Peripheral vessel embolism device

Abstract

The invention relates to the technical field of medical instruments, in particular to a peripheral vessel embolism device which comprises a spring ring assembly, a push rod assembly and a protective sheath tube. The spring ring assembly comprises a polymer spring, a ball and a connecting arm which are connected to the two ends of the polymer spring respectively, and nickel-titanium wires which are arranged at the two ends in the polymer spring and connected with the ball and the connecting arm respectively. The pushing rod assembly comprises a pushing rod pipe body, a releasing wire arranged in the pushing rod pipe body and a near-end plug arranged at the near end of the releasing wire in a sleeving mode. Wherein the far end of the releasing wire is connected with the near end of the connecting arm, a fragile point is formed at the connecting position of the releasing wire, and the fragile point can be broken under the action of external force to achieve falling of the spring ring assembly. By means of the arrangement, the arrangement cost and the machining difficulty are reduced, releasing of the spring ring assembly is controllable through the arrangement of the fragile points, and pushing and releasing are easier.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a peripheral vascular embolization device. Background Art

[0002] The embolization device in peripheral vascular interventional treatment is a type of medical device specifically used to block or reduce blood flow, and is usually used to treat various lesions in peripheral blood vessels. Among them, the most commonly used in interventional surgery is the spring coil, which, after entering the target blood vessel, stays in a blood vessel of similar diameter to form a mechanical embolism. Thrombus can usually form around the embolus and at the distal end of the embolic blood vessel, resulting in local blood flow interruption.

[0003] In the prior art, a Chinese utility model patent with authorization announcement number CN220256503U disclosed a medical embolization device on December 29, 2023, whose embolization unit includes a shape memory alloy skeleton, an embolization promoting element and a developing element. The shape memory alloy skeleton includes a linear shape or an embolization shape. The embolization promoting element is arranged on the surface of the shape memory alloy skeleton or surrounds the shape memory alloy skeleton. The developing element is arranged inside the shape memory alloy skeleton or surrounds the shape memory alloy skeleton. The shape of the embolization device is adjusted by temperature, and a linear shape is used to reduce resistance during delivery.

[0004] However, the existing spring coils are usually made of platinum-tungsten alloy, which is heat-treated to achieve shape memory and is ultimately made into embolic spring coils. However, such materials and processing techniques result in high costs for the spring coils. Secondly, the connection between the existing spring coils and the push rods often causes the spring coils to fall off naturally after the push rods are pushed out of the delivery catheter, making it impossible to achieve controlled release. Summary of the invention

[0005] In view of at least one of the above technical problems, the present invention provides a peripheral vascular embolization device, which adopts improvements in structure and materials to reduce costs and achieve controllable release of the spring coil connection points.

[0006] According to a first aspect of the present invention, there is provided a peripheral vascular embolization device, comprising a coil assembly, a push rod assembly and a protective sheath;

[0007] The spring coil assembly comprises a polymer spring, a ball and a connecting arm respectively connected to the two ends of the polymer spring, and a nickel-titanium wire arranged at the two ends inside the polymer spring and connected to the ball and the connecting arm respectively;

[0008] The push rod assembly comprises a push rod tube body, a release wire arranged inside the push rod tube body, and a proximal plug sleeved on the proximal end of the release wire;

[0009] The distal end of the release wire is connected to the proximal end of the connecting arm, and the release wire forms a fragile point at the connection, which can be broken under the action of external force to achieve the shedding of the spring coil assembly.

[0010] In some embodiments of the present invention, the release wire is ground into a thin segment having a smaller diameter than the remaining portion at the connection with the connecting arm, and the thin segment breaks under the action of axial tension or after being electrified.

[0011] In some embodiments of the present invention, the polymer spring is in the shape of a spring and is made of PP, PET or degradable PLGA.

[0012] In some embodiments of the present invention, platinum-iridium developer powder is added to the material of the polymer spring.

[0013] In some embodiments of the present invention, the sphere is made of the same material as the polymer spring, the sphere is processed into a spherical shape by melting or extrusion, and the proximal end of the sphere has a connecting end that is sleeved on the end of the polymer spring, the connecting end is hollow, and the hollow part is used for the insertion of the distal end of the nickel-titanium wire.

[0014] In some embodiments of the present invention, the connecting arm is made of the same material as the polymer spring, the distal end of the connecting arm has a sleeve portion for inserting the polymer spring, the proximal end of the connecting arm also has a connecting hole for the release wire to pass through, and the inside of the sleeve portion also has a through hole for the proximal end of the nickel-titanium wire to pass through.

