Degradable embolism device

Abstract

The embodiment of the utility model relates to a degradable embolism device. The degradable embolism device comprises a skeleton main body, hydrogel, a butt joint sleeve, a connecting line, a first bonding point and a second bonding point, wherein the skeleton main body is of a woven structure, and hydrogel is borne in the skeleton main body; two ends of the hydrogel are respectively fixed with two ends of the skeleton main body; the butt joint sleeve is connected with the far end of the skeleton main body; the plug device is connected with the external conveying rod through the connecting line; the far end of the skeleton main body and the far end of the hydrogel are bonded and fixed through the first bonding point; and the near end of the skeleton main body, the near end of the hydrogel, the butt-joint sleeve and the connecting line are bonded and fixed through the second bonding points. The degradable embolism device has high flexibility and can be formed in an aneurysm cavity in a self-adaptive mode; and in addition, the implant has the characteristic of being completely degradable, so that the implant can be completely degraded and absorbed by human tissues or discharged out of the body after the aneurysm is normally healed.

Description

Technical Field

[0001] The utility model relates to the medical field, in particular to a degradable embolization device. Background Art

[0002] Intracranial aneurysms are mostly abnormal bulges occurring on the intracranial artery wall, and are the leading cause of subarachnoid hemorrhage. Among cerebrovascular accidents, it ranks third after cerebral thrombosis and hypertensive intracerebral hemorrhage. It can occur at any age, and most cases occur in middle-aged and elderly women aged 40 to 60.

[0003] The technology of neurointerventional treatment of intracranial aneurysms has been relatively mature. The treatment instruments involved include embolization coils, flow diversion dense mesh stents, and a new generation of intrasacculated flow disturbance devices, etc. These existing interventional treatment technologies have played an important role in the treatment of aneurysms with different morphologies. However, the existing technologies all have common deficiencies, that is, these instruments need to be pre-shaped, and they are all permanently implanted into the cerebral blood vessels as inert materials. On the one hand, it may cause some inflammatory reactions or thrombus events to varying degrees. On the other hand, metal materials will produce artifacts, and patients must undergo invasive angiography examinations after surgery to confirm whether the aneurysm has truly healed. Summary of the Utility Model

[0004] The purpose of the utility model is to address the defects of the existing technology and provide a degradable embolization device with high flexibility. It can adaptively form in the aneurysm cavity without the need for pre-shaping like the existing mature coil or intrasacculated flow disturbance device products; and it has the characteristic of complete degradability, enabling the implanted device to be completely degraded and absorbed by human tissues or excreted from the body after the aneurysm has completed normal healing.

[0005] To achieve the above purpose, the utility model provides a degradable embolization device, which includes a framework body, a hydrogel, a docking sleeve, a connecting wire, a first bonding point, and a second bonding point;

[0006] Among them, the framework body adopts a braided structure, and the hydrogel is carried inside the framework body;

[0007] Both ends of the hydrogel are fixed to both ends of the framework body respectively. When the hydrogel encounters liquid, it swells inside the framework body;

[0008] The docking sleeve is connected to the distal end of the framework body, and the docking between the embolization device and the external delivery rod is realized through the docking sleeve;

[0009] The connecting wire connects the embolization device and the external delivery rod;

[0010] The first bonding point bonds and fixes the distal end of the framework body and the distal end of the hydrogel;

[0011] The second bonding point bonds and fixes the proximal end of the framework body, the proximal end of the hydrogel, the docking sleeve and the connecting wire.

[0012] Preferably, the framework body is a cross-woven structure or a spiral-woven structure. Among them, the pitch range of the spiral-woven structure is 0.03 - 0.12 mm.

[0013] Preferably, the framework body is a tubular object woven from a biodegradable polymer filament. The outer diameter range of the framework body is 0.2 - 0.5 mm. The diameter range of the biodegradable polymer filament is 0.02 - 0.10 mm. The number of strands of the biodegradable polymer filament used is 2 - 12 strands, and the braiding density PPI is 10 - 100.

