Intracranial vascular implantation device

Abstract

The invention relates to an intracranial blood vessel implanting device which comprises a net pipe support, the net pipe support comprises a plurality of grid holes, the net pipe support further comprises a far-end part, a middle part and a near-end part which are sequentially connected from the far end to the near end in the axial direction of the net pipe support, and the grid holes in the near-end part are smaller than the grid holes in the middle part; blood flow can pass through the grid holes in the middle part, and the far-end part is in a horn mouth shape which is opened outwards; and the covering film is arranged on at least part of the inner surface of the far-end part. According to the device, immediate plugging of aneurysms can be achieved while smoothness of bifurcated blood vessels is guaranteed, meanwhile, the good radial supporting performance is achieved, and the whole device is effectively prevented from moving.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an intracranial blood vessel implantation device for intracranial bifurcation aneurysms. Background Art

[0002] Intracranial aneurysms are usually abnormal bulges of the intracranial arterial wall, which often occur at the bifurcation site. They are the main cause of subarachnoid hemorrhage, and their incidence rate is second only to cerebral thrombosis and hypertensive cerebral hemorrhage. With the development of interventional technology and the improvement of equipment, endovascular treatment of intracranial aneurysms has become more and more widespread. However, due to the complex vascular structure of intracranial bifurcation aneurysms, their treatment remains challenging, especially for bifurcation wide-necked aneurysms (accounting for about 26-36% of all intracranial aneurysms).

[0003] The existing intravascular implantation devices used to treat intracranial bifurcation aneurysms, such as simple coil embolization or stent-assisted embolization, are not sufficient to prevent coil dislocation, and the packing density is usually not high, with a high risk of recurrence; while the blood flow guidance device has a high metal coverage rate, but it will affect the blood flow of the branch vessels, easily causing branch artery occlusion and local ischemia. At present, clinical use of Y-type, X-type and other stent implantation techniques to release double stents to assist coil embolization in order to achieve a good support effect and ultimately achieve aneurysm treatment, but this undoubtedly increases the difficulty of surgical operation, increases the amount of metal implanted in the stent, and increases perioperative risks such as thrombosis and stenosis.

[0004] Therefore, for technicians in this field, how to design an intracranial vascular implant device suitable for treating intracranial bifurcation aneurysms, especially wide-necked bifurcation aneurysms, so that the operation of the device becomes simpler and more effective and has certain clinical significance is a problem that needs to be solved urgently. Summary of the invention

[0005] Based on this, the purpose of the present invention is to provide an intracranial vascular implant device, which aims to overcome the risks of spring coils being easily dislodged and having a high recurrence rate in the case of intracranial bifurcation aneurysms, as well as the limitations of blood flow guidance devices causing branch vessel occlusion.

[0006] To achieve the above object, an intracranial vascular implantation device comprises:

[0007] A mesh management bracket, the mesh management bracket includes a plurality of mesh holes, the mesh management bracket also includes a distal portion, a middle portion and a proximal portion which are sequentially connected along the axis of the mesh management bracket from the distal end to the proximal end, the mesh holes of the proximal portion are smaller than the mesh holes of the middle portion, the mesh holes of the middle portion can pass blood flow, the distal portion is divided into a trumpet shape that opens outward; and a coating, the coating is arranged on at least a portion of the inner surface of the distal portion.

[0008] Optionally, the coating is provided with a drug that promotes endothelialization of the tumor neck.

[0009] Optionally, the drug is a growth factor that promotes endothelialization of the tumor neck, and the drug is a drug solution containing the growth factor coated on the film, and the concentration of the growth factor is 1 μg / mL to 100 μg / mL.

[0010] Optionally, the drug is coated on the film by at least one of dipping, spraying and deposition of the drug solution.

[0011] Optionally, the plurality of grid holes include first diamond grid holes, second diamond grid holes and third diamond grid holes, the distal portion includes the first diamond grid holes and the second diamond grid holes, and / or the middle portion includes the first diamond grid holes and the second diamond grid holes, the first diamond grid holes and the second diamond grid holes have different aspect ratios, and the proximal portion includes the third diamond grid holes, and the third diamond grid holes have a preset aspect ratio.

[0012] Optionally, the aspect ratio of the first diamond-shaped mesh holes is 0.1-0.5, the aspect ratio of the second diamond-shaped mesh holes is 1.5-2.0, and the aspect ratio of the third diamond-shaped mesh holes is 0.5-1.5.

[0013] Optionally, the ratio of the length of the distal portion, the length of the middle portion and the length of the proximal portion is (0.1-1):1:(1-2), and the length of the middle portion is 1.0 mm to 10 mm.

