WO2013121726A1 - Covered stent - Google Patents

Abstract

This covered stent is a covered stent capable of being positioned to remain in a lumen of an organism, and provided with: a stent body that is substantially cylindrical and has an opening on the circumferential surface thereof; and a cylindrical cover for covering at least part of the circumferential surface of the stent body. Therein, the cylindrical cover has a layer comprising a material for preventing leakage of a body fluid from the interior of the lumen of the organism to the exterior thereof during or after puncturing of the lumen of the organism.

Description

Covered stent

The present invention relates to a covered stent, and more particularly, to a covered stent placed in a living body lumen.

Conventionally, various stents have been proposed for insertion into biological lumens such as blood vessels, bile ducts, esophagus, trachea, and urethra.
As this stent, (i) In order to prevent restenosis invading between metallic struts of a metallic stent (for example, refer to Patent Document 1) formed of a metal such as nickel titanium alloy and (ii) metallic stent, There is a covered stent (see, for example, Patent Document 2) provided with a cover that covers the peripheral surface of the metallic stent.
Here, a fluororesin film, a polyolefin film, a polyester film, or the like is used as a cover material of the covered stent.

On the other hand, cranial nerve diseases include epilepsy, Parkinson's disease, trigeminal neuralgia, etc., and there are many patients for each, and treatment is required.

“Epileptic” is a disease that causes irregular muscle spasms, loss of consciousness, impaired consciousness, etc. due to abnormal electrical signals from lesions (cells that generate abnormal electrical signals and nerves that transmit such signals). .
Treatment of such “epilepsy” is centered on treatment by drug administration, but the effect of treatment by drug administration may not be obtained. In such a case, craniotomy is performed and the lesion is surgically removed. Etc. are done.

“Parkinson's disease” is a disease in which dopamine produced in the midbrain is reduced, resulting in abnormal neurotransmission and inability to smoothly exercise the body.
As for the treatment of such “Parkinson's disease”, treatment by drug administration is the center, but the effect of treatment by drug administration may not be obtained, in which case, the head is opened and an electrode is implanted in the lesion, Giving electrical stimulation.

The treatment of “trigeminal neuralgia” is centered on treatment by drug administration, but there may be cases where the effect of treatment by drug administration cannot be obtained.In that case, the nerve that causes trigeminal neuralgia is opened. Cutting with a high-frequency probe using surgery or heat is performed.

In this way, for cranial nerve diseases such as epilepsy, Parkinson's disease, trigeminal neuralgia, etc., if the therapeutic effect of drug administration cannot be obtained, a highly invasive treatment such as craniotomy may be performed. There is a need for a less invasive treatment other than administration.

In order to realize treatment with low invasiveness other than drug administration for cranial nerve diseases, a stimulus applying member such as a coil is sent into the cerebral blood vessel using a catheter, and delivered from inside the cerebral blood vessel to outside the cerebral blood vessel. Thus, the inventors of the present application have newly created an epoch-making treatment method for imparting mechanical stimulation to a lesioned part by placing it in the vicinity of the lesioned part outside the cerebral blood vessel.

In this new treatment method, a covered stent is used to secure a cerebrovascular space. However, when the conventional covered stent is used in this new treatment method, the puncture member is inserted from the cerebral blood vessel into the cerebral blood vessel in order to provide a passage for delivering the stimulus applying member from the cerebral blood vessel to the outside of the cerebral blood vessel. A new problem that blood leaks out of the cerebral blood vessel through the puncture hole when puncturing the (cerebral blood vessel wall) and after puncturing, that is, the conventional usage of preventing restenosis by inserting into the body lumen A new problem that did not exist arises.

Therefore, in order to put this new treatment method into practical use, even when the puncture member is punctured from a living body lumen such as a blood vessel into the living body lumen, the body fluid (for example, blood) goes out of the living body lumen. Therefore, it is necessary to develop a covered stent that can sufficiently reduce the leakage.

Further, when the covered stent is used in this new treatment method, for example, as shown in FIG. 17, the catheter 5 escapes from the segment 2 of the covered stent 1 in a cross section along the axis of the covered stent 1. The catheter 5 cannot be held at a position where the tubular cover 1b and the blood vessel 3 (blood vessel wall 3a) can be punctured from the inside to the outside of the blood vessel 3 (a position in the vicinity of the opening X). A new problem that the tip 5a of the catheter 5 or a puncture member (not shown) delivered by the catheter 5 cannot be punctured from inside the blood vessel into the blood vessel 3 (blood vessel wall 3a), that is, inserted into the living body lumen. There arises a new problem that has not occurred in the conventional usage of preventing stenosis.

Therefore, in order to put this new treatment method into practical use, it is necessary to develop a covered stent that can easily puncture a living body lumen (living body wall) from within the living body lumen.

Special table 2002-501409 gazette JP 2001-327609 A

The present invention is sufficient for the practical use of a new treatment method, even when the puncture member is punctured from the inside of the living body lumen into the living body lumen. An object of the present invention is to provide a covered stent that can be reduced.

As a result of intensive studies to achieve the above object, the present inventors have found that the cylindrical cover is punctured from inside the living body lumen into the living body lumen and outside the living body lumen of the body fluid after being punctured. By having a layer made of a material that prevents leakage of body fluid, leakage of bodily fluids outside the body lumen can be sufficiently reduced even when the puncture member is pierced from the body lumen into the body lumen. As a result, the present invention has been completed.

The present invention is based on the above findings by the present inventors, and means for solving the above problems are as follows. That is, the covered stent of the present invention comprises (i) a substantially cylindrical shape, and a stent main body having an opening on the peripheral surface, and (ii) a cylindrical cover that covers at least a part of the peripheral surface of the stent main body. A covered stent that can be placed in a living body lumen, wherein the cylindrical cover is inserted into the living body lumen from inside the living body lumen and after being pierced to the outside of the living body lumen. It has a layer made of a material that prevents leakage.
When the cylindrical cover has a layer made of a material that prevents leakage of body fluid to the outside of the living body lumen when the living body lumen is punctured from the inside of the living body lumen and after the puncturing, the puncture member becomes a living body. Even when the living body lumen is punctured from the inside of the lumen, leakage of body fluid to the outside of the living body lumen can be sufficiently reduced.
In addition, restenosis that enters between segments in the stent body can be prevented.

In the covered stent of the present invention, the material for preventing leakage of the body fluid to the outside of the living body lumen is preferably an elastomer.
When the material for preventing leakage of the body fluid to the outside of the living body lumen is an elastomer, (i) leakage of the body fluid from the puncture hole and (ii) oozing (exudation) of the body fluid can be sufficiently reduced. Therefore, the leakage of body fluid to the outside of the body lumen can be reduced more sufficiently.

