Cavity embolism system with spiral structure and conveying method

Abstract

The invention relates to the technical field of medical instruments, and provides a system for cavity embolism with a spiral structure and a conveying method.The system comprises an embolism device, an embolism device, a conveying device and an embolism device, the embolism device comprises an inner net layer and an outer net layer which are concentrically arranged, and the sparse degree of the outer net layer is greater than that of the inner net layer; the embolism device is used for being arranged outside the embolism support in a sleeving mode, and the inner ring of the spiral structure is tightly attached to the outer wall of the embolism support. According to the system, the embolism device of the spiral structure can be tightly attached to the periphery of the embolism support after being released, the diameter of the cavity part of the embolism support is increased, the whole cavity or the whole bag body is filled in a physical space occupying mode, the blocking effect is improved, internal leakage is avoided, and therefore secondary operation is avoided. Moreover, as the sparse degree of the outer net layer is larger than that of the inner net layer, the blood flow direction can be better changed, the blood flow speed can be better reduced, endothelialization substances in blood can be rapidly deposited and embolized, endothelialization is completed, and tumor cyst atrophy is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a system with a spiral structure for cavity embolization and a delivery method. Background Art

[0002] For aneurysms, the decision on whether to intervene is generally based on the size of the aneurysm. When the diameter of the aneurysm reaches the diameter that requires intervention, it can be treated by surgical means or by medical intervention using stents. Surgical operations are very traumatic. With the development of medical devices and procedures, more and more procedures are using medical intervention. When stents are used to treat aneurysms, there is a risk of endoleakage. For example, the overall endoleakage rate after endovascular repair of abdominal aortic aneurysm is as high as 20%-50%. When endoleakage occurs, it is generally resolved by re-placement of stents or embolization. Among them, the commonly used embolization device is a coil. However, in this case, not only a second operation is required, but also multiple coils need to be filled for larger endoleaks, which results in higher costs for patients. Summary of the invention

[0003] Therefore, the present invention aims to solve the technical problems in the prior art that a second operation is required for treating an aneurysm once an internal leak occurs, and that multiple spring coils need to be filled in case of a larger internal leak, resulting in high cost to the patient, thereby providing a system and delivery method for cavity embolization with a spiral structure.

[0004] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0005] On the one hand, the present invention provides a system for cavity embolization with a spiral structure, including: an embolization device, which is made of a shape memory alloy, has a spiral structure in a natural state and can stretch and shrink freely after being subjected to force; the embolization device includes an inner mesh layer and an outer mesh layer arranged concentrically, and the outer mesh layer is more sparse than the inner mesh layer; the embolization device is used to be sleeved on the outside of the embolization stent and the inner circle of the spiral structure is in close contact with the outer wall of the embolization stent to increase the diameter of the cavity part of the embolization stent.

[0006] Furthermore, the two ends of the inner mesh layer and the outer mesh layer along the axial direction of the embolic device are fixed by a tie piece, and the end of the tie piece located at the distal end of the embolic device is recessed inwards.

[0007] Furthermore, a flow-blocking film is provided between the outer mesh layer and the inner mesh layer.

[0008] Furthermore, an oxide film layer is formed on the surface of the shape memory alloy used to make the embolization device, which reduces the precipitation of nickel ions.

[0009] Furthermore, the outer reticular layer is provided with cilia that accelerate the plug-forming speed.

[0010] Furthermore, the system for cavity embolization with a spiral structure also includes an embolization stent; the embolization device is sleeved outside the embolization stent and the inner circle of the spiral structure is in close contact with the outer wall of the embolization stent to increase the diameter of the cavity part of the embolization stent.

[0011] Furthermore, the system for cavity embolization with a spiral structure also includes a delivery device, which includes an outer sleeve, a middle tube, an inner core tube, a traction wire, a first stopper, a second stopper, a third stopper and a guide wire; the outer sleeve is sleeved outside the middle tube, and a first gap for accommodating the embolization device is left between the outer sleeve and the middle tube; the first stopper is arranged on the outer wall of the middle tube and is located on one side of the distal end of the embolization device to limit the movement of the embolization device in the first gap; the traction wire is arranged in the first The middle tube is sleeved outside the inner core tube, and a second gap for accommodating the embolization bracket is reserved between the middle tube and the inner core tube; the second limiter and the third limiter are both arranged on the outer wall of the inner core tube, and are respectively located at the two ends of the embolization bracket to limit the movement of the embolization bracket in the second gap; the inner core tube is a hollow tube; the guide wire is movably inserted into the inner core tube.

