CN117045412A

CN117045412A - Intracranial bifurcation aneurysm vascular stent conveyor and vascular stent

Info

Publication number: CN117045412A
Application number: CN202311169663.1A
Authority: CN
Inventors: 闵伟杰; 张桂运; 洪波; 刘建民
Original assignee: Shanghai First Peoples Hospital
Current assignee: Shanghai First Peoples Hospital
Priority date: 2023-09-11
Filing date: 2023-09-11
Publication date: 2023-11-14

Abstract

The application relates to the technical field of medical equipment, and particularly discloses an intra-intracranial bifurcation aneurysm intravascular stent conveyor and a intravascular stent. The conveyor comprises a bracket conveying end, wherein the bracket conveying end comprises a rear sheath tube, and a cap is arranged at the distal end of the rear sheath tube; the proximal end of the cap is provided with a loading area, and the bifurcation bracket is arranged in the loading area; the far end of the cap is closed, an axially arranged pushing rod is arranged in the loading area, and the bifurcation bracket is positioned in the loading area and sleeved on the pushing rod. The advantages are that: the Y-shaped stent can be used for treating the branch part aneurysm and the basilar artery tip branch part aneurysm in the intracranial brain, the integrated Y-shaped stent is conveyed into the branch part aneurysm, the expansion release of the main stent and the branch stent can be controlled by in vitro manual operation, the branch stent reaches the position of the branch blood vessel before the expansion release, and the expansion release stent is prevented from touching the side wall of the scratched blood vessel.

Description

Intracranial bifurcation aneurysm vascular stent conveyor and vascular stent

Technical Field

The application relates to the technical field of medical equipment, in particular to an intra-intracranial bifurcation aneurysm intravascular stent conveyor and a intravascular stent.

Background

The vascular stent is a tubular stent made of metal materials or polymer materials, and is placed in a narrow occlusion section blood vessel on the basis of balloon expansion forming so as to support the narrow occlusion section blood vessel, reduce elastic retraction and reshaping of the blood vessel, thereby keeping lumen blood flow smooth. Vascular stents are widely used in the treatment of vascular diseases such as coronary artery, intracranial artery, carotid artery, renal artery and femoral artery, and have remarkable therapeutic effects. Vascular stents are mainly divided into coronary, cardiac macrovascular stents, intracranial stents and peripheral vascular stents. The vascular stents are mainly divided into two main types according to the release mode, namely self-expanding stents and balloon-expanding stents; the self-expanding stent is a super-elastic net-shaped stent which is made of a nickel-titanium super-elastic alloy thin-wall tube through laser precise engraving, reaches a lesion through a pressing-holding type conveying catheter, self-expands after being released from fixation to enable blood to be smooth, and plays a supporting role on the lesion; the balloon expansion type stent is a stent which is made of medical stainless steel, cobalt-chromium alloy and the like and is sleeved on a balloon catheter in advance, the stent and the balloon are conveyed to a lesion site together, the balloon is pressurized and expanded to release the stent, and the expanded stent ensures that a lesion vessel is unblocked.

Aneurysms are a permanent distending disorder that occurs due to localized weakness of the arterial wall. Cerebral aneurysms are peripheral aneurysms, which are tumor-like protrusions generated by limited expansion of cerebral arterial walls, and the protruding aneurysm walls become thinner gradually under the continuous impact of blood flow and finally rupture and bleed. The intracranial stent is placed into an intracranial blood vessel by using an interventional treatment technology, so that an aneurysm is blocked, the smoothness of the artery carrying the aneurysm is kept, and the blood supply of a lesion area is recovered. Because of the minimally invasive stent surgery, the method has fewer complications and quicker recovery period, and is widely applied.

The existing used aneurysm vascular stent is mainly a straight stent, the vascular stent is implanted into a target area in a body by a conveyor, the conveyor for conveying the intracranial aneurysm vascular stent comprises a micro-catheter and a stent system arranged in the micro-catheter, and the self-expanding stent is released from the rear side of the micro-catheter through manual and manual in-vitro operation. In addition, the stent is released by means of a conveyor, the conveyor comprises an end head, a hollow inner tube, an outer tube and a handle assembly which are sleeved with each other, the hollow part of the inner tube is convenient for a guide wire to penetrate through the tube during operation, the vascular stent is compressed between the inner tube and the outer tube, the guide wire guides the catheter assembly of the conveying system to reach an operation position during operation, the outer tube is retracted by the handle control assembly, the compressed stent is exposed, and the stent can be directly expanded and released after being completely exposed. The working principle of the existing self-expanding vascular stent delivery device stent release is reported in a large number of documents, such as patents CN2015200012865, CN2020115071984 and CN2013103436499.

For a bifurcation aneurysm in the intracranial brain and a basilar artery sharp bifurcation aneurysm (as shown in fig. 1), the aneurysm is located at a bifurcation of a blood vessel, and two branch blood vessels need to be respectively placed into the branch blood vessels. The prior patent document discloses a plurality of Y-shaped vascular stents, for example, patent application number 2011201938711, a bifurcated stent with a membrane, which consists of a stent trunk and two stent branches, is of a Y-shaped structure as a whole and is bifurcated at the front end, however, the Y-shaped vascular stent belongs to a self-expanding stent, and the stent needs to be expanded under the help of an expanding instrument.

