A self-expanding vascular stent dedicated to cerebrovascular occlusion lesions

Abstract

The present invention relates to the field of medical devices, and specifically to a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions, which includes a plurality of self-expanding segments; any one of the self-expanding segments is respectively arranged in a ring shape, and the inner cavities of two adjacent self-expanding segments communicate with each other; the axial two ends of any one of the self-expanding segments are respectively a head end and a tail end, and in two adjacent self-expanding segments, a preset distance is left between the tail end of one of the self-expanding segments and the head end of the other self-expanding segment; a movable and inseparable connection structure is formed between two adjacent self-expanding segments through a connecting component. By setting a preset distance between two adjacent self-expanding segments, the effect of reducing or avoiding mutual extrusion of the two self-expanding segments is produced.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and specifically to a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions. Background Art

[0002] In the prior art, a patent document with the title of "Vascular Stent for Aneurysm at the Bifurcation of Cerebral Arteries" and application number 201520538028.0 is provided; the overall structure of this vascular stent adopts a common mesh structure and is specifically made by weaving or laser cutting processes.

[0003] In the prior art, a patent document with the title of "Self-expanding Drug-coated Vascular Stent" and application number 202121238234.1 is also provided; the overall structure of this vascular stent adopts a network tube structure, and among them, adjacent two main bars are connected by connecting bars.

[0004] When the vascular stents provided by the above two prior arts are actually applied to blood vessels with a relatively large curvature, for example: applied to the intracranial segment of the carotid artery (see Figure 14 ), the intracranial segment of the carotid artery is a cerebrovascular with multiple bending parts (see Figure 14 C2 - C7 in

[0005] Due to the limitation of the bending parts of the blood vessels, the above two vascular stents in the prior art objectively produce bending. At this time, since the above two vascular stents are actually integral stents, when the above two vascular stents are bent, the inner arc part of the bending part is subjected to two axial forces from both ends of the vascular stent to the inner arc part, and also subjected to a circumferential force from the outer arc part to the inner arc part of the vascular stent. Therefore, the above two vascular stents will inevitably produce a deformation 'from the inner arc part to the outer arc part direction' at the inner arc part, and further cause the inner diameter of the bending part of the above two vascular stents to become smaller, affecting blood flow. Summary of the Invention

[0006] To solve the technical problem in the prior art of how to reduce or avoid the deformation of the inner arc part of the vascular stent in the prior art towards the inside of the vascular stent at its bending part, the present invention provides a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] According to one aspect of the present invention, there is provided a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions, including a plurality of self-expanding segments;

[0009] Any one of the self-expanding segments is respectively arranged in a ring shape, and the inner cavities of two adjacent self-expanding segments communicate with each other;

[0010] The axial two ends of any one of the self-expanding segments are respectively a head end and a tail end. In two adjacent self-expanding segments, a preset distance is left between the tail end of one of the self-expanding segments and the head end of the other self-expanding segment;

[0011] Two adjacent self-expanding segments form a movable and inseparable connection structure through a connecting component.

[0012] Further, the connecting component is specifically a connecting wire;

[0013] The connecting wire connects at least two of the self-expanding segments, and the connecting wire is made of a metal material or a non-metal material. Wherein, the two ends of the connecting wire are welded together.

[0014] Further, the circumferential parts of any one of the self-expanding segments are respectively a mesh circumferential part, and a plurality of mesh holes are arranged in the mesh circumferential part. A deformable positioning ring is arranged at at least one of the mesh holes, and the connecting wire is restricted between the mesh circumferential part and the positioning ring.

[0015] Further, the positioning ring has a squeezed state and a natural state. When the positioning ring is in the natural state, a connection gap is formed between the surface where the positioning ring is located and the outer surface of the mesh circumferential part along the radial direction of the self-expanding segment, and the connection gap is used for the connecting wire to penetrate through.

[0016] Further, the number of the connecting wires is multiple. Wherein, there is and only one connecting wire between two adjacent self-expanding segments;

[0017] Any one of the self-expanding segments is respectively provided with at least two of the connection gaps, and all the connection gaps of two adjacent self-expanding segments are respectively penetrated by the same connecting wire.

[0018] Further, the number of the connecting wires is set to be one and only one;

[0019] Any one of the self-expanding segments is respectively provided with at least two of the connection gaps, and all the connection gaps of all the self-expanding segments are penetrated by the connecting wire.

