CN113712712B - Intracranial aneurysm embolism auxiliary stand and conveying system - Google Patents

Abstract

The invention belongs to the technical field of medical appliances, in particular to the A61F2/90 field, and particularly relates to an intracranial aneurysm embolism auxiliary bracket and a conveying system. The invention provides an auxiliary support for intracranial aneurysm embolism, which comprises a support main body, wherein the support main body is of a hollow cylindrical structure, the side wall of the cylindrical structure of the support main body is of a net structure, the distal end part of the support main body is of a closed-loop support, and the proximal end part of the support main body is of an open-loop support; the axial length of the closed loop bracket part accounts for 1/2-2/3 of the axial length of the bracket main body. Through the setting of open-loop support and closed-loop support's combination, the support can be enough partial release recoverable, can have better adherence nature again, anti bending nature, prevents the performance of shifting.

Description

Intracranial aneurysm embolism auxiliary stand and conveying system

Technical Field

The invention belongs to the technical field of medical appliances, in particular to the A61F2/90 field, and particularly relates to an intracranial aneurysm embolism auxiliary bracket and a conveying system.

Background

Intracranial aneurysms are usually abnormal bulging occurring on the wall of intracranial arteries, which is the first cause of subarachnoid hemorrhage, and in cerebrovascular accidents, the first cause is cerebral thrombosis and hypertensive cerebral hemorrhage, and the third cause is cerebral thrombosis and hypertensive cerebral hemorrhage. The current treatment of intracranial aneurysms is mainly divided into: simple spring embolism treatment, balloon auxiliary spring ring treatment, stent auxiliary spring ring treatment and blood flow guiding device treatment.

Wherein stent-assisted coil therapy is the current mainstream of aneurysm treatment in clinic. Embolic auxiliary stents are of two general categories, cutting stents and braided stents. The metal coverage rate of the cutting stent is low, the damage to blood vessels is small, the thrombus formation after operation is small, and the complications are small; the braided stent is recoverable after being partially released, the metal coverage rate is high, the adherence of the stent in a bent blood vessel is good, meshes are adjustable, the distribution of stent wires can be adjusted after the aneurysm coil is stuffed, and the support of the stent to the coil is enhanced. But the metal coverage is too high, and the crossing points among the braided wires are easy to cause thrombosis to cause vascular embolism, and postoperative complications are high.

The main problems of the current auxiliary embolism stent in the market are that 1, the cut stent meshes are mainly divided into two types, namely a closed loop design and an open mesh design, and the closed loop design has the advantages that the stent is partially released and recycled, and the stent with the open loop design is partially released and cannot be recycled; the open loop design has the advantages of good adherence, good bending resistance, difficult displacement of the stent, and the closed loop design has the advantages that the adherence, bending resistance and displacement resistance of the stent are improved through special mesh design, and the two performances are still inferior in the closed loop design as a whole. 2. The development points of the cutting stent are basically arranged at two ends of the stent, the middle of the stent is undeveloped, and the development of the middle of the stent is unclear due to poor development of the NiTi material, especially in the case of a thin rod width, so that the actual condition of the stent in a blood vessel cannot be observed, for example: the stent collapses, folds, has poor adherence and the like in a curved vessel, so that the stent cannot be timely adjusted. The stent is collapsed, folded and attached incompletely in the blood vessel, and thrombus and even vascular occlusion can be caused after operation.

Disclosure of Invention

In view of the above problems, the invention provides an auxiliary stent for intracranial aneurysm embolism, comprising a stent main body, wherein the stent main body is provided with a hollow cylindrical structure, the side wall of the cylindrical structure of the stent main body is provided with a net structure, the distal end part of the stent main body is provided with a closed-loop stent (the minimum cell is a closed polygon), and the proximal end part of the stent main body is provided with an open-loop stent (the minimum cell is a combination of n polygons, n is more than or equal to 2, and the number of sides of the polygons is more than or equal to 3); the axial length of the closed loop bracket part accounts for 1/2-2/3 of the axial length of the bracket main body.

As a preferable technical scheme, the distal end of the bracket main body is fixedly connected and provided with a first extension part, the first extension part is in a horn shape, and the diameter of the first extension part gradually increases from the distal end of the bracket to the distal end direction; the maximum diameter of the first extension part is 1.2-1.8 times of the diameter of the bracket main body; the inclination angle of the side wall of the first extension part relative to the axial direction of the bracket main body is set to be 15-45 degrees.