In addition, patent application No. 2018105217785, a Y-shaped carotid artery stent which can be absorbed from the branches of the tunica media comprises a main body part, a first branch part and a second branch part, wherein a delivery sheath is positioned at the Y-shaped structure of the artery along a guide wire during use, and the delivery sheath is withdrawn to release the Y-shaped arterial stent. Patent application number 2014203189970, a scalable bifurcation stent, including a trunk support and two bifurcation supports, trunk support and bifurcation support are linked together, are Y shape structure. Although the above two patent documents disclose Y-shaped vascular stents, there is no disclosure of how to deliver the Y-shaped vascular stent to a target area for release, and since the Y-shaped stent has a bifurcated structure, the total width of two bifurcated portions is generally greater than the width of the main stent, and the conventionally used delivery device cannot effectively load and release the main stent and the two bifurcated stents of the Y-shaped vascular stent simultaneously. At present, the Y-shaped intracranial stent is released by two stents together, and a gap is reserved between the two stents when the two stents are mutually extruded, so that blood flows into an aneurysm or thrombus is formed to cause cerebral infarction; or the second bracket is forced to stretch out from a certain mesh of the first bracket by adopting the mesh penetrating technology, the defect of mesh penetrating is that the shape of the first bracket is damaged, the covering effect is easy to be weakened, and the second bracket can be opened poorly and narrowly due to the opening in the mesh of the first bracket, thus leading to poor blood flow and other ending.

In addition, patent application number 2018202952614, a vascular bifurcation stent comprises a net-shaped stent main body and a yielding notch positioned on the side wall of the middle part of the vessel wall. The patent also actually adopts the scheme of two supports, and there is the breach of stepping down on the main part support, and the branch pipe support can release from the breach of stepping down, and this scheme has obvious defect, and the breach of main part support can just aim at another branch vessel in the operation of not knowing very accurately, and the alignment is not, and the second branch support just can not release very well or can not reach the purpose. At present, the release of the vascular stent cannot be realized at home and abroad, one side of the stent can just correspond to the wanted direction in the release process, and the stent can only be released in a mechanical way through a rollback release catheter or a way of pushing the stent out of the catheter, so that the direction cannot be mastered.

Patent application No. 2015200012865 discloses a guide rail structure applied to a vascular stent delivery system, patent application No. 2013103436499 discloses an implanted medical device delivery apparatus and a control method thereof. Both of these patent documents disclose the structure of the handle assembly (delivery unit) and the principle of controlling the release of the stent by the catheter unit through the handle assembly. Patent application No. 2020115071984 discloses a delivery device and a vascular stent system. The stent conveyers disclosed in the three patent documents cannot effectively load and compress the main stent and the two bifurcation stents of the Y-shaped vascular stent at the same time, and are not suitable for implantation of the Y-shaped vascular stent.

Patent application number 2018207239854, vascular stent conveying device and system thereof, patent application number 2004200193557 and Y-shaped vascular stent conveying system, the stent conveyers disclosed in the two patent application numbers can be used for conveying Y-shaped vascular stents, but when in use, branch stent guide wires are required to be respectively dissected and guided into bilateral femoral arteries of a patient, the branch stent guide wires are required to be completely pulled out of the body, and the conveyers cannot be used for treating intracranial bifurcation aneurysms and basilar artery sharp bifurcation aneurysms.

There is therefore a need for a stent delivery device and stent delivery system that can be used for intracranial and basilar bifurcation aneurysms.

Disclosure of Invention

The application aims to overcome the defects in the prior art and provide a vascular stent conveyor and a vascular stent conveying system which can be used for intracranial bifurcation aneurysms and basilar artery sharp bifurcation aneurysms.

In order to achieve the first object, the application adopts the following technical scheme:

an intracranial bifurcation aneurysm vascular stent conveyor is used for conveying a Y-shaped vascular stent, the Y-shaped vascular stent comprises a main stent, a first bifurcation stent and a second bifurcation stent, the front end of the main stent is bifurcated, and the bifurcation part of the main stent is respectively connected with the first bifurcation stent and the second bifurcation stent; the conveyer comprises a support conveying end, wherein the support conveying end comprises a rear sheath pipe, a loading area for loading a vascular support is arranged in the rear sheath pipe, the main support is arranged in the loading area, and a first cap and a second cap are arranged at the distal end of the rear sheath pipe; the proximal end of the first cap is provided with a first loading area, and the first bifurcation stent is arranged in the first loading area; the proximal end of the second cap is provided with a second loading area, and the second bifurcation bracket is arranged in the second loading area; the distal end of the first cap is closed, a first pushing rod which is axially arranged is arranged in the first loading area, and the first bifurcation bracket is positioned in the first loading area and sleeved on the first pushing rod; the distal end of the second cap is closed, a second pushing rod which is axially arranged is arranged in the second loading area, and the second bifurcation bracket is positioned in the second loading area and sleeved on the second pushing rod.

In the intracranial bifurcation aneurysm stent delivery device, preferably, the first cap, the second cap and the rear sheath are mutually independent; the first push rod is fixedly connected with the first cap, and the second push rod is fixedly connected with the first cap.

In the intracranial bifurcation aneurysm vascular stent delivery device, preferably, the delivery device further comprises a handle assembly, a driving device is arranged in the handle assembly, the driving device is connected with the rear sheath tube, the first cap and the second cap, the driving device is operated to control the first cap and the second cap to move distally, and the driving device is operated to control the rear sheath tube to move proximally.