[0020] Further, along the axial direction of the self-expanding segment, the positioning ring and the self-expanding segment form two axial connection points;

[0021] Or, along the circumferential direction of the self-expanding segment, the positioning ring and the self-expanding segment form two circumferential connection points.

[0022] Further, the self-expanding section is made of shape memory wires by a braiding process, wherein the positioning ring is a part of the shape memory wires;

[0023] Alternatively, the self-expanding section is made of a shape memory tube by a laser cutting process, wherein the positioning ring is a part of the shape memory tube.

[0024] Further, it further includes a coating layer;

[0025] The self-expanding section has an inner surface and an outer surface. The coating layer is arranged in a sleeve shape and is located in the inner cavities of multiple self-expanding sections, and the coating layer is closely attached to the inner surfaces of multiple self-expanding sections.

[0026] Further, it further includes a shell tube;

[0027] The self-expanding section has an expanded state and a contracted state. When the self-expanding section is located inside the shell tube, the self-expanding section is in the contracted state. When the self-expanding section is located outside the shell tube, the self-expanding section changes from the contracted state to the expanded state.

[0028] The above technical solution has the following advantages or beneficial effects:

[0029] The self-expanding vascular stent for special use in cerebrovascular occlusion lesions provided by the present invention has the effect of reducing or avoiding mutual extrusion of two self-expanding sections by setting a preset distance between two adjacent self-expanding sections. When the self-expanding vascular stent for special use in cerebrovascular occlusion lesions of the present invention is actually applied to a blood vessel with a bent portion, the amount of deformation generated by the self-expanding vascular stent for special use in cerebrovascular occlusion lesions located at the bent portion is smaller than the amount of deformation generated by the vascular stent of the prior art located at the bent portion, and at least solves the technical problem in the prior art of how to reduce the deformation of the inner arc portion of the vascular stent of the prior art towards the inside of the vascular stent at its bent portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of the first self-expanding vascular stent for special use in cerebrovascular occlusion lesions with a coating layer provided by Embodiment 1 of the present invention;

[0031] Figure 2 It is a schematic structural diagram of the self-expanding section provided by Embodiment 1 of the present invention;

[0032] Figure 3 It is a schematic structural diagram of the self-expanding section provided by Embodiment 1 of the present invention;

[0033] Figure 4 It is an axial schematic structural diagram of a part of the self-expanding section provided by Embodiment 1 of the present invention;

[0034] Figure 5 Schematic diagram of the structure of the second self-expanding vascular stent for cerebrovascular occlusion lesions with a film coating layer provided in Embodiment 1 of the present invention;

[0035] Figure 6 Schematic diagram of the structure of the third self-expanding vascular stent for cerebrovascular occlusion lesions with a film coating layer provided in Embodiment 1 of the present invention;

[0036] Figure 7 Schematic diagram of the structure of the fourth self-expanding vascular stent for cerebrovascular occlusion lesions without a film coating layer provided in Embodiment 1 of the present invention;

[0037] Figure 8 Schematic diagram of the structure of the fifth self-expanding vascular stent for cerebrovascular occlusion lesions without a film coating layer provided in Embodiment 1 of the present invention;

[0038] Figure 9 Schematic diagram of the first bending structure of the self-expanding vascular stent for cerebrovascular occlusion lesions without a film coating layer provided in Embodiment 1 of the present invention;

[0039] Figure 10 Schematic diagram of the second bending structure of the self-expanding vascular stent for cerebrovascular occlusion lesions with a film coating layer provided in Embodiment 1 of the present invention;

[0040] Figure 11 Schematic diagram of the structure of the sixth self-expanding vascular stent for cerebrovascular occlusion lesions with a film coating layer provided in Embodiment 1 of the present invention;

[0041] Figure 12 Schematic diagram of the third bending structure of the self-expanding vascular stent for cerebrovascular occlusion lesions without a film coating layer provided in Embodiment 1 of the present invention;

[0042] Figure 13 Schematic diagram of the fourth bending structure of the self-expanding vascular stent for cerebrovascular occlusion lesions with a film coating layer provided in Embodiment 1 of the present invention;

[0043] Figure 14 Schematic diagram of the vascular structure of the intracranial segment of the carotid artery. Detailed implementation manner

[0044] Embodiment 1:

[0045] In this embodiment, a self-expanding vascular stent for cerebrovascular occlusion lesions is provided. Refer to Figures 1 to 13 , which includes a plurality of self-expanding segments 1;

[0046] Any one of the self-expanding segments 1 is respectively arranged in a ring shape, and the inner cavities of two adjacent self-expanding segments 1 are communicated with each other;

[0047] Axial ends of any self-expanding section 1 are respectively a head end and a tail end. A preset spacing 2 is provided between the tail end of one self-expanding section 1 and the head end of another adjacent self-expanding section 1.