In the covered stent of the present invention, the cylindrical cover may be composed only of an elastomer layer. Here, the elastomer layer is at least one layer, and may have either a single layer structure or a multilayer structure.

In the covered stent of the present invention, it is preferable that the cylindrical cover includes an inner layer, an outer layer, and an intermediate layer provided between the inner layer and the outer layer.
When the cylindrical cover includes an inner layer, an outer layer, and an intermediate layer provided between the inner layer and the outer layer, leakage of body fluid to the outside of the body lumen can be more sufficiently reduced.

In the covered stent of the present invention, it is preferable that the inner layer and the outer layer are layers made of polyester fibers, and the intermediate layer is a layer made of a material that prevents the body fluid from leaking out of the body lumen.
In the tubular cover, the inner layer and the outer layer are layers made of polyester fibers, and the intermediate layer is a layer made of a material that prevents leakage of the body fluid outside the body lumen. Leakage to the outside can be reduced more sufficiently, and handling properties can be improved.

In the covered stent of the present invention, it is preferable that the stent body has a receiving surface for holding the delivery device at a position where the living body lumen can be punctured from the inside to the outside of the living body lumen.
When the stent body has a receiving surface for holding a delivery device, a catheter or the like can be placed at a position (position near the opening) where the living body lumen (living body wall) can be punctured from the inside of the living body lumen to the outside. The delivery device of the present invention can be easily held, so that the lumen space of the living body lumen can be secured, and the living body lumen (living body wall) can be easily punctured from within the living body lumen. it can.

In the covered stent of the present invention, in the cross section along the axis of the covered stent, the stent body is in linear contact with the cylindrical cover or the living body lumen, and the straight line passing through the two ends of the receiving surface and the opening It is preferable that the angle formed by the straight line by the part is more than 0 ° and not more than 90 °.
In the cross section along the axis of the covered stent, the stent body is in line contact with the cylindrical cover or the living body lumen, and an angle formed by a straight line passing through two ends of the receiving surface and a straight line by the opening However, if it is more than 0 ° and not more than 90 °, a delivery device such as a catheter is placed at a position where the living body lumen (living body wall) can puncture from the inside of the living body lumen to the outside (position near the opening). It can be held more easily.

In the covered stent of the present invention, in a cross section along the axis of the covered stent, an angle formed by a straight line passing through two end portions of the receiving surface and a straight line by the opening is preferably 30 ° to 90 °. .
In the cross section along the axis of the covered stent, if the angle formed by the straight line passing through the two end portions of the receiving surface and the straight line by the opening is 30 ° to 90 °, the inside of the living body lumen is extended from the inside to the outside. A delivery device such as a catheter can be more easily held at a position (position in the vicinity of the opening) where it can puncture the living body lumen (living body lumen wall).

In the covered stent of the present invention, it is preferable that the receiving surface includes a flat surface.
When the receiving surface includes a flat surface, the delivery device can be more easily held at a position where the living body lumen (living body wall) can puncture from the inside of the living body lumen to the outside (position near the opening). Can do.

In the covered stent of the present invention, the receiving surface may include a curved surface.

In the covered stent of the present invention, the delivery device may be a catheter.

According to the present invention, the above-described object can be achieved, and even when the puncture member is punctured from the living body lumen into the living body lumen, leakage of body fluid to the outside of the living body lumen can be sufficiently reduced. A covered stent can be provided.

FIG. 1 is a perspective view showing an example of a covered stent of the present invention. FIG. 2 is an explanatory view showing an example of a state where the covered stent of the present invention is placed in a blood vessel. FIG. 3 is a development view of the main stent body in FIG. FIG. 4 is an explanatory view for explaining the spiral shape of the frame structure used in the covered stent of the present invention (No. 1). FIG. 5 is an explanatory diagram for explaining the spiral shape of the frame structure used in the covered stent of the present invention (part 2). Drawing 6 is an explanatory view showing an example of the usage method of the covered stent concerning a 1st embodiment of the present invention (the 1). Drawing 7 is an explanatory view showing an example of the usage method of the covered stent concerning a 1st embodiment of the present invention (the 2). FIG. 8 is an explanatory diagram showing an example of a method for using the covered stent according to the first embodiment of the present invention (part 3). FIG. 9 is an explanatory diagram showing an example of a method for using the covered stent according to the first embodiment of the present invention (part 4). FIG. 10 is a partial cross-sectional view of the covered stent of FIG. FIG. 11 is a perspective view showing another example of the covered stent of the present invention (when the cylindrical cover covers the entire peripheral surface of the stent body). FIG. 12 is a partial cross-sectional view showing another example of the covered stent of the present invention (when the cylindrical cover is formed only on the outer peripheral surface of the stent body). FIG. 13 is a partial cross-sectional view showing another example of the covered stent of the present invention (when the cylindrical cover is formed only on the inner peripheral surface of the stent body). FIG. 14 is an explanatory diagram illustrating another example of the delivery device that delivers the treatment device according to the first embodiment of the present invention. FIG. 15 is an explanatory diagram showing an example of a method of using a covered stent according to the second embodiment of the present invention (part 1). FIG. 16 is an explanatory diagram illustrating an example of a method of using a covered stent according to the second embodiment of the present invention (part 2). FIG. 17 is an explanatory diagram showing an example of a cross section along the axis of the covered stent. FIG. 18 is an explanatory diagram showing another example of a cross section along the axis of the covered stent. FIG. 19 is an explanatory view showing still another example of a cross section along the axis of the covered stent. 20 is a partial cross-sectional view of the covered stent of FIG.

(Covered stent)
The covered stent of the present invention includes at least a stent body and a cylindrical cover, and further includes other members as necessary.
For example, as shown in FIG. 1, the covered stent has a substantially cylindrical shape (formed in a substantially cylindrical shape), and has a stent main body 1a having an opening X on the peripheral surface, and at least one of the peripheral surfaces of the stent main body 1a. And a cylindrical cover 1b that covers the part, and as shown in FIG. 2, is configured to be placed inside a blood vessel 3 as a living body lumen.

<Stent body>
-Types of stent body-
The type of the stent body is not particularly limited and can be appropriately selected depending on the purpose. For example, (i) when compressed into a living body, the diameter is compressed and reduced, and when placed in a living body lumen, the stress load is released. And so-called self-expandable stents that are restored to the shape before contraction, and (ii) balloon expandable stents that do not self-expand.

-Shape and structure of stent body-
There is no restriction | limiting in particular as a shape of the said stent main body, According to the objective, it can select suitably, For example, substantially cylindrical shape (spiral shape), knitted fabric shape, etc. are mentioned.
For example, as shown in FIG. 3, the stent body is formed in a spiral shape by a frame structure 4 having an opening X. Thus, by being formed in a spiral shape, even a curved biological lumen (blood vessel or the like) can be bent along it.

