Vascular stent retriever

Abstract

The present invention discloses a vascular stent retriever, which includes a retrieval tube, a positioning tube that is axially movably inserted into the retrieval tube, and a locking tube that is axially movably inserted into the positioning tube; the front end of the positioning tube extends out through the front end of the retrieval tube, and the front end of the positioning tube is provided with expansion claws; the front end of the locking tube extends out through the front end of the positioning tube, and the front end of the locking tube is provided with a locking cone; when the locking tube moves backward relative to the positioning tube, the locking cone retracts and expands the expansion claws, and when the retrieval tube moves forward relative to the positioning tube and the locking tube, the vascular stent can be received into the front part of the retrieval tube. It has the characteristics of simple structure, convenient use, and can smoothly remove the vascular stent.

Description

Technical Field

[0001] The present invention belongs to the technical field of surgical instruments, and particularly relates to a vascular stent retriever. Background Art

[0002] Cardiovascular disease (CVD) refers to diseases related to the heart or blood vessels. It usually includes coronary heart disease, cerebrovascular disease / stroke, hypertensive heart disease, rheumatic / rheumatoid heart disease, congenital heart disease, aneurysm, myocardial disease, endocarditis, deep vein thrombosis and pulmonary embolism, as well as peripheral arterial vascular diseases. Due to its minimally invasive nature, safety and effectiveness, vascular stent implantation has currently become the main method for treating vascular stenosis. The long-term presence of metal stents in blood vessels still has a negative effect on the endothelial remodeling of the vessel wall and also has a certain impact on the normal contraction and relaxation of blood vessels. Especially when in-stent restenosis occurs, it is difficult to deploy a new stent inside the original metal stent, adding obstacles to secondary treatment. Research shows that when the vascular function is repaired, the vascular stent has no meaning of existence in the body. In addition, a vascular stent is a net-shaped structure made of shape memory metal, usually stored at low temperature. In the low-temperature state, the vascular stent is in a closed and soft state. After being implanted into the human body, it is then expanded with the help of a balloon or the like. During this process, the vascular stent will quickly harden due to the influence of the body temperature. If the vascular stent is not properly positioned before it hardens, the stent needs to be removed and a new one inserted. However, since the vascular stent has already hardened, it is difficult to remove. Therefore, safely and smoothly retrieving the stent outside the body has become a problem to be solved for currently retrievable vascular stents. Summary of the Invention

[0003] In order to overcome the deficiencies of the prior art, the present invention provides a vascular stent retriever that facilitates the safe retrieval of vascular stents.

[0004] To achieve the above object, the technical solution adopted by the present invention is: a vascular stent retriever, comprising a recovery tube, a positioning tube movably inserted along the axis inside the recovery tube, and a locking tube movably inserted along the axis inside the positioning tube; the front end of the positioning tube extends out through the front end of the recovery tube, and the front end of the positioning tube is provided with expansion claws; the front end of the locking tube extends out through the front end of the positioning tube, and the front end of the locking tube is provided with a locking cone; when the locking tube moves backward relative to the positioning tube, the locking cone retracts and expands the expansion claws, and when the recovery tube moves forward relative to the positioning tube and the locking tube, the vascular stent can be received into the front part of the recovery tube.

[0005] Further, it further includes a control handle. The rear end of the positioning tube is connected to the control handle. The control handle is provided with a control button for controlling the axial forward and backward movement of the locking tube relative to the positioning tube, and the control handle is also provided with a pushing seat for controlling the axial forward and backward movement of the recovery tube relative to the positioning tube.

[0006] Furthermore, the control handle is provided with a first guide groove, the first guide groove is arranged along the axial direction of the recovery pipe, the push seat is arranged in the first guide groove and cooperates with the first guide groove in a sliding guide manner, and the push seat is connected to the recovery pipe.

[0007] Furthermore, it also includes a screw rod arranged at the rear end of the locking tube along the axial direction of the locking tube, a guide plate is provided at the front of the screw rod, and a locking nut is threadedly connected to the rear end of the screw rod; a second guide groove is provided on the control handle which is offset from the first guide groove, and the second guide groove is provided along the axial direction of the locking tube and cooperates with the sliding guide of the guide plate. When the locking nut is rotated, the screw rod can drive the locking tube to move forward and backward along the axial direction relative to the positioning tube.