As a preferable technical scheme, the proximal end of the bracket main body is fixedly connected and provided with a second extension part, the second extension part is straight, and the diameter of each part of the second extension part is the same as the diameter of the bracket main body.

As a preferable technical scheme, the proximal end fixed connection of the support main body is provided with a second extension portion, the second extension portion is arranged in a horn shape, and the diameter of the second extension portion gradually increases from the proximal end of the support to the proximal end.

As a preferable technical scheme, the bracket main body is fixedly provided with a plurality of developing points, and the developing points are fixedly arranged on the branches of the bracket main body reticular structure; the developing points are uniformly distributed or dispersedly distributed in the axial direction of the bracket main body; the developing points are uniformly distributed or dispersedly distributed in the circumferential direction of the bracket main body.

As a preferable technical scheme, the first extension part and the second extension part are fixedly provided with a plurality of developing points; the developing points are fixedly connected to the branches of the net structure in the modes of embedding, wire winding, welding, pressing holding, bonding and the like, or alternatively, the developing points are reserved on the cutting sites.

The conveying system based on the intracranial aneurysm embolism auxiliary bracket comprises a guide wire, wherein the distal end part of the guide wire is provided with a pressing and holding section, the pressing and holding section is provided with a boss structure, and the part with the boss structure on the pressing and holding section and the part without the developing point of the bracket main body are correspondingly arranged on the axial position; the part of the pressing and holding section without the boss structure is arranged corresponding to the part of the support main body with the developing point in the axial position.

As a preferable technical scheme, the axial length of the bracket main body after being pressed is equal to the length of the pressing section.

As a preferred technical solution, the distal end of the pressing and holding section is provided with a distal protrusion, and the distal protrusion is made of a developable material.

As a preferable technical scheme, the medical device further comprises an introducing sheath, wherein the distal end of the introducing sheath is in a necking structure, the material of the introducing sheath is a polymer pipe, a plurality of holes are formed in the side wall of the distal end of the introducing sheath, and the diameter of each hole is 3/4-4/5 of the diameter of the introducing sheath.

The beneficial effects are that:

(1) In the stent implantation operation process, because the axial length of the pressed stent can be changed in the release process, as the far-end developing point for judging the position of the stent by a doctor, the far-end developing point can axially move in the release process and the position changes, so that the doctor cannot accurately release the stent at the target position. The closed loop design has the advantages that the stent is partially released and recoverable, and the stent with the open loop design is partially released and can not be recovered; the open loop design has the advantages of good stent adherence, good bending resistance and difficult stent displacement, the stent body is provided with a closed loop stent at the distal end part of the stent body, the open loop stent is provided at the proximal end part, and in some preferred embodiments, the stent is still completely recyclable when the stent is 2/3 of the length before being released, and the stent cannot be recycled until 1/3 of the stent is released. The recyclable design allows a doctor to repeatedly release and recycle the stent when placing the stent, ensures that the final placement position of the stent is completely accurate, and meets the operation requirements. Through the setting of open-loop support and closed-loop support's combination, the support can be enough partial release recoverable, can have better adherence nature again, anti bending nature, prevents the performance of shifting.

(2) The invention also provides an intermediate delivery guidewire for crimping and delivering an intermediate or multi-stage developed stent. The distal end of the conveying guide wire is provided with a section which is specially designed for a pressing and holding bracket, the pressing and holding section is mainly designed as a continuous or interval boss, and the diameter of the boss can be equal, unequal and continuous variable; the boss can be made of stainless steel, platinum iridium alloy, platinum tungsten alloy, silica gel, high molecular polymer, UV glue and the like; the boss can be formed by grinding a guide wire mandrel, welding or bonding a winding spring on the guide wire, welding or bonding a metal, alloy or polymer pipe on the guide wire, and directly photocuring by UV glue dispensing.

(3) In addition to the stent crimping segment, the distal end of the delivery guidewire is also divided into 2 types, namely, a distal end protrusion and a non-distal end protrusion, wherein the distal end of the guidewire with the distal end protrusion is provided with a long and thin developable distal end protrusion on the distal side of the stent crimping segment, and the distal end of the guidewire without the distal end protrusion is the top end of the guidewire (the length of the stent after crimping is equal to the top end of the guidewire) on the distal side of the stent crimping segment, and no other structure or deployment exists. The guide wire with the distal end is suitable for relatively straight blood vessels at the position of the aneurysm, and the guide wire without the distal end is suitable for relatively tortuous blood vessels at the position of the aneurysm. The leading-in sheath is a polymer pipe with a far-end necking, and the material is PTFE, PFA, HDPE, PA. The distal side of the leading-in sheath is provided with two holes, the diameter of each hole is about 4/5 of the diameter of the tube, and the side holes are used for conveniently discharging bubbles and injecting heparin physiological saline when the stent is clinically used.

