JP2001029475A - Blood perfusion balloon catheter - Google Patents

Abstract

(57) [Problem] To provide a centering function without lowering the perfusion function, without damaging the blood vessel wall even if the balloon ruptures, and capable of radiotherapy of a lesion site. It is to provide a blood perfusion balloon catheter. SOLUTION: The present invention provides a spiral groove 12a, 12b, 1 by spirally winding and joining a balloon 6 to a distal end outer peripheral surface of a shaft tube 5 provided with a pressure fluid supply tube 4.
2c is a blood perfusion balloon catheter in which a thin sleeve 7 is formed around the balloon 6 so as to cover these spiral grooves.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical dilatation catheter capable of dilating and treating a stenosis or an obstruction in a body cavity such as a blood vessel or a blood vessel. The present invention relates to a blood perfusion balloon catheter having a function.

[0002]

2. Description of the Related Art Conventionally, PTCA (Percutaneous Transluminal Coronary ATC) has been used for the treatment of intravascular stenosis, particularly coronary stenosis, which causes myocardial infarction and angina.
ngioplasty; percutaneous transluminal coronary angioplasty) A balloon catheter has been used. In this type of balloon catheter, a balloon that can be expanded, deflated, and folded by adjusting the internal pressure is joined to the distal end of a shaft tube having one or more lumens (lumens), and a manifold is joined to the proximal end of the shaft tube. It is configured as The shaft tube generally has at least two lumens: an inflation lumen for passing a pressure fluid for applying an internal pressure to the balloon, and a guide wire lumen for passing a guide wire for guiding a catheter.

[0003] A procedure using such a balloon catheter is performed in the following procedure. First, prior to guiding the balloon catheter to a lesion site such as a stenosis, a guiding catheter having an outer diameter of about 2 mm to 3 mm in the middle lumen is guided into the aorta, and the distal end thereof is placed at the entrance of the coronary artery. Then, a guide wire having an outer diameter of about 0.010 inch to 0.035 inch is passed through the guiding catheter to the lesion site of the coronary artery. Next, the balloon catheter is guided to the coronary artery along the guide wire, and the balloon is passed through and placed at the lesion site. Then, a pressure fluid such as a high-pressure physiological saline solution or a contrast medium is supplied to the balloon through the inflation lumen using a syringe or the like, and the balloon is inflated to forcibly dilate the lesion site. After confirming the dilation treatment, the balloon was deflated under reduced pressure and removed from the body.
End CA.

[0004] However, PTCA does not
Restenosis (repetitive stenosis) is about 40% in a short period of ~ 6 months
There is a problem that occurs with probability. As a mechanism of restenosis, it has been proved that forcible dilation of a blood vessel lumen by a balloon damages the blood vessel wall and is caused by excessive proliferation of smooth muscle cells in the subsequent healing process. In addition, it has been confirmed that if a stent (metal mesh or coil) is placed in the stenotic part after dilatation treatment of the stenotic part, the occurrence rate of restenosis is reduced to 20% or less. However, there is an urgent need to reduce this incidence as much as possible in clinical terms.

On the other hand, in recent years, as a method for preventing restenosis in the United States and Europe, a clinical practice of an intravascular irradiation treatment method in which a lesion site is irradiated with an appropriate dose of radiation after balloon inflation to suppress cell proliferation in the healing process. Although some clinical trials have reported that the incidence of restenosis can be reduced to about 7%, although some clinical trials have been pursued.

[0006] Such a radiation irradiation treatment is performed in the following procedure. First, after a dilatation treatment of a lesion site using a PTCA balloon catheter as described above, or after a stent is placed at the lesion site, the catheter is removed from the body, and then an intravascular radiation treatment having a tubular shaft whose tip is sealed is performed. The catheter is guided to reach the lesion site. Then, a wire having a radiation source near the distal end (referred to as a radiation wire) as disclosed in U.S. Pat. No. 5,199,939 is passed through the lumen of the tubular shaft to the lesion site. 20Gray to 30Gr at the lesion site for a predetermined time
A radiation dose of about ay is applied. After the radiation irradiation, the radiation wire is pulled out of the body (recovery), and the radiation treatment is terminated. In addition, guidance and collection work of radiation wire,
As is generally performed in the field of cancer treatment, it is usually performed by remote automatic operation by a remote loader / unloader to prevent the operator from being exposed to radiation. For a catheter using this type of radiation source, see
No. 507951 (“Method of treating vascular system”) and US Pat. No. 5,302,168 (“METHOD AND APPARATUS”).
FOR RESTENOSIS TREATMENT ") and U.S. Pat. No. 5,213,561 (" METHOD AND DEVICES FOR
PREVENTING RESTENOSIS AFTER ANGIOPLASTY ").

