An intracranial embolic protection device

Abstract

The utility model provides a kind of intracranial embolism protection device, it is related to medical instrument technical field, including guide wire and filter screen assembly connected with guide wire, filter screen assembly includes filter screen first section and filter screen second section, filter screen first section includes external connecting tendon and middle connecting tendon, middle connecting tendon includes several polygonal braiding frame, external connecting tendon includes several circular arc braiding frame, filter screen second section proximal end is connected with the distal end of filter screen first section, distal end circular arc is closed, and diameter gradually decreases from proximal end to distal end, the mesh diameter of filter screen second section is less than the mesh diameter of filter screen first section. By setting the filter screen first section and filter screen second section of different braiding density, make filter screen assembly have better compliance, cooperate and set developing ring, improve braiding material, so that the visibility of intracranial embolism protection device is better, convenient operation.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, and in particular to an intracranial embolism protection device. Background Technology

[0002] Stroke has become a focus of attention in recent years. As a relatively common cerebrovascular disease in clinical practice, mild cases have a good prognosis, while severe cases are life-threatening. Ischemic stroke has been confirmed as a high-risk factor for sudden death in the elderly. The brain damage caused by this disease is quite severe in a short period of time, and it is the most important factor in human disability.

[0003] Studies show that over 80% of strokes are ischemic strokes, while about 20% are hemorrhagic strokes. Ischemic strokes are mainly caused by insufficient blood supply to the brain due to carotid artery stenosis and intracranial vascular stenosis, or by cerebral embolism, while hemorrhagic strokes are mainly caused by subarachnoid hemorrhage resulting from ruptured cerebral aneurysms.

[0004] For ischemic stroke, common techniques include interventional balloon angioplasty and stent placement. However, balloon angioplasty may cause plaque or thrombus to detach and travel to distal sites with the blood flow, potentially causing cerebral infarction and resulting in poor prognosis. Therefore, embolization protection devices are selected to protect distal blood vessels, capture detached thrombi, and prevent intracranial embolism.

[0005] Currently available embolism protection devices typically use a sculpted support with a polyurethane coating for the filter, which lacks flexibility and presents significant resistance during insertion, making it difficult to reach narrowed areas of intracranial arteries, such as the C6 and C7 segments. Furthermore, these products offer poor visibility during operation, making it difficult to accurately determine the location in severe cases, potentially causing harm to the patient. This application addresses these shortcomings. Utility Model Content

[0006] The purpose of this invention is to provide an intracranial embolism protection device to solve the problems of insufficient flexibility and high insertion resistance of traditional embolism protection devices.

[0007] To address the aforementioned problems, this utility model provides an intracranial embolism protection device, comprising a guidewire and a filter assembly connected to the guidewire. The filter assembly includes a first filter section and a second filter section. The first filter section includes an outer connecting rib and a middle connecting rib. The middle connecting rib includes several polygonal braided frames, such as rhombuses or other quadrilaterals, preferably employing a rhombus-like structure with rounded corners. The outer connecting rib includes several arc-shaped braided frames, such as semi-circular braided frames. The arc-shaped braided frames and the polygonal braided frames... The filter screen is connected in the following way: the proximal end of the second segment is connected to the distal end of the first segment, and the distal end is closed in an arc shape with a gradually decreasing diameter from the proximal end to the distal end to reduce penetration resistance. The mesh diameter of the second segment is smaller than that of the first segment, and the length of adjacent nodes of the mesh in the second segment does not exceed 130 μm. During the operation, embolic fragments flow with the blood and are captured and intercepted by the second segment of the filter screen. When the embolism protection device is withdrawn, it will also carry the embolic fragments out of the blood vessel. The second segment of the filter screen can capture embolic fragments with a diameter greater than 130 μm.

[0008] Preferably, the arc portion of the arc-shaped woven frame is tangent to and connected to the arc of the polygonal woven frame.

[0009] According to one embodiment of the present invention, in order to solve the problem of poor visibility in traditional intracranial embolism protection devices, imaging rings are installed on both sides of the filter assembly, namely a first imaging ring and a second imaging ring, and the guide wire coincides with the axis of the imaging ring.

[0010] According to one embodiment of the present invention, the length ratio of the first segment to the second segment of the filter is 3:1, ensuring both flexibility and support performance.

[0011] According to one embodiment of the present invention, the length of adjacent nodes of the mesh in the second segment of the filter gradually decreases from the near end to the far end, thereby improving the capture effect of emboli and fragments.

[0012] According to one embodiment of the present invention, the first section and the second section of the filter screen may be made of the same material or different materials of metal braided wire.

[0013] Furthermore, the first and / or second sections of the filter screen are made of platinum-core nickel-titanium wire braided wire, characterized by a nickel-titanium alloy coating platinum, with platinum accounting for no more than 40% of the cross-sectional area of ​​the entire metal braided wire. This ensures a consistent developing effect throughout the entire device.

