Intracranial thrombectomy stent

Abstract

The application relates to an intracranial thrombus-removing stent, belonging to the field of neurovascular interventional device equipment. The device mainly comprises a funnel-shaped stent body, the distal end of which is provided with a large-diameter opening, the proximal end is provided with a small-diameter opening, and the distal end edge is inwardly closed; the head end of the stent body is outwardly turned and extended with at least three turning claws, the top end of each turning claw is fixed with a semispherical bushing, and a rotatable scraping member is embedded in the bushing; the circumferential diameter of the turning claw is larger than the maximum opening diameter of the stent body. When the thrombus is removed, a microcatheter passes through the thrombus, the stent is pushed forward to make the turning claw extend and pass over the thrombus, the microcatheter is withdrawn to release the stent, the turning claw is turned and unfolded, the scraping member scrapes the mural thrombus when the whole body is withdrawn, and the funnel-shaped body wraps the thrombus and is withdrawn as a whole. The stent makes the mesh-shaped body not contact the blood vessel wall, reduces the blood vessel injury, the scraping member can actively remove the mural thrombus and prevent the mural thrombus from escaping, and the thrombus-removing safety and success rate are improved.

Description

Technical Field

[0001] This invention relates to the field of neurovascular interventional devices. In particular, it relates to an intracranial thrombectomy stent. Background Technology

[0002] Acute ischemic stroke is a serious cerebrovascular disease that severely endangers human health, characterized by high incidence, high disability rate, and high mortality rate. Acute stroke caused by occlusion of large intracranial vessels is extremely dangerous, with a narrow time window for intravenous thrombolysis and a low rate of vascular recanalization. In recent years, mechanical thrombectomy devices, especially stent thrombectomy devices, have become the preferred method for treating large intracranial vessel occlusion.

[0003] Existing intracranial thrombectomy stents typically consist of a pusher, sheath, thrombectomy frame, and contrast agent. During thrombectomy, the stent is delivered to the thrombus site via a microcatheter, released to embed itself into the thrombus, and then withdrawn along with the thrombus back into the microcatheter or intermediate catheter for removal. However, existing thrombectomy stents are prone to thrombus fragmentation and escape to distal vessels during thrombus capture and removal due to insecure clamping, leading to new embolisms. This is especially true when navigating tortuous vessel segments, where the stent-thrombus fit decreases, increasing the risk of escape. The radial support design of the stent also struggles to balance effective thrombus capture with vessel protection: excessive support can cause intimal damage or even perforation, while insufficient support results in inadequate thrombus capture. Furthermore, during stent retrieval, the proximal opening or connection point may scrape the vessel wall.

[0004] Therefore, there is an urgent need for an intracranial thrombectomy stent and a corresponding thrombectomy method that can reduce thrombus escape, reduce vascular damage, and improve the success rate of thrombectomy. Summary of the Invention

[0005] The purpose of this invention is to provide an intracranial thrombectomy stent to solve one or all of the technical problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides the following solution: This invention provides an intracranial thrombectomy stent, disposed within a microcatheter, comprising: The stent body is funnel-shaped, with the end of the stent body closer to the opening of the microcatheter being the distal end and the end farther from the opening of the microcatheter being the proximal end. The distal end of the stent body has a large-diameter opening and the proximal end has a small-diameter opening, and the edge of the distal opening tapers inward. At least three flipping claws extend outward from the head end of the support body, and a hemispherical bushing is fixed to the top of each flipping claw. A rotatable scraper is embedded in the hemispherical bushing. The circumference diameter of the flipping claw is greater than the maximum opening diameter of the support body.

[0007] According to one embodiment of the present invention, the support body is a single-segment funnel structure; or, the support body is a multi-segment funnel structure, and the maximum diameter of the multi-segment funnel decreases sequentially from the distal end to the proximal end.

[0008] According to one embodiment of the present invention, the mesh portion of the support body is arranged in a sine curve, a cosine curve, or a straight line; the long axis distance of a single mesh is greater than the short axis distance, and the included angle between meshes is greater than 90° and less than 180°.