[0014] Optionally, the angle between the flare of the distal portion and the longitudinal axis of the network management support is 45° to 60°.

[0015] Optionally, the proximal end of the proximal part is configured as a trumpet-shaped mouth that opens outward, and an angle between the trumpet-shaped mouth of the proximal part and the longitudinal axis of the network management support does not exceed 45°.

[0016] Optionally, the angle of the bell mouth of the proximal portion is 30° to 45°.

[0017] Optionally, the proximal end of the proximal part is set to a trumpet mouth that flares outward, the diameter of the trumpet mouth of the distal part is 4mm to 15mm, the diameter of the middle part and the diameter of the part of the proximal part except the proximal trumpet mouth are both 1mm to 5mm, and the diameter of the trumpet mouth of the proximal part is 4mm to 8mm.

[0018] Optionally, the mesh hole density of the middle part is 0.01 to 0.5 holes / mm2 The mesh hole density of the proximal part is 0.5 to 5 holes / mm 2 .

[0019] Optionally, the distal end portion is unfolded into a petal-shaped trumpet mouth, and 2 to 8 diamond-shaped grid holes are provided along the circumference.

[0020] Optionally, the network management bracket is formed by integrally cutting from a metal pipe.

[0021] Optionally, the network management bracket further satisfies at least one of the following conditions:

[0022] The distal end of the distal portion is provided with at least one developing point;

[0023] The proximal end of the proximal portion is provided with at least one developing point;

[0024] At least one developing point is provided at the junction of the distal portion and the middle portion;

[0025] At least one developing point is arranged at the junction of the middle portion and the proximal portion.

[0026] Optionally, the diameter of the inscribed circle of the mesh holes of the middle portion for positioning in the bifurcated blood vessel is greater than or equal to the average diameter of the bifurcated blood vessel.

[0027] Optionally, the network management bracket as a whole adopts grid holes of the same shape, and the multiple grid holes distributed along the circumference of the network management bracket in the middle part are all connected by bracket rods.

[0028] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects:

[0029] After the entire intracranial vascular implant device is implanted in the body, the trumpet-shaped distal part can fit the aneurysm wall, stably position in the intracranial bifurcated aneurysm, and cross the aneurysm neck, so that the coating on the distal part covers the aneurysm neck and achieves an immediate occlusion effect. At the same time, the middle part has larger mesh holes, which will not hinder the blood flow in the bifurcated blood vessels, ensuring the smooth flow of blood. In addition, the proximal part has smaller mesh holes and a high material coverage rate, which can provide sufficient radial support and prevent the entire device from shifting, ensuring the long-term stability of the entire device in the body. In addition, the surgical operation of the entire device can be simpler and the occlusion effectiveness is better. Furthermore, a growth factor that promotes endothelialization of the aneurysm neck is set on the coating. While accelerating the endothelialization of the aneurysm neck and improving blood flow, it can improve the healing rate of intracranial bifurcated aneurysms, and it is also expected to avoid the implantation of coils, which not only reduces the risk of internal leakage, has a good occlusion effect, but also reduces the risk of bleeding and the probability of recurrence. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Those skilled in the art will appreciate that the drawings are provided for a better understanding of the present invention, but do not constitute any limitation on the scope of the present invention.

[0031] Figure 1 A schematic diagram of the structure of a network management support of an intracranial vascular implantation device according to an embodiment of the present invention;

[0032] Figure 2 This is a main view of the scene of the intracranial vascular implantation device of an embodiment of the present invention treating an intracranial bifurcation aneurysm;

[0033] Figure 3 This is a side view of the scene of the intracranial vascular implantation device according to an embodiment of the present invention being used to treat an intracranial bifurcation aneurysm;

[0034] Figure 4 FIG. 4 is a schematic structural diagram of a mesh tube stent of an intracranial vascular implantation device according to another embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, advantages and features of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings. It should be noted that the accompanying drawings are in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In addition, the following embodiments and features in the embodiments can complement or be combined with each other without conflict.

[0036] Specifically, in this application document, the "proximal end" generally refers to the end close to the device operator; the "distal end" is opposite to the "proximal end" and refers to the end far from the device operator. In addition, the "axial direction" generally refers to the direction of the longitudinal axis; the "radial direction" refers to the direction perpendicular to the longitudinal axis, that is, the diameter direction; and the "circumferential direction" refers to the direction around the longitudinal axis.

[0037] The core idea of ​​the present invention is to provide an intracranial vascular implant device for the treatment of intracranial bifurcation aneurysms, particularly suitable for the treatment of wide-necked aneurysms, aiming to solve at least one problem existing in existing intravascular implant devices in the treatment of intracranial bifurcation aneurysms.

