CN109998749B

CN109998749B - Intracranial vascular stent with distal protection

Info

Publication number: CN109998749B
Application number: CN201910295754.7A
Authority: CN
Inventors: 张长东
Original assignee: Wuhan Weike Medical Technology Co ltd
Current assignee: WUHAN WEIKE MEDICAL TECHNOLOGY Co.,Ltd.
Priority date: 2019-04-12
Filing date: 2019-04-12
Publication date: 2021-07-30
Anticipated expiration: 2039-04-12
Also published as: CN109998749A

Abstract

The invention discloses an intracranial vascular stent with remote protection, wherein a stent mesh part, a first filtering part and a second filtering part are respectively of a net structure, and the mesh sizes of the stent mesh part, the first filtering part and the second filtering part are in proportion as follows: 5-20:3-4:0.5-2. The open end of the conical structure of the first filtering part and one end part of the net part of the support are integrally formed, the second filtering part is also in a conical structure, the middle part of the upper end of the second filtering part and the reducing end of the first filtering part are integrally formed, and the net part of the support, the first filtering part and the inner cavity of the second filtering part are in conduction connection. The intracranial vascular stent with the distal protection not only realizes the filtering effect on tiny emboli, but also reduces the obstruction to blood flow, and ensures that the influence on the blood supply balance of a patient can be reduced as much as possible when the treated patient uses the intracranial vascular stent. Further realize encephalic vascular support filtration many times to can satisfy the more preceding effect of filtering at every turn, avoid once filtering to lead to the vascular circulation to receive the influence.

Description

Intracranial vascular stent with distal protection

Technical Field

The invention relates to the technical field of structural design of a bracket for treatment of intracranial vascular stenosis patients, in particular to an intracranial vascular bracket with a distal end protection function.

Background

Atherosclerotic stenosis of major intracranial arteries, such as the carotid siphonic segment, the Middle Cerebral Artery (MCA), the vertebral artery, and the basilar artery, is an important cause of ischemic stroke, particularly in the black, asian, and hispanic population. Intracranial arterial stenosis in the united states causes approximately 50000 ischemic strokes per year.

The research carried out in the 60 s of the 20 th century first clarified the importance of atherosclerotic intracranial aortic occlusive disease as the cause of stroke. One of the largest studies, the extracranial arterial occlusion combination study, evaluated 3788 patients with symptoms and signs of ischemic cerebrovascular disease using 4 angiograms (84% of them were white).

In all patients 6.1% of the presence of simple intracranial occlusive disease was observed

Stenosis is present in 7.7% of basilar arteries, 4.4% of intracranial vertebral arteries, 6.7% of intracranial carotid arteries, 3.8% of MCA, 3.2% of Anterior Cerebral Arteries (ACAs) and 2.6% of Posterior Cerebral Arteries (PCA).

Subsequent studies have demonstrated that approximately 5% -10% of white human ischemic strokes are caused by intracranial arterial stenosis. These studies are likely to underestimate the true incidence of intracranial arterial stenosis as the cause of stroke, as only 38% -75% of patients have undergone angiography (the most reliable method of demonstrating intracranial arterial stenosis).

An analysis of the data from the WASID study showed that the risk factors for intracranial arterial stenosis were more prevalent than those of other stroke subtypes, and that the history of dyslipidemia was independently associated with severe intracranial arterial stenosis (OR 1.62, 95% CI 1.09-2.42).

In patients with symptomatic intracranial arterial stenosis, the subsequent stroke usually occurs in the non-lacunar region where symptomatic arteries supply blood, with a high proportion of disability. The WASID cohort had an average follow-up of 1.8 years, resulting in a total of 106 ischemic strokes. Stroke in 77 patients (73%) occurred in symptomatic stenotic arterial supply; of these 77 stroke patients, 70 (91%) were non-lacunar stroke and 34 (44%) were disabled.

Stenting — non-random prospective and enrollment studies with bare metal stents (NEUROLINK and Wingspan) provide encouraging data in terms of safety and potential efficacy of stenting for intracranial arterial stenosis. However, the only randomized study (i.e., SAMMPRIS) found that patients treated with angioplasty and stenting had a significantly higher incidence of 30-day stroke or death than those patients receiving only medical treatment.