[0048] An adjacent pair of self-expanding sections 1 are connected by a connecting component 3 to form a movable and inseparable connection structure.

[0049] The self-expanding section 1 is made of a shape memory alloy material. After undergoing plastic deformation within a certain temperature range, the shape memory alloy material can restore its original macroscopic shape within another temperature range. Refer to Figure 2 or Figure 3 The self-expanding section 1 is integrally in a circular mesh structure and has a certain elasticity. When receiving an axial-to-center extrusion force, the self-expanding section 1 can deform along the axial direction towards the center. Or, when receiving a radial-to-center extrusion force, the self-expanding section 1 can deform along the radial direction towards the center.

[0050] The inner cavity of the self-expanding section 1 is used for blood circulation. Specifically, when the self-expanding section 1 is restricted within the shell tube, the self-expanding section 1 is in a compressed state as a whole, so that the inner cavity of the self-expanding section 1 cannot circulate blood. After the self-expanding section 1 is restricted within the blood vessel and separated from the shell tube, the self-expanding section 1 undergoes a first diastolic due to its own elastic force. At this time, the inner cavity of the self-expanding section 1 can circulate blood. Then, after the self-expanding section 1 reaches a preset temperature due to the body temperature of the patient, it undergoes a second diastolic and restores its original macroscopic shape.

[0051] Refer to Figure 2 、 Figures 5 to 8 、 Figures 10 to 13 A preset spacing 2 is provided between adjacent self-expanding sections 1. The function of this preset spacing 2 is: when the two self-expanding sections 1 approach each other, it provides a preset space to reduce or avoid mutual extrusion between the two self-expanding sections 1.

[0052] For example: the staff manually squeezes two self-expanding sections 1 axially towards each other. At this time, due to the existence of the preset spacing 2, the two self-expanding sections 1 first have a moving trend of approaching each other. Before the two self-expanding sections 1 actually come into contact, no force is exerted between them, thus avoiding mutual extrusion between the two self-expanding sections 1.

[0053] For example: the staff manually bends two self-expanding sections 1, causing a driving force for the two self-expanding sections 1 to approach each other at the inner arc part of the bending position. Before the two self-expanding sections 1 actually come into contact, no force is exerted between them, thus avoiding mutual extrusion between the two self-expanding sections 1.

[0054] For example, when a self-expanding vascular stent specifically for cerebrovascular occlusion lesions in this embodiment is actually disposed in a blood vessel with a relatively large curvature, due to the influence of the curved portion of the blood vessel, the two self-expanding segments 1 approach each other at the inner arc portion of the curved portion of the blood vessel. No force is applied between the two self-expanding segments 1, thus avoiding mutual extrusion of the two self-expanding segments 1.

[0055] For example: The staff manually bends the two self-expanding segments 1. Before the two self-expanding segments 1 actually come into contact with each other, no force is applied between the two self-expanding segments 1, thus avoiding mutual extrusion of the two self-expanding segments 1. After the two self-expanding segments 1 come into contact with each other at the inner arc portion of the bending portion, the two self-expanding segments 1 deform respectively at the inner arc portion. However, the contact portion of the two self-expanding segments 1 only receives a force along the axial direction of the self-expanding segment 1, and does not receive a force along the circumferential direction of the self-expanding segment 1, thereby reducing the phenomenon of mutual extrusion of the two self-expanding segments 1.

[0056] Between two adjacent self-expanding segments 1, a connecting component 3 is used for connection, so that the two self-expanding segments 1 form a mutually connected structure. At the same time, during the bending process of a self-expanding vascular stent specifically for cerebrovascular occlusion lesions in this embodiment, in order to avoid the connecting component 3 from applying a force along the axial direction of the self-expanding segment 1 to the two self-expanding segments 1, the connecting component 3 and the self-expanding segment 1 should be set as a movable connection structure, so that the two self-expanding segments 1 form a movable and inseparable connection structure through the connecting component 3.

[0057] In the prior art, a vascular stent for aneurysms at the bifurcation of cerebral arteries, the patent document with the application number 201520538028.0, does not have the self-expanding segment 1 structure of this embodiment. In other words, if the prior art is forcibly divided into multiple'self-expanding segments', then, a fixed connection method is adopted between the multiple self-expanding segments in the prior art, that is, it does not have the connecting component 3 in this embodiment.

