheter side hole. This allowed the stent to expand and deploy.

[Effects of the Invention 1] As described above, the first aspect of the present invention is to use an inner diameter securing device formed into a substantially cylindrical body made of a shape memory alloy whose dimensions can change in the radial direction in accordance with temperature changes in a body cavity. A device for securing the inner diameter of a body cavity for indwelling in the body, the catheter having an inner diameter securing device attached to the outer peripheral surface of an inner diameter securing device mounting portion near the distal end, and a catheter having both ends open and inserted into the inner lumen. It consists of a catheter sheath capable of housing the catheter described in 1 above, which is equipped with the inner diameter securing device. Therefore, when the device for securing the inner diameter is indwelled at the target site of the tubular organ, the presence of the catheter sheath prevents the device for securing the inner diameter from being exposed to the tubular organ, and there is no risk of the device getting caught or deformed on the way.

In addition, the second aspect of the present invention is to indwell an inner diameter securing device in a body cavity, which is formed into a substantially cylindrical shape made of a bidirectional shape memory alloy that can change dimensions in the radial direction with temperature changes, or A device for securing the inner diameter of a body cavity for recovery, which includes a catheter to which the inner diameter securing device can be attached to the outer circumferential surface of the inner diameter securing device attachment part near the distal end, and a catheter whose both ends are open and into which the inner diameter is contracted. The catheter sheath is capable of housing the catheter equipped with the inner diameter securing device and has an inner diameter equal to or smaller than the outer diameter of the expanded inner diameter securing device. Therefore, when placing and retrieving the device for securing the inner diameter at the target site of the tubular organ, the presence of the catheter sheath ensures that the device for securing the inner diameter is securely held within the sheath while attached to the catheter. There is no need to supply a large amount of cooling water to maintain the diameter reduction so that it wraps around without any gaps.
The burden on patients can be reduced. Also.

Due to the presence of the catheter sheath, the inner diameter securing device is not exposed to the tubular organ, and there is no risk of it becoming caught or deformed on the way.

Therefore, according to the first and second aspects of the present invention, the inner diameter securing device can be moved smoothly and easily within the tubular organ.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an inner diameter securing system according to a first embodiment of the present invention, FIGS. 2(A) and (B) are side views showing an inner diameter securing device, and FIG. 3 is a side view showing a catheter. , FIG. 4 is a side view showing the catheter sheath, and FIGS. 5(A) to (E)
) is a schematic diagram showing the introduction and retention process of the inner diameter securing device. l...Inner diameter securing system. 10... Inner diameter securing device (stent). DESCRIPTION OF SYMBOLS 11... Radio-opaque marker, 20... Catheter, 21... Catheter tube, 22... Hub part, 23... Stent attachment part, 24... Channel. 25...Communication port, 26...Bulging portion, 27...X-ray opaque marker, 28...Check valve, 30...Catheter sheath. 31...Sheath tube. 32...Sheath hub part, 33...Check valve.

Claims (17)