[0015] In some embodiments of the present invention, the push rod tube body is a tubular structure, the distal end is spirally cut to form a spring segment, and the proximal end is cut into grooves, and the grooves are distributed in a ring shape or a dot shape.

[0016] In some embodiments of the present invention, the release wire is folded inside the push rod tube body, and the distal end folds back after passing through the perforation. The proximal plug has two through holes adapted to the release wire. The proximal plug is inserted into the push rod tube body and is located in the proximal end of the groove.

[0017] In some embodiments of the present invention, the protective sheath is made of PE material, and one end is processed into a cone shape, and the connection point between the spring coil assembly and the push rod assembly is located inside the protective sheath.

[0018] In some embodiments of the present invention, the nickel-titanium wire is made of shape memory nickel-titanium alloy, and the nickel-titanium wire can be shaped into a three-dimensional shape after heat treatment.

[0019] The beneficial effects of the present invention are as follows: the present invention sets the polymer spring in the spring coil assembly as a polymer material, and forms a fragile point structure at the connection between the release wire and the connecting arm. Compared with the prior art, on the one hand, the setting cost and processing difficulty are reduced, and on the other hand, through the setting of the fragile point, the release of the spring coil assembly is controllable, making pushing and release easier. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 Schematic diagram of the structure of a peripheral vascular embolization device in an embodiment of the present invention;

[0022] Figure 2 It is a structural schematic diagram of a spring coil assembly in an embodiment of the present invention;

[0023] Figure 3 It is a structural schematic diagram of a push rod assembly in an embodiment of the present invention;

[0024] Figure 4 Schematic diagram of the connection structure between the connecting arm and the release wire in an embodiment of the present invention;

[0025] Figure 5 It is a schematic diagram of the electrolytic release structure of the connecting arm and the release wire in an embodiment of the present invention;

[0026] Figure 6 It is a schematic structural diagram of the external force release of the connecting arm and the release wire in an embodiment of the present invention;

[0027] Figure 7 This is a schematic diagram of the structure of a sphere in an embodiment of the present invention;

[0028] Figure 8 This is a schematic structural diagram of a connecting arm in an embodiment of the present invention;

[0029] Fig. 9 It is a structural schematic diagram of a push rod tube body in an embodiment of the present invention;

[0030] Fig.10 It is a schematic diagram of the structure of the release wire in an embodiment of the present invention;

[0031] Fig.11 Schematic diagram of the structure of the proximal plug in an embodiment of the present invention;

[0032] Fig.12This is a schematic diagram of the structure of the protective sheath tube in an embodiment of the present invention;

[0033] Fig.13 Schematic diagram of the three-dimensional structure of the nickel-titanium wire in an embodiment of the present invention.

[0034] Explanation of the reference numerals: a, spring coil assembly; b, push rod assembly; c, protective sheath; 1, ball; 2, nickel-titanium wire; 3, polymer spring; 4, connecting arm; 5, push rod body; 6, release wire; 7, proximal plug. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0036] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0038] like Figures 1 to 13 The peripheral vascular embolization device shown in the figure comprises a coil assembly a, a push rod assembly b and a protective sheath c; Figure 1 As shown in, in an embodiment of the present invention, the proximal end of the spring coil assembly a is connected to the distal end of the push rod assembly b, and the entire spring coil assembly a and the distal end of the push rod assembly b are both sleeved in a protective sheath c for protection; it should be pointed out here that, in an embodiment of the present invention, the proximal end refers to the end close to the operator, and the distal end refers to the end away from the operator.

[0039] Please refer to Figure 2In an embodiment of the present invention, the spring coil assembly a comprises a polymer spring 3, a ball 1 and a connecting arm 4 respectively connected to the two ends of the polymer spring 3, and a nickel-titanium wire 2 arranged at the two ends inside the polymer spring 3 and connected to the ball 1 and the connecting arm 4 respectively; the connection here is a detachable connection, that is, the two ends of the nickel-titanium wire 2 are respectively inserted into the ball 1 and the connecting arm 4. In an embodiment of the present invention, the nickel-titanium wire 2 is in a state as follows before being released. Figure 2 In the straight state shown in FIG. , after the coil assembly a reaches the target position and is released from the microcatheter, the coil assembly a is exposed to the normal temperature in the body, and the nickel-titanium wire 2 quickly restores its preset shape, which can be as follows: Fig.13 The spherical structure shown in , or it can also be a two-dimensional spiral shape.

[0040] like Figure 3 As shown in, in an embodiment of the present invention, the push rod assembly b includes a push rod tube body 5, a release wire 6 arranged inside the push rod tube body 5, and a proximal plug sleeved on the proximal end of the release wire 6; the release wire 6 and the proximal plug can move inside the push rod tube body 5 to achieve the pushing of the spring coil and the release of the release wire 6.