The stent body has a zigzag structure by forming a continuous “<” shape as shown in FIG. 3 in which the stent body 1 a in FIG. 1 is developed. Thus, the diameter can be expanded at the time of restoration due to the zigzag structure. Further, the “<” shape is formed by the short line portion 12a and the long line portion 12b having different lengths, and the two frame structures 4a and 4b are arranged in parallel. It is formed to have a spiral shape. In this way, by forming the spiral shape with the two frame structures 4a and 4b, the angle α (FIG. 4) formed by the axial direction of the stent body 1a and the spiral direction of the frame structure becomes 1 in the spiral shape. It can be made smaller than the angle β (FIG. 5) when it is formed of a book frame structure, and the stent body 1a can be made more flexible.

Further, in FIG. 3, the two frame structures 4 a and 4 b forming the stent body 1 a are connected to each other by the central connecting portion 11 and the end connecting portion 13. The two frame structures 4a and 4b may be connected at least at two locations. For example, it is preferable that the ends of the frame structures 4a and 4b are integrally connected to each other. Thereby, since the free end is not formed, it is possible to prevent the end from damaging the inner wall of the living body lumen (blood vessel or the like). The ends are connected by a connecting portion 13. Furthermore, it is preferable that the center connection part 11 connects the bending parts of the frame structures 4a and 4b. By connecting the bent portions in this way, the connecting portions are in a crossed state, and the expansion holding force can be further increased. However, the central connection part 11 may not be provided, and it may be connected only at both ends.

In addition, there is no restriction | limiting in particular as the length of the short wire | line part 12a and the long wire | line part 12b, It can select suitably according to the biological lumen indwelled.
The number of frame structures arranged in parallel is not particularly limited and can be appropriately selected according to the purpose. The number is not limited to two, and may be about 3 to 4 Good.

-Outer diameter of stent body-
The outer diameter of the stent body is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 2.01 mm to 42 mm, more preferably 2.5 mm to 30 mm.
When the outer diameter is less than 2.01 mm, the body lumen (blood vessel or the like) may be blocked, and when it exceeds 42 mm, no larger blood vessel exists. On the other hand, if the outer diameter is within the preferred range, it is advantageous in that it can cover from the periphery to the central blood vessel, and it is more advantageous if it is within the more preferred range.

-Inner diameter of stent body-
The inner diameter of the stent body is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 2 mm to 40 mm, more preferably 2.5 mm to 20 mm.
When the inner diameter is less than 2 mm, a biological lumen (blood vessel or the like) may be blocked, and when it exceeds 40 mm, it may not be compatible with a living aorta. On the other hand, when the inner diameter is within the preferable range, it is advantageous in that it can cover peripheral blood vessels to central blood vessels, and when the inner diameter is within the more preferable range, it is further advantageous.

-Length of stent body-
The length of the stent body is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5 mm to 200 mm, more preferably 10 to 150 mm, and even more preferably 10 mm to 110 mm.
If the length is less than 5 mm, it may be difficult to align the target site, and if it exceeds 200 mm, the branch blood vessel may be blocked. On the other hand, when the length is within the preferable range, it is advantageous in that an optimum length can be selected without blocking the branch blood vessel, and when the length is within the more preferable range, it is further advantageous.

-Stent body material-
There is no restriction | limiting in particular as a material of the said stent main body, According to the objective, it can select suitably, For example, a synthetic resin, a metal, etc. are mentioned.

--- Synthetic resin--
There is no restriction | limiting in particular as said synthetic resin, According to the objective, it can select suitably, For example, polyolefin, polyester, a fluororesin etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together.
In addition, as said synthetic resin, resin which has hardness and elasticity, and biocompatible resin are preferable.
There is no restriction | limiting in particular as said polyolefin, According to the objective, it can select suitably, For example, polyethylene, a polypropylene, etc. are mentioned.
The polyester is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include polyethylene terephthalate and polybutylene terephthalate.
There is no restriction | limiting in particular as said fluororesin, According to the objective, it can select suitably, For example, polytetrafluoroethylene (PTFE), the copolymer (ETFE) of tetrafluoroethylene and ethylene, etc. are mentioned. .

--metal--
There is no restriction | limiting in particular as said metal, According to the objective, it can select suitably, For example, stainless steel, a tantalum titanium, a nickel titanium alloy, an elastic metal, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together.
Among these, an elastic metal is preferable, and a superelastic alloy is more preferable among the elastic metals.

---- Superelastic alloy ---
The superelastic alloy is generally called a shape memory alloy, and exhibits elasticity at least at a living body temperature (around 37 ° C.).
The superelastic alloy is not particularly limited and may be appropriately selected depending on the intended purpose. A Ti—Ni alloy of 49 atomic% to 53 atomic% Ni is preferable.

The buckling strength (yield stress under load) of the superelastic alloy is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 3 kg / mm ² to 20 kg / mm ² (22 ° C.). ^{, 8kg / mm 2 ~ 15kg /} mm 2 is more preferable.
When the buckling strength is less than 5 kg / mm ² , buckling may occur, and when it exceeds 20 kg / mm ² , flexibility may be lacking. On the other hand, when the buckling strength is within the preferable range, it is advantageous in terms of the balance between delivery and buckling, and when the buckling strength is within the more preferable range, it is more advantageous.

The restoring stress (yield stress during unloading) of the superelastic alloy is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 3 kg / mm ² to 180 kg / mm ² (22 ° C.). 5 kg / mm ² to 130 kg / mm ² is more preferable.

The superelasticity means that even if the metal is deformed (bent, pulled, or compressed) to a region where the normal metal is plastically deformed at the operating temperature, it is restored to its original shape without requiring heating after the deformation is released. Means that.

It is preferable that the stent body has a substantially cylindrical shape, has an opening on a peripheral surface, and each segment of the stent body has a receiving surface for holding a delivery device.

-Aperture-
The opening is not particularly limited as long as it is a gap formed between segments of adjacent stent bodies, and can be appropriately selected according to the purpose.

-segment-
The segments are not particularly limited as long as they are connected to each other so as to form an opening, and can be appropriately selected according to the purpose.
It is preferable that the segment has a line contact surface that makes line contact with the cylindrical cover or the living body lumen.
Further, as shown in FIGS. 18 and 19 (cross section along the axis of the stent 1), the segment preferably has a line contact surface 2b that makes line contact with the cylindrical cover 1b.

