Filter screen and filter screen processing method

Abstract

The invention provides a filter screen and a filter screen processing method, and relates to the technical field of medical instruments.The filter screen comprises a plurality of wire materials, each wire material is wound to form a bent part used for being connected with an intravascular stent, and a first end and a second end which extend in the direction away from the intravascular stent are formed; the first end of any wire is at least crossed with the second end of another wire, and the second end of any wire is at least crossed with the first end of another wire. Moreover, a special processing mold is provided for the processing method of the filter screen, so that the filter screen can be stably formed, wires are prevented from being excessively bent, the processing mold is particularly suitable for processing and forming a degradable filter screen, the technical problem that the filter screen is firstly broken due to the existence of an excessively bent part in the biodegradation process can be avoided, and the medical safety is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a filter screen and a filter screen processing method. Background Art

[0002] There is a significant risk during the implantation of vascular stents, which may cause blood clots on the vessel wall to fall off, causing unexpected embolism in downstream vessels. Such embolism may lead to serious complications such as stroke or pulmonary embolism. Currently, there are protective devices on the market that can be deployed before stent implantation to prevent this complication. However, such stents are not biodegradable, and long-term implantation may cause blood vessel blockage and need to be removed after surgery.

[0003] The filter is woven from degradable materials and placed at the downstream end of the vascular stent to intercept the detached thrombus and prevent it from moving to the downstream blood vessels. It will degrade itself after the peak of thrombus detachment. However, the filter may break first at the large-angle bend of the wire, and then the filter fragments will fall off and migrate to the downstream blood vessels, which may cause serious complications. Summary of the invention

[0004] The object of the present invention is to provide a filter screen and a filter screen processing method to alleviate the technical problems of excessive bending parts and easy breakage of the filter screen.

[0005] In a first aspect, the filter screen provided by the present invention comprises a plurality of wires, each of which is wound to form a curved portion for connecting to a blood vessel stent, and forms a first end and a second end extending in a direction away from the blood vessel stent;

[0006] The first end of any of the wires at least crosses with the second end of another of the wires, and the second end of any of the wires at least crosses with the first end of another of the wires.

[0007] In combination with the first aspect, the present invention provides a first possible implementation manner of the first aspect, wherein the filter is in a conical structure, and its diameter gradually decreases from one end connected to the vascular stent to an end away from the vascular stent.

[0008] In combination with the first possible implementation manner of the first aspect, the present invention provides a second possible implementation manner of the first aspect, wherein the first ends and the second ends of the plurality of wires intersect at the tip of the tapered structure and are melt-welded.

[0009] In combination with the first aspect, the present invention provides a third possible implementation manner of the first aspect, wherein the intersecting first end head and the second end head are jointly arranged to form a strip-shaped filter hole area;

[0010] The first end and the second end located on both sides of the strip-shaped filter hole area are nearly parallel.

[0011] In combination with the first aspect, the present invention provides a fourth possible implementation of the first aspect, wherein the material of the wire is at least one of polybutylene carbonate, polylactic acid, polylactic acid-glycolic acid copolymer, polycaprolactone, magnesium alloy and zinc alloy.

[0012] In a second aspect, the filter screen processing method provided by the present invention adopts a processing mold for forming and preparing, and the processing mold includes: a cone portion, a plurality of cylindrical portions, a plurality of first limiting columns and a plurality of second limiting columns;

[0013] The plurality of cylindrical portions are arranged at intervals around the conical surface of the cone portion, and the plurality of cylindrical portions are respectively connected to the bottom of the conical surface of the cone portion;

[0014] The cylindrical portion, the first limiting pillar and the second limiting pillar are spaced from bottom to top along the conical surface of the cone portion, and a plurality of the first limiting pillars and a plurality of the second limiting pillars are spaced around the cone portion respectively;

[0015] On a projection plane perpendicular to the axis of the cone portion, between any two adjacent cylindrical portions there are flush first limiting columns and second limiting columns;

[0016] The filter screen processing method comprises the following steps:

[0017] Winding wires around the plurality of cylindrical portions one by one along the circumference of the cone portion, and folding each of the wires in half through the cylindrical portion to form a curved portion having a first end and a second end extending toward the tip of the cone portion;

[0018] The first end of any of the wires is crossed with at least the second end of another of the wires, the second end of any of the wires is crossed with at least the first end of another of the wires, and the first limiting column and the second limiting column are supported between the adjacent first end and the second end;

[0019] The first ends and the second ends of the plurality of wires are intersected at the tip of the cone portion and connected.

