Double-guide-wire conveying system of self-expanding bracketTechnical Field
The invention relates to the technical field of medical appliances, in particular to a double-guide wire conveying system of a self-expanding bracket.
Background
Intracranial aneurysms are a common cerebrovascular disease with high mortality and high disability rate, and with the advancement of medical science, endovascular treatment has become the first choice for intracranial aneurysms, wherein the intracranial aneurysms are treated by adopting a blood flow guiding device, namely a self-expanding stent is pre-installed in a delivery system and is delivered to a lesion site through a catheter or a micro-catheter, and the stent is released; however, for self-expanding stents, because of the high elasticity of the stent, the stent cannot be pressed or bound on the delivery system, but is delivered to the lesion site by friction or thrust through components on the delivery system; this approach can result in a large resistance during the pushing process, making it difficult for the stent to reach the lesion site, and even for the stent to deform during the pushing process due to a large friction force, and thus the stent cannot be used.
Disclosure of Invention
1. Technical problem to be solved
The invention solves the technical problems that the invention overcomes the problems in the prior art that the bracket is sent to the lesion part by friction force or thrust; the double-guide wire conveying system of the self-expanding stent has the characteristics of greatly reducing the resistance of the device in the pushing process, shortening the operation time, having simple structure and being easy to control and ensure the molding process and performance.
2. Technical proposal
In order to achieve the above purpose, the present invention provides the following technical solutions: a dual guidewire delivery system of a self-expanding stent, comprising a first delivery guidewire system comprising a first delivery guidewire and a sheath, and a second delivery guidewire system comprising a second delivery guidewire, a first restriction member, a second restriction member, and a third restriction member; the upper end of the first conveying guide wire is integrally formed with the sheath tube, the lower end of the sheath tube is provided with a through hole, the diameter of the through hole is matched with the diameter of the second conveying guide wire, an installation cavity B is formed in the sheath tube, the elastic support is arranged in the installation cavity B, the upper end of the sheath tube is integrally formed with the arc-shaped part, and the second guide wire is connected with the first limiting part, the second limiting part and the third limiting part; the elastic support is arranged between the first limiting part and the third limiting part and is pressed on the second limiting part; the first restriction member, the second restriction member, and the third restriction member are developable under X-rays; the sheath is placed inside the catheter and the catheter is placed inside the blood vessel.
The dual guidewire delivery system of a self-expanding stent described above wherein the first delivery guidewire is in a parallel relationship with the second delivery guidewire.
In the dual-guidewire delivery system of the self-expanding stent, the diameter of the first limiting member is larger than the outer diameter of the elastic stent in the installation cavity B, and the diameter of the first limiting member is smaller than the inner diameter of the sheath.
The self-expanding stent double-guide wire conveying system is characterized in that the second limiting part is an elastic annular part and is fixed on the second guide wire, the shape of the second limiting part can be cylindrical, spherical, conical or special-shaped with protrusions, the second limiting part is in interference fit with the elastic stent in the mounting cavity B, and the maximum outer diameter of the second limiting part is smaller than the inner diameter of the sheath.
The self-expanding stent dual guidewire delivery system described above, wherein the second restriction member may be one or more.
In the double-guide wire conveying system of the self-expanding stent, the diameter of the third limiting component is smaller than the inner diameter of the sheath, and the upper edge of the third limiting component coincides with the upper edge of the sheath.
The double-guide-wire conveying system of the self-expanding stent comprises a sheath tube, wherein the sheath tube is of a tubular structure made of high polymer materials, the size of an inner installation cavity B of the sheath tube is matched with that of an elastic stent, and meanwhile, the sheath tube is made of one or more of PTFE, FEP, fluorinated ethylene propylene copolymer, POM, nylon, pebax, polyimide, polyurethane, polyester, polyethylene, polyvinyl chloride and coated polyvinylpyrrolidone.