-Reception surface-
The receiving surface is a surface that holds the delivery device at a position where it can puncture the living body lumen from the inside to the outside of the living body lumen. Here, the “position where the living body lumen can be punctured” may be a position where the puncture member delivered by the delivery device can pierce the living body lumen, and the tip of the delivery device is the living body lumen. It may be a position where puncture is possible.
In addition, there is no restriction | limiting in particular as said delivery device, According to the objective, it can select suitably, For example, a catheter etc. are mentioned.
The receiving surface preferably includes a flat surface, may be a curved surface (for example, a curved surface recessed toward the inside of the segment), or may include both a flat surface and a curved surface.
18 and 19 (cross section along the axis of the stent 1), a straight line passing through the two end portions 2Y and 2Y ′ on the receiving surface 2a (straight line on the receiving surface 2a) and an opening X (a gap from 2X to 2Y). ) Is preferably more than 0 ° and not more than 90 °, more preferably 30 ° to 90 °, still more preferably 40 ° to 80 °, and particularly preferably 45 ° to 75 °.
If the angle A is greater than 90 °, it may come off even if it is fixed, and if it is less than 30 °, a delivery device such as a catheter may not be fixed. On the other hand, when the angle A is within the preferable range, it is advantageous in that a delivery device such as a catheter is fixed to the stent and does not come off, and is within the more preferable range, the even more preferable range, or the It is further advantageous to be within a particularly preferable range.

There is no restriction | limiting in particular as a shape in the cross section along the axis line of the stent of the said segment, According to the objective, it can select suitably, For example, a parallelogram (FIG. 18), a triangle (FIG. 19), etc. are mentioned. .

-Stent body molding method-
There is no restriction | limiting in particular as a shaping | molding method of the said stent main body, According to the objective, it can select suitably, For example, an elastic metal pipe is processed by laser processing (for example, YAG laser), electric discharge processing, chemical etching, cutting processing etc. And a method of removing a portion that becomes a communication portion.

Furthermore, it is preferable that the stent body is integrally formed by processing a superelastic metal pipe. Specifically, the stent body can be produced by removing a portion other than the portion that becomes the frame structure (segment) from the superelastic metal pipe. As a result, the stent body as a whole becomes an integrally formed product in which no sudden changes in physical properties are formed. When there is an abrupt change in physical properties, the part exhibits different deformation kinetics than other parts. Further, there is a risk that metal stress is applied to a part having different physical properties and the part is damaged. In addition, when there is a change in physical properties, the stent body is unnaturally deformed, and an unnatural flow is formed in the body fluid (blood) flow that flows through the stent body, causing restenosis.

The superelastic metal pipe used to form the stent body forms an ingot of a superelastic alloy such as a Ni-Ti alloy, and mechanically polishes the ingot, followed by hot pressing and extrusion. Manufacturing by forming a pipe with a diameter and then reducing the diameter to a pipe with a predetermined wall thickness and outer diameter by sequentially repeating the die drawing process and heat treatment process, and then chemically or physically polishing the surface. can do. Processing of the superelastic metal pipe can be performed by laser processing (for example, YAG laser), electric discharge processing, chemical etching, cutting processing, or the like, and may also be performed by using them together. In this way, the stent body produced by processing a superelastic metal pipe compares the stent body when it is expanded (dwelling and stress unloading) and when the stent body is not placed (reduced diameter). In this case, the stent body extends slightly in the axial direction of the stent body when the stent body is not placed, and there is little difference in shape and size between the two. For this reason, there is little deformation amount at the time of shape restoration in the living body, that is, there is almost no movement of the end of the stent body in the living body at the time of shape restoration. Therefore, there is little damage to the inner wall of the living body during shape restoration. Furthermore, it is preferable that the outer peripheral surface of the stent main body is chamfered with no edges. Thereby, it can prevent more reliably that a stent main body damages a biological body inner wall and a cylindrical cover.

<Cylindrical cover>
The cylindrical cover includes at least a body fluid leakage prevention material layer, and further includes a fiber layer, a porous membrane layer, and other layers as necessary.

-Body fluid leakage prevention material layer-
The body fluid leakage preventing material layer is used to puncture a puncture member from inside a living body lumen (blood vessel, etc.) into a living body lumen (blood vessel, etc.) and outside the living body lumen (blood vessel, etc.) of body fluid (blood, etc.) after puncturing. As long as it is a layer composed of a material (sealing material) that prevents leakage into the substrate, there is no particular limitation, and the layer can be appropriately selected according to the purpose.

The structure of the body fluid leakage preventing material layer is not particularly limited and may be appropriately selected depending on the purpose, and may be either a single layer structure or a multilayer structure.

The thickness of the body fluid leakage preventing material layer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.005 μm to 1 mm, more preferably 0.05 μm to 0.8 mm, and more preferably 0.1 μm. Particularly preferred is .about.0.6 mm. When the thickness is less than 0.005 μm, body fluid (blood, etc.) may leak from the material, and when it exceeds 1 mm, flexibility may not be maintained. On the other hand, if the thickness is within the preferred range, it is advantageous in terms of the balance between delivery properties and leakage (water permeability) of body fluids (blood, etc.), and within the more preferred range or within the particularly preferred range. If it is, it is further advantageous.

The sealing material is preferably a flexible and resilient resin material. Such a resin material exhibits rubber-like elasticity near room temperature, does not exhibit a clear yield in the stress-strain relationship during a tensile test, and can tolerate large deformations, and has a tensile strength of at least 100%. It is a material that quickly restores its original shape and dimensions by unloading even after deformation applying strain.
The tensile modulus of the sealing material is not particularly limited and may be appropriately selected depending on the purpose. It is preferably 0.1 MPa to 2 MPa, more preferably 0.5 MPa to 1 MPa.

There is no restriction | limiting in particular as said sealing material, According to the objective, it can select suitably, For example, an elastomer, silicone, urethane, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together.
Among these, an elastomer is preferable in that it has shape restoring property and high elasticity and can further reduce blood leakage.