[0058] In the prior art, a self-expanding drug-coated vascular stent, the patent document with the application number 202121238234.1, has main struts (equivalent to the self-expanding segment 1 in this embodiment) and connecting struts (equivalent to the connecting component 3 in this embodiment). However, the main struts and the connecting struts in the prior art are fixedly connected, rather than the movable connection structure between the self-expanding segment 1 and the connecting component 3 in this embodiment. Furthermore, the connection structure formed by the connecting struts between two adjacent main struts in the prior art is not the movable and inseparable connection structure formed by two adjacent self-expanding segments 1 and the connecting component 3 in this embodiment.

[0059] For the convenience of understanding by those skilled in the art, in this embodiment, a preferred solution of 'a movable and inseparable connection structure formed by two adjacent self-expanding segments 1 and the connecting member 3' is provided, specifically as follows:

[0060] See Figure 1 、 Figures 5 to 13 , the connecting member 3 is specifically a connecting wire;

[0061] The connecting wire connects at least two of the self-expanding segments 1. The connecting wire is made of a metal material or a non-metal material. Among them, the two ends of the connecting wire are welded together.

[0062] Among them, the connecting wire can be a metal material applied in the human blood vessel, such as: stainless steel or nitinol alloy, or a non-metal material applied in the human blood vessel, such as: polymer material. Since the connecting wire is set in a filamentous shape, after the connecting wire forms a connection structure with two adjacent self-expanding segments 1 respectively, the two ends of the connecting wire need to be welded together to prevent the self-expanding segment 1 from separating from the connecting wire. Among them, the two ends of the connecting wire are welded by an ultrasonic welding process.

[0063] The connecting wire should have a preset toughness and flexibility. Among them, the toughness of the connecting wire should at least meet the requirement that it will not break during the actual release process of a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment, and the flexibility of the connecting wire should be higher than that of the self-expanding segment 1, at least the flexibility of the connecting wire is equivalent to that of the self-expanding segment 1. Thus, during the process of two adjacent self-expanding segments 1 approaching each other, the connecting wire deforms first, and before the two self-expanding segments 1 come into contact with each other, it is very rare for the two self-expanding segments 1 to be affected by the force of the connecting wire.

[0064] The circumferential parts of any one of the self-expanding segments 1 are respectively reticular circumferential parts. A plurality of mesh holes are provided in the reticular circumferential parts, and a deformable positioning ring 4 is provided at at least one mesh hole. The connecting wire is restricted between the reticular circumferential part and the positioning ring 4.

[0065] In this embodiment, the material of the positioning ring 4 is configured to be the same as the material of the self-expanding segment 1; the function of the positioning ring 4 is: to limit the axial movement range or circumferential movement range of the connecting wire relative to the self-expanding segment 1. Since the connecting wire is actually restricted between the positioning ring 4 and the reticular circumferential part, the connecting wire and the self-expanding segment 1 form a movable connection structure, and after the two ends of the connecting wire are welded together, two adjacent self-expanding segments 1 form a movable and inseparable connection structure through the connecting wire.

[0066] It should be understood that, in addition to the aforementioned connecting wires, the connecting member 3 can also adopt other forms of connecting members 3, for example: a connecting member 3 in the form of an 8-shaped rotating ring structure, or two connecting members 3 in the form of paper clip structures; however, the processing technology of the connecting wire is of low difficulty, and relatively, the processing technology of the connecting member 3 in the form of an 8-shaped rotating ring structure is of high difficulty; at the same time, the assembly process of the connecting wire is relatively simple, and only the two ends of the connecting wire need to be welded, while the assembly process of using two connecting members 3 in the form of paper clip structures is relatively difficult, and it is necessary to use auxiliary magnifying equipment and cooperate with corresponding tools such as pliers to connect the two paper clip-shaped structures together; moreover, the connecting member 3 in the form of an 8-shaped rotating ring structure, or two connecting members 3 in the form of paper clip structures, occupy more space than the space occupied by the connecting wire, and can only be applied to blood vessels with a relatively large diameter, and cannot be applied to blood vessels with a relatively small diameter, that is, the actual use modes of these two connecting members 3 are restricted by the blood vessel diameter. Therefore, from the overall economic cost and actual application environment of a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment, the connecting wire is the preferred solution with the lowest economic cost provided by the inventor at present.

