CN110772361A - Medical stent and method of forming same - Google Patents

Abstract

The invention relates to the field of medical instruments, and provides a medical stent which comprises a tubular grid structure formed by a plurality of interconnected wave bars, wherein at least one wave bar is provided with an enhanced developing area, and a developing wire winding is wound on the enhanced developing area, so that the developing performance of the medical stent is enhanced, and the conveying resistance of the medical stent is not increased. Furthermore, the wave rod is in the enhancement development district still is provided with and is located the limit structure at development silk winding both ends, limit structure can avoid the development silk winding to take place to shift or separate soon, thereby utilizes the development image's that medical support obtained accuracy is higher. The invention also provides a forming method of the medical stent, the cost is lower, and the formed medical stent has the same or similar advantages.

Description

Medical stent and method of forming same

Technical Field

The invention relates to the field of medical instruments, in particular to a medical stent and a forming method thereof.

Background

Cardiovascular and cerebrovascular diseases have gradually become one of the main diseases causing human disability and death, an intravascular stent interventional operation conveys a medical stent to a diseased position in a blood vessel through a catheter, and blood vessel recanalization is realized by expanding and opening a focus.

In order to facilitate a doctor to accurately position, release and adjust the medical stent in the operation process and judge whether the stent is displaced, thrombus is formed and the like in the postoperative follow-up, the image of the medical stent needs to be observed under the irradiation of an X-ray instrument or related medical imaging equipment, so that the medical stent is required to have better developing performance. Especially for intracranial vessels with skull interference, it is important to enhance the development performance of the stent. However, in consideration of mechanical properties, corrosion resistance, biocompatibility and the like of the medical stent, the main body of the stent is usually made of stainless steel, cobalt-chromium alloy, nickel-titanium alloy, magnesium alloy, polymer or the like, and the stent has relatively poor visibility under the irradiation of an X-ray apparatus and related medical imaging equipment, and has an undesirable developing effect.

In order to enhance the visualization performance of the medical stent, the currently common method is to widen and/or thicken the wave rod of the medical stent as a whole, however, this method increases the amount of metal required for manufacturing the medical stent, which increases the risk of biocompatibility and increases the probability of thrombosis clinically, and on the other hand, the increase of the amount of metal causes the stent to become hard, resulting in an increase of the resistance when the medical stent is pushed into the blood vessel.

At present, another method for enhancing the development performance of the medical stent is to integrally wind a development wire on the stent from the proximal end to the distal end of the stent, but the manufacturing cost of integrally winding the development wire on the stent is high, and the development wire is easy to loosen, so that the development wire can slide (shift) on a wave rod of the medical stent when the medical stent is conveyed, on one hand, the conveying resistance is increased, and on the other hand, the accuracy of a developed image can also be influenced.

Disclosure of Invention

In order to overcome the problems of the existing method for enhancing the development performance of the medical stent, the invention provides the medical stent and the forming method of the medical stent, which can enhance the development performance of the medical stent on one hand, cannot cause obvious resistance to the conveying of the medical stent in a blood vessel on the other hand, and have higher accuracy of developed images.

According to one aspect of the present invention, there is provided a medical stent comprising a tubular lattice structure of a plurality of interconnected wave bars, at least one of the wave bars having an enhanced development zone, the wave bar being wound with a development wire winding in the enhanced development zone, the development wire winding comprising at least one layer of development wire coils wound with development wire.

Optionally, the wave rod is in the enhanced developing area is further provided with a limiting structure, and the limiting structure is located at two ends of the developing wire winding and used for limiting the developing wire winding to move or unscrew on the wave rod.

Optionally, a difference between the width of the limiting structure and the width of the wave rod at the position where the developing wire winding is wound is greater than or equal to a difference between the thickness of the developing wire winding and the radius of the developing wire, and is less than or equal to the thickness of the developing wire winding.

Optionally, the medical stent comprises a plurality of the enhanced development zones, and the plurality of enhanced development zones are distributed along the axial direction of the tubular lattice structure in a staggered manner.

Optionally, the plurality of developer wire windings are helically distributed along the axial direction of the tubular mesh structure.