[0041] like Figure 4 As shown in , the distal end of the release wire 6 is connected to the proximal end of the connecting arm 4, and the release wire 6 forms a fragile point at the connection, which can be broken under the action of external force to achieve the detachment of the spring coil assembly a. It should be pointed out here that in some embodiments of the present invention, the external force can be an axially applied tensile force, or it can also be the energy generated after power is turned on, etc. Through the setting of this structural form, not only the release is controllable, but also the cost of the spring coil can be reduced.

[0042] In the above embodiment, by setting the polymer spring 3 in the spring coil component a to a polymer material, and forming a fragile point structure at the connection between the release wire 6 and the connecting arm 4, compared with the prior art, on the one hand, the setting cost and processing difficulty are reduced, and on the other hand, through the setting of the fragile point, the release of the spring coil component a is controllable, making pushing and release easier.

[0043] Based on the above embodiments, Fig.10 As shown in the figure, the release wire 6 is ground into a thin section with a diameter smaller than the rest of the section at the connection with the connecting arm 4, that is, the diameter of the release wire 6 is processed to be thinner at the distal end to facilitate release; please refer to the specific release method Figure 5 , the thin section breaks after power is applied, similar to a fuse, which will be blown out when the current is large, so that when the two ends of the release wire 6 are connected to positive and negative poles respectively, release can be achieved; in addition, if Figure 6As shown in , in another embodiment of the present invention, the thin segment of the release wire 6 can be broken by applying an axial pulling force toward the proximal end to achieve the release of the spring coil assembly a.

[0044] In an embodiment of the present invention, the polymer spring 3 is in the form of a spring and is made of PP, PET or degradable PLGA. In addition, in order to achieve the purpose of developing during surgery, platinum-iridium developing powder is added to the material of the polymer spring 3. By adding platinum-iridium developing powder, the radiopaque nature of the polymer spring 3 can be achieved, thereby facilitating observation during surgery. In an embodiment of the present invention, PP is made of polypropylene, which has good flexibility and durability and can resist long-term mechanical fatigue; PET is made of polyethylene terephthalate, which has high mechanical strength and good fatigue resistance and is suitable for implants that need to maintain their shape and function for a long time. PLGA is a polylactic acid-glycolic acid copolymer. Although this material has slightly worse mechanical properties than PP and PET, it can be designed to gradually disintegrate within a set time, which is suitable for certain short-term implant applications.

[0045] Alternatively, if Figure 7 As shown in the figure, it is a schematic diagram of the structure of the ball 1 in the embodiment of the present invention. The ball 1 is made of the same material as the polymer spring 3. The ball 1 is spherical by melting or extrusion, and the proximal end of the ball 1 has a connecting end sleeved on the end of the polymer spring 3. The connecting end is hollow, and the hollow part is used for inserting the distal end of the nickel-titanium wire 2. Please refer to Figure 2 When the ball 1 is connected to the polymer spring 3, the connecting end is embedded in the polymer spring 3, and the distal end of the nickel-titanium wire 2 is inserted into the hollow part of the ball 1. The arrangement of the ball 1 is conducive to the smooth movement of the spring coil assembly a in the blood vessel, reduces the resistance to movement, and avoids damage to the blood vessel wall.

[0046] In some embodiments of the present invention, Figure 8 As shown in , the connecting arm 4 is made of the same material as the polymer spring 3, the distal end of the connecting arm 4 has a sleeve portion for inserting the polymer spring 3, the proximal end of the connecting arm 4 also has a connecting hole for the release wire 6 to pass through, and the sleeve portion also has a perforation for the proximal end of the nickel-titanium wire 2 to pass through. In addition, it should be pointed out here that in the embodiment of the present invention, the connection between the ball 1 and the connecting arm 4 and the polymer spring 3 can be connected by clamping, or by bonding or welding. And the setting of the hollow part of the ball 1 and the perforation of the connecting arm 4 is conducive to maintaining the shape of the nickel-titanium wire 2 before release, thereby improving the accuracy of release.

[0047] like Fig. 9As shown in the figure, the push rod body 5 is a tubular structure, the distal end is cut into a spring segment by spiral cutting, and the proximal end is cut into a groove, and the groove is distributed in a ring or point shape. The cutting here can be performed by spiral cutting with a laser. In the embodiment of the present invention, the push rod body 5 is set to be made of stainless steel. By setting its distal end as a spring segment structure, the stainless steel rod body can be made soft and easy to adapt to various tortuous blood vessel shapes. By cutting the groove structure at the proximal end, the groove can be broken.