[0020] In combination with the second aspect, the present invention provides a first possible implementation manner of the second aspect, wherein the filter screen processing method further includes:

[0021] The wire material is heat treated so as to be shaped along the processing die.

[0022] In combination with the second aspect, the present invention provides a second possible implementation manner of the second aspect, wherein the step of intersecting and connecting the first ends and the second ends of the plurality of wires at the tip of the cone portion comprises:

[0023] A developing device is sleeved on the first end and the second end of the plurality of wires;

[0024] The first end head and the second end head are cut, and a plurality of the first end heads and a plurality of the second end heads are connected by hot-melt.

[0025] In combination with the second possible implementation of the second aspect, the present invention provides a third possible implementation of the second aspect, wherein, when cutting the first end head and the second end head, a length of the first end head and the second end head extending outside the developing device is reserved by 1 mm to 2 mm.

[0026] In combination with the second aspect, the present invention provides a fourth possible implementation manner of the second aspect, wherein the processing mold further includes a support column connected to the bottom of the cone portion;

[0027] The filter screen processing method also includes:

[0028] The plurality of curved portions are sutured and connected to the vascular stent respectively.

[0029] The embodiments of the present invention bring the following beneficial effects: each wire is wound to form a curved portion for connecting to a vascular stent, and to form a first end and a second end extending away from the vascular stent; the first end of any wire at least crosses with the second end of another wire, and the second end of any wire at least crosses with the first end of another wire; the wire is less bent during filter forming, and there are no excessive bending parts, which is particularly suitable for processing to form a degradable filter, and can avoid the technical problem of premature breakage due to the presence of excessive bending parts.

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related technologies, the drawings required for use in the specific embodiments or the related technical descriptions will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1A schematic diagram of a filter screen provided in an embodiment of the present invention;

[0033] Figure 2 A top view of a filter screen provided by an embodiment of the present invention;

[0034] Figure 3 A schematic diagram of a filter screen and a processing mold provided by an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of a filter and a vascular stent provided in an embodiment of the present invention.

[0036] Icons: 100 - wire; 101 - bending part; 102 - strip filter area; 110 - first end; 120 - second end; 200 - vascular stent; 300 - processing mold; 310 - cone part; 320 - cylindrical part; 330 - first limiting column; 340 - second limiting column; 350 - support column; 400 - developing device. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Physical quantities in formulas, if not separately marked, should be understood as basic quantities of the base units of the International System of Units, or derived quantities derived from the basic quantities through mathematical operations such as multiplication, division, differentiation or integration.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] like Figure 1 and Figure 2 As shown, the filter provided by the embodiment of the present invention includes a plurality of wires 100, each of which is wound to form a curved portion 101 for connecting to the vascular stent 200, and forms a first end 110 and a second end 120 extending away from the vascular stent 200; the first end 110 of any wire 100 at least crosses with the second end 120 of another wire 100, and the second end 120 of any wire 100 at least crosses with the first end 110 of another wire 100.

[0041] The filter screen described in this embodiment has fewer bends in the wire 100 and no excessive large-angle bends, which is suitable for processing with degradable materials and can avoid premature breakage due to excessive bends during the biodegradation process. In addition, the multiple wires 100 in the filter screen are clearly arranged and easy to process and shape.

[0042] In the embodiment of the present invention, the filter screen has a conical structure, and its diameter gradually decreases from one end connected to the vascular stent 200 to the other end away from the vascular stent 200 .

[0043] When the filter is used to capture thrombus, the detached thrombus will be captured in the conical tip area of ​​the filter, where the blood flow is fastest, which is conducive to the rapid dissolution of the thrombus and can prevent the thrombus from adhering to the blood vessel wall and causing organization, thereby reducing the risk of vascular stenosis and blockage.

[0044] In this embodiment, the first end 110 and the second end 120 of the plurality of wires 100 intersect at the tip of the conical structure and are melt-welded. The melt-welding can form a smooth connection between the ends of the first end 110 and the second end 120 to avoid scratches on the blood vessel wall caused by sharp parts.