--Elastomer--
There is no restriction | limiting in particular as said elastomer, According to the objective, it can select suitably, For example, a polyurethane elastomer, a fluororesin elastomer, a styrene-type elastomer, an olefin-type elastomer etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together.
Among these, styrenic elastomers are preferable in that they have shape restoring properties and high elasticity and can further reduce leakage of body fluids (blood, etc.).
There is no restriction | limiting in particular as said polyurethane elastomer, According to the objective, it can select suitably, For example, Elastollan (made by BASF), Cramiron (made by Kuraray), etc. are mentioned.
The fluororesin elastomer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include Kalrez (manufactured by DuPont) and SHIN-ETSU SIFEL (manufactured by Shin-Etsu Chemical).
There is no restriction | limiting in particular as said styrene-type elastomer, According to the objective, it can select suitably, For example, the part which consists of a part which has styrene as a main component, and butadiene and / or isoprene and / or those hydrogenated substances. The main component is a copolymer composed of
There is no restriction | limiting in particular as a commercial item of the said styrene-type elastomer, According to the objective, it can select suitably, For example, Clayton, Califlex (shell chemistry); Tufprene, Tuftec (Asahi Kasei Kogyo); Aron AR (Aron Kasei) ); Lavalon (Mitsubishi Yuka); JSR-TR, JSR-SIS, Dynalon (Nippon Synthetic Rubber); Septon (Kuraray);
The olefin-based elastomer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, polyethylene, polypropylene, a copolymer of ethylene and propylene, a copolymer of ethylene and propylene, and a third component And (alpha-olefin, diene monomer) added.
There is no restriction | limiting in particular as a commercial item of the said olefin type elastomer, According to the objective, it can select suitably, For example, a milastomer, a Tuffmer (Mitsui Petrochemical); Sumitomo TPE (Sumitomo Chemical Industries); Thermoran (Mitsubishi Yuka) );

-Fiber layer-
The fiber layer is not particularly limited as long as it is a layer composed of fibers, and can be appropriately selected according to the purpose.

The structure of the fiber layer is not particularly limited and may be appropriately selected depending on the purpose, and may be either a single layer structure or a multilayer structure.

The thickness of the fiber layer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1 mm or less, and more preferably 5 μm to 100 mm.
If the thickness is more than 1 mm, the stiffness when the stent is folded may be large. On the other hand, when the thickness is within the preferable range, it is advantageous in terms of flexible delivery, and when the thickness is within the more preferable range, it is further advantageous.

The porosity of the fiber layer is not particularly limited and may be appropriately selected depending on the purpose.

There is no restriction | limiting in particular as a knitting system of the said fiber layer, According to the objective, it can select suitably, For example, a woven knitting, a knit knitting, etc. are mentioned.
Among these, knit knitting is preferable in terms of preventing leakage fluid (bleeding) from the puncture hole, improving handling properties, and preventing fraying.

--fiber--
There is no restriction | limiting in particular as a fiber diameter of the said fiber, According to the objective, it can select suitably.

There is no restriction | limiting in particular as a material of the said fiber, According to the objective, it can select suitably, For example, polyester etc. are mentioned.
The polyester is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include polyethylene terephthalate and polybutylene terephthalate. These may be used individually by 1 type and may use 2 or more types together.

-Porous membrane layer-
The porous membrane layer is not particularly limited as long as it is a layer composed of a porous membrane, and can be appropriately selected according to the purpose.
There is no restriction | limiting in particular as thickness of the said porous membrane, Although it can select suitably according to the objective, 1 mm or less is preferable.

--- Porous membrane ---
There is no restriction | limiting in particular as a material of the said porous membrane, According to the objective, it can select suitably, For example, a fluorine resin, polyolefin, polyester, thermoplastic polyurethane, etc. are mentioned.
There is no restriction | limiting in particular as said fluororesin, According to the objective, it can select suitably, For example, PTFE, ETFE, etc. are mentioned.
There is no restriction | limiting in particular as said polyolefin, According to the objective, it can select suitably, For example, polyethylene, a polypropylene, etc. are mentioned.
The polyester is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include polyethylene terephthalate and polybutylene terephthalate.

The porosity of the porous membrane is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 25% to 80%.

The pore diameter of the fine pores of the porous membrane is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.1 μm to 10 μm.

The commercially available product of the porous membrane is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a stretching method, a solid-liquid separation method, and a beam irradiation method.

Specific examples of the porous membrane are not particularly limited and may be appropriately selected depending on the purpose. For example, PTFE-based product name Poraflon (manufactured by Sumitomo Electric Co., Ltd.), product name Microtex (Nitto Denko Corporation) Company name), the brand name Gore-Tex (manufactured by Gore-Tex Japan), and the like.

-Shape of cylindrical cover-
The shape of the cylindrical cover is not particularly limited as long as it is cylindrical, and can be appropriately selected according to the purpose.

-Structure of the cylindrical cover-
There is no restriction | limiting in particular as a structure of the said cylindrical cover, Although it can select suitably according to the objective, A 3 layer structure is preferable.
The three-layer structure is not particularly limited and may be appropriately selected depending on the intended purpose. The inner layer and the outer layer, which are polyester fiber layers, and the middle layer, which is an elastomer layer formed between the inner layer and the outer layer, can be selected. A structure consisting of layers is preferred.
By making the cylindrical cover have such a three-layer structure, handling properties can be improved, and leakage of body fluid (blood, etc.) to the outside of a biological lumen (blood vessel, etc.) can be more sufficiently reduced. it can.
By making the intermediate layer an elastomer layer, leakage of body fluid (blood, etc.) to the outside of a living body lumen (blood vessel, etc.) can be sufficiently reduced, and adhesion between the inner layer and the outer layer is improved. You can also Further, when the intermediate layer is an elastomer layer, it is not necessary to use biological proteins such as gelatin, collagen, bovine albumin and the like, and the occurrence of abnormal heat generation can be suppressed.
Further, the inner layer may be crimped, and in this case, tissue healing can be improved. Further, the outer layer may be subjected to an expansion-resistant treatment. In this case, even if the outer layer is made of knitted fibers, the same degree of expansion as that of woven fibers can be obtained.
If there is at least one elastomer layer between the stent body and the living body lumen (cerebral blood vessel or the like), body fluid (blood or the like) will not leak even if the living body lumen (brain blood vessel or the like) is punctured with a needle.

-Thickness of cylindrical cover-
The thickness of the cylindrical cover (body fluid leakage prevention material layer) is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.005 mm to 1 mm, more preferably 0.05 mm to 0.8 mm. Preferably, 0.1 mm to 0.6 mm is particularly preferable. If the thickness is less than 0.005 mm, body fluid (blood, etc.) may leak from the material, and if it exceeds 1 mm, flexibility may not be maintained. On the other hand, when the thickness is within the preferred range, it is advantageous in terms of the balance between delivery properties and leakage (water permeability) of body fluids (blood, etc.), and within the more preferred range or within the particularly preferred range. If it is, it is further advantageous.

<Arrangement of stent body and cylindrical cover>
The outer peripheral surface and inner peripheral surface of the stent main body may be covered with a cylindrical cover, and the stent main body may be embedded in the cylindrical cover. Either one may be covered with a cylindrical cover. That is, the cylindrical cover is formed on the outer side or inner side of the substantially cylindrical shape formed by the stent main body so as to cover the peripheral surface (outer peripheral surface, inner peripheral surface, or outer peripheral surface and inner peripheral surface) of the stent main body. To position. Here, when either one of the outer peripheral surface and the inner peripheral surface of the stent main body is covered with a cylindrical cover, the stent main body and the cylindrical cover are bonded with, for example, a known adhesive. Done with.
As for the said stent main body, the whole surrounding surface may be coat | covered with the cylindrical cover, and only a part (for example, center part) of the surrounding surface may be coat | covered with the cylindrical cover.
The said cylindrical cover may be arrange | positioned so that a stent main body may be contacted, and the other member may be interposed between the stent main body and the cylindrical cover.