In the above-described intracranial bifurcation stent delivery device, preferably, the driving means comprises a long tube axially disposed within the housing; a sliding piece capable of freely sliding is sleeved on the surface of the long tube, and the distal end of the sliding piece is connected with the rear sheath tube; a handle is arranged outside the shell and is connected with the proximal end of the sliding piece through a connecting rod, and the sliding handle controls the rear sheath tube to move towards the proximal end;

the novel multifunctional portable multifunctional electric power tool is characterized in that a rack which is axially arranged is arranged in the housing, the far end of the rack is connected with the first pushing rod and the first pushing rod, an opening is formed in the housing, a gear is arranged at the position of the opening, the gear is meshed with the rack, the edge of the gear penetrates through the opening to be exposed out of the housing, and the first cap and the second cap are controlled to move towards the far end through rotating the gear.

In the above-described intracranial bifurcation stent delivery device, preferably, the opening extends along the axial direction of the long tube.

In the intracranial bifurcation aneurysm stent delivery device, preferably, a handle opening is provided on the housing at a position corresponding to the long tube, the handle opening extends along the axial direction of the long tube, the connecting rod passes through the handle opening and is fixedly connected with the handle, and the handle can slide in a translational manner within the length range of the handle opening.

In the intracranial bifurcation aneurysm stent delivery device, preferably, the inner surface of the housing is provided with a sliding rail corresponding to the rack, and the front end and the rear end of the rack are embedded into the sliding rail, so that the rack can translate along the axial direction of the housing.

In the intracranial bifurcation aneurysm vascular stent delivery device, preferably, the outer sides of the first pushing rod and the second pushing rod are provided with radially arranged chucks, and the trunk stent is arranged in a region between the chucks and the caps in the loading region.

In the intracranial bifurcation stent delivery device, preferably, the distal longitudinal section of the rear sheath is in a right-angle structure, and the distal longitudinal section of the rear sheath comprises a supporting surface and a cladding surface, the supporting surface abuts against the proximal end surfaces of the first cap and the second cap, and the cladding surface covers the side surfaces, close to the proximal ends, of the first cap and the second cap.

In order to achieve the second purpose, the application adopts the following technical scheme:

the Y-shaped vascular stent comprises a main stent, a first bifurcation stent and a second bifurcation stent, wherein the front end of the main stent is bifurcated, the bifurcation part of the main stent is respectively connected with the first bifurcation stent and the second bifurcation stent, the first bifurcation stent is connected with the second bifurcation stent, and the grid density of the first bifurcation stent and the second bifurcation stent, which are close to the connection part, is greater than the grid density of the connection part far away from the connection part.

In the intracranial bifurcation aneurysm vascular stent, preferably, the first bifurcation stent and the second bifurcation stent are both composed of a dense mesh part and a sparse mesh part, the dense mesh part is arranged close to the bifurcation, the sparse mesh part is arranged far away from the bifurcation, the dense mesh part is of a reticular stent structure, the sparse mesh part is composed of a plurality of axial wires and fixed coils, the axial wires are distributed along the circumference of the bifurcation stent, the fixed coils comprise a first coil and a second coil, and the first coil and the second coil are respectively positioned at two end faces of the axial wires; preferably, the diameter of the first coil is smaller than the diameter of the second coil.

The application has the advantages that:

the device can be used for treating the branch part aneurysms and the basilar artery tip branch part aneurysms in the intracranial brain, skillfully designs a cap structure, can convey the integrated Y-shaped vascular stent into the branch part vascular, and the unreleased two branch stents are separately unfolded under the guidance of a guide wire to enter the branch vascular, so that the expansion release of the main stent and the branch stent in the main vascular and the branch vascular can be controlled successively through in vitro manual operation, the positions of the branch vascular are reached before the expansion release, and the expanded and released stents are prevented from touching the side wall of the scratched vascular.

Drawings

Fig. 1 is a photograph showing a blood vessel of an intracranial bifurcation aneurysm.

FIG. 2a is a schematic illustration of the structure of a Y-shaped stent of the present application (after expansion release).

FIG. 2b is a schematic illustration of the endovascular occlusion of a bifurcation aneurysm after the expansion release of the Y-stent of the present application.

FIG. 3 is a schematic diagram of the configuration of the intracranial bifurcation stent delivery device of the present application.

Fig. 4 is an enlarged schematic view of the area a in fig. 3.

Fig. 5a is a schematic view of the intracranial bifurcated aneurysm vascular stent delivery device of the present application beginning access to a bifurcated vessel.

Fig. 5b is a schematic view of the deployment of the two caps of the bifurcated intracranial aneurysm stent delivery device of the present application beginning under the guidance of a guidewire.

Fig. 5c is a schematic illustration of the release of the inflation of the main stent with the back sheath retracted.

Fig. 5d is a schematic view of the first and second caps being pushed forward to progressively expose the first and second bifurcated stents.

Fig. 5e is a schematic illustration of the first bifurcated stent and the second bifurcated stent fully expanded and released.

FIG. 6 is a schematic diagram of another embodiment of an intracranial bifurcation stent delivery device.

Fig. 7 is an enlarged schematic view of the area a in fig. 6.