[0014] According to one embodiment of the present invention, the diameter of the braided filaments in the second section of the filter screen is ≤0.032mm.

[0015] According to one embodiment of the present invention, the guidewire is provided with a bending and shaping part. The hardness of the bending and shaping part is lower than that of other parts of the guidewire. The operator can perform plastic bending on this part. The softer part can be bent into various shapes, such as "J", "S" and other irregular shapes, which is conducive to passing through various irregular blood vessels.

[0016] According to one embodiment of the present invention, the guidewire surface is provided with a polytetrafluoroethylene coating to increase the lubricity of the guidewire and reduce the frictional resistance of the guidewire as it passes through the catheter and blood vessel.

[0017] According to one embodiment of the present invention, the distal end of the guidewire is configured with a bullet-shaped structure to reduce the resistance of the guidewire entering the catheter and blood vessel, while reducing damage to the patient's blood vessels.

[0018] The beneficial effects of this utility model are that by setting the first and second sections of the filter screen with different weaving densities, the filter screen assembly has better flexibility and reduces insertion resistance. The structure of the first section of the filter screen and the length ratio of the first and second sections of the filter screen have been optimized, which ensures the support performance while further improving flexibility. In conjunction with the setting of the imaging ring and the improvement of the weaving material, the visibility of the intracranial embolism protection device is better and it is easier to operate. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Figure 1 This is a schematic diagram of the overall structure of the intracranial embolism protection device;

[0021] Figure 2 This is a schematic diagram showing the length of the filter assembly;

[0022] Figure 3 This is a schematic diagram of the cross-section of the distal end of the guidewire;

[0023] Figure 4 This is a schematic diagram of the location and structure of the bending and shaping section of the guidewire;

[0024] Figure 5 This is a structural diagram of the first section of the filter screen;

[0025] Figure 6 This is a schematic diagram of the maximum mesh size at the second section of the filter screen;

[0026] Figure 7 This is a schematic diagram of an intracranial embolism protection device being inserted into a blood vessel. Detailed Implementation

[0027] The following description is only intended to disclose the present invention so that those skilled in the art can implement it. The embodiments in the following description are merely examples, and those skilled in the art will conceive of other obvious modifications. The basic principles of the present invention defined in the following description can be applied to other embodiments, modifications, improvements, equivalents, and other solutions that do not depart from the spirit and scope of the present invention.

[0028] An intracranial embolism protection device, such as Figure 1 It includes guide wire 1, a filter assembly connected to guide wire 1, and a developing ring.

[0029] The guidewire 1 is preferably 0.3556 mm or 0.4572 mm in diameter, and the overall length of the guidewire is 300 cm or 310 cm. The surface of the guidewire 1 has a polytetrafluoroethylene coating 11, which is used to increase the lubricity of the guidewire and reduce the frictional resistance of the guidewire as it passes through the catheter and blood vessel.

[0030] The distal end of guidewire 1 has a 3-10cm section with lower hardness than other parts. This section is a bending and shaping section, which can be bent in various shapes, such as "J", "S" and other irregular shapes, which is conducive to passing through various irregular blood vessels.

[0031] The distal end of the guidewire 1 has a bullet-shaped structure 12, which reduces the resistance of the guidewire as it passes through the catheter and blood vessel, and at the same time reduces damage to the patient's blood vessels.

[0032] The proximal end represents the direction closest to the operator during the surgical procedure, while the distal end represents the direction furthest from the operator during the surgical procedure.

[0033] The placement of the imaging rings facilitates observation of the position and release / retrieval status of the embolization protection device during surgical procedures. The imaging rings include a first imaging ring 2 and a second imaging ring 5. The two imaging rings are preferably made of the same material. The first imaging ring 2 and the second imaging ring 5 are inserted into the guidewire 1 and welded and fixed. The axes of the guidewire 1, the first imaging ring 2, and the second imaging ring 5 are on the same line. The first imaging ring is located at the proximal end of the embolization protection device, and the second imaging ring is located at the distal end of the embolization protection device, which is used to visualize and mark the position of the device in the blood vessel.

[0034] The filter assembly includes a first filter section 3 and a second filter section 4, such as... Figure 2The length L1 of the first section 3 of the filter screen is three times the length L2 of the second section 4 of the filter screen, which further ensures support and flexibility. The weaving density of the first section 3 of the filter screen is less than that of the second section 4 of the filter screen. The proximal end of the first section 3 of the filter screen is connected to the first developing ring 2 by welding, and its distal end is connected to the proximal end of the second section 4 of the filter screen by using ribs. The overall diameter of the second section 4 of the filter screen is radially reduced and closed in an arc shape. The distal end is welded to the second developing ring 5.