In the existing stent operation treatment process, in the supporting process of the narrow position of an intracranial blood vessel, the tiny embolus of the unstable plaque at the narrow position is easy to fall off, and the 'stroke' cerebral infarction can be caused by the falling of the tiny embolus. The support in the prior art does not have a structure capable of avoiding the falling of the tiny embolus, so that the secondary injury is caused to a patient in the treatment process.

Therefore, in the prior art, in the intracranial vascular stenosis treatment process, the micro embolus is easy to fall off, so that the patient is caused with 'stroke' cerebral infarction.

Disclosure of Invention

In view of the above, the main object of the present invention is to provide an intracranial vascular stent with a distal protection, which not only achieves a filtering effect on tiny emboli, but also reduces the obstruction to blood flow, and ensures that the influence on the blood supply balance of a patient can be reduced as much as possible when the intracranial vascular stent is used by the patient to be treated. Further realize encephalic vascular support filtration many times to can satisfy the more preceding effect of filtering at every turn, avoid once filtering to lead to the vascular circulation to receive the influence.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

an intracranial vascular stent with distal protection, comprising: support net portion, first filter house and second filter house, support net portion, first filter house and second filter house integrated into one piece in proper order.

In a preferred embodiment, the stent mesh part, the first filter part and the second filter part are respectively in a net structure, and the ratio of the mesh sizes of the stent mesh part, the first filter part and the second filter part is as follows: 5-20:3-4:0.5-2.

In a preferred embodiment, support net portion outer wall is cylindric structure, first filter house is the toper structure, just the conical structure opening end and the support net portion an end integrated into one piece of first filter house, the second filter house also is conical structure, second filter house upper end middle part and the throat end integrated into one piece of first filter house, just support net portion, first filter house and the inside cavity of second filter house are in turn-on connection.

The intracranial vascular stent with distal protection is characterized in that the second filter part comprises: the filter comprises a conical outer wall with a conical structure, a beam opening end of a necking end seal of the conical outer wall and a filter end at an opening end of the conical outer wall; a fixing groove is arranged at the junction position between the filtering end and the outer wall of the cone, and the fixing groove surrounds the edge of the open end part of the outer wall of the cone;

in a preferred embodiment, the conical outer wall is fixedly connected with a filter membrane, one end part of the filter membrane is embedded and fixed in the fixing groove, and the other end of the filter membrane is fixed with the beam opening end.

The intracranial vascular stent with the distal protection is characterized in that the filtering end is of a groove-shaped structure.

The intracranial vascular stent with the distal end protection is characterized in that the middle of the groove-shaped structure is connected with the first filtering part, so that the end part of the filtering part is in an annular groove structure.

The intracranial vascular stent with the distal protection is characterized in that the end part of the first filter part is provided with a first marking ring.

The intracranial vascular stent with the distal protection is characterized in that the beam opening end of the second filtering part is provided with a second marking ring.

The intracranial vascular stent with the distal protection is characterized in that the fixing groove is uniformly provided with at least three third marking rings.

The intracranial vascular stent with the distal protection is characterized by further comprising: and the third filtering part has the same structure as the second filtering part, and the middle part of the third filtering part is fixedly connected with the beam opening end of the second filtering part.

The intracranial vascular stent with the distal protection is characterized in that the stent mesh part, the first filtering part, the second filtering part and the third filtering part are all formed by weaving titanium-nickel alloy wires.

The intracranial vascular stent with the distal protection is characterized in that the mesh size ratio of the stent mesh part, the first filter part and the second filter part is as follows: 10:3:1.