[0008] Furthermore, the control handle is provided with a first positioning groove, and the rear end of the positioning tube is provided with a positioning ring, and the positioning ring is clamped in the first positioning groove and axially limited by the first positioning groove.

[0009] Compared with the prior art, the technical effect achieved by the present invention is as follows: in the initial state of the vascular stent retriever of the present invention, the expansion claw is located outside the front end of the recovery tube, and the locking cone is located outside the front end of the expansion claw. The vascular stent retriever enters the target position of the human body. When the positioning tube is axially extended into the vascular stent, the locking tube is controlled to move backward relative to the positioning tube until the locking cone retreats into the expansion claw and expands the expansion claw. The radial dimension of the expanded expansion claw is larger than the radial dimension of the rear end entrance of the vascular stent. At this time, the expansion claw is tightly connected with the locking cone and clamps the vascular stent, making it unable to move. Then the recovery tube is pushed to collect the vascular stent into the recovery tube. After the vascular stent is collected into the recovery tube, the vascular stent retriever can be taken out and the recovery of the vascular stent is completed. It has the characteristics of simple structure, easy use, and the ability to smoothly remove the vascular stent. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the structure of the vascular stent retriever in an embodiment of the present invention.

[0011] Figure 2 It is a schematic diagram of the structure of the vascular stent retriever in an embodiment of the present invention.

[0012] Figure 3 It is a schematic diagram of the structure of the control handle of the vascular stent retriever in the embodiment of the present invention.

[0013] Figure 4 Schematic diagram of the stent recovery device of the vascular stent in the embodiment of the present invention (the expansion claws are not expanded).

[0014] Figure 5 Schematic diagram of the stent recovery device of the vascular stent in the embodiment of the present invention (the expansion claws are in the expanded state).

[0015] Figure 6 This is a schematic structural view of the push seat base of the vascular stent retriever in the embodiment of the present invention.

[0016] Figure 7 This is a schematic structural view of the upper cover of the push seat of the vascular stent retriever in the embodiment of the present invention.

[0017] The reference numerals in the figure are: 1. vascular stent, 2. guide wire, 3. locking tube, 3-1. locking cone, 3-2. screw, 3-3. guiding piece, 4. positioning tube, 4-1. expansion claw, 4-2. positioning ring, 5. recovery tube, 5-1. recovery tube seat, 6. control handle, 7. first guiding groove, 8. push seat, 8-1 base, 8-2. buckle, 8-2-1. vertical plate portion, 8-2-2. hook portion, 8-3. upper cover, 9. first positioning groove, 10. second positioning groove, 11. locking nut, 12. handle cover, 13. second guiding groove, 14. cover hole. Detailed implementation manners

[0018] The present invention is not limited to the following specific implementation manners. Those of ordinary skill in the art can implement the present invention in other various specific implementation manners according to the content disclosed in the present invention, or any simple changes or modifications made by adopting the design structure and concept of the present invention fall within the protection scope of the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0019] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. can explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0021] Specific embodiments of the present invention are as follows Figures 1 to 5 As shown, a vascular stent retriever includes a retrieval tube 5, a positioning tube 4 movably inserted axially in the retrieval tube 5, and a locking tube 3 movably inserted axially in the positioning tube 4; the front end of the positioning tube 4 extends out through the front end of the retrieval tube 5, and an expansion claw 4-1 is provided at the front end of the positioning tube 4; the front end of the locking tube 3 extends out through the front end of the positioning tube 4, and a locking cone 3-1 is provided at the front end of the locking tube 3; when the locking tube 3 moves backward relative to the positioning tube 4, the locking cone 3-1 retracts and expands the expansion claw 4-1, and when the retrieval tube 5 moves forward relative to the positioning tube 4 and the locking tube 3, the vascular stent 1 can be received into the front part of the retrieval tube 5.

[0022] It further includes a control handle 6. The rear end of the positioning tube 4 is connected to the control handle 6. A control button for controlling the axial forward and backward movement of the locking tube 3 relative to the positioning tube 4 is provided on the control handle 6, and a push seat 8 for controlling the axial forward and backward movement of the retrieval tube 5 relative to the positioning tube 4 is also provided on the control handle 6.