<Other members>
There is no restriction | limiting in particular as said other member, According to the objective, it can select suitably, For example, an X-ray contrast marker etc. are mentioned.

<Manufacturing method of covered stent>
A method for manufacturing a covered stent of the present invention, particularly, a method for forming a cylindrical cover will be described.
When the cylindrical cover has a multilayer structure, for example, by fixing the stent body to the outer surface of the first layer film (inner layer), the outer surface is coated with a castable resin (for example, dipping). It can be performed by forming a second layer film on the outside of the first layer film. In this case, it is preferable to temporarily fix the stent body on the first layer film before forming the second layer film (outer layer). This temporary fixing may be performed with an adhesive.

Moreover, the manufacturing method of the covered stent in which the cylindrical cover is formed only inside the stent body is as follows.
First, the stent body is dipped in an immersion liquid in which the same material as the outermost layer of the cylindrical cover is dissolved in a solvent. Before the immersion liquid coated on the stent body dries, the stent body is pressed against the outermost layer of the cylindrical cover to be crimped. Thereby, a covered stent (for example, FIG. 13 described later) in which a cylindrical cover is formed only inside the stent body is formed.

Moreover, the manufacturing method of the covered stent in which the cylindrical cover is formed only on the outer side of the stent body is as follows.
First, the stent body is dipped in an immersion liquid in which the same material as the innermost layer of the cylindrical cover is dissolved in a solvent. Before the immersion liquid coated on the stent body dries, the stent body is pressed against the innermost layer of the cylindrical cover to be crimped. Thereby, a covered stent (for example, FIG. 12 described later) in which a cylindrical cover is formed only on the outer side of the stent body is formed.

Further, the formation of the cylindrical cover is not limited to the case of using a film body that has been formed in advance. For example, the cylindrical cover may be formed using a resin solution capable of forming a film. Specifically, a liquid material in which an elastomer such as a polyurethane elastomer or a fluororesin elastomer is dissolved in a solvent is prepared, and the stent body is sealed by immersing and lifting the stent body in this liquid material and volatilizing the solvent. A film-like material can be formed. In addition, you may repeat the immersion of the stent main body in said liquid substance, pulling up, and the volatilization of a solvent.
There is no restriction | limiting in particular as said liquid substance, According to the objective, it can select suitably, For example, the THF (tetrahydroxy furan) solution of a polyurethane elastomer, the DMF (dimethylformaldehyde) solution of a fluororesin elastomer, etc. are mentioned. It is done.

<Covered stent delivery method>
There is no restriction | limiting in particular as a delivery method of the said covered stent, According to the objective, it can select suitably, For example, the method of delivering via biological lumens, such as a blood vessel, using a delivery device etc. are mentioned.

-Delivery device-
There is no restriction | limiting in particular as long as it is a device which can deliver a covered stent as said delivery device, According to the objective, it can select suitably, For example, a catheter etc. are mentioned.

--catheter--
The catheter is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a blood vessel catheter having a diameter of 1 French to 25 French.

Hereinafter, embodiments of the covered stent of the present invention will be described with reference to the drawings.

<First Embodiment>
The first embodiment will be described below.
6 to 9 are explanatory views showing an example of a method for using the covered stent according to the first embodiment of the present invention.

First, (i) a sheath is inserted into a blood vessel, and (ii) a treatment guide wire (not shown) and a microcatheter are brought through the sheath to a cerebral blood vessel near the lesion. (Iii) Next, the stent delivery system is advanced along the preceding treatment guide wire so that the stent delivery system in which the covered stent (stent graft) is contained in the mantle passes through the microcatheter, and is advanced near the lesioned part. To stop. Further, the covered stent (stent graft) is released by pulling the mantle containing the covered stent (stent graft) or by pushing out the covered stent (stent graft). As a result, as shown in FIG. 6, the covered stent (stent graft) 1 is delivered and placed in the cerebral blood vessel 3 in the vicinity of the lesioned part 102 that generates the abnormal electrical signal 101. After the covered stent (stent graft) 1 is indwelled, the treatment guide wire and the stent delivery system are pulled out, and the microcatheter is maintained without being pulled out.
Here, in the above-described procedure, after bringing the treatment guide wire and the microcatheter to the cerebral blood vessels near the lesioned part, the stent delivery system is advanced so that the stent delivery system passes through the microcatheter, and the covered stent ( After the stent graft (1) is opened and placed, the treatment guide wire and stent delivery system are withdrawn and the microcatheter is kept without being pulled out. Instead, only the treatment guide wire is moved to the cerebral blood vessels near the lesion. Then, the covered stent (stent graft) is advanced along the preceding treatment guide wire by the stent delivery system, and the covered stent (stent graft) 1 is opened and placed, and then the treatment guide wire is left and left. Only pull the door delivery system, along the therapeutic guidewire may be inserted microcatheter.
At this time, instead of a microcatheter, a guiding catheter may be used to deliver the above-described procedure and a therapeutic device described later. In addition, the above-described procedure and the treatment device described later may be delivered without using a microcatheter or a guiding catheter.

Here, the covered stent 1 (stent graft) has, for example, a substantially cylindrical shape (formed in a substantially cylindrical shape) as shown in FIG. 1, and a stent main body 1a having an opening X on the peripheral surface, and a stent main body 1a. It has a cylindrical cover 1b that covers a part (center portion) of the peripheral surface.

As shown in FIG. 3, the stent main body 1 a is in a state where the two frame structures 4 a and 4 b forming the stent main body 1 a are connected by the central connecting portion 11 and the end connecting portion 13, respectively.

Further, as shown in FIG. 18, the stent body 1a has a receiving surface for holding the catheter 5 at a position where each segment 2 of the stent body 1a can puncture the cylindrical cover 1b from the inside of the cerebral blood vessel 3 to the outside. 2a. Here, in the cross section along the axis of the stent 1, the angle A formed by the straight line by the plane on the receiving surface 2a (the straight line passing through the two end portions 2Y and 2Y ′ on the receiving surface 2a) and the straight line by the opening X is 60 °.
Moreover, the shape of each segment 2 of the stent body 1a is a parallelogram.

