A covered stent

Abstract

The utility model discloses a kind of film-covered stents, belong to medical instrument technical field.It includes: stent body, with self-expanding structure, stent body proximal end is connected with the delivery guide wire that can be mechanically or electrolytically released, for adjusting release after being in position;Film layer covers the whole area or partial area of stent body;Film layer and stent body are fixedly connected.Film layer both ends contain the marker point of X-ray impermeable, to indicate the relative position of film layer in operation.The utility model proposes two kinds of stents of whole film covering and local film covering, suitable film length can be selected for different length of pathological changes, thereby reducing the influence of film on perforating vessel, the utility model further increases the film layer of coiling structure, which can further reduce the delivery resistance of film-covered stent.

Description

Technical Field

[0001] This utility model belongs to the field of medical device technology, specifically relating to a covered stent. Background Technology

[0002] Minimally invasive interventional surgery is a common treatment for intracranial aneurysms. Currently, commonly used techniques for treating intracranial aneurysms include coil embolization, stent-assisted coil embolization, flow diverter placement, and covered stent implantation. For large and giant saccular aneurysms, wide-necked aneurysms, fusiform aneurysms, and dissecting aneurysms, the use of traditional coil or stent-assisted coil embolization techniques can lead to prolonged intraoperative time, incomplete aneurysm occlusion, and a high postoperative complication rate. Flow diverters, due to their high braid density, may also have issues with incomplete apposition to the aneurysm wall and flexibility, which can affect the postoperative aneurysm occlusion rate and the occurrence of ischemic complications.

[0003] Covered stents can address the issue of incomplete aneurysm occlusion to some extent. By completely blocking blood flow into the aneurysm cavity, they can achieve immediate and complete aneurysm healing. Covered stents can also be used to treat intracranial arteriovenous fistulas or repair vascular defects caused by trauma. Therefore, covered stents, as an endovascular stent, have enormous clinical application potential. However, existing covered stents suffer from a series of problems, including delivery difficulties, stent endoleak, poor compliance, and a tendency to cause perforator occlusion. These problems significantly limit the clinical application prospects of covered stents, resulting in very limited clinical use.

[0004] To address these shortcomings, this invention proposes a novel film-coated stent to solve the aforementioned problems. Utility Model Content

[0005] This invention provides a covered stent, which aims to reduce the impact of the covering on perforating vessels and further reduce the delivery resistance of the covered stent.

[0006] This utility model provides a film-coated stent, the technical solution of which is as follows: The stent body has a self-expanding structure, and the proximal end of the stent body is connected to an electrically detachable delivery guide wire for release after adjustment into place; A coating layer that covers all or part of the main body of the support structure; The coating layer and the support body are fixedly connected.

[0007] Furthermore, when the covering layer covers the entire area of ​​the stent body, it is used for aneurysms with a wide neck.

[0008] Furthermore, when the covering layer covers a portion of the stent body, it is used for aneurysms with narrow necks or aneurysms with many branches of the parent artery.

[0009] Furthermore, the main body of the support is made of nickel-titanium alloy, the length of the main body is in the range of 10~70mm, and the outer diameter is in the range of 1.5~10mm; the outer diameter of the main body is less than or equal to the inner diameter of the support coating layer.

[0010] Furthermore, the support body and the coating layer are fixedly connected by any one of the following processes: bonding, welding, or sewing.

[0011] Furthermore, the end of the stent body contains radiopaque markings; both ends of the coating layer contain radiopaque markings.

[0012] Furthermore, the main body of the support is a rolled structure, and the coating layer is a rolled or continuous structure.

[0013] Furthermore, the coating layer is made of at least one polymer material selected from expanded polytetrafluoroethylene, PU, ​​or PET.

[0014] Furthermore, the thickness of the polymer film in the coating layer is 5 micrometers to 100 micrometers.

[0015] Furthermore, the material of the developing markers can be composed of one or more materials such as platinum, platinum-iridium, and platinum-tungsten.

[0016] The beneficial effects of this utility model are: 1. The proximal end of the support body of this utility model is connected to a delivery guide wire that can be mechanically or electrically released, and the support body can be completely released after being adjusted into place.

[0017] 2. In this utility model, when the main body of the stent is a rolled structure and the covering layer is a continuous structure, it can effectively block the aneurysm without worrying about endoleak.