The intracranial vascular stent with the distal protection has the following beneficial effects:

the intracranial vascular stent with the distal protection comprises: the filter comprises a bracket net part, a first filter part and a second filter part, wherein the bracket net part, the first filter part and the second filter part are sequentially and integrally formed; support net portion, first filter house and second filter house are network structure respectively, and the proportion of support net portion, first filter house and second filter house mesh size is: 5-20:3-4: 0.5-2; support net portion outer wall is cylindric structure, and first filter house is the toper structure, just the conical structure opening end and support net portion an end integrated into one piece of first filter house, second filter house also are conical structure, second filter house upper end middle part and the throat end integrated into one piece of first filter house, and support net portion, first filter house and the inside cavity of second filter house are in the turn-on connection. The bracket solves the problems that in the prior art, the generated tiny embolus can not be filtered in the use process of the intracranial vascular bracket, and medical accidents such as apoplexy and the like easily occur in the use process of the bracket by a patient. The intracranial vascular stent with the distal protection not only realizes the filtering effect on tiny emboli, but also reduces the obstruction to blood flow, and ensures that the influence on the blood supply balance of a patient can be reduced as much as possible when the treated patient uses the intracranial vascular stent. Further realize encephalic vascular support filtration many times to can satisfy the more preceding effect of filtering at every turn, avoid once filtering to lead to the vascular circulation to receive the influence.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a front view of an intracranial vascular stent with distal protection according to one embodiment of the present disclosure;

FIG. 2 is a cross-sectional view of an intracranial vascular stent with distal protection according to one embodiment of the present disclosure;

FIG. 3 is an enlarged partial view of a second filter portion of the intracranial vascular stent with distal protection of FIG. 2 according to one embodiment of the disclosure;

FIG. 4 is an enlarged partial view of FIG. 3 at A in a second filter portion of a distally protected intracranial vascular stent according to one embodiment of the disclosure;

fig. 5 is a cross-sectional view of an intracranial vascular stent with distal protection according to another embodiment of the present disclosure.

[ description of main reference symbols ]

1. A first filter unit;

2. the second filtering part 21, the conical outer wall 22, the beam opening end 23, the filtering end 24, the fixing groove 25 and the fixing bulge;

3. a third filtering part 4, a bracket net part;

51. a first marker ring, 52, a second marker ring.

Detailed Description

The intracranial vascular stent with distal protection of the invention is further described in detail with reference to the accompanying drawings and the embodiment of the invention.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

For ease of description, spatially relative terms such as "above … …"),

"above … …", "on … …", "above", and the like, are used to describe one device or feature as it appears in the figures in relation to another device or feature in spatial position. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

As shown in fig. 1, fig. 2, fig. 3 and fig. 4, the intracranial vascular stent with distal protection comprises: a stent net part 14 which mainly supports the narrow position of the intracranial blood vessel and ensures that the blood vessel cavity can sufficiently meet the blood flow; a first filter unit 1 downstream of the stent mesh unit 14 for filtering blood passing through the stent mesh unit 14; and a second filtering part 2 which is arranged at the lower part of the first filtering part 1 and is used for filtering the blood filtered by the first filtering part 1 and the blood flowing into the second filtering part 2 along the cavity in the middle of the first filtering part 1. In order to ensure the connection tightness among the stent mesh part 4, the first filtering part 1 and the second filtering part 2 and avoid the mutual connection position structure size being larger, which is inconvenient for intervention operation in intracranial blood vessels, preferably, the stent mesh part 4, the first filtering part 1 and the second filtering part 2 are sequentially and integrally formed.

In order to reduce the obstruction to the blood flow and ensure that the treated patient can reduce the influence on the blood supply balance of the patient as much as possible during the process of using the intracranial vascular stent. The support net part 4, the first filter part 1 and the second filter part 2 are respectively designed into a net structure. The support net part 4 is of a net structure, so that the support effect on intracranial blood vessels can be ensured, and in the support effect on the intracranial blood vessels, tiny emboli on the inner wall of the intracranial blood vessels are likely to fall off, and the tiny emboli enter the support net part 4 through the net structure due to the large mesh size of the support net part 4. Further, the micro embolus enters the blood vessel after double filtration by the first filter unit 1 and the second filter unit 2, and is supplied for use. The micro embolus is prevented from entering cerebral vessels of a human body, the health of the human body is ensured, and the occurrence of stroke accidents is avoided.