In recent years, in clinical application of such radiation irradiation treatment, it is necessary to (1) uniformly irradiate the blood vessel wall with radiation, and (2) during dilation treatment or irradiation with a balloon catheter, A mechanism (hereinafter, referred to as a perfusion mechanism) for securing blood flow to a more distal (peripheral) blood vessel without blocking the lesion site is required. Regarding the above (1), when the radiation source that irradiates the lesion site is positioned significantly deviated from the center position of the cross section of the blood vessel lumen, the blood vessel wall near the radiation source receives excessive irradiation and necrosis of the vascular tissue In contrast to the high risk of causing an aneurysm, etc., it is difficult for a blood vessel wall far from the radiation source to receive a sufficient dose to suppress smooth muscle proliferation. This is because the intensity of the radiation decreases rapidly as one moves away from the source. Therefore, there is a demand for a mechanism capable of arranging a radiation source at a substantially central position of a cross section of a blood vessel lumen, that is, a so-called centering mechanism so that a blood vessel wall can be irradiated with a dose as uniform as possible.

[0008] Regarding the above (2), when the radiation source is β-rays, the required irradiation time is about 5 to 10 minutes, and when the radiation source is γ-rays, the irradiation time is as long as about 10 to 30 minutes. Although it is necessary, if the blood vessel lumen is closed during such a long irradiation time, for example, coronary artery blood is not supplied to the peripheral coronary artery blood vessels, and peripheral myocardial cells become ischemic, and angina and the like May cause serious symptoms. Therefore, radiotherapy requires a hemoperfusion mechanism.

Various prior arts which can simultaneously realize the above centering mechanism and perfusion mechanism have been proposed. For example, Japanese Patent Publication No. 9-507783 discloses a spiral balloon as one means for realizing a centering mechanism. For example, as shown in FIG. 7, a tubular balloon 32 is spirally wound around a catheter shaft tube 31 whose distal end is sealed by a plug member 30. The radiation sources 33a, 33b are guided and positioned near the distal end of the lumen 31a of the catheter shaft tube 31 in a state sealed in the elongated hollow cylindrical body 34, and the helical balloon 32 is a pressure fluid. It is inflated by the pressure fluid supplied from the supply tube 36 and expands the blood vessel wall 37, and simultaneously positions (centers) the radiation sources 33a and 33b substantially at the center of the blood vessel lumen. Also, during this time,
Blood is perfused through the spiral grooves 38a, 38b, 38c of the spiral balloon.

[0010]

However, in the spiral balloon as described above, as shown in FIG. 7, when the balloon 32 is expanded, the flexible blood vessel wall 37 bites into the spiral grooves 38a, 38b, 38c. Therefore, there has been a problem that the blood cross-sectional area is reduced and the perfusion function is reduced.

The helical balloon is used not for dilating the stenosis but for the centering function, so that it usually does not have high pressure resistance. However, in vasodilation such as PTCA, a cardiologist accustomed to inflating the balloon at a high pressure of 14 atm or more forgot to inflate the helical balloon at a low pressure, and inadvertently applied a high pressure. In some cases. In such a case, the balloon ruptures, and
As much as 6 atm of the balloon expansion pressure fluid becomes a jet stream at a time and is ejected toward the blood vessel wall, thereby damaging the blood vessel wall. Therefore, this is a very serious safety issue.

[0012] The present invention has been made in view of the above problems, and does not reduce the perfusion function, does not damage the blood vessel wall even if the balloon ruptures, and further provides a radiation treatment for a lesion site. And a blood perfusion balloon catheter having a centering function.