[0012] On the other hand, the present invention provides a delivery method, including the system for cavity embolization with a spiral structure as described above, wherein a guide wire is delivered to a distal blood vessel above the aneurysm through an inner core tube; a delivery device reaches the upper end of the aneurysm along the guide wire; the position of the embolization device is located, and the position of the embolization device is fixed after the position of the embolization device matches the position of the aneurysm sac; the outer sleeve is unlocked, and the outer sleeve is withdrawn to release the embolization device and expand it; the middle tube is unlocked, and the middle tube is withdrawn to release the embolization stent, and the embolization stent is expanded and closely adheres to the blood vessel wall, and the embolization device is wrapped around the embolization stent.

[0013] Furthermore, when fixing the position of the embolic device, a certain force is applied to the tail end of the traction wire to prevent the embolic device from being washed away from the predetermined position by the blood flow.

[0014] Furthermore, if the release position of the embolic device is not ideal, the traction wire is pulled and the outer sleeve is pushed upward to put the embolic device into the first gap and then release it again.

[0015] The technical solution of the present invention has the following advantages:

[0016] The system for cavity embolization with a spiral structure provided by the present invention can closely fit around the embolization stent after the embolization device with a spiral structure is released, thereby increasing the diameter of the cavity part of the embolization stent, filling the entire cavity or capsule in a physical space-occupying manner, improving the blocking effect, avoiding internal leakage, and thus avoiding secondary surgery. Moreover, since the sparseness of the outer mesh layer is greater than that of the inner mesh layer, it can also better change the direction of blood flow, reduce the blood flow velocity, and allow the endothelialized substances in the blood to quickly deposit and embolize, complete endothelialization, shrink the tumor capsule, and improve the treatment effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 Schematic diagram of an embolization device (in a natural state) in a system for cavity embolization with a spiral structure in an embodiment of the present invention;

[0019] Figure 2 It is a schematic diagram of the inner mesh layer and the outer mesh layer of the embolization device with a spiral structure in the system for cavity embolization in an embodiment of the present invention;

[0020] Figure 3 It is a schematic diagram of the positional relationship between the embolization device and the embolization stent in a system for cavity embolization with a spiral structure in an embodiment of the present invention;

[0021] Figure 4 is a schematic diagram of the cilia of the embolization device with a spiral structure in the system for cavity embolization in an embodiment of the present invention;

[0022] Figure 5 Schematic diagram of an embolization device (with cilia) in a system for cavity embolization with a spiral structure in an embodiment of the present invention;

[0023] Figure 6 is a schematic diagram of a delivery device having a spiral structure in a system for cavity embolization according to an embodiment of the present invention;

[0024] Figure 7 It is a schematic diagram of the internal structure of a delivery device with a spiral structure in a system for cavity embolization in an embodiment of the present invention;

[0025] Figure 8 It is a schematic diagram of the embolization device after being released in the system for cavity embolization with a spiral structure in an embodiment of the present invention;

[0026] Fig. 9 It is a schematic diagram of the embolic stent after being released in the system for cavity embolization with a spiral structure in an embodiment of the present invention;

[0027] Fig.10 It is a schematic diagram of the delivery device with a spiral structure in the system for cavity embolization in the embodiment of the present invention when it is withdrawn.

[0028] Description of reference numerals:

[0029] 1. Embolization device; 2. Outer mesh layer; 3. Inner mesh layer; 4. Closure piece; 5. Blood vessel; 6. Embolization stent; 7. Cilia; 8. Delivery device; 9. Outer tube; 10. Middle tube; 11. Inner core tube; 12. Traction wire; 13. First gap; 14. Second gap. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are 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 therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] In the present application, the end connected to the conveying device 8 is defined as the proximal end, and the other end is defined as the distal end. It can also be understood that the end closer to the operator is the proximal end, and the other end is the distal end.