[Claims] (1) A device for securing the inner diameter of a body cavity for indwelling in the body cavity an inner diameter securing instrument formed into a substantially cylindrical body made of a shape memory alloy whose dimensions can change in the radial direction with temperature changes. a catheter to which the inner diameter securing device can be attached to the outer circumferential surface of an inner diameter securing device mounting portion near the distal end; and a catheter whose both ends are open and the catheter having the inner diameter securing device attached thereto can be housed in the lumen thereof. A device for securing the inner diameter of a body cavity consisting of a sheath. (2) The catheter has a flow path extending from the proximal end to at least the vicinity of the distal end, and a side hole or slit-shaped communication port that communicates the flow path with the outer surface of the catheter is attached to an inner diameter securing device near the distal end. An apparatus for securing an inner diameter of a body cavity according to claim 1, which is provided in a body cavity. (3) In the catheter, both the outer diameters of the proximal end side and the distal end side of the inner diameter securing device mounting portion near the distal end or the outer diameter of the proximal end side are the inner diameter of the inner diameter securing device mounting portion. The device for securing the inner diameter of a body cavity according to claim 1 or 2, which has an outer diameter greater than the outer diameter of the securing instrument. (4) The catheter includes a catheter lumen extending from the proximal end to at least the vicinity of the proximal end, and a hollow hub portion provided at the proximal end so as to communicate with the catheter lumen; 4. The device for securing an inner diameter of a body cavity according to claim 2 or 3, wherein the flow path is formed by the inner lumen of the catheter and the inner lumen of the hub portion. (5) The device for securing the inner diameter of a body cavity according to claim 4, wherein the hub portion is composed of a branch hub having two ports, one of which is provided with a check valve. (6) The device for securing the inner diameter of a body cavity according to any one of claims 1 to 5, wherein the catheter is provided with at least one radiopaque marker near the distal end. (7) Claims 1 to 6, wherein the catheter sheath contains an X-ray opaque substance in its material or has at least one X-ray opaque marker near its tip. The device for securing the inner diameter of a body cavity according to any one of the above. (8) The catheter sheath includes a sheath lumen extending between both ends, and a hollow hub portion provided at the proximal end so as to communicate with the sheath lumen, and a check valve in the hub portion. The device for securing the inner diameter of a body cavity according to any one of claims 1 to 7, wherein the device is provided with: (9) A body cavity for indwelling or retrieving an inner diameter securing device formed into a substantially cylindrical shape made of a bidirectional shape memory alloy that can change its dimensions in the radial direction with temperature changes. The device for securing an inner diameter includes a catheter to which the inner diameter securing device can be attached to the outer circumferential surface of an inner diameter securing device mounting portion near the distal end, and a catheter having both ends open and the contracted inner diameter securing device attached to the inner lumen. A device for securing the inner diameter of a body cavity, which comprises a catheter sheath which can accommodate the above-mentioned catheter and which has an inner diameter equal to or smaller than the outer diameter of the expanded inner diameter securing device. (10) The catheter is provided with a flow path extending from the proximal end to at least the vicinity of the distal end, and a side hole or slit-shaped communication port that communicates the flow path with the outer surface of the catheter is attached to an inner diameter securing device near the distal end. The apparatus for securing the inner diameter of a body cavity according to claim 9, which is provided in a body cavity. (11) The catheter has an outer diameter near the distal end portion where the inner diameter securing device is attached, which is equal to or slightly larger than the inner diameter of the inner diameter securing device when it is contracted, and has a temperature substantially lower than body temperature. 11. The apparatus for securing an internal cavity of a body cavity according to claim 9 or 10, to which the internal diameter securing instrument can be attached. (12) The catheter includes a catheter lumen that extends from the proximal end to at least the vicinity of the proximal end, and
Claim 10 or 1, further comprising a hollow hub portion provided at the proximal end so as to communicate with the catheter lumen, and the flow path is formed by the catheter lumen and the hub portion lumen. The device for securing the inner diameter of a body cavity according to item 11. (13) The device for securing the inner diameter of a body cavity according to claim 12, wherein the hub portion is a branch hub having two ports, one of which is provided with a check valve. (14) In the catheter, the outer diameter of both the proximal end side and the distal end side of the inner diameter securing device mounting portion near the distal end, or the outer diameter of the proximal end side, is the inner diameter of the inner diameter securing device mounting portion. The device for securing the inner diameter of a body cavity according to any one of claims 9 to 13, which has an outer diameter equal to or larger than the outer diameter of the securing instrument. (15) The catheter has at least one
15. The device for securing the inner diameter of a body cavity according to any one of claims 9 to 14, comprising two X-ray opaque markers. (16) The catheter sheath may contain an X-ray opaque substance in its material, or may contain at least one radiopaque substance near its tip.
16. The device for securing the inner diameter of a body cavity according to any one of claims 9 to 15, comprising two X-ray opaque markers. (17) The catheter sheath includes a sheath lumen extending between both ends, and a hollow hub portion provided at the proximal end so as to communicate with the sheath lumen, and a check valve in the hub portion. Claims 9 to 16 provide
A device for securing the inner diameter of a body cavity according to any one of Items 1 to 3.