[0014] More preferably, the biodegradable polymer filament is one or more of poly(p-dioxanone), polylactic acid, chitosan, polyurethane, poly(lactic acid - glycolic acid) copolymer.

[0015] Preferably, the hydrogel is an alginate-based hydrogel, gelatin, polyethylene glycol dimethacrylate hydrogel, chitosan or polyurethane;

[0016] The hydrogel contains a developer such as tungsten, bismuth or barium sulfate.

[0017] Preferably, the length of the docking sleeve is 0.1 - 0.5 mm, and the outer diameter is 0.2 - 0.5 mm.

[0018] Preferably, the material of the docking sleeve is poly(p-dioxanone), polylactic acid, chitosan, polyurethane, poly(lactic acid - glycolic acid) copolymer, platinum-iridium alloy or platinum-tungsten alloy.

[0019] Preferably, the breaking strength of the connecting wire is not less than 0.5 N;

[0020] The distal end of the connecting wire is fixed to the proximal mesh of the framework body by winding or knotting;

[0021] The proximal end of the connecting wire is flat or ball-cap shaped.

[0022] Preferably, the material of the connecting wire is one or more of POE, HDPE, PP, PDO, PLA, PLGA.

[0023] Preferably, the first bonding point and the second bonding point are bonded with an ultraviolet light-curing glue.

[0024] An embolic device provided by an embodiment of the present utility model breaks the conventional thinking that existing interventional devices must be pre-shaped, and designs a highly flexible degradable device. This device does not require pre-shaping outside the body. By providing the flexibility of the device itself, it can adaptively form in the aneurysm cavity. Moreover, the entire device has the characteristic of being completely degradable. Its degradable material is divided into a skeleton main body and a core hydrogel. The skeleton main body is a tubular object woven from degradable polymer filaments. The braided filaments and PPI of the tube body are adjustable. The skeleton main body can well fix the core hydrogel inside the braided tube, so as to realize the delivery of the device in a matching microcatheter. Since the hydrogel undergoes a small volume change after contacting water and is controllable, there is no need to worry about its overflowing from the skeleton main body. In addition, the skeleton main body is designed as a structure of a braided tube. When the skeleton main body bears the core hydrogel, there is no need to additionally set tensile wires or anti-unwinding wires, which not only ensures the safety of the device during use, but also does not reduce the flexibility of the entire device. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 FIG. is a schematic structural diagram of a degradable embolic device provided by an embodiment of the present utility model in a dry state;

[0026] Figure 2 FIG. is a schematic structural diagram of another degradable embolic device provided by an embodiment of the present utility model in a dry state;

[0027] Figure 3 FIG. is a schematic structural diagram of a degradable embolic device provided by an embodiment of the present utility model after swelling;

[0028] Figure 4 FIG. is a schematic diagram of the intraoperative application scenario of a degradable embolic device provided by an embodiment of the present utility model in an aneurysm cavity;

[0029] Figure 5 FIG. is a schematic diagram of the postoperative scenario of an aneurysm cavity provided by an embodiment of the present utility model;

[0030] Figure 6 FIG. is another schematic diagram of the postoperative scenario of an aneurysm cavity provided by an embodiment of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The technical solutions of the present utility model will be further described in detail below with reference to the drawings and embodiments.

[0032] Figure 1 FIG. is a schematic structural diagram of a degradable embolic device provided by an embodiment of the present utility model. As Figure 1 shown, the degradable embolic device 10 specifically includes a skeleton main body 1, a hydrogel 2, a docking sleeve 3, a connecting line 4, a first bonding point 5, and a second bonding point 6. The following will be combined with Figure 1Specifically introduce the structures of various parts of the degradable embolization device 10.