Drawings

FIG. 1 is a schematic diagram of the structure of an intracranial aneurysm embolization stent provided in an embodiment of the present invention;

FIG. 2 is a schematic diagram of the structure of an intracranial aneurysm embolization stent provided in an embodiment of the present invention;

FIG. 3 is a schematic view of the structure of a guidewire of a delivery system provided in an embodiment of the present invention;

FIG. 4 is a schematic view of the structure of a guidewire of a delivery system provided in an embodiment of the present invention;

FIG. 5 is a schematic view of the structure of an introducer sheath of a delivery system according to an embodiment of the present invention;

FIG. 6 is a schematic view of the combined mounting structure of an intracranial aneurysm embolization auxiliary stent and a delivery system provided in the present invention;

the device comprises a 1-bracket main body, a 11-closed-loop bracket, a 12-open-loop bracket, a 13-first extension part, a 14-second extension part, a 15-development point, a 2-guide wire, a 21-press holding section, a 22-boss structure, a 23-distal protrusion, a 3-guide sheath and a 31-hole.

Detailed Description

An auxiliary stent for intracranial aneurysm embolism, shown in fig. 1 and 2, comprising a stentmain body 1, wherein the stentmain body 1 is provided with a hollow cylindrical structure, the side wall of the cylindrical structure of the stentmain body 1 is provided with a net structure, the distal end part of the stentmain body 1 is provided with a closed-loop stent 11, and the proximal end part of the stentmain body 1 is provided with an open-loop stent 12; the axial length of the closedloop bracket 11 part accounts for 1/2-2/3 of the axial length of the bracketmain body 1.

Preferably, the axial length of the closedloop stent 11 portion is 2/3 of the axial length of thestent body 1.

Preferably, the bracket main body is made of NiTi pipe through cutting.

The closed loop bracket, namely the minimum grid unit of the net structure of the bracket main body, is a closed graph; the open-loop bracket is characterized in that the minimum grid units of the net structure of the bracket main body are non-closed patterns, and at least three minimum grid units are combined to form a closed pattern in the open-loop bracket.

In the stent implantation operation process, because the axial length of the pressed stent can be changed in the release process, as the far-end developing point for judging the position of the stent by a doctor, the far-end developing point can axially move in the release process and the position changes, so that the doctor cannot accurately release the stent at the target position.

The closed loop design has the advantages that the stent is partially released and recoverable, and the stent with the open loop design is partially released and can not be recovered; the open loop design has the advantages of good stent adherence, good bending resistance and difficult stent displacement, the stent body is provided with a closed loop stent at the distal end part of the stent body, the open loop stent is provided at the proximal end part, and in some preferred embodiments, the stent is still completely recyclable when the stent is 2/3 of the length before being released, and the stent cannot be recycled until 1/3 of the stent is released. The recyclable design allows a doctor to repeatedly release and recycle the stent when placing the stent, ensures that the final placement position of the stent is completely accurate, and meets the operation requirements. Through the setting of open-loop support and closed-loop support's combination, the support can be enough partial release recoverable, can have better adherence nature again, anti bending nature, prevents the performance of shifting.

The distal end of the bracketmain body 1 is fixedly connected and provided with afirst extension part 13, thefirst extension part 13 is in a horn shape, and the diameter of thefirst extension part 13 gradually increases from the distal end of the bracket to the distal end direction; the maximum diameter of thefirst extension part 13 is 1.2-1.8 times of the diameter of the bracketmain body 1; the inclination angle of the side wall of thefirst extension part 13 with respect to the axial direction of the bracketmain body 1 is set to 15-45 degrees. By providing the first extension, the adherence of the closed loop cut portion of the stent is improved and displacement is prevented.

Preferably, the cutting pattern of the stent body is of a "wave" design in the radial direction to improve the adherence of the closed loop cut portion of the stent and to prevent displacement.

The proximal end of the bracketmain body 1 is fixedly connected and provided with asecond extension part 14, thesecond extension part 14 is straight, and the diameter of each part of thesecond extension part 14 is the same as the diameter of the bracketmain body 1.

The proximal end of the bracketmain body 1 is fixedly connected with asecond extension part 14, thesecond extension part 14 is in a horn shape, and the diameter of thesecond extension part 14 gradually increases from the proximal end of the bracket to the proximal end.