[0038] The intracranial vascular implant device provided by the present invention has good support, can be stably fixed at the target position, ensures long-term stability, and has good flexibility, is easy to push, and can be applied to various intracranial bifurcation aneurysms, with a wide range of applications.

[0039] The following is a description with reference to the accompanying drawings.

[0040] Figure 1 The structure of the intracranial blood vessel implantation device 100 provided by the present invention is schematically shown. Figure 1As shown, the intracranial vascular implant device 100 includes a mesh stent 110. The mesh stent 110 has an expanded form and a compressed form that can be delivered in a catheter (such as a microcatheter). The mesh stent 110 includes a plurality of grid holes 110A, each of which is formed by at least four stent rods 110B connected end to end to form a polygonal grid hole 110A such as a rhombus. In this embodiment, the grid hole 110A is a rhombus, which has good stability and support, and has better pushing performance during transportation than an irregular quadrilateral.

[0041] The mesh support 110 also includes a distal portion 111, a middle portion 112 and a proximal portion 113 connected in sequence from the distal end to the proximal end along its own axial direction. The mesh holes 110A of the proximal portion 113 are smaller than the mesh holes 110A of the middle portion 112, and the mesh holes 110A of the middle portion 112 should be able to allow the bifurcated blood vessel B (see Figure 2 ) through. In addition, the distal portion 111 is in the shape of a trumpet opening outward, which is convenient for anchoring in the tumor. The mesh holes 110A of the proximal portion 113 are relatively small, with a high material coverage rate, which can provide sufficient radial support and prevent the entire intracranial vascular implant device 100 from shifting. The mesh holes 110A of the middle portion 112 are relatively large, aiming to ensure smooth blood flow in the bifurcated blood vessel B. Because the mesh holes 110A of the same shape are used as a whole for the net management stent 110 (such as all rhombus-shaped mesh holes 110A), only the size of the mesh holes 110A is different, the mesh holes 110A of the middle part 112 are larger in size, and the mesh holes 110A distributed along the circumference of the net management stent 110 of the middle part 112 are all connected by the support rod 110B, that is, the circumferential connection points of the middle part 112 are all connected by the support rod 110B, so that the net management stent 110 can achieve uniform and good compression and release, and the proximal part 113 can provide good mechanical transmission and support to the distal part 111 through the support rod 110B and the connection point of the middle part 112. Therefore, the middle part 112 also has sufficient support, which not only makes the force transmission of the entire intracranial vascular implant device 100 more uniform during transportation, but also provides better support to the distal part 111 after implantation.

[0042] It should also be understood that, since the proximal portion 113 adopts a relatively small structure of the mesh holes 110A, the force conduction effect is good when the intracranial vascular implant device 100 is delivered, the force conduction is more uniform, and the support for the distal portion 111 after implantation is good, which can well reduce the risk of displacement of the distal portion 111, so that the distal portion 111 can be stably fixed in the aneurysm and positioned at the neck of the aneurysm, and is not easy to herniate into the bifurcated vessel B. Since the proximal portion 113 is in the shape of a mesh tube, it can also ensure that blood flows through its inner cavity, ensuring smooth blood flow in the main blood vessel C. After the proximal portion 113 is deployed, it can basically fit well with the vascular wall of the main blood vessel C, and the proximal portion 113 has good support in the main blood vessel C, and is not easy to shift or collapse.

[0043] like Figures 1 to 3 As shown, the intracranial vascular implant device 100 also includes a coating 120 disposed on the distal portion 111. The coating 120 is disposed on the inner surface of the distal portion 111 near the longitudinal axis L of the intracranial vascular implant device 100. The coating 120 basically extends along the inner surface of the distal portion 111, but the coating 120 can cover the entire inner surface or part of the inner surface of the distal portion 111. In general, the coating 120 at least partially covers the neck opening A1 of the intracranial bifurcation aneurysm A, achieving the purpose of immediate occlusion of the neck. The coating 120 basically does not move relative to the distal portion 111, and it can prevent blood from flowing into the intracranial bifurcation aneurysm A or flowing out of the intracranial bifurcation aneurysm A. The presence of the coating 120 not only reduces the risk of internal leakage, has a good occlusion effect, but also can achieve an immediate occlusion effect, reducing the risk of bleeding and the probability of recurrence.