The second limiting member may be a developing material, such as silica gel, TPU, rubber, PI, pebax, nylon, PC, PE, PVC, thermoplastic elastomer, polyamide, polytetrafluoroethylene, polypropylene, polymethyl methacrylate, polyethylene terephthalate, polyvinylpyrrolidone, polyvinyl alcohol, epoxy resin, acrylic ester and acrylic ester derivatives, or a developing metal material, such as gold, amber, tungsten pure metal material and related alloy material, or one or more of the above polymer materials and metal materials.
In the double-guide wire conveying system of the self-expanding stent, the elastic stent is of a cylindrical structure made of nickel-titanium alloy or polymer with memory, and the size of the sheath tube is matched with the size of the inner cavity.
3. Advantageous effects
In summary, the beneficial effects of the invention are as follows:
(1) The stent is contained in the sheath tube for conveying, so that the resistance in the stent conveying process is greatly reduced, and the deformation in the stent conveying process is avoided;
(2) The upper end of the catheter sheath is an arc-shaped part, so that the inner wall of the micro-catheter is prevented from being scratched when the catheter sheath moves;
(3) The first limiting component, the second limiting component and the third limiting component have developability, so that doctors can conveniently observe the specific position of the sheath tube in the blood vessel, and the accuracy of the mounting position of the elastic support is improved;
(4) The second limiting member is effective to secure the stent within the sheath such that the delivery system has a retractable function to readjust the position of the stent during stent release.
Drawings
FIG. 1 is a schematic elevational view of the structure of the present invention;
FIGS. 2-5 are schematic diagrams illustrating the operation of the structure of the present invention;
FIG. 6 is an enlarged schematic view of the present invention at structure A;
FIG. 7 is a top plan view of the structure of the present invention;
FIG. 8 is a bottom view of the structure of the present invention;
FIG. 9 is an external view of the structure of the present invention;
FIG. 10 illustrates several shapes of the second restriction device in the structure of the present invention; 10A is a cylindrical front view and a side view, and 10B is a conical front view and a side view; 10C is a cake-shaped front view and a side view, and 10D is a spherical front view and a side view;
fig. 11 is a profile of a second limiting member of the present invention.
In the figure: 1. a second delivery guidewire; 2. a third restriction member; 3. an elastic support; 4. a second restriction member; 5. a sheath; 6. a first restriction member; 7. a first delivery guidewire; 8. a through hole; 9. a catheter or microcatheter; 10. a blood vessel; 11. an arc-shaped part.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Referring to fig. 2-5, the present invention provides a technical solution: a double-guide wire conveying system of a self-expanding bracket, which comprises a first conveying guide wire system and a second conveying guide wire system, wherein the first conveying guide wire system comprises a first conveying guide wire 7 and a sheath 5, and the second conveying guide wire system comprises a second conveying guide wire 1, a first limiting part 6, a second limiting part 4 and a third limiting part 2; the upper end of the first conveying guide wire 7 is integrally formed or fixedly connected with the sheath tube 5, the lower end of the sheath tube 5 is provided with a through hole 8, meanwhile, the diameter of the through hole 8 is matched with that of the second conveying guide wire 1, the inside of the sheath tube 5 is provided with an installation cavity B, the elastic support 3 is arranged in the installation cavity B, the upper end of the sheath tube 5 is integrally formed with the arc-shaped part 11, and the second guide wire 1 is connected with the first limiting part 6, the second limiting part 4 and the third limiting part 2; the elastic support 3 is arranged between the first limiting part 6 and the third limiting part 2 and is pressed on the second limiting part 4; the first restriction member 6, the second restriction member 4, and the third restriction member 2 can be developed under X-rays.