[0035] like Figure 1 , Figure 2 , Figure 3 As shown, this embodiment provides a system for cavity embolization with a spiral structure, including: an embolization device 1, which is made of shape memory alloy, has a spiral structure in a natural state and can be stretched and contracted freely after being stressed; for example, the embolization device 1 can be made of nickel-titanium alloy material through weaving and shaping processing, has a spiral structure in a natural state, and the number of spiral turns N ≥ 1. The embolization device 1 includes an inner mesh layer 3 and an outer mesh layer 2 arranged concentrically, and the sparseness of the outer mesh layer 2 is greater than that of the inner mesh layer 3; the embolization device 1 is used to be sleeved outside the embolization stent 6, and the inner circle of the spiral structure is in close contact with the outer wall of the embolization stent 6 to increase the diameter of the cavity part of the embolization stent 6.

[0036] The system for cavity embolization with a spiral structure provided in this embodiment can closely fit around the embolization stent 6 after being released, thereby increasing the diameter of the cavity part of the embolization stent 6, filling the entire cavity or capsule in a physical space-occupying manner, improving the blocking effect, avoiding internal leakage, and thus avoiding secondary surgery. Moreover, since the sparseness of the outer mesh layer 2 is greater than that of the inner mesh layer 3, it can also better change the direction of blood flow, reduce the blood flow velocity, and allow the endothelialized substances in the blood to quickly deposit and embolize, complete endothelialization, shrink the tumor capsule, and improve the treatment effect.

[0037] Wherein, the two ends of the inner mesh layer 3 and the outer mesh layer 2 are fixed by a tie piece 4 along the axial direction of the embolic device 1, and the end of the tie piece 4 located at the distal end of the embolic device 1 is concave inward. For example, the tie piece 4 can be made of stainless steel alloy, and the tie piece 4 is used to wrap the tie of the inner mesh layer 3 and the outer mesh layer 2, so that it is more convenient to use the tie piece 4 to pull the entire embolic device 1 for the proximal end; and for the distal end, the concave tie piece 4 can prevent the stainless steel tie piece 4 from protruding to form a sharp point to cause harm to the human body.

[0038] Wherein, a flow-blocking film is arranged between the outer mesh layer 2 and the inner mesh layer 3. For example, the flow-blocking film can be fixed on the inner side close to the outer mesh layer 2, and the material of the flow-blocking film can be a degradable artificial synthetic polymer material, a natural polymer material, or a non-degradable artificial synthetic polymer material, a natural polymer material. For example, the material of the flow-blocking film includes but is not limited to polyester fiber, polyurethane, polylactic acid, chitosan, polytetrafluoroethylene, and animal mucosa. Such an arrangement can improve the flow-blocking performance of the device.

[0039] The surface of the shape memory alloy used to make the embolization device 1 is formed with an oxide film layer that reduces the precipitation of nickel ions. For example, the nickel-titanium alloy used to make the embolization device 1 can be subjected to surface treatment, including heat treatment to form an oxide film layer, surface coating strengthening by physical or chemical methods, and surface cleaning treatment to form a dense oxide layer, such as polishing treatment, plasma treatment, and one or more of these methods can be used. This arrangement can reduce the precipitation of nickel ions and improve the corrosion resistance of the material.

[0040] like Figure 4 , Figure 5 As shown, the outer mesh layer 2 is provided with cilia 7 that accelerate the embolization speed. For example, PET or nylon cilia 7 can be fixed on the outer mesh layer 2 of the embolization device 1 by sewing to form the embolization device 1 with cilia 7. Such a configuration can increase the embolization speed of the embolization device 1.

[0041] The system for cavity embolization with a spiral structure further includes an embolization stent 6; the embolization device 1 is sleeved outside the embolization stent 6 and the inner ring of the spiral structure is in close contact with the outer wall of the embolization stent 6 to increase the diameter of the cavity of the embolization stent 6. For example, the embolization stent 6 can be a coated stent. For example, the embolization stent 6 can also be a bare stent.

[0042] like Figure 6 , Figure 7 As shown, the system for cavity embolization with a spiral structure also includes a conveying device 8, which includes an outer sleeve 9, a middle tube 10, an inner core tube 11, a traction wire 12, a first stopper, a second stopper, a third stopper and a guide wire; the outer sleeve 9 is sleeved outside the middle tube 10, and a first gap 13 for accommodating the embolization device 1 is left between the outer sleeve 9 and the middle tube 10; the first stopper is arranged on the outer wall of the middle tube 10 and is located on one side of the distal end of the embolization device 1 to limit the movement of the embolization device 1 in the first gap 13; the traction wire 12 is arranged in the first In the gap 13, one end is connected to the constriction piece 4 at the proximal end of the embolization device 1, and the other end extends out from the first gap 13 and is used to be connected to an external device for applying traction; the middle tube 10 is sleeved outside the inner core tube 11, and a second gap 14 for accommodating the embolization bracket 6 is reserved between the middle tube 10 and the inner core tube 11; the second limiter and the third limiter are both arranged on the outer wall of the inner core tube 11, and are respectively located at the two ends of the embolization bracket 6 to limit the movement of the embolization bracket 6 in the second gap 14; the inner core tube 11 is a hollow tube; the guide wire is movably inserted into the inner core tube 11.

