Magnetically controllable liquid embolization robot and magnetic control embolization system

Abstract

Provided are a magnetically controllable liquid embolization robot and a magnetic control embolization system, which belong to the field of medical instruments. The magnetically controllable liquid embolization robot uses a pure liquid embolization technology; a mixed liquid of an embolization material and magnetic powder particles exists in vitro; in use, the mixed liquid is injected into an in-vivo blood environment and fixed to a target part by means of magnetic control, or flows in a complex zigzag blood vessel to the target part and is fixed by means of magnetic control; and the mixed liquid has an ion cross-linking reaction in the blood environment, and is completely solidified into a gel-state at the target part so as to complete embolization. The robot can resist blood flow impact, does not need an additional device for blockage in the whole operation process, breaks through an existing solid embolization and solid-liquid combined embolization technology, and is safe and flexible.

Description

A magnetically controlled liquid embolization robot and a magnetically controlled embolization system Technical Field

[0001] The present invention relates to medical devices, and in particular to a magnetically controlled liquid embolization robot and a magnetically controlled embolization system. Background Art

[0002] Compared to traditional surgery, embolization is a minimally invasive interventional procedure that is easy to perform, requires minimal trauma, and offers a quick recovery time, with a low probability of postoperative recurrence. However, the use of liquid embolic materials still faces several challenges. Unlike solid mechanical devices, existing liquid embolic agents are mostly medium- to long-term embolic agents. If ectopic embolism and excessive reflux occur under the impact of blood flow in the body, they can be fatal to the patient. Furthermore, when liquid embolic materials are located within tortuous blood vessels, catheter insertion and post-embolization removal can be difficult.

[0003] Summary of the Invention

[0004] To address the aforementioned problems in the prior art, the present invention aims to design and manufacture a magnetically controlled liquid embolization robot to improve the safety and flexibility of using liquid embolic materials. Furthermore, the present invention proposes a magnetically controlled embolization system for implementing embolization operations.

[0005] In order to achieve the above technical objectives, the technical solution of this case is as follows.

[0006] Firstly, this case proposes a magnetically controlled liquid embolization robot.

[0007] The liquid embolization robot is a mixed solution of embolic material and magnetic powder particles in vitro, with the mass proportion of magnetic powder particles being 15%-65%. When in use, the mixed solution is injected into the blood environment in the body and fixed at the target site by magnetic control, or it is flowed to the target site by magnetic control and fixed, and ionic cross-linking reaction occurs in the blood environment and it is completely solidified into a colloid at the target site to achieve embolism.

[0008] In the above technical solution, in one preparation method of the liquid embolization robot, the preparation steps include:

[0009] EVOH (ethylene-vinyl alcohol) copolymer and DMSO (dimethyl sulfoxide) are used as embolic materials, wherein the weight proportion of EVOH (ethylene-vinyl alcohol) copolymer solid particles in the mixed solution is 8% to 16%;

[0010] Dissolve EVOH (ethylene-vinyl alcohol) copolymer solid particles in DMSO (dimethyl sulfoxide) to obtain a clear and transparent mixed liquid;

[0011] Magnetic powder particles are added to the mixed liquid to obtain a liquid embolization robot solution.

[0012] In one embodiment of the above technical solution, the EVOH (ethylene vinyl alcohol) copolymer content / concentration is controlled to control the time it takes for the liquid embolization robot to fully solidify through ionic crosslinking in the blood environment. The higher the EVOH concentration, the faster the solidification, and the harder the solidified gel.

[0013] In one embodiment of the above technical solution, the magnetic powder particles are preferably NdFeB (neodymium iron boron).

[0014] In one embodiment of the above technical solution, after adding the magnetic powder particles, an anti-settling agent is added with a concentration of 0.2%-0.5%.

[0015] In one embodiment of the above technical solution, one way to achieve dissolution is to use water bath heating.

[0016] Secondly, this case proposes a magnetically controlled embolization system, which includes a magnetically controlled device and any of the liquid embolization robots described above. The magnetically controlled device provides a magnetic field for the liquid embolization robot to be fixed at the target site or to flow to the target site and be fixed.

[0017] In the above technical solution, one form of the magnetron device is a spherical rotating magnet.

[0018] In the above technical solution, the system further comprises a catheter, which is used to push the uniform liquid embolic robot solution into the blood vessel or the target site requiring embolization.

[0019] In the above technical solution, the catheter is flushed with DMSO (dimethyl sulfoxide) solvent before use.