The first conveying guide wire 7 is in parallel relation with the second conveying guide wire 1; the diameter of the first limiting part 6 is larger than the outer diameter of the elastic support 3 in the mounting cavity B, and the diameter of the first limiting part 6 is smaller than the inner diameter of the sheath tube 5; the second limiting component 4 is an elastic annular component, is fixed on the second guide wire 1, can be cylindrical, spherical, conical or special-shaped with protrusions, and is in interference fit with the bracket 3 in the installation cavity B, the maximum outer diameter is smaller than the inner diameter of the sheath tube 5, and the second limiting component 4 can be one or more; the diameter of the third limiting part 2 is smaller than the inner diameter of the sheath tube 5, and the upper edge of the third limiting part is overlapped with the upper edge of the sheath tube 5; the sheath tube 5 is of a tubular structure made of high polymer materials, the size of the inner installation cavity B of the sheath tube 5 is matched with the size of the elastic support 3, and meanwhile, the sheath tube 5 is made of one or more of PTFE, FEP, fluorinated ethylene propylene copolymer and other fluorine-containing materials, POM, nylon, pebax, polyimide, polyurethane, polyester, polyethylene, polyvinyl chloride, coated polyvinylpyrrolidone and the like; the second limiting member 4 is a developable material, and may be a silica gel, TPU, rubber, PI, pebax, nylon, PC, PE, PVC, thermoplastic elastomer, polyamide, polytetrafluoroethylene, polypropylene, polymethyl methacrylate, polyethylene terephthalate, polyvinylpyrrolidone, polyvinyl alcohol, epoxy resin, acrylic ester derivative, or a metal material with good development such as gold, amber, tungsten pure metal material, or a related alloy material, or one or more of the above-mentioned high molecular materials and metal materials; the elastic support 3 is of a cylindrical structure made of nickel-titanium alloy, and the size of the sheath 5 is matched with the size of the inner cavity; the sheath 5 is placed inside the catheter 9, and the catheter 9 is placed inside the blood vessel 10.
As shown in fig. 6: in order to avoid the damage of the front end of the sheath tube 5 to the inner wall of the micro-catheter, the upper end of the sheath tube 5 is provided with an arc-shaped part 11, so that the inner wall of the micro-catheter is prevented from being scratched, the structure is simple, and the implementation is convenient;
as shown in fig. 2, the catheter or the micro-catheter 9 reaches the lesion position first, the dual-guide wire conveying system of the invention is used for simultaneously pushing the first guide wire and the second guide wire to enable the stent 3 to be along the lesion position of the catheter or the micro-catheter 9, whether the dual-guide wire system reaches the target position or not can be determined through the developability of the third limiting component 2 under the X-ray, and when the upper edge of the third limiting component 2 coincides with the edge of the opening end of the catheter or the micro-catheter 9, the dual-guide wire system of the invention reaches the target position is shown in fig. 3; fixing the positions of the catheter or micro-catheter 9 and the first conveying guide wire 7, pushing the second conveying guide wire 1 to move forwards, starting to release the stent 3 by the pushing force of the first limiting component 6 and the friction force with the second limiting component 4, enlarging the diameter, and performing a stretching operation on the blood vessel 10, as shown in fig. 4, under the mutual matching of the catheter or micro-catheter 9, the first conveying guide wire system and the second conveying guide wire system (retracting the catheter or micro-catheter 9, the first conveying guide wire system or pushing the second conveying guide wire system forwards) until the upper edge of the first limiting component 6 completely exceeds the outlet edges of the sheath 5 and the catheter or micro-catheter 9, so that the stent 3 is completely released, and performing the stretching operation on the blood vessel 10, as shown in fig. 5; because the second limiting part 4 has strong friction force on the stent 3, when the upper edge of the second limiting part 4 does not exceed the edge of the sheath outlet, the conveying system has a retractable function, the stent is retracted into the sheath 5 again, and the position of the stent is readjusted in the stent releasing process; the self-expanding stent double-guide wire conveying system has the advantages that the whole working process of the self-expanding stent double-guide wire conveying system is realized, the resistance of the stent in the pushing process is greatly reduced, the operation time is shortened, the structure is simple, and the forming process and the performance are easy to control and ensure.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.