Optionally, the width of the wave bar in the enhanced development area is greater than or equal to the width of the wave bar except for the enhanced development area, and the width of the wave bar at the position where the developing wire winding is wound is in a range of 0.2mm to 0.4 mm.

Optionally, each layer of the developing wire coil comprises 8-10 periods.

Optionally, the diameter of the developing wire ranges from 0.001 inch to 0.003 inch.

Optionally, the developing wire is made of one or a combination of more of gold, silver, platinum, rhodium, iridium, palladium, rhenium, tungsten, and tantalum.

Optionally, one or more of the enhanced developing regions are disposed on the same wave bar.

Optionally, in a plane extending perpendicular to the wave rod, the cross section of the limiting structure is a combination of one or more of an arc shape, a triangle shape, a square shape, a trapezoid shape and other polygons.

Optionally, in the plane where the tubular mesh structure is unfolded, the cross section of the limiting structure is a combination of one or more of circular arc, triangle, square, trapezoid and other polygons.

According to another aspect of the present invention, there is also provided a method of forming a medical stent, the method comprising: a stent forming a tubular lattice structure, the tubular lattice structure further comprising a plurality of interconnected wave bars; and arranging an enhanced developing area on at least one wave rod, and winding at least one layer of developing wire coil with a spiral structure at the enhanced developing area by using a developing wire to form a developing wire winding.

According to the medical support provided by the invention, the enhanced developing area is arranged on at least one wave rod, and the developing wire winding is wound in the enhanced developing area, so that the developing performance of the medical support is enhanced, and the conveying resistance of the medical support is not increased. Furthermore, the wave rod is in the enhancement development district still is provided with and is located the limit structure at development silk winding both ends, limit structure can avoid the development silk winding to take place to shift or separate soon, thereby utilizes the development image's that medical support obtained accuracy is higher.

The method for forming the medical stent comprises the steps of firstly forming the stent with a tubular network structure, arranging a plurality of wave bars which are connected with each other on at least one of the wave bars, then arranging an enhanced developing area on at least one of the wave bars, and winding at least one layer of developing wire coil with a spiral structure at the enhanced developing area to form a developing wire winding. The medical stent has the same or similar advantages as the medical stent of the invention, and the forming method of the medical stent has lower cost.

Drawings

Fig. 1 is a schematic view of a medical stent according to an embodiment of the present invention.

Fig. 2 is a schematic deployment plan view of a medical stent according to an embodiment of the present invention.

FIG. 3 is a schematic view of an enhanced development zone in accordance with one embodiment of the present invention.

FIG. 4 is a schematic view of a wave bar and developer wire winding in another embodiment of the invention.

Fig. 5 is a schematic diagram of an enhanced development area and a position-limiting structure according to an embodiment of the invention.

Fig. 6(a) to 6(f) are schematic diagrams of an enhanced developing area and a position-limiting structure according to another embodiment of the present invention.

Fig. 7 is a flow chart of a method of forming a medical stent in accordance with an embodiment of the present invention.

Description of reference numerals:

10-medical stent; 100-wave rod; 100 a-an enhanced development zone; 110-a developing wire winding; 120-limit structure.

Detailed Description

The medical stent and the forming method of the present invention will be described in further detail with reference to the accompanying drawings and specific examples. The advantages and features of the present invention will become more apparent from the following description. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely intended to facilitate the clear description of the embodiments of the invention.

As described in the background art, the conventional method for enhancing the development performance of the medical stent is to widen and/or thicken the wave rod of the medical stent integrally or to wind the development wire on the stent integrally, but widening and/or thickening the wave rod integrally increases the amount of metal of the medical stent, which is not beneficial to the treatment effect and increases the difficulty of conveying the medical stent in the catheter, and the development wire is wound on the stent integrally at a high cost, and is easy to loosen and cause displacement in the conveying process, which affects the accuracy of the developed image.