[0023] Specifically, the control handle 6 is provided with a first guide groove 7, which is arranged along the axial direction of the recovery tube 5, and the push seat 8 is arranged in the first guide groove 7 and cooperates with the first guide groove 7 for sliding guidance, and the push seat 8 is connected to the recovery tube 5. More specifically, a second positioning groove 10 is provided in the push seat 8, and a recovery tube seat 5-1 is provided at the rear end of the recovery tube 5, and the recovery tube seat 5-1 is located in the second positioning groove 10. The second positioning groove 10 has an axial limiting effect on the recovery tube seat 5-1, thereby realizing the relative fixation of the recovery tube 5 and the push seat 8. A through hole that passes through the front and rear end surfaces of the recovery tube seat 5-1 is provided in the recovery tube seat 5-1, so that the front end of the positioning tube 4 can be inserted into the recovery tube 5 through the through hole. More specifically, the push seat 8 is composed of a base and an upper cover that is buckled and arranged on the base, and the base and the upper cover are respectively provided with semicircular grooves in sequence, and the two semicircular grooves together form a through hole for the positioning tube 4 to pass through. The second positioning groove 10 is arranged in the semicircular groove on the base 8-1. The two sides of the groove top of the second positioning groove are respectively provided with buckles 8-2 along the axial direction. The buckle 8-2 includes a vertical plate portion 8-2-1 and a hook portion 8-2-2. The vertical plate portion 8-2-1 is formed by extending upward from the groove top of the second positioning groove. The hook portion 8-2-2 is a hook shape formed by bending the top of the vertical plate portion outward. The top of the outer wall on both sides of the semicircular groove on the base 8-1 is provided with a notch along the axial direction. The push seat 8 realizes the sliding guidance with the first guide groove 7 through the notch. A cover hole corresponding to the buckle 8-2 is opened on the upper cover. The cover hole and the buckle 8-2 are buckled together, that is, after the buckle 8-2 is inserted into the cover hole, the hook portion 8-2-2 extends through the cover hole and the hook portion is at the top of the hole wall outside the cover hole.

[0024] It also includes a screw 3-2 arranged at the rear end of the locking tube 3 along the axial direction of the locking tube 3, a guide piece 3-3 is provided at the front of the screw 3-2, and a locking nut 11 used as a control button is threadedly connected to the rear part of the screw 3-2; a second guide groove 13 is also provided on the control handle 6, which is staggered from the first guide groove 7, and the second guide groove 13 is provided along the axial direction of the locking tube 3 and cooperates with the guide piece 3-3 for sliding guidance. When the locking nut 11 is rotated, the screw 3-2 can drive the locking tube 3 to move forward and backward along the axial direction relative to the positioning tube 4.

[0025] The control handle 6 is provided with a first positioning groove 9, and the rear end of the positioning tube 4 is provided with a positioning ring 4-2, which is clamped in the first positioning groove 9 and axially limited by the first positioning groove 9, thereby realizing that the positioning tube 4 is relatively fixedly installed in the control handle 6. More specifically, the rear part of the control handle 6 is provided with a mounting groove, and the first positioning groove 9 is arranged in the mounting groove, and the notch of the mounting groove is buckled with a handle cover 12, which is used for further limiting the positioning tube 4 after installation.

[0026] The working principle of the control handle of this embodiment is as follows: insert the positioning tube 4 described in the present invention into the recovery tube 5, then insert the locking tube 3 into the positioning tube 4, then insert the recovery tube 5 into the handle, put the push seat 8 into the handle 6 and put the recovery tube seat 5-1 into the second positioning groove 10, and then connect and fix the cover hole 14 through the buckle 8-2. Then put the positioning ring 4-1 into the first positioning groove 9, and put the positioning sheet 3-3 fixed on the locking tube 3 into the second guide groove 13. Screw the locking nut 11 into the screw 3-2 and fix it. When the nut 11 is rotated clockwise, the nut 11 will force the screw 3-2 to produce a linear motion along the axial direction, so that the locking tube 3 drives the locking cone 3-1 to move, and the movement of the clamping mechanism of the vascular stent is completed at this time.