[0009] According to one embodiment of the present invention, the number of the flipping claws is three or more, and the flipping claws are made of shape memory alloy, tough metal material or polymer material; the flipping angle of the flipping claws is greater than 180° and less than 360°.

[0010] According to one embodiment of the present invention, the scraper is spherical, ellipsoidal, cylindrical, or bent cylindrical; the hemispherical bushing is made of metal or polymer material, and the scraper is made of metal.

[0011] According to one embodiment of the present invention, the surface of the scraper is a frosted surface.

[0012] According to one embodiment of the present invention, in the mesh portion of the support body, the mesh is denser closer to the large-diameter opening at the distal end.

[0013] A thrombectomy teaching method, using the aforementioned intracranial thrombectomy stent, includes the following steps: S1: The microcatheter is delivered to the thrombus in the intracranial vascular model via the guiding catheter and intermediate catheter, so that the microcatheter passes through the thrombus and reaches the distal end of the thrombus; S2: Advance the intracranial thrombectomy stent forward so that the flipping claw extends out of the microcatheter and passes over the thrombus; S3: Retract the microcatheter, release the stent body, and allow the flipping claw to flip, unfold, and conform to the blood vessel wall; S4: The intracranial thrombectomy stent and the microcatheter are retracted as a whole, so that the scraping piece on the flipping claw scrapes away the thrombus attached to the blood vessel wall, while the funnel-shaped stent body wraps the thrombus. S5: Remove the intracranial thrombectomy stent, the microcatheter, and the thrombus as a whole from the body.

[0014] According to one embodiment of the present invention, in step S4, when the intracranial thrombectomy stent and the microcatheter are withdrawn as a whole, the stent and the microcatheter are first withdrawn into the intermediate catheter, and then the intermediate catheter together with the stent and the microcatheter are withdrawn out of the body.

[0015] According to one embodiment of the present invention, before step S1, an angiography step is included to locate the thrombus; after step S5, a follow-up angiography step is included to evaluate the recanalization effect.

[0016] Beneficial effects This invention has at least one of the following technical effects: Firstly, in this invention, the circumferential diameter of the flipping claw is larger than the maximum opening diameter of the stent body, ensuring that the funnel-shaped mesh portion does not contact the blood vessel wall after release; only the scraping component at the tip of the flipping claw makes point-like contact with the blood vessel. Compared to existing stent designs where the entire mesh surface adheres to the blood vessel wall, this invention reduces the contact area by more than 90%, effectively avoiding the risk of mesh wires scratching the intima, inducing vascular spasm, or perforation. Simultaneously, the inward contraction of the distal opening further eliminates sharp edges, greatly improving surgical safety.

[0017] Secondly, the flipping claw unfolds outwards during retraction, and the scraping component at the tip of the claw rotates under force to actively scrape away thrombi attached to the vessel wall. At the same time, the funnel-shaped stent body catches the thrombus fragments from behind. This structure changes the traditional stent's mechanism of passively embedding and grabbing thrombi, effectively removing residual thrombi close to the vessel wall while preventing thrombi from fragmenting and escaping distally, significantly reducing the incidence of secondary embolism.

[0018] Thirdly, the large distal opening of the funnel-shaped stent fully covers the thrombus area, while the small proximal opening smoothly transitions to the push rod or microcatheter. During retrieval, the thrombus is compressed into the small opening, making it less likely to dislodge from the proximal end. The inward-curving distal edge design prevents the stent edge from scraping the vessel wall during retrieval. The overall structure conforms to the vessel's course, resulting in low retraction resistance and a high success rate for thrombectomy on the first attempt. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the intracranial thrombectomy stent. Figure 2 A diagram illustrating the usage status of an intracranial thrombectomy stent. Figure 1 ; Figure 3 A diagram illustrating the usage status of an intracranial thrombectomy stent. Figure 2 ; Figure 4 A diagram illustrating the usage status of an intracranial thrombectomy stent. Figure 3 ; Figure 5A diagram illustrating the usage status of an intracranial thrombectomy stent. Figure 4 ; Figure 6 This is a schematic diagram of the flipping claw part of the intracranial thrombectomy stent; Figure 7 A schematic diagram of the proportional structure of the flipping claw portion of the intracranial thrombectomy stent; Figure 8 This is a schematic diagram of the grid arrangement in the main body of an intracranial thrombectomy stent.