Here, as shown in FIG. 10, the cylindrical cover 1b in the stent 1 includes a polyester fiber layer 14 as an inner layer provided on the inner peripheral surface of the stent main body 1a, and an outer layer provided on the outer peripheral surface of the stent main body 1a. Polyester fiber layer 15 as a polyester fiber layer 14, 15 is a cylindrical body. Furthermore, the cylindrical cover 1b has an elastomer layer (intermediate layer) 16 that exists between the polyester fiber layer 14 and the polyester fiber layer 15 and between the polyester fiber layers 14 and 15 and the stent body 1a. Furthermore, the stent body 1 a is sandwiched between the polyester fiber layer 14 and the polyester fiber layer 15, and the two polyester fiber layers 14 and 15 are fixed by the elastomer layer 16.
Here, the polyester fiber layers 14 and 15 are fiber structures obtained by knitting, weaving, and assembling a joint type composite fiber obtained by simultaneously spinning polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), and an elastomer. The layer 16 is a layer composed of a polystyrene-based elastomer. If there is at least one elastomer layer 16 between the stent body 1a and the cerebral blood vessel 3, blood will not leak even if the cerebral blood vessel 3 is pierced with a needle.

(Iv) Next, as shown in FIG. 7, the tip 5a of the microcatheter 5 is bent in the direction of the lesion 2 and fixed. (V) Push in a delivery device A (for example, MyClass microcoil delivery system manufactured by Johnson & Johnson Co., Ltd.) provided with a treatment device 9 having a needle-like stimulus imparting member 7 and a fixing member 8 at the tip. As a result, the treatment device 9 is pushed through the lumen of the microcatheter 5 and passes through the tip 5 a of the microcatheter 5. Thereby, the needle-like stimulus imparting member 7 in the treatment device 9 penetrates the blood vessel wall 3a by piercing the tubular cover 1b of the covered stent 1 and the blood vessel wall 3a of the cerebral blood vessel 3. After that, as shown in FIG. 8, at least a part of the needle-like stimulus imparting member 7 is located in the vicinity of the lesioned part 102, and one member 8 a of the two members of the fixing member 8 is outside the cerebral blood vessel 3. The treatment device 9 is disposed such that the other member 8b of the fixing member 8 is located inside the cerebral blood vessel 3, the treatment device 9 is disconnected from the delivery device A by an electric current, and the treatment device 9 is placed. Pull out delivery device A. (Vi) Thereafter, the microcatheter 5 is pulled out. Here, as described above, since the cylindrical cover 1b of the covered stent 1 is made of a highly elastic elastomer material having a shape restoring property for the elastomer layer 16, it is needle-shaped from the inside of the cerebral blood vessel 3. Even when the stimulus applying member 7 is punctured into the cerebral blood vessel 3, blood does not leak.

Next, as shown in FIG. 9, the stimulus applying member is expanded so that one member 8 a of the fixing member 8 and the other member 8 b of the fixing member 8 sandwich the blood vessel wall 3 a of the cerebral blood vessel 3. 7 is fixed to the cerebral blood vessel 3.

As described above, the fixing member 8 fixes the stimulus applying member 7 to the cerebral blood vessel 3 so that the stimulus applying member 7 can be placed in the vicinity of the lesioned part 102. As a result, the stimulus applying member 7 is continuously swung by the pulsation of the cerebral blood vessel 3, and the mechanical stimulation can be continuously applied to the lesioned portion 102, thereby realizing a treatment for a cranial nerve disease with a low degree of invasiveness. can do.

In the first embodiment described above, the covered stent 1 is placed in the cerebral blood vessel 3. However, the present invention is not limited to this, and other biological lumens such as other blood vessels, bile ducts, esophagus, trachea, urethra, and the like. You may detain it.

In the first embodiment described above, as shown in FIG. 18, the angle A formed by the straight line by the plane on the receiving surface 2a and the straight line by the opening X (gap from 2X to 2Y) is 60 °. It is not limited to this.

In the first embodiment described above, as shown in FIG. 18, the shape of the segment 2 of the stent body 1a in the cross section along the axis of the stent 1 is a parallelogram, but is not limited thereto. For example, it may be another quadrangle such as a rectangle, a triangle, or the like.

In the first embodiment described above, as shown in FIG. 1, the covered stent 1 in which only the central portion of the peripheral surface of the stent body 1a is covered with the cylindrical cover 1b is used, but the present invention is not limited to this. For example, as shown in FIG. 11, a covered stent in which the entire peripheral surface of the stent body 1a is covered with a cylindrical cover 1b may be used.

In the first embodiment described above, both the outer peripheral surface and the inner peripheral surface of the stent body 1a are covered with the cylindrical cover 1b. However, the present invention is not limited to this. For example, FIGS. As shown, either one of the outer peripheral surface and the inner peripheral surface of the stent body 1a may be covered with a cylindrical cover 1b.

In the first embodiment described above, the covered stent 1 is placed by using the microcatheter 5 and further the treatment device 9 is placed. However, the present invention is not limited to this, and the guiding catheter is not limited thereto. May be used. In that case, the covered stent 1 and the treatment device 9 may be placed only with the guiding catheter, or the microcatheter 5 may be fed through the lumen of the guiding catheter GC as shown in FIG. By feeding the microcatheter 5 through the lumen of the guiding catheter GC, the guide wire with needle or the needle-like stimulus applying member 7 is assisted to puncture the cylindrical cover 1b and the blood vessel wall 3a, or the stimulus applying member. 7 can assist the passage of the spiral body 7 through the cylindrical cover 1b and the blood vessel wall 3a.
Further, when the covered stent (stent graft) 1 is delivered to the lesioned part 102, the microcatheter 5 and the guiding catheter GC need not be used.

In the first embodiment described above, the needle-like stimulus imparting member 7 is punctured into the cylindrical cover 1b of the covered stent 1 and the blood vessel wall 3a of the cerebral blood vessel 3. However, the present invention is not limited to this. The tip 5a of the microcatheter 5 or the tip of the guiding catheter may be punctured into the cylindrical cover 1b and the blood vessel wall 3a.

In the first embodiment described above, a needle-like stimulus imparting member that imparts mechanical stimulus is used as the stimulus imparting member 7 in the treatment device 9, but the present invention is not limited to this, and the needle-like stimulus imparting member is not limited thereto. Alternatively, a spiral body (FIGS. 15 and 16 to be described later) and a ring for applying mechanical stimulation, an electrode for applying electrical stimulation, a heat source and a cooling source for applying thermal stimulation, and the like can be used.

In the first embodiment described above, the stimulus applying member 7 is fixed to the blood vessel wall 3a of the cerebral blood vessel 3 by the fixing member 8. However, the present invention is not limited to this.