The reference numerals and components referred to in the above figures are as follows:

y-shaped vascular stent 101, main stent 102, first bifurcation stent

103. Second bifurcated stent 104. Open mesh portion 105. Close mesh portion

106. Axial wire 107, first coil 108, second coil

200. Stent delivery end 201, rear sheath 202, first cap

203. Second cap 204. First push rod 205. Second push rod

206. Chuck 207, support surface 208, cladding surface

300. Handle assembly 301, housing 302, long tube

303. Slide 304, handle 305, connecting rod

306. Racks 307, handle openings 308, gears

109. Developing yarn

Detailed Description

The application is further described below in conjunction with the detailed description. It is to be understood that these examples are illustrative of the present application and are not intended to limit the scope of the present application. Further, it is understood that various changes and modifications of the present application may be made by those skilled in the art after reading the description of the present application, and such equivalents are intended to fall within the scope of the application as defined in the appended claims.

Example 1 intracranial bifurcation aneurysm vascular stent delivery

Definition "proximal" in the present application refers to the side relatively close to the operator. "distal" in this application refers to the side that is relatively far from the operator.

The vascular stent conveyor is used for conveying an integrated Y-shaped vascular stent to a bifurcation vascular target area, wherein the Y-shaped vascular stent has a structure shown in figure 2a and comprises a main stent, a first bifurcation stent and a second bifurcation stent, the main stent, the first bifurcation stent and the second bifurcation stent are bare stents or covered stents, and a plurality of wave rings are axially connected to form a reticular stent. The front end of the main support is bifurcated, and the bifurcation part of the main support is respectively connected with the first bifurcation support and the second bifurcation support. In the treatment of bifurcation aneurysms and basilar artery cusp bifurcation aneurysms, it is necessary to cover the bifurcation stent into the bifurcation vessel, and cover the main stent into the main vessel (the final effect is shown in fig. 2 b), and the existing vascular stent conveyor adopted is aimed at a straight vascular stent, and only the main stent can be loaded, and two bifurcation stents cannot be effectively loaded. If the main stent and the two bifurcation stents are simultaneously loaded into a rear sheath, the first bifurcation stent and the second bifurcation stent can only be simultaneously expanded and released when in use, and then the expanded and expanded first bifurcation stent and second bifurcation stent are pushed into two bifurcation vessels, the stent released by expansion in the process can touch the side wall of a scratched vessel, and dangerous events are easy to be caused, so that the prior vascular stent conveyor is not suitable for the intra-intracranial bifurcation aneurysm vessel.

The intracranial bifurcation aneurysm vascular stent conveyor structure is shown in fig. 3, the conveyor comprises a stent conveying end, the stent conveying end comprises a rear sheath, a loading area for loading the vascular stent is arranged in the rear sheath, and a main stent is arranged in the loading area in a compressed mode. The backbone stent is released by controlling the rear sheath to move proximally. When in use, the microcatheter is implanted firstly, the conveyer is conveyed to the vicinity of the target area in the body through the microcatheter channel, the proximal end of the rear sheath is exposed outside the body, and a doctor pulls the rear sheath backwards through manual operation to expose and expand the main stent for release. As shown in fig. 3, a first cap and a second cap are arranged at the distal end of the rear sheath, a first loading area is arranged at the proximal end of the first cap, and a first bifurcation stent is arranged in the first loading area; the proximal end of the second cap is provided with a second loading area, and the second bifurcation bracket is arranged in the second loading area; the distal end of the first cap is closed, a first pushing rod which is axially arranged is arranged in the first loading area, and the first bifurcation stent is compressed in the first loading area and sleeved on the first pushing rod; the distal end of the second cap is closed, a second pushing rod which is axially arranged is arranged in the second loading area, and the second bifurcation bracket is compressed in the second loading area and sleeved on the second pushing rod. When the device is used, the conveyor is conveyed to the vicinity of a target area in a human body through the micro-catheter channel, the proximal ends of the first pushing rod and the second pushing rod are exposed outside the human body, after the exposure expansion of the main stent is released, a doctor pushes the first pushing rod and the second pushing rod to the distal end through manual operation, and the first cap and the second cap are controlled to move to the distal end, so that the exposure expansion releases the two bifurcation stents.

In a specific embodiment of the present application, as shown in fig. 3, a radially disposed chuck is disposed at the outer sides of the first pushing rod and the second pushing rod, the trunk support is disposed in a region between the chuck and the cap in the loading area, the chuck is used for limiting the movement of the trunk support in the axial direction, the pushing rod is fixed during the process of pulling the rear sheath tube to release the trunk support, and the trunk support cannot move backwards along with the rear sheath tube due to the limitation of the chuck, so that the movement of the trunk support in the release process is avoided. Further preferably, the clamping head is in contact with the proximal end of the main support, or an axial reserved space is arranged between the clamping head and the proximal end of the main support, the length of the reserved space is greater than or equal to that of the cap, and the reserved space can be used for pushing the first pushing rod and the second pushing rod to the distal end.

In a specific embodiment of the present application, as shown in fig. 3, the distal end of the first pushing rod is fixedly connected to the first cap, and the distal end of the second pushing rod is fixedly connected to the second cap. The first pushing rod and the second pushing rod are controlled to translate distally relative to the bifurcated stent, so that the two bifurcated stents are exposed and released.

In a specific embodiment of the present application, the stent delivery end further includes a hollow inner tube, the main stent is disposed between the inner tube and the rear sheath, the first push rod and the second push rod are disposed in the inner tube, and a channel through which the guide wire passes is disposed at the centers of the first push rod and the second push rod.

