JPH10211287A - Stent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a back flow and prevent the development of complication by forming a stent into a cylindrical shape so as to have the elasticity and suspending a film body, which is formed of a flexible material and acts as a check-valve, from its part. SOLUTION: A stent main body 1 is constituted by forming a metal (including shape memory alloy) net body into a cylinder. An English knot net body is used for it. The surface of a material having a lot of small holes bored in its Teflon-based super-thin film is coated, rolled into a pipe, and formed into a film body 2. This is inserted in the stent main body 1 and the bottom end of the film body 2 is suspended longer than the stent main body 1 so as to be formed into a suspension part 2a. The top end is folded up and stacked with the edge of the top opening of the stent main body 1. The suspension part 2a of this film body 2 is functioned as a check-valve so as to prevent the development of complication such as the reflux esophagitis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stent, and more particularly to an improvement in a stent used as one of treatment means for stenotic lesion of a luminal organ.

[0002]

BACKGROUND OF THE INVENTION Recently, EMS (Expandable Metallic) has been used as a permanent treatment for stenotic lesions such as carcinogenesis in luminal organs and luminal organs of the digestive system.
Stent) has spread and good clinical results have been reported. The stent used here is a metal or shape memory alloy net made into a cylindrical shape, or a plastic cylinder, which is forcibly expanding a stenosis state by placing it in a lesion. is there.

[0003]

However, the above-mentioned conventional stent may cause unexpected complications depending on the place where the stent is placed. For example, in the placement of lower esophageal stenosis or cardia cancer, gastric acid and gastric acid Reflux of the contents occurred, which caused reflux esophagitis, nausea and vomiting, and was often difficult to treat.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made by focusing on the actual situation and problems of the above-mentioned conventional stent. The present invention solves such problems and prevents reflux regardless of the place where the stent is placed. It is an object of the present invention to provide a stent having a novel structure capable of preventing the occurrence of complications such as the above.

[0005]

In order to achieve this object, a stent according to the present invention has elasticity, and a backflow formed of a flexible material is formed on a part of a substantially cylindrical stent body. The film body acting as a check valve is vertically provided, wherein the stent body is formed of a metal net, and the stent body is formed of a shape memory alloy, The stent body is formed of plastic, the film body is a Teflon-based ultra-thin film having a number of small holes perforated at least for surface processing, and the film body is polyurethane. That the membrane is made of latex, that the hanging portion of the membrane is made outside the lower end of the stent body, and that the hanging portion of the membrane is made of It is characterized in that is made in the stent body.

[0006]

According to this structure, the membrane suspended from the stent body acts as a check valve due to its flexibility, and blocks the passage of the backflow when backflow is to occur. This will stop the operation and prevent the occurrence of complications due to the reflux.

[0007]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a stent embodying the present invention, and FIG. 2 is a perspective view of an essential part showing an operating state of the membrane.

In these figures, reference numeral 1 denotes a stent body. This stent main body is formed of a metal (including a shape memory alloy) net body, which is also formed by frog crotch netting into a substantially cylindrical shape.

Although this embodiment shows a cylindrical stent body which is formed by frog-groove knitting with a metal net, the present invention is not limited to this material as described in the claims. It can also be achieved by using other plastics and the like, and is not limited to the method of knitting and the like, and is intended to be at least one that is cylindrical when fully expanded.

[0010] Further, in the figure, reference numeral 2 denotes a film body, and the surface of the material is coated with an ultra-thin Teflon-based thin film having a number of small holes (trade name: Gore-Tex). It is a flexible material molded by itself or itself and rolled into a pipe shape.

In addition to the film material shown in this embodiment, it is needless to say that any other flexible material such as polyurethane or latex can be used.

The membrane 2 is inserted into the stent main body 1 and has a lower end vertically extending from the stent main body 1 to form a vertical portion 2a. The upper end is folded back to form the stent main body 1. Is overlapped with the upper opening edge.