In the first embodiment described above, the microcatheter 5 is used as a delivery device for delivering the stimulus applying member 7, but the present invention is not limited to this, and other delivery devices such as a guiding catheter and a cannula are used. It may be used.

<Second Embodiment>
The second embodiment will be described below with a focus on differences from the first embodiment. In addition, the same code | symbol is attached | subjected to the site | part which has the same function and structure as 1st Embodiment.
15 to 16 are explanatory views showing an example of a method of using the treatment device according to the second embodiment of the present invention.

In the second embodiment, after (i) to (iii) in the first embodiment, (iv) the tip 5a of the microcatheter 5 is bent toward the lesioned part 102 and fixed. (V) A guide wire with a needle is advanced through the lumen of the microcatheter 5 to pass the tip 5a of the microcatheter 5. Thereby, the guide wire with a needle pierces the tubular cover 1b of the covered stent 1 and the blood vessel wall 3a of the cerebral blood vessel 3, and penetrates the blood vessel wall 3a. Thereafter, the tip 5a of the microcatheter 5 is advanced to the outside of the cerebral blood vessel 3 along the guide wire with needle, and the guide wire with needle is pulled out. (Vi) Thereafter, as shown in FIG. 15, a delivery device A (for example, manufactured by Johnson & Johnson Co., Ltd.) provided with a treatment device 9 having a spiral body as the stimulus applying member 7 and a fixing member 8 at the tip. By pushing in the my class microcoil delivery system), the treatment device 9 is pushed through the lumen of the microcatheter 5 to pass through the tip 5a of the microcatheter 5, and at least a part of the stimulus applying member 7 The treatment device 9 is positioned in the vicinity so that one of the two members 8 a of the fixing member 8 is positioned outside the cerebral blood vessel 3 and the other member 8 b of the fixing member 8 is positioned inside the cerebral blood vessel 3. The treatment device 9 is disconnected from the delivery device A by an electric current, and the treatment device 9 is left in place. I pulled out a scan A. (Vii) Thereafter, the microcatheter 5 is pulled out. Next, as shown in FIG. 16, the stimulating member is expanded so that one member 8 a of the fixing member 8 and the other fixing member 8 b of the fixing member 8 sandwich the blood vessel wall 3 a of the cerebral blood vessel 3. 7 is fixed to the blood vessel wall 3a. Here, as described above, the cylindrical cover 1b of the covered stent 1 is made of a highly elastic elastomer material having a shape restoring property for the elastomer layer 16, so that the guide with needle from the inside of the cerebral blood vessel 3 is used. Even if the wire is punctured into the cerebral blood vessel 3 and the microcatheter 5 is advanced to the outside of the cerebral blood vessel 3, blood does not leak.
In the second embodiment, the needle guide wire is inserted into the cylindrical cover 1b of the covered stent 1 and the blood vessel wall 3a of the cerebral blood vessel 3 to penetrate the blood vessel wall 3a, and then the microcatheter 5 is attached to the needle. The guide wire with needle is pulled out along the guide wire to the outside of the cerebral blood vessel 3, but the guide wire with needle is not limited to this, and the guide wire with needle is connected to the cylindrical cover 1b of the covered stent 1 and the cerebral blood vessel. 3 is inserted into the blood vessel wall 3a to penetrate the blood vessel wall 3a to form a minute hole as a passage, and then the guide wire with needle is pulled out without allowing the microcatheter 5 to enter the outside of the brain blood vessel 3. Alternatively, the treatment device 9 may be passed through the cylindrical cover 1b and the minute holes formed in the blood vessel wall 3a of the cerebral blood vessel 3 as a passage.

The covered stent of the present invention is placed in a living body lumen (particularly, a blood vessel such as a cerebral blood vessel) to puncture a puncture member from the living body lumen into the living body lumen while ensuring the lumen space of the living body lumen. Even in this case, leakage of body fluids outside the body lumen can be sufficiently reduced, so that it can be suitably used for the treatment of diseases (especially cranial nerve diseases such as epilepsy, Parkinson's disease, trigeminal neuralgia). is there.

1 Covered stent (stent graft)
DESCRIPTION OF SYMBOLS 1a Stent body 1b Tubular cover 2 Segment 2a Receiving surface 2b Line contact surface 3 Blood vessel 3a Blood vessel wall 4 Frame structure 4a Frame structure 4b Frame structure 5 Microcatheter 5a Microcatheter tip 7 Stimulation member 8 Fixing member 8a Member 8b member 9 treatment device 11 central connecting part 12a short line part 12b long line part 13 terminal connecting part 14 polyester fiber layer 15 polyester fiber layer 16 elastomer layer (intermediate layer)
101 abnormal electric signal 102 lesion X X opening 2X, 2X ′ end 2Y, 2Y ′ end A delivery device GC guiding catheter

Claims (12)

1. A stent body having a substantially cylindrical shape and having an opening on a peripheral surface;
   A covered stent that can be placed in a living body lumen including a cylindrical cover that covers at least a part of the peripheral surface of the stent body,
   The cylindrical cover includes a layer made of a material that prevents leakage of body fluid to the outside of the living body lumen when the living body lumen is punctured from the inside of the living body lumen and after the puncturing. Stent.
2. The covered stent according to claim 1, wherein the material for preventing leakage of the body fluid to the outside of the living body lumen is an elastomer.
3. The covered stent according to claim 2, wherein the cylindrical cover is made of only an elastomer layer.
4. The covered stent according to claim 3, wherein the elastomer layer is at least one layer.
5. The covered stent according to claim 1, wherein the cylindrical cover includes an inner layer, an outer layer, and an intermediate layer provided between the inner layer and the outer layer.
6. The inner layer and the outer layer are layers of polyester fibers,
   The covered stent according to claim 5, wherein the intermediate layer is a layer made of a material that prevents leakage of the body fluid to the outside of the living body lumen.
7. The covered stent according to claim 1, wherein the stent body has a receiving surface for holding a delivery device at a position where the living body lumen can be punctured from the inside to the outside of the living body lumen.
8. In a cross section along the axis of the covered stent,
   The stent body is in line contact with the cylindrical cover or the biological lumen;
   The covered stent according to claim 7, wherein an angle formed by a straight line passing through two end portions of the receiving surface and a straight line formed by the opening is greater than 0 ° and equal to or less than 90 °.
9. In a cross section along the axis of the covered stent,
   The covered stent according to claim 8, wherein an angle formed by a straight line passing through two ends of the receiving surface and a straight line by the opening is 30 ° to 90 °.
10. The covered stent according to claim 7, wherein the receiving surface includes a flat surface.
11. The covered stent according to claim 7, wherein the receiving surface includes a curved surface.
12. The covered stent according to claim 7, wherein the delivery device is a catheter.

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