[0044] Continue to refer to Figure 2 and Figure 3 After implantation in the body, the intracranial vascular implant device 100 is positioned in the body in an expanded posture, wherein the trumpet-shaped distal portion 111 fits the aneurysm wall, is stably positioned in the intracranial bifurcation aneurysm A and crosses the aneurysm neck A1, the middle portion 112 can cross the main vessel C to be positioned in the bifurcated vessel B without obstructing the blood flow of the bifurcated vessel B, and the proximal portion 113 is basically positioned as a whole in the main vessel C to provide good support to prevent the entire device from shifting. Therefore, after the intracranial vascular implant device 100 is applied, the amount of metal implanted in the stent can be reduced, the perioperative risk can be reduced, and the support is good, which can ensure the effectiveness and stability of the occlusion, and the surgical operation can be simpler. In general, the intracranial vascular implant device 100 can overcome the risks of coil dislocation and high recurrence rate in simple coil embolization or stent-assisted embolization treatment, as well as the limitations of branch vessel occlusion caused by blood flow guidance devices.

[0045] The distal portion 111, the middle portion 112 and the proximal portion 113 can be integrally processed and connected to each other, or separate distal portions 111, middle portions 112 and proximal portions 113 can be provided and connected to each other at the distal and proximal ends. In some embodiments, the distal portion 111, the middle portion 112 and the proximal portion 113 are formed by integrally cutting a metal tube. In an alternative embodiment, the proximal portion 113 is woven, and the distal portion 111 and the middle portion 112 are integrally cut from a metal tube, and then the distal end of the proximal portion 113 and the proximal end of the middle portion 112 are welded or bonded to each other. In the illustrated embodiment, the mesh support 110 is formed by integrally cutting a metal tube and then further heat-setting, so as to simplify the preparation process, while ensuring support and taking into account flexibility. There can be a variety of cutting methods, and one of them can be selected for execution, preferably laser cutting.

[0046] The mesh stent 110 can be made of various medical metal materials, such as but not limited to nickel-titanium, cobalt-chromium alloy, stainless steel and other medical metal materials, especially nickel-titanium alloy showing superelasticity is preferably used to prepare the mesh stent 110. Thus, the mesh stent 110 can be self-expanded.

[0047] The coating 120 can be an integral film, but it should be understood that the coating 120 can also be formed by splicing multiple films. In some embodiments, the edge of the coating 120 is fixed at the non-distal end (i.e., edge) of the distal portion 111, such as fixed at a position between the two ends of the stent rod 110B of the distal portion 111 rather than the distal end of the stent rod 110B. In other embodiments, the edge of the coating 120 is fixed at the distal end of the distal portion 111, such as fixed on the distal end of the stent rod 110B of the distal portion 111. Further, the coating 120 can also wrap the distal end of the distal portion 111, such as wrapping the distal end of the stent rod 110B positioned at the distal portion 111, thereby reducing the impact of the distal end of the distal portion 111 on the aneurysm wall, and further reducing the risk of rupture of the intracranial bifurcation aneurysm A. In the illustrated embodiment, the coating 120 is aligned with the distal end edge of the distal portion 111.

[0048] The covering 120 is configured to be substantially compatible with the anatomical structure of the neck opening A1 of the intracranial bifurcation aneurysm A, which facilitates the covering 120 to cross over and cover the neck opening A1. Thus, when positioned in the intracranial bifurcation aneurysm A, the covering 120 generally has a curved shape that is concave toward the neck opening A1. Similarly, the distal portion 111 also needs to cross over the neck opening A1 for support and positioning.

[0049] The membrane 120 is made of a polymer material that is substantially impermeable to liquids such as blood or body fluids, or a polymer material that allows liquids to at least limitedly flow through the membrane 120. The membrane 120 can be made of many suitable polymer materials, such as expanded polytetrafluoroethylene (ePTFE), polyurethane (PU), nylon, etc., without limitation. The membrane 120 and the distal portion 111 can be connected by at least one of suturing and gluing.

[0050] Preferably, the film 120 is provided with a drug that promotes endothelialization of the aneurysm neck, and the type of drug here is not specifically limited, for example, drugs that can accelerate vascular endothelialization such as growth factor VEGF, anti-CD31 antibody, polypeptide (RGD, REDV, YIGSR), etc. Preferably, the drug loaded on the film 120 is a growth factor that promotes endothelialization of the aneurysm neck, so as to reduce the recurrence rate of the aneurysm neck.