[0013]

In order to solve the above problems,
In the blood perfusion balloon catheter of the present invention, at least near the distal end of a shaft tube provided with a pressure fluid supply lumen, a balloon communicating with the lumen is formed so as to form a blood perfusion groove, and A thin sleeve is formed around the balloon so as to cover the blood perfusion groove. That is, even when the inner wall of the body cavity such as the blood vessel wall is flexible in the affected part, the thin sleeve covering the periphery of the balloon prevents the inner wall of the body cavity from entering the blood perfusion groove, thereby preventing the blood flow. It is possible to secure a sufficient area, and furthermore, even if the balloon ruptures, it is possible to prevent the jet flow of the balloon expanding pressure fluid from being jetted.

As a more specific configuration, a spiral groove between the balloons formed by spirally winding and joining a balloon on the outer peripheral surface of the distal end of the shaft tube is formed as the blood perfusion groove, and the spiral groove is formed. The thin sleeve may be formed around the balloon so as to cover the balloon.

[0015] Further, in order to realize the above-mentioned centering mechanism, the shaft tube may be provided with a lumen through which a radiation source for irradiating the lesion site with radiation to near the distal end.

Further, in order to prevent the flexible thin sleeve from biting into the spiral groove and impairing the blood perfusion function, it is preferable to adjust the axial width of the spiral groove to be less than 1.5 times the expanded diameter of the balloon. .

Such a thin sleeve is made of ASTM D
Preferably, the thin sleeve is made of a material having an elongation of 500% or more according to the method of 638.
Desirably, it is composed of one or more selected from silicone, polytetrafluoroethylene, thermoplastic elastomer, natural rubber and synthetic rubber.

The main component of the balloon is one or more selected from polyurethane, polyamide, polyamide elastomer, polyester resin, polyester elastomer, polyolefin resin, silicone, natural rubber and synthetic rubber. Is desirable.

[0019]

FIG. 1 is a sectional view of a main part of a typical embodiment of a blood perfusion balloon catheter according to the present invention. FIG. 2A is a sectional view taken along the line AA 'of FIG. FIG. 2B is a sectional view taken along the line BB ′ shown in FIG. The balloon catheter 1 is provided with a shaft tube 5 formed by bundling a tube 2 for passing a radiation source, a tube 3 for passing a guide wire, and a tube 4 for expansion. A spiral balloon 6 communicating with the lumen 4 a of the tube 4, a thin sleeve 7 formed around the spiral balloon 6, and a proximal end of the shaft tube 5 The pressure fluid supply port 8a communicating with the lumen 4a and the lumen 2 of the radiation source passage tube 2
and a manifold 8 having a radiation source insertion port 8b communicating with a. In FIG. 1,
For ease of explanation, the vicinity of the distal end of the balloon catheter 1 is enlarged and displayed as compared to the vicinity of its proximal end.

The guide wire passage tube 3
A guide wire (not shown), which is introduced into the lesion site prior to the catheter, is inserted through the lumen. The balloon catheter according to the present embodiment has a so-called monorail type balloon in which the guide wire passage tube 3 is provided only at the distal end of the catheter, and the guide wire is inserted through the guide wire outlet 3a in the middle of the catheter. Although it is a catheter, the present invention is not limited to this, and the guide wire passage tube may be of the over-the-wire type over the entire length of the catheter.

The extension tube 4, the guide wire passage tube 3, and the radiation source passage tube 2
As shown in FIGS. 2 (a) and 2 (b), as shown in FIGS. 2 (a) and 2 (b), together with a reinforcing wire 9 whose diameter gradually decreases toward the distal side, coating tubes 10a and 10b such as heat-shrink tubes (shown in FIG. 1). ) To form a shaft tube 5. The reinforcing wire 9 is a member necessary for favorably transmitting the pushing force applied from the manifold 8 to the distal side to the distal end of the catheter. The distal end of the radiation source passage tube 2 is sealed with a plug member 11 to prevent the radiation source from leaking into the body for safety. The various tubes 2, 3, and 4 constituting the shaft tube 5 are manufactured by an extrusion molding method when made of a thermoplastic resin, and by a dip / cure molding method when made of a thermosetting resin such as polyimide. Is done.