[0027] In the initial state of the stent retriever of this embodiment, the expansion claw 4-1 is located outside the front end of the recovery tube 5, and the locking cone 3-1 is located outside the front end of the expansion claw 4-1. The inner hole of the locking tube 3 is used as a guide wire hole, and is used to insert the guide wire 2 for guidance when in use. Specifically, the guide wire 2 is inserted into the stent through the rear end entrance of the stent with the assistance of medical imaging equipment, and then the locking tube 3 on the stent retriever of this embodiment in the initial state is passed through the guide wire 2, and the stent retriever is inserted into the stent 1 with the assistance of the imaging equipment (such as Figure 4 As shown). When the vascular stent 1 is completely inserted into the expansion claw 4-1 on the positioning tube 4, fix the vascular stent retriever. Further, rotate the locking nut 11 clockwise, and the screw 3-2 fixed at the tail of the locking tube 3 will generate axial displacement when it is subjected to the spiral driving force of the locking nut 11, thereby pulling the locking cone 3-1 to move axially until the locking cone 3-1 retreats into the expansion claw 4-1 and expands the expansion claw 4-1. The radial dimension of the expanded claw 4-1 is larger than the radial dimension of the rear end entrance of the vascular stent 1. At this time, the expansion claw 4-1 is tightly connected to the locking cone 3-1 and clamps the vascular stent 1, making it unable to move (as shown). Figure 5 As shown), the pushing seat 8 is then pushed to move the recovery tube 5 forward relative to the vascular stent 1 until the vascular stent 1 is completely received in the recovery tube 5. After the vascular stent 1 is completely received in the recovery tube 5, the vascular stent 1 recovery device can be taken out, and the recovery of the vascular stent 1 is completed. The above is only a preferred specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, according to the technical solution and its concept of the present invention, makes equivalent replacement or changes, which should be covered within the protection scope of the present invention.

Claims

1. A vascular stent retriever, characterized in that: The invention comprises a recovery tube (5), a positioning tube (4) axially movable and inserted into the recovery tube (5), and a locking tube (3) axially movable and inserted into the positioning tube (4); the front end of the positioning tube (4) extends through the front end of the recovery tube (5), and the front end of the positioning tube (4) is provided with an expansion claw (4-1); the front end of the locking tube (3) extends through the front end of the positioning tube (4), and the front end of the locking tube (3) is provided with a locking cone (3-1); when in use, after the positioning tube (4) is axially extended into the blood vessel stent (1), the locking tube (3) is controlled to expand. ) moves backward relative to the positioning tube (4) until the locking cone (3-1) retracts into the expansion claw (4-1) and expands the expansion claw (4-1). The radial dimension of the expanded claw (4-1) is larger than the radial dimension of the rear end entrance of the vascular stent (1). At this time, the expansion claw (4-1) is tightly connected to the locking cone (3-1) and the vascular stent (1) located outside the expansion claw (4-1) is tightened and clamped. When the recovery tube (5) moves forward relative to the positioning tube (4) and the locking tube (3), the vascular stent (1) can be collected into the recovery tube (5).

2. The vascular stent retriever according to claim 1, characterized in that: The invention also comprises a control handle (6), the rear end of the positioning tube (4) is connected to the control handle (6), the control handle (6) is provided with a control button for controlling the locking tube (3) to move forward and backward along the axial direction relative to the positioning tube (4), and the control handle (6) is also provided with a pushing seat (8) for controlling the recovery tube (5) to move forward and backward along the axial direction relative to the positioning tube (4).

3. The vascular stent retriever according to claim 2, wherein: The control handle (6) is provided with a first guide groove (7), which is arranged along the axial direction of the recovery pipe (5). The push seat (8) is arranged in the first guide groove (7) and is slidably guided with the first guide groove (7). The push seat (8) is connected to the recovery pipe (5).

4. The vascular stent retriever according to claim 2, characterized in that: The invention also comprises a screw rod (3-2) arranged at the rear end of the locking tube (3) along the axial direction of the locking tube (3); a guide piece (3-3) is arranged at the front of the screw rod (3-2); a locking nut (11) used as a control button is threadedly connected to the rear of the screw rod (3-2); a second guide groove (13) is arranged on the control handle (6) and is staggered from the first guide groove (7); the second guide groove (13) is arranged along the axial direction of the locking tube (3) and is slidably guided with the guide piece (3-3); when the locking nut (11) is rotated, the screw rod (3-2) can drive the locking tube (3) to move forward and backward along the axial direction relative to the positioning tube (4).

5. The vascular stent retriever according to claim 2, wherein: The control handle (6) is provided with a first positioning groove (9), and the rear end of the positioning tube (4) is provided with a positioning ring (4-2). The positioning ring (4-2) is clamped in the first positioning groove (9) and is axially limited by the first positioning groove (9).

6. The vascular stent retriever according to claim 2, characterized in that: The inner hole of the locking tube (3) is used as a guide wire hole, and is used to insert a guide wire (2) for guidance when in use.

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