In one embodiment of the present application, as shown in fig. 4, the distal longitudinal section of the rear sheath has a right-angle structure, and includes a supporting surface and a covering surface, wherein the supporting surface abuts against the proximal end surfaces of the first cap and the second cap, and the covering surface covers the proximal side surfaces of the first cap and the second cap. The stability of the whole conveyer can be improved through the coverage of the rear sheath, the whole conveyer can be pushed to a target area by pushing the rear sheath in the process of implanting the conveyer, and the two caps are prevented from being separated from each other and from being separated from the rear sheath in the pushing process. The exemplary cladding surface shown in fig. 4 covers the proximal end regions of the two caps, and in order to further enhance the overall structural stability of the conveyor, the cladding surface may be expanded to cover the middle or distal end regions of the two caps, and such improved structures are within the scope of the present application.

Referring to fig. 2a, in one embodiment of the present application, the first bifurcation stent and the second bifurcation stent at the bifurcation of the main stent are connected with each other, and the mesh density of the first bifurcation stent and the second bifurcation stent near the connection is greater than the mesh density of the second bifurcation stent far from the connection. That is, the grids of the bifurcated stent close to the bifurcation are dense, and the grids of the bifurcated stent far away from the bifurcation are sparse. As shown in fig. 1, there are many important branch vessels of the tiny brain stem in the two cerebral posterior arteries after the basilar artery is bifurcated, and if the overall grid of the Y-shaped vascular stent is too dense, the tiny vessels sent out on the lower blood vessel are blocked due to stent coverage; if the whole grid of the Y-shaped vascular stent is too sparse, the stent at the bifurcation part cannot effectively cover the tumor opening. According to the application, the bifurcation stent is arranged into a reticular structure with gradually reduced density, and the reticular bifurcation stent at the bifurcation part can effectively cover a tumor orifice and simultaneously, the reticular bifurcation stent far away from the bifurcation part can not block tiny blood vessels emitted on a lower blood vessel due to the reduced density, so that the bifurcation stent has the advantage of higher safety. Still more preferably, the first bifurcated stent and the second bifurcated stent are both composed of a dense mesh portion and a sparse mesh portion, the dense mesh portion is disposed close to the bifurcation, the sparse mesh portion is disposed far away from the bifurcation, the dense mesh portion is a mesh-shaped stent structure, the sparse mesh portion is composed of a plurality of axial wires and fixed coils, the number of the axial wires is 2-20, and the axial wires are approximately parallel to the axis of the bifurcated stent and are distributed along the circumference of the bifurcated stent; preferably the number of axial wires is 2, 4, 6, 8, 10, 12, 14, 16, 18, 20. The fixed coil comprises a first coil and a second coil, the first coil and the second coil are respectively positioned on two end faces of the axial silk thread, the first coil is far away from the bifurcation, and the second coil is connected with the dense net part. The structural design of the axial hard wire and the fixed coil further effectively avoids the interference to the tiny blood vessels of the lower blood vessels while maintaining the stability of the bifurcation stent, and further improves the safety of the stent.

The application discloses a using method of an intracranial bifurcation aneurysm vascular stent conveyer, which comprises the following steps:

(1) The Y-shaped vascular stent is compressed and loaded at the stent delivery end, the trunk stent is compressed and arranged in the loading area of the rear sheath, the first bifurcation stent is arranged in the first loading area, and the second bifurcation stent is arranged in the second loading area. Microcatheters are first implanted and the delivery device is delivered through the microcatheter channel to the vicinity of the target area in the body (fig. 5 a).

(2) Continuing to push the stent delivery end distally, the first cap and second cap guide wires begin to deploy and separate into the bifurcated vessel (fig. 5 b).

(3) The fixed push rod is not moved, and the back sheath is pulled backwards through manual operation, so that the main stent is exposed, expanded and released (fig. 5 c).

(4) After the fixation, the sheath is immobilized, the first pushing rod and the second pushing rod are pushed to the distal end, and the first cap and the second cap are controlled to move to the distal end, so that the two bifurcation brackets are gradually exposed (fig. 5 d).

(5) The first bifurcated stent and the second bifurcated stent are automatically expanded and released after exposure (fig. 5 e).

(6) Exiting the entire conveyor.

Example 2 intracranial bifurcation aneurysm stent delivery (with handle)

In order to facilitate the release of the support, a conveyer handle capable of controlling the back sheath tube to retreat and the push rod to push forwards is designed, the conveyer handle is connected with the conveying end of the support, the conveying end of the support is placed into the body during use, the handle is left outside the body, and the release of the support is controlled by operating the handle. The vascular stent conveyor of the embodiment is used for conveying an integrated Y-shaped vascular stent to a bifurcation vascular target area, wherein the Y-shaped vascular stent has a structure shown in fig. 1 and embodiment 1 and comprises a main stent, a first bifurcation stent and a second bifurcation stent, the front end of the main stent is bifurcated, and the bifurcation part of the main stent is respectively connected with the first bifurcation stent and the second bifurcation stent. The intracranial bifurcation aneurysm vascular stent conveyer structure is as shown in fig. 6, 7 and 3, the conveyer comprises a stent conveying end and a handle assembly, the stent conveying end comprises a rear sheath, a loading area for loading the vascular stent is arranged in the rear sheath, and a main stent is arranged in the loading area in a compressed mode. The backbone stent is released by controlling the rear sheath to move proximally. The specific structure of the handle assembly to control the movement of the rear sheath in this embodiment is well documented in the prior art, such as CN2015200012865, CN2013103436499 and CN2020115071984, and the handle and sliding member control the translation of the rear sheath relative to the backbone stent to expose the released backbone stent.