Fig. 1 is a schematic view of a medical stent according to an embodiment of the present invention. Fig. 2 is a schematic deployment plan view of a medical stent according to an embodiment of the present invention. It will be appreciated by those skilled in the art that the medical stent of the present invention is in a tubular configuration as shown in fig. 1 in actual use, but may be depicted in the expanded plan view of fig. 2 for clarity of illustration. Hereinafter, a medical stent according to an embodiment of the present invention will be described with reference to fig. 2. FIG. 3 is a schematic view of an enhanced development zone in accordance with one embodiment of the present invention. A medical stent according to an embodiment of the present invention will be described with reference to fig. 1 to 3.

Referring to fig. 1 to 3, in an embodiment of the present invention, the medical stent 10 includes a tubular mesh structure, the tubular mesh structure further includes a plurality of wave bars 100 connected to each other, at least one wave bar 100 is provided with an enhanced development area 100a, the wave bar 100 is wound with a developing wire winding 110 in the enhanced development area 100a, and the developing wire winding 110 includes at least one layer of developing wire coil formed by winding developing wire.

Specifically, the medical stent 10 may be a metal stent or a non-metal stent. The medical stent 10 comprises a tubular lattice structure as shown in fig. 1, wherein each lattice may be composed of a plurality of struts as a wave ring. The tubular lattice structure for example comprises a plurality of nodes connecting a plurality of wave bars 100, which plurality of wave bars 100 may also be considered as edges of said wave ring. In the embodiment shown in fig. 1 and 2, each of the wave rings is composed of four wave rods 100, but the present invention is not limited thereto, and a plurality of wave rods 100 connected to each other may also be composed of wave rings of other shapes, which serve as meshes of the tubular mesh structure.

In order to enhance the developing performance, the medical stent of the present embodiment is provided with an enhanced developing area 100a on at least one wave bar 100, and a developing wire winding 110 is wound around the enhanced developing area 100 a. Further, the medical stent 10 of the present embodiment is provided with a plurality of enhanced developing areas 100a and corresponding developing wire windings 110.

Specifically, the plurality of enhanced development zones 100a may be uniformly distributed along the surface of the medical stent 10 (tubular lattice structure), for example, may be uniformly distributed along the axial and/or circumferential direction of the medical stent 10. Further, the plurality of enhanced development zones 100a may be distributed along the axial direction of the tubular lattice structure (i.e., not on one axis, but on a plurality of axial lines of the outer circumferential surface of the tubular lattice structure) in a staggered manner so that the displayed image in the developed condition reflects the morphology of the medical stent 10 in the axial and circumferential directions. Preferably, the plurality of enhanced developing areas 100a are spirally distributed along the axial direction of the medical stent 10, which has the technical effects that on one hand, images displayed by the medical stent 10 under a developing condition can uniformly reflect the overall contour of the medical stent 10, and on the other hand, the number of the developing wire windings 110 can be reduced, the conveying resistance of the medical stent 10 is reduced, and the manufacturing cost is saved.

The position of the enhanced developing area 100a on the wave bar 100 can be set as required, and for the convenience of winding, the enhanced developing area 100a can be disposed in the middle area of the wave bar 100, that is, the enhanced developing area 100a is located in the middle area of the wave bar 100, but is not limited thereto, and the enhanced developing area 100a and the developing wire winding 110 can also be located in the end area of the wave bar 100. In addition, for the same wave bar 100, one enhanced developing area 100a may be provided and the developing wire winding 110 may be provided in the enhanced developing area 100a, but the invention is not limited thereto, and a plurality of enhanced developing areas 100a may also be provided on the same wave bar 100. FIG. 4 is a schematic view of a wave bar and developer wire winding in another embodiment of the invention. Referring to fig. 4, in another embodiment, three enhanced developing regions 100a are provided on the same wave bar 100.

The developing wire winding 110 is formed by winding a developing wire in the enhanced developing area 100a wound on the wave bar 100, and the material of the developing wire can enhance the definition of a developed image under the irradiation of an X-ray apparatus or related medical imaging equipment, and is used for enhancing the developing performance of the medical stent 10 in this embodiment. The term "developability" as used herein refers to the visibility of the developed image of the medical stent under the irradiation of an X-ray apparatus or related medical imaging equipment, and the clearer the developed image, the better the developability. The developing wire may be made of metal material, and may include one or more of gold, silver, platinum, rhodium, iridium, palladium, rhenium, tungsten and tantalum. The diameter (or wire diameter) of the developing wire is in the range of 0.001 inch to 0.008 inch, and in consideration of the developing effect and the conveyance resistance, it is preferable that the developing wire winding 110 is formed by selecting a developing wire having a diameter in the range of 0.001 inch to 0.003 inch.