[0033] The skeleton main body 1 is integrally of a braided structure. The interior of the skeleton main body 1 is used to carry the hydrogel 2, enabling it to maintain a stable shape and facilitating its pushing within the microcatheter. In this embodiment, the skeleton main body 1 is a tubular object made of braided degradable polymer filaments. The outer diameter of the skeleton main body 1 ranges from 0.2 - 0.5 mm. The degradable polymer material used is preferably made into round filaments. The diameter range of the degradable polymer filaments is preferably 0.02 - 0.10 mm. The number of the degradable polymer filaments used, that is, the number of the filaments selected, is 2 - 12 strands. The braiding density PPI is 10 - 100. The braided mesh size and the overall flexibility of the skeleton main body 1 can be regulated by the number of filaments and PPI. Further, the skeleton main body 1 here can specifically adopt a cross-braided structure or a spiral-braided structure. Among them, Figure 1 It is an integrated cross-braided tubular structure. The pitch range of the spiral-braided structure is 0.03 - 0.12 mm. The spiral braiding has better flexibility than the cross braiding.

[0034] In a preferred embodiment, its skeleton main body 1 is a tubular object made of braided degradable polymer filaments. The degradable polymer filaments include but are not limited to one or more of poly(p-dioxanone), polylactic acid, chitosan, polyurethane, poly(lactic-co-glycolic acid). Due to the special integrated braided tube structure of the skeleton main body 1, it has strong axial tensile strength by itself. When the skeleton main body 1 carries the core hydrogel 2, there is no need to additionally set tensile wires or anti-unwinding wires, which not only ensures the safety of the device during use but also does not reduce the flexibility of the entire device.

[0035] The hydrogel 2, that is, the core hydrogel 2, has its two ends respectively fixed to the two ends of the skeleton main body 1. When the hydrogel 2 encounters a liquid, it swells within the skeleton main body 1. Specifically, the core hydrogel 2 is a completely degradable hydrogel 2 material, preferably biocompatible materials such as alginate hydrogels 2, gelatin, polyethylene glycol dimethacrylate hydrogels 2, chitosan, polyurethane, etc. In the dry state, the diameter of the core hydrogel 2 is slightly smaller than the inner diameter of the skeleton main body 1. When the core hydrogel 2 encounters water or blood, it undergoes appropriate swelling. By controlling the swelling degree of the core hydrogel 2, the maximum diameter after swelling will not exceed the outer diameter of the skeleton main body 1. Since the density of the core hydrogel 2 is close to that of water, it becomes very soft when encountering water or blood. In addition, in order to increase the imaging performance of the core hydrogel 2 under fluoroscopy, the hydrogel 2 can also carry a radiopaque agent such as tungsten, bismuth, or barium sulfate. That is to say, an appropriate amount of radiopaque agent, such as tungsten, bismuth, and barium sulfate, can be doped or added into the core hydrogel 2.

[0036] The embolization device 10 of this embodiment makes full use of the flexibility of the skeleton main body 1 and the core hydrogel 2. In its natural state, it is straight and does not need to be pre-shaped. It can adaptively form in the aneurysm cavity and achieve a good embolization result. The inner diameter range of the microcatheter that it can match is 0.015 inches - 0.033 inches.

[0037] The docking sleeve 3 is connected to the distal end of the skeleton main body 1 at the distal end and to the external delivery rod at the proximal end. Thus, the docking between the embolization device 10 and the external delivery rod is achieved through the docking sleeve 3, and then a smooth transition connection between the two is realized. Specifically, the docking sleeve 3 is a hollow structure, and its inner cavity can be docked and connected as a whole with the external delivery rod through a polymer or metal wire. The docking part of the external delivery rod can also be processed into a hollow shape. The docking between the hollow tubes is relatively smooth, making the skeleton main body 1 more smooth when released or pushed. In this embodiment, the material of the docking sleeve 3 is polydioxanone, polylactic acid, chitosan, polyurethane, poly(lactic-co-glycolic acid), platinum-iridium alloy or platinum-tungsten alloy. It can be understood that the material selected for the docking sleeve 3 is the same as that of the skeleton main body 1, or for better imaging performance, a metal material can also be selected, such as platinum-iridium alloy or platinum-tungsten alloy. Since the size of the docking sleeve 3 is very small, the length is preferably 0.1 - 0.5 mm, and the outer diameter is preferably 0.2 - 0.5 mm, which does not affect the degradation performance of the whole device.