Referring to fig. 3, a first cap and a second cap are disposed at the distal end of the rear sheath, a first loading area is disposed at the proximal end of the first cap, and a first bifurcation stent is disposed in the first loading area; the proximal end of the second cap is provided with a second loading area, and the second bifurcation bracket is arranged in the second loading area; a drive device within the handle assembly is coupled to the first cap and the second cap and is operable to drive movement of the sheath, and the first cap and the second cap are controlled to move distally by operation of the handle assembly to release the two bifurcated stents.

Referring to fig. 3, in a specific embodiment of the present application, the distal end of the first cap is closed, a first pushing rod axially disposed is disposed in the first loading area, and the first bifurcated stent is disposed in the first loading area and sleeved on the first pushing rod; the distal end of the second cap is closed, a second pushing rod which is axially arranged is arranged in the second loading area, and the second bifurcation bracket is positioned in the second loading area and sleeved on the second pushing rod. The first push rod is fixedly connected with the first cap, and the second push rod is fixedly connected with the first cap. A drive mechanism within the handle assembly is coupled to the first push rod and the second push rod for controlling distal translation of the first push rod and the second push rod relative to the bifurcated stent to thereby expose release of the two bifurcated stents.

In one embodiment of the application, as shown in fig. 6 and 7, the driving means comprises a long tube axially disposed within the housing; a sliding piece capable of freely sliding is sleeved on the surface of the long tube, and the distal end of the sliding piece is connected with the rear sheath tube; a handle is arranged outside the shell and is connected with the proximal end of the sliding piece through a connecting rod, and the sliding handle controls the rear sheath tube to move towards the proximal end; further preferably, a handle opening is arranged at a position on the shell corresponding to the long tube, the handle opening extends along the axial direction of the long tube, the connecting rod penetrates through the handle opening to be fixedly connected with the handle, and the handle can slide in a translational manner within the length range of the handle opening.

In one embodiment of the application, as shown in fig. 6, the housing is elongated and hollow, the long tube is disposed parallel to the axis of the housing, the proximal end of the long tube extends out from the proximal end of the housing, and a long sleeve is attached to the proximal end of the long tube. Preferably, the proximal end of the long tube is fixedly connected with the housing.

In one embodiment of the present application, as shown in fig. 6 and 7, a rack is disposed in the housing, a distal end of the rack is connected to the first pushing rod and the first pushing rod, an opening is disposed on the housing, a gear is disposed at the position of the opening, the gear is engaged with the rack, an edge of the gear is exposed outside the housing through the opening, and the first cap and the second cap are controlled to move distally by rotating the gear, thereby exposing and releasing the two bifurcated brackets. Further preferably, the inner surface of the shell is provided with a sliding rail corresponding to the rack, and the front end and the rear end of the rack are embedded into the sliding rail, so that the rack can translate along the axial direction of the shell.

In one embodiment of the application, the gear comprises a first gear and a second gear which are arranged in parallel, and a trolley which is arranged between the first gear and the second gear and rotates coaxially, wherein the edge of the trolley is exposed out of the shell through the opening. The rack comprises a first rack and a second rack, the first rack and the second rack are respectively meshed with the first gear and the second gear, and the distal ends of the first rack and the second rack are respectively connected with the proximal ends of the first pushing rod and the first pushing rod. The translation of the first cap and the second cap can be simultaneously controlled by rotating the trolley.

In a specific embodiment of the present application, the stent delivery end further includes a hollow inner tube, a proximal end of the inner tube is fixedly connected with a distal end of the long tube, the main stent is disposed between the inner tube and the rear sheath, proximal ends of the first push rod and the second push rod are disposed in the inner tube, and a channel through which the guiding wire passes is disposed at a center of the first push rod, the second push rod, and the inner tube.

As shown in fig. 3, in a specific embodiment, the outer sides of the first pushing rod and the second pushing rod are provided with a radially arranged chuck, the trunk support is arranged in a loading area and located in an area between the chuck and the cap, the chuck is used for limiting the movement of the trunk support in the axial direction, the pushing rod is fixed in the process of releasing the trunk support by pulling the rear sheath backwards, and the trunk support cannot move backwards along with the rear sheath due to the limitation of the chuck, so that the movement of the trunk support in the releasing process is avoided. Further preferably, the clamping head is in contact with the proximal end of the main support, or an axial reserved space is arranged between the clamping head and the proximal end of the main support, the length of the reserved space is greater than or equal to that of the cap, and the reserved space can be used for pushing the first pushing rod and the second pushing rod to the distal end.

In one embodiment of the present application, as shown in fig. 4, the distal longitudinal section of the rear sheath has a right-angle structure, and includes a supporting surface and a covering surface, wherein the supporting surface abuts against the proximal end surfaces of the first cap and the second cap, and the covering surface covers the proximal side surfaces of the first cap and the second cap. The stability of the whole conveyer can be improved through the coverage of the rear sheath, the whole conveyer can be pushed to a target area by pushing the rear sheath in the process of implanting the conveyer, and the two caps are prevented from being separated from each other and from being separated from the rear sheath in the pushing process.