[0067] Further, in some surgeries, a vascular stent with a membrane needs to be used; in the aforementioned solution, since the connecting wire is restricted between the reticular circumferential part and the positioning ring 4, if the positioning ring 4 and the reticular circumferential part are on the same inner surface and outer surface, then the connecting wire will inevitably produce a protruding part towards the inner cavity direction of the self-expanding section 1, and thus this protruding part will affect the connection between the membrane and the self-expanding section 1.

[0068] To solve this problem, in a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment, the positioning ring 4 has a squeezed state and a natural state. When the positioning ring 4 is in the natural state, along the radial direction of the self-expanding section 1, a connection gap 5 is formed between the curved surface where the positioning ring 4 is located and the outer surface of the reticular circumferential part (see Figure 3 or Figure 4 ), and the connection gap 5 is used for the connecting wire to penetrate.

[0069] Specifically, the material used for the positioning ring 4 should be the same as the material of the self-expanding section 1. Preferably, the positioning ring 4 and the self-expanding section 1 are integrally processed. This setting method makes the positioning ring 4 also in a contracted state (i.e., the squeezed state) when the self-expanding section 1 is in a contracted state, and conversely, when the self-expanding section 1 is in an expanded state, the positioning ring 4 is also in an expanded state (i.e., the natural state), so that at the same moment, the state of the self-expanding section 1 and the state of the positioning ring 4 are in the same state.

[0070] The positioning ring 4 actually protrudes radially from the self-expanding section 1 beyond the outer circumferential surface of the reticular circumferential part, which forms a gap for the connecting wire to pass through between the inner surface of the positioning ring 4 and the outer surface of the reticular circumferential part. The self-expanding section 1 and the connecting wire can form a movable connection along the axial or circumferential direction through this gap. When a film is provided, the film should be provided on the inner surface of the reticular circumferential part of any self-expanding section 1, so that the film, the connecting wire, and the inner surface of the self-expanding section 1 are blocked by the reticular circumferential part, preventing the connecting wire from affecting the connection structure between the film and the self-expanding section 1.

[0071] Furthermore, a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment can be actually designed into multiple schemes based on the connecting wire and the positioning ring 4. The following lists multiple schemes:

[0072] Scheme 1: Refer to Figure 1 , the number of connecting wires is multiple, and among them, there is and only one connecting wire between two adjacent self-expanding sections 1;

[0073] Any self-expanding section 1 is respectively provided with at least two connecting gaps 5, and all the connecting gaps 5 between two adjacent self-expanding sections 1 are penetrated by the same connecting wire.

[0074] Scheme 2: Refer to Figure 5 , the number of connecting wires is multiple, and among them, there are at least two connecting wires between two adjacent self-expanding sections 1;

[0075] Any self-expanding section 1 is respectively provided with at least two connecting gaps 5, and any connecting wire penetrates one of the connecting gaps 5 between two adjacent self-expanding sections 1.

[0076] In the above Scheme 1 and Scheme 2, due to the relatively large number of connecting wires, the welding work of the connecting wires is large, resulting in a relatively high manufacturing cost.

[0077] Scheme 3: Refer to Figure 6 or Figure 7 , the number of connecting wires is set to be one and only one;

[0078] Any self-expanding section 1 is respectively provided with at least two connecting gaps 5, and all the connecting gaps 5 of all the self-expanding sections 1 are penetrated by the connecting wire.

[0079] Scheme 4: Refer to Figure 8 or Figure 9 , the number of connecting wires is set to be at least two;

[0080] Any self-expanding section 1 is respectively provided with at least four connecting gaps 5, and two of the connecting gaps 5 of any self-expanding section 1 are penetrated by one of the connecting wires.

[0081] In the above-mentioned Solution 3 and Solution 4, since the number of connecting wires is relatively small, the soldering work of the connecting wires is less, resulting in a relatively low manufacturing cost.

[0082] Furthermore, for a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment, in order to reduce or avoid the bending phenomenon generated when the connecting wire penetrates the preset gap, the following preferred solution is proposed:

[0083] See Figure 3 , along the axial direction of the self-expanding section 1, the positioning ring 4 and the self-expanding section 1 form two axial connection points 501;

[0084] Or, see Figure 2 , along the circumferential direction of the self-expanding section 1, the positioning ring 4 and the self-expanding section 1 form two circumferential connection points 502.