[0020] In a third aspect, this case proposes a method for preparing a magnetically controllable liquid embolization robot, the steps comprising:

[0021] EVOH (ethylene-vinyl alcohol) copolymer and DMSO (dimethyl sulfoxide) are used as embolic materials, wherein the weight proportion of EVOH (ethylene-vinyl alcohol) copolymer solid particles in the mixed solution is 8% to 16%;

[0022] Dissolve EVOH (ethylene-vinyl alcohol) copolymer solid particles in DMSO (dimethyl sulfoxide) to obtain a clear and transparent mixed liquid;

[0023] Magnetic powder particles accounting for 15% to 25% by mass are added to the mixed liquid to obtain a liquid embolization robot solution.

[0024] The beneficial technical effects of this case are:

[0025] (1) The designed liquid embolization robot can be injected into the body in liquid form and spontaneously formed into a fluid soft colloid based on the vascular structure in the blood environment. This allows it to flow to the target site in complex and tortuous blood vessels under magnetic control before it is completely solidified. It is not affected by the size, shape and angle of the blood vessels, thereby improving the flexibility and safety of embolization.

[0026] (2) According to the distance between the embolization site and the injection site, the time it takes for the liquid embolization robot to reach the embolization site is evaluated, and then the appropriate EVOH content / concentration is adopted to control the complete solidification time of the liquid embolization robot, thereby further improving the safety of embolization.

[0027] (3) By using magnetic control fixation at the target site, the liquid embolization robot can resist the impact of blood flow. The entire operation process does not require the use of additional devices for blocking. The liquid embolization robot solution is continuously injected into the blood environment and completely solidified at the target site to complete the embolization, thereby improving the safety of the embolization. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] Figure 1 is a schematic diagram of an embodiment of liquid embolization robot production to complete embolization.

[0030] Figure 2. Schematic diagram of the three working modes of the liquid embolization robot. (A) in the figure is a non-magnetic control working mode. In this working mode, embolization may not be possible or the embolization effect is poor. (B) in the figure is magnetically fixed at the target site. In this working mode, complete embolization is achieved by continuously injecting the embolization robot liquid into the target site and solidifying it. (C) in the figure is a magnetically driven liquid embolization robot flowing in the blood vessel until it is fixed at the target site to achieve embolization. DETAILED DESCRIPTION

[0031] Embolization is an interventional procedure that blocks blood flow within an abnormal blood supply system by introducing special embolic materials. This procedure can be used for a variety of body organs and indications. It was first used to treat fistulas in 1933, and began to be used to treat the peripheral vascular system in 1968. Today, it is often used to treat localized vascular abnormalities such as aneurysms.

[0032] Embolic materials can be divided into mechanical devices, microparticles and liquids. For mechanical embolic materials, it is difficult to reach the distal peripheral vascular system and difficult to introduce them. For microparticle embolic materials, although they are easier to enter the blood vessels than mechanical devices, they may also be unable to enter due to the ruggedness or angle of the blood vessels. For existing liquid embolic materials, although they can reach the distal peripheral vascular system and are more flexible and convenient to introduce, if the target location is located in a tortuous blood vessel, there may be problems with catheter insertion and removal after embolization. Although the penetration depth and curing time of embolization can be adjusted by adjusting the proportion of each component, the blood flow impact before curing still requires additional devices (such as solid stents / balloons) to be implanted in the body for auxiliary blockage, which undoubtedly increases the product cost and the difficulty of surgical operation.

[0033] In response to the above problems, this case provides a magnetically controllable liquid embolization robot, which is a pure liquid embolization technology. In vitro, it is a mixed liquid of embolic material and magnetic powder particles. When used, it is injected into the blood environment in the body and fixed at the target site through magnetic control, or it uses magnetic control to flow to the target site and fix in complex and tortuous blood vessels. The ionic cross-linking reaction occurs in the blood environment and it is completely solidified into a gel at the target site to complete the embolization. The entire product has low cost and does not require the implantation of additional auxiliary materials. It has broken through the existing solid embolization and solid-liquid combined embolization technologies, has strong safety and practicality, and is flexible and convenient to implement.

[0034] The following, combined with the accompanying drawings, provides a clear and complete description of how the technical solution of this case is implemented, using the example of abnormal aneurysm hemorrhage and embolism. Obviously, the described embodiments represent only a portion of the embodiments of this case, and not all of them. Based on the embodiments of this case, all other embodiments derived by persons of ordinary skill in the art without inventive effort are within the scope of protection of this application.

[0035] As shown in Figure 1, the liquid embolization robot is a mixed solution before entering the blood vessel. The mixed solution is a mixture of embolic material and magnetic particles, with the magnetic particles accounting for 15% to 65% by weight. During use, the mixed liquid is injected into the blood environment in the body, where it undergoes a phase change and transforms into a solid, filling the bleeding area.

[0036] The magnetic powder particles can be iron nitride magnetic powder, alloy magnetic powder, silicon steel magnetic powder and magnetic nanocrystalline materials.