[0021] Explanation of reference numerals in the attached figures: Microcatheter 1; Stent body 2; Flip claw 3; Hemispherical bushing 31; Scraper 32; Intracranial vascular model X; Thrombus Y. Detailed Implementation

[0022] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and to exemplify the principles of the present invention, and are not configured to limit the present invention. In addition, the structural components in the drawings are not necessarily drawn to scale. For example, the dimensions of some structural components or regions in the drawings may be enlarged for other structural components or regions to aid in the understanding of the embodiments of the present invention.

[0023] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of the embodiments of the present invention. In the description of the present invention, it should be noted that, unless otherwise stated, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0024] Furthermore, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure or component that includes a list of elements includes not only those elements but also other structural elements that are not expressly listed or inherent to the structure or component. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the article or apparatus that includes the element.

[0025] Spatial relation terms such as "below," "under," "under," "low," "above," "on," and "high" are used for descriptive convenience to explain the positioning of one element relative to a second element, indicating that these terms are intended to cover different orientations of the device, in addition to those different from those shown in the figure. Furthermore, phrases such as "one element on / below another element" can indicate that two elements are in direct contact, or that there are other elements between the two elements. In addition, terms such as "first" and "second" are also used to describe individual elements, areas, parts, etc., without specifically indicating order or sequence, and should not be considered restrictive. Similar terms are used throughout the description to represent similar elements.

[0026] It will be apparent to those skilled in the art that the present invention can be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention.

[0027] In the following embodiments, descriptions such as "this device" may appear. Those skilled in the art should understand that "this device" refers to an intracranial thrombectomy stent provided by the present invention. The stent is pre-loaded into the microcatheter 1 before use. The stent includes a funnel-shaped stent body 2. The end of the stent body 2 closest to the opening of the microcatheter 1 is the distal end, and the end furthest from the opening of the microcatheter 1 is the proximal end. The distal end of the stent body 2 has a large-diameter opening, and the proximal end has a small-diameter opening. The edge of the distal opening is smoothly tapered inward to prevent the stent from scratching the vessel wall during deployment or retraction.

[0028] The main body 2 of the support extends outward from its distal end, extending outward with three flipping claws 3. The flipping claws 3 are formed by laser cutting of a nickel-titanium shape memory alloy tube and then heat-setting in a mold, with a flipping angle of 270°. Each flipping claw 3 has a hemispherical bushing 31 fixed to its tip by laser welding. The hemispherical bushing 31 is made of medical-grade stainless steel. Embedded within the hemispherical bushing 31 is a rotatable scraper 32, which is spherical and made of platinum with excellent imaging properties, with a sandblasted surface to create a frosted finish.

[0029] The circumferential diameter D of the rotating claw 3 is greater than the maximum opening diameter d of the support body 2. The mesh portion of the support body 2 is arranged in a sinusoidal curve, with the major axis distance L of a single mesh being greater than the minor axis distance W, and the included angle θ between meshes being 120°. In the mesh portion of the support body 2, the mesh is denser closer to the large-diameter opening at the far end.

[0030] The intracranial thrombectomy stent of this embodiment has self-expanding properties. When compressed within the microcatheter 1, both the flipping claw 3 and the stent body 2 are in a retracted state. After the microcatheter 1 is extended, the flipping claw 3 automatically flips and unfolds, and the stent body 2 automatically expands into a funnel shape.

[0031] In some embodiments, the stent body 2 is a multi-segment funnel structure. Specifically, the stent body 2 includes a first funnel segment, a second funnel segment, and a third funnel segment sequentially from distal to proximal. The maximum diameter of the three funnel segments decreases sequentially from distal to proximal, with the first funnel segment having the largest diameter, the second funnel segment the second largest, and the third funnel segment the smallest. This structure is particularly suitable for intracranial vessel segments where the vessel diameter gradually changes. After the stent is deployed, each funnel segment can conform to the vessel wall of its corresponding diameter, providing uniform radial support and preventing local collapse or over-dilation of a single funnel at the change in vessel diameter.