[0085] Among them, when the positioning ring 4 and the self-expanding section 1 form two axial connection points 501, the positioning ring 4 is actually arranged along the axial direction of the self-expanding section 1. In order to reduce or avoid bending when the connecting wire penetrates the preset gap, the connecting wire should penetrate the preset gap between the positioning ring 4 and the mesh circumferential part along the circumferential direction of the self-expanding section 1; this setting method of the positioning ring 4 is applicable to the aforementioned Solution 1 and Solution 2.

[0086] And, when the positioning ring 4 and the self-expanding section 1 form two circumferential connection points 502, the positioning ring 4 is actually arranged along the circumferential direction of the self-expanding section 1. In order to reduce or avoid bending when the connecting wire penetrates the preset gap, the connecting wire should penetrate the preset gap between the positioning ring 4 and the mesh circumferential part along the axial direction of the self-expanding section 1; this setting method of the positioning ring 4 is applicable to the aforementioned Solution 3 and Solution 4.

[0087] Furthermore, for a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment, the self-expanding section 1 is made of memory metal wires by a weaving process, where the positioning ring 4 is a part of the memory metal wires; or, the self-expanding section 1 is made of a memory metal tube by a laser cutting process, where the positioning ring 4 is a part of the memory metal tube.

[0088] During the weaving process using memory metal wires, a specially set weaving stent (not shown in the figure) is required. This weaving stent has, in addition to the first structure for weaving the mesh circumferential part, a second structure for weaving the positioning ring 4 of this embodiment; the second structure should at least include six rod-shaped parts and a padding base. Among them, the six rod-shaped parts are arranged at the vertices of a regular hexagon on the same padding base, and one memory metal wire is wound around the six rod-shaped parts in a twisted manner to form the positioning ring 4. Since the padding base protrudes from the first structure, the positioning ring 4 will actually be higher than the mesh circumferential part after being woven.

[0089] During the cutting process using the laser cutting process, a special memory metal tube needs to be used. In addition to having a tubular structure, the special memory metal tube also has protrusions on the surface of the tubular structure (not shown in the figure). During actual cutting, the surface of the remaining tubular structure except for the protrusions is used to be cut into a reticulated circumferential part, and the protrusions are used to be cut into the positioning ring 4. Since the protrusions protrude from the surface of the reticulated structure, the positioning ring 4 will actually be higher than the reticulated circumferential part after being cut.

[0090] In addition to the foregoing, a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment is shown in Figure 1 、 Figure 5 、 Figure 6 、 Figure 10 、 Figure 11 or Figure 13 ,and further includes a membrane layer 6;

[0091] The self-expanding section 1 has an inner surface and an outer surface. The membrane layer 6 is arranged in a sleeve shape. The membrane layer 6 is located in the inner cavities of a plurality of self-expanding sections 1, and the membrane layer 6 is closely attached to the inner surfaces of the plurality of self-expanding sections 1.

[0092] Among them, the membrane layer 6 has the function of isolating the blood vessel wall from the blood. In addition, a drug coating can be provided on the membrane layer 6, and the drug coating is used to absorb and release dissolved drugs.

[0093] In addition to the foregoing, a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment further includes a shell tube (not shown in the figure);

[0094] The self-expanding section 1 has an expanded state and a contracted state. When the self-expanding section 1 is located inside the shell tube, the self-expanding section 1 is in the contracted state. When the self-expanding section 1 is located outside the shell tube, the self-expanding section 1 changes from the contracted state to the expanded state.

[0095] A self-expanding vascular stent dedicated to cerebrovascular occlusion lesions provided in this embodiment, during the actual manufacturing process, first, the number of self-expanding segments 1 is manufactured into multiple by using the braiding process of shape memory wire or the laser cutting process of shape memory tube. Among them, a positioning ring 4 is respectively braided or cut out on any one of the self-expanding segments 1, and a preset gap is formed between the positioning ring 4 and the reticular circumferential part; connecting wires respectively penetrate the preset gaps of two adjacent self-expanding segments 1, and after penetration is completed in any one of the foregoing solutions 1 to 4, both ends of each connecting wire are welded by ultrasonic welding process, and the redundant connecting wires are cut off; before welding the connecting wires, the self-expanding segments 1 can be compressed by using a compression tool, so that the length of the connecting wires exposed on the outer surface of the self-expanding segments 1 is longer, which is convenient for setting both ends of the connecting wires on the ultrasonic welding equipment for welding, and avoiding the too long connecting wires staying on the self-expanding segments 1; when there is a requirement for film coating, the film coating is arranged in the inner cavities of multiple self-expanding segments 1, so that the film coating adheres to the inner surface of the reticular circumferential part of any one of the self-expanding segments 1; after both ends of all the connecting wires are welded respectively, the first composition of the self-expanding segments 1 and the connecting wires can be arranged in the shell tube by using the method of the prior art, or the second composition of the self-expanding segments 1, the connecting wires and the film coating can be arranged in the shell tube by using the method of the prior art.