[0048] Please refer to Fig.10 and Fig.11 In an embodiment of the present invention, the release wire 6 is folded in the push rod tube body 5, and the distal end passes through the perforation and then folds back. The proximal plug has two through holes adapted to the release wire 6. The proximal plug is inserted into the push rod tube body 5 and is located in the proximal end of the groove. With the arrangement of this structural form, the two through holes can pass through the release wire 6. During the specific operation, the release wire 6 first passes through the perforation of the connecting arm 4, so that the thin section of the release wire 6 is located at the position of the hole of the connecting arm 4. The connecting arm 4 is partially inserted into the push rod tube body 5. The release wire 6 is fixed and tightened by the proximal plug. The proximal plug is inserted into the push rod tube body 5, and a compressive grip is applied to the stainless steel tube to fix the push rod tube body 5, the release wire 6 and the proximal plug together. Figure 6 As shown in , when releasing, it is only necessary to apply force to the groove of the push rod tube 5 to partially break the push rod tube 5, and then apply pulling force toward the proximal end to disengage the release wire 6 from the connecting arm 4, thereby achieving separation of the spring coil assembly a.

[0049] In an embodiment of the present invention, the protective sheath c is made of PE material, and one end is processed into a cone, and the connection point between the spring coil component a and the push rod component b is inside the protective sheath c. PE is a polyethylene material, which has good biocompatibility and can withstand certain bending and stretching. The cone setting facilitates the introduction of the spring coil component a. In addition, in an embodiment of the present invention, the nickel-titanium wire 2 is made of a shape memory nickel-titanium alloy, and the nickel-titanium wire 2 can be shaped into a three-dimensional shape after heat treatment. The three-dimensional shape here can be as follows: Fig.13 The spherical shape shown in the figure may also be other various shapes that meet clinical needs.

[0050] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A peripheral vascular embolization device, characterized in that: It includes a spring coil assembly, a push rod assembly and a protective sheath; The spring coil assembly comprises a polymer spring, a ball and a connecting arm respectively connected to the two ends of the polymer spring, and a nickel-titanium wire arranged at the two ends inside the polymer spring and connected to the ball and the connecting arm respectively; The push rod assembly comprises a push rod tube body, a release wire arranged inside the push rod tube body, and a proximal plug sleeved on the proximal end of the release wire; The distal end of the release wire is connected to the proximal end of the connecting arm, and the release wire forms a fragile point at the connection, which can be broken under the action of external force to achieve the shedding of the spring coil assembly.

2. The peripheral vascular embolization device according to claim 1, characterized in that: The release wire is ground into a thin section with a diameter smaller than the remaining part at the connection point with the connection arm, and the thin section breaks under the action of axial tension or after being electrified.

3. The peripheral vascular embolization device according to claim 1, characterized in that: The polymer spring is in the shape of a spring and is made of PP, PET or degradable PLGA.

4. The peripheral vascular embolization device according to claim 3, characterized in that: Platinum-iridium developing powder is added to the material of the polymer spring.

5. The peripheral vascular embolization device according to claim 3, characterized in that: The sphere is made of the same material as the polymer spring. The sphere is shaped into a sphere by melting or extrusion. The proximal end of the sphere has a connecting end sleeved on the end of the polymer spring. The connecting end is hollow, and the hollow part is used for inserting the distal end of the nickel-titanium wire.

6. The peripheral vascular embolization device according to claim 3, characterized in that: The connecting arm is made of the same material as the polymer spring. The distal end of the connecting arm has a sleeve portion for inserting the polymer spring. The proximal end of the connecting arm also has a connecting hole for the release wire to pass through. The sleeve portion also has a through hole for the proximal end of the nickel-titanium wire to pass through.

7. The peripheral vascular embolization device according to claim 6, characterized in that: The push rod tube body is a tubular structure, the distal end is spirally cut to form a spring segment, and the proximal end is cut into grooves, and the grooves are distributed in a ring shape or a dot shape.

8. The peripheral vascular embolization device according to claim 7, characterized in that: The release wire is folded in the push rod tube body, and the distal end folds back after passing through the perforation. The proximal plug has two through holes adapted to the release wire. The proximal plug is inserted into the push rod tube body and is located in the proximal end of the groove.

9. The peripheral vascular embolization device according to claim 1, characterized in that: The protective sheath is made of PE material, and one end is processed into a cone shape. The connection point between the spring coil assembly and the push rod assembly is located inside the protective sheath.

10. The peripheral vascular embolization device according to claim 1, characterized in that: The nickel-titanium wire is made of a shape memory nickel-titanium alloy, and can be shaped into a three-dimensional shape after heat treatment.

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