[0037] In one exemplary composition, the mixed solution primarily consists of EVOH (ethylene vinyl alcohol) copolymer, DMSO (dimethyl sulfoxide), and NdFeB (neodymium iron boron). NdFeB is a magnetic powder particle, accounting for 20% by weight. In some embodiments, the weight percentage may be 15%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, etc., depending on the distance between the in vivo embolization site and the external magnetic control device.

[0038] In one preparation method of this mixed solution, the preparation steps include:

[0039] First, solid EVOH particles are dissolved in DMSO (8% by weight EVOH and 92% by weight DMSO) in a 60°C water bath for 1-2 hours until the EVOH particles are completely dissolved, resulting in a clear, transparent liquid mixture. Then, 20% by weight NdFeB magnetic particles are added to the EVOH / DMSO mixture to create a liquid embolization robot solution.

[0040] If you need to increase the viscosity of the solution, you can increase the EVOH concentration to 16%. The higher the EVOH concentration, the faster the curing and the harder the cured gel.

[0041] If a large amount of magnetic powder settles to the bottom of the solution, an anti-settling agent with a concentration between 0.2% and 0.5% can be added. Depending on the content of magnetic powder, the content of the anti-dust agent may be 0.2%, 0.3%, 0.4%, 0.5%, etc.

[0042] The obtained solution was shaken with a mixer to evenly distribute the magnetic powder in the solution.

[0043] When the mixed solution is shaken and mixed evenly, it is in the form of a liquid with good fluidity and can be injected into the body through a syringe. The mixed solution gradually solidifies to form a colloid due to ionic cross-linking in the blood environment. According to the embolism site and the injection position of the mixed solution, the content / concentration of EVOH is adjusted to control the solidification time of the mixed solution. Generally, when the mixed solution enters the blood environment, an ionic cross-linking reaction will occur in about 2 seconds to form a soft colloid with fluidity (similar to snot). At this time, it can still flow along the blood vessels. When it reaches the embolism site, it will solidify and complete embolism can be achieved. In the embodiment, depending on the possible flow time in the blood vessels, it may be possible to completely solidify it within 5 minutes, 10 minutes or 15 minutes.

[0044] Since there is magnetic powder in the mixed solution, it can be fixed to the bleeding site of the aneurysm through magnetic control, which can resist the impact of blood flow and avoid ectopic placement caused by blood flow scouring. The whole process does not require additional devices to block the neck of the aneurysm. Under continuous injection, the aneurysm can be embolized and cured after the bleeding site of the aneurysm is completely solidified. This method improves the safety and flexibility of the use of liquid embolic materials. If the embolization site is located in a more tortuous vascular structure, the mixed solution injected into the body can be driven by magnetic control to flow to the embolization site before it is completely solidified, and fixed by magnetic control. When it is completely solidified, embolization can be achieved.

[0045] In a magnetically controlled embolization system, the system includes the aforementioned liquid embolization robot and a magnetic control device. The magnetic control device provides a magnetic field that allows the liquid embolization robot to be fixed at the target site or to flow to the target site and then be fixed. The working principle of the magnetically controlled embolization system will be described using the example of embolization of abnormal aneurysm bleeding.

[0046] After the liquid embolization robot's mixed solution is prepared and shaken thoroughly, an appropriate amount is withdrawn using a syringe for later use. Prior to the interventional embolization procedure, under the guidance of a DSA (digital subtraction angiography) imaging device, a catheter is inserted into the abnormal bleeding site of the aneurysm in the patient's body requiring embolization. To prevent the mixed solution from prematurely solidifying and clogging the catheter upon contact with water in the catheter, the catheter is pre-flushed with DMSO solvent, and the solution in the syringe is then pushed through the catheter into the aneurysm. Magnetic control is applied outside the aneurysm. After the solution is drawn out of the syringe, the mixed solution flows to the target site and becomes fixed under the influence of magnetic control. Contact with ionic components in the blood gradually solidifies into a solid colloid. This magnetic fixation prevents high-speed arterial blood flow from causing ectopic placement. Continuous infusion stimulates the formation of a thrombus within the aneurysm, blocking abnormal blood flow within the aneurysm and completing the treatment of the aneurysm in the vascular system. The entire process does not require additional devices to occlude the aneurysm neck, and the procedure is safe and flexible.