[0096] A self-expanding vascular stent dedicated to cerebrovascular occlusion lesions provided in this embodiment, during the actual application process, the releasing method of any one of the self-expanding segments 1 relative to the shell tube is the same as that of the self-expanding stent relative to the shell tube in the prior art, which will not be elaborated here; the difference is that there is a time difference between the self-expanding segment 1 released first and the self-expanding segment 1 released later. During this time difference, the self-expanding segment 1 released first and the self-expanding segment 1 released later can form a relatively bent state, so that the two self-expanding segments 1 actually squeeze the preset distance 2, rather than directly squeezing each other; among them, since a movable and inseparable connection structure is formed between the self-expanding segment 1 in the front and the self-expanding segment 1 in the back through the connecting wire, the connecting wire actually follows each self-expanding segment 1 to be released; during the process of the two self-expanding segments 1 forming a relatively bent state, the connecting wire located at or near the inner arc part of the bending part forms a bend on the circumferential outer surface of the self-expanding segment 1.

[0097] A self-expanding vascular stent dedicated to cerebrovascular occlusion lesions provided in this embodiment, when actually applied in blood vessels with many curved parts, such as the intracranial segment of the carotid artery. Since the adjacent two self-expanding segments 1 can be bent arbitrarily, or it can be approximately regarded as universal bending between the adjacent two self-expanding segments 1, the length of the self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment can be configured to be long enough, for example, one of 10 cm to 20 cm, and it can adapt to blood vessels with different bending directions. Therefore, the application range of the self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment is wider. In addition, for the self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment, during the operation, a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions with a corresponding length can be matched according to the actual blood vessel length of the patient. Furthermore, during the operation, a one-time release method can be adopted, which reduces the operation time and improves the efficiency compared with the method of releasing the existing vascular stents one by one more than two.

[0098] In the prior art (a vascular stent for aneurysms at the bifurcation of cerebral arteries, patent document with application number 201520538028.0), when the vascular stent is actually arranged in a blood vessel with a curved part, since it does not have the 'preset spacing 2 between the adjacent two self-expanding segments 1' in this embodiment, at the inner arc part of the curved part, the vascular stent can generate an axial force from its axial two ends to the inner arc part. This axial force causes the vascular stent at the inner arc part to bend outward to the outer arc part, and makes the adjacent vascular stent at the inner arc part deform and form a deformation trend from the inner arc part to the axial two ends; at the same time, the vascular stent generates a circumferential force along the circumferential direction from the outer arc part to the inner arc part. This circumferential force is generated during the axial deformation of the vascular stent between the inner arc part and the outer arc part. The direction of this circumferential force is opposite to the direction of the aforementioned 'deformation trend from the inner arc part to the axial two ends', causing the vascular stent to further generate a deformation trend along the radial direction at the inner arc part, so that after the vascular stent at the inner arc part is actually bent, a phenomenon similar to 'the collapsed bend of a steel pipe folded in half' is formed.

[0099] In the prior art (a self-expanding drug-coated vascular stent, patent document with application number 202121238234.1), when the vascular stent is actually arranged in a blood vessel with a curved part, although there is a certain gap between the adjacent two main bars, the adjacent two main bars are fixedly connected by connecting bars, which makes the vascular stent also generate an axial force from its axial two ends to the inner arc part at the curved part of the blood vessel. This axial force causes the vascular stent at the inner arc part to bend outward to the outer arc part, thus not achieving the effect of'reducing or avoiding the mutual extrusion between the two self-expanding segments 1 due to the preset spacing 2 between the adjacent two self-expanding segments 1' in this embodiment.

[0100] A self-expanding vascular stent dedicated to cerebrovascular occlusion lesions provided in this embodiment has a preset spacing 2 provided between two adjacent self-expanding segments 1, resulting in the effect of reducing or avoiding mutual extrusion between the two self-expanding segments 1; when a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions in this embodiment is actually applied to a blood vessel with a curved portion, the amount of deformation generated by the self-expanding vascular stent dedicated to cerebrovascular occlusion lesions located at the curved portion is less than the amount of deformation generated by the prior art vascular stent located at the curved portion, at least solving the technical problem in the prior art of how to reduce the deformation of the prior art vascular stent towards the inside of the vascular stent at the inner arc portion of its bending.