Referring to fig. 2, in one embodiment of the present application, the first bifurcation stent and the second bifurcation stent at the bifurcation of the main stent are connected with each other, and the mesh density of the first bifurcation stent and the second bifurcation stent near the connection is greater than the mesh density of the second bifurcation stent far from the connection. That is, the grids of the bifurcated stent close to the bifurcation are dense, and the grids of the bifurcated stent far away from the bifurcation are sparse. As shown in fig. 1, there are many important branch vessels of the tiny brain stem in the two cerebral posterior arteries after the basilar artery is bifurcated, and if the overall grid of the Y-shaped vascular stent is too dense, the tiny vessels sent out on the lower blood vessel are blocked due to stent coverage; if the whole grid of the Y-shaped vascular stent is too sparse, the stent at the bifurcation part can not effectively cover the tumor opening. According to the application, the bifurcation stent is arranged into a reticular structure with gradually reduced density, and the reticular bifurcation stent at the bifurcation part can effectively cover a tumor orifice and simultaneously is far away from the bifurcation part, so that the reticular bifurcation stent with smaller density can not block tiny blood vessels emitted from lower blood vessels, and has the advantage of higher safety. Still further preferably, the bifurcation stent close to the bifurcation is a reticular stent structure, and the bifurcation stent far away from the bifurcation is a structure of a single-strand axial hard wire and a fixed coil, and the structure can further effectively avoid the interference to the tiny blood vessels of the lower blood vessels, and further improve the safety of the stent.

(1) The Y-shaped vascular stent is compressed and loaded at the stent delivery end, the trunk stent is compressed and arranged in the loading area of the rear sheath, the first bifurcation stent is arranged in the first loading area, the second bifurcation stent is arranged in the second loading area, and the stent delivery end is moved to the vicinity of the bifurcation vessel to be placed by pushing the whole conveyor (fig. 5 a);

(3) The posterior sheath is controlled by the handle and slider to translate proximally relative to the main stent, thereby exposing the main stent, which is then expanded for release (fig. 5 c).

(4) The first cap and the second cap are controlled to move distally by rotating the gear, thereby exposing and releasing the two bifurcated stents, which are then expanded and released after exposure (fig. 5d-5 e).

(5) And exiting the conveyor.

Example 3 vascular stent delivery System

The vascular stent delivery system comprises the intracranial bifurcation aneurysm vascular stent delivery device described in the embodiment 1-2 and the integrated Y-shaped vascular stent described in the embodiment 1-2 which is arranged in the stent delivery end, and the Y-shaped vascular stent can be delivered to the bifurcation aneurysm and basilar artery apex bifurcation aneurysm blood vessel in the intracranial brain through the vascular stent delivery device.

Example 4 Integrated Y-shaped vascular stent for bifurcation aneurysms in the intracranial brain and basilar apex bifurcation aneurysms

Referring to fig. 2a, the integrated Y-shaped vascular stent comprises a main stent, a first bifurcation stent and a second bifurcation stent, wherein the front end of the main stent is bifurcated, the bifurcation part of the main stent is connected with the first bifurcation stent and the second bifurcation stent respectively, the first bifurcation stent is connected with the second bifurcation stent, and the grid density of the first bifurcation stent and the second bifurcation stent close to the connection part is greater than the grid density of the grid far away from the connection part. That is, the grids of the bifurcated stent close to the bifurcation are dense, and the grids of the bifurcated stent far away from the bifurcation are sparse. Preferably, the grid density of the first bifurcation stent and the second bifurcation stent near the connection point is 2-6 times that of the grid density of the first bifurcation stent and the second bifurcation stent far away from the connection point, and more preferably, the grid density of the first bifurcation stent and the second bifurcation stent near the connection point is 3 times that of the grid density of the first bifurcation stent and the second bifurcation stent far away from the connection point. The bifurcation stent is arranged into a reticular structure with gradually reduced density, and the reticular bifurcation stent at the bifurcation part effectively covers a tumor orifice and simultaneously is far away from the reticular bifurcation stent at the bifurcation part, so that tiny blood vessels sent on subordinate blood vessels can not be blocked due to the smaller density, and the bifurcation stent has the advantage of higher safety. Still more preferably, the first bifurcated stent and the second bifurcated stent are both composed of a dense mesh portion and a sparse mesh portion, the dense mesh portion is disposed close to the bifurcation, the sparse mesh portion is disposed far away from the bifurcation, the dense mesh portion is a mesh-shaped stent structure, the sparse mesh portion is composed of a plurality of axial wires and fixed coils, the number of the axial wires is 2-20, and the axial wires are approximately parallel to the axis of the bifurcated stent and are distributed along the circumference of the bifurcated stent; preferably the number of axial wires is 2, 4, 6, 8, 10, 12, 14, 16, 18, 20. The fixed coil comprises a first coil and a second coil, the first coil and the second coil are respectively positioned on two end faces of the axial silk thread, the first coil is far away from the bifurcation, and the second coil is connected with the dense net part. The structural design of the axial hard wire and the fixed coil further effectively avoids the interference to the tiny blood vessels of the lower blood vessels while maintaining the stability of the bifurcation stent, and further improves the safety of the stent.

Referring to fig. 2a, in a specific embodiment, the diameter of the first coil is smaller than that of the second coil, the second coil is connected with the dense net portion and the main support, the length of the second coil connected with the dense net portion is 20% -80% of the whole length of the second coil, and the diameter of the second coil is 1.1-2.0 times of that of the first coil. The Y-shaped vascular stent bifurcation opening can be enlarged in the design, the second coil is larger than the bifurcation vessel in size, the position, close to the proximal end, of the second coil can be clamped outside the bifurcation vessel, the second coil is prevented from entering the bifurcation vessel, the main stent is prevented from covering the bifurcation vessel opening, which is caused by the bifurcation vessel opening, and the use safety of the stent is improved.