[0038] The connecting line 4 connects the embolization device 10 with the external delivery rod. Specifically, the distal end of the connecting line 4 is fixed to the proximal mesh hole of the skeleton main body 1 by winding or knotting. The material of the connecting line 4 here is a polymer material, including but not limited to one or more of POE, HDPE, PP, PDO (dioxanone), PLA (polylactic acid), PLGA (poly(lactic-co-glycolic acid)). The connecting line 4 has sufficient breaking strength, not less than 0.5 N, to ensure the reliability of the connection between the degradable embolization device 10 and its delivery rod, and will not be detached prematurely.

[0039] It should be noted that the proximal end of the connecting line 4 is flat 41 or ball-cap shaped 42. Specifically, the embolization device 10 is connected to the delivery rod through the connecting line 4, and can be separated by electrolytic detachment or mechanical detachment. When using electrolytic detachment, the proximal end of the connecting line 4 can be processed into a flat shape, specifically as Figure 1 shown. When using mechanical detachment, the proximal end of the connecting line 4 can be processed into a ball-cap shape, specifically as Figure 2 shown. Processing into a ball-cap shape 42 is beneficial to the local connection under the mechanical detachment mechanism.

[0040] The first bonding point 5 bonds and fixes the distal end of the skeleton main body 1 and the distal end of the hydrogel 2.

[0041] The second bonding point 6 bonds and fixes the proximal end of the framework main body 1, the proximal end of the hydrogel 2, the docking sleeve 3 and the connecting wire 4 together. Specifically, the distal end of the connecting wire 4 is fixed to the proximal mesh holes of the framework main body 1 by winding or knotting, and finally, it is bonded to the proximal end of the hydrogel 2 and the docking sleeve 3 using ultraviolet curable glue.

[0042] Preferably, both the above-mentioned first bonding point 5 and second bonding point 6 are bonded using ultraviolet curable glue to achieve a good fixing effect.

[0043] The above is the introduction of the structure of the degradable embolization device 10 provided by the embodiment of the present invention. To better understand its application process and effects, the following will be combined with Figures 1 to 6 for specific description.

[0044] The degradable embolization device 10 provided in this embodiment is delivered along the microcatheter 20 into the cavity of the aneurysm 50. During the intraoperative pushing and filling process, the core hydrogel 2 in the degradable embolization device 10 is doped with tungsten powder developer, and the whole body has good radiopacity; and because the degradable embolization device 10 has good flexibility when encountering blood, it can adaptively form a basket in the cavity of the aneurysm 50, and at the same time induce a large amount of thrombus 30. One or more degradable embolization devices 10 can be filled to achieve the effect of dense embolization during the operation. Since the main body of the degradable embolization device 10 is made of degradable hydrogel material and has a small density, it will not produce an obvious gravity effect.

[0045] After a period of time after the operation, about 1 - 3 months or so, all the degradable embolization devices 10 in the cavity of the aneurysm 50 are degraded and absorbed by the human tissue. During the degradation process of the hydrogel 2 material, due to the biological activity of the hydrogel, it is more conducive to the crawling of endothelial cells at the aneurysm neck, forming a dense endothelialized membrane 40 at the neck of the aneurysm 50, so that the aneurysm is completely healed. At the same time, only thrombus remains in the cavity of the aneurysm 50 and is partially absorbed by the human tissue, making the aneurysm show a shrinking trend. If the patient needs to have a follow-up examination at this stage, due to the absence of interference from any metal material artifacts, only non-invasive CTA or MRI examinations are required to determine whether the aneurysm 50 is completely healed. However, when using traditional interventional devices (such as coils or dense mesh stents), invasive angiography follow-up examinations are required to clearly determine the healing situation of the aneurysm. The device provided by the present invention benefits the patient significantly during the clinical follow-up stage.