The cross section of the developing wire can be one or a combination of a plurality of shapes of circles, ellipses, triangles, squares, trapezoids and other polygons, and the developing wire with the circular cross section can be selected from the view point of simple and convenient manufacture. For the same developing wire winding 110, one or more layers of developing wire coils may be included, which refer to coils that are formed in the same plane after the developing wire is wound around the enhanced developing region 100a of the wave bar 100. Each developing wire coil is formed by tightly winding the developing wires in the same direction and at the same angle, and adjacent windings are tightly attached or have no gap. The number of winding cycles of the same developing wire coil can be determined according to the length of the enhanced developing area 100a on the wave rod 100 and the developing effect to be achieved, in the embodiment, each layer of the developing wire coil can comprise 5-15 winding cycles, preferably, each layer of the developing wire coil comprises 8-10 winding cycles, so that the developing effect and the conveying resistance are balanced.

In order to limit the position of the developing wire winding 110 and the winding density of the developing wire, and avoid that the developing wire winding 110 is displaced or unscrewed during the transportation process or after being placed into a blood vessel to affect the developing performance and the accuracy of an image, referring to fig. 3, in this embodiment, for the wave rod 100 provided with the enhanced developing area 100a, the wave rod 100 is further provided with a limiting structure 120 in the enhanced developing area 100 a. In addition, in order to enhance the developing effect of the medical stent 10 in the enhanced developing area 100a, in some embodiments, the developing performance of the medical stent 10 is further enhanced by increasing the width of the wave bar at the enhanced developing area 100a, thereby simultaneously increasing the width of the developing wire winding 110 at the enhanced developing area and increasing the metal amount of the enhanced developing area 100a, without widening or thickening the wave bar 100 of the medical stent 10 as a whole, so that the conveying resistance of the medical stent 10 is hardly affected. FIG. 5 is a schematic diagram of an enhanced development area and a limiting structure according to one embodiment of the invention. Fig. 6(a) to 6(f) are schematic diagrams of the enhanced developing area and the position limiting structure in other embodiments of the present invention. The enhanced development area and the position limiting structure according to the embodiment of the present invention will be described below with reference to fig. 5 and fig. 6(a) to 6 (f).

Referring to fig. 5, since the outer diameter of the developing wire winding 110 is related to the width of the wave bar 100 in the enhanced developing area 100a and the thickness of the developing wire winding 110, in addition to increasing the outer diameter of the developing wire winding 110 by the diameter of the developing wire and the number of layers of the developing wire coil, in order to enhance the developing performance of the medical stent 10, in some embodiments, the width of the wave bar 100 in the enhanced developing area 100a may be set to be greater than or equal to the width of the same wave bar 100 in other areas except the enhanced developing area 100 a. The "width" herein refers to the distance between the two side edges of the wave bar extending along the surface of the medical stent 10 (i.e., the plane in which the medical stent 10 is deployed) and perpendicular to the direction of extension of the wave bar. Specifically, in the present embodiment, the range of the wave bar width D of the enhanced developing area 100a where the developing wire winding 110 is wound may be set to 0.08mm to 0.5mm, and more preferably, the range of the wave bar width D of the enhanced developing area 100a where the developing wire winding 110 is wound may be set to 0.2mm to 0.4 mm.