The state of attachment of the membrane 2 is not only shown in the drawing, but also by shortening the length of the membrane 2 and stopping its upper end in the middle of the stent body 1, and attaching it to the lower end of the stent body 1. The hanging portion 2a may be formed, or the film body 2 formed shorter than the stent body 1 may be fixed to the upper end thereof in the stent body 1, and the hanging portion 2a may be located in the stent body 1. .

The membrane 2 is joined by nylon threads 3a and 3b at the stent main body 1 and its folded portion, that is, the upper opening edge of the stent main body 1 and the lower end edge of the stent main body 1, so as to be integrated.

Further, the fastening structure also includes a nylon yarn 3a,
In addition to bonding using 3b or the like, it is also possible to use an adhesive or a method such as fusion depending on the material.

Further, in the present embodiment, two texas 4 for insertion are inserted into the rolled film body 2 described above.
a, 4b are inserted, and the tips of the teeth 4a, 4b are entangled at positions facing the lower opening edge of the film body 2. Of course, other insertion means can be used instead of the teeth 4a, 4b.

The stent according to the present embodiment is configured as described above. Note that the positional relationship between the stent body 1 and the membrane body 2 may be such that the vertical portion 2a of the membrane body 2 is formed in a part of the stent body 1, and the membrane body 2 may be attached to the outside of the stent body 1, or Various application changes are possible, such as disposing the upper end of the membrane 2 near the lower end of the stent main body 1 or positioning the upper end of the membrane 2 in the stent main body 1. What is necessary is just to act as a check valve.

Here, the method of using the stent will be described assuming the case of lower esophageal cancer. The method of indwelling differs depending on the configuration of the stent, but in the embodiment shown in FIG. The stent body 1 is indwelled in front of the stenosis portion by using this, and the membrane 2 is indwelled from the anal side into the stomach. Next, the second stent is placed in the form of being inserted into the already placed stent.At this time, the upper end is located closer to the oral cavity than the first stent, and the lower end is slightly inserted into the stomach from the esophagus-stomach connection. Place it where it is. As a result, the lesion is covered with the membrane 2, and the vertical portion 2a of the membrane 2 is placed in the stomach.

The vertical portion 2a placed in the stomach prevents the contents of the stomach from flowing back. In addition, depending on the structure of the stent, the placement position of the hanging portion 2a may be different, but the backflow preventing action by the hanging portion 2a is equivalent.

[0020]

The stent according to the present invention is constructed and used as described above. Therefore, in addition to preventing reflux of gastric contents, which has been regarded as a problem in the past, it is also possible to suppress tumor growth in the stent and eliminate dysphagia, thereby improving the efficiency of treatment. Can be.

[Brief description of the drawings]

FIG. 1 is a perspective view of a stent embodying the present invention.

FIG. 2 is an essential part perspective view showing an operation state of a film body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stent main body 2 Membrane body 2a Hanging part 3a Nylon thread 3b Nylon thread 4a Tegs 4b Tegs

Claims (9)

[Claims] The present invention is characterized in that a membrane body having elasticity and acting as a check valve, which is formed of a flexible material, is provided vertically on a part of a substantially cylindrical stent body. Stent. 2. The stent according to claim 1, wherein the stent main body is formed of a metal net. 3. The stent according to claim 1, wherein the main body of the stent is formed of a shape memory alloy. 4. The stent according to claim 1, wherein the stent body is formed of plastic. 5. The film body according to claim 1, wherein an ultra-thin Teflon-based thin film having a number of small holes formed therein is used for at least surface processing.
Alternatively, the stent according to claim 4. 6. The stent according to claim 1, wherein said membrane is made of polyurethane. 7. The stent according to claim 1, wherein said membrane is made of latex. 8. The stent according to claim 1, wherein the vertical portion of the membrane is formed outside the lower end of the stent body.
The stent according to claim 2, claim 3, claim 4, claim 5, claim 6, or claim 7. 9. The stent according to claim 1, wherein the vertical portion of the membrane is formed in the stent main body. The stent according to claim 7.