[0051] Thus, on the basis of the coating 120, the in situ endothelialization of the neck of the tumor A1 is promoted by the drug set on the coating 120, and the adhesion, proliferation and migration of endothelial cells on the coating 120 and the mesh stent 110 are stimulated, so as to achieve the rapid recovery of the intracranial bifurcation aneurysm A. The setting of the coating 120 and the drug makes it possible for the intracranial vascular implantation device 100 of the present invention to avoid the implantation of the coil, thereby avoiding the compression of the surrounding blood vessels. Finally, the device itself can close the intracranial bifurcation aneurysm A, form an endothelial layer, reduce the risk of bleeding and defective complications, and thus achieve the purpose of curing the intracranial bifurcation aneurysm A, especially the wide-necked aneurysm. It is understandable that the increase of the drug can accelerate the endothelialization of the neck of the tumor A1, improve the healing rate of the intracranial bifurcation aneurysm while improving the blood flow, and also help to save the coil and reduce the difficulty of surgical operation. In practice, the drug solution containing growth factors can be coated on the coating 120 by cyclic dipping, spraying or deposition. It should also be noted that the thickness of the drug is at the submicron level, preferably 1nm to 1000nm, more preferably 100nm to 500nm, to avoid the drug being too thick and easy to fall off, and to prevent the drug being too thin and unable to achieve the desired therapeutic effect. Preferably, in the drug solution, the concentration of the growth factor is 1μg / mL to 100μg / mL, which can ensure that the drug thickness meets the requirements, reduce the risk of falling off, and at the same time ensure the effect of promoting tumor neck endothelialization.

[0052] Preferably, the density of the mesh holes 110A in the middle portion 112 is 0.01 holes / mm to 0.5 holes / mm. 2 Therefore, the blood flow in the bifurcated blood vessel B can be improved by adjusting the density of the mesh holes 110A in the middle portion 112, reducing the impact on the blood flow in the bifurcated blood vessel B and reducing the risk of blood coagulation. Preferably, the density of the mesh holes 110A in the proximal portion 113 is 0.5 holes / mm to 5.0 holes / mm. 2, support can be ensured by adjusting the density of the mesh holes 110A of the proximal part 113.

[0053] The present application does not impose any particular limitation on the size of the mesh holes 110A of the distal portion 111. The distal portion 111 can basically cross the aneurysm neck A1, adapt to the shape of the aneurysm cavity, and fit the aneurysm wall. The distal portion 111 should generally have good flexibility and support. In the illustrated embodiment, the size of the mesh holes 110A of the distal portion 111 is also larger than the size of the mesh holes 110A of the proximal portion 113, so that the distal portion 111 has relatively large mesh holes 110A, which can reduce the stimulation to the aneurysm wall while taking into account flexibility and support, and further reduce the risk of rupture of the intracranial bifurcation aneurysm A.

[0054] Preferably, the distal portion 111 may present a petal-shaped trumpet mouth after being unfolded, so as to adapt to wide-necked or giant aneurysms. However, it should be recognized that the distal portion 111 may present a trumpet mouth of other shapes after being unfolded, and the present application does not limit this. Preferably, the number of mesh holes 110A of the distal portion 111 is 2 to 8, that is, 2 to 8 mesh holes 110A are provided along the circumference of the mesh tube stent 110, and no more than 8 at most, so as to reduce the stimulation to the aneurysm wall (that is, the cyst wall). In practice, 2 or 4 mesh holes 110A may be selected to form the distal portion 111. The distal portion 111 mainly serves to provide a base and support for the coating 120.

[0055] It is worth noting that the connection position between the proximal portion 113 and the middle portion 112 should have enough connection points to ensure the support of the middle portion 112. Specifically, the middle portion 112 has sufficient support in the direction of the longitudinal axis L, and at the same time has sufficient support in the transverse direction perpendicular to the longitudinal axis L to ensure support for the distal portion 111. In this regard, preferably, the grid holes 110A of the middle portion 112 are staggered in the axial direction of the mesh tube support 110 to ensure its own support performance without hindering the blood flow of the bifurcated blood vessel B. Here, axial staggering can be understood as the upper and lower grid holes 110A in the axial direction being staggered and not aligned in the circumferential direction. In addition, the mesh tube support 110 is a closed-loop structure as a whole, and has good overall support.

[0056] Further, the plurality of mesh holes 110A constituting the network management support 110 include a first diamond mesh hole, a second diamond mesh hole, and a third diamond mesh hole. The distal portion 111 includes a first diamond mesh hole and a second diamond mesh hole, the first diamond mesh hole and the second diamond mesh hole have different aspect ratios, and the radial support is ensured by the first diamond mesh hole, and the axial flexibility is ensured by the second diamond mesh hole. The distal portion 111 is composed of mesh holes 110A of different sizes, so that the distal portion 111 can take into account flexibility and radial support. And / or, the middle portion 112 includes a first diamond mesh hole and a second diamond mesh hole, so that the middle portion 112 is composed of mesh holes 110A of different sizes, so that the middle portion 112 can take into account flexibility and radial support. In addition, the proximal portion 113 includes a third diamond mesh hole, and the third diamond mesh hole has a preset aspect ratio, and the preset aspect ratio can enable the proximal portion 113 to take into account radial support and flexibility. The sizes of the third diamond-shaped mesh holes of the proximal portion 113 are substantially the same.