The limiting structures 120 are located at two ends of the developing wire winding 110, and are used for limiting the developing wire winding 110 to move or unscrew on the wave rod 100. Specifically, the position limiting structure 120 may include a set of stoppers located at two ends of the developing wire winding 110, and the stoppers are shaped like ears and are disposed at two ends of the developing wire winding 110. When the developing wire is wound in the enhanced developing area 100a of the wave bar 100 to form a developing wire coil with a spiral structure, the limiting structure 120 may also be used to fix two ends of the developing wire coil, so that the limiting structure 120 has an anti-unwinding effect (e.g., the spiral structure of the developing wire coil may be maintained, and the developing wire coil is prevented from being loosened). Referring to fig. 5 and fig. 6(a) to 6(f), the cross-section of the limiting structure 120 in the plane of the medical stent 10 may be one or a combination of circular arc, triangle, square, trapezoid and other polygons. Furthermore, the cross section of the limiting structure 120 in a plane perpendicular to the extending direction of the wave bar 100 may be one or a combination of more than one of circular arc, triangle, square, trapezoid and other polygons. In addition, the set of position-limiting structures 120 at the two ends of the developing wire winding 110 may be disposed on the same side (see fig. 6(b)) or opposite side (see fig. 6(a)) of the corresponding wave bar 100, or a pair of the two sides (see fig. 6(d) to 6(f)), or a pair of the two sides and one of the two sides (see fig. 6(c)), and the like, and may be determined comprehensively according to the position of the wave bar 100 on the bracket 10, the position and the number of the enhanced developing regions 100a on the wave bar 100, and the like.

Referring to fig. 5, in order to limit the displacement or unwinding of the developing wire winding 110, the width D' of the limiting structure 120 is greater than the width D of the wave bar where the developing wire winding 110 is wound. The width D' of the position-limiting structure 120 refers to the distance between the vertex of the position-limiting structure 120 and the opposite side edge of the wave bar 100 where the developing wire winding 110 is wound adjacently, in the extending direction along the surface (the unfolded plane) of the medical stent 10 and perpendicular to the wave bar 100. In order to prevent the developing wire winding 110 from slipping past the position limiting structure 110, in the present embodiment, the difference between the width D 'of the position limiting structure 120 and the corresponding width D of the wave bar where the developing wire winding 110 is wound (i.e., D' -D) is preferably greater than or equal to the difference obtained by subtracting the radius of the developing wire from the thickness of the developing wire winding 110 (which refers to the distance from the inner diameter of the developing wire coil at the innermost turn to the outer diameter of the developing wire coil at the outermost turn, i.e., the product of the number of turns of the developing wire coil multiplied by the diameter of the developing wire). Further, in order to avoid the increase of the conveying resistance of the medical stent 10 caused by the excessively large width D ' of the position-limiting structure 120, it is preferable that the difference between the width D ' of the position-limiting structure 120 and the corresponding width D of the wave bar where the developing wire winding 110 is wound (i.e., D ' -D) is smaller than or equal to the thickness of the corresponding developing wire winding 110. For example, when the developing wire winding 110 includes n layers of developing wire coils (n is an integer greater than or equal to 1), wherein the diameter of the developing wire is set to D, the difference between the width D 'of the position limiting structure 120 and the corresponding width D of the wave bar where the developing wire winding 110 is wound (i.e., D' -D) may be set to range from (n-0.5) D to nd.

As can be seen from the above description, the medical stent 10 of the present embodiment is advantageous to enhance the developing performance of the medical stent 10 by providing the development-enhancing area 100a on the wave bar 100 and winding the developing wire winding 110 on the development-enhancing area 100a, and does not increase the conveying resistance of the medical stent 10. Further, the wave bar 100 is further provided with a limiting structure 120 at two ends of the developing wire winding 110 in the enhanced developing area 100a, and the limiting structure 120 can prevent the developing wire winding 110 from shifting or untwisting, so that the accuracy of the developed image obtained by using the medical stent 10 is high.

The embodiment of the invention also comprises a forming method of the medical stent. Fig. 7 is a flow chart of a method of forming a medical stent in accordance with an embodiment of the present invention. Referring to fig. 7, a method for forming a medical stent according to an embodiment of the present invention includes the steps of:

s1: a stent forming a tubular lattice structure, the tubular lattice structure further comprising a plurality of interconnected wave bars;

s2: and arranging an enhanced developing area on at least one wave rod, and winding at least one layer of developing wire coil with a spiral structure at the enhanced developing area to form a developing wire winding.

In step S1, the method for forming the tubular mesh structure may use a laser cutting or weaving method, preferably a laser cutting method. The process for forming a medical stent using laser cutting can be performed by those skilled in the art with reference to the prior art.