Referring to fig. 2a, in one embodiment, the main stent, the first bifurcated stent and the second bifurcated stent are provided with spiral developing filaments.

The technical features of the foregoing embodiments of the present application may be combined in any desired manner, and for brevity and understanding of description, all possible combinations of the technical features of the foregoing embodiments are not listed one by one, however, as long as there is no technical contradiction between the combinations of the technical features, it should be considered that the possible combinations of the technical features belong to the description ranges of the embodiments and the summary of the application, and belong to the protection range of the claims of the present application.

The foregoing is merely a preferred embodiment of the present application, and it should be noted that modifications and additions may be made to those skilled in the art without departing from the method of the present application, which modifications and additions are also to be considered as within the scope of the present application.

Claims

1. An intracranial bifurcation aneurysm vascular stent conveyor is used for conveying a Y-shaped vascular stent, the Y-shaped vascular stent comprises a main stent, a first bifurcation stent and a second bifurcation stent, the front end of the main stent is bifurcated, and the bifurcation part of the main stent is respectively connected with the first bifurcation stent and the second bifurcation stent; the conveyer comprises a support conveying end, wherein the support conveying end comprises a rear sheath pipe, a loading area for loading a vascular support is arranged in the rear sheath pipe, and the conveyer is characterized in that the main support is arranged in the loading area, and a first cap and a second cap are arranged at the distal end of the rear sheath pipe; the proximal end of the first cap is provided with a first loading area, and the first bifurcation stent is arranged in the first loading area; the proximal end of the second cap is provided with a second loading area, and the second bifurcation bracket is arranged in the second loading area; the distal end of the first cap is closed, a first pushing rod which is axially arranged is arranged in the first loading area, and the first bifurcation bracket is positioned in the first loading area and sleeved on the first pushing rod; the distal end of the second cap is closed, a second pushing rod which is axially arranged is arranged in the second loading area, and the second bifurcation bracket is positioned in the second loading area and sleeved on the second pushing rod.

2. The intracranial bifurcation stent delivery device according to claim 1, wherein the first cap, the second cap, and the posterior sheath are independent of each other; the first push rod is fixedly connected with the first cap, and the second push rod is fixedly connected with the first cap.

3. The intracranial bifurcation stent delivery device as recited in claim 2, further comprising a handle assembly having a drive mechanism disposed therein, the drive mechanism being coupled to the posterior sheath, the first cap and the second cap being controlled to move distally by operation of the drive mechanism, the posterior sheath being controlled to move proximally by operation of the drive mechanism.

4. The intracranial bifurcation aneurysm stent delivery device according to claim 3, wherein the driving means comprises a long tube axially disposed within the housing; a sliding piece capable of freely sliding is sleeved on the surface of the long tube, and the distal end of the sliding piece is connected with the rear sheath tube; a handle is arranged outside the shell and is connected with the proximal end of the sliding piece through a connecting rod, and the sliding handle controls the rear sheath tube to move towards the proximal end;

5. The intracranial bifurcated aneurysm stent delivery device according to claim 4, wherein the opening extends along the axial direction of the elongate tube.

6. The intracranial bifurcation stent delivery device according to claim 4, wherein the housing is provided with a handle opening at a position corresponding to the long tube, the handle opening extending along the axial direction of the long tube, the connecting rod passing through the handle opening and fixedly connected to the handle, the handle being slidably translatable within the length of the handle opening.

7. The intracranial bifurcation stent-graft delivery device according to claim 4, wherein the housing has an inner surface provided with a sliding rail corresponding to the rack, and the rack is embedded in the sliding rail at its front and rear ends so that the rack can translate along the axial direction of the housing.

8. The intracranial bifurcation stent delivery device according to any one of claims 1-7, wherein radially disposed clips are provided on the outer sides of the first push rod and the second push rod, and the backbone stent is disposed in a region between the clips and the cap in the loading zone; the longitudinal section of the distal end of the rear sheath tube is of a right-angle structure and comprises a supporting surface and a cladding surface, the supporting surface is propped against the proximal end surfaces of the first cap and the second cap, and the cladding surface covers the side surfaces, close to the proximal ends, of the first cap and the second cap.

9. The Y-shaped vascular stent comprises a main stent, a first bifurcation stent and a second bifurcation stent, wherein the front end of the main stent is bifurcated, the bifurcation part of the main stent is respectively connected with the first bifurcation stent and the second bifurcation stent, and the first bifurcation stent is mutually connected with the second bifurcation stent.

10. The intracranial bifurcation aneurysm vascular stent according to claim 9, wherein the first bifurcation stent and the second bifurcation stent are composed of a dense mesh portion and a sparse mesh portion, the dense mesh portion is arranged close to the bifurcation, the sparse mesh portion is arranged far away from the bifurcation, the dense mesh portion is of a mesh-shaped stent structure, the sparse mesh portion is composed of a plurality of axial wires and fixed coils, the axial wires are distributed along the circumference of the bifurcation stent, the fixed coils comprise a first coil and a second coil, and the first coil and the second coil are respectively positioned on two end faces of the axial wires; preferably, the diameter of the first coil is smaller than the diameter of the second coil.