[0043] Specifically, the delivery device 8 is composed of three layers of nested sheath tubes, which are respectively an outer sleeve 9, a middle tube 10 and an inner core tube 11 from the outside to the inside. The first gap 13 between the outer sleeve 9 and the middle tube 10 is about 1 mm, and the embolization device 1 is pre-installed between the outer sleeve 9 and the middle tube 10. The first stopper can be located on the upper side wall of the outer surface of the middle tube 10. Such a setting can prevent the embolization device 1 from moving in the first gap 13. There is a traction wire 12 between the outer sleeve 9 and the middle tube 10, one end of the traction wire 12 extends from the proximal end of the first gap 13, and the other end is connected to the constriction piece 4 at the proximal end of the embolization device 1. The embolization stent 6 is pre-installed in the second gap 14 formed between the inner core tube 11 and the middle tube 10. The second stopper and the third stopper are set on the outer surface of the inner core tube 11 according to the length of the embolization stent 6 to prevent the embolization stent 6 from moving in the second gap 14. The inner core tube 11 is in a hollow state, and its size should allow a guide wire, such as a superhard guide wire, a loach guide wire, etc. to pass smoothly.

[0044] Another embodiment provides a delivery method, including the system for cavity embolization with a spiral structure as described above, wherein a guide wire is delivered to the distal blood vessel 5 above the aneurysm through an inner core tube 11; a delivery device 8 reaches the upper end of the aneurysm along the guide wire; the position of the embolization device 1 is positioned, and the position of the embolization device 1 is fixed after the position of the embolization device 1 matches the position of the aneurysm sac; the outer sleeve 9 is unlocked, and the outer sleeve 9 is withdrawn to release the embolization device 1 and expand it; the middle tube 10 is unlocked, and the middle tube 10 is withdrawn to release the embolization stent 6, and the embolization stent 6 is expanded and tightly attached to the wall of the blood vessel 5, and the embolization device 1 is wrapped around the embolization stent 6.

[0045] When fixing the position of the embolic device 1 , a certain force is applied to the tail end of the traction wire 12 to prevent the embolic device 1 from being washed away from the predetermined position by the blood flow.

[0046] If the release position of the embolic device 1 is not ideal, the traction wire 12 is pulled and the outer sleeve 9 is pushed upward to put the embolic device 1 into the first gap 13 and then release it again.

[0047] like Figure 8 , Fig. 9 as well as Fig.10As shown, when delivering the embolic stent 6 and the embolic device 1, first, the guide wire is delivered to the distal blood vessel 5 above the aneurysm through the inner core tube 11, and the delivery system reaches the upper end of the aneurysm along the guide wire, and the position of the embolic device 1 is located under ultrasound or DSA, so that the embolic device 1 can match the position of the aneurysm sac, and then the embolic device 1 is fixed. Unlock the outer sleeve 9 of the delivery device 8, withdraw the outer sleeve 9, release the embolic device 1 and expand it, at this time, the embolic device 1 will be washed by the blood flow, in order to prevent the embolic device 1 from being washed away from the predetermined position by the blood flow, a certain force can be applied to the tail end of the traction wire 12; at the same time, if the release position is not ideal, the traction wire 12 can be pulled and the outer sleeve 9 can be pushed up to put the occluder into the delivery device 8 and release it again to achieve an ideal release effect. Then, the middle tube 10 of the delivery device 8 is unlocked, and the middle tube 10 is withdrawn to release the embolization stent 6. After the embolization stent 6 expands, it is closely attached to the inner wall of the blood vessel 5. The embolization device 1 is wrapped around the embolization stent 6, and the effect is as follows: Fig. 9 Finally, the traction wire 12 is twisted to unlock the connection between the traction wire 12 and the embolization device 1, and the traction wire 12 is withdrawn, and the inner core tube 11 is withdrawn at the same time, so that the inner core layer is withdrawn from the position below the embolization stent 6, such as Fig.10 , the delivery device 8 withdraws from the blood vessel 5 to complete the release.