[0035] like Figure 5 The first section 3 of the filter screen includes an outer connecting rib 31 and a middle connecting rib 32. The middle connecting rib 32 is composed of several polygonal woven frames, which improves flexibility. It preferably adopts a rhomboid structure, which is derived from a rhomboid. The sharp corners of the rhomboid are rounded. The outer connecting rib 31 is composed of several arc-shaped woven frames, which mainly play a supporting role in maintaining the shape. It is set along the length of the filter screen, such as a semi-circular arc-shaped woven frame. The arc-shaped woven frame is connected to the polygonal woven frame. The outer diameter of the first section 3 of the filter screen gradually increases from the near end to the far end. The outer diameter at the maximum point is the same as the outer diameter of the second section 4 of the filter screen.

[0036] Optionally, the arc portion of the arc-shaped woven frame is tangent to the arc of the polygonal woven frame and is fixed by welding.

[0037] Optionally, one, two, or more external connecting bars 31 may be provided. When multiple external connecting bars 31 are provided, the middle connecting bars 32 are provided between adjacent external connecting bars 31.

[0038] The outer diameter of the second section 4 of the filter screen is 3-7mm. The second section 4 is woven from several metal braided wires, with the distal end of the braid closed in an arc shape. The diameter of the metal braided wires in the second section 4 is no greater than 0.032mm, and the mesh diameter of the second section 4 is smaller than that of the first section 3 of the filter screen. Figure 6 The length L3 of the adjacent nodes of the mesh at the largest point of the second section 4 of the filter does not exceed 130μm. The length of the adjacent nodes of the mesh in the second section 4 of the filter gradually decreases from the proximal end to the distal end. The second section 4 of the filter with this structure can adapt to blood vessels of various diameters and improve the capture rate of emboli.

[0039] like Figure 7 As shown, this is the configuration of the embolization protection device after complete deployment in the blood vessel. The maximum outer diameter of the second segment 4 of the filter is equal to the inner diameter 7 of the blood vessel. During the procedure, embolic fragments 6 flow with the blood and are captured and trapped by the second segment 4 module of the filter. When the embolization protection device retracts, it will carry the embolic fragments out of the blood vessel. The second segment 4 of the filter can capture embolic fragments with a diameter greater than 130 μm.

[0040] The first section 3 and the second section 4 of the filter screen use braided wires made of platinum-core nickel-titanium alloy. The characteristic of this material is that platinum is encased in a nickel-titanium alloy, with platinum accounting for no more than 40% of the cross-sectional area of ​​the entire metal braided wire. This ensures consistent developing effect throughout the entire device.

[0041] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are merely examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been shown and explained in the embodiments. Without departing from the stated principles, the implementation of the present invention may have any variations and modifications.

Claims

1. An intracranial embolism protection device, characterized in that: The filter assembly includes a guide wire (1) and a filter screen assembly connected to the guide wire (1). The filter screen assembly includes a first section (3) and a second section (4) of the filter screen. The first section (3) of the filter screen includes an outer connecting rib (31) and a middle connecting rib (32). The middle connecting rib (32) includes several polygonal braided frames. The outer connecting rib (31) includes several arc-shaped braided frames. The arc-shaped braided frames are connected to the polygonal braided frames. The proximal end of the second section (4) of the filter screen is connected to the first section (3) of the filter screen, and the distal end is arc-shaped and closed. The diameter gradually decreases from the proximal end to the distal end. The mesh diameter of the second section (4) of the filter screen is smaller than the mesh diameter of the first section (3) of the filter screen, and the length of adjacent nodes of the mesh of the second section (4) of the filter screen does not exceed 130 μm.

2. The intracranial embolism protection device according to claim 1, characterized in that: The filter assembly has developing rings installed on both sides.

3. The intracranial embolism protection device according to claim 1 or 2, characterized in that: The length ratio of the first section (3) of the filter to the second section (4) of the filter is 3:

1.

4. The intracranial embolism protection device according to claim 3, characterized in that: The length of adjacent nodes of the second segment (4) of the filter gradually decreases from the near end to the far end.

5. The intracranial embolism protection device according to claim 3, characterized in that: The first and second sections of the filter screen are made of the same material of metal braided wire.

6. The intracranial embolism protection device according to claim 3, characterized in that: The first section (3) and / or the second section (4) of the filter screen are made of woven wire made of platinum core nickel titanium wire.

7. The intracranial embolism protection device according to claim 6, characterized in that: The diameter of the braided wires in the second section (4) of the filter screen is ≤0.032mm.

8. The intracranial embolism protection device according to any one of claims 4-6, characterized in that: The guidewire (1) is provided with a bending and shaping part, and the hardness of the bending and shaping part is lower than the hardness of other parts of the guidewire (1).

9. The intracranial embolism protection device according to claim 8, characterized in that: The guide wire (1) has a polytetrafluoroethylene coating (11) on its surface.

10. The intracranial embolism protection device according to claim 9, characterized in that: The distal end of the guide wire (1) is configured as a bullet head structure (12).

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