[0018] 3. In this utility model, when the main body of the stent is a rolled structure and the coating layer is also a rolled structure, the stent and the coating layer can be rolled up simultaneously during delivery in the conduit, thus the stent has lower delivery resistance.

[0019] 4. Marking points are set at both ends of the stent body and the covered layer to form a clear three-dimensional positioning reference under X-ray fluoroscopy, which makes it easier for the surgeon to judge the stent position in real time. Especially in areas where blood vessels overlap or are tortuous, it significantly improves positioning accuracy and reduces surgical risks caused by positional deviations. Attached Figure Description

[0020] For ease of explanation, this utility model is described in detail below with reference to specific embodiments and accompanying drawings.

[0021] Figure 1 This is a schematic diagram of the structure of a partially coated support of this utility model, wherein both the support end and the film end contain developing marks. Figure 2 This is a side view of a partially coated support of this utility model, with development markings at both the support end and the film end. Figure 3 This is a top view of part of the film-coated support of this utility model; Figure 4 This is a schematic diagram of the overall film-coated support structure of this utility model; Figure 5 This is a side view of the integral film-coated support of this utility model. Figure 6 This is a top view of the integral film-coated support of this utility model; Figure 7 This is a schematic diagram of the structure of the present invention, in which both the coating layer and the main support body are curled structures; Figure 8 This is a top view of the coating layer and the main support body of this utility model, both of which have a rolled structure.

[0022] Figure 9 This is a schematic diagram of the connection between the film-coated support and the delivery guide wire of this utility model.

[0023] In the diagram: 1. Support body; 2. Coating layer; 3. Transport guide wire; 4. Development marker point. Detailed Implementation

[0024] The following are specific embodiments of the present invention described in conjunction with the accompanying drawings, further illustrating the technical solution of the present invention. However, the present invention is not limited to these embodiments. Specific details such as particular configurations and components are provided in the following description merely to aid in a comprehensive understanding of the embodiments of the present invention. Therefore, those skilled in the art should understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Furthermore, for clarity and brevity, descriptions of known functions and structures have been omitted.

[0025] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0026] like Figures 1 to 9 A specific embodiment of a film-coated support is shown, in which a metal tube is cut into a hollow structure using a laser and then heat-treated to shape it into a support body 1 of the required size. Subsequently, a film layer 2 is wrapped around the surface of the support body 1 and the two are fixed together by means of bonding, welding or sewing.

[0027] Specifically, the stent body 1 is made of nickel-titanium alloy laser cutting into a self-expanding tubular structure. The proximal end of the stent body 1 is connected to a delivery guide wire 3 that can be mechanically or electrically released, for release after adjustment. Specifically, the self-expanding structural support body 1 and the mechanically or electrically detachable delivery guide wire 3 are existing mature technologies, and will not be elaborated here.

[0028] Specifically, the coating layer 2 covers all or part of the area of ​​the support body 1, and the coating layer 2 is made of at least one polymer material selected from expanded polytetrafluoroethylene, PU or PET.

[0029] Specifically, the thickness of the polymer film in the coating layer 2 is 5 micrometers to 100 micrometers.

[0030] Specifically, the two ends of the overlay layer 2 and the end of the stent body 1 contain radiopaque markers 4, which form a clear three-dimensional positioning reference under X-ray fluoroscopy. This facilitates the surgeon to judge the stent position in real time, especially in areas where blood vessels overlap or are tortuous, significantly improving positioning accuracy and reducing surgical risks caused by positional deviations.

[0031] Specifically, the material of the developing marker 4 can be one or more of platinum, platinum-iridium, and platinum-tungsten.

[0032] Specifically, the radiopaque markers 4 at both ends of the coating layer 2 are uniformly distributed in the circumferential direction, with a number of 3 or 2n (where n≥1 is a positive integer), forming a symmetrical spatial coordinate reference system. When X-rays are fluoroscopically viewed from different angles (such as anteroposterior, lateral, and oblique views), the relative positional relationship of the radiopaque markers 4 can clearly reflect the axial rotation angle, radial deployment state, and degree of adhesion to the vessel wall of the stent, avoiding positioning deviations caused by a single marker.

[0033] Specifically, the coating layer 2 and the support body 1 are fixedly connected, and the support body 1 and the coating layer 2 are fixedly connected by any one of the following processes: bonding, welding or sewing.