[0032] In the above embodiments, the multi-segment funnel structure can also be combined with changes in grid density: the funnel segment closer to the distal end has a denser grid to enhance the ability to encapsulate the thrombus Y; the funnel segment closer to the proximal end has a relatively sparser grid to reduce the overall metal coverage of the stent and reduce the impact on blood flow.

[0033] In one embodiment, the mesh portion is arranged in a sinusoidal pattern, with adjacent sinusoidal waveforms interlaced to form a continuous rhomboid or approximately parallelogram grid. This arrangement allows the stent to have a uniform stress distribution during radial compression and expansion, resulting in better flexibility and facilitating passage through tortuous blood vessels.

[0034] In another implementation, the mesh portion is arranged using cosine curves, the shape of its peaks and troughs being similar to that of sine curves, but with different phases, thus forming a regular mesh.

[0035] In another embodiment, the mesh portion is arranged in straight lines, meaning the mesh consists of multiple sets of longitudinal straight lines and transverse or diagonal connecting rods, forming a rectangular or trapezoidal mesh. This arrangement method is simpler to manufacture and has better tensile strength in the axial direction, which helps maintain the integrity of the shape when the entire support is retracted.

[0036] All the above arrangements satisfy the following conditions: the major axis spacing L of a single grid is greater than the minor axis spacing W, and the included angle θ between grids is greater than 90° and less than 180°. This parameter design ensures that the grid has sufficient opening area for the thrombus Y to enter, while preventing the thrombus Y from slipping out of the grid.

[0037] In some embodiments, the number of flipping claws 3 can be three, four, five, or six. Three flipping claws 3 are distributed at 120° intervals, which can form a stable three-point support within the blood vessel, minimizing the contact area and damage. Four flipping claws 3 are distributed at 90° intervals, providing more uniform support and are suitable for blood vessels with larger diameters. Five or six flipping claws 3 are suitable for extremely curved or complex diseased blood vessel segments, increasing the number of gripping points.

[0038] The materials for the flip claw 3 can be: nickel-titanium shape memory alloy, which utilizes its superelasticity and shape memory effect to automatically restore the preset flip angle at body temperature; cobalt-chromium alloy, which utilizes its good toughness to meet the requirement of high radial support force; medical stainless steel, which has low cost and good machinability; or biocompatible polymer materials, such as polyetheretherketone, which are suitable for non-permanent implantation or short-term use thrombectomy devices.

[0039] The flipping angle α of the flipping claw 3 is between 180° and 360°, preferably between 240° and 300°. When α = 180°, the flipping claw 3 flips just from axial to radial, and the tip of the scraper 32 contacts the blood vessel wall when it retracts; when α > 180°, the flipping claw 3 opens further outward, and the movement trajectory of the scraper 32 is closer to the blood vessel wall, thus enhancing the scraping effect; when α is close to 360°, the flipping claw 3 almost forms a closed loop, which provides better encapsulation of the thrombus Y, but the radial force may be larger, and the selection needs to be based on the strength of the blood vessel wall.

[0040] In some embodiments, the shape of the scraper 32 can be set as spherical, ellipsoidal, cylindrical, bent cylindrical, or other feasible structures, and the hemispherical bushing 31 is adaptively adjusted to follow the scraper 32 to ensure that the scraper 32 can fit inside the hemispherical bushing 31. The spherical scraper 32 is the most basic implementation. Its spherical structure has the same radius of curvature in all directions, so regardless of the angle at which the flipping claw 3 contacts the vessel wall, the contact between the spherical surface and the vessel wall is point contact, minimizing friction and reducing the risk of vessel damage. Simultaneously, the spherical scraper 32 can rotate in any direction within the hemispherical bushing 31. When the stent is retracted, the tangential force generated by the contact between the spherical body and the thrombus Y or the vessel wall drives the spherical body to roll, converting sliding friction into rolling friction and further reducing resistance. The spherical scraper 32 is suitable for all types of thrombi Y, especially fresh, soft thrombi Y. The rolling of the spherical body prevents it from cutting the thrombus Y, preserving its integrity.