The helical balloon 6 is formed by winding a tubular balloon around the distal end of the shaft tube 5 and bonding it to the outer peripheral surface thereof by bonding or heat welding, for example, and connecting the tubular balloon to the proximal end 6c of the tubular balloon. The inner cavity 6a of the balloon and the inner cavity 4a of the expansion tube 4 communicate with each other by bonding or heat welding the distal end of the expansion tube 4. In the case of bonding, "4011" (Loc
cyanite acrylate adhesives such as
A V-curable adhesive or a urethane-based adhesive may be used. In addition, the tubular balloon is formed by blow molding.
Although it is formed by axial stretching or biaxial stretching, an example of a specific manufacturing procedure is as follows. First, preferably,
Polyurethane, polyamide (nylon 66, nylon 1
2), a polyamide elastomer, a polyester resin, a polyester elastomer, a polyolefin resin, silicone, a natural rubber and a synthetic rubber selected from one or more blends of resin materials by extrusion molding. To make a parison,
The parison is stretched in the axial direction by a factor of 2 to 7 times. Next, the tubular parison is transferred to a cavity in a blow mold, the mold is closed, compressed air is blown into the parison to inflate the parison, and the parison is molded into a cavity shape to produce a tubular balloon. is there.
Here, in order to stabilize the shape and dimensions of the balloon, the tubular balloon may be subjected to a heat fixing treatment. still,
As a method for manufacturing the above-mentioned tubular balloon, Japanese Patent Application Laid-Open No.
A uniaxial stretching or a biaxial stretching blow molding method as disclosed in JP-A-3-183070 may be used.

Next, the thin sleeve 7 formed around the helical balloon 6 is formed of at least one kind selected from silicone, polytetrafluoroethylene, thermoplastic elastomer, natural rubber and synthetic rubber. Formed by extrusion molding, dip / cure molding, or the like, using a resin material of the above blend. This may be a heat-shrinkable tube.
However, among the above-mentioned resin materials, in order to be able to flexibly follow the deformation of the balloon in response to the contraction and expansion of the balloon, a material having a moderate elongation rate, that is, a grade showing a so-called rubber characteristic is preferable. Specifically, the elongation according to ASTM D638 is preferred. Rate 500
% Or more is preferable. FIG. 3 is a view showing a state in which the spiral balloon is decompressed and deflated, that is, a state in which the spiral balloon 6 is introduced into a lesion site. When the state is shifted from this state to the expanded state shown in FIG. If the thin sleeve 7 does not have an appropriate elongation, the thin sleeve 7
Reaches the ultimate elongation and stops growing further,
This impairs the expansion of the balloon, resulting in a failure that the balloon does not reach the maximum specified expanded diameter.

As shown in FIG. 1, the axial width d of the spiral grooves 12a, 12b,... When the balloon is expanded is preferably less than 1.5 times the expanded diameter Di of the balloon 6, more preferably 1.times. It is adjusted to be less than 3 times, more preferably less than 1.2 times. This is because, when the width d becomes 1.5 times or more of the expanded diameter Di, as shown in FIG. 4, the thin sleeve 7 bites into the spiral grooves 12a, 12b,... It is.

FIG. 5 shows how the above-mentioned blood perfusion balloon catheter 1 is actually used. In the lumen of the radiation source passage tube 2, radiation sources 14a, 14b, 14c, and 14d sealed inside the hollow cylindrical body 13 are introduced and positioned near the distal end of the catheter. The radiation sources 14a, 14a
An X-ray opaque marker 15 is provided for ascertaining the positions in the body of b, 14c, and 14d. In this state, the helical balloon 6 expands under the application of an internal pressure to expand the blood vessel wall 16 and at the same time, the radiation sources 14a, 14b, 14c,
14d is centered. In addition, the said hollow cylinder 1
3 may be composed of a coated tube such as a heat-shrinkable tube or a thermoplastic tube.
As disclosed in Japanese Patent Publication No. 07951, it may be made of stainless steel, silver, titanium or the like. In the case of the former, it is preferable to arrange a reinforcing wire (not shown) along the axis in the inside of the hollow cylindrical body 13 closer to the radiation source 14d. It is preferable to coat or coat the outer surface of 13 with a low friction material such as a polytetrafluoroethylene material.