[0034] Specifically, the length of the stent body 1 is in the range of 10~70mm, and the outer diameter is in the range of 1.5~10mm; the outer diameter of the stent body 1 is less than or equal to the inner diameter of the stent cover layer 2. This ensures that the cover layer 2 fits tightly against the blood vessel wall after the stent body 1 expands, reducing the gap between the stent body 1 and the cover layer 2, effectively preventing postoperative endoleak (blood seeping into the tumor), and improving the sealing effect.

[0035] In other preferred embodiments, such as Figure 1 and Figure 4 As shown, when the covering layer 2 covers the entire area of ​​the stent body 1, it is used for aneurysms with narrow necks or aneurysms with many branches of the parent artery.

[0036] Specifically, for aneurysms with large and wide necks, local cladding may not be able to cover the entire neck, resulting in poor aneurysm healing. Therefore, when the aneurysm neck is wide, the cladding layer 2 covers the entire area of ​​the stent body 1.

[0037] In other preferred embodiments, such as Figure 3 and Figure 6 As shown, when the covering layer 2 covers a portion of the stent body 1, it is used for aneurysms with narrow necks or aneurysms with many branches of the parent artery.

[0038] Specifically, for some aneurysms with narrow necks, using full cladding may block blood flow to the perforating vessels above the parent artery, leading to cerebral infarction. Therefore, when the aneurysm neck is narrow, the cladding layer 2 covers a portion of the stent body 1.

[0039] In other preferred embodiments, the support body 1 has a rolled structure, and the coating layer 2 has a rolled structure or a continuous structure.

[0040] Specifically, such as Figure 3 and Figure 6 As shown, when the stent body 1 is a coiled structure and the covering layer 2 is a continuous structure, since the covering layer 2 is tightly attached to the blood vessel wall in the circumferential direction, the stent does not need to be deliberately adjusted after implantation, so that the neck of the aneurysm can be covered by the covering layer 2, effectively blocking the aneurysm without worrying about endoleak.

[0041] Specifically, such as Figure 7 and Figure 8 As shown, when the stent body 1 is a coiled structure and the covering layer 2 is also a coiled structure, the stent body 1 and the covering layer 2 can be coiled simultaneously during delivery in the catheter, which facilitates compression into the thin delivery catheter, reduces frictional damage to blood vessels during implantation, and is especially suitable for passing through tortuous or narrow blood vessel paths. It can have higher flexibility during delivery, and the overall stiffness of the stent is reduced, so the stent has lower delivery resistance.

[0042] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0043] In the description of this utility model, it should be understood that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0044] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0045] Those skilled in the art to which this invention pertains may make various modifications or additions to the specific embodiments described, or adopt similar methods to replace them, without departing from the spirit of this invention or exceeding the scope defined by the appended claims.

Claims

1. A covered stent, characterized in that, include: The stent body (1) has a self-expanding structure, and the proximal end of the stent body (1) is connected to a mechanically or electrically detachable delivery guide wire (3) for release after adjustment; A film layer (2) covers all or part of the area of ​​the support body (1); The coating layer and the support body (1) are fixedly connected.

2. The covered stent according to claim 1, characterized in that, When the covering layer (2) covers the entire area of ​​the stent body (1), it is used for aneurysms with a wide neck.

3. The covered stent according to claim 1, characterized in that, When the covering layer (2) covers a portion of the stent body (1), it is used for aneurysms with narrow necks or aneurysms with many branches of the parent artery.

4. A covered stent according to claim 1, characterized in that, The support body (1) is made of nickel-titanium alloy. The length of the support body (1) is in the range of 10~70mm and the outer diameter is in the range of 1.5~10mm. The outer diameter of the support body (1) is less than or equal to the inner diameter of the support coating layer (2).

5. A covered stent according to claim 1, characterized in that, The main body (1) of the support and the coating layer (2) are fixedly connected by any one of the following processes: bonding, welding or sewing.

6. A covered stent according to claim 1, characterized in that, The support body (1) has X-ray-proof imaging markers (4) at its ends; the coating layer (2) has X-ray-proof imaging markers (4) at both ends.

7. A covered stent according to claim 1, characterized in that, The main body of the support (1) is a rolled structure, and the coating layer (2) is a rolled structure or a continuous structure.

8. A covered stent according to claim 1, characterized in that, The coating layer (2) is made of at least one polymer material selected from expanded polytetrafluoroethylene, PU or PET.

9. A covered stent according to claim 8, characterized in that, The thickness of the polymer film of the coating layer (2) is 5 micrometers to 100 micrometers.

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