[0045] Furthermore, the intersecting first end 110 and the second end 120 are jointly arranged to form a strip filter hole area 102; the first end 110 and the second end 120 located on both sides of the strip filter hole area 102 are close to parallel, which on the one hand ensures smooth blood flow, and on the other hand can reduce the curvature of the first end 110 and the second end 120 to avoid breakage due to excessive bending.

[0046] The filter screen described in this embodiment is particularly suitable for manufacturing from degradable materials, wherein the material of the wire 100 is at least one of polybutylene carbonate, polylactic acid, polylactic acid-glycolic acid copolymer, polycaprolactone, magnesium alloy and zinc alloy, and the diameter of the wire 100 is configured to be 0.2mm to 0.4mm. After being implanted in a blood vessel, it can be completely degraded in about six months, eliminating the need for surgical removal, thereby greatly reducing the risk of secondary surgery and related medical costs for patients.

[0047] like Figure 1 , Figure 2 and Figure 3 As shown, the filter processing method provided by the embodiment of the present invention adopts a processing mold 300 for molding preparation, and the processing mold 300 includes: a cone portion 310, a plurality of cylindrical portions 320, a plurality of first limiting columns 330 and a plurality of second limiting columns 340; the plurality of cylindrical portions 320 are arranged at intervals around the conical surface of the cone portion 310, and the plurality of cylindrical portions 320 are respectively connected to the bottom of the conical surface of the cone portion 310; the cylindrical portion 320, the first limiting column 330 and the second limiting column 340 are distributed at intervals from bottom to top along the conical surface of the cone portion 310, and the plurality of first limiting columns 330 and the plurality of second limiting columns 340 are respectively arranged at intervals around the cone portion 310; on the projection plane perpendicular to the axis of the cone portion 310, any two adjacent cylindrical portions 320 have flush first limiting columns 330 and second limiting columns 340.

[0048] The filter screen processing method comprises the following steps:

[0049] The wires 100 are wound around the plurality of cylindrical portions 320 one by one along the circumference of the cone portion 310, and each wire 100 is folded in half through the cylindrical portion 320 to form a curved portion 101 having a first end 110 and a second end 120 extending toward the tip of the cone portion 310;

[0050] The first end 110 of any wire 100 at least crosses with the second end 120 of another wire 100, the second end 120 of any wire 100 at least crosses with the first end 110 of another wire 100, and the first limiting column 330 and the second limiting column 340 are supported between the adjacent first end 110 and the second end 120;

[0051] The first ends 110 and the second ends 120 of the plurality of wires 100 intersect at the tip of the cone portion 310 and are connected.

[0052] Among them, the height of the cone part 310 is about 20mm, the bottom diameter is about 30mm, the diameter of the cylindrical part 320 is 7mm, the diameters of the first limiting column 330 and the second limiting column 340 are both 1mm, and any wire 100 along the processing mold 300 has a smooth transition at all places to avoid excessive bending of the wire 100.

[0053] In the embodiment of the present invention, the filter screen processing method further includes: heat treating the wire 100 , heating and then cooling the wire 100 so that the wire 100 is shaped along the processing mold 300 .

[0054] Furthermore, the step of intersecting and connecting the first end 110 and the second end 120 of the plurality of wires 100 at the tip of the cone portion 310 includes:

[0055] A developing device 400 is sleeved on the first end 110 and the second end 120 of the plurality of wires 100;

[0056] The first end pieces 110 and the second end pieces 120 are cut, and a plurality of the first end pieces 110 and a plurality of the second end pieces 120 are connected by heat-melting.

[0057] When cutting the first terminal 110 and the second terminal 120 , a length of the first terminal 110 and the second terminal 120 extending outside the developing device 400 is reserved by 1 mm to 2 mm, so as to reserve sufficient process space for the hot melt connection operation.