[0057] Preferably, the aspect ratio of the first diamond grid hole is 0.1 to 0.5. Preferably, the aspect ratio of the second diamond grid hole is 1.5 to 2.0. Preferably, the aspect ratio of the third diamond grid hole is 0.5 to 1.5. Here, the length of the grid hole 110A is the length of the line connecting the two diagonals of the diamond in the axial direction of the network management support, and the width of the grid hole 110A is the length of the line connecting the two diagonals of the diamond in the circumferential direction of the network management support. Therefore, when other conditions (such as materials) of the network management support 110 remain unchanged, adjusting the aspect ratio of the diamond grid hole 110A can change the radial support force and axial flexibility. Further research found that when the aspect ratio of the diamond does not exceed 0.5, the radial support is good, and when the aspect ratio of the diamond is not less than 1.5, the axial flexibility is good. On this basis, the aspect ratios of the first diamond grid hole, the second diamond grid hole and the third diamond grid hole are optimized.

[0058] In order to better support and anchor, the length of the proximal portion 113 should be long enough. Preferably, the length ratio of the distal portion 111, the middle portion 112 and the proximal portion 113 is (0.1-1):1:(1-2), and more preferably, the length ratio of the distal portion 111, the middle portion 112 and the proximal portion 113 is (0.1-0.5):1:(1.5-2), such as 0.5:1:1.5, or 0.5:1:1.7, or 0.3:1:2.0, or 0.2:1:1.8. By setting the length ratio of the three, an unexpected effect is that, on the one hand, the distal portion 111 is placed in the intracranial bifurcation aneurysm A without damaging the intracranial bifurcation aneurysm A, and on the other hand, the proximal portion 113 has enough length to be placed in the main blood vessel C to achieve support and anchor, and at the same time, the length of the middle portion 112 can adapt to most intracranial blood vessels.

[0059] The length of the middle portion 112 can be set according to the diameter of the bifurcated blood vessel B. Since the diameter of most intracranial blood vessels is 0.5 mm to 4.5 mm, the length of the middle portion 112 can be 1 mm to 10 mm. The mesh holes 110A of the middle portion 112 should be large enough to allow the stent rods 110B of the middle portion 112 to fit the vessel wall of the bifurcated blood vessel B as closely as possible without blocking blood flow. In more detail, as shown in FIG. Figure 3 As shown, the diameter of the inscribed circle D of the grid hole 110A of the middle portion 112 positioned in the bifurcated vessel B is greater than or equal to the average diameter of the bifurcated vessel 2, which can avoid the stent rod 110B from being exposed in the direction of blood flow to the greatest extent.

[0060] Return to reference Figure 1 In this embodiment, the distal portion 111 is a bell mouth after being unfolded, and the diameter (outer diameter) of the distal portion 111 is greater than the diameter (outer diameter) of the distal connection between the distal portion 111 and the middle portion 112, and the diameter (outer diameter) of the middle portion 112 is substantially the same as the diameter (outer diameter) of the proximal portion 113. The diameter at the distal edge of the distal portion 111 is the maximum diameter of the distal portion 111, and the diameter at the connection between the distal portion 111 and the middle portion 112 is the minimum diameter of the distal portion 111. The opening angle of the bell mouth of the distal portion 111 is set according to the size of the aneurysm neck A1. Preferably, the angle between the bell mouth of the distal portion 111 and the longitudinal axis L of the mesh stent 110 is 45° to 60°, such as 45°, 50° or 60°, etc. This angle enables the distal portion 111 to better fit the aneurysm wall and is suitable for most wide-necked aneurysms. The angle of the bell mouth of the distal portion 111 refers to the angle formed by the extension direction of the support rod 110B of the grid hole 110A of the distal portion 111 and the longitudinal axis L from the proximal end to the distal end.

[0061] In some embodiments, Figure 1 As shown, the distal portion 111 is composed of two rhombus-shaped mesh holes 110A, and the two mesh holes 110A are arranged opposite to each other in the circumferential direction. The length-to-width ratios of the two mesh holes 110A are the same, but may also be different. Figure 4 As shown, the distal portion 111 is composed of four mesh holes 110A, and the four mesh holes 110A are arranged sequentially in the circumferential direction. Preferably, the length-to-width ratios of the four mesh holes 110A are different to better balance flexibility and support. Figure 4 As shown, the aspect ratio of two grid holes 110A (i.e., the first diamond grid holes) is 0.1-0.5, and the aspect ratio of the other two grid holes 110A (i.e., the second diamond grid holes) is 1.5-2.0. The aspect ratios of adjacent grid holes 110A are different, so that the grid holes 110A constituting the distal part 111 have different lengths and widths.