Next, another embodiment of the blood perfusion balloon catheter according to the present invention will be described. FIG. 6 is a cross-sectional view of a main part showing the vicinity of the distal end of the blood perfusion balloon catheter. The same components as those in the above-described embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

A balloon catheter 20 shown in FIG. 6 covers the entire helical balloon 6 with a thin sleeve 21 made of the same material as that of the first embodiment, and the inner peripheral surfaces of both ends 21a and 21b of the thin sleeve 21 are shafts. The thin-walled sleeve 2 is bonded to the outer peripheral surface of the tube 5 or thermally welded.
1 is formed by forming blood perfusion holes 21c and 21d on the proximal side and the distal side. The thin sleeve 21 in which the blood perfusion holes 21c and 21d are formed in advance may be joined to the outer peripheral surface of the shaft tube 5. Depending on the material of the thin-walled sleeve 21, the thin-walled sleeve 21 and the shaft tube 5 can be separated from each other due to friction between the lesion site and the inner wall of the body cavity during the operation, and the two can be easily separated.
With the configuration of the present embodiment, it is possible to reliably prevent the peeling.

In the above embodiment, only the helical balloon is shown. However, the present invention is not limited to this. The present invention is applicable to all balloon catheters having balloons of various shapes provided with blood perfusion grooves.

In the above-described embodiment, the guide wire outlet formed at the proximal end of the guide wire passage tube is provided on the proximal side of the balloon. A guidewire outlet may be provided proximally and the guidewire outlet may be provided distally of the balloon.

In the above embodiment, the intravascular irradiation therapy catheter for preventing coronary restenosis has been described. However, the vascular perfusion balloon catheter according to the present invention can be applied to peripheral blood vessels other than coronary arteries, or can be used for dialysis shunt revascularization. It goes without saying that the present invention can be applied to the prevention of stenosis, and further to all medical devices that require a centering function and a blood perfusion function in vessels and tissues other than blood vessels in the body.

[0031]

EXAMPLES Based on the above embodiment, more specific examples will be described in detail below, but the balloon catheter of the following examples does not limit the present invention at all.

Example 1 A blood perfusion balloon catheter 1 as shown in FIG. 1 was prepared by the following procedure.
And First, the outer diameter of the expansion tube 4 is φ
0.46mm, inner diameter φ0.40mm, total length 128c
A polyimide tube of about m was used. This polyimide tube is manufactured by immersing a core material having an inner diameter of about 0.40 mm in a varnish containing polyimide as a main component, pulling it up, and repeatedly performing a heat-curing procedure until the outer diameter becomes 0.46 mm. Was done.

The guide wire passing tube 3 is formed by extruding a polyethylene tube having an outer diameter of 0.54 mm, an inner diameter of 0.42 mm, and a total length of about 25 cm by extrusion molding. 2,
A polyethylene tube having an outer diameter of φ0.60 mm, an inner diameter of φ0.42 mm, and a total length of about 127.5 cm was extruded and used. The outer diameter of the reinforcing wire 9 is φ0.30.
A stainless steel having a diameter gradually reduced from 0.1 mm to 0.18 mm was used.

After the expansion tube 4, the guide wire passage tube 3, the radiation source passage tube 2, and the reinforcing wire 9 are bundled in the arrangement shown in FIGS. 1 and 2, the tube is made of polytetrafluoroethylene. A heat-shrinkable tube is disposed around each of the distal shaft and the proximal shaft except for the guide wire outlet 3a, and is shrunk by applying hot air to the various tubes 4, 3, 2 and a reinforcing wire. 9 were mutually fixed.

Further, the lumen 2 of the radiation source passage tube 2
The distal end of a was sealed with a plug member 11.

The proximal ends of the expansion tube 4 and the radiation source passage tube 2 are respectively connected to the pressure fluid supply port 8a and the radiation source insertion port 8b of the Y-shaped manifold 8 by cyano. Airtight bonding was performed using an acrylate-based adhesive (“Loctite 4011”).