A plurality of developingpoints 15 are fixedly arranged on the bracketmain body 1, and the developingpoints 15 are fixedly arranged on branches of the net-shaped structure of the bracketmain body 1; the developingpoints 15 are uniformly distributed or dispersedly distributed in the axial direction of the bracketmain body 1; the plurality of developingpoints 15 are uniformly or dispersedly distributed in the circumferential direction of the holdermain body 1.

The developing points are uniformly or dispersedly distributed in the axial direction of the support, and can be uniformly or dispersedly distributed in the radial direction, and the support can be subjected to multi-stage development or sectional development. The stent with intermediate visualization or multi-section visualization has the advantages that the relative position of the stent and the aneurysm, the deployment condition of the stent after being released in a blood vessel, the combination of radiography, the adhesion condition of the stent and the like can be clearly positioned. When poor stent adhesion or poor placement relative to the aneurysm is observed, the stent can be retrieved, repositioned and released again to obtain a better stent morphology.

A plurality of developingpoints 15 are fixedly arranged on thefirst extension part 13 and thesecond extension part 14; the developingpoints 15 are fixedly connected to the branches of the net structure through embedding, wire winding, welding, pressing and holding, bonding and the like, or alternatively, the developingpoints 15 are reserved on the cutting sites.

As shown in fig. 3, a delivery system based on the intracranial aneurysm embolism auxiliary stent of any one of the above, comprises aguide wire 2, wherein a distal end part of theguide wire 2 is provided with apress holding section 21, thepress holding section 21 is provided with aboss structure 22, and a part with theboss structure 22 on thepress holding section 21 is correspondingly arranged on an axial position with a part without the developingpoint 15 of the stentmain body 1; the part of the press-holding section 21 without theboss structure 22 is arranged at an axial position corresponding to the part of the holdermain body 1 with the developingpoint 15.

The diameter of the boss can be equal or unequal, or can be continuously variable;

the boss can be made of stainless steel, platinum iridium alloy, platinum tungsten alloy, silica gel, high molecular polymer, UV glue, platinum, gold, niTi alloy and the like;

the boss can be formed by grinding a guide wire mandrel, welding or bonding a winding spring on the guide wire, welding or bonding a metal, alloy or polymer pipe on the guide wire, and directly photocuring by UV glue dispensing.

The boss is used to cooperate with the wall of the leading-in sheath or the micro-catheter, hold the stent by pressure, clamp the developing point of the stent between two adjacent bosses, when the stent is retracted, the clamp main does not release the developing point of the catheter yet, and provide the retracting pulling force to pull the stent back into the sheath.

Preferably, the material of the boss is a material having developability, for example: platinum iridium alloy, platinum tungsten alloy, platinum, gold, etc., or a polymer material comprising tungsten powder, tantalum powder.

The boss has the advantage of developing the guide wire in a plurality of sections, has good marking and pointing effects in blood vessels, and can well position the relative position between the bracket and the guide wire and determine the release degree of the bracket.

The axial length of the bracketmain body 1 after being pressed is equal to the length of thepressing section 21.

As shown in fig. 4, the distal end of thepress grip section 21 is provided with adistal protrusion 23, and thedistal protrusion 23 is made of a developable material.

As shown in fig. 5, the medical device further comprises an introducingsheath 3, wherein the distal end of the introducingsheath 3 is provided with a necking structure, the material of the introducingsheath 3 is provided with a polymer pipe, the side wall of the distal end of the introducingsheath 3 is provided with a plurality ofholes 31, and the diameter of theholes 31 is 3/4-4/5 of the diameter of the introducingsheath 3.

The leading-in sheath is a polymer pipe with a far-end necking, and the material is PTFE, PFA, HDPE, PA. The distal side of the leading-in sheath is provided with two holes, the diameter of each hole is preferably 4/5 of the diameter of the tube, and the side holes are used for conveniently discharging bubbles and injecting heparin physiological saline when the stent is clinically used.