In order to realize multiple times of filtration of the intracranial vascular stent, further fine filtration of each filtration effect can be met, and the influence on blood vessel circulation caused by one-time filtration, influence on blood supply of brain of a human body and further influence on normal life of the human body can be avoided. The mesh sizes of the stent mesh part 4, the first filter part 1 and the second filter part 2 are designed as follows: 5-20:3-4:0.5-2. Preferably, the ratio of the mesh sizes of the stent mesh part 4, the first filter part 1 and the second filter part 2 is as follows: 10:3:1.

The support net part 4 ensures that the support effect on the intracranial blood vessel is realized, and ensures that the mesh is large enough, so that all tiny emboli in the intracranial blood vessel can smoothly enter the support net part 4. The mesh sizes of the first filtering part and the second filtering part 2 are decreased progressively, so that the effect of double filtering is ensured. Through first filter house 1 filtration and drainage, with the drainage of great small embolus along cavity department, the small embolus can pass first filter house 1 and then get into second filter house 2 once more and realize the filtration.

Preferably, the outer wall of the stent net part 4 is in a cylindrical structure (ensuring a longer supporting area), and the upstream end of the stent net part 4 is in a necking structure, so that the inner wall of an intracranial blood vessel is prevented from being punctured.

Further, in order to realize the better drainage and filtration dual function of first filter house 1, first filter house 1 is the toper structure, and the conical structure opening end of

first filter house

1 and 4 tip integrated into one piece of support net part, second filter house 2 also is conical structure (make the storage of small embolus at the lower reaches tip of circular cone, can satisfy the effect of continuing the filtration to blood (mainly satisfy the circulation effect of blood) in other positions of conical structure, it is wider to avoid small embolus at distribution area, to the mesh jam of 2 each positions of second filter house, in addition form the thrombus easily, influence the blood circulation). The middle part of the upper end of the second filtering part 2 and the necking end of the first filtering part 1 are integrally formed, and the inner cavities of the support net part 4, the first filtering part 1 and the second filtering part 2 are in conduction connection. Namely: in the specific filtering process, tiny emboli falling from the stent mesh part 4 enter the stent mesh part 4; among the micro emboli, the small volume micro emboli can pass through the filtering holes of the first filtering portion 1, so that the first filtering portion 1 has a small blocking effect on the blood flow; the small emboli having a large volume cannot pass through the filtration pores of the first filtration part 1 and flow into the second filtration part 2 along the cavity inside the first filtration part 1, thereby further reducing the effect of blocking the flow of blood. Because the filtration pore (that is, the mesh) of second filter house 2 is further less than the aperture of first filter house 1, can further filter the effect to the tiny embolus in the blood, avoid tiny embolus to get into patient's brain, cause accidents such as patient apoplexy. The filtering holes of the second filtering part 2 are safe filtering holes, so that the filtering effect as far as possible can be realized by small emboli which cause harm to human bodies.

In order to ensure better filtering effect on blood, the defect that micro emboli enter the brain of a patient and cause stroke of the patient is further reduced. The second filter portion 2 includes: the blood is filtered, and the micro embolus is guided to be deposited on the conical outer wall 21 of the conical structure at the necking end of the conical second filtering part 2; sealing the second filter house 2 at the most downstream position of the second filter house 2, further allowing most of the tiny emboli to settle there and being the mouth end 22 of the mouth end seal of the conical outer wall; and a filtering end 23 at the open end of the conical outer wall 21, which filters blood that has been filtered by the first filtering portion 1, passes through the filtering holes of the first filtering portion 1, and performs a filtering action again when passing through the second filtering portion 2. The size of the filtering hole of the filtering end 23 is smaller than that of the filtering hole of the first filtering part 1, so that the filtering end 23 realizes the second filtering function.

In order to facilitate the marking of the position of the second filter house 2 and to achieve a guarantee that the higher strength of the second filter house 2 is increased. A fixing groove 24 is arranged at the boundary position between the filtering end 23 and the conical outer wall 21, and the fixing groove 24 surrounds the edge of the open end of the conical outer wall 21; the holding groove 24 may be a folded groove of the filter end 23, i.e.: when the filter end 23, the holding groove 24 and the conical outer wall 21 are in the stretched and compressed states, the holding groove 24 and the filter end 23 and the conical outer wall 21 are on a cylindrical surface. Therefore, the whole blood vessel stent can be compressed to a smaller volume in the interventional operation process, and the damage to the blood vessel of a patient is reduced. In order to ensure the filtering effect of the second filtering part 2, a filtering membrane is fixedly connected to the conical outer wall 21, one end of the filtering membrane is embedded and fixed in the fixing groove 24, and the other end of the filtering membrane is fixed with the beam-opening end 22.