[0048] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A system for cavity embolization with a spiral structure, characterized in that: include: The embolization device (1) is made of a shape memory alloy, has a spiral structure in a natural state, and can freely stretch and shrink when subjected to force; the embolization device (1) includes an inner mesh layer (3) and an outer mesh layer (2) arranged concentrically, and the sparseness of the outer mesh layer (2) is greater than that of the inner mesh layer (3); the embolization device (1) is used to be sleeved outside an embolization stent (6), and the inner circle of the spiral structure is tightly attached to the outer wall of the embolization stent (6), so as to increase the diameter of the cavity part of the embolization stent (6).

2. The system for cavity embolization having a spiral structure according to claim 1, characterized in that: The two ends of the inner mesh layer (3) and the outer mesh layer (2) are fixed by a tie piece (4) along the axial direction of the embolic device (1), and the end of the tie piece (4) located at the far end of the embolic device (1) is recessed inwards.

3. The system for cavity embolization having a spiral structure according to claim 1, characterized in that: A flow-blocking film is provided between the outer mesh layer (2) and the inner mesh layer (3).

4. The system for cavity embolization having a spiral structure according to claim 1, characterized in that: An oxide film layer for reducing the precipitation of nickel ions is formed on the surface of the shape memory alloy used to make the embolization device (1).

5. The system for cavity embolization having a spiral structure according to claim 1, characterized in that: The outer network layer (2) is provided with cilia (7) for accelerating the plug-forming speed.

6. The system for cavity embolization having a spiral structure according to claim 1, characterized in that: Also included is an embolic stent (6); The embolization device (1) is sleeved outside the embolization stent (6), and the inner circle of the spiral structure is in close contact with the outer wall of the embolization stent (6), so as to increase the diameter of the cavity part of the embolization stent (6).

7. The system for cavity embolization having a spiral structure according to claim 6, characterized in that: It also includes a conveying device (8), wherein the conveying device (8) includes an outer sleeve (9), a middle tube (10), an inner core tube (11), a traction wire (12), a first stopper, a second stopper, a third stopper and a guide wire; The outer sleeve (9) is sleeved outside the middle tube (10), and a first gap (13) for accommodating the embolization device (1) is reserved between the outer sleeve (9) and the middle tube (10); The first stopper is arranged on the outer wall of the middle tube (10) and is located on one side of the distal end of the embolization device (1) to limit the movement of the embolization device (1) in the first gap (13); The traction wire (12) is arranged in the first gap (13), one end of which is connected to the constriction piece (4) at the proximal end of the embolization device (1), and the other end of which extends out from the first gap (13) and is used to be connected to an external device for applying traction force; The middle tube (10) is sleeved outside the inner core tube (11), and a second gap (14) for accommodating the embolization stent (6) is left between the middle tube (10) and the inner core tube (11); The second stopper and the third stopper are both arranged on the outer wall of the inner core tube (11) and are respectively located at two ends of the embolization bracket (6) to limit the movement of the embolization bracket (6) in the second gap (14); The inner core tube (11) is a hollow tube; The guide wire is movably inserted into the inner core tube (11).

8. A method of conveying, characterized in that: comprising the system for cavity embolization having a spiral structure according to claim 7, Delivering the guide wire through the inner core tube (11) to the distal blood vessel (5) above the aneurysm; The delivery device (8) is passed along the guide wire to the upper end of the aneurysm; Positioning the embolization device (1), and fixing the position of the embolization device (1) after the embolization device (1) matches the position of the aneurysm sac; Unlocking the outer sleeve (9), withdrawing the outer sleeve (9), so that the embolization device (1) is released and expands; The middle tube (10) is unlocked, and the middle tube (10) is withdrawn to release the embolization stent (6). After the embolization stent (6) expands, it is closely attached to the wall of the blood vessel (5), and the embolization device (1) is wrapped around the embolization stent (6).

9. The conveying method according to claim 8, characterized in that: When fixing the position of the embolic device (1), a certain force is applied to the tail end of the traction wire (12) to prevent the embolic device (1) from being washed away from the predetermined position by the blood flow.

10. The conveying method according to claim 8, characterized in that: If the release position of the embolization device (1) is not ideal, the traction wire (12) is pulled and the outer sleeve (9) is pushed upward to put the embolization device (1) into the first gap (13) and then release it again.

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