On the other hand, the balloon 6 according to the present embodiment was manufactured in the following procedure. First, polyurethane (“Milactran E395NAT”; manufactured by Nippon Milactran Co., Ltd.) was used as the resin material, and the inner diameter was φ0.23 mm and the outer diameter was φ0.3.
It was extruded into a tubular parison having a length of 7 mm and a length of about 25 cm. Next, this tube-shaped parison is stretched about 2.5 times in the axial direction at room temperature, and then transferred to a cavity in a blow molding die and mounted. Then, one end is plugged, and the other end is compressed with high-pressure air. Source connected. In this state, the blow molding mold is heated to about 50 ° C., and 8 atm of air is blown into the inside of the tubular parison to be inflated to form a balloon having a desired shape. Then, in order to improve the dimensional stability of the balloon. After the mold was heated to about 85 ° C. and heat-treated for 2 minutes while adjusting the air pressure to 6 atm, a tubular balloon (outer diameter φ1.00 mm; inner diameter φ) was formed.
0.972 mm).

Such a balloon was spirally wound around the outer peripheral surface near the distal end of the shaft tube 5 and joined with an adhesive to form a spiral balloon 6. If the constituent resins of the helical balloon 6 and the shaft tube 5 are the same, both may be thermally welded. The distal end 6b of the helical balloon 6 was flat and thermally deformed to make it airtight, and then bonded near the tip end of the shaft tube 5 using an adhesive to form a minimum step.
On the other hand, the proximal end 6c of the helical balloon 6 was bonded to the distal end of the dilation tube 4 using a cyanoacrylate-based adhesive ("4011"; Loctite) so as to be airtight.

As the thin sleeve 7, a tube made of a silicone elastomer having an outer diameter of about 1.30 mm and an inner diameter of about 1.00 mm was used. As shown in FIG. 3, while the helical balloon 6 joined to the shaft tube 5 was decompressed and contracted, the inner peripheral surfaces of both ends of the thin sleeve 7 and the outer peripheral surface of the helical balloon 6 were joined with a urethane adhesive. In order to increase the bonding strength between the two, it is preferable that the joint surface is previously subjected to a plasma treatment and modified. This is because when the constituent resin of the thin sleeve 7 is silicone and the constituent resin of the shaft tube 5 is polyethylene, they are difficult to adhere to each other. Both ends 7a and 7b of the thin sleeve 7 are joined so as to face inward in order to reduce a step.

When the spiral balloon of the balloon catheter thus produced is expanded at an internal pressure of 4 atm,
The expanded diameter Di was φ3.2 mm. Spiral groove 12a, 1
Since the axial width d of 2b,... Was adjusted to 0.8 mm,
This value is less than 1.5 times the expanded diameter Di.

Example 2 A blood perfusion balloon catheter 20 as shown in FIG. The same shaft tube 5 and helical balloon 6 as in the first embodiment are prepared, and as the thin sleeve 21,
A silicone elastomer tube having an outer diameter of 1.30 mm and an inner diameter of 1.00 mm was prepared, and a spiral balloon 6 was prepared.
This thin-walled sleeve 21 is arranged so as to cover the entire helical balloon 6 in a state where it is decompressed and contracted, and the inner peripheral surfaces of both end portions 21a and 21b of the thin-walled sleeve 21 Glued. In addition, the blood perfusion hole 2 is provided on the proximal side and the distal side of the thin sleeve 21.
By forming 1c and 21d, the balloon catheter of this example was manufactured.

When the balloon catheters of Examples 1 and 2 were actually used, and the situation was observed by X-ray contrast, even if the helical balloon was expanded, the presence of the thin-walled sleeve covering the helical balloon caused the balloon to expand. It was confirmed that the flexible blood vessel wall did not penetrate into the spiral groove and blood perfusion was good.

[0043]

As described above, in the blood perfusion balloon catheter of the present invention, the lumen is formed so as to form a blood perfusion groove at least near the distal end of a shaft tube having a pressure fluid supply lumen. And a thin-walled sleeve is formed around the balloon so as to cover the blood-perfusion groove. Therefore, due to the presence of the thin-walled sleeve, the blood-perfusion groove has a flexible inner cavity wall. Is prevented from penetrating and invading, so that the blood perfusion function can be sufficiently exhibited.Furthermore, even if the balloon ruptures, the surrounding area of the balloon is covered with the thin-walled sleeve. Jet flow can be prevented, and safety can be improved.