Working principle: this patent proposes a embolism auxiliary stand of multistage development, and part release is recoverable, has adherence nature simultaneously, anti bending nature and anti-displacement nature concurrently. And a delivery guidewire and an introducer sheath for delivery and release in cooperation with the multi-segment development stent. The NiTi tube of the bracket is cut, the far end is closed, the near end is open, the far end is flared, the near end is straight, developing points are arranged at two ends of the bracket, and meanwhile, developing points are also arranged in the middle of the bracket and are uniformly or dispersedly distributed in the axial direction and the radial direction. The distal support pressing section of the conveying guide wire is provided with a plurality of spaced bosses, the length and the interval of the bosses are matched with the positions of the development points after the support pressing, the guide wire at the position with the development points after the support pressing is provided with no boss, and the guide wire at the position without the development points is provided with a boss. The conveying guide wire has two designs of a head end and a no head end, and is respectively suitable for straight and tortuous blood vessels at the far end. The side of the leading-in sheath is provided with a hole, so that air bubbles can be conveniently discharged and heparin physiological saline can be conveniently injected. The support multistage development can observe the opening condition of support in the release process, if found that the support opens poorly, but the back adjustment position release again. In addition, the stent with the complete open-loop design is not recyclable after being partially released, so that the stent with the closed-loop and open-loop designs ensures the direct partial release and recycling performance. In addition, the design of the distal horn mouth of the stent and the design of the proximal open loop of the stent both increase the stability of the stent in the blood vessel and prevent the stent from shifting in the pulsation of the blood vessel. The design of the interval boss ensures that the bracket can be pressed into the conveying guide wire and the guide sheath, does not increase the pushing resistance of the bracket, is convenient for the recovery of the bracket after the release of the bracket part, and provides pulling force.

Claims (7)

1. An intracranial aneurysm embolism auxiliary bracket is characterized by comprising a bracket main body (1), wherein the bracket main body (1) is of a hollow cylindrical structure, the side wall of the cylindrical structure of the bracket main body (1) is of a net structure, the distal end part of the bracket main body (1) is of a closed-loop bracket (11), and the proximal end part of the bracket main body (1) is of an open-loop bracket (12);

the axial length of the closed-loop bracket (11) accounts for 2/3 of the axial length of the bracket main body (1);

the distal end of the bracket main body (1) is fixedly connected and provided with a first extension part (13), the first extension part (13) is in a horn shape, and the diameter of the first extension part (13) gradually increases from the distal end of the bracket main body to the distal end direction;

the maximum diameter of the first extension part (13) is 1.2-1.8 times of the diameter of the bracket main body (1); the inclination angle of the side wall of the first extension part (13) relative to the axial direction of the bracket main body (1) is set to be 15-45 degrees;

the proximal end fixed connection of support main part (1) is provided with second extension (14), second extension (14) are set up to straight form or loudspeaker form, everywhere diameter of second extension (14) with support main part (1) diameter is the same or follow the proximal end of support main part is the diameter grow gradually to the proximal end direction diameter.

2. The auxiliary intracranial aneurysm embolism bracket according to claim 1, wherein a plurality of developing points (15) are fixedly arranged on the bracket main body (1), and the developing points (15) are fixedly arranged on branches of the net structure of the bracket main body (1); the developing points (15) are uniformly distributed or dispersedly distributed in the axial direction of the bracket main body (1).

3. Intracranial aneurysm embolization auxiliary stent according to claim 1, wherein the first extension (13) and the second extension (14) are fixedly provided with a plurality of visualization points (15); the developing points (15) are fixedly connected to the branches of the net structure in a manner of embedding, wire winding, welding, pressing holding or bonding, or alternatively, the developing points (15) are reserved on the cutting sites.

4. A delivery system based on an auxiliary intracranial aneurysm embolism bracket as claimed in any one of claims 1-3, and characterized by comprising a guide wire (2), wherein a distal end part of the guide wire (2) is provided with a pressing and holding section (21), the pressing and holding section (21) is provided with a boss structure (22), and a part with the boss structure (22) on the pressing and holding section (21) and a part without the developing point (15) of the bracket main body (1) are correspondingly arranged on an axial position; the part of the press holding section (21) without the boss structure (22) is arranged corresponding to the part of the support main body (1) with the developing point (15) in the axial position.

5. The delivery system according to claim 4, characterized in that the axial length of the stent body (1) after crimping is equal to the length of the crimping section (21).

6. A delivery system according to claim 5, characterized in that the press grip section (21) is distally provided with a distal protrusion (23), the distal protrusion (23) being made of a developable material.

7. The delivery system according to claim 4, further comprising an introducer sheath (3), the distal end of the introducer sheath (3) being provided in a reduced configuration, the material of the introducer sheath (3) being provided as a polymeric tubing, the distal side wall of the introducer sheath (3) being provided with a number of holes (31), the diameter of the holes (31) being set to 3/4-4/5 of the diameter of the introducer sheath (3).

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