[0058] See also Figure 3 and Figure 4 The processing mold 300 also includes a support column 350 connected to the bottom of the cone portion 310; the filter screen processing method also includes: suturing and connecting the multiple curved portions 101 to the vascular stent 200. During processing, after the filter screen is heat-treated and shaped, the first end 110 and the second end 120 of the multiple wires 100 are intersected and hot-melted, and then the filter screen is removed from the cone portion 310, and then the multiple curved portions 101 of the filter screen are sutured and connected to the vascular stent 200, so that the filter screen and the vascular stent 200 are connected in the circumferential direction.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A filter screen, characterized in that: It comprises a plurality of wires (100), each of the wires (100) being wound to form a curved portion (101) for connecting to a blood vessel stent (200), and forming a first end (110) and a second end (120) extending in a direction away from the blood vessel stent (200); The first end (110) of any of the wires (100) crosses with the second end (120) of at least another of the wires (100), and the second end (120) of any of the wires (100) crosses with the first end (110) of at least another of the wires (100).

2. The filter screen according to claim 1, characterized in that: The filter screen has a conical structure, and its diameter gradually decreases from one end connected to the vascular stent (200) to one end away from the vascular stent (200).

3. The filter screen according to claim 2, characterized in that: The first ends (110) and the second ends (120) of the plurality of wires (100) intersect at the tip of the conical structure and are melt-welded.

4. The filter screen according to claim 1, characterized in that: The first end (110) and the second end (120) intersecting each other are jointly arranged to form a strip-shaped filter hole area (102); The first end (110) and the second end (120) located on both sides of the strip-shaped filter hole area (102) are approximately parallel.

5. The filter screen according to claim 1, characterized in that: The material of the wire material (100) is at least one of polybutylene carbonate, polylactic acid, polylactic acid-glycolic acid copolymer, polycaprolactone, magnesium alloy and zinc alloy.

6. A filter screen processing method, characterized in that: The filter screen processing method adopts a processing mold (300) for molding and preparation, wherein the processing mold (300) comprises: a cone portion (310), a plurality of cylindrical portions (320), a plurality of first limiting columns (330) and a plurality of second limiting columns (340); The plurality of cylindrical portions (320) are arranged at intervals around the conical surface of the cone portion (310), and the plurality of cylindrical portions (320) are respectively connected to the bottom of the conical surface of the cone portion (310); The cylindrical portion (320), the first limiting column (330) and the second limiting column (340) are spaced from bottom to top along the conical surface of the cone portion (310), and a plurality of the first limiting columns (330) and a plurality of the second limiting columns (340) are spaced around the cone portion (310). On a projection plane perpendicular to the axis of the cone portion (310), there are flush first limiting columns (330) and second limiting columns (340) between any two adjacent cylindrical portions (320); The filter screen processing method comprises the following steps: Wires (100) are wound around the plurality of cylindrical portions (320) one by one along the circumference of the cone portion (310), and each of the wires (100) is folded in half through the cylindrical portion (320) to form a curved portion (101) having a first end (110) and a second end (120) extending toward the tip of the cone portion (310); The first end (110) of any of the wires (100) is crossed with at least the second end (120) of another of the wires (100), the second end (120) of any of the wires (100) is crossed with at least the first end (110) of another of the wires (100), and the first limiting column (330) and the second limiting column (340) are supported between adjacent first end (110) and second end (120); The first ends (110) and the second ends (120) of the plurality of wires (100) are intersected at the tip of the cone portion (310) and connected.

7. The filter screen processing method according to claim 6, characterized in that: The filter screen processing method also includes: The wire material (100) is heat treated so that the wire material (100) is shaped along the processing mold (300).

8. The filter screen processing method according to claim 6, characterized in that: The step of intersecting and connecting the first end heads (110) and the second end heads (120) of the plurality of wires (100) at the tip of the cone portion (310) comprises: A developing device (400) is sleeved on the first end (110) and the second end (120) of the plurality of wires (100); The first end head (110) and the second end head (120) are cut, and a plurality of the first end heads (110) and a plurality of the second end heads (120) are connected by hot-melt connection.

9. The filter screen processing method according to claim 8, characterized in that: When cutting the first end head (110) and the second end head (120), a length of 1 mm to 2 mm of the first end head (110) and the second end head (120) extending outside the developing device (400) is reserved.

10. The filter screen processing method according to claim 6, characterized in that: The processing mold (300) further comprises a support column (350) connected to the bottom of the cone portion (310); The filter screen processing method also includes: The plurality of curved portions (101) are respectively sutured and connected to the blood vessel stent (200).

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