In step S2, it is preferable that the developing device further includes a limiting structure at two ends of the developing wire winding to limit the developing wire winding from moving or unwinding on the corresponding wave bar in the enhanced developing area.

The medical stent 10 according to the embodiment of the present invention can be formed by the above-described method of forming a medical stent. The developing wire winding is arranged on at least one wave rod to form an enhanced developing area, so that the developing performance of the medical stent is enhanced, the conveying resistance of the medical stent is not increased, and the forming method of the medical stent is low in cost. The two ends of the developing wire winding are provided with the limiting structures, so that the developing wire winding can be prevented from shifting or unwinding, and the accuracy of the developed image obtained by the medical support is high.

It should be noted that, in the present specification, the embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other. For the method disclosed by the embodiment, the description is relatively simple because the method corresponds to the structure disclosed by the embodiment, and the relevant points can be referred to the structural part for description.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the claims of the present invention, and those skilled in the art can make possible variations and modifications of the technical solutions of the present invention using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. For example, the medical stent of the present invention includes, but is not limited to, a vascular stent, and may be any one of human body lumen stents such as a biliary stent, an esophageal stent, an intestinal stent, a urethral stent, a prostate stent, and an orthopedic stent, and the vascular stent may be a coronary stent, a cerebral artery stent, an aortic stent, a renal artery stent, a peripheral artery stent, a venous stent, and the like. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention, unless the content of the technical solution of the present invention is departed from.

Claims (13)

1. The utility model provides a medical support, its characterized in that includes a tubulose grid structure of constituteing by a plurality of interconnect's ripples pole, at least one be provided with reinforcing development district on the ripples pole, the ripples pole is in reinforcing development district twines has the development silk winding, the development silk winding includes the development silk coil that at least one deck formed by the winding of development silk.

2. The medical stent of claim 1, wherein the wave bar is further provided with a limiting structure in the enhanced developing area, and the limiting structure is positioned at two ends of the developing wire winding and used for limiting the developing wire winding to move or unscrew on the wave bar.

3. The medical stent of claim 2, wherein the difference between the width of the limiting structure and the width of the wave bar where the developing wire winding is wound is greater than or equal to the difference between the thickness of the developing wire winding and the radius of the developing wire and less than or equal to the thickness of the developing wire winding.

4. The medical stent of claim 1, wherein said medical stent comprises a plurality of said enhanced development zones, and said plurality of enhanced development zones are distributed along an axial offset of said tubular lattice structure.

5. The medical stent of claim 4, wherein said plurality of windings of contrast wire are helically distributed along the axial direction of said tubular lattice structure.

6. The medical stent of claim 1, wherein the width of the wave bar in the enhanced development zone is greater than or equal to the width of the wave bar except for the enhanced development zone, and the width of the wave bar where the developing wire winding is wound ranges from 0.2mm to 0.4 mm.

7. The medical stent of claim 1, wherein each layer of said coil of developer wire comprises 8 to 10 cycles.

8. The medical stent of any one of claims 1 to 7, wherein the diameter of the visualization wire ranges from 0.001 inches to 0.003 inches.

9. The medical stent of any one of claims 1 to 7, wherein the developing wire is made of one or more of gold, silver, platinum, rhodium, iridium, palladium, rhenium, tungsten and tantalum.

10. The medical stent of any one of claims 1 to 7, wherein one or more of said enhanced development zones are provided on the same wave bar.

11. The medical stent of any one of claims 1 to 7, wherein the cross-section of the limiting structure in a plane extending perpendicular to the wave bar is a combination of one or more of a circular arc, a triangle, a square, a trapezoid and other polygons.

12. The medical stent as claimed in any one of claims 1 to 7, wherein the cross-section of the limiting structure in the plane of expansion of the tubular lattice structure is one or a combination of more of circular arc, triangle, square, trapezoid and other polygons.

13. A method of forming a medical stent, comprising:

a stent forming a tubular lattice structure, the tubular lattice structure further comprising a plurality of interconnected wave bars; and

and arranging an enhanced developing area on at least one wave rod, and winding at least one layer of developing wire coil with a spiral structure by using a developing wire in the enhanced developing area to form a developing wire winding.

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