Further, even when the shaft tube has a lumen through which a radiation source for irradiating the lesion site with radiation to the vicinity of the distal end and has a perfusion function and a centering function, the blood perfusion may be performed. It is possible to fully demonstrate the function.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing an embodiment of a blood perfusion balloon catheter according to the present invention.

FIGS. 2A and 2B are schematic cross-sectional views of the balloon catheter shown in FIG. 1, in which FIG. 2A is a cross-sectional view along AA ′ and FIG. 2B is a cross-sectional view along BB ′.

FIG. 3 is a schematic cross-sectional view showing a state in which the spiral balloon according to the present invention is decompressed and contracted.

FIG. 4 is a schematic cross-sectional view showing a state in which a thin-walled sleeve bites into a spiral groove of a spiral balloon.

FIG. 5 is a schematic cross-sectional view showing a state where an irradiation source is centered by inflating a balloon at a lesion site.

FIG. 6 is a sectional view of a main part showing another embodiment of the blood perfusion balloon catheter according to the present invention.

FIG. 7 is a schematic view showing a partial cross section of a conventional blood perfusion balloon catheter.

[Explanation of symbols]

 Reference Signs List 1 balloon catheter 2 radiation source passage tube 2a lumen of radiation source passage tube 3 guide wire passage tube 3a guide wire outlet 4 extension tube 4a lumen of extension tube 5 shaft tube 6 spiral balloon 6a of balloon Lumen 6b Distal end of balloon 6c Proximal end of balloon 7 Thin sleeve 8 Manifold 8a Port for supplying pressure fluid 8b Port for inserting radiation source 9 Reinforcing wire 10a, 10b Coating tube 11 Plug member 12a, 12b, 12c Spiral Groove 13 Inner cavity 14a, 14b, 14c, 14d Radiation source 15 Radiopaque marker 20 Blood perfusion balloon catheter 21 Thin sleeve 21a Distal end of thin sleeve 21b Proximal end of thin sleeve 21c, 21d Blood perfusion hole 30 stopper Material 31 catheter shaft tube 32 tubular balloon 33a, in 33b the radiation source 34 腔円 cylinder 35 X-ray opaque marker 36 pressure fluid supply tube 37 blood vessel wall 38a, 38b, 38c helical groove

Claims (7)

[Claims] 1. A balloon that communicates with the lumen so as to form a blood perfusion groove at least near a distal end of a shaft tube having a lumen for supplying a pressure fluid, and A blood perfusion balloon catheter, wherein a thin-walled sleeve is formed so as to cover the blood perfusion groove. 2. A helical groove between balloons formed by helically winding and joining a balloon on the outer peripheral surface of the distal end of the shaft tube is formed as the blood perfusion groove, and the helical groove is formed so as to cover the helical groove. The blood perfusion balloon catheter according to claim 1, wherein the thin sleeve is formed around the balloon. 3. The perfusion inflation catheter according to claim 1, wherein the shaft tube has a lumen through which a radiation source that irradiates the lesion site with radiation is proximate to a distal end. 4. The blood perfusion balloon catheter according to claim 1, wherein an axial width of the spiral groove is adjusted to be less than 1.5 times an expanded diameter of the balloon. 5. The thin-walled sleeve according to ASTM D63.
The blood perfusion balloon catheter according to any one of claims 1 to 4, comprising a material having an elongation rate of 500% or more according to the method of (8). 6. The blood perfusion balloon according to claim 5, wherein the main component of the thin-walled sleeve is at least one selected from silicone, polytetrafluoroethylene, thermoplastic elastomer, natural rubber and synthetic rubber. catheter. 7. The main component of the balloon is one or more selected from polyurethane, polyamide, polyamide elastomer, polyester resin, polyester elastomer, polyolefin resin, silicone, natural rubber and synthetic rubber. Claim 1
7. The blood perfusion balloon catheter according to any one of items 6 to 6.