[0062] Return to reference Figure 1 In some embodiments, the proximal portion 113 is a mesh tube with the same diameter as a whole, and both the proximal and distal ends thereof are straight ports. Figure 4 As shown, the proximal end of the proximal portion 113 is set to a trumpet mouth 113a that opens outward. The trumpet mouth 113a of the proximal portion 113 can enhance the anchoring performance of the proximal portion 113 in the main blood vessel C. Further, the angle between the trumpet mouth 113a of the proximal portion 113 and the longitudinal axis L of the mesh support 110 is no more than 45°, more preferably 30° to 45°, such as 30° or 45°, which is intended to reduce the stimulation to the blood vessel wall without damaging the blood vessel wall, while being able to anchor well in the blood vessel. The angle between the trumpet mouth 113a of the proximal portion 113 and the longitudinal axis L refers to the angle formed by the extension direction of the support rod 110B of the trumpet mouth 113a of the proximal portion 113 and the longitudinal axis L from the distal end to the proximal end.

[0063] In this embodiment, the mesh stent 110 includes three diameters. Specifically, the diameter of the bell mouth of the distal part 111 is a first diameter D1, and D1 can be selected to be 4mm to 15mm to adapt to different aneurysm sizes, especially wide-necked aneurysms; the diameter of the middle part 112 and the proximal part 113 except the bell mouth 113a is a second diameter D2, and D2 is 1mm to 5mm, such as 4.0mm, etc., to adapt to most intracranial blood vessels with a diameter of about 0.5mm to 4.5mm; in addition, the diameter of the bell mouth 113a of the proximal part 113 is a third diameter D3, and D3 is 4mm to 8mm, which is convenient for anchoring in the main blood vessel C.

[0064] The intracranial vascular implant device 100 of the present invention can be delivered into the body in a manner understood by those skilled in the art. For example, the intracranial vascular implant device 100 can be positioned on a delivery guide wire having a friction pad, and the delivery guide wire can be operated to move the intracranial vascular implant device 100 in the microcatheter, and finally released at the intracranial bifurcation aneurysm lesion site.

[0065] In some embodiments, at least one developing point is provided at the farthest end of the distal portion 111. In some embodiments, at least one developing point is provided at the closest end of the proximal portion 113. In some embodiments, at least one developing point is provided at the junction of the distal portion 111 and the middle portion 113. In some embodiments, at least one developing point is provided at the junction of the middle portion 112 and the proximal portion 113. The developing points at the corresponding positions are preferably distributed in at least three points in the circumferential direction to determine the open state and the wall-attached state of the stent.

[0066] Combine the following Figure 4 The intracranial vascular implantation device 100 of the present invention is further described in the following example.

[0067] like Figure 4 As shown, in a specific example, the diameter (D2) of the straight tube portion of the proximal portion 113 except the bell mouth 113a is 4mm, the length ratio of the distal portion 111, the middle portion 112 and the proximal portion 113 is 0.5:1:1.7, and the mesh support 110 is laser cut from a nickel-titanium alloy tube and further heat-set. In addition, the distal portion 111 is composed of four rhombus-shaped grid holes 110A arranged circumferentially to form a petal-shaped bell mouth, and the bell mouth angle is 60°. In addition, eight grid holes 110A are arranged on the same circumference of the proximal portion 113, and the aspect ratio of the grid holes 110A is 1.5. Furthermore, the angle of the bell mouth 113a of the proximal portion 113 is 30°. At the same time, the junction of the distal portion 111, the middle portion 112 and the proximal portion 113, as well as the farthest and nearest ends of the mesh support 110 are all provided with radiopaque development points. In addition, at the aneurysm neck A1 near the intracranial bifurcation aneurysm A, an ePTFE membrane (i.e., a covering membrane 120) is provided on the distal portion 111, and the ePTFE membrane is sewn and fixed to the distal tip of the stent rod 110B of the distal portion 111, so as to achieve immediate occlusion of the aneurysm through the ePTFE membrane. In addition, VEGF growth factor is carried on the ePTFE membrane to promote endothelialization of the aneurysm neck, reduce the risk of recurrence, and achieve the purpose of curing wide-necked aneurysms.