[0101] In addition, if a self-expanding vascular stent dedicated to cerebrovascular occlusion lesions provided in this embodiment is actually disposed in a blood vessel with a curved portion, but the curvature of the curved portion of the blood vessel is relatively small, due to the preset spacing 2 between two adjacent self-expanding segments 1, it can enable only bending but no contact between two adjacent self-expanding segments 1, thereby avoiding mutual extrusion between the two self-expanding segments 1 and solving the technical problem of how to avoid the deformation of the prior art vascular stent towards the inside of the vascular stent at the inner arc portion of its bending.

[0102] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made by using the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A self-expanding vascular stent dedicated to cerebrovascular occlusion lesions, characterized in that, It includes multiple self-expanding segments; Any one of the self-expanding segments is respectively arranged in a ring shape, and the inner cavities of two adjacent self-expanding segments communicate with each other; The axial two ends of any one of the self-expanding segments are respectively a head end and a tail end. Among two adjacent self-expanding segments, a preset distance is left between the tail end of one self-expanding segment and the head end of the other self-expanding segment; A movable and inseparable connection structure is formed between two adjacent self-expanding segments through a connecting component; The connecting component is specifically a connecting wire; The connecting wire connects at least two of the self-expanding segments. The connecting wire is made of a metal material or a non-metal material. Among them, the two ends of the connecting wire are welded together; The circumferential part of any one of the self-expanding segments is respectively a mesh circumferential part. A plurality of mesh holes are arranged in the mesh circumferential part. At least one of the mesh holes is provided with a deformable positioning ring, and the connecting wire is restricted between the mesh circumferential part and the positioning ring.

2. The self-expanding vascular stent for cerebrovascular occlusion lesions according to claim 1, wherein The positioning ring has a squeezed state and a natural state. When the positioning ring is in the natural state, a connecting gap is formed between the curved surface where the positioning ring is located and the outer surface of the mesh circumferential part along the radial direction of the self-expanding segment, and the connecting gap is used for the connecting wire to penetrate through.

3. The self-expanding vascular stent dedicated to cerebrovascular occlusion lesions according to claim 2, characterized in that, The number of the connecting wires is multiple. Among them, there is and only one connecting wire between two adjacent self-expanding segments; Any one of the self-expanding segments is respectively provided with at least two of the connecting gaps, and all the connecting gaps between two adjacent self-expanding segments are respectively penetrated by the same connecting wire.

4. The self-expanding vascular stent dedicated to cerebrovascular occlusion lesions according to claim 2, wherein The number of the connecting wires is set to be and only one; Any one of the self-expanding segments is respectively provided with at least two of the connecting gaps, and all the connecting gaps of all the self-expanding segments are penetrated by the connecting wire.

5. The self-expanding vascular stent dedicated to cerebrovascular occlusion lesions according to claim 1, characterized in that, Along the axial direction of the self-expanding segment, the positioning ring and the self-expanding segment form two axial connection points; Or, along the circumferential direction of the self-expanding segment, the positioning ring and the self-expanding segment form two circumferential connection points.

6. The self-expanding vascular stent dedicated to cerebrovascular occlusion lesions according to claim 1, wherein, The self-expanding segment is made of memory metal wires by a weaving process. Among them, the positioning ring is a part of the memory metal wires; Or, the self-expanding segment is made of a memory metal tube by a laser cutting process. Among them, the positioning ring is a part of the memory metal tube.

7. The self-expanding vascular stent dedicated to cerebrovascular occlusion lesions according to claim 1, wherein It further includes a film layer; The self-expanding segment has an inner surface and an outer surface. The film layer is arranged in a sleeve shape. The film layer is located in the inner cavities of multiple self-expanding segments, and the film layer is closely attached to the inner surfaces of multiple self-expanding segments.

8. The self-expanding vascular stent dedicated to cerebrovascular occlusion lesions according to claim 1, wherein It further includes a shell tube; The self-expanding segment has an expanded state and a contracted state. When the self-expanding segment is located inside the shell tube, the self-expanding segment is in the contracted state. When the self-expanding segment is located outside the shell tube, the self-expanding segment changes from the contracted state to the expanded state.

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