[0041] The scraper 32 is ellipsoidal in shape, possessing a major axis and a minor axis. When the major axis of the ellipsoid aligns with the stent retraction direction, the contact area between the ellipsoid and the vessel wall is relatively small, resulting in a gentle scraping effect. When the major axis of the ellipsoid is perpendicular to the retraction direction, the ellipsoid contacts the thrombus Y with a longer arc surface, increasing the scraping area, which is suitable for firmly attached old thrombi Y. The ellipsoidal scraper 32 is rotatable within the bushing; therefore, during actual retraction, the ellipsoid automatically adjusts its posture according to the applied force, achieving a balance between reducing resistance and enhancing scraping force.

[0042] The scraper 32 is cylindrical and has an axial length. Its contact with the vessel wall is a line contact, not a point contact. Line contact provides a larger scraping area, resulting in stronger removal of mural thrombi Y. The ends of the cylindrical scraper 32 can be rounded to prevent scratching the vessel. The cylinder can rotate around its axis within the bushing. During retraction, the cylindrical surface rolls and rubs against the thrombus Y, effectively removing it without excessively compressing the vessel. The cylindrical scraper 32 is particularly suitable for vessel segments with irregular walls, as its longer contact line can cross the plaque surface, stably scraping away the thrombus Y.

[0043] The scraper 32 is a bent cylinder. While the main body of the scraper 32 is cylindrical, it has a bend in the middle. This bend design causes the outer contour of the scraper 32 to periodically change its contact point with the vessel wall as it rotates within the bushing, actively scraping away thrombi Y embedded in the folds of the vessel wall. Simultaneously, the bend increases the effective scraping width of the scraper 32, covering a larger circumferential area of ​​the vessel wall within the same dimensions. This shape is particularly suitable for calcified thrombi Y or thrombi Y tightly adhered to the vessel wall, significantly improving clearance rates.

[0044] In all embodiments with different shapes, the surface of the scraper 32 is frosted to obtain a micro-rough surface. The frosted scraper 32 has a significantly increased static friction coefficient with the thrombus Y, preventing the thrombus Y from slipping off the surface of the scraper 32. At the same time, the frosted surface also helps the scraper 32 to grasp the fragments of the thrombus Y and drag them into the funnel-shaped support body 2.

[0045] In some embodiments, the mesh is denser closer to the distal large-diameter opening and sparser closer to the proximal small-diameter opening. The purpose is that the dense mesh effectively intercepts and encapsulates the head of the thrombus Y at the distal large-diameter opening, preventing it from escaping through the mesh after fragmentation. The sparse mesh at the proximal opening helps maintain the overall flexibility of the stent, facilitating withdrawal through the curved intermediate catheter and guide tube. Simultaneously, the gradual change in mesh density also reduces the radial support force of the stent from distal to proximal, preventing excessive proximal support force that could damage the proximal vessel.

[0046] A thrombectomy teaching method using an intracranial thrombectomy stent as described in any of the above embodiments, which is particularly suitable for surgical skills training on human vascular models.

[0047] like Figure 2-5 As shown, the specific steps include: S1: The microcatheter 1 is delivered to the predetermined thrombus Y location in the intracranial vascular model X via the guiding catheter and intermediate catheter. The thrombus Y is located by angiography or simulated imaging. Then, the microcatheter 1 is pushed forward so that it passes through the thrombus Y and reaches the distal end of the thrombus Y.

[0048] S2: The intracranial thrombectomy stent pre-loaded in the guide sheath is inserted into the microcatheter 1 via a guidewire and advanced forward, causing the flipping claw 3 to extend beyond the distal opening of the microcatheter 1 and pass over the thrombus Y. At this time, the flipping claw 3 is still in the retracted state under the constraint of the microcatheter 1, but the claw tip has extended beyond the distal end of the thrombus Y.