[0046] As time goes by, about 24 months or more after the operation, the thrombus in the aneurysm cavity will be further absorbed until it is finally completely absorbed. At this time, the aneurysm is close to disappearing, and the dense endothelialized membrane formed at the original aneurysm neck reshapes the blood vessel, and no foreign bodies or materials will remain. The arterial blood vessel will return to a completely normal state.

[0047] An embolic device provided by an embodiment of the present utility model breaks the conventional thinking that existing interventional devices must be pre-shaped, and designs a highly flexible degradable device. This device does not require external pre-shaping. By providing the flexibility of the device itself, it can adaptively form in the aneurysm cavity. Moreover, the entire device has the characteristic of being completely degradable. Its degradable material is divided into a skeleton main body and a core hydrogel. The skeleton main body is a tubular object woven from degradable polymer filaments. The woven filaments of the tube body and the PPI are adjustable. The skeleton main body can well fix the core hydrogel inside the woven tube, so as to realize the delivery of the device in a matching microcatheter. Since the hydrogel undergoes a small volume change after contacting water and is controllable, there is no need to worry about its overflowing from the skeleton main body. In addition, the skeleton main body is designed as a structure of a woven tube. When the skeleton main body carries the core hydrogel, there is no need to additionally set tensile wires or anti-unwinding wires, which not only ensures the safety of the device during use, but also does not reduce the flexibility of the entire device.

[0048] In the present utility model, the term "a plurality of" refers to two or more, unless otherwise clearly defined. Terms such as "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0049] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0050] In the description of this specification, the description of terms such as "a specific embodiment", "some embodiments", "an embodiment", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0051] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present utility model. It should be understood that the above description is only the specific embodiments of the present utility model and is not intended to limit the protection scope of the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A degradable embolization device, characterized in that, The degradable embolization device includes a framework body, a hydrogel, a docking sleeve, a connecting line, a first bonding point, and a second bonding point; Among them, the framework body adopts a braided structure, and the hydrogel is carried inside the framework body; Both ends of the hydrogel are fixed to both ends of the framework body respectively. When the hydrogel encounters a liquid, it swells inside the framework body; The docking sleeve is connected to the distal end of the framework body, and the docking between the embolization device and an external delivery rod is achieved through the docking sleeve; The connecting line connects the embolization device and an external delivery rod; The first bonding point bonds and fixes the distal end of the framework body and the distal end of the hydrogel; The second bonding point bonds and fixes the proximal end of the framework body, the proximal end of the hydrogel, the docking sleeve, and the connecting line.

2. The degradable embolization device according to claim 1, wherein The framework body is a cross-braided structure or a helical-braided structure. Among them, the pitch range of the helical-braided structure is 0.03 - 0.12 mm.

3. The degradable embolization device according to claim 1, wherein The framework body is a tubular object woven from degradable polymer filaments. The outer diameter range of the framework body is 0.2 - 0.5 mm. The diameter range of the degradable polymer filaments is 0.02 - 0.10 mm. The number of strands of the used degradable polymer filaments is 2 - 12, and the braiding density PPI is 10 - 100.

4. The degradable embolization device according to claim 1, wherein, The length of the docking sleeve is 0.1 - 0.5 mm, and the outer diameter is 0.2 - 0.5 mm.

5. The degradable embolization device according to claim 1, characterized in that, The material of the docking sleeve is poly(p-dioxanone), polylactic acid, chitosan, polyurethane, poly(lactic-co-glycolic acid), platinum-iridium alloy, or platinum-tungsten alloy.

6. The degradable embolization device according to claim 1, characterized in that, The breaking strength of the connecting line is not less than 0.5 N; The distal end of the connecting line is fixed to the proximal mesh hole of the framework body by winding or knotting; The proximal end of the connecting line is flat or ball-cap shaped.

7. The degradable embolization device according to claim 1, wherein, The first bonding point and the second bonding point are bonded with an ultraviolet-curing glue.

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