Preferably, the filter membrane can be a PU filter membrane. One end part of the filtering membrane is fixed through the fixing groove 24, and the other end of the filtering membrane is fixed through the beam opening end 22, so that the fixing strength of the filtering membrane is ensured, medical accidents caused by falling of the filtering membrane are avoided, and the use safety of the intracranial intravascular stent is ensured.

In order to improve the filtering effect of the filtering end 23, the filtering end 23 is designed to be a groove-shaped structure. Thereby make the realization to small embolus guide effect, avoid small embolus to flow between circular cone outer wall and blood vessel inner wall, lead to the filter effect to small embolus to descend. The tiny emboli filter at the bottom of the groove and then enter the inner cavity of the second filter part 2. Preferably, the filtering hole size of the filtering end 23 is smaller than that of the first filtering portion 1 and larger than that of the conical outer wall 21. Thereby further increased the filterable position of tiny embolus, and then reduced the tiny embolus that every filter surface depositd to reduce the possibility of thrombus formation (avoid tiny embolus to gather a department and block up the filtration pore and influence blood circulation), reduce the influence to inside blood pressure balance of patient's health and blood supply, guarantee patient's comfort level.

In order to further make the tiny emboli precipitated at various positions uniformly precipitate, namely: the annular direction of the filtering part is uniform, and at each cross section, the tiny embolus is positioned at the lowest point of the groove, so that the blood can uniformly pass through the groove. Namely: the middle part of the groove-shaped structure is connected with the first filtering part 1, so that the filtering end 23 is in an annular groove structure. Preferably, the central position of the groove-shaped structure is connected with the first filtering part 1, so that the cavity formed between the first filtering part 1 and the inner wall of the intracranial blood vessel is uniform, the tiny embolus precipitated at each position is the same, and the defect that the tiny embolus is too concentrated to block the filtering end 23 is reduced.

To facilitate the intervention, the position of the intracranial vascular stent in the vessel is observed by a contrast technique. Preferably, a first marking ring 51 is provided at an end of the first filter part 1, and the first marking ring 51 is provided at a connecting position of the first filter part 1 and the second filter part 2. The binding end of the second filter part 2 is provided with a second marking ring 52, which not only realizes the marking function, but also can bind the second filter part 2, thereby the tiny embolus can filter in the second filter part 2.

The fixing groove 24 is uniformly provided with at least three third marking rings. Preferably, the fixing groove 24 is uniformly provided with 6 third marking rings (here, "ring" does not represent a ring shape, but is only for the purpose of corresponding names of the first marking ring 51 and the second marking ring 52); the third marking ring is of a sheet structure and is embedded into the fixing groove 24 and is fixed by the groove wall of the fixing groove 24. Further, a third fixing ring, preferably, a side near the filtering end 23 is fixedly connected to the inner wall of the fixing groove 24. The size of the fixing groove 24 is prevented from being too large in the process of interventional operation, the fixing groove 24 can be straightened, the filtering end 23, the fixing groove 24 and the conical outer wall 21 are all on the same cylindrical surface, the size of the intracranial vascular stent capable of being compressed to a greater extent in the diameter direction is large, and damage to blood vessels of a patient in the process of interventional operation is reduced. And also satisfies the stent operation of thinner blood vessels.

As shown in fig. 1, fig. 2, fig. 3, fig. 4 and fig. 5, in order to further filter the tiny emboli in the pocket bottom and further protect the blood vessels of the patient, the danger of stroke caused by the tiny emboli is avoided. Of course, the filtering pore size of the second filtering portion 2 may be set to be larger than that of the third filtering portion 3, so that the filtering pressure of the second filtering portion 2 is reduced and the third filtering portion 3 can completely filter the micro-emboli. The intracranial vascular stent further comprises: the third filtering part 3, the third filtering part 3 and the second filtering part 2 have the same structure, and the middle part of the third filtering part 3 is fixedly connected with the beam opening end 22 of the second filtering part 2.