[0047] As shown in Figure 2 (A), if the magnetic control device is removed, the liquid embolization robot, which is the existing liquid embolization robot, inside the aneurysm will be unable or difficult to stay inside the aneurysm for embolization due to blood flow rushing away from the aneurysm. Figure 2 (B) shows that under the magnetic control fixation of the rotating magnet, the liquid embolization robot can resist the impact of blood flow, continuously inject, and completely conform to the shape of the aneurysm to solidify and complete embolization without the need for additional equipment. At the same time, as shown in Figure 2 (C), if a tortuous vascular structure is encountered, the liquid embolization robot will spontaneously form into a soft colloid in the blood vessel according to the vascular structure in the body. Under the control of the spherical rotating magnet, it will flow into the target aneurysm, gradually aggregate and solidify to complete safe and effective embolization. This reduces the risk of using liquid embolic agents and the difficulty of embolization surgery, and solves the problem of microcatheters being difficult to reach in complex vascular situations in current traditional embolization procedures.

[0048] In summary, compared with existing liquid embolic materials, the liquid embolic robot in this solution can be fixed at the target position by magnetic control after being injected into the blood environment in the body, or it can flow to the target site and be fixed by magnetic control in complex and tortuous blood vessels. It undergoes ionic cross-linking reaction in the blood environment and completely solidifies into a colloid at the target site to complete the embolization. The system composed of it and the magnetic control device can resist the impact of blood flow without the assistance of additional medical devices. Under the condition of continuous injection, it gradually aggregates and solidifies into a large colloid to complete the embolization. For the complex vascular structures that are difficult to reach with microcatheters in traditional liquid material embolization, the liquid embolic robot in this solution can move autonomously to the target aneurysm under magnetic control drive to complete effective embolization, which is safe and flexible to use.

[0049] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments and application fields. The above-mentioned specific embodiments are merely illustrative and instructive, and are not restrictive. A person skilled in the art, guided by this specification and without departing from the scope of protection of the claims of the present invention, may also devise various forms, all of which fall within the scope of protection of the present invention.

Claims

1. A magnetically controllable liquid embolization robot, characterized in that: The liquid embolization robot is a mixed solution of an embolization material and magnetic powder particles in vitro, and the mass ratio of the magnetic powder particles is 15%-65%; During use, the mixed liquid is injected into the in-vivo blood environment and fixed at the target site by magnetic control, or flows to the target site by magnetic control and is fixed, and ion cross-linking reaction occurs in the blood environment and is completely cured into a jelly at the target site to achieve embolization.

2. The liquid embolization robot according to claim 1, characterized in that, In a preparation method of the liquid embolization robot, the preparation steps include: Using EVOH (ethylene-vinyl alcohol) copolymer and DMSO (dimethyl sulfoxide) as the embolization material, wherein the mass ratio of the EVOH (ethylene-vinyl alcohol) copolymer solid particles in the mixed solution is 8%-16%; Dissolving the EVOH (ethylene-vinyl alcohol) copolymer solid particles in DMSO (dimethyl sulfoxide) to obtain a clear and transparent mixed liquid; Adding magnetic powder particles to the mixed liquid to obtain a liquid embolization robot solution.

3. The liquid embolization robot according to claim 2, characterized in that, Controlling the content / concentration of the EVOH (ethylene-vinyl alcohol) copolymer to control the complete curing time of the ion cross-linking reaction of the liquid embolization robot in the blood environment.

4. The liquid embolization robot according to claim 1, characterized in that: After adding the magnetic powder particles, adding an anti-settling agent with a concentration of 0.2%-0.5%.

5. The liquid embolization robot according to claim 1, characterized in that: The magnetic powder particles are NdFeB (neodymium iron boron).

6. A magnetically controllable embolization system, characterized in that: The system includes a magnetic control device and the liquid embolization robot according to any one of claims 1-5, wherein: the magnetic control device provides a magnetic field for the liquid embolization robot to be fixed at the target site or flow to the target site and be fixed.

7. The system according to claim 6, characterized in that: The magnetic control device is a spherical rotating magnet.

8. The system according to claim 6, characterized in that: The system further includes a catheter, and the catheter is used to push the uniform liquid embolization robot solution into the blood vessel or the target site to be embolized.

9. The system according to claim 8, characterized in that: Before use, the catheter is rinsed with a DMSO (dimethyl sulfoxide) solvent.

10. A method for preparing a magnetically controllable liquid embolization robot, characterized in that, The steps include: Using EVOH (ethylene-vinyl alcohol) copolymer and DMSO (dimethyl sulfoxide) as the embolization material, wherein the mass ratio of the EVOH (ethylene-vinyl alcohol) copolymer solid particles in the mixed solution is 8%-16%; Dissolving the EVOH (ethylene-vinyl alcohol) copolymer solid particles in DMSO (dimethyl sulfoxide) to obtain a clear and transparent mixed liquid; Adding magnetic powder particles with a mass ratio of 15%-25% to the mixed liquid to obtain a liquid embolization robot solution.

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