[0049] S3: Keep the stent in place and slowly retract the microcatheter 1. As the microcatheter 1 is retracted, the flipping claw 3 is released from its constraint and automatically flips and unfolds, while the stent body 2 expands into a funnel shape. The scraping part 32 of the flipping claw 3 conforms to the simulated blood vessel wall of the blood vessel model, and the distal opening edge of the stent body 2 retracts inward without scratching the blood vessel wall.

[0050] S4: After the microcatheter 1 is completely withdrawn from the stent area, the operator slowly and evenly retracts the intracranial thrombectomy stent and microcatheter 1 as a whole towards the proximal end. During the retraction process, the scraper 32 on the flipper 3 comes into contact with the simulated thrombus Y on the simulated blood vessel wall. The scraper 32 rotates and scrapes off the attached thrombus Y. At the same time, the funnel-shaped stent body 2 catches the scraped thrombus Y fragments from the rear to prevent them from escaping distally.

[0051] S5: Continue withdrawal, retracting the stent and microcatheter 1 as a whole into the intermediate catheter, and then withdrawing them out of the body together with the intermediate catheter. Finally, a simulated angiography can be performed to assess the thrombus clearance effect.

[0052] In step S4, if the simulated resistance increases, it indicates that the thrombus Y has been effectively clamped. The retraction speed can be appropriately slowed down, or negative pressure can be drawn back from the side of the guide tube to help the thrombus Y enter the intermediate catheter.

[0053] This teaching method can be repeated. By operating life-size stents and blood vessel models, trainees can intuitively understand the unfolding process of the flipper 3, the interaction between the scraper 32 and the blood vessel wall, and the thrombus Y-encapsulation mechanism of the funnel-shaped stent. Different shapes of scrapers 32 can be used during the teaching process to compare the removal effects of different scrapers 32 on the simulated thrombus Y, thus deepening the understanding of the device design.

[0054] It should be understood that the above-described embodiments or examples of the present invention can be combined with each other and have corresponding technical effects.

[0055] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An intracranial thrombectomy stent, disposed within a microcatheter (1), characterized in that, include: The stent body (2) is funnel-shaped. The end of the stent body (2) closer to the opening of the microcatheter (1) is the distal end, and the end farther from the opening of the microcatheter (1) is the proximal end. The distal end of the stent body (2) has a large diameter opening, and the proximal end has a small diameter opening. The edge of the distal opening tapers inward. At least three flipping claws (3) extend outward from the head end of the support body (2), and a hemispherical bushing (31) is fixed at the top of each flipping claw (3). A rotatable scraper (32) is embedded in the hemispherical bushing (31). The circumferential diameter of the flipping claw (3) is greater than the maximum opening diameter of the support body (2).

2. The intracranial thrombectomy stent according to claim 1, characterized in that, The support body (2) is a single-segment funnel structure; or, the support body (2) is a multi-segment funnel structure, and the maximum diameter of the multi-segment funnel decreases sequentially from the distal end to the proximal end.

3. The intracranial thrombectomy stent according to claim 1, characterized in that, The mesh portion of the support body (2) is arranged in a sine curve, a cosine curve, or a straight line.

4. The intracranial thrombectomy stent according to claim 3, characterized in that, The major axis distance of a single grid is greater than the minor axis distance, and the included angle between grids is greater than 90° and less than 180°.

5. The intracranial thrombectomy stent according to claim 1, characterized in that, The number of the flipping claws (3) is three or more, and the flipping claws (3) are made of shape memory alloy, tough metal material or polymer material.

6. The intracranial thrombectomy stent according to claim 5, characterized in that, The flipping angle of the flipping claw (3) is greater than 180° and less than 360°.

7. The intracranial thrombectomy stent according to claim 1, characterized in that, The scraper (32) is spherical, ellipsoidal, cylindrical, or bent cylindrical.

8. The intracranial thrombectomy stent according to claim 7, characterized in that, The hemispherical bushing (31) is made of metal or polymer material, and the scraper (32) is made of metal material.

9. The intracranial thrombectomy stent according to claim 1, characterized in that, The surface of the scraper (32) is a frosted surface.

10. The intracranial thrombectomy stent according to claim 1, characterized in that, In the mesh portion of the support body (2), the mesh is denser closer to the large-diameter opening at the far end.

Images