Preferably, the support net part 4, the first filter part 1, the second filter part 2 and the third filter part 3 are integrally formed, woven and formed in a thermoplastic mode.

Furthermore, a plurality of fixing protrusions 25 are formed on the outer walls of the conical outer walls 21 of the second filter part 2 and the third filter part 3 at the ends close to the filter ends 23. The fixing protrusions 25 are preferably conical protrusions, and a plurality of fixing protrusions 25 are uniformly arranged around the conical outer wall 21, and preferably, 6 to 8 fixing protrusions 25 are uniformly arranged. And the included angle between the fixing projection 25 and the conical central line of the second filter part 2 is 10-20 degrees. After the stent is installed in an interventional manner, due to the blood flowing effect, if the whole intracranial vascular stent is pushed to slide, the friction between the protruding end part of the fixing protrusion 25 and the intracranial blood vessel is increased, even the fixing protrusion 25 is embedded into the inner wall of the blood vessel, so that the intracranial blood vessel is in a fixed state, and the safety of a patient using the stent is ensured.

Preferably, the stent mesh part 4, the first filtering part 1, the second filtering part 2 and the third filtering part 3 of the intracranial vascular stent are integrally woven by titanium-nickel alloy wires. Ensuring the weaving and shaping functions of the bracket.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.

Claims

1. An intracranial vascular stent with distal protection, comprising: the filter comprises a support net part (4), a first filter part (1) and a second filter part (2), wherein the support net part (4), the first filter part (1) and the second filter part (2) are sequentially and integrally formed;

support net portion (4), first filter house (1) and second filter house (2) are network structure respectively, support net portion (4), first filter house (1) and the proportion of second filter house (2) mesh size do: 5-20:3-4: 0.5-2;

the outer wall of the support net part (4) is of a cylindrical structure, the first filtering part (1) is of a conical structure, an open end of the conical structure of the first filtering part (1) and one end part of the support net part (4) are integrally formed, the second filtering part (2) is also of a conical structure, and cavities in the support net part (4), the first filtering part (1) and the second filtering part (2) are in conduction connection;

the second filter part (2) comprises: a cone outer wall (21) of a cone structure, a beam opening end (22) of a necking end seal of the cone outer wall and a filtering end (23) at an opening end of the cone outer wall (21); a fixing groove (24) is formed at the junction position of the filtering end (23) and the conical outer wall (21), and the fixing groove (24) surrounds the edge of the open end of the conical outer wall (21);

the conical outer wall (21) is fixedly connected with a filtering membrane, one end part of the filtering membrane is embedded and fixed in the fixing groove (24), and the other end of the filtering membrane is fixed with the beam opening end (22);

the middle part of the filtering end of the second filtering part (2) and the first filtering part (1) are integrally formed, so that the filtering end (23) is of an annular groove structure.

2. The intracranial vascular stent with distal protection according to claim 1, wherein the first filtering portion (1) is provided at its end with a first marker ring (51).

3. The intracranial vascular stent with distal protection according to claim 1, wherein the mouth end of the second filter portion (2) is provided with a second marker ring (52).

4. The intracranial vessel stent with distal protection according to claim 1, wherein the fixation slots (24) are uniformly provided with at least three third marker rings.

5. The intracranial vascular stent with distal protection as recited in claim 1, further comprising: the third filtering part (3) is identical to the second filtering part (2) in structure, and the middle of the third filtering part (3) is fixedly connected with a beam opening end (22) of the second filtering part (2).

6. The intracranial vascular stent with distal protection according to claim 5, wherein the stent mesh part (4), the first filter part (1), the second filter part (2), and the third filter part (3) are all braided by titanium-nickel alloy wires.

7. The intracranial vascular stent with distal protection according to claim 1, wherein the ratio of the mesh sizes of the stent mesh part (4), the first filter part (1) and the second filter part (2) is: 10:3:1.