[0068] It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the method of the present invention, and these improvements and supplements should also be regarded as the protection scope of the present invention. Any technician familiar with this profession can make some changes, modifications and evolutions of the technical content disclosed above without departing from the spirit and scope of the present invention, which are equivalent embodiments of the present invention; at the same time, any changes, modifications and evolutions of any equivalent changes made to the above embodiments based on the essential technology of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An intracranial vascular implantation device, characterized in that: include: A mesh management stent, the mesh management stent comprising a plurality of mesh holes, the mesh management stent further comprising a distal portion, a middle portion and a proximal portion sequentially connected from the distal end to the proximal end along its own axial direction, the mesh holes of the proximal portion are smaller than the mesh holes of the middle portion, the mesh holes of the middle portion can pass blood flow, and the distal portion is in a trumpet shape that opens outward; as well as, A coating is disposed on at least a portion of the inner surface of the distal portion.

2. The intracranial vascular implantation device according to claim 1, characterized in that: The coating is provided with medicine for promoting endothelialization of the tumor neck.

3. The intracranial vascular implantation device according to claim 2, characterized in that: The drug is a growth factor that promotes endothelialization of the tumor neck. The drug is a drug solution containing the growth factor coated on the film. The concentration of the growth factor is 1 μg / mL to 100 μg / mL.

4. The intracranial vascular implantation device according to claim 3, characterized in that: The drug is coated on the film by at least one method of dipping, spraying and deposition.

5. The intracranial vascular implantation device according to claim 1, characterized in that: The plurality of grid holes include first diamond grid holes, second diamond grid holes and third diamond grid holes, the distal portion includes the first diamond grid holes and the second diamond grid holes, and / or the middle portion includes the first diamond grid holes and the second diamond grid holes, the first diamond grid holes and the second diamond grid holes have different aspect ratios, and the proximal portion includes the third diamond grid holes, and the third diamond grid holes have a preset aspect ratio.

6. The intracranial vascular implantation device according to claim 5, characterized in that: The aspect ratio of the first diamond-shaped mesh holes is 0.1 to 0.5, the aspect ratio of the second diamond-shaped mesh holes is 1.5 to 2.0, and the aspect ratio of the third diamond-shaped mesh holes is 0.5 to 1.

5.

7. The intracranial vascular implantation device according to claim 1, characterized in that: The length ratio of the distal portion, the middle portion and the proximal portion is (0.1-1):1:(1-2), and the length of the middle portion is 1.0 mm to 10 mm.

8. The intracranial vascular implantation device according to claim 1, characterized in that: The included angle between the flare of the distal end portion and the longitudinal axis of the network management support is 45° to 60°.

9. The intracranial vascular implantation device according to claim 1, characterized in that: The proximal end of the proximal part is configured as a trumpet mouth opening outwards, and the angle between the trumpet mouth of the proximal part and the longitudinal axis of the network management support does not exceed 45°.

10. The intracranial vascular implantation device according to claim 9, characterized in that: The included angle of the bell mouth of the proximal part is 30° to 45°.

11. The intracranial vascular implantation device according to claim 1, characterized in that: The proximal end of the proximal part is set as a bell mouth opening outward, the diameter of the bell mouth of the distal part is 4mm-15mm, the diameter of the middle part and the diameter of the part of the proximal part except the proximal bell mouth are both 1mm-5mm, and the diameter of the bell mouth of the proximal part is 4mm-8mm.

12. The intracranial vascular implantation device according to claim 1, characterized in that: The mesh hole density of the middle part is 0.01-0.5 holes / mm 2 The mesh hole density of the proximal part is 0.5 to 5 holes / mm 2 .

13. The intracranial vascular implantation device according to claim 1, characterized in that: The distal end portion is unfolded into a petal-shaped trumpet mouth, and 2 to 8 diamond-shaped grid holes are arranged along the circumference.

14. The intracranial vascular implantation device according to claim 1, characterized in that: The network management bracket is formed by integrally cutting from a metal pipe.

15. The intracranial vascular implantation device according to claim 1, characterized in that: The network management support also meets at least one of the following conditions: The distal end of the distal portion is provided with at least one developing point; The proximal end of the proximal portion is provided with at least one developing point; At least one developing point is provided at the junction of the distal portion and the middle portion; At least one developing point is arranged at the junction of the middle portion and the proximal portion.

16. The intracranial vascular implantation device according to claim 1, characterized in that: The diameter of the inscribed circle of the mesh holes in the middle portion for positioning in the bifurcated blood vessel is greater than or equal to the average diameter of the bifurcated blood vessel.

17. The intracranial vascular implantation device according to claim 1, characterized in that: The net management support as a whole adopts grid holes of the same shape, and the multiple grid holes distributed along the circumference of the